diff options
| -rw-r--r-- | Documentation/devicetree/bindings/watchdog/moxa,moxart-watchdog.txt | 15 | ||||
| -rw-r--r-- | drivers/watchdog/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/watchdog/Makefile | 1 | ||||
| -rw-r--r-- | drivers/watchdog/moxart_wdt.c | 165 |
4 files changed, 191 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/watchdog/moxa,moxart-watchdog.txt b/Documentation/devicetree/bindings/watchdog/moxa,moxart-watchdog.txt new file mode 100644 index 0000000..1169857 --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/moxa,moxart-watchdog.txt @@ -0,0 +1,15 @@ +MOXA ART Watchdog timer + +Required properties: + +- compatible : Must be "moxa,moxart-watchdog" +- reg : Should contain registers location and length +- clocks : Should contain phandle for the clock that drives the counter + +Example: + + watchdog: watchdog@98500000 { + compatible = "moxa,moxart-watchdog"; + reg = <0x98500000 0x10>; + clocks = <&coreclk>; + }; diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 6df632e..7fc6e10 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -392,6 +392,16 @@ 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 8c7b8bc..40c36cc 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -55,6 +55,7 @@ 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..4166e4d --- /dev/null +++ b/drivers/watchdog/moxart_wdt.c @@ -0,0 +1,165 @@ +/* + * MOXA ART SoCs watchdog driver. + * + * Copyright (C) 2013 Jonas Jensen + * + * Jonas Jensen <jonas.jensen@gmail.com> + * + * 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/io.h> +#include <linux/module.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/watchdog.h> +#include <linux/moduleparam.h> + +#define REG_COUNT 0x4 +#define REG_MODE 0x8 +#define REG_ENABLE 0xC + +struct moxart_wdt_dev { + struct watchdog_device dev; + void __iomem *base; + unsigned int clock_frequency; +}; + +static int heartbeat; + +static int moxart_wdt_stop(struct watchdog_device *wdt_dev) +{ + struct moxart_wdt_dev *moxart_wdt = watchdog_get_drvdata(wdt_dev); + + writel(0, moxart_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); + + writel(moxart_wdt->clock_frequency * wdt_dev->timeout, + moxart_wdt->base + REG_COUNT); + writel(0x5ab9, moxart_wdt->base + REG_MODE); + writel(0x03, moxart_wdt->base + REG_ENABLE); + + return 0; +} + +static int moxart_wdt_set_timeout(struct watchdog_device *wdt_dev, + unsigned int timeout) +{ + 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 moxart_wdt_dev *moxart_wdt; + struct device *dev = &pdev->dev; + struct device_node *node = dev->of_node; + struct resource *res; + struct clk *clk; + int err; + unsigned int max_timeout; + bool nowayout = WATCHDOG_NOWAYOUT; + + moxart_wdt = devm_kzalloc(dev, sizeof(*moxart_wdt), GFP_KERNEL); + if (!moxart_wdt) + return -ENOMEM; + + platform_set_drvdata(pdev, moxart_wdt); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + moxart_wdt->base = devm_ioremap_resource(dev, res); + if (IS_ERR(moxart_wdt->base)) + return PTR_ERR(moxart_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); + } + + moxart_wdt->clock_frequency = clk_get_rate(clk); + if (moxart_wdt->clock_frequency == 0) { + pr_err("%s: incorrect clock frequency\n", __func__); + return -EINVAL; + } + + max_timeout = UINT_MAX / moxart_wdt->clock_frequency; + + moxart_wdt->dev.info = &moxart_wdt_info; + moxart_wdt->dev.ops = &moxart_wdt_ops; + moxart_wdt->dev.timeout = max_timeout; + moxart_wdt->dev.min_timeout = 1; + moxart_wdt->dev.max_timeout = max_timeout; + moxart_wdt->dev.parent = dev; + + watchdog_init_timeout(&moxart_wdt->dev, heartbeat, dev); + watchdog_set_nowayout(&moxart_wdt->dev, nowayout); + + watchdog_set_drvdata(&moxart_wdt->dev, moxart_wdt); + + err = watchdog_register_device(&moxart_wdt->dev); + if (err) + return err; + + dev_dbg(dev, "Watchdog enabled (heartbeat=%d sec, nowayout=%d)\n", + moxart_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->dev); + watchdog_unregister_device(&moxart_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@gmail.com>"); |
