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gerrit-public.fairphone.software / kernel / msm-4.9 / d6b0c53723753fc0cfda63f56735b225c43e1e9a / . / drivers / usb / serial / io_edgeport.c
blob: b85d2156dfdc49c3fa211b0efd50a61b8ed497fa [file] [log] [blame]
/*
* Edgeport USB Serial Converter driver
*
* Copyright (C) 2000 Inside Out Networks, All rights reserved.
* Copyright (C) 2001-2002 Greg Kroah-Hartman <greg@kroah.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Supports the following devices:
* Edgeport/4
* Edgeport/4t
* Edgeport/2
* Edgeport/4i
* Edgeport/2i
* Edgeport/421
* Edgeport/21
* Rapidport/4
* Edgeport/8
* Edgeport/2D8
* Edgeport/4D8
* Edgeport/8i
*
* For questions or problems with this driver, contact Inside Out
* Networks technical support, or Peter Berger <pberger@brimson.com>,
* or Al Borchers <alborchers@steinerpoint.com>.
*
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/serial.h>
#include <linux/ioctl.h>
#include <linux/wait.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#include "usb-serial.h"
#include "io_edgeport.h"
#include "io_ionsp.h" /* info for the iosp messages */
#include "io_16654.h" /* 16654 UART defines */
/*
* Version Information
*/
#define DRIVER_VERSION "v2.7"
#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com> and David Iacovelli"
#define DRIVER_DESC "Edgeport USB Serial Driver"
/* First, the latest boot code - for first generation edgeports */
#define IMAGE_ARRAY_NAME BootCodeImage_GEN1
#define IMAGE_VERSION_NAME BootCodeImageVersion_GEN1
#include "io_fw_boot.h" /* the bootloader firmware to download to a device, if it needs it */
/* for second generation edgeports */
#define IMAGE_ARRAY_NAME BootCodeImage_GEN2
#define IMAGE_VERSION_NAME BootCodeImageVersion_GEN2
#include "io_fw_boot2.h" /* the bootloader firmware to download to a device, if it needs it */
/* Then finally the main run-time operational code - for first generation edgeports */
#define IMAGE_ARRAY_NAME OperationalCodeImage_GEN1
#define IMAGE_VERSION_NAME OperationalCodeImageVersion_GEN1
#include "io_fw_down.h" /* Define array OperationalCodeImage[] */
/* for second generation edgeports */
#define IMAGE_ARRAY_NAME OperationalCodeImage_GEN2
#define IMAGE_VERSION_NAME OperationalCodeImageVersion_GEN2
#include "io_fw_down2.h" /* Define array OperationalCodeImage[] */
#define MAX_NAME_LEN 64
#define CHASE_TIMEOUT (5*HZ) /* 5 seconds */
#define OPEN_TIMEOUT (5*HZ) /* 5 seconds */
#define COMMAND_TIMEOUT (5*HZ) /* 5 seconds */
/* receive port state */
enum RXSTATE {
EXPECT_HDR1 = 0, /* Expect header byte 1 */
EXPECT_HDR2 = 1, /* Expect header byte 2 */
EXPECT_DATA = 2, /* Expect 'RxBytesRemaining' data */
EXPECT_HDR3 = 3, /* Expect header byte 3 (for status hdrs only) */
};
/* Transmit Fifo
* This Transmit queue is an extension of the edgeport Rx buffer.
* The maximum amount of data buffered in both the edgeport
* Rx buffer (maxTxCredits) and this buffer will never exceed maxTxCredits.
*/
struct TxFifo {
unsigned int head; /* index to head pointer (write) */
unsigned int tail; /* index to tail pointer (read) */
unsigned int count; /* Bytes in queue */
unsigned int size; /* Max size of queue (equal to Max number of TxCredits) */
unsigned char *fifo; /* allocated Buffer */
};
/* This structure holds all of the local port information */
struct edgeport_port {
__u16 txCredits; /* our current credits for this port */
__u16 maxTxCredits; /* the max size of the port */
struct TxFifo txfifo; /* transmit fifo -- size will be maxTxCredits */
struct urb *write_urb; /* write URB for this port */
char write_in_progress; /* TRUE while a write URB is outstanding */
spinlock_t ep_lock;
__u8 shadowLCR; /* last LCR value received */
__u8 shadowMCR; /* last MCR value received */
__u8 shadowMSR; /* last MSR value received */
__u8 shadowLSR; /* last LSR value received */
__u8 shadowXonChar; /* last value set as XON char in Edgeport */
__u8 shadowXoffChar; /* last value set as XOFF char in Edgeport */
__u8 validDataMask;
__u32 baudRate;
char open;
char openPending;
char commandPending;
char closePending;
char chaseResponsePending;
wait_queue_head_t wait_chase; /* for handling sleeping while waiting for chase to finish */
wait_queue_head_t wait_open; /* for handling sleeping while waiting for open to finish */
wait_queue_head_t wait_command; /* for handling sleeping while waiting for command to finish */
wait_queue_head_t delta_msr_wait; /* for handling sleeping while waiting for msr change to happen */
struct async_icount icount;
struct usb_serial_port *port; /* loop back to the owner of this object */
};
/* This structure holds all of the individual device information */
struct edgeport_serial {
char name[MAX_NAME_LEN+2]; /* string name of this device */
struct edge_manuf_descriptor manuf_descriptor; /* the manufacturer descriptor */
struct edge_boot_descriptor boot_descriptor; /* the boot firmware descriptor */
struct edgeport_product_info product_info; /* Product Info */
__u8 interrupt_in_endpoint; /* the interrupt endpoint handle */
unsigned char * interrupt_in_buffer; /* the buffer we use for the interrupt endpoint */
struct urb * interrupt_read_urb; /* our interrupt urb */
__u8 bulk_in_endpoint; /* the bulk in endpoint handle */
unsigned char * bulk_in_buffer; /* the buffer we use for the bulk in endpoint */
struct urb * read_urb; /* our bulk read urb */
int read_in_progress;
spinlock_t es_lock;
__u8 bulk_out_endpoint; /* the bulk out endpoint handle */
__s16 rxBytesAvail; /* the number of bytes that we need to read from this device */
enum RXSTATE rxState; /* the current state of the bulk receive processor */
__u8 rxHeader1; /* receive header byte 1 */
__u8 rxHeader2; /* receive header byte 2 */
__u8 rxHeader3; /* receive header byte 3 */
__u8 rxPort; /* the port that we are currently receiving data for */
__u8 rxStatusCode; /* the receive status code */
__u8 rxStatusParam; /* the receive status paramater */
__s16 rxBytesRemaining; /* the number of port bytes left to read */
struct usb_serial *serial; /* loop back to the owner of this object */
};
/* baud rate information */
struct divisor_table_entry {
__u32 BaudRate;
__u16 Divisor;
};
//
// Define table of divisors for Rev A EdgePort/4 hardware
// These assume a 3.6864MHz crystal, the standard /16, and
// MCR.7 = 0.
//
static const struct divisor_table_entry divisor_table[] = {
{ 50, 4608},
{ 75, 3072},
{ 110, 2095}, /* 2094.545455 => 230450 => .0217 % over */
{ 134, 1713}, /* 1713.011152 => 230398.5 => .00065% under */
{ 150, 1536},
{ 300, 768},
{ 600, 384},
{ 1200, 192},
{ 1800, 128},
{ 2400, 96},
{ 4800, 48},
{ 7200, 32},
{ 9600, 24},
{ 14400, 16},
{ 19200, 12},
{ 38400, 6},
{ 57600, 4},
{ 115200, 2},
{ 230400, 1},
};
/* local variables */
static int debug;
static int low_latency = 1; /* tty low latency flag, on by default */
static int CmdUrbs = 0; /* Number of outstanding Command Write Urbs */
/* local function prototypes */
/* function prototypes for all URB callbacks */
static void edge_interrupt_callback (struct urb *urb, struct pt_regs *regs);
static void edge_bulk_in_callback (struct urb *urb, struct pt_regs *regs);
static void edge_bulk_out_data_callback (struct urb *urb, struct pt_regs *regs);
static void edge_bulk_out_cmd_callback (struct urb *urb, struct pt_regs *regs);
/* function prototypes for the usbserial callbacks */
static int edge_open (struct usb_serial_port *port, struct file *filp);
static void edge_close (struct usb_serial_port *port, struct file *filp);
static int edge_write (struct usb_serial_port *port, const unsigned char *buf, int count);
static int edge_write_room (struct usb_serial_port *port);
static int edge_chars_in_buffer (struct usb_serial_port *port);
static void edge_throttle (struct usb_serial_port *port);
static void edge_unthrottle (struct usb_serial_port *port);
static void edge_set_termios (struct usb_serial_port *port, struct termios *old_termios);
static int edge_ioctl (struct usb_serial_port *port, struct file *file, unsigned int cmd, unsigned long arg);
static void edge_break (struct usb_serial_port *port, int break_state);
static int edge_tiocmget (struct usb_serial_port *port, struct file *file);
static int edge_tiocmset (struct usb_serial_port *port, struct file *file, unsigned int set, unsigned int clear);
static int edge_startup (struct usb_serial *serial);
static void edge_shutdown (struct usb_serial *serial);
#include "io_tables.h" /* all of the devices that this driver supports */
static struct usb_driver io_driver = {
.name = "io_edgeport",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.id_table = id_table_combined,
.no_dynamic_id = 1,
};
/* function prototypes for all of our local functions */
static void process_rcvd_data (struct edgeport_serial *edge_serial, unsigned char *buffer, __u16 bufferLength);
static void process_rcvd_status (struct edgeport_serial *edge_serial, __u8 byte2, __u8 byte3);
static void edge_tty_recv (struct device *dev, struct tty_struct *tty, unsigned char *data, int length);
static void handle_new_msr (struct edgeport_port *edge_port, __u8 newMsr);
static void handle_new_lsr (struct edgeport_port *edge_port, __u8 lsrData, __u8 lsr, __u8 data);
static int send_iosp_ext_cmd (struct edgeport_port *edge_port, __u8 command, __u8 param);
static int calc_baud_rate_divisor (int baud_rate, int *divisor);
static int send_cmd_write_baud_rate (struct edgeport_port *edge_port, int baudRate);
static void change_port_settings (struct edgeport_port *edge_port, struct termios *old_termios);
static int send_cmd_write_uart_register (struct edgeport_port *edge_port, __u8 regNum, __u8 regValue);
static int write_cmd_usb (struct edgeport_port *edge_port, unsigned char *buffer, int writeLength);
static void send_more_port_data (struct edgeport_serial *edge_serial, struct edgeport_port *edge_port);
static int sram_write (struct usb_serial *serial, __u16 extAddr, __u16 addr, __u16 length, __u8 *data);
static int rom_read (struct usb_serial *serial, __u16 extAddr, __u16 addr, __u16 length, __u8 *data);
static int rom_write (struct usb_serial *serial, __u16 extAddr, __u16 addr, __u16 length, __u8 *data);
static void get_manufacturing_desc (struct edgeport_serial *edge_serial);
static void get_boot_desc (struct edgeport_serial *edge_serial);
static void load_application_firmware (struct edgeport_serial *edge_serial);
static void unicode_to_ascii(char *string, int buflen, __le16 *unicode, int unicode_size);
// ************************************************************************
// ************************************************************************
// ************************************************************************
// ************************************************************************
/************************************************************************
* *
* update_edgeport_E2PROM() Compare current versions of *
* Boot ROM and Manufacture *
* Descriptors with versions *
* embedded in this driver *
* *
************************************************************************/
static void update_edgeport_E2PROM (struct edgeport_serial *edge_serial)
{
__u32 BootCurVer;
__u32 BootNewVer;
__u8 BootMajorVersion;
__u8 BootMinorVersion;
__le16 BootBuildNumber;
__u8 *BootImage;
__u32 BootSize;
struct edge_firmware_image_record *record;
unsigned char *firmware;
int response;
switch (edge_serial->product_info.iDownloadFile) {
case EDGE_DOWNLOAD_FILE_I930:
BootMajorVersion = BootCodeImageVersion_GEN1.MajorVersion;
BootMinorVersion = BootCodeImageVersion_GEN1.MinorVersion;
BootBuildNumber = cpu_to_le16(BootCodeImageVersion_GEN1.BuildNumber);
BootImage = &BootCodeImage_GEN1[0];
BootSize = sizeof( BootCodeImage_GEN1 );
break;
case EDGE_DOWNLOAD_FILE_80251:
BootMajorVersion = BootCodeImageVersion_GEN2.MajorVersion;
BootMinorVersion = BootCodeImageVersion_GEN2.MinorVersion;
BootBuildNumber = cpu_to_le16(BootCodeImageVersion_GEN2.BuildNumber);
BootImage = &BootCodeImage_GEN2[0];
BootSize = sizeof( BootCodeImage_GEN2 );
break;
default:
return;
}
// Check Boot Image Version
BootCurVer = (edge_serial->boot_descriptor.MajorVersion << 24) +
(edge_serial->boot_descriptor.MinorVersion << 16) +
le16_to_cpu(edge_serial->boot_descriptor.BuildNumber);
BootNewVer = (BootMajorVersion << 24) +
(BootMinorVersion << 16) +
le16_to_cpu(BootBuildNumber);
dbg("Current Boot Image version %d.%d.%d",
edge_serial->boot_descriptor.MajorVersion,
edge_serial->boot_descriptor.MinorVersion,
le16_to_cpu(edge_serial->boot_descriptor.BuildNumber));
if (BootNewVer > BootCurVer) {
dbg("**Update Boot Image from %d.%d.%d to %d.%d.%d",
edge_serial->boot_descriptor.MajorVersion,
edge_serial->boot_descriptor.MinorVersion,
le16_to_cpu(edge_serial->boot_descriptor.BuildNumber),
BootMajorVersion,
BootMinorVersion,
le16_to_cpu(BootBuildNumber));
dbg("Downloading new Boot Image");
firmware = BootImage;
for (;;) {
record = (struct edge_firmware_image_record *)firmware;
response = rom_write (edge_serial->serial, le16_to_cpu(record->ExtAddr), le16_to_cpu(record->Addr), le16_to_cpu(record->Len), &record->Data[0]);
if (response < 0) {
dev_err(&edge_serial->serial->dev->dev, "rom_write failed (%x, %x, %d)\n", le16_to_cpu(record->ExtAddr), le16_to_cpu(record->Addr), le16_to_cpu(record->Len));
break;
}
firmware += sizeof (struct edge_firmware_image_record) + le16_to_cpu(record->Len);
if (firmware >= &BootImage[BootSize]) {
break;
}
}
} else {
dbg("Boot Image -- already up to date");
}
}
/************************************************************************
* *
* Get string descriptor from device *
* *
************************************************************************/
static int get_string (struct usb_device *dev, int Id, char *string, int buflen)
{
struct usb_string_descriptor StringDesc;
struct usb_string_descriptor *pStringDesc;
dbg("%s - USB String ID = %d", __FUNCTION__, Id );
if (!usb_get_descriptor(dev, USB_DT_STRING, Id, &StringDesc, sizeof(StringDesc))) {
return 0;
}
pStringDesc = kmalloc (StringDesc.bLength, GFP_KERNEL);
if (!pStringDesc) {
return 0;
}
if (!usb_get_descriptor(dev, USB_DT_STRING, Id, pStringDesc, StringDesc.bLength )) {
kfree(pStringDesc);
return 0;
}
unicode_to_ascii(string, buflen, pStringDesc->wData, pStringDesc->bLength/2);
kfree(pStringDesc);
return strlen(string);
}
#if 0
/************************************************************************
*
* Get string descriptor from device
*
************************************************************************/
static int get_string_desc (struct usb_device *dev, int Id, struct usb_string_descriptor **pRetDesc)
{
struct usb_string_descriptor StringDesc;
struct usb_string_descriptor *pStringDesc;
dbg("%s - USB String ID = %d", __FUNCTION__, Id );
if (!usb_get_descriptor(dev, USB_DT_STRING, Id, &StringDesc, sizeof(StringDesc))) {
return 0;
}
pStringDesc = kmalloc (StringDesc.bLength, GFP_KERNEL);
if (!pStringDesc) {
return -1;
}
if (!usb_get_descriptor(dev, USB_DT_STRING, Id, pStringDesc, StringDesc.bLength )) {
kfree(pStringDesc);
return -1;
}
*pRetDesc = pStringDesc;
return 0;
}
#endif
static void get_product_info(struct edgeport_serial *edge_serial)
{
struct edgeport_product_info *product_info = &edge_serial->product_info;
memset (product_info, 0, sizeof(struct edgeport_product_info));
product_info->ProductId = (__u16)(le16_to_cpu(edge_serial->serial->dev->descriptor.idProduct) & ~ION_DEVICE_ID_80251_NETCHIP);
product_info->NumPorts = edge_serial->manuf_descriptor.NumPorts;
product_info->ProdInfoVer = 0;
product_info->RomSize = edge_serial->manuf_descriptor.RomSize;
product_info->RamSize = edge_serial->manuf_descriptor.RamSize;
product_info->CpuRev = edge_serial->manuf_descriptor.CpuRev;
product_info->BoardRev = edge_serial->manuf_descriptor.BoardRev;
product_info->BootMajorVersion = edge_serial->boot_descriptor.MajorVersion;
product_info->BootMinorVersion = edge_serial->boot_descriptor.MinorVersion;
product_info->BootBuildNumber = edge_serial->boot_descriptor.BuildNumber;
memcpy(product_info->ManufactureDescDate, edge_serial->manuf_descriptor.DescDate, sizeof(edge_serial->manuf_descriptor.DescDate));
// check if this is 2nd generation hardware
if (le16_to_cpu(edge_serial->serial->dev->descriptor.idProduct) & ION_DEVICE_ID_80251_NETCHIP) {
product_info->FirmwareMajorVersion = OperationalCodeImageVersion_GEN2.MajorVersion;
product_info->FirmwareMinorVersion = OperationalCodeImageVersion_GEN2.MinorVersion;
product_info->FirmwareBuildNumber = cpu_to_le16(OperationalCodeImageVersion_GEN2.BuildNumber);
product_info->iDownloadFile = EDGE_DOWNLOAD_FILE_80251;
} else {
product_info->FirmwareMajorVersion = OperationalCodeImageVersion_GEN1.MajorVersion;
product_info->FirmwareMinorVersion = OperationalCodeImageVersion_GEN1.MinorVersion;
product_info->FirmwareBuildNumber = cpu_to_le16(OperationalCodeImageVersion_GEN1.BuildNumber);
product_info->iDownloadFile = EDGE_DOWNLOAD_FILE_I930;
}
// Determine Product type and set appropriate flags
switch (DEVICE_ID_FROM_USB_PRODUCT_ID(product_info->ProductId)) {
case ION_DEVICE_ID_EDGEPORT_COMPATIBLE:
case ION_DEVICE_ID_EDGEPORT_4T:
case ION_DEVICE_ID_EDGEPORT_4:
case ION_DEVICE_ID_EDGEPORT_2:
case ION_DEVICE_ID_EDGEPORT_8_DUAL_CPU:
case ION_DEVICE_ID_EDGEPORT_8:
case ION_DEVICE_ID_EDGEPORT_421:
case ION_DEVICE_ID_EDGEPORT_21:
case ION_DEVICE_ID_EDGEPORT_2_DIN:
case ION_DEVICE_ID_EDGEPORT_4_DIN:
case ION_DEVICE_ID_EDGEPORT_16_DUAL_CPU:
product_info->IsRS232 = 1;
break;
case ION_DEVICE_ID_EDGEPORT_2I: // Edgeport/2 RS422/RS485
product_info->IsRS422 = 1;
product_info->IsRS485 = 1;
break;
case ION_DEVICE_ID_EDGEPORT_8I: // Edgeport/4 RS422
case ION_DEVICE_ID_EDGEPORT_4I: // Edgeport/4 RS422
product_info->IsRS422 = 1;
break;
}
// Dump Product Info structure
dbg("**Product Information:");
dbg(" ProductId %x", product_info->ProductId );
dbg(" NumPorts %d", product_info->NumPorts );
dbg(" ProdInfoVer %d", product_info->ProdInfoVer );
dbg(" IsServer %d", product_info->IsServer);
dbg(" IsRS232 %d", product_info->IsRS232 );
dbg(" IsRS422 %d", product_info->IsRS422 );
dbg(" IsRS485 %d", product_info->IsRS485 );
dbg(" RomSize %d", product_info->RomSize );
dbg(" RamSize %d", product_info->RamSize );
dbg(" CpuRev %x", product_info->CpuRev );
dbg(" BoardRev %x", product_info->BoardRev);
dbg(" BootMajorVersion %d.%d.%d", product_info->BootMajorVersion,
product_info->BootMinorVersion,
le16_to_cpu(product_info->BootBuildNumber));
dbg(" FirmwareMajorVersion %d.%d.%d", product_info->FirmwareMajorVersion,
product_info->FirmwareMinorVersion,
le16_to_cpu(product_info->FirmwareBuildNumber));
dbg(" ManufactureDescDate %d/%d/%d", product_info->ManufactureDescDate[0],
product_info->ManufactureDescDate[1],
product_info->ManufactureDescDate[2]+1900);
dbg(" iDownloadFile 0x%x", product_info->iDownloadFile);
}
/************************************************************************/
/************************************************************************/
/* U S B C A L L B A C K F U N C T I O N S */
/* U S B C A L L B A C K F U N C T I O N S */
/************************************************************************/
/************************************************************************/
/*****************************************************************************
* edge_interrupt_callback
* this is the callback function for when we have received data on the
* interrupt endpoint.
*****************************************************************************/
static void edge_interrupt_callback (struct urb *urb, struct pt_regs *regs)
{
struct edgeport_serial *edge_serial = (struct edgeport_serial *)urb->context;
struct edgeport_port *edge_port;
struct usb_serial_port *port;
unsigned char *data = urb->transfer_buffer;
int length = urb->actual_length;
int bytes_avail;
int position;
int txCredits;
int portNumber;
int result;
dbg("%s", __FUNCTION__);
switch (urb->status) {
case 0:
/* success */
break;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
/* this urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
return;
default:
dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
goto exit;
}
// process this interrupt-read even if there are no ports open
if (length) {
usb_serial_debug_data(debug, &edge_serial->serial->dev->dev, __FUNCTION__, length, data);
if (length > 1) {
bytes_avail = data[0] | (data[1] << 8);
if (bytes_avail) {
spin_lock(&edge_serial->es_lock);
edge_serial->rxBytesAvail += bytes_avail;
dbg("%s - bytes_avail=%d, rxBytesAvail=%d, read_in_progress=%d", __FUNCTION__, bytes_avail, edge_serial->rxBytesAvail, edge_serial->read_in_progress);
if (edge_serial->rxBytesAvail > 0 &&
!edge_serial->read_in_progress) {
dbg("%s - posting a read", __FUNCTION__);
edge_serial->read_in_progress = TRUE;
/* we have pending bytes on the bulk in pipe, send a request */
edge_serial->read_urb->dev = edge_serial->serial->dev;
result = usb_submit_urb(edge_serial->read_urb, GFP_ATOMIC);
if (result) {
dev_err(&edge_serial->serial->dev->dev, "%s - usb_submit_urb(read bulk) failed with result = %d\n", __FUNCTION__, result);
edge_serial->read_in_progress = FALSE;
}
}
spin_unlock(&edge_serial->es_lock);
}
}
/* grab the txcredits for the ports if available */
position = 2;
portNumber = 0;
while ((position < length) && (portNumber < edge_serial->serial->num_ports)) {
txCredits = data[position] | (data[position+1] << 8);
if (txCredits) {
port = edge_serial->serial->port[portNumber];
edge_port = usb_get_serial_port_data(port);
if (edge_port->open) {
spin_lock(&edge_port->ep_lock);
edge_port->txCredits += txCredits;
spin_unlock(&edge_port->ep_lock);
dbg("%s - txcredits for port%d = %d", __FUNCTION__, portNumber, edge_port->txCredits);
/* tell the tty driver that something has changed */
if (edge_port->port->tty)
tty_wakeup(edge_port->port->tty);
// Since we have more credit, check if more data can be sent
send_more_port_data(edge_serial, edge_port);
}
}
position += 2;
++portNumber;
}
}
exit:
result = usb_submit_urb (urb, GFP_ATOMIC);
if (result) {
dev_err(&urb->dev->dev, "%s - Error %d submitting control urb\n", __FUNCTION__, result);
}
}
/*****************************************************************************
* edge_bulk_in_callback
* this is the callback function for when we have received data on the
* bulk in endpoint.
*****************************************************************************/
static void edge_bulk_in_callback (struct urb *urb, struct pt_regs *regs)
{
struct edgeport_serial *edge_serial = (struct edgeport_serial *)urb->context;
unsigned char *data = urb->transfer_buffer;
int status;
__u16 raw_data_length;
dbg("%s", __FUNCTION__);
if (urb->status) {
dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
edge_serial->read_in_progress = FALSE;
return;
}
if (urb->actual_length == 0) {
dbg("%s - read bulk callback with no data", __FUNCTION__);
edge_serial->read_in_progress = FALSE;
return;
}
raw_data_length = urb->actual_length;
usb_serial_debug_data(debug, &edge_serial->serial->dev->dev, __FUNCTION__, raw_data_length, data);
spin_lock(&edge_serial->es_lock);
/* decrement our rxBytes available by the number that we just got */
edge_serial->rxBytesAvail -= raw_data_length;
dbg("%s - Received = %d, rxBytesAvail %d", __FUNCTION__, raw_data_length, edge_serial->rxBytesAvail);
process_rcvd_data (edge_serial, data, urb->actual_length);
/* check to see if there's any more data for us to read */
if (edge_serial->rxBytesAvail > 0) {
dbg("%s - posting a read", __FUNCTION__);
edge_serial->read_urb->dev = edge_serial->serial->dev;
status = usb_submit_urb(edge_serial->read_urb, GFP_ATOMIC);
if (status) {
dev_err(&urb->dev->dev, "%s - usb_submit_urb(read bulk) failed, status = %d\n", __FUNCTION__, status);
edge_serial->read_in_progress = FALSE;
}
} else {
edge_serial->read_in_progress = FALSE;
}
spin_unlock(&edge_serial->es_lock);
}
/*****************************************************************************
* edge_bulk_out_data_callback
* this is the callback function for when we have finished sending serial data
* on the bulk out endpoint.
*****************************************************************************/
static void edge_bulk_out_data_callback (struct urb *urb, struct pt_regs *regs)
{
struct edgeport_port *edge_port = (struct edgeport_port *)urb->context;
struct tty_struct *tty;
dbg("%s", __FUNCTION__);
if (urb->status) {
dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
}
tty = edge_port->port->tty;
if (tty && edge_port->open) {
/* let the tty driver wakeup if it has a special write_wakeup function */
tty_wakeup(tty);
}
// Release the Write URB
edge_port->write_in_progress = FALSE;
// Check if more data needs to be sent
send_more_port_data((struct edgeport_serial *)(usb_get_serial_data(edge_port->port->serial)), edge_port);
}
/*****************************************************************************
* BulkOutCmdCallback
* this is the callback function for when we have finished sending a command
* on the bulk out endpoint.
*****************************************************************************/
static void edge_bulk_out_cmd_callback (struct urb *urb, struct pt_regs *regs)
{
struct edgeport_port *edge_port = (struct edgeport_port *)urb->context;
struct tty_struct *tty;
int status = urb->status;
dbg("%s", __FUNCTION__);
CmdUrbs--;
dbg("%s - FREE URB %p (outstanding %d)", __FUNCTION__, urb, CmdUrbs);
/* clean up the transfer buffer */
kfree(urb->transfer_buffer);
/* Free the command urb */
usb_free_urb (urb);
if (status) {
dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, status);
return;
}
/* Get pointer to tty */
tty = edge_port->port->tty;
/* tell the tty driver that something has changed */
if (tty && edge_port->open)
tty_wakeup(tty);
/* we have completed the command */
edge_port->commandPending = FALSE;
wake_up(&edge_port->wait_command);
}
/*****************************************************************************
* Driver tty interface functions
*****************************************************************************/
/*****************************************************************************
* SerialOpen
* this function is called by the tty driver when a port is opened
* If successful, we return 0
* Otherwise we return a negative error number.
*****************************************************************************/
static int edge_open (struct usb_serial_port *port, struct file * filp)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
struct usb_serial *serial;
struct edgeport_serial *edge_serial;
int response;
dbg("%s - port %d", __FUNCTION__, port->number);
if (edge_port == NULL)
return -ENODEV;
if (port->tty)
port->tty->low_latency = low_latency;
/* see if we've set up our endpoint info yet (can't set it up in edge_startup
as the structures were not set up at that time.) */
serial = port->serial;
edge_serial = usb_get_serial_data(serial);
if (edge_serial == NULL) {
return -ENODEV;
}
if (edge_serial->interrupt_in_buffer == NULL) {
struct usb_serial_port *port0 = serial->port[0];
/* not set up yet, so do it now */
edge_serial->interrupt_in_buffer = port0->interrupt_in_buffer;
edge_serial->interrupt_in_endpoint = port0->interrupt_in_endpointAddress;
edge_serial->interrupt_read_urb = port0->interrupt_in_urb;
edge_serial->bulk_in_buffer = port0->bulk_in_buffer;
edge_serial->bulk_in_endpoint = port0->bulk_in_endpointAddress;
edge_serial->read_urb = port0->read_urb;
edge_serial->bulk_out_endpoint = port0->bulk_out_endpointAddress;
/* set up our interrupt urb */
usb_fill_int_urb(edge_serial->interrupt_read_urb,
serial->dev,
usb_rcvintpipe(serial->dev,
port0->interrupt_in_endpointAddress),
port0->interrupt_in_buffer,
edge_serial->interrupt_read_urb->transfer_buffer_length,
edge_interrupt_callback, edge_serial,
edge_serial->interrupt_read_urb->interval);
/* set up our bulk in urb */
usb_fill_bulk_urb(edge_serial->read_urb, serial->dev,
usb_rcvbulkpipe(serial->dev,
port0->bulk_in_endpointAddress),
port0->bulk_in_buffer,
edge_serial->read_urb->transfer_buffer_length,
edge_bulk_in_callback, edge_serial);
edge_serial->read_in_progress = FALSE;
/* start interrupt read for this edgeport
* this interrupt will continue as long as the edgeport is connected */
response = usb_submit_urb (edge_serial->interrupt_read_urb, GFP_KERNEL);
if (response) {
dev_err(&port->dev, "%s - Error %d submitting control urb\n", __FUNCTION__, response);
}
}
/* initialize our wait queues */
init_waitqueue_head(&edge_port->wait_open);
init_waitqueue_head(&edge_port->wait_chase);
init_waitqueue_head(&edge_port->delta_msr_wait);
init_waitqueue_head(&edge_port->wait_command);
/* initialize our icount structure */
memset (&(edge_port->icount), 0x00, sizeof(edge_port->icount));
/* initialize our port settings */
edge_port->txCredits = 0; /* Can't send any data yet */
edge_port->shadowMCR = MCR_MASTER_IE; /* Must always set this bit to enable ints! */
edge_port->chaseResponsePending = FALSE;
/* send a open port command */
edge_port->openPending = TRUE;
edge_port->open = FALSE;
response = send_iosp_ext_cmd (edge_port, IOSP_CMD_OPEN_PORT, 0);
if (response < 0) {
dev_err(&port->dev, "%s - error sending open port command\n", __FUNCTION__);
edge_port->openPending = FALSE;
return -ENODEV;
}
/* now wait for the port to be completely opened */
wait_event_timeout(edge_port->wait_open, (edge_port->openPending != TRUE), OPEN_TIMEOUT);
if (edge_port->open == FALSE) {
/* open timed out */
dbg("%s - open timedout", __FUNCTION__);
edge_port->openPending = FALSE;
return -ENODEV;
}
/* create the txfifo */
edge_port->txfifo.head = 0;
edge_port->txfifo.tail = 0;
edge_port->txfifo.count = 0;
edge_port->txfifo.size = edge_port->maxTxCredits;
edge_port->txfifo.fifo = kmalloc (edge_port->maxTxCredits, GFP_KERNEL);
if (!edge_port->txfifo.fifo) {
dbg("%s - no memory", __FUNCTION__);
edge_close (port, filp);
return -ENOMEM;
}
/* Allocate a URB for the write */
edge_port->write_urb = usb_alloc_urb (0, GFP_KERNEL);
edge_port->write_in_progress = FALSE;
if (!edge_port->write_urb) {
dbg("%s - no memory", __FUNCTION__);
edge_close (port, filp);
return -ENOMEM;
}
dbg("%s(%d) - Initialize TX fifo to %d bytes", __FUNCTION__, port->number, edge_port->maxTxCredits);
dbg("%s exited", __FUNCTION__);
return 0;
}
/************************************************************************
*
* block_until_chase_response
*
* This function will block the close until one of the following:
* 1. Response to our Chase comes from Edgeport
* 2. A timout of 10 seconds without activity has expired
* (1K of Edgeport data @ 2400 baud ==> 4 sec to empty)
*
************************************************************************/
static void block_until_chase_response(struct edgeport_port *edge_port)
{
DEFINE_WAIT(wait);
__u16 lastCredits;
int timeout = 1*HZ;
int loop = 10;
while (1) {
// Save Last credits
lastCredits = edge_port->txCredits;
// Did we get our Chase response
if (edge_port->chaseResponsePending == FALSE) {
dbg("%s - Got Chase Response", __FUNCTION__);
// did we get all of our credit back?
if (edge_port->txCredits == edge_port->maxTxCredits ) {
dbg("%s - Got all credits", __FUNCTION__);
return;
}
}
// Block the thread for a while
prepare_to_wait(&edge_port->wait_chase, &wait, TASK_UNINTERRUPTIBLE);
schedule_timeout(timeout);
finish_wait(&edge_port->wait_chase, &wait);
if (lastCredits == edge_port->txCredits) {
// No activity.. count down.
loop--;
if (loop == 0) {
edge_port->chaseResponsePending = FALSE;
dbg("%s - Chase TIMEOUT", __FUNCTION__);
return;
}
} else {
// Reset timout value back to 10 seconds
dbg("%s - Last %d, Current %d", __FUNCTION__, lastCredits, edge_port->txCredits);
loop = 10;
}
}
}
/************************************************************************
*
* block_until_tx_empty
*
* This function will block the close until one of the following:
* 1. TX count are 0
* 2. The edgeport has stopped
* 3. A timout of 3 seconds without activity has expired
*
************************************************************************/
static void block_until_tx_empty (struct edgeport_port *edge_port)
{
DEFINE_WAIT(wait);
struct TxFifo *fifo = &edge_port->txfifo;
__u32 lastCount;
int timeout = HZ/10;
int loop = 30;
while (1) {
// Save Last count
lastCount = fifo->count;
// Is the Edgeport Buffer empty?
if (lastCount == 0) {
dbg("%s - TX Buffer Empty", __FUNCTION__);
return;
}
// Block the thread for a while
prepare_to_wait (&edge_port->wait_chase, &wait, TASK_UNINTERRUPTIBLE);
schedule_timeout(timeout);
finish_wait(&edge_port->wait_chase, &wait);
dbg("%s wait", __FUNCTION__);
if (lastCount == fifo->count) {
// No activity.. count down.
loop--;
if (loop == 0) {
dbg("%s - TIMEOUT", __FUNCTION__);
return;
}
} else {
// Reset timout value back to seconds
loop = 30;
}
}
}
/*****************************************************************************
* edge_close
* this function is called by the tty driver when a port is closed
*****************************************************************************/
static void edge_close (struct usb_serial_port *port, struct file * filp)
{
struct edgeport_serial *edge_serial;
struct edgeport_port *edge_port;
int status;
dbg("%s - port %d", __FUNCTION__, port->number);
edge_serial = usb_get_serial_data(port->serial);
edge_port = usb_get_serial_port_data(port);
if ((edge_serial == NULL) || (edge_port == NULL))
return;
// block until tx is empty
block_until_tx_empty(edge_port);
edge_port->closePending = TRUE;
/* flush and chase */
edge_port->chaseResponsePending = TRUE;
dbg("%s - Sending IOSP_CMD_CHASE_PORT", __FUNCTION__);
status = send_iosp_ext_cmd (edge_port, IOSP_CMD_CHASE_PORT, 0);
if (status == 0) {
// block until chase finished
block_until_chase_response(edge_port);
} else {
edge_port->chaseResponsePending = FALSE;
}
/* close the port */
dbg("%s - Sending IOSP_CMD_CLOSE_PORT", __FUNCTION__);
send_iosp_ext_cmd (edge_port, IOSP_CMD_CLOSE_PORT, 0);
//port->close = TRUE;
edge_port->closePending = FALSE;
edge_port->open = FALSE;
edge_port->openPending = FALSE;
if (edge_port->write_urb) {
usb_kill_urb(edge_port->write_urb);
}
if (edge_port->write_urb) {
/* if this urb had a transfer buffer already (old transfer) free it */
kfree(edge_port->write_urb->transfer_buffer);
usb_free_urb(edge_port->write_urb);
edge_port->write_urb = NULL;
}
kfree(edge_port->txfifo.fifo);
edge_port->txfifo.fifo = NULL;
dbg("%s exited", __FUNCTION__);
}
/*****************************************************************************
* SerialWrite
* this function is called by the tty driver when data should be written to
* the port.
* If successful, we return the number of bytes written, otherwise we return
* a negative error number.
*****************************************************************************/
static int edge_write (struct usb_serial_port *port, const unsigned char *data, int count)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
struct TxFifo *fifo;
int copySize;
int bytesleft;
int firsthalf;
int secondhalf;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
if (edge_port == NULL)
return -ENODEV;
// get a pointer to the Tx fifo
fifo = &edge_port->txfifo;
spin_lock_irqsave(&edge_port->ep_lock, flags);
// calculate number of bytes to put in fifo
copySize = min ((unsigned int)count, (edge_port->txCredits - fifo->count));
dbg("%s(%d) of %d byte(s) Fifo room %d -- will copy %d bytes", __FUNCTION__,
port->number, count, edge_port->txCredits - fifo->count, copySize);
/* catch writes of 0 bytes which the tty driver likes to give us, and when txCredits is empty */
if (copySize == 0) {
dbg("%s - copySize = Zero", __FUNCTION__);
goto finish_write;
}
// queue the data
// since we can never overflow the buffer we do not have to check for full condition
// the copy is done is two parts -- first fill to the end of the buffer
// then copy the reset from the start of the buffer
bytesleft = fifo->size - fifo->head;
firsthalf = min (bytesleft, copySize);
dbg("%s - copy %d bytes of %d into fifo ", __FUNCTION__, firsthalf, bytesleft);
/* now copy our data */
memcpy(&fifo->fifo[fifo->head], data, firsthalf);
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, firsthalf, &fifo->fifo[fifo->head]);
// update the index and size
fifo->head += firsthalf;
fifo->count += firsthalf;
// wrap the index
if (fifo->head == fifo->size) {
fifo->head = 0;
}
secondhalf = copySize-firsthalf;
if (secondhalf) {
dbg("%s - copy rest of data %d", __FUNCTION__, secondhalf);
memcpy(&fifo->fifo[fifo->head], &data[firsthalf], secondhalf);
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, secondhalf, &fifo->fifo[fifo->head]);
// update the index and size
fifo->count += secondhalf;
fifo->head += secondhalf;
// No need to check for wrap since we can not get to end of fifo in this part
}
finish_write:
spin_unlock_irqrestore(&edge_port->ep_lock, flags);
send_more_port_data((struct edgeport_serial *)usb_get_serial_data(port->serial), edge_port);
dbg("%s wrote %d byte(s) TxCredits %d, Fifo %d", __FUNCTION__, copySize, edge_port->txCredits, fifo->count);
return copySize;
}
/************************************************************************
*
* send_more_port_data()
*
* This routine attempts to write additional UART transmit data
* to a port over the USB bulk pipe. It is called (1) when new
* data has been written to a port's TxBuffer from higher layers
* (2) when the peripheral sends us additional TxCredits indicating
* that it can accept more Tx data for a given port; and (3) when
* a bulk write completes successfully and we want to see if we
* can transmit more.
*
************************************************************************/
static void send_more_port_data(struct edgeport_serial *edge_serial, struct edgeport_port *edge_port)
{
struct TxFifo *fifo = &edge_port->txfifo;
struct urb *urb;
unsigned char *buffer;
int status;
int count;
int bytesleft;
int firsthalf;
int secondhalf;
unsigned long flags;
dbg("%s(%d)", __FUNCTION__, edge_port->port->number);
spin_lock_irqsave(&edge_port->ep_lock, flags);
if (edge_port->write_in_progress ||
!edge_port->open ||
(fifo->count == 0)) {
dbg("%s(%d) EXIT - fifo %d, PendingWrite = %d", __FUNCTION__, edge_port->port->number, fifo->count, edge_port->write_in_progress);
goto exit_send;
}
// since the amount of data in the fifo will always fit into the
// edgeport buffer we do not need to check the write length
// Do we have enough credits for this port to make it worthwhile
// to bother queueing a write. If it's too small, say a few bytes,
// it's better to wait for more credits so we can do a larger
// write.
if (edge_port->txCredits < EDGE_FW_GET_TX_CREDITS_SEND_THRESHOLD(edge_port->maxTxCredits,EDGE_FW_BULK_MAX_PACKET_SIZE)) {
dbg("%s(%d) Not enough credit - fifo %d TxCredit %d", __FUNCTION__, edge_port->port->number, fifo->count, edge_port->txCredits );
goto exit_send;
}
// lock this write
edge_port->write_in_progress = TRUE;
// get a pointer to the write_urb
urb = edge_port->write_urb;
/* make sure transfer buffer is freed */
kfree(urb->transfer_buffer);
urb->transfer_buffer = NULL;
/* build the data header for the buffer and port that we are about to send out */
count = fifo->count;
buffer = kmalloc (count+2, GFP_ATOMIC);
if (buffer == NULL) {
dev_err(&edge_port->port->dev, "%s - no more kernel memory...\n", __FUNCTION__);
edge_port->write_in_progress = FALSE;
goto exit_send;
}
buffer[0] = IOSP_BUILD_DATA_HDR1 (edge_port->port->number - edge_port->port->serial->minor, count);
buffer[1] = IOSP_BUILD_DATA_HDR2 (edge_port->port->number - edge_port->port->serial->minor, count);
/* now copy our data */
bytesleft = fifo->size - fifo->tail;
firsthalf = min (bytesleft, count);
memcpy(&buffer[2], &fifo->fifo[fifo->tail], firsthalf);
fifo->tail += firsthalf;
fifo->count -= firsthalf;
if (fifo->tail == fifo->size) {
fifo->tail = 0;
}
secondhalf = count-firsthalf;
if (secondhalf) {
memcpy(&buffer[2+firsthalf], &fifo->fifo[fifo->tail], secondhalf);
fifo->tail += secondhalf;
fifo->count -= secondhalf;
}
if (count)
usb_serial_debug_data(debug, &edge_port->port->dev, __FUNCTION__, count, &buffer[2]);
/* fill up the urb with all of our data and submit it */
usb_fill_bulk_urb (urb, edge_serial->serial->dev,
usb_sndbulkpipe(edge_serial->serial->dev, edge_serial->bulk_out_endpoint),
buffer, count+2, edge_bulk_out_data_callback, edge_port);
/* decrement the number of credits we have by the number we just sent */
edge_port->txCredits -= count;
edge_port->icount.tx += count;
urb->dev = edge_serial->serial->dev;
status = usb_submit_urb(urb, GFP_ATOMIC);
if (status) {
/* something went wrong */
dev_err(&edge_port->port->dev, "%s - usb_submit_urb(write bulk) failed, status = %d, data lost\n", __FUNCTION__, status);
edge_port->write_in_progress = FALSE;
/* revert the credits as something bad happened. */
edge_port->txCredits += count;
edge_port->icount.tx -= count;
}
dbg("%s wrote %d byte(s) TxCredit %d, Fifo %d", __FUNCTION__, count, edge_port->txCredits, fifo->count);
exit_send:
spin_unlock_irqrestore(&edge_port->ep_lock, flags);
}
/*****************************************************************************
* edge_write_room
* this function is called by the tty driver when it wants to know how many
* bytes of data we can accept for a specific port.
* If successful, we return the amount of room that we have for this port
* (the txCredits),
* Otherwise we return a negative error number.
*****************************************************************************/
static int edge_write_room (struct usb_serial_port *port)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
int room;
unsigned long flags;
dbg("%s", __FUNCTION__);
if (edge_port == NULL)
return -ENODEV;
if (edge_port->closePending == TRUE)
return -ENODEV;
dbg("%s - port %d", __FUNCTION__, port->number);
if (!edge_port->open) {
dbg("%s - port not opened", __FUNCTION__);
return -EINVAL;
}
// total of both buffers is still txCredit
spin_lock_irqsave(&edge_port->ep_lock, flags);
room = edge_port->txCredits - edge_port->txfifo.count;
spin_unlock_irqrestore(&edge_port->ep_lock, flags);
dbg("%s - returns %d", __FUNCTION__, room);
return room;
}
/*****************************************************************************
* edge_chars_in_buffer
* this function is called by the tty driver when it wants to know how many
* bytes of data we currently have outstanding in the port (data that has
* been written, but hasn't made it out the port yet)
* If successful, we return the number of bytes left to be written in the
* system,
* Otherwise we return a negative error number.
*****************************************************************************/
static int edge_chars_in_buffer (struct usb_serial_port *port)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
int num_chars;
unsigned long flags;
dbg("%s", __FUNCTION__);
if (edge_port == NULL)
return -ENODEV;
if (edge_port->closePending == TRUE)
return -ENODEV;
if (!edge_port->open) {
dbg("%s - port not opened", __FUNCTION__);
return -EINVAL;
}
spin_lock_irqsave(&edge_port->ep_lock, flags);
num_chars = edge_port->maxTxCredits - edge_port->txCredits + edge_port->txfifo.count;
spin_unlock_irqrestore(&edge_port->ep_lock, flags);
if (num_chars) {
dbg("%s(port %d) - returns %d", __FUNCTION__, port->number, num_chars);
}
return num_chars;
}
/*****************************************************************************
* SerialThrottle
* this function is called by the tty driver when it wants to stop the data
* being read from the port.
*****************************************************************************/
static void edge_throttle (struct usb_serial_port *port)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
struct tty_struct *tty;
int status;
dbg("%s - port %d", __FUNCTION__, port->number);
if (edge_port == NULL)
return;
if (!edge_port->open) {
dbg("%s - port not opened", __FUNCTION__);
return;
}
tty = port->tty;
if (!tty) {
dbg ("%s - no tty available", __FUNCTION__);
return;
}
/* if we are implementing XON/XOFF, send the stop character */
if (I_IXOFF(tty)) {
unsigned char stop_char = STOP_CHAR(tty);
status = edge_write (port, &stop_char, 1);
if (status <= 0) {
return;
}
}
/* if we are implementing RTS/CTS, toggle that line */
if (tty->termios->c_cflag & CRTSCTS) {
edge_port->shadowMCR &= ~MCR_RTS;
status = send_cmd_write_uart_register(edge_port, MCR, edge_port->shadowMCR);
if (status != 0) {
return;
}
}
return;
}
/*****************************************************************************
* edge_unthrottle
* this function is called by the tty driver when it wants to resume the data
* being read from the port (called after SerialThrottle is called)
*****************************************************************************/
static void edge_unthrottle (struct usb_serial_port *port)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
struct tty_struct *tty;
int status;
dbg("%s - port %d", __FUNCTION__, port->number);
if (edge_port == NULL)
return;
if (!edge_port->open) {
dbg("%s - port not opened", __FUNCTION__);
return;
}
tty = port->tty;
if (!tty) {
dbg ("%s - no tty available", __FUNCTION__);
return;
}
/* if we are implementing XON/XOFF, send the start character */
if (I_IXOFF(tty)) {
unsigned char start_char = START_CHAR(tty);
status = edge_write (port, &start_char, 1);
if (status <= 0) {
return;
}
}
/* if we are implementing RTS/CTS, toggle that line */
if (tty->termios->c_cflag & CRTSCTS) {
edge_port->shadowMCR |= MCR_RTS;
status = send_cmd_write_uart_register(edge_port, MCR, edge_port->shadowMCR);
if (status != 0) {
return;
}
}
return;
}
/*****************************************************************************
* SerialSetTermios
* this function is called by the tty driver when it wants to change the termios structure
*****************************************************************************/
static void edge_set_termios (struct usb_serial_port *port, struct termios *old_termios)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
struct tty_struct *tty = port->tty;
unsigned int cflag;
if (!port->tty || !port->tty->termios) {
dbg ("%s - no tty or termios", __FUNCTION__);
return;
}
cflag = tty->termios->c_cflag;
/* check that they really want us to change something */
if (old_termios) {
if (cflag == old_termios->c_cflag &&
tty->termios->c_iflag == old_termios->c_iflag) {
dbg("%s - nothing to change", __FUNCTION__);
return;
}
}
dbg("%s - clfag %08x iflag %08x", __FUNCTION__,
tty->termios->c_cflag, tty->termios->c_iflag);
if (old_termios) {
dbg("%s - old clfag %08x old iflag %08x", __FUNCTION__,
old_termios->c_cflag, old_termios->c_iflag);
}
dbg("%s - port %d", __FUNCTION__, port->number);
if (edge_port == NULL)
return;
if (!edge_port->open) {
dbg("%s - port not opened", __FUNCTION__);
return;
}
/* change the port settings to the new ones specified */
change_port_settings (edge_port, old_termios);
return;
}
/*****************************************************************************
* get_lsr_info - get line status register info
*
* Purpose: Let user call ioctl() to get info when the UART physically
* is emptied. On bus types like RS485, the transmitter must
* release the bus after transmitting. This must be done when
* the transmit shift register is empty, not be done when the
* transmit holding register is empty. This functionality
* allows an RS485 driver to be written in user space.
*****************************************************************************/
static int get_lsr_info(struct edgeport_port *edge_port, unsigned int __user *value)
{
unsigned int result = 0;
unsigned long flags;
spin_lock_irqsave(&edge_port->ep_lock, flags);
if (edge_port->maxTxCredits == edge_port->txCredits &&
edge_port->txfifo.count == 0) {
dbg("%s -- Empty", __FUNCTION__);
result = TIOCSER_TEMT;
}
spin_unlock_irqrestore(&edge_port->ep_lock, flags);
if (copy_to_user(value, &result, sizeof(int)))
return -EFAULT;
return 0;
}
static int get_number_bytes_avail(struct edgeport_port *edge_port, unsigned int __user *value)
{
unsigned int result = 0;
struct tty_struct *tty = edge_port->port->tty;
if (!tty)
return -ENOIOCTLCMD;
result = tty->read_cnt;
dbg("%s(%d) = %d", __FUNCTION__, edge_port->port->number, result);
if (copy_to_user(value, &result, sizeof(int)))
return -EFAULT;
//return 0;
return -ENOIOCTLCMD;
}
static int edge_tiocmset (struct usb_serial_port *port, struct file *file, unsigned int set, unsigned int clear)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
unsigned int mcr;
dbg("%s - port %d", __FUNCTION__, port->number);
mcr = edge_port->shadowMCR;
if (set & TIOCM_RTS)
mcr |= MCR_RTS;
if (set & TIOCM_DTR)
mcr |= MCR_DTR;
if (set & TIOCM_LOOP)
mcr |= MCR_LOOPBACK;
if (clear & TIOCM_RTS)
mcr &= ~MCR_RTS;
if (clear & TIOCM_DTR)
mcr &= ~MCR_DTR;
if (clear & TIOCM_LOOP)
mcr &= ~MCR_LOOPBACK;
edge_port->shadowMCR = mcr;
send_cmd_write_uart_register(edge_port, MCR, edge_port->shadowMCR);
return 0;
}
static int edge_tiocmget(struct usb_serial_port *port, struct file *file)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
unsigned int result = 0;
unsigned int msr;
unsigned int mcr;
dbg("%s - port %d", __FUNCTION__, port->number);
msr = edge_port->shadowMSR;
mcr = edge_port->shadowMCR;
result = ((mcr & MCR_DTR) ? TIOCM_DTR: 0) /* 0x002 */
| ((mcr & MCR_RTS) ? TIOCM_RTS: 0) /* 0x004 */
| ((msr & EDGEPORT_MSR_CTS) ? TIOCM_CTS: 0) /* 0x020 */
| ((msr & EDGEPORT_MSR_CD) ? TIOCM_CAR: 0) /* 0x040 */
| ((msr & EDGEPORT_MSR_RI) ? TIOCM_RI: 0) /* 0x080 */
| ((msr & EDGEPORT_MSR_DSR) ? TIOCM_DSR: 0); /* 0x100 */
dbg("%s -- %x", __FUNCTION__, result);
return result;
}
static int get_serial_info(struct edgeport_port *edge_port, struct serial_struct __user *retinfo)
{
struct serial_struct tmp;
if (!retinfo)
return -EFAULT;
memset(&tmp, 0, sizeof(tmp));
tmp.type = PORT_16550A;
tmp.line = edge_port->port->serial->minor;
tmp.port = edge_port->port->number;
tmp.irq = 0;
tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
tmp.xmit_fifo_size = edge_port->maxTxCredits;
tmp.baud_base = 9600;
tmp.close_delay = 5*HZ;
tmp.closing_wait = 30*HZ;
// tmp.custom_divisor = state->custom_divisor;
// tmp.hub6 = state->hub6;
// tmp.io_type = state->io_type;
if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
return -EFAULT;
return 0;
}
/*****************************************************************************
* SerialIoctl
* this function handles any ioctl calls to the driver
*****************************************************************************/
static int edge_ioctl (struct usb_serial_port *port, struct file *file, unsigned int cmd, unsigned long arg)
{
DEFINE_WAIT(wait);
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
struct async_icount cnow;
struct async_icount cprev;
struct serial_icounter_struct icount;
dbg("%s - port %d, cmd = 0x%x", __FUNCTION__, port->number, cmd);
switch (cmd) {
// return number of bytes available
case TIOCINQ:
dbg("%s (%d) TIOCINQ", __FUNCTION__, port->number);
return get_number_bytes_avail(edge_port, (unsigned int __user *) arg);
break;
case TIOCSERGETLSR:
dbg("%s (%d) TIOCSERGETLSR", __FUNCTION__, port->number);
return get_lsr_info(edge_port, (unsigned int __user *) arg);
return 0;
case TIOCGSERIAL:
dbg("%s (%d) TIOCGSERIAL", __FUNCTION__, port->number);
return get_serial_info(edge_port, (struct serial_struct __user *) arg);
case TIOCSSERIAL:
dbg("%s (%d) TIOCSSERIAL", __FUNCTION__, port->number);
break;
case TIOCMIWAIT:
dbg("%s (%d) TIOCMIWAIT", __FUNCTION__, port->number);
cprev = edge_port->icount;
while (1) {
prepare_to_wait(&edge_port->delta_msr_wait, &wait, TASK_INTERRUPTIBLE);
schedule();
finish_wait(&edge_port->delta_msr_wait, &wait);
/* see if a signal did it */
if (signal_pending(current))
return -ERESTARTSYS;
cnow = edge_port->icount;
if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
return -EIO; /* no change => error */
if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
return 0;
}
cprev = cnow;
}
/* NOTREACHED */
break;
case TIOCGICOUNT:
cnow = edge_port->icount;
memset(&icount, 0, sizeof(icount));
icount.cts = cnow.cts;
icount.dsr = cnow.dsr;
icount.rng = cnow.rng;
icount.dcd = cnow.dcd;
icount.rx = cnow.rx;
icount.tx = cnow.tx;
icount.frame = cnow.frame;
icount.overrun = cnow.overrun;
icount.parity = cnow.parity;
icount.brk = cnow.brk;
icount.buf_overrun = cnow.buf_overrun;
dbg("%s (%d) TIOCGICOUNT RX=%d, TX=%d", __FUNCTION__, port->number, icount.rx, icount.tx );
if (copy_to_user((void __user *)arg, &icount, sizeof(icount)))
return -EFAULT;
return 0;
}
return -ENOIOCTLCMD;
}
/*****************************************************************************
* SerialBreak
* this function sends a break to the port
*****************************************************************************/
static void edge_break (struct usb_serial_port *port, int break_state)
{
struct edgeport_port *edge_port = usb_get_serial_port_data(port);
int status;
/* flush and chase */
edge_port->chaseResponsePending = TRUE;
dbg("%s - Sending IOSP_CMD_CHASE_PORT", __FUNCTION__);
status = send_iosp_ext_cmd (edge_port, IOSP_CMD_CHASE_PORT, 0);
if (status == 0) {
// block until chase finished
block_until_chase_response(edge_port);
} else {
edge_port->chaseResponsePending = FALSE;
}
if (break_state == -1) {
dbg("%s - Sending IOSP_CMD_SET_BREAK", __FUNCTION__);
status = send_iosp_ext_cmd (edge_port, IOSP_CMD_SET_BREAK, 0);
} else {
dbg("%s - Sending IOSP_CMD_CLEAR_BREAK", __FUNCTION__);
status = send_iosp_ext_cmd (edge_port, IOSP_CMD_CLEAR_BREAK, 0);
}
if (status) {
dbg("%s - error sending break set/clear command.", __FUNCTION__);
}
return;
}
/*****************************************************************************
* process_rcvd_data
* this function handles the data received on the bulk in pipe.
*****************************************************************************/
static void process_rcvd_data (struct edgeport_serial *edge_serial, unsigned char * buffer, __u16 bufferLength)
{
struct usb_serial_port *port;
struct edgeport_port *edge_port;
struct tty_struct *tty;
__u16 lastBufferLength;
__u16 rxLen;
dbg("%s", __FUNCTION__);
lastBufferLength = bufferLength + 1;
while (bufferLength > 0) {
/* failsafe incase we get a message that we don't understand */
if (lastBufferLength == bufferLength) {
dbg("%s - stuck in loop, exiting it.", __FUNCTION__);
break;
}
lastBufferLength = bufferLength;
switch (edge_serial->rxState) {
case EXPECT_HDR1:
edge_serial->rxHeader1 = *buffer;
++buffer;
--bufferLength;
if (bufferLength == 0) {
edge_serial->rxState = EXPECT_HDR2;
break;
}
/* otherwise, drop on through */
case EXPECT_HDR2:
edge_serial->rxHeader2 = *buffer;
++buffer;
--bufferLength;
dbg("%s - Hdr1=%02X Hdr2=%02X", __FUNCTION__, edge_serial->rxHeader1, edge_serial->rxHeader2);
// Process depending on whether this header is
// data or status
if (IS_CMD_STAT_HDR(edge_serial->rxHeader1)) {
// Decode this status header and goto EXPECT_HDR1 (if we
// can process the status with only 2 bytes), or goto
// EXPECT_HDR3 to get the third byte.
edge_serial->rxPort = IOSP_GET_HDR_PORT(edge_serial->rxHeader1);
edge_serial->rxStatusCode = IOSP_GET_STATUS_CODE(edge_serial->rxHeader1);
if (!IOSP_STATUS_IS_2BYTE(edge_serial->rxStatusCode)) {
// This status needs additional bytes. Save what we have
// and then wait for more data.
edge_serial->rxStatusParam = edge_serial->rxHeader2;
edge_serial->rxState = EXPECT_HDR3;
break;
}
// We have all the header bytes, process the status now
process_rcvd_status (edge_serial, edge_serial->rxHeader2, 0);
edge_serial->rxState = EXPECT_HDR1;
break;
} else {
edge_serial->rxPort = IOSP_GET_HDR_PORT(edge_serial->rxHeader1);
edge_serial->rxBytesRemaining = IOSP_GET_HDR_DATA_LEN(edge_serial->rxHeader1, edge_serial->rxHeader2);
dbg("%s - Data for Port %u Len %u", __FUNCTION__, edge_serial->rxPort, edge_serial->rxBytesRemaining);
//ASSERT( DevExt->RxPort < DevExt->NumPorts );
//ASSERT( DevExt->RxBytesRemaining < IOSP_MAX_DATA_LENGTH );
if (bufferLength == 0 ) {
edge_serial->rxState = EXPECT_DATA;
break;
}
// Else, drop through
}
case EXPECT_DATA: // Expect data
if (bufferLength < edge_serial->rxBytesRemaining) {
rxLen = bufferLength;
edge_serial->rxState = EXPECT_DATA; // Expect data to start next buffer
} else {
// BufLen >= RxBytesRemaining
rxLen = edge_serial->rxBytesRemaining;
edge_serial->rxState = EXPECT_HDR1; // Start another header next time
}
bufferLength -= rxLen;
edge_serial->rxBytesRemaining -= rxLen;
/* spit this data back into the tty driver if this port is open */
if (rxLen) {
port = edge_serial->serial->port[edge_serial->rxPort];
edge_port = usb_get_serial_port_data(port);
if (edge_port->open) {
tty = edge_port->port->tty;
if (tty) {
dbg("%s - Sending %d bytes to TTY for port %d", __FUNCTION__, rxLen, edge_serial->rxPort);
edge_tty_recv(&edge_serial->serial->dev->dev, tty, buffer, rxLen);
}
edge_port->icount.rx += rxLen;
}
buffer += rxLen;
}
break;
case EXPECT_HDR3: // Expect 3rd byte of status header
edge_serial->rxHeader3 = *buffer;
++buffer;
--bufferLength;
// We have all the header bytes, process the status now
process_rcvd_status (edge_serial, edge_serial->rxStatusParam, edge_serial->rxHeader3);
edge_serial->rxState = EXPECT_HDR1;
break;
}
}
}
/*****************************************************************************
* process_rcvd_status
* this function handles the any status messages received on the bulk in pipe.
*****************************************************************************/
static void process_rcvd_status (struct edgeport_serial *edge_serial, __u8 byte2, __u8 byte3)
{
struct usb_serial_port *port;
struct edgeport_port *edge_port;
__u8 code = edge_serial->rxStatusCode;
/* switch the port pointer to the one being currently talked about */
port = edge_serial->serial->port[edge_serial->rxPort];
edge_port = usb_get_serial_port_data(port);
if (edge_port == NULL) {
dev_err(&edge_serial->serial->dev->dev, "%s - edge_port == NULL for port %d\n", __FUNCTION__, edge_serial->rxPort);
return;
}
dbg("%s - port %d", __FUNCTION__, edge_serial->rxPort);
if (code == IOSP_EXT_STATUS) {
switch (byte2) {
case IOSP_EXT_STATUS_CHASE_RSP:
// we want to do EXT status regardless of port open/closed
dbg("%s - Port %u EXT CHASE_RSP Data = %02x", __FUNCTION__, edge_serial->rxPort, byte3 );
// Currently, the only EXT_STATUS is Chase, so process here instead of one more call
// to one more subroutine. If/when more EXT_STATUS, there'll be more work to do.
// Also, we currently clear flag and close the port regardless of content of above's Byte3.
// We could choose to do something else when Byte3 says Timeout on Chase from Edgeport,
// like wait longer in block_until_chase_response, but for now we don't.
edge_port->chaseResponsePending = FALSE;
wake_up (&edge_port->wait_chase);
return;
case IOSP_EXT_STATUS_RX_CHECK_RSP:
dbg("%s ========== Port %u CHECK_RSP Sequence = %02x =============\n", __FUNCTION__, edge_serial->rxPort, byte3 );
//Port->RxCheckRsp = TRUE;
return;
}
}
if (code == IOSP_STATUS_OPEN_RSP) {
edge_port->txCredits = GET_TX_BUFFER_SIZE(byte3);
edge_port->maxTxCredits = edge_port->txCredits;
dbg("%s - Port %u Open Response Inital MSR = %02x TxBufferSize = %d", __FUNCTION__, edge_serial->rxPort, byte2, edge_port->txCredits);
handle_new_msr (edge_port, byte2);
/* send the current line settings to the port so we are in sync with any further termios calls */
if (edge_port->port->tty)
change_port_settings (edge_port, edge_port->port->tty->termios);
/* we have completed the open */
edge_port->openPending = FALSE;
edge_port->open = TRUE;
wake_up(&edge_port->wait_open);
return;
}
// If port is closed, silently discard all rcvd status. We can
// have cases where buffered status is received AFTER the close
// port command is sent to the Edgeport.
if ((!edge_port->open ) || (edge_port->closePending)) {
return;
}
switch (code) {
// Not currently sent by Edgeport
case IOSP_STATUS_LSR:
dbg("%s - Port %u LSR Status = %02x", __FUNCTION__, edge_serial->rxPort, byte2);
handle_new_lsr (edge_port, FALSE, byte2, 0);
break;
case IOSP_STATUS_LSR_DATA:
dbg("%s - Port %u LSR Status = %02x, Data = %02x", __FUNCTION__, edge_serial->rxPort, byte2, byte3);
// byte2 is LSR Register
// byte3 is broken data byte
handle_new_lsr (edge_port, TRUE, byte2, byte3);
break;
//
// case IOSP_EXT_4_STATUS:
// dbg("%s - Port %u LSR Status = %02x Data = %02x", __FUNCTION__, edge_serial->rxPort, byte2, byte3);
// break;
//
case IOSP_STATUS_MSR:
dbg("%s - Port %u MSR Status = %02x", __FUNCTION__, edge_serial->rxPort, byte2);
// Process this new modem status and generate appropriate
// events, etc, based on the new status. This routine
// also saves the MSR in Port->ShadowMsr.
handle_new_msr(edge_port, byte2);
break;
default:
dbg("%s - Unrecognized IOSP status code %u\n", __FUNCTION__, code);
break;
}
return;
}
/*****************************************************************************
* edge_tty_recv
* this function passes data on to the tty flip buffer
*****************************************************************************/
static void edge_tty_recv(struct device *dev, struct tty_struct *tty, unsigned char *data, int length)
{
int cnt;
do {
cnt = tty_buffer_request_room(tty, length);
if (cnt < length) {
dev_err(dev, "%s - dropping data, %d bytes lost\n",
__FUNCTION__, length - cnt);
if(cnt == 0)
break;
}
tty_insert_flip_string(tty, data, cnt);
data += cnt;
length -= cnt;
} while (length > 0);
tty_flip_buffer_push(tty);
}
/*****************************************************************************
* handle_new_msr
* this function handles any change to the msr register for a port.
*****************************************************************************/
static void handle_new_msr(struct edgeport_port *edge_port, __u8 newMsr)
{
struct async_icount *icount;
dbg("%s %02x", __FUNCTION__, newMsr);
if (newMsr & (EDGEPORT_MSR_DELTA_CTS | EDGEPORT_MSR_DELTA_DSR | EDGEPORT_MSR_DELTA_RI | EDGEPORT_MSR_DELTA_CD)) {
icount = &edge_port->icount;
/* update input line counters */
if (newMsr & EDGEPORT_MSR_DELTA_CTS) {
icount->cts++;
}
if (newMsr & EDGEPORT_MSR_DELTA_DSR) {
icount->dsr++;
}
if (newMsr & EDGEPORT_MSR_DELTA_CD) {
icount->dcd++;
}
if (newMsr & EDGEPORT_MSR_DELTA_RI) {
icount->rng++;
}
wake_up_interruptible(&edge_port->delta_msr_wait);
}
/* Save the new modem status */
edge_port->shadowMSR = newMsr & 0xf0;
return;
}
/*****************************************************************************
* handle_new_lsr
* this function handles any change to the lsr register for a port.
*****************************************************************************/
static void handle_new_lsr(struct edgeport_port *edge_port, __u8 lsrData, __u8 lsr, __u8 data)
{
__u8 newLsr = (__u8)(lsr & (__u8)(LSR_OVER_ERR | LSR_PAR_ERR | LSR_FRM_ERR | LSR_BREAK));
struct async_icount *icount;
dbg("%s - %02x", __FUNCTION__, newLsr);
edge_port->shadowLSR = lsr;
if (newLsr & LSR_BREAK) {
//
// Parity and Framing errors only count if they
// occur exclusive of a break being
// received.
//
newLsr &= (__u8)(LSR_OVER_ERR | LSR_BREAK);
}
/* Place LSR data byte into Rx buffer */
if (lsrData && edge_port->port->tty)
edge_tty_recv(&edge_port->port->dev, edge_port->port->tty, &data, 1);
/* update input line counters */
icount = &edge_port->icount;
if (newLsr & LSR_BREAK) {
icount->brk++;
}
if (newLsr & LSR_OVER_ERR) {
icount->overrun++;
}
if (newLsr & LSR_PAR_ERR) {
icount->parity++;
}
if (newLsr & LSR_FRM_ERR) {
icount->frame++;
}
return;
}
/****************************************************************************
* sram_write
* writes a number of bytes to the Edgeport device's sram starting at the
* given address.
* If successful returns the number of bytes written, otherwise it returns
* a negative error number of the problem.
****************************************************************************/
static int sram_write (struct usb_serial *serial, __u16 extAddr, __u16 addr, __u16 length, __u8 *data)
{
int result;
__u16 current_length;
unsigned char *transfer_buffer;
dbg("%s - %x, %x, %d", __FUNCTION__, extAddr, addr, length);
transfer_buffer = kmalloc (64, GFP_KERNEL);
if (!transfer_buffer) {
dev_err(&serial->dev->dev, "%s - kmalloc(%d) failed.\n", __FUNCTION__, 64);
return -ENOMEM;
}
/* need to split these writes up into 64 byte chunks */
result = 0;
while (length > 0) {
if (length > 64) {
current_length = 64;
} else {
current_length = length;
}
// dbg("%s - writing %x, %x, %d", __FUNCTION__, extAddr, addr, current_length);
memcpy (transfer_buffer, data, current_length);
result = usb_control_msg (serial->dev, usb_sndctrlpipe(serial->dev, 0), USB_REQUEST_ION_WRITE_RAM,
0x40, addr, extAddr, transfer_buffer, current_length, 300);
if (result < 0)
break;
length -= current_length;
addr += current_length;
data += current_length;
}
kfree (transfer_buffer);
return result;
}
/****************************************************************************
* rom_write
* writes a number of bytes to the Edgeport device's ROM starting at the
* given address.
* If successful returns the number of bytes written, otherwise it returns
* a negative error number of the problem.
****************************************************************************/
static int rom_write (struct usb_serial *serial, __u16 extAddr, __u16 addr, __u16 length, __u8 *data)
{
int result;
__u16 current_length;
unsigned char *transfer_buffer;
// dbg("%s - %x, %x, %d", __FUNCTION__, extAddr, addr, length);
transfer_buffer = kmalloc (64, GFP_KERNEL);
if (!transfer_buffer) {
dev_err(&serial->dev->dev, "%s - kmalloc(%d) failed.\n", __FUNCTION__, 64);
return -ENOMEM;
}
/* need to split these writes up into 64 byte chunks */
result = 0;
while (length > 0) {
if (length > 64) {
current_length = 64;
} else {
current_length = length;
}
// dbg("%s - writing %x, %x, %d", __FUNCTION__, extAddr, addr, current_length);
memcpy (transfer_buffer, data, current_length);
result = usb_control_msg (serial->dev, usb_sndctrlpipe(serial->dev, 0), USB_REQUEST_ION_WRITE_ROM,
0x40, addr, extAddr, transfer_buffer, current_length, 300);
if (result < 0)
break;
length -= current_length;
addr += current_length;
data += current_length;
}
kfree (transfer_buffer);
return result;
}
/****************************************************************************
* rom_read
* reads a number of bytes from the Edgeport device starting at the given
* address.
* If successful returns the number of bytes read, otherwise it returns
* a negative error number of the problem.
****************************************************************************/
static int rom_read (struct usb_serial *serial, __u16 extAddr, __u16 addr, __u16 length, __u8 *data)
{
int result;
__u16 current_length;
unsigned char *transfer_buffer;
dbg("%s - %x, %x, %d", __FUNCTION__, extAddr, addr, length);
transfer_buffer = kmalloc (64, GFP_KERNEL);
if (!transfer_buffer) {
dev_err(&serial->dev->dev, "%s - kmalloc(%d) failed.\n", __FUNCTION__, 64);
return -ENOMEM;
}
/* need to split these reads up into 64 byte chunks */
result = 0;
while (length > 0) {
if (length > 64) {
current_length = 64;
} else {
current_length = length;
}
// dbg("%s - %x, %x, %d", __FUNCTION__, extAddr, addr, current_length);
result = usb_control_msg (serial->dev, usb_rcvctrlpipe(serial->dev, 0), USB_REQUEST_ION_READ_ROM,
0xC0, addr, extAddr, transfer_buffer, current_length, 300);
if (result < 0)
break;
memcpy (data, transfer_buffer, current_length);
length -= current_length;
addr += current_length;
data += current_length;
}
kfree (transfer_buffer);
return result;
}
/****************************************************************************
* send_iosp_ext_cmd
* Is used to send a IOSP message to the Edgeport device
****************************************************************************/
static int send_iosp_ext_cmd (struct edgeport_port *edge_port, __u8 command, __u8 param)
{
unsigned char *buffer;
unsigned char *currentCommand;
int length = 0;
int status = 0;
dbg("%s - %d, %d", __FUNCTION__, command, param);
buffer = kmalloc (10, GFP_ATOMIC);
if (!buffer) {
dev_err(&edge_port->port->dev, "%s - kmalloc(%d) failed.\n", __FUNCTION__, 10);
return -ENOMEM;
}
currentCommand = buffer;
MAKE_CMD_EXT_CMD (&currentCommand, &length,
edge_port->port->number - edge_port->port->serial->minor,
command, param);
status = write_cmd_usb (edge_port, buffer, length);
if (status) {
/* something bad happened, let's free up the memory */
kfree(buffer);
}
return status;
}
/*****************************************************************************
* write_cmd_usb
* this function writes the given buffer out to the bulk write endpoint.
*****************************************************************************/
static int write_cmd_usb (struct edgeport_port *edge_port, unsigned char *buffer, int length)
{
struct edgeport_serial *edge_serial = usb_get_serial_data(edge_port->port->serial);
int status = 0;
struct urb *urb;
int timeout;
usb_serial_debug_data(debug, &edge_port->port->dev, __FUNCTION__, length, buffer);
/* Allocate our next urb */
urb = usb_alloc_urb (0, GFP_ATOMIC);
if (!urb)
return -ENOMEM;
CmdUrbs++;
dbg("%s - ALLOCATE URB %p (outstanding %d)", __FUNCTION__, urb, CmdUrbs);
usb_fill_bulk_urb (urb, edge_serial->serial->dev,
usb_sndbulkpipe(edge_serial->serial->dev, edge_serial->bulk_out_endpoint),
buffer, length, edge_bulk_out_cmd_callback, edge_port);
edge_port->commandPending = TRUE;
status = usb_submit_urb(urb, GFP_ATOMIC);
if (status) {
/* something went wrong */
dev_err(&edge_port->port->dev, "%s - usb_submit_urb(write command) failed, status = %d\n", __FUNCTION__, status);
usb_kill_urb(urb);
usb_free_urb(urb);
CmdUrbs--;
return status;
}
// wait for command to finish
timeout = COMMAND_TIMEOUT;
#if 0
wait_event (&edge_port->wait_command, (edge_port->commandPending == FALSE));
if (edge_port->commandPending == TRUE) {
/* command timed out */
dbg("%s - command timed out", __FUNCTION__);
status = -EINVAL;
}
#endif
return status;
}
/*****************************************************************************
* send_cmd_write_baud_rate
* this function sends the proper command to change the baud rate of the
* specified port.
*****************************************************************************/
static int send_cmd_write_baud_rate (struct edgeport_port *edge_port, int baudRate)
{
unsigned char *cmdBuffer;
unsigned char *currCmd;
int cmdLen = 0;
int divisor;
int status;
unsigned char number = edge_port->port->number - edge_port->port->serial->minor;
dbg("%s - port = %d, baud = %d", __FUNCTION__, edge_port->port->number, baudRate);
status = calc_baud_rate_divisor (baudRate, &divisor);
if (status) {
dev_err(&edge_port->port->dev, "%s - bad baud rate\n", __FUNCTION__);
return status;
}
// Alloc memory for the string of commands.
cmdBuffer = kmalloc (0x100, GFP_ATOMIC);
if (!cmdBuffer) {
dev_err(&edge_port->port->dev, "%s - kmalloc(%d) failed.\n", __FUNCTION__, 0x100);
return -ENOMEM;
}
currCmd = cmdBuffer;
// Enable access to divisor latch
MAKE_CMD_WRITE_REG( &currCmd, &cmdLen, number, LCR, LCR_DL_ENABLE );
// Write the divisor itself
MAKE_CMD_WRITE_REG( &currCmd, &cmdLen, number, DLL, LOW8 (divisor) );
MAKE_CMD_WRITE_REG( &currCmd, &cmdLen, number, DLM, HIGH8(divisor) );
// Restore original value to disable access to divisor latch
MAKE_CMD_WRITE_REG( &currCmd, &cmdLen, number, LCR, edge_port->shadowLCR);
status = write_cmd_usb(edge_port, cmdBuffer, cmdLen );
if (status) {
/* something bad happened, let's free up the memory */
kfree (cmdBuffer);
}
return status;
}
/*****************************************************************************
* calc_baud_rate_divisor
* this function calculates the proper baud rate divisor for the specified
* baud rate.
*****************************************************************************/
static int calc_baud_rate_divisor (int baudrate, int *divisor)
{
int i;
__u16 custom;
dbg("%s - %d", __FUNCTION__, baudrate);
for (i = 0; i < ARRAY_SIZE(divisor_table); i++) {
if ( divisor_table[i].BaudRate == baudrate ) {
*divisor = divisor_table[i].Divisor;
return 0;
}
}
// We have tried all of the standard baud rates
// lets try to calculate the divisor for this baud rate
// Make sure the baud rate is reasonable
if (baudrate > 50 && baudrate < 230400) {
// get divisor
custom = (__u16)((230400L + baudrate/2) / baudrate);
*divisor = custom;
dbg("%s - Baud %d = %d\n", __FUNCTION__, baudrate, custom);
return 0;
}
return -1;
}
/*****************************************************************************
* send_cmd_write_uart_register
* this function builds up a uart register message and sends to to the device.
*****************************************************************************/
static int send_cmd_write_uart_register (struct edgeport_port *edge_port, __u8 regNum, __u8 regValue)
{
unsigned char *cmdBuffer;
unsigned char *currCmd;
unsigned long cmdLen = 0;
int status;
dbg("%s - write to %s register 0x%02x", (regNum == MCR) ? "MCR" : "LCR", __FUNCTION__, regValue);
// Alloc memory for the string of commands.
cmdBuffer = kmalloc (0x10, GFP_ATOMIC);
if (cmdBuffer == NULL ) {
return -ENOMEM;
}
currCmd = cmdBuffer;
// Build a cmd in the buffer to write the given register
MAKE_CMD_WRITE_REG (&currCmd, &cmdLen,
edge_port->port->number - edge_port->port->serial->minor,
regNum, regValue);
status = write_cmd_usb(edge_port, cmdBuffer, cmdLen);
if (status) {
/* something bad happened, let's free up the memory */
kfree (cmdBuffer);
}
return status;
}
/*****************************************************************************
* change_port_settings
* This routine is called to set the UART on the device to match the specified
* new settings.
*****************************************************************************/
#ifndef CMSPAR
#define CMSPAR 0
#endif
static void change_port_settings (struct edgeport_port *edge_port, struct termios *old_termios)
{
struct tty_struct *tty;
int baud;
unsigned cflag;
__u8 mask = 0xff;
__u8 lData;
__u8 lParity;
__u8 lStop;
__u8 rxFlow;
__u8 txFlow;
int status;
dbg("%s - port %d", __FUNCTION__, edge_port->port->number);
if ((!edge_port->open) &&
(!edge_port->openPending)) {
dbg("%s - port not opened", __FUNCTION__);
return;
}
tty = edge_port->port->tty;
if ((!tty) ||
(!tty->termios)) {
dbg("%s - no tty structures", __FUNCTION__);
return;
}
cflag = tty->termios->c_cflag;
switch (cflag & CSIZE) {
case CS5: lData = LCR_BITS_5; mask = 0x1f; dbg("%s - data bits = 5", __FUNCTION__); break;
case CS6: lData = LCR_BITS_6; mask = 0x3f; dbg("%s - data bits = 6", __FUNCTION__); break;
case CS7: lData = LCR_BITS_7; mask = 0x7f; dbg("%s - data bits = 7", __FUNCTION__); break;
default:
case CS8: lData = LCR_BITS_8; dbg("%s - data bits = 8", __FUNCTION__); break;
}
lParity = LCR_PAR_NONE;
if (cflag & PARENB) {
if (cflag & CMSPAR) {
if (cflag & PARODD) {
lParity = LCR_PAR_MARK;
dbg("%s - parity = mark", __FUNCTION__);
} else {
lParity = LCR_PAR_SPACE;
dbg("%s - parity = space", __FUNCTION__);
}
} else if (cflag & PARODD) {
lParity = LCR_PAR_ODD;
dbg("%s - parity = odd", __FUNCTION__);
} else {
lParity = LCR_PAR_EVEN;
dbg("%s - parity = even", __FUNCTION__);
}
} else {
dbg("%s - parity = none", __FUNCTION__);
}
if (cflag & CSTOPB) {
lStop = LCR_STOP_2;
dbg("%s - stop bits = 2", __FUNCTION__);
} else {
lStop = LCR_STOP_1;
dbg("%s - stop bits = 1", __FUNCTION__);
}
/* figure out the flow control settings */
rxFlow = txFlow = 0x00;
if (cflag & CRTSCTS) {
rxFlow |= IOSP_RX_FLOW_RTS;
txFlow |= IOSP_TX_FLOW_CTS;
dbg("%s - RTS/CTS is enabled", __FUNCTION__);
} else {
dbg("%s - RTS/CTS is disabled", __FUNCTION__);
}
/* if we are implementing XON/XOFF, set the start and stop character in the device */
if (I_IXOFF(tty) || I_IXON(tty)) {
unsigned char stop_char = STOP_CHAR(tty);
unsigned char start_char = START_CHAR(tty);
send_iosp_ext_cmd (edge_port, IOSP_CMD_SET_XON_CHAR, start_char);
send_iosp_ext_cmd (edge_port, IOSP_CMD_SET_XOFF_CHAR, stop_char);
/* if we are implementing INBOUND XON/XOFF */
if (I_IXOFF(tty)) {
rxFlow |= IOSP_RX_FLOW_XON_XOFF;
dbg("%s - INBOUND XON/XOFF is enabled, XON = %2x, XOFF = %2x", __FUNCTION__, start_char, stop_char);
} else {
dbg("%s - INBOUND XON/XOFF is disabled", __FUNCTION__);
}
/* if we are implementing OUTBOUND XON/XOFF */
if (I_IXON(tty)) {
txFlow |= IOSP_TX_FLOW_XON_XOFF;
dbg("%s - OUTBOUND XON/XOFF is enabled, XON = %2x, XOFF = %2x", __FUNCTION__, start_char, stop_char);
} else {
dbg("%s - OUTBOUND XON/XOFF is disabled", __FUNCTION__);
}
}
/* Set flow control to the configured value */
send_iosp_ext_cmd (edge_port, IOSP_CMD_SET_RX_FLOW, rxFlow);
send_iosp_ext_cmd (edge_port, IOSP_CMD_SET_TX_FLOW, txFlow);
edge_port->shadowLCR &= ~(LCR_BITS_MASK | LCR_STOP_MASK | LCR_PAR_MASK);
edge_port->shadowLCR |= (lData | lParity | lStop);
edge_port->validDataMask = mask;
/* Send the updated LCR value to the EdgePort */
status = send_cmd_write_uart_register(edge_port, LCR, edge_port->shadowLCR);
if (status != 0) {
return;
}
/* set up the MCR register and send it to the EdgePort */
edge_port->shadowMCR = MCR_MASTER_IE;
if (cflag & CBAUD) {
edge_port->shadowMCR |= (MCR_DTR | MCR_RTS);
}
status = send_cmd_write_uart_register(edge_port, MCR, edge_port->shadowMCR);
if (status != 0) {
return;
}
/* Determine divisor based on baud rate */
baud = tty_get_baud_rate(tty);
if (!baud) {
/* pick a default, any default... */
baud = 9600;
}
dbg("%s - baud rate = %d", __FUNCTION__, baud);
status = send_cmd_write_baud_rate (edge_port, baud);
return;
}
/****************************************************************************
* unicode_to_ascii
* Turns a string from Unicode into ASCII.
* Doesn't do a good job with any characters that are outside the normal
* ASCII range, but it's only for debugging...
* NOTE: expects the unicode in LE format
****************************************************************************/
static void unicode_to_ascii(char *string, int buflen, __le16 *unicode, int unicode_size)
{
int i;
if (buflen <= 0) /* never happens, but... */
return;
--buflen; /* space for nul */
for (i = 0; i < unicode_size; i++) {
if (i >= buflen)
break;
string[i] = (char)(le16_to_cpu(unicode[i]));
}
string[i] = 0x00;
}
/****************************************************************************
* get_manufacturing_desc
* reads in the manufacturing descriptor and stores it into the serial
* structure.
****************************************************************************/
static void get_manufacturing_desc (struct edgeport_serial *edge_serial)
{
int response;
dbg("getting manufacturer descriptor");
response = rom_read (edge_serial->serial, (EDGE_MANUF_DESC_ADDR & 0xffff0000) >> 16,
(__u16)(EDGE_MANUF_DESC_ADDR & 0x0000ffff), EDGE_MANUF_DESC_LEN,
(__u8 *)(&edge_serial->manuf_descriptor));
if (response < 1) {
dev_err(&edge_serial->serial->dev->dev, "error in getting manufacturer descriptor\n");
} else {
char string[30];
dbg("**Manufacturer Descriptor");
dbg(" RomSize: %dK", edge_serial->manuf_descriptor.RomSize);
dbg(" RamSize: %dK", edge_serial->manuf_descriptor.RamSize);
dbg(" CpuRev: %d", edge_serial->manuf_descriptor.CpuRev);
dbg(" BoardRev: %d", edge_serial->manuf_descriptor.BoardRev);
dbg(" NumPorts: %d", edge_serial->manuf_descriptor.NumPorts);
dbg(" DescDate: %d/%d/%d", edge_serial->manuf_descriptor.DescDate[0], edge_serial->manuf_descriptor.DescDate[1], edge_serial->manuf_descriptor.DescDate[2]+1900);
unicode_to_ascii(string, sizeof(string),
edge_serial->manuf_descriptor.SerialNumber,
edge_serial->manuf_descriptor.SerNumLength/2);
dbg(" SerialNumber: %s", string);
unicode_to_ascii(string, sizeof(string),
edge_serial->manuf_descriptor.AssemblyNumber,
edge_serial->manuf_descriptor.AssemblyNumLength/2);
dbg(" AssemblyNumber: %s", string);
unicode_to_ascii(string, sizeof(string),
edge_serial->manuf_descriptor.OemAssyNumber,
edge_serial->manuf_descriptor.OemAssyNumLength/2);
dbg(" OemAssyNumber: %s", string);
dbg(" UartType: %d", edge_serial->manuf_descriptor.UartType);
dbg(" IonPid: %d", edge_serial->manuf_descriptor.IonPid);
dbg(" IonConfig: %d", edge_serial->manuf_descriptor.IonConfig);
}
}
/****************************************************************************
* get_boot_desc
* reads in the bootloader descriptor and stores it into the serial
* structure.
****************************************************************************/
static void get_boot_desc (struct edgeport_serial *edge_serial)
{
int response;
dbg("getting boot descriptor");
response = rom_read (edge_serial->serial, (EDGE_BOOT_DESC_ADDR & 0xffff0000) >> 16,
(__u16)(EDGE_BOOT_DESC_ADDR & 0x0000ffff), EDGE_BOOT_DESC_LEN,
(__u8 *)(&edge_serial->boot_descriptor));
if (response < 1) {
dev_err(&edge_serial->serial->dev->dev, "error in getting boot descriptor\n");
} else {
dbg("**Boot Descriptor:");
dbg(" BootCodeLength: %d", le16_to_cpu(edge_serial->boot_descriptor.BootCodeLength));
dbg(" MajorVersion: %d", edge_serial->boot_descriptor.MajorVersion);
dbg(" MinorVersion: %d", edge_serial->boot_descriptor.MinorVersion);
dbg(" BuildNumber: %d", le16_to_cpu(edge_serial->boot_descriptor.BuildNumber));
dbg(" Capabilities: 0x%x", le16_to_cpu(edge_serial->boot_descriptor.Capabilities));
dbg(" UConfig0: %d", edge_serial->boot_descriptor.UConfig0);
dbg(" UConfig1: %d", edge_serial->boot_descriptor.UConfig1);
}
}
/****************************************************************************
* load_application_firmware
* This is called to load the application firmware to the device
****************************************************************************/
static void load_application_firmware (struct edgeport_serial *edge_serial)
{
struct edge_firmware_image_record *record;
unsigned char *firmware;
unsigned char *FirmwareImage;
int ImageSize;
int response;
switch (edge_serial->product_info.iDownloadFile) {
case EDGE_DOWNLOAD_FILE_I930:
dbg("downloading firmware version (930) %d.%d.%d",
OperationalCodeImageVersion_GEN1.MajorVersion,
OperationalCodeImageVersion_GEN1.MinorVersion,
OperationalCodeImageVersion_GEN1.BuildNumber);
firmware = &OperationalCodeImage_GEN1[0];
FirmwareImage = &OperationalCodeImage_GEN1[0];
ImageSize = sizeof(OperationalCodeImage_GEN1);
break;
case EDGE_DOWNLOAD_FILE_80251:
dbg("downloading firmware version (80251) %d.%d.%d",
OperationalCodeImageVersion_GEN2.MajorVersion,
OperationalCodeImageVersion_GEN2.MinorVersion,
OperationalCodeImageVersion_GEN2.BuildNumber);
firmware = &OperationalCodeImage_GEN2[0];
FirmwareImage = &OperationalCodeImage_GEN2[0];
ImageSize = sizeof(OperationalCodeImage_GEN2);
break;
case EDGE_DOWNLOAD_FILE_NONE:
dbg ("No download file specified, skipping download\n");
return;
default:
return;
}
for (;;) {
record = (struct edge_firmware_image_record *)firmware;
response = sram_write (edge_serial->serial, le16_to_cpu(record->ExtAddr), le16_to_cpu(record->Addr), le16_to_cpu(record->Len), &record->Data[0]);
if (response < 0) {
dev_err(&edge_serial->serial->dev->dev, "sram_write failed (%x, %x, %d)\n", le16_to_cpu(record->ExtAddr), le16_to_cpu(record->Addr), le16_to_cpu(record->Len));
break;
}
firmware += sizeof (struct edge_firmware_image_record) + le16_to_cpu(record->Len);
if (firmware >= &FirmwareImage[ImageSize]) {
break;
}
}
dbg("sending exec_dl_code");
response = usb_control_msg (edge_serial->serial->dev,
usb_sndctrlpipe(edge_serial->serial->dev, 0),
USB_REQUEST_ION_EXEC_DL_CODE,
0x40, 0x4000, 0x0001, NULL, 0, 3000);
return;
}
/****************************************************************************
* edge_startup
****************************************************************************/
static int edge_startup (struct usb_serial *serial)
{
struct edgeport_serial *edge_serial;
struct edgeport_port *edge_port;
struct usb_device *dev;
int i, j;
dev = serial->dev;
/* create our private serial structure */
edge_serial = kzalloc(sizeof(struct edgeport_serial), GFP_KERNEL);
if (edge_serial == NULL) {
dev_err(&serial->dev->dev, "%s - Out of memory\n", __FUNCTION__);
return -ENOMEM;
}
spin_lock_init(&edge_serial->es_lock);
edge_serial->serial = serial;
usb_set_serial_data(serial, edge_serial);
/* get the name for the device from the device */
i = get_string(dev, dev->descriptor.iManufacturer,
&edge_serial->name[0], MAX_NAME_LEN+1);
edge_serial->name[i++] = ' ';
get_string(dev, dev->descriptor.iProduct,
&edge_serial->name[i], MAX_NAME_LEN+2 - i);
dev_info(&serial->dev->dev, "%s detected\n", edge_serial->name);
/* get the manufacturing descriptor for this device */
get_manufacturing_desc (edge_serial);
/* get the boot descriptor */
get_boot_desc (edge_serial);
get_product_info(edge_serial);
/* set the number of ports from the manufacturing description */
/* serial->num_ports = serial->product_info.NumPorts; */
if (edge_serial->product_info.NumPorts != serial->num_ports) {
warn("%s - Device Reported %d serial ports vs core "
"thinking we have %d ports, email greg@kroah.com this info.",
__FUNCTION__, edge_serial->product_info.NumPorts,
serial->num_ports);
}
dbg("%s - time 1 %ld", __FUNCTION__, jiffies);
/* now load the application firmware into this device */
load_application_firmware (edge_serial);
dbg("%s - time 2 %ld", __FUNCTION__, jiffies);
/* Check current Edgeport EEPROM and update if necessary */
update_edgeport_E2PROM (edge_serial);
dbg("%s - time 3 %ld", __FUNCTION__, jiffies);
/* set the configuration to use #1 */
// dbg("set_configuration 1");
// usb_set_configuration (dev, 1);
/* we set up the pointers to the endpoints in the edge_open function,
* as the structures aren't created yet. */
/* set up our port private structures */
for (i = 0; i < serial->num_ports; ++i) {
edge_port = kmalloc (sizeof(struct edgeport_port), GFP_KERNEL);
if (edge_port == NULL) {
dev_err(&serial->dev->dev, "%s - Out of memory\n", __FUNCTION__);
for (j = 0; j < i; ++j) {
kfree (usb_get_serial_port_data(serial->port[j]));
usb_set_serial_port_data(serial->port[j], NULL);
}
usb_set_serial_data(serial, NULL);
kfree(edge_serial);
return -ENOMEM;
}
memset (edge_port, 0, sizeof(struct edgeport_port));
spin_lock_init(&edge_port->ep_lock);
edge_port->port = serial->port[i];
usb_set_serial_port_data(serial->port[i], edge_port);
}
return 0;
}
/****************************************************************************
* edge_shutdown
* This function is called whenever the device is removed from the usb bus.
****************************************************************************/
static void edge_shutdown (struct usb_serial *serial)
{
int i;
dbg("%s", __FUNCTION__);
/* stop reads and writes on all ports */
for (i=0; i < serial->num_ports; ++i) {
kfree (usb_get_serial_port_data(serial->port[i]));
usb_set_serial_port_data(serial->port[i], NULL);
}
kfree (usb_get_serial_data(serial));
usb_set_serial_data(serial, NULL);
}
/****************************************************************************
* edgeport_init
* This is called by the module subsystem, or on startup to initialize us
****************************************************************************/
static int __init edgeport_init(void)
{
int retval;
retval = usb_serial_register(&edgeport_2port_device);
if (retval)
goto failed_2port_device_register;
retval = usb_serial_register(&edgeport_4port_device);
if (retval)
goto failed_4port_device_register;
retval = usb_serial_register(&edgeport_8port_device);
if (retval)
goto failed_8port_device_register;
retval = usb_register(&io_driver);
if (retval)
goto failed_usb_register;
info(DRIVER_DESC " " DRIVER_VERSION);
return 0;
failed_usb_register:
usb_serial_deregister(&edgeport_8port_device);
failed_8port_device_register:
usb_serial_deregister(&edgeport_4port_device);
failed_4port_device_register:
usb_serial_deregister(&edgeport_2port_device);
failed_2port_device_register:
return retval;
}
/****************************************************************************
* edgeport_exit
* Called when the driver is about to be unloaded.
****************************************************************************/
static void __exit edgeport_exit (void)
{
usb_deregister (&io_driver);
usb_serial_deregister (&edgeport_2port_device);
usb_serial_deregister (&edgeport_4port_device);
usb_serial_deregister (&edgeport_8port_device);
}
module_init(edgeport_init);
module_exit(edgeport_exit);
/* Module information */
MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");
module_param(low_latency, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(low_latency, "Low latency enabled or not");