Add a driver for the watchdog timer block found in the Krait Processor Subsystem (KPSS) on the MSM8960, APQ8064, and IPQ8064.
Signed-off-by: Josh Cartwright <jo...@codeaurora.org> --- drivers/watchdog/Kconfig | 10 +++ drivers/watchdog/Makefile | 1 + drivers/watchdog/qcom-wdt.c | 145 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 156 insertions(+) create mode 100644 drivers/watchdog/qcom-wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 1d1330a..5ccb963 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -443,6 +443,16 @@ config TEGRA_WATCHDOG To compile this driver as a module, choose M here: the module will be called tegra_wdt. +config QCOM_WDT + bool "QCOM watchdog" + depends on HAS_IOMEM + depends on ARCH_QCOM + select WATCHDOG_CORE + help + Say Y here to include Watchdog timer support for the watchdog found + on QCOM chipsets. Currently supported targets are the MSM8960, + APQ8064, and IPQ8064. + # AVR32 Architecture config AT32AP700X_WDT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 468c320..d645448 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -57,6 +57,7 @@ obj-$(CONFIG_RETU_WATCHDOG) += retu_wdt.o obj-$(CONFIG_BCM2835_WDT) += bcm2835_wdt.o obj-$(CONFIG_MOXART_WDT) += moxart_wdt.o obj-$(CONFIG_SIRFSOC_WATCHDOG) += sirfsoc_wdt.o +obj-$(CONFIG_QCOM_WDT) += qcom-wdt.o obj-$(CONFIG_BCM_KONA_WDT) += bcm_kona_wdt.o obj-$(CONFIG_TEGRA_WATCHDOG) += tegra_wdt.o diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c new file mode 100644 index 0000000..e9409f5 --- /dev/null +++ b/drivers/watchdog/qcom-wdt.c @@ -0,0 +1,145 @@ +/* Copyright (c) 2014, The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * 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. + * + */ +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/watchdog.h> + +#define WDT_RST 0x0 +#define WDT_EN 0x8 +#define WDT_BITE_TIME 0x24 + +struct qcom_wdt { + struct watchdog_device wdd; + unsigned long freq; + void __iomem *base; +}; + +static inline +struct qcom_wdt *to_qcom_wdt(struct watchdog_device *wdd) +{ + return container_of(wdd, struct qcom_wdt, wdd); +} + +static int qcom_wdt_start(struct watchdog_device *wdd) +{ + struct qcom_wdt *wdt = to_qcom_wdt(wdd); + + writel(0, wdt->base + WDT_EN); + writel(1, wdt->base + WDT_RST); + writel(wdd->timeout * wdt->freq, wdt->base + WDT_BITE_TIME); + writel(1, wdt->base + WDT_EN); + return 0; +} + +static int qcom_wdt_stop(struct watchdog_device *wdd) +{ + struct qcom_wdt *wdt = to_qcom_wdt(wdd); + + writel(0, wdt->base + WDT_EN); + return 0; +} + +static int qcom_wdt_ping(struct watchdog_device *wdd) +{ + struct qcom_wdt *wdt = to_qcom_wdt(wdd); + + writel(1, wdt->base + WDT_RST); + return 0; +} + +static int qcom_wdt_set_timeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + wdd->timeout = timeout; + return qcom_wdt_start(wdd); +} + +static const struct watchdog_ops qcom_wdt_ops = { + .start = qcom_wdt_start, + .stop = qcom_wdt_stop, + .ping = qcom_wdt_ping, + .set_timeout = qcom_wdt_set_timeout, + .owner = THIS_MODULE, +}; + +static const struct watchdog_info qcom_wdt_info = { + .options = WDIOF_KEEPALIVEPING + | WDIOF_MAGICCLOSE + | WDIOF_SETTIMEOUT, + .identity = KBUILD_MODNAME, +}; + +static int qcom_watchdog_probe(struct platform_device *pdev) +{ + struct qcom_wdt *wdt; + struct resource *res; + u32 tmp; + int ret; + + wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL); + if (!wdt) + return -ENOMEM; + + platform_set_drvdata(pdev, wdt); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + wdt->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(wdt->base)) + return PTR_ERR(wdt->base); + + ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency", &tmp); + if (ret) { + dev_err(&pdev->dev, "unable to get clock-frequency\n"); + return ret; + } + + wdt->freq = tmp; + + wdt->wdd.dev = &pdev->dev; + wdt->wdd.info = &qcom_wdt_info; + wdt->wdd.ops = &qcom_wdt_ops; + wdt->wdd.min_timeout = 1; + wdt->wdd.max_timeout = 0x10000000U / wdt->freq; + watchdog_init_timeout(&wdt->wdd, 0, &pdev->dev); + + ret = watchdog_register_device(&wdt->wdd); + if (ret) { + dev_err(&pdev->dev, "failed to register watchdog\n"); + return ret; + } + + return 0; +} + +static const struct of_device_id qcom_wdt_of_table[] = { + { .compatible = "qcom,kpss-wdt-msm8960", }, + { .compatible = "qcom,kpss-wdt-apq8064", }, + { .compatible = "qcom,kpss-wdt-ipq8064", }, + { }, +}; +MODULE_DEVICE_TABLE(of, qcom_wdt_of_table); + +static struct platform_driver qcom_watchdog_driver = { + .probe = qcom_watchdog_probe, + .driver = { + .name = KBUILD_MODNAME, + .of_match_table = qcom_wdt_of_table, + }, +}; +module_platform_driver(qcom_watchdog_driver); + +MODULE_DESCRIPTION("QCOM KPSS Watchdog Driver"); +MODULE_LICENSE("GPL v2"); -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/