linux/drivers/watchdog/ziirave_wdt.c

754 lines
19 KiB
C
Raw Normal View History

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 Based on 3 normalized pattern(s): 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 this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details 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 [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details 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 [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-27 08:55:06 +02:00
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2015 Zodiac Inflight Innovations
*
* Author: Martyn Welch <martyn.welch@collabora.co.uk>
*
* Based on twl4030_wdt.c by Timo Kokkonen <timo.t.kokkonen at nokia.com>:
*
* Copyright (C) Nokia Corporation
*/
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/ihex.h>
#include <linux/firmware.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/types.h>
#include <linux/version.h>
#include <linux/watchdog.h>
#define ZIIRAVE_TIMEOUT_MIN 3
#define ZIIRAVE_TIMEOUT_MAX 255
#define ZIIRAVE_PING_VALUE 0x0
#define ZIIRAVE_STATE_INITIAL 0x0
#define ZIIRAVE_STATE_OFF 0x1
#define ZIIRAVE_STATE_ON 0x2
#define ZIIRAVE_FW_NAME "ziirave_wdt.fw"
static char *ziirave_reasons[] = {"power cycle", "hw watchdog", NULL, NULL,
"host request", NULL, "illegal configuration",
"illegal instruction", "illegal trap",
"unknown"};
#define ZIIRAVE_WDT_FIRM_VER_MAJOR 0x1
#define ZIIRAVE_WDT_BOOT_VER_MAJOR 0x3
#define ZIIRAVE_WDT_RESET_REASON 0x5
#define ZIIRAVE_WDT_STATE 0x6
#define ZIIRAVE_WDT_TIMEOUT 0x7
#define ZIIRAVE_WDT_TIME_LEFT 0x8
#define ZIIRAVE_WDT_PING 0x9
#define ZIIRAVE_WDT_RESET_DURATION 0xa
#define ZIIRAVE_FIRM_PKT_TOTAL_SIZE 20
#define ZIIRAVE_FIRM_PKT_DATA_SIZE 16
#define ZIIRAVE_FIRM_FLASH_MEMORY_START 0x1600
#define ZIIRAVE_FIRM_FLASH_MEMORY_END 0x2bbf
/* Received and ready for next Download packet. */
#define ZIIRAVE_FIRM_DOWNLOAD_ACK 1
/* Currently writing to flash. Retry Download status in a moment! */
#define ZIIRAVE_FIRM_DOWNLOAD_BUSY 2
/* Wait for ACK timeout in ms */
#define ZIIRAVE_FIRM_WAIT_FOR_ACK_TIMEOUT 50
/* Firmware commands */
#define ZIIRAVE_CMD_DOWNLOAD_START 0x10
#define ZIIRAVE_CMD_DOWNLOAD_END 0x11
#define ZIIRAVE_CMD_DOWNLOAD_SET_READ_ADDR 0x12
#define ZIIRAVE_CMD_DOWNLOAD_READ_BYTE 0x13
#define ZIIRAVE_CMD_RESET_PROCESSOR 0x0b
#define ZIIRAVE_CMD_JUMP_TO_BOOTLOADER 0x0c
#define ZIIRAVE_CMD_DOWNLOAD_PACKET 0x0e
struct ziirave_wdt_rev {
unsigned char major;
unsigned char minor;
};
struct ziirave_wdt_data {
struct mutex sysfs_mutex;
struct watchdog_device wdd;
struct ziirave_wdt_rev bootloader_rev;
struct ziirave_wdt_rev firmware_rev;
int reset_reason;
};
static int wdt_timeout;
module_param(wdt_timeout, int, 0);
MODULE_PARM_DESC(wdt_timeout, "Watchdog timeout in seconds");
static int reset_duration;
module_param(reset_duration, int, 0);
MODULE_PARM_DESC(reset_duration,
"Watchdog reset pulse duration in milliseconds");
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
static int ziirave_wdt_revision(struct i2c_client *client,
struct ziirave_wdt_rev *rev, u8 command)
{
int ret;
ret = i2c_smbus_read_byte_data(client, command);
if (ret < 0)
return ret;
rev->major = ret;
ret = i2c_smbus_read_byte_data(client, command + 1);
if (ret < 0)
return ret;
rev->minor = ret;
return 0;
}
static int ziirave_wdt_set_state(struct watchdog_device *wdd, int state)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_STATE, state);
}
static int ziirave_wdt_start(struct watchdog_device *wdd)
{
return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_ON);
}
static int ziirave_wdt_stop(struct watchdog_device *wdd)
{
return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_OFF);
}
static int ziirave_wdt_ping(struct watchdog_device *wdd)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_PING,
ZIIRAVE_PING_VALUE);
}
static int ziirave_wdt_set_timeout(struct watchdog_device *wdd,
unsigned int timeout)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
int ret;
ret = i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_TIMEOUT, timeout);
if (!ret)
wdd->timeout = timeout;
return ret;
}
static unsigned int ziirave_wdt_get_timeleft(struct watchdog_device *wdd)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
int ret;
ret = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_TIME_LEFT);
if (ret < 0)
ret = 0;
return ret;
}
static int ziirave_firm_wait_for_ack(struct watchdog_device *wdd)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
int ret;
unsigned long timeout;
timeout = jiffies + msecs_to_jiffies(ZIIRAVE_FIRM_WAIT_FOR_ACK_TIMEOUT);
do {
if (time_after(jiffies, timeout))
return -ETIMEDOUT;
usleep_range(5000, 10000);
ret = i2c_smbus_read_byte(client);
if (ret < 0) {
dev_err(&client->dev, "Failed to read byte\n");
return ret;
}
} while (ret == ZIIRAVE_FIRM_DOWNLOAD_BUSY);
return ret == ZIIRAVE_FIRM_DOWNLOAD_ACK ? 0 : -EIO;
}
static int ziirave_firm_set_read_addr(struct watchdog_device *wdd, u16 addr)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
u8 address[2];
address[0] = addr & 0xff;
address[1] = (addr >> 8) & 0xff;
return i2c_smbus_write_block_data(client,
ZIIRAVE_CMD_DOWNLOAD_SET_READ_ADDR,
ARRAY_SIZE(address), address);
}
static int ziirave_firm_write_block_data(struct watchdog_device *wdd,
u8 command, u8 length, const u8 *data,
bool wait_for_ack)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
int ret;
ret = i2c_smbus_write_block_data(client, command, length, data);
if (ret) {
dev_err(&client->dev,
"Failed to send command 0x%02x: %d\n", command, ret);
return ret;
}
if (wait_for_ack)
ret = ziirave_firm_wait_for_ack(wdd);
return ret;
}
static int ziirave_firm_write_byte(struct watchdog_device *wdd, u8 command,
u8 byte, bool wait_for_ack)
{
return ziirave_firm_write_block_data(wdd, command, 1, &byte,
wait_for_ack);
}
/*
* ziirave_firm_write_pkt() - Build and write a firmware packet
*
* A packet to send to the firmware is composed by following bytes:
* Length | Addr0 | Addr1 | Data0 .. Data15 | Checksum |
* Where,
* Length: A data byte containing the length of the data.
* Addr0: Low byte of the address.
* Addr1: High byte of the address.
* Data0 .. Data15: Array of 16 bytes of data.
* Checksum: Checksum byte to verify data integrity.
*/
static int ziirave_firm_write_pkt(struct watchdog_device *wdd,
const struct ihex_binrec *rec)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
u8 i, checksum = 0, packet[ZIIRAVE_FIRM_PKT_TOTAL_SIZE];
int ret;
u16 addr;
memset(packet, 0, ARRAY_SIZE(packet));
/* Packet length */
packet[0] = (u8)be16_to_cpu(rec->len);
/* Packet address */
addr = (be32_to_cpu(rec->addr) & 0xffff) >> 1;
packet[1] = addr & 0xff;
packet[2] = (addr & 0xff00) >> 8;
/* Packet data */
if (be16_to_cpu(rec->len) > ZIIRAVE_FIRM_PKT_DATA_SIZE)
return -EMSGSIZE;
memcpy(packet + 3, rec->data, be16_to_cpu(rec->len));
/* Packet checksum */
for (i = 0; i < ZIIRAVE_FIRM_PKT_TOTAL_SIZE - 1; i++)
checksum += packet[i];
packet[ZIIRAVE_FIRM_PKT_TOTAL_SIZE - 1] = checksum;
ret = ziirave_firm_write_block_data(wdd, ZIIRAVE_CMD_DOWNLOAD_PACKET,
ARRAY_SIZE(packet), packet, true);
if (ret)
dev_err(&client->dev,
"Failed to write firmware packet at address 0x%04x: %d\n",
addr, ret);
return ret;
}
static int ziirave_firm_verify(struct watchdog_device *wdd,
const struct firmware *fw)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
const struct ihex_binrec *rec;
int i, ret;
u8 data[ZIIRAVE_FIRM_PKT_DATA_SIZE];
u16 addr;
for (rec = (void *)fw->data; rec; rec = ihex_next_binrec(rec)) {
/* Zero length marks end of records */
if (!be16_to_cpu(rec->len))
break;
addr = (be32_to_cpu(rec->addr) & 0xffff) >> 1;
if (addr < ZIIRAVE_FIRM_FLASH_MEMORY_START ||
addr > ZIIRAVE_FIRM_FLASH_MEMORY_END)
continue;
ret = ziirave_firm_set_read_addr(wdd, addr);
if (ret) {
dev_err(&client->dev,
"Failed to send SET_READ_ADDR command: %d\n",
ret);
return ret;
}
for (i = 0; i < ARRAY_SIZE(data); i++) {
ret = i2c_smbus_read_byte_data(client,
ZIIRAVE_CMD_DOWNLOAD_READ_BYTE);
if (ret < 0) {
dev_err(&client->dev,
"Failed to READ DATA: %d\n", ret);
return ret;
}
data[i] = ret;
}
if (memcmp(data, rec->data, be16_to_cpu(rec->len))) {
dev_err(&client->dev,
"Firmware mismatch at address 0x%04x\n", addr);
return -EINVAL;
}
}
return 0;
}
static int ziirave_firm_upload(struct watchdog_device *wdd,
const struct firmware *fw)
{
struct i2c_client *client = to_i2c_client(wdd->parent);
int ret, words_till_page_break;
const struct ihex_binrec *rec;
struct ihex_binrec *rec_new;
ret = ziirave_firm_write_byte(wdd, ZIIRAVE_CMD_JUMP_TO_BOOTLOADER, 1,
false);
if (ret)
return ret;
msleep(500);
ret = ziirave_firm_write_byte(wdd, ZIIRAVE_CMD_DOWNLOAD_START, 1, true);
if (ret)
return ret;
msleep(500);
for (rec = (void *)fw->data; rec; rec = ihex_next_binrec(rec)) {
/* Zero length marks end of records */
if (!be16_to_cpu(rec->len))
break;
/* Check max data size */
if (be16_to_cpu(rec->len) > ZIIRAVE_FIRM_PKT_DATA_SIZE) {
dev_err(&client->dev, "Firmware packet too long (%d)\n",
be16_to_cpu(rec->len));
return -EMSGSIZE;
}
/* Calculate words till page break */
words_till_page_break = (64 - ((be32_to_cpu(rec->addr) >> 1) &
0x3f));
if ((be16_to_cpu(rec->len) >> 1) > words_till_page_break) {
/*
* Data in passes page boundary, so we need to split in
* two blocks of data. Create a packet with the first
* block of data.
*/
rec_new = kzalloc(sizeof(struct ihex_binrec) +
(words_till_page_break << 1),
GFP_KERNEL);
if (!rec_new)
return -ENOMEM;
rec_new->len = cpu_to_be16(words_till_page_break << 1);
rec_new->addr = rec->addr;
memcpy(rec_new->data, rec->data,
be16_to_cpu(rec_new->len));
ret = ziirave_firm_write_pkt(wdd, rec_new);
kfree(rec_new);
if (ret)
return ret;
/* Create a packet with the second block of data */
rec_new = kzalloc(sizeof(struct ihex_binrec) +
be16_to_cpu(rec->len) -
(words_till_page_break << 1),
GFP_KERNEL);
if (!rec_new)
return -ENOMEM;
/* Remaining bytes */
rec_new->len = rec->len -
cpu_to_be16(words_till_page_break << 1);
rec_new->addr = cpu_to_be32(be32_to_cpu(rec->addr) +
(words_till_page_break << 1));
memcpy(rec_new->data,
rec->data + (words_till_page_break << 1),
be16_to_cpu(rec_new->len));
ret = ziirave_firm_write_pkt(wdd, rec_new);
kfree(rec_new);
if (ret)
return ret;
} else {
ret = ziirave_firm_write_pkt(wdd, rec);
if (ret)
return ret;
}
}
/* For end of download, the length field will be set to 0 */
rec_new = kzalloc(sizeof(struct ihex_binrec) + 1, GFP_KERNEL);
if (!rec_new)
return -ENOMEM;
ret = ziirave_firm_write_pkt(wdd, rec_new);
kfree(rec_new);
if (ret) {
dev_err(&client->dev, "Failed to send EMPTY packet: %d\n", ret);
return ret;
}
/* This sleep seems to be required */
msleep(20);
/* Start firmware verification */
ret = ziirave_firm_verify(wdd, fw);
if (ret) {
dev_err(&client->dev,
"Failed to verify firmware: %d\n", ret);
return ret;
}
/* End download operation */
ret = ziirave_firm_write_byte(wdd, ZIIRAVE_CMD_DOWNLOAD_END, 1, false);
if (ret)
return ret;
/* Reset the processor */
ret = ziirave_firm_write_byte(wdd, ZIIRAVE_CMD_RESET_PROCESSOR, 1,
false);
if (ret)
return ret;
msleep(500);
return 0;
}
static const struct watchdog_info ziirave_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
.identity = "Zodiac RAVE Watchdog",
};
static const struct watchdog_ops ziirave_wdt_ops = {
.owner = THIS_MODULE,
.start = ziirave_wdt_start,
.stop = ziirave_wdt_stop,
.ping = ziirave_wdt_ping,
.set_timeout = ziirave_wdt_set_timeout,
.get_timeleft = ziirave_wdt_get_timeleft,
};
static ssize_t ziirave_wdt_sysfs_show_firm(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct i2c_client *client = to_i2c_client(dev->parent);
struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
int ret;
ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
if (ret)
return ret;
ret = sprintf(buf, "02.%02u.%02u", w_priv->firmware_rev.major,
w_priv->firmware_rev.minor);
mutex_unlock(&w_priv->sysfs_mutex);
return ret;
}
static DEVICE_ATTR(firmware_version, S_IRUGO, ziirave_wdt_sysfs_show_firm,
NULL);
static ssize_t ziirave_wdt_sysfs_show_boot(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct i2c_client *client = to_i2c_client(dev->parent);
struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
int ret;
ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
if (ret)
return ret;
ret = sprintf(buf, "01.%02u.%02u", w_priv->bootloader_rev.major,
w_priv->bootloader_rev.minor);
mutex_unlock(&w_priv->sysfs_mutex);
return ret;
}
static DEVICE_ATTR(bootloader_version, S_IRUGO, ziirave_wdt_sysfs_show_boot,
NULL);
static ssize_t ziirave_wdt_sysfs_show_reason(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct i2c_client *client = to_i2c_client(dev->parent);
struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
int ret;
ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
if (ret)
return ret;
ret = sprintf(buf, "%s", ziirave_reasons[w_priv->reset_reason]);
mutex_unlock(&w_priv->sysfs_mutex);
return ret;
}
static DEVICE_ATTR(reset_reason, S_IRUGO, ziirave_wdt_sysfs_show_reason,
NULL);
static ssize_t ziirave_wdt_sysfs_store_firm(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev->parent);
struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
const struct firmware *fw;
int err;
err = request_ihex_firmware(&fw, ZIIRAVE_FW_NAME, dev);
if (err) {
dev_err(&client->dev, "Failed to request ihex firmware\n");
return err;
}
err = mutex_lock_interruptible(&w_priv->sysfs_mutex);
if (err)
goto release_firmware;
err = ziirave_firm_upload(&w_priv->wdd, fw);
if (err) {
dev_err(&client->dev, "The firmware update failed: %d\n", err);
goto unlock_mutex;
}
/* Update firmware version */
err = ziirave_wdt_revision(client, &w_priv->firmware_rev,
ZIIRAVE_WDT_FIRM_VER_MAJOR);
if (err) {
dev_err(&client->dev, "Failed to read firmware version: %d\n",
err);
goto unlock_mutex;
}
dev_info(&client->dev, "Firmware updated to version 02.%02u.%02u\n",
w_priv->firmware_rev.major, w_priv->firmware_rev.minor);
/* Restore the watchdog timeout */
err = ziirave_wdt_set_timeout(&w_priv->wdd, w_priv->wdd.timeout);
if (err)
dev_err(&client->dev, "Failed to set timeout: %d\n", err);
unlock_mutex:
mutex_unlock(&w_priv->sysfs_mutex);
release_firmware:
release_firmware(fw);
return err ? err : count;
}
static DEVICE_ATTR(update_firmware, S_IWUSR, NULL,
ziirave_wdt_sysfs_store_firm);
static struct attribute *ziirave_wdt_attrs[] = {
&dev_attr_firmware_version.attr,
&dev_attr_bootloader_version.attr,
&dev_attr_reset_reason.attr,
&dev_attr_update_firmware.attr,
NULL
};
ATTRIBUTE_GROUPS(ziirave_wdt);
static int ziirave_wdt_init_duration(struct i2c_client *client)
{
int ret;
if (!reset_duration) {
/* See if the reset pulse duration is provided in an of_node */
if (!client->dev.of_node)
ret = -ENODEV;
else
ret = of_property_read_u32(client->dev.of_node,
"reset-duration-ms",
&reset_duration);
if (ret) {
dev_info(&client->dev,
"Unable to set reset pulse duration, using default\n");
return 0;
}
}
if (reset_duration < 1 || reset_duration > 255)
return -EINVAL;
dev_info(&client->dev, "Setting reset duration to %dms",
reset_duration);
return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_RESET_DURATION,
reset_duration);
}
static int ziirave_wdt_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret;
struct ziirave_wdt_data *w_priv;
int val;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
w_priv = devm_kzalloc(&client->dev, sizeof(*w_priv), GFP_KERNEL);
if (!w_priv)
return -ENOMEM;
mutex_init(&w_priv->sysfs_mutex);
w_priv->wdd.info = &ziirave_wdt_info;
w_priv->wdd.ops = &ziirave_wdt_ops;
w_priv->wdd.min_timeout = ZIIRAVE_TIMEOUT_MIN;
w_priv->wdd.max_timeout = ZIIRAVE_TIMEOUT_MAX;
w_priv->wdd.parent = &client->dev;
w_priv->wdd.groups = ziirave_wdt_groups;
watchdog_init_timeout(&w_priv->wdd, wdt_timeout, &client->dev);
/*
* The default value set in the watchdog should be perfectly valid, so
* pass that in if we haven't provided one via the module parameter or
* of property.
*/
if (w_priv->wdd.timeout == 0) {
val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_TIMEOUT);
if (val < 0)
return val;
if (val < ZIIRAVE_TIMEOUT_MIN)
return -ENODEV;
w_priv->wdd.timeout = val;
} else {
ret = ziirave_wdt_set_timeout(&w_priv->wdd,
w_priv->wdd.timeout);
if (ret)
return ret;
dev_info(&client->dev, "Timeout set to %ds.",
w_priv->wdd.timeout);
}
watchdog_set_nowayout(&w_priv->wdd, nowayout);
i2c_set_clientdata(client, w_priv);
/* If in unconfigured state, set to stopped */
val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_STATE);
if (val < 0)
return val;
if (val == ZIIRAVE_STATE_INITIAL)
ziirave_wdt_stop(&w_priv->wdd);
ret = ziirave_wdt_init_duration(client);
if (ret)
return ret;
ret = ziirave_wdt_revision(client, &w_priv->firmware_rev,
ZIIRAVE_WDT_FIRM_VER_MAJOR);
if (ret)
return ret;
ret = ziirave_wdt_revision(client, &w_priv->bootloader_rev,
ZIIRAVE_WDT_BOOT_VER_MAJOR);
if (ret)
return ret;
w_priv->reset_reason = i2c_smbus_read_byte_data(client,
ZIIRAVE_WDT_RESET_REASON);
if (w_priv->reset_reason < 0)
return w_priv->reset_reason;
if (w_priv->reset_reason >= ARRAY_SIZE(ziirave_reasons) ||
!ziirave_reasons[w_priv->reset_reason])
return -ENODEV;
ret = watchdog_register_device(&w_priv->wdd);
return ret;
}
static int ziirave_wdt_remove(struct i2c_client *client)
{
struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
watchdog_unregister_device(&w_priv->wdd);
return 0;
}
static const struct i2c_device_id ziirave_wdt_id[] = {
{ "rave-wdt", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ziirave_wdt_id);
static const struct of_device_id zrv_wdt_of_match[] = {
{ .compatible = "zii,rave-wdt", },
{ },
};
MODULE_DEVICE_TABLE(of, zrv_wdt_of_match);
static struct i2c_driver ziirave_wdt_driver = {
.driver = {
.name = "ziirave_wdt",
.of_match_table = zrv_wdt_of_match,
},
.probe = ziirave_wdt_probe,
.remove = ziirave_wdt_remove,
.id_table = ziirave_wdt_id,
};
module_i2c_driver(ziirave_wdt_driver);
MODULE_AUTHOR("Martyn Welch <martyn.welch@collabora.co.uk");
MODULE_DESCRIPTION("Zodiac Aerospace RAVE Switch Watchdog Processor Driver");
MODULE_LICENSE("GPL");