This is one of sub-device driver for Advantech embedded controller AHC1EC0. This driver provide Watchdog functionality for Advantech related applications to restart the system. Changed in V7: Fix the patch according to reviewer's comment: - remove unnecessary variables and fix error checks - remove error messages that avoid clogging the kernel log - remove advwdt_notify_sys(), use watchdog subsystem to process reboot or shutdown - delete mutex lock, the watchdog core has processed it Changed in V6: - remove unnecessary header files - bug fixed: reboot halt if watchdog enabled - Kconfig: add "AHC1EC0" string to clearly define the EC name Signed-off-by: Campion Kang <campion.kang@xxxxxxxxxxxxxxxx> --- drivers/watchdog/Kconfig | 11 +++ drivers/watchdog/Makefile | 1 + drivers/watchdog/ahc1ec0-wdt.c | 171 +++++++++++++++++++++++++++++++++ 3 files changed, 183 insertions(+) create mode 100644 drivers/watchdog/ahc1ec0-wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 355100dad60a..5fe9add0a12d 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -1005,6 +1005,17 @@ config ADVANTECH_WDT feature. More information can be found at <https://www.advantech.com.tw/products/> +config AHC1EC0_WDT + tristate "Advantech AHC1EC0 Watchdog Function" + depends on MFD_AHC1EC0 + help + This is sub-device for Advantech AHC1EC0 embedded controller. + + This driver provide watchdog functionality for Advantech related + applications to restart the system. + To compile this driver as a module, choose M here: the module will be + called ahc1ec0-wdt. + config ALIM1535_WDT tristate "ALi M1535 PMU Watchdog Timer" depends on X86 && PCI diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index a7eade8b4d45..0d78211e1412 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -142,6 +142,7 @@ obj-$(CONFIG_NI903X_WDT) += ni903x_wdt.o obj-$(CONFIG_NIC7018_WDT) += nic7018_wdt.o obj-$(CONFIG_MLX_WDT) += mlx_wdt.o obj-$(CONFIG_KEEMBAY_WATCHDOG) += keembay_wdt.o +obj-$(CONFIG_AHC1EC0_WDT) += ahc1ec0-wdt.o # M68K Architecture obj-$(CONFIG_M54xx_WATCHDOG) += m54xx_wdt.o diff --git a/drivers/watchdog/ahc1ec0-wdt.c b/drivers/watchdog/ahc1ec0-wdt.c new file mode 100644 index 000000000000..efa955c41a81 --- /dev/null +++ b/drivers/watchdog/ahc1ec0-wdt.c @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Watchdog Driver for Advantech AHC1EC0 Embedded Controller + * + * Copyright 2021, Advantech IIoT Group + */ + +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/notifier.h> +#include <linux/platform_data/ahc1ec0.h> +#include <linux/platform_device.h> +#include <linux/reboot.h> +#include <linux/types.h> +#include <linux/watchdog.h> + +struct ec_wdt_data { + struct watchdog_device wdtdev; + struct adv_ec_ddata *ddata; + unsigned short timeout_in_ds; /* a decisecond */ +}; + +#define EC_WDT_MIN_TIMEOUT 1 /* The watchdog devices minimum timeout value (in seconds). */ +#define EC_WDT_MAX_TIMEOUT 600 /* The watchdog devices maximum timeout value (in seconds) */ +#define EC_WDT_DEFAULT_TIMEOUT 45 + +static int set_delay(struct adv_ec_ddata *ddata, unsigned short delay_timeout_in_ms) +{ + if (ahc1ec_write_hw_ram(ddata, EC_RESET_DELAY_TIME_L, + delay_timeout_in_ms & 0x00FF)) + return -EINVAL; + + if (ahc1ec_write_hw_ram(ddata, EC_RESET_DELAY_TIME_H, + (delay_timeout_in_ms & 0xFF00) >> 8)) + return -EINVAL; + + return 0; +} + +static int ec_wdt_start(struct watchdog_device *wdd) +{ + int ret; + struct ec_wdt_data *ec_wdt_data = watchdog_get_drvdata(wdd); + struct adv_ec_ddata *ddata; + + ddata = ec_wdt_data->ddata; + + /* + * Because an unit of ahc1ec0_wdt is 0.1 seconds, timeout 100 is 10 seconds + */ + ec_wdt_data->timeout_in_ds = wdd->timeout * 10; + + ret = set_delay(ddata, (ec_wdt_data->timeout_in_ds - 1)); + if (ret) + goto exit; + + ahc1ec_write_hwram_command(ddata, EC_WDT_STOP); + ret = ahc1ec_write_hwram_command(ddata, EC_WDT_START); + if (ret) + goto exit; + +exit: + return ret; +} + +static int ec_wdt_stop(struct watchdog_device *wdd) +{ + struct ec_wdt_data *ec_wdt_data = watchdog_get_drvdata(wdd); + struct adv_ec_ddata *ddata; + + ddata = ec_wdt_data->ddata; + + return ahc1ec_write_hwram_command(ddata, EC_WDT_STOP); +} + +static int ec_wdt_ping(struct watchdog_device *wdd) +{ + int ret; + struct ec_wdt_data *ec_wdt_data = watchdog_get_drvdata(wdd); + struct adv_ec_ddata *ddata; + + ddata = ec_wdt_data->ddata; + + ret = ahc1ec_write_hwram_command(ddata, EC_WDT_RESET); + if (ret) + return -EINVAL; + + return 0; +} + +static int ec_wdt_set_timeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + wdd->timeout = timeout; + + if (watchdog_active(wdd)) + return ec_wdt_start(wdd); + + return 0; +} + +static const struct watchdog_info ec_watchdog_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, + .identity = "AHC1EC0 Watchdog", +}; + +static const struct watchdog_ops ec_watchdog_ops = { + .owner = THIS_MODULE, + .start = ec_wdt_start, + .stop = ec_wdt_stop, + .ping = ec_wdt_ping, + .set_timeout = ec_wdt_set_timeout, +}; + +static int adv_ec_wdt_probe(struct platform_device *pdev) +{ + int ret; + struct device *dev = &pdev->dev; + struct adv_ec_ddata *ddata; + struct ec_wdt_data *ec_wdt_data; + struct watchdog_device *wdd; + + ddata = dev_get_drvdata(dev->parent); + if (!ddata) + return -EINVAL; + + ec_wdt_data = devm_kzalloc(dev, sizeof(*ec_wdt_data), GFP_KERNEL); + if (!ec_wdt_data) + return -ENOMEM; + + ec_wdt_data->ddata = ddata; + wdd = &ec_wdt_data->wdtdev; + + watchdog_init_timeout(&ec_wdt_data->wdtdev, 0, dev); + + /* watchdog_set_nowayout(&ec_wdt_data->wdtdev, WATCHDOG_NOWAYOUT); */ + watchdog_set_drvdata(&ec_wdt_data->wdtdev, ec_wdt_data); + platform_set_drvdata(pdev, ec_wdt_data); + + wdd->info = &ec_watchdog_info; + wdd->ops = &ec_watchdog_ops; + wdd->min_timeout = EC_WDT_MIN_TIMEOUT; + wdd->max_timeout = EC_WDT_MAX_TIMEOUT; + wdd->parent = dev; + + ec_wdt_data->wdtdev.timeout = EC_WDT_DEFAULT_TIMEOUT; + + watchdog_stop_on_reboot(wdd); + watchdog_stop_on_unregister(wdd); + + ret = devm_watchdog_register_device(dev, wdd); + if (ret == 0) + dev_info(dev, "ahc1ec0 watchdog register success\n"); + + return ret; +} + +static struct platform_driver adv_wdt_drv = { + .driver = { + .name = "ahc1ec0-wdt", + }, + .probe = adv_ec_wdt_probe, +}; +module_platform_driver(adv_wdt_drv); + +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ahc1ec0-wdt"); +MODULE_DESCRIPTION("Advantech Embedded Controller Watchdog Driver."); +MODULE_AUTHOR("Campion Kang <campion.kang@xxxxxxxxxxxxxxxx>"); +MODULE_VERSION("1.0"); -- 2.17.1
