Add watchdog driver for MOXA ART SoCs. Signed-off-by: Jonas Jensen <jonas.jensen@xxxxxxxxx> --- Notes: Thanks for the review Guenter. Changes since v1: 1. remove moxart_wdt_ping 2. remove unnecessary max timeout check in moxart_wdt_set_timeout 3. remove arm_pm_restart and moxart_wdt_restart function (moved to moxart platform startup code) 4. remove unnecessary watchdog_set_drvdata from moxart_wdt_remove 5. stop the watchdog on driver remove Applies to next-20130716 drivers/watchdog/Kconfig | 10 +++ drivers/watchdog/Makefile | 1 + drivers/watchdog/moxart_wdt.c | 171 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 182 insertions(+) create mode 100644 drivers/watchdog/moxart_wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 362085d..6883aab 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -382,6 +382,16 @@ config RETU_WATCHDOG To compile this driver as a module, choose M here: the module will be called retu_wdt. +config MOXART_WDT + tristate "MOXART watchdog" + depends on ARCH_MOXART + help + Say Y here to include Watchdog timer support for the watchdog + existing on the MOXA ART SoC series platforms. + + To compile this driver as a module, choose M here: the + module will be called moxart_wdt. + # AVR32 Architecture config AT32AP700X_WDT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 2f26a0b..7cab53a 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -54,6 +54,7 @@ obj-$(CONFIG_IMX2_WDT) += imx2_wdt.o obj-$(CONFIG_UX500_WATCHDOG) += ux500_wdt.o obj-$(CONFIG_RETU_WATCHDOG) += retu_wdt.o obj-$(CONFIG_BCM2835_WDT) += bcm2835_wdt.o +obj-$(CONFIG_MOXART_WDT) += moxart_wdt.o # AVR32 Architecture obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o diff --git a/drivers/watchdog/moxart_wdt.c b/drivers/watchdog/moxart_wdt.c new file mode 100644 index 0000000..966855d --- /dev/null +++ b/drivers/watchdog/moxart_wdt.c @@ -0,0 +1,171 @@ +/* + * MOXA ART SoCs watchdog driver. + * + * Copyright (C) 2013 Jonas Jensen + * + * Jonas Jensen <jonas.jensen@xxxxxxxxx> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/types.h> +#include <linux/watchdog.h> + +#include <asm/system_misc.h> + +#define REG_COUNT 0x4 +#define REG_MODE 0x8 +#define REG_ENABLE 0xC + +struct moxart_wdt_dev { + struct watchdog_device wdt_dev; + void __iomem *wdt_base; +}; + +static struct moxart_wdt_dev *moxart_wdt; +static bool nowayout = WATCHDOG_NOWAYOUT; +static int heartbeat; +static unsigned int clock_frequency; +static unsigned int max_timeout; + +static int moxart_wdt_stop(struct watchdog_device *wdt_dev) +{ + struct moxart_wdt_dev *moxart_wdt = watchdog_get_drvdata(wdt_dev); + void __iomem *wdt_base = moxart_wdt->wdt_base; + + writel(0, wdt_base + REG_ENABLE); + + return 0; +} + +static int moxart_wdt_start(struct watchdog_device *wdt_dev) +{ + struct moxart_wdt_dev *moxart_wdt = watchdog_get_drvdata(wdt_dev); + void __iomem *wdt_base = moxart_wdt->wdt_base; + + writel(clock_frequency * moxart_wdt->wdt_dev.timeout, + wdt_base + REG_COUNT); + writel(0x5ab9, wdt_base + REG_MODE); + writel(0x03, wdt_base + REG_ENABLE); + + return 0; +} + +static int moxart_wdt_set_timeout(struct watchdog_device *wdt_dev, + unsigned int timeout) +{ + dev_dbg(wdt_dev->dev, "%s: timeout=%u\n", __func__, timeout); + + moxart_wdt->wdt_dev.timeout = timeout; + + return 0; +} + +static const struct watchdog_info moxart_wdt_info = { + .identity = "moxart-wdt", + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE, +}; + +static const struct watchdog_ops moxart_wdt_ops = { + .owner = THIS_MODULE, + .start = moxart_wdt_start, + .stop = moxart_wdt_stop, + .set_timeout = moxart_wdt_set_timeout, +}; + +static int moxart_wdt_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *node = dev->of_node; + struct resource *res; + struct clk *clk; + int err; + + moxart_wdt = devm_kzalloc(&pdev->dev, sizeof(*moxart_wdt), GFP_KERNEL); + if (!moxart_wdt) + return -EINVAL; + + platform_set_drvdata(pdev, moxart_wdt); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + moxart_wdt->wdt_base = devm_ioremap_resource(dev, res); + if (IS_ERR(moxart_wdt->wdt_base)) + return PTR_ERR(moxart_wdt->wdt_base); + + clk = of_clk_get(node, 0); + if (IS_ERR(clk)) { + pr_err("%s: of_clk_get failed\n", __func__); + return PTR_ERR(clk); + } + + clock_frequency = clk_get_rate(clk); + + max_timeout = UINT_MAX / clock_frequency; + + moxart_wdt->wdt_dev.info = &moxart_wdt_info; + moxart_wdt->wdt_dev.ops = &moxart_wdt_ops; + moxart_wdt->wdt_dev.timeout = max_timeout; + moxart_wdt->wdt_dev.min_timeout = 1; + moxart_wdt->wdt_dev.max_timeout = max_timeout; + moxart_wdt->wdt_dev.parent = &pdev->dev; + + watchdog_init_timeout(&moxart_wdt->wdt_dev, heartbeat, &pdev->dev); + watchdog_set_nowayout(&moxart_wdt->wdt_dev, nowayout); + + watchdog_set_drvdata(&moxart_wdt->wdt_dev, moxart_wdt); + + err = watchdog_register_device(&moxart_wdt->wdt_dev); + if (unlikely(err)) + return err; + + dev_dbg(dev, "Watchdog enabled (heartbeat=%d sec, nowayout=%d)\n", + moxart_wdt->wdt_dev.timeout, nowayout); + + return 0; +} + +static int moxart_wdt_remove(struct platform_device *pdev) +{ + struct moxart_wdt_dev *moxart_wdt = platform_get_drvdata(pdev); + + moxart_wdt_stop(&moxart_wdt->wdt_dev); + watchdog_unregister_device(&moxart_wdt->wdt_dev); + + return 0; +} + +static const struct of_device_id moxart_watchdog_match[] = { + { .compatible = "moxa,moxart-watchdog" }, + { }, +}; + +static struct platform_driver moxart_wdt_driver = { + .probe = moxart_wdt_probe, + .remove = moxart_wdt_remove, + .driver = { + .name = "moxart-watchdog", + .owner = THIS_MODULE, + .of_match_table = moxart_watchdog_match, + }, +}; +module_platform_driver(moxart_wdt_driver); + +module_param(heartbeat, int, 0); +MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds"); + +MODULE_DESCRIPTION("MOXART watchdog driver"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jonas Jensen <jonas.jensen@xxxxxxxxx>"); -- 1.8.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html