From: Graeme Gregory <gg@xxxxxxxxxxxxxxx> Add support for the Palmas watchdog timer which has a timeout configurable from 1s to 128s. Signed-off-by: Graeme Gregory <gg@xxxxxxxxxxxxxxx> Signed-off-by: Ian Lartey <ian@xxxxxxxxxxxxxxx> --- drivers/watchdog/palmas_wdt.c | 169 +++++++++++++++++++++++++++++++++++++++++ 1 files changed, 169 insertions(+), 0 deletions(-) create mode 100644 drivers/watchdog/palmas_wdt.c diff --git a/drivers/watchdog/palmas_wdt.c b/drivers/watchdog/palmas_wdt.c new file mode 100644 index 0000000..da7e379 --- /dev/null +++ b/drivers/watchdog/palmas_wdt.c @@ -0,0 +1,169 @@ +/* + * Driver for Watchdog part of Palmas PMIC Chips + * + * Copyright 2011-2013 Texas Instruments Inc. + * + * Author: Graeme Gregory <gg@xxxxxxxxxxxxxxx> + * Author: Ian Lartey <ian@xxxxxxxxxxxxxxx> + * + * Based on twl4030_wdt.c + * + * Author: 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. + * + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/watchdog.h> +#include <linux/platform_device.h> +#include <linux/watchdog.h> +#include <linux/mfd/palmas.h> + +struct palmas_wdt { + struct palmas *palmas; + struct watchdog_device wdt; + struct device *dev; + + int timer_margin; +}; + + +static int nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, int, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " + "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +static int palmas_wdt_write(struct palmas *palmas, unsigned int data) +{ + unsigned int addr; + + addr = PALMAS_BASE_TO_REG(PALMAS_PMU_CONTROL_BASE, PALMAS_WATCHDOG); + + return palmas_write(palmas, PALMAS_PMU_CONTROL_BASE, addr, addr); +} + +static int palmas_wdt_enable(struct watchdog_device *wdt) +{ + struct palmas_wdt *driver_data = watchdog_get_drvdata(wdt); + struct palmas *palmas = driver_data->palmas; + + return palmas_wdt_write(palmas, driver_data->timer_margin | + PALMAS_WATCHDOG_ENABLE); +} + +static int palmas_wdt_disable(struct watchdog_device *wdt) +{ + struct palmas_wdt *driver_data = watchdog_get_drvdata(wdt); + struct palmas *palmas = driver_data->palmas; + + return palmas_wdt_write(palmas, driver_data->timer_margin); +} + +static int palmas_wdt_set_timeout(struct watchdog_device *wdt, unsigned timeout) +{ + struct palmas_wdt *driver_data = watchdog_get_drvdata(wdt); + + if (timeout < 1 || timeout > 128) { + dev_warn(driver_data->dev, + "Timeout can only be in the range [1-128] seconds"); + return -EINVAL; + } + driver_data->timer_margin = fls(timeout) - 1; + return 0; +} + +static const struct watchdog_info palmas_wdt_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, + .identity = "Palmas Watchdog", + .firmware_version = 0, +}; + +static const struct watchdog_ops palmas_wdt_ops = { + .owner = THIS_MODULE, + .start = palmas_wdt_enable, + .stop = palmas_wdt_disable, + .ping = palmas_wdt_enable, + .set_timeout = palmas_wdt_set_timeout, +}; + +static int palmas_wdt_probe(struct platform_device *pdev) +{ + struct palmas *palmas = dev_get_drvdata(pdev->dev.parent); + struct palmas_wdt *driver_data; + struct watchdog_device *palmas_wdt; + int ret = 0; + + driver_data = devm_kzalloc(&pdev->dev, sizeof(*driver_data), + GFP_KERNEL); + if (!driver_data) { + dev_err(&pdev->dev, "Unable to alloacate watchdog device\n"); + ret = -ENOMEM; + goto err; + } + + driver_data->palmas = palmas; + + palmas_wdt = &driver_data->wdt; + + palmas_wdt->info = &palmas_wdt_info; + palmas_wdt->ops = &palmas_wdt_ops; + watchdog_set_nowayout(palmas_wdt, nowayout); + watchdog_set_drvdata(palmas_wdt, driver_data); + + ret = watchdog_register_device(&driver_data->wdt); + if (ret) { + platform_set_drvdata(pdev, NULL); + goto err; + } + + dev_set_drvdata(&pdev->dev, driver_data); + + return 0; +err: + return ret; +} + +static int palmas_wdt_remove(struct platform_device *pdev) +{ + struct palmas_wdt *driver_data = dev_get_drvdata(&pdev->dev); + + watchdog_unregister_device(&driver_data->wdt); + + return 0; +} + +static struct of_device_id of_palmas_match_tbl[] = { + { .compatible = "ti,palmas-wdt", }, + { .compatible = "ti,twl6035-wdt", }, + { .compatible = "ti,twl6036-wdt", }, + { .compatible = "ti,twl6037-wdt", }, + { .compatible = "ti,tps65913-wdt", }, + { .compatible = "ti,tps65914-wdt", }, + { .compatible = "ti,tps80036-wdt", }, + { /* end */ } +}; + +static struct platform_driver palmas_wdt_driver = { + .probe = palmas_wdt_probe, + .remove = palmas_wdt_remove, + .driver = { + .owner = THIS_MODULE, + .of_match_table = of_palmas_match_tbl, + .name = "palmas-wdt", + }, +}; + +module_platform_driver(palmas_wdt_driver); + +MODULE_AUTHOR("Graeme Gregory <gg@xxxxxxxxxxxxxxx>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:palmas-wdt"); +MODULE_DEVICE_TABLE(of, of_palmas_match_tbl); -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html