blob: 98fb9f360d83c464373036c050ff9382a1ff7372 [file] [log] [blame]
/*
* SPI driver for Micrel/Kendin KS8995M ethernet switch
*
* Copyright (C) 2008 Gabor Juhos <juhosg at openwrt.org>
*
* This file was based on: drivers/spi/at25.c
* Copyright (C) 2006 David Brownell
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/spi/spi.h>
#define DRV_VERSION "0.1.1"
#define DRV_DESC "Micrel KS8995 Ethernet switch SPI driver"
/* ------------------------------------------------------------------------ */
#define KS8995_REG_ID0 0x00 /* Chip ID0 */
#define KS8995_REG_ID1 0x01 /* Chip ID1 */
#define KS8995_REG_GC0 0x02 /* Global Control 0 */
#define KS8995_REG_GC1 0x03 /* Global Control 1 */
#define KS8995_REG_GC2 0x04 /* Global Control 2 */
#define KS8995_REG_GC3 0x05 /* Global Control 3 */
#define KS8995_REG_GC4 0x06 /* Global Control 4 */
#define KS8995_REG_GC5 0x07 /* Global Control 5 */
#define KS8995_REG_GC6 0x08 /* Global Control 6 */
#define KS8995_REG_GC7 0x09 /* Global Control 7 */
#define KS8995_REG_GC8 0x0a /* Global Control 8 */
#define KS8995_REG_GC9 0x0b /* Global Control 9 */
#define KS8995_REG_PC(p, r) ((0x10 * p) + r) /* Port Control */
#define KS8995_REG_PS(p, r) ((0x10 * p) + r + 0xe) /* Port Status */
#define KS8995_REG_TPC0 0x60 /* TOS Priority Control 0 */
#define KS8995_REG_TPC1 0x61 /* TOS Priority Control 1 */
#define KS8995_REG_TPC2 0x62 /* TOS Priority Control 2 */
#define KS8995_REG_TPC3 0x63 /* TOS Priority Control 3 */
#define KS8995_REG_TPC4 0x64 /* TOS Priority Control 4 */
#define KS8995_REG_TPC5 0x65 /* TOS Priority Control 5 */
#define KS8995_REG_TPC6 0x66 /* TOS Priority Control 6 */
#define KS8995_REG_TPC7 0x67 /* TOS Priority Control 7 */
#define KS8995_REG_MAC0 0x68 /* MAC address 0 */
#define KS8995_REG_MAC1 0x69 /* MAC address 1 */
#define KS8995_REG_MAC2 0x6a /* MAC address 2 */
#define KS8995_REG_MAC3 0x6b /* MAC address 3 */
#define KS8995_REG_MAC4 0x6c /* MAC address 4 */
#define KS8995_REG_MAC5 0x6d /* MAC address 5 */
#define KS8995_REG_IAC0 0x6e /* Indirect Access Control 0 */
#define KS8995_REG_IAC1 0x6f /* Indirect Access Control 0 */
#define KS8995_REG_IAD7 0x70 /* Indirect Access Data 7 */
#define KS8995_REG_IAD6 0x71 /* Indirect Access Data 6 */
#define KS8995_REG_IAD5 0x72 /* Indirect Access Data 5 */
#define KS8995_REG_IAD4 0x73 /* Indirect Access Data 4 */
#define KS8995_REG_IAD3 0x74 /* Indirect Access Data 3 */
#define KS8995_REG_IAD2 0x75 /* Indirect Access Data 2 */
#define KS8995_REG_IAD1 0x76 /* Indirect Access Data 1 */
#define KS8995_REG_IAD0 0x77 /* Indirect Access Data 0 */
#define KS8995_REGS_SIZE 0x80
#define ID1_CHIPID_M 0xf
#define ID1_CHIPID_S 4
#define ID1_REVISION_M 0x7
#define ID1_REVISION_S 1
#define ID1_START_SW 1 /* start the switch */
#define FAMILY_KS8995 0x95
#define CHIPID_M 0
#define KS8995_CMD_WRITE 0x02U
#define KS8995_CMD_READ 0x03U
#define KS8995_RESET_DELAY 10 /* usec */
struct ks8995_pdata {
/* not yet implemented */
};
struct ks8995_switch {
struct spi_device *spi;
struct mutex lock;
struct ks8995_pdata *pdata;
};
static inline u8 get_chip_id(u8 val)
{
return (val >> ID1_CHIPID_S) & ID1_CHIPID_M;
}
static inline u8 get_chip_rev(u8 val)
{
return (val >> ID1_REVISION_S) & ID1_REVISION_M;
}
/* ------------------------------------------------------------------------ */
static int ks8995_read(struct ks8995_switch *ks, char *buf,
unsigned offset, size_t count)
{
u8 cmd[2];
struct spi_transfer t[2];
struct spi_message m;
int err;
spi_message_init(&m);
memset(&t, 0, sizeof(t));
t[0].tx_buf = cmd;
t[0].len = sizeof(cmd);
spi_message_add_tail(&t[0], &m);
t[1].rx_buf = buf;
t[1].len = count;
spi_message_add_tail(&t[1], &m);
cmd[0] = KS8995_CMD_READ;
cmd[1] = offset;
mutex_lock(&ks->lock);
err = spi_sync(ks->spi, &m);
mutex_unlock(&ks->lock);
return err ? err : count;
}
static int ks8995_write(struct ks8995_switch *ks, char *buf,
unsigned offset, size_t count)
{
u8 cmd[2];
struct spi_transfer t[2];
struct spi_message m;
int err;
spi_message_init(&m);
memset(&t, 0, sizeof(t));
t[0].tx_buf = cmd;
t[0].len = sizeof(cmd);
spi_message_add_tail(&t[0], &m);
t[1].tx_buf = buf;
t[1].len = count;
spi_message_add_tail(&t[1], &m);
cmd[0] = KS8995_CMD_WRITE;
cmd[1] = offset;
mutex_lock(&ks->lock);
err = spi_sync(ks->spi, &m);
mutex_unlock(&ks->lock);
return err ? err : count;
}
static inline int ks8995_read_reg(struct ks8995_switch *ks, u8 addr, u8 *buf)
{
return (ks8995_read(ks, buf, addr, 1) != 1);
}
static inline int ks8995_write_reg(struct ks8995_switch *ks, u8 addr, u8 val)
{
char buf = val;
return (ks8995_write(ks, &buf, addr, 1) != 1);
}
/* ------------------------------------------------------------------------ */
static int ks8995_stop(struct ks8995_switch *ks)
{
return ks8995_write_reg(ks, KS8995_REG_ID1, 0);
}
static int ks8995_start(struct ks8995_switch *ks)
{
return ks8995_write_reg(ks, KS8995_REG_ID1, 1);
}
static int ks8995_reset(struct ks8995_switch *ks)
{
int err;
err = ks8995_stop(ks);
if (err)
return err;
udelay(KS8995_RESET_DELAY);
return ks8995_start(ks);
}
/* ------------------------------------------------------------------------ */
static ssize_t ks8995_registers_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
{
struct device *dev;
struct ks8995_switch *ks8995;
dev = container_of(kobj, struct device, kobj);
ks8995 = dev_get_drvdata(dev);
if (unlikely(off > KS8995_REGS_SIZE))
return 0;
if ((off + count) > KS8995_REGS_SIZE)
count = KS8995_REGS_SIZE - off;
if (unlikely(!count))
return count;
return ks8995_read(ks8995, buf, off, count);
}
static ssize_t ks8995_registers_write(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr, char *buf, loff_t off, size_t count)
{
struct device *dev;
struct ks8995_switch *ks8995;
dev = container_of(kobj, struct device, kobj);
ks8995 = dev_get_drvdata(dev);
if (unlikely(off >= KS8995_REGS_SIZE))
return -EFBIG;
if ((off + count) > KS8995_REGS_SIZE)
count = KS8995_REGS_SIZE - off;
if (unlikely(!count))
return count;
return ks8995_write(ks8995, buf, off, count);
}
static struct bin_attribute ks8995_registers_attr = {
.attr = {
.name = "registers",
.mode = S_IRUSR | S_IWUSR,
},
.size = KS8995_REGS_SIZE,
.read = ks8995_registers_read,
.write = ks8995_registers_write,
};
/* ------------------------------------------------------------------------ */
static int ks8995_probe(struct spi_device *spi)
{
struct ks8995_switch *ks;
struct ks8995_pdata *pdata;
u8 ids[2];
int err;
/* Chip description */
pdata = spi->dev.platform_data;
ks = kzalloc(sizeof(*ks), GFP_KERNEL);
if (!ks)
return -ENOMEM;
mutex_init(&ks->lock);
ks->pdata = pdata;
ks->spi = spi_dev_get(spi);
spi_set_drvdata(spi, ks);
spi->mode = SPI_MODE_0;
spi->bits_per_word = 8;
err = spi_setup(spi);
if (err) {
dev_err(&spi->dev, "spi_setup failed, err=%d\n", err);
goto err_drvdata;
}
err = ks8995_read(ks, ids, KS8995_REG_ID0, sizeof(ids));
if (err < 0) {
dev_err(&spi->dev, "unable to read id registers, err=%d\n",
err);
goto err_drvdata;
}
switch (ids[0]) {
case FAMILY_KS8995:
break;
default:
dev_err(&spi->dev, "unknown family id:%02x\n", ids[0]);
err = -ENODEV;
goto err_drvdata;
}
err = ks8995_reset(ks);
if (err)
goto err_drvdata;
err = sysfs_create_bin_file(&spi->dev.kobj, &ks8995_registers_attr);
if (err) {
dev_err(&spi->dev, "unable to create sysfs file, err=%d\n",
err);
goto err_drvdata;
}
dev_info(&spi->dev, "KS89%02X device found, Chip ID:%01x, "
"Revision:%01x\n", ids[0],
get_chip_id(ids[1]), get_chip_rev(ids[1]));
return 0;
err_drvdata:
kfree(ks);
return err;
}
static int ks8995_remove(struct spi_device *spi)
{
struct ks8995_data *ks8995;
ks8995 = spi_get_drvdata(spi);
sysfs_remove_bin_file(&spi->dev.kobj, &ks8995_registers_attr);
kfree(ks8995);
return 0;
}
/* ------------------------------------------------------------------------ */
static struct spi_driver ks8995_driver = {
.driver = {
.name = "spi-ks8995",
.owner = THIS_MODULE,
},
.probe = ks8995_probe,
.remove = ks8995_remove,
};
module_spi_driver(ks8995_driver);
MODULE_DESCRIPTION(DRV_DESC);
MODULE_VERSION(DRV_VERSION);
MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
MODULE_LICENSE("GPL v2");