mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 16:29:59 +00:00
![David Cohen](/assets/img/avatar_default.png)
Add initial Intel MID watchdog driver support. This driver is an initial implementation of generic Intel MID watchdog driver. Currently it supports Intel Merrifield platform. Signed-off-by: Eric Ernst <eric.ernst@intel.com> Signed-off-by: David Cohen <david.a.cohen@linux.intel.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
184 lines
4.2 KiB
C
184 lines
4.2 KiB
C
/*
|
|
* intel-mid_wdt: generic Intel MID SCU watchdog driver
|
|
*
|
|
* Platforms supported so far:
|
|
* - Merrifield only
|
|
*
|
|
* Copyright (C) 2014 Intel Corporation. All rights reserved.
|
|
* Contact: David Cohen <david.a.cohen@linux.intel.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of version 2 of the GNU General
|
|
* Public License as published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/interrupt.h>
|
|
#include <linux/module.h>
|
|
#include <linux/nmi.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/watchdog.h>
|
|
#include <linux/platform_data/intel-mid_wdt.h>
|
|
|
|
#include <asm/intel_scu_ipc.h>
|
|
#include <asm/intel-mid.h>
|
|
|
|
#define IPC_WATCHDOG 0xf8
|
|
|
|
#define MID_WDT_PRETIMEOUT 15
|
|
#define MID_WDT_TIMEOUT_MIN (1 + MID_WDT_PRETIMEOUT)
|
|
#define MID_WDT_TIMEOUT_MAX 170
|
|
#define MID_WDT_DEFAULT_TIMEOUT 90
|
|
|
|
/* SCU watchdog messages */
|
|
enum {
|
|
SCU_WATCHDOG_START = 0,
|
|
SCU_WATCHDOG_STOP,
|
|
SCU_WATCHDOG_KEEPALIVE,
|
|
};
|
|
|
|
static inline int wdt_command(int sub, u32 *in, int inlen)
|
|
{
|
|
return intel_scu_ipc_command(IPC_WATCHDOG, sub, in, inlen, NULL, 0);
|
|
}
|
|
|
|
static int wdt_start(struct watchdog_device *wd)
|
|
{
|
|
int ret, in_size;
|
|
int timeout = wd->timeout;
|
|
struct ipc_wd_start {
|
|
u32 pretimeout;
|
|
u32 timeout;
|
|
} ipc_wd_start = { timeout - MID_WDT_PRETIMEOUT, timeout };
|
|
|
|
/*
|
|
* SCU expects the input size for watchdog IPC to
|
|
* be based on 4 bytes
|
|
*/
|
|
in_size = DIV_ROUND_UP(sizeof(ipc_wd_start), 4);
|
|
|
|
ret = wdt_command(SCU_WATCHDOG_START, (u32 *)&ipc_wd_start, in_size);
|
|
if (ret) {
|
|
struct device *dev = watchdog_get_drvdata(wd);
|
|
dev_crit(dev, "error starting watchdog: %d\n", ret);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int wdt_ping(struct watchdog_device *wd)
|
|
{
|
|
int ret;
|
|
|
|
ret = wdt_command(SCU_WATCHDOG_KEEPALIVE, NULL, 0);
|
|
if (ret) {
|
|
struct device *dev = watchdog_get_drvdata(wd);
|
|
dev_crit(dev, "Error executing keepalive: 0x%x\n", ret);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int wdt_stop(struct watchdog_device *wd)
|
|
{
|
|
int ret;
|
|
|
|
ret = wdt_command(SCU_WATCHDOG_STOP, NULL, 0);
|
|
if (ret) {
|
|
struct device *dev = watchdog_get_drvdata(wd);
|
|
dev_crit(dev, "Error stopping watchdog: 0x%x\n", ret);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static irqreturn_t mid_wdt_irq(int irq, void *dev_id)
|
|
{
|
|
panic("Kernel Watchdog");
|
|
|
|
/* This code should not be reached */
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static const struct watchdog_info mid_wdt_info = {
|
|
.identity = "Intel MID SCU watchdog",
|
|
.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT,
|
|
};
|
|
|
|
static const struct watchdog_ops mid_wdt_ops = {
|
|
.owner = THIS_MODULE,
|
|
.start = wdt_start,
|
|
.stop = wdt_stop,
|
|
.ping = wdt_ping,
|
|
};
|
|
|
|
static int mid_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
struct watchdog_device *wdt_dev;
|
|
struct intel_mid_wdt_pdata *pdata = pdev->dev.platform_data;
|
|
int ret;
|
|
|
|
if (!pdata) {
|
|
dev_err(&pdev->dev, "missing platform data\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (pdata->probe) {
|
|
ret = pdata->probe(pdev);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
wdt_dev = devm_kzalloc(&pdev->dev, sizeof(*wdt_dev), GFP_KERNEL);
|
|
if (!wdt_dev)
|
|
return -ENOMEM;
|
|
|
|
wdt_dev->info = &mid_wdt_info;
|
|
wdt_dev->ops = &mid_wdt_ops;
|
|
wdt_dev->min_timeout = MID_WDT_TIMEOUT_MIN;
|
|
wdt_dev->max_timeout = MID_WDT_TIMEOUT_MAX;
|
|
wdt_dev->timeout = MID_WDT_DEFAULT_TIMEOUT;
|
|
|
|
watchdog_set_drvdata(wdt_dev, &pdev->dev);
|
|
platform_set_drvdata(pdev, wdt_dev);
|
|
|
|
ret = devm_request_irq(&pdev->dev, pdata->irq, mid_wdt_irq,
|
|
IRQF_SHARED | IRQF_NO_SUSPEND, "watchdog",
|
|
wdt_dev);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "error requesting warning irq %d\n",
|
|
pdata->irq);
|
|
return ret;
|
|
}
|
|
|
|
ret = watchdog_register_device(wdt_dev);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "error registering watchdog device\n");
|
|
return ret;
|
|
}
|
|
|
|
dev_info(&pdev->dev, "Intel MID watchdog device probed\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mid_wdt_remove(struct platform_device *pdev)
|
|
{
|
|
struct watchdog_device *wd = platform_get_drvdata(pdev);
|
|
watchdog_unregister_device(wd);
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver mid_wdt_driver = {
|
|
.probe = mid_wdt_probe,
|
|
.remove = mid_wdt_remove,
|
|
.driver = {
|
|
.owner = THIS_MODULE,
|
|
.name = "intel_mid_wdt",
|
|
},
|
|
};
|
|
|
|
module_platform_driver(mid_wdt_driver);
|
|
|
|
MODULE_AUTHOR("David Cohen <david.a.cohen@linux.intel.com>");
|
|
MODULE_DESCRIPTION("Watchdog Driver for Intel MID platform");
|
|
MODULE_LICENSE("GPL");
|