On Thu, May 06, 2021 at 04:16:18PM +0800, Campion Kang wrote: > 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 GPL or GPLv2 ? > +/* > + * 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> Unnecessary. > +#include <linux/platform_data/ahc1ec0.h> > +#include <linux/platform_device.h> > +#include <linux/reboot.h> Unnecessary. > +#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 */ This variable is unnecessary. > +}; > + > +#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) */ Please use constant alignment, and "The watchdog devices " is really unnecessary. > +#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)) Those functions presumably return a valid error code which should be passed on and not replaced. > + 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; > + Might as well be written as struct adv_ec_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; timeout_in_ds can be a local variable (if not omitted entirely). > + > + ret = set_delay(ddata, (ec_wdt_data->timeout_in_ds - 1)); Unnecessary ( ) around second parameter. > + if (ret) > + goto exit; if (ret) return ret; > + > + ahc1ec_write_hwram_command(ddata, EC_WDT_STOP); > + ret = ahc1ec_write_hwram_command(ddata, EC_WDT_START); > + if (ret) > + goto exit; Unnecessary. > + > +exit: Unnecessary label. > + 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 ret; but then above you have return ahc1ec_write_hwram_command(ddata, EC_WDT_STOP); Please be consistent. > + > + 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); > + This should be after wdd->timeout is set, and please use wdd. > + /* watchdog_set_nowayout(&ec_wdt_data->wdtdev, WATCHDOG_NOWAYOUT); */ > + watchdog_set_drvdata(&ec_wdt_data->wdtdev, ec_wdt_data); Please use wdd. > + platform_set_drvdata(pdev, ec_wdt_data); Is this used anywhere ? > + > + 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; wdd->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"); This is noise. > + > + 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 >
