diff options
Diffstat (limited to 'drivers/watchdog/twl4030_wdt.c')
| -rw-r--r-- | drivers/watchdog/twl4030_wdt.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/drivers/watchdog/twl4030_wdt.c b/drivers/watchdog/twl4030_wdt.c new file mode 100644 index 000000000..2c1db6fa9 --- /dev/null +++ b/drivers/watchdog/twl4030_wdt.c @@ -0,0 +1,153 @@ +/* + * Copyright (C) Nokia Corporation + * + * Written by Timo Kokkonen <timo.t.kokkonen at nokia.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. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/watchdog.h> +#include <linux/platform_device.h> +#include <linux/i2c/twl.h> + +#define TWL4030_WATCHDOG_CFG_REG_OFFS 0x3 + +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 twl4030_wdt_write(unsigned char val) +{ + return twl_i2c_write_u8(TWL_MODULE_PM_RECEIVER, val, + TWL4030_WATCHDOG_CFG_REG_OFFS); +} + +static int twl4030_wdt_start(struct watchdog_device *wdt) +{ + return twl4030_wdt_write(wdt->timeout + 1); +} + +static int twl4030_wdt_stop(struct watchdog_device *wdt) +{ + return twl4030_wdt_write(0); +} + +static int twl4030_wdt_set_timeout(struct watchdog_device *wdt, + unsigned int timeout) +{ + wdt->timeout = timeout; + return 0; +} + +static const struct watchdog_info twl4030_wdt_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, + .identity = "TWL4030 Watchdog", +}; + +static const struct watchdog_ops twl4030_wdt_ops = { + .owner = THIS_MODULE, + .start = twl4030_wdt_start, + .stop = twl4030_wdt_stop, + .set_timeout = twl4030_wdt_set_timeout, +}; + +static int twl4030_wdt_probe(struct platform_device *pdev) +{ + int ret = 0; + struct watchdog_device *wdt; + + wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL); + if (!wdt) + return -ENOMEM; + + wdt->info = &twl4030_wdt_info; + wdt->ops = &twl4030_wdt_ops; + wdt->status = 0; + wdt->timeout = 30; + wdt->min_timeout = 1; + wdt->max_timeout = 30; + + watchdog_set_nowayout(wdt, nowayout); + platform_set_drvdata(pdev, wdt); + + twl4030_wdt_stop(wdt); + + ret = watchdog_register_device(wdt); + if (ret) + return ret; + + return 0; +} + +static int twl4030_wdt_remove(struct platform_device *pdev) +{ + struct watchdog_device *wdt = platform_get_drvdata(pdev); + + watchdog_unregister_device(wdt); + + return 0; +} + +#ifdef CONFIG_PM +static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct watchdog_device *wdt = platform_get_drvdata(pdev); + if (watchdog_active(wdt)) + return twl4030_wdt_stop(wdt); + + return 0; +} + +static int twl4030_wdt_resume(struct platform_device *pdev) +{ + struct watchdog_device *wdt = platform_get_drvdata(pdev); + if (watchdog_active(wdt)) + return twl4030_wdt_start(wdt); + + return 0; +} +#else +#define twl4030_wdt_suspend NULL +#define twl4030_wdt_resume NULL +#endif + +static const struct of_device_id twl_wdt_of_match[] = { + { .compatible = "ti,twl4030-wdt", }, + { }, +}; +MODULE_DEVICE_TABLE(of, twl_wdt_of_match); + +static struct platform_driver twl4030_wdt_driver = { + .probe = twl4030_wdt_probe, + .remove = twl4030_wdt_remove, + .suspend = twl4030_wdt_suspend, + .resume = twl4030_wdt_resume, + .driver = { + .name = "twl4030_wdt", + .of_match_table = twl_wdt_of_match, + }, +}; + +module_platform_driver(twl4030_wdt_driver); + +MODULE_AUTHOR("Nokia Corporation"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:twl4030_wdt"); + |