greybus: uart-gb: now builds, more framework added
diff --git a/drivers/staging/greybus/uart-gb.c b/drivers/staging/greybus/uart-gb.c
index 792536c..13a23cd 100644
--- a/drivers/staging/greybus/uart-gb.c
+++ b/drivers/staging/greybus/uart-gb.c
@@ -1,18 +1,27 @@
/*
- * I2C bridge driver for the Greybus "generic" I2C module.
+ * UART driver for the Greybus "generic" UART module.
*
* Copyright 2014 Google Inc.
*
* Released under the GPLv2 only.
+ *
+ * Heavily based on drivers/usb/class/cdc-acm.c and
+ * drivers/usb/serial/usb-serial.c.
*/
#include <linux/kernel.h>
+#include <linux/errno.h>
#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/mutex.h>
#include <linux/tty.h>
#include <linux/serial.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
+#include <linux/serial.h>
#include <linux/idr.h>
#include "greybus.h"
@@ -27,9 +36,14 @@
unsigned char clocal;
unsigned int throttled:1;
unsigned int throttle_req:1;
+ bool disconnected;
+ int writesize; // FIXME - set this somehow.
spinlock_t read_lock;
spinlock_t write_lock;
- // FIXME locking!!!
+ struct async_icount iocount;
+ struct async_icount oldcount;
+ wait_queue_head_t wioctl;
+ struct mutex mutex;
};
static const struct greybus_device_id id_table[] = {
@@ -47,6 +61,16 @@
mutex_lock(&table_lock);
gb_tty = idr_find(&tty_minors, minor);
+ if (gb_tty) {
+ mutex_lock(&gb_tty->mutex);
+ if (gb_tty->disconnected) {
+ mutex_unlock(&gb_tty->mutex);
+ gb_tty = NULL;
+ } else {
+ tty_port_get(&gb_tty->port);
+ mutex_unlock(&gb_tty->mutex);
+ }
+ }
mutex_unlock(&table_lock);
return gb_tty;
}
@@ -123,7 +147,7 @@
static int gb_tty_write(struct tty_struct *tty, const unsigned char *buf,
int count)
{
- struct gb_tty *gb_tty = tty->driver_data;
+// struct gb_tty *gb_tty = tty->driver_data;
// FIXME - actually implement...
@@ -132,7 +156,7 @@
static int gb_tty_write_room(struct tty_struct *tty)
{
- struct gb_tty *gb_tty = tty->driver_data;
+// struct gb_tty *gb_tty = tty->driver_data;
// FIXME - how much do we want to say we have room for?
return 0;
@@ -140,12 +164,43 @@
static int gb_tty_chars_in_buffer(struct tty_struct *tty)
{
- struct gb_tty *gb_tty = tty->driver_data;
+// struct gb_tty *gb_tty = tty->driver_data;
// FIXME - how many left to send?
return 0;
}
+static int gb_tty_break_ctl(struct tty_struct *tty, int state)
+{
+// struct gb_tty *gb_tty = tty->driver_data;
+
+ // FIXME - send a break, if asked to...
+ return 0;
+}
+
+static void gb_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
+{
+ // FIXME - is this it???
+ tty_termios_copy_hw(&tty->termios, old);
+}
+
+static int gb_tty_tiocmget(struct tty_struct *tty)
+{
+// struct gb_tty *gb_tty = tty->driver_data;
+
+ // FIXME - get some tiocms!
+ return 0;
+}
+
+static int gb_tty_tiocmset(struct tty_struct *tty, unsigned int set,
+ unsigned int clear)
+{
+// struct gb_tty *gb_tty = tty->driver_data;
+
+ // FIXME - set some tiocms!
+ return 0;
+}
+
static void gb_tty_throttle(struct tty_struct *tty)
{
struct gb_tty *gb_tty = tty->driver_data;
@@ -171,6 +226,148 @@
}
}
+static int get_serial_info(struct gb_tty *gb_tty,
+ struct serial_struct __user *info)
+{
+ struct serial_struct tmp;
+
+ if (!info)
+ return -EINVAL;
+
+ memset(&tmp, 0, sizeof(tmp));
+ tmp.flags = ASYNC_LOW_LATENCY;
+ tmp.xmit_fifo_size = gb_tty->writesize;
+ tmp.baud_base = 0; // FIXME
+ tmp.close_delay = gb_tty->port.close_delay / 10;
+ tmp.closing_wait = gb_tty->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
+ ASYNC_CLOSING_WAIT_NONE : gb_tty->port.closing_wait / 10;
+
+ if (copy_to_user(info, &tmp, sizeof(tmp)))
+ return -EFAULT;
+ else
+ return 0;
+}
+
+static int set_serial_info(struct gb_tty *gb_tty,
+ struct serial_struct __user *newinfo)
+{
+ struct serial_struct new_serial;
+ unsigned int closing_wait;
+ unsigned int close_delay;
+ int retval;
+
+ if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
+ return -EFAULT;
+
+ close_delay = new_serial.close_delay * 10;
+ closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
+ ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
+
+ mutex_lock(&gb_tty->port.mutex);
+ if (!capable(CAP_SYS_ADMIN)) {
+ if ((close_delay != gb_tty->port.close_delay) ||
+ (closing_wait != gb_tty->port.closing_wait))
+ retval = -EPERM;
+ else
+ retval = -EOPNOTSUPP;
+ } else {
+ gb_tty->port.close_delay = close_delay;
+ gb_tty->port.closing_wait = closing_wait;
+ }
+ mutex_unlock(&gb_tty->port.mutex);
+ return retval;
+}
+
+static int wait_serial_change(struct gb_tty *gb_tty, unsigned long arg)
+{
+ int retval = 0;
+ DECLARE_WAITQUEUE(wait, current);
+ struct async_icount old;
+ struct async_icount new;
+
+ if (arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD))
+ return -EINVAL;
+
+ do {
+ spin_lock_irq(&gb_tty->read_lock);
+ old = gb_tty->oldcount;
+ new = gb_tty->iocount;
+ gb_tty->oldcount = new;
+ spin_lock_irq(&gb_tty->read_lock);
+
+ if ((arg & TIOCM_DSR) && (old.dsr != new.dsr))
+ break;
+ if ((arg & TIOCM_CD) && (old.dcd != new.dcd))
+ break;
+ if ((arg & TIOCM_RI) && (old.rng != new.rng))
+ break;
+
+ add_wait_queue(&gb_tty->wioctl, &wait);
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule();
+ remove_wait_queue(&gb_tty->wioctl, &wait);
+ if (gb_tty->disconnected) {
+ if (arg & TIOCM_CD)
+ break;
+ else
+ retval = -ENODEV;
+ } else {
+ if (signal_pending(current))
+ retval = -ERESTARTSYS;
+ }
+ } while (!retval);
+
+ return retval;
+}
+
+static int get_serial_usage(struct gb_tty *gb_tty,
+ struct serial_icounter_struct __user *count)
+{
+ struct serial_icounter_struct icount;
+ int retval = 0;
+
+ memset(&icount, 0, sizeof(icount));
+ icount.dsr = gb_tty->iocount.dsr;
+ icount.rng = gb_tty->iocount.rng;
+ icount.dcd = gb_tty->iocount.dcd;
+ icount.frame = gb_tty->iocount.frame;
+ icount.overrun = gb_tty->iocount.overrun;
+ icount.parity = gb_tty->iocount.parity;
+ icount.brk = gb_tty->iocount.brk;
+
+ if (copy_to_user(count, &icount, sizeof(icount)) > 0)
+ retval = -EFAULT;
+
+ return retval;
+}
+
+static int gb_tty_ioctl(struct tty_struct *tty, unsigned int cmd,
+ unsigned long arg)
+{
+ struct gb_tty *gb_tty = tty->driver_data;
+ int retval = -ENOIOCTLCMD;
+
+ switch (cmd) {
+ case TIOCGSERIAL:
+ retval = get_serial_info(gb_tty,
+ (struct serial_struct __user *)arg);
+ break;
+ case TIOCSSERIAL:
+ retval = set_serial_info(gb_tty,
+ (struct serial_struct __user *)arg);
+ break;
+ case TIOCMIWAIT:
+ retval = wait_serial_change(gb_tty, arg);
+ break;
+ case TIOCGICOUNT:
+ retval = get_serial_usage(gb_tty,
+ (struct serial_icounter_struct __user *)arg);
+ break;
+ }
+
+ return retval;
+}
+
static const struct tty_operations gb_ops = {
.install = gb_tty_install,
@@ -212,6 +409,8 @@
gb_tty->gdev = gdev;
spin_lock_init(&gb_tty->write_lock);
spin_lock_init(&gb_tty->read_lock);
+ init_waitqueue_head(&gb_tty->wioctl);
+ mutex_init(&gb_tty->mutex);
/* FIXME - allocate gb buffers */
@@ -235,6 +434,16 @@
struct gb_tty *gb_tty = greybus_get_drvdata(gdev);
struct tty_struct *tty;
+ if (!gb_tty)
+ return;
+
+ mutex_lock(&gb_tty->mutex);
+ gb_tty->disconnected = true;
+
+ wake_up_all(&gb_tty->wioctl);
+ greybus_set_drvdata(gdev, NULL);
+ mutex_unlock(&gb_tty->mutex);
+
tty = tty_port_tty_get(&gb_tty->port);
if (tty) {
tty_vhangup(tty);
@@ -244,6 +453,8 @@
tty_unregister_device(gb_tty_driver, gb_tty->minor);
+ /* FIXME - free transmit / recieve buffers */
+
tty_port_put(&gb_tty->port);
}