Signed-off-by: Tim Harvey <tharvey@xxxxxxxxxxxxx> --- drivers/watchdog/Kconfig | 10 ++++ drivers/watchdog/Makefile | 1 + drivers/watchdog/gsc_wdt.c | 146 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 157 insertions(+) create mode 100644 drivers/watchdog/gsc_wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index ca200d1..c9d4b2e 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -150,6 +150,16 @@ config GPIO_WATCHDOG_ARCH_INITCALL arch_initcall. If in doubt, say N. +config GSC_WATCHDOG + tristate "Gateworks System Controller (GSC) Watchdog support" + depends on MFD_GATEWORKS_GSC + select WATCHDOG_CORE + help + Say Y here to include support for the GSC Watchdog. + + This driver can also be built as a module. If so the module + will be called gsc_wdt. + config MENF21BMC_WATCHDOG tristate "MEN 14F021P00 BMC Watchdog" depends on MFD_MENF21BMC || COMPILE_TEST diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 715a210..499327e 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -215,6 +215,7 @@ obj-$(CONFIG_DA9055_WATCHDOG) += da9055_wdt.o obj-$(CONFIG_DA9062_WATCHDOG) += da9062_wdt.o obj-$(CONFIG_DA9063_WATCHDOG) += da9063_wdt.o obj-$(CONFIG_GPIO_WATCHDOG) += gpio_wdt.o +obj-$(CONFIG_GSC_WATCHDOG) += gsc_wdt.o obj-$(CONFIG_TANGOX_WATCHDOG) += tangox_wdt.o obj-$(CONFIG_WDAT_WDT) += wdat_wdt.o obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o diff --git a/drivers/watchdog/gsc_wdt.c b/drivers/watchdog/gsc_wdt.c new file mode 100644 index 0000000..b43d083 --- /dev/null +++ b/drivers/watchdog/gsc_wdt.c @@ -0,0 +1,146 @@ +/* SPDX-License-Identifier: GPL-2.0 + * + * Copyright (C) 2018 Gateworks Corporation + * + * This driver registers a Linux Watchdog for the GSC + */ +#include <linux/mfd/gsc.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/watchdog.h> + +#define WDT_DEFAULT_TIMEOUT 60 + +struct gsc_wdt { + struct watchdog_device wdt_dev; + struct gsc_dev *gsc; +}; + +static int gsc_wdt_start(struct watchdog_device *wdd) +{ + struct gsc_wdt *wdt = watchdog_get_drvdata(wdd); + unsigned int reg = (1 << GSC_CTRL_1_WDT_ENABLE); + int ret; + + dev_dbg(wdd->parent, "%s timeout=%d\n", __func__, wdd->timeout); + + /* clear first as regmap_update_bits will not write if no change */ + ret = regmap_update_bits(wdt->gsc->regmap, GSC_CTRL_1, reg, 0); + if (ret) + return ret; + return regmap_update_bits(wdt->gsc->regmap, GSC_CTRL_1, reg, reg); +} + +static int gsc_wdt_stop(struct watchdog_device *wdd) +{ + struct gsc_wdt *wdt = watchdog_get_drvdata(wdd); + unsigned int reg = (1 << GSC_CTRL_1_WDT_ENABLE); + + dev_dbg(wdd->parent, "%s\n", __func__); + + return regmap_update_bits(wdt->gsc->regmap, GSC_CTRL_1, reg, 0); +} + +static int gsc_wdt_set_timeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + struct gsc_wdt *wdt = watchdog_get_drvdata(wdd); + unsigned int long_sel = 0; + + dev_dbg(wdd->parent, "%s: %d\n", __func__, timeout); + + switch (timeout) { + case 60: + long_sel = (1 << GSC_CTRL_1_WDT_TIME); + case 30: + regmap_update_bits(wdt->gsc->regmap, GSC_CTRL_1, + (1 << GSC_CTRL_1_WDT_TIME), + (long_sel << GSC_CTRL_1_WDT_TIME)); + wdd->timeout = timeout; + return 0; + } + + return -EINVAL; +} + +static const struct watchdog_info gsc_wdt_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, + .identity = "GSC Watchdog" +}; + +static const struct watchdog_ops gsc_wdt_ops = { + .owner = THIS_MODULE, + .start = gsc_wdt_start, + .stop = gsc_wdt_stop, + .set_timeout = gsc_wdt_set_timeout, +}; + +static int gsc_wdt_probe(struct platform_device *pdev) +{ + struct gsc_dev *gsc = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + struct gsc_wdt *wdt; + int ret; + unsigned int reg; + + wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL); + if (!wdt) + return -ENOMEM; + + /* ensure GSC fw supports WD functionality */ + if (gsc->fwver < 44) { + dev_err(dev, "fw v44 or newer required for wdt function\n"); + return -EINVAL; + } + + /* ensure WD bit enabled */ + if (regmap_read(gsc->regmap, GSC_CTRL_1, ®)) + return -EIO; + if (!(reg & (1 << GSC_CTRL_1_WDT_ENABLE))) { + dev_err(dev, "not enabled - must be manually enabled\n"); + return -EINVAL; + } + + platform_set_drvdata(pdev, wdt); + + wdt->gsc = gsc; + wdt->wdt_dev.info = &gsc_wdt_info; + wdt->wdt_dev.ops = &gsc_wdt_ops; + wdt->wdt_dev.status = 0; + wdt->wdt_dev.min_timeout = 30; + wdt->wdt_dev.max_timeout = 60; + wdt->wdt_dev.parent = dev; + + watchdog_set_nowayout(&wdt->wdt_dev, 1); + watchdog_init_timeout(&wdt->wdt_dev, WDT_DEFAULT_TIMEOUT, dev); + + watchdog_set_drvdata(&wdt->wdt_dev, wdt); + ret = devm_watchdog_register_device(dev, &wdt->wdt_dev); + if (ret) + return ret; + + dev_info(dev, "watchdog driver (timeout=%d sec)\n", + wdt->wdt_dev.timeout); + + return 0; +} + +static const struct of_device_id gsc_wdt_dt_ids[] = { + { .compatible = "gw,gsc-watchdog", }, + {} +}; + +static struct platform_driver gsc_wdt_driver = { + .probe = gsc_wdt_probe, + .driver = { + .name = "gsc-wdt", + .of_match_table = gsc_wdt_dt_ids, + }, +}; + +module_platform_driver(gsc_wdt_driver); + +MODULE_AUTHOR("Tim Harvey <tharvey@xxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Gateworks System Controller Watchdog driver"); +MODULE_LICENSE("GPL v2"); -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html