A good watchdog driver is supposed to report when it was responsible for resetting the system. Implement this for the s3c2410, at least on exynos5250 and exynos5420 where we already have a pointer to the PMU registers to read the information.
Signed-off-by: Doug Anderson <diand...@chromium.org> --- This patch is based atop Leela Krishna's recent series that ends with (ARM: dts: update watchdog device nodes for Exynos5250 and Exynos5420) AKA <https://patchwork.kernel.org/patch/3251861/>. drivers/watchdog/s3c2410_wdt.c | 42 +++++++++++++++++++++++++++++++++++++++--- 1 file changed, 39 insertions(+), 3 deletions(-) diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c index 47f4dcf..2c87d37 100644 --- a/drivers/watchdog/s3c2410_wdt.c +++ b/drivers/watchdog/s3c2410_wdt.c @@ -62,9 +62,13 @@ #define CONFIG_S3C2410_WATCHDOG_ATBOOT (0) #define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME (15) +#define RST_STAT_REG_OFFSET 0x0404 #define WDT_DISABLE_REG_OFFSET 0x0408 #define WDT_MASK_RESET_REG_OFFSET 0x040c #define QUIRK_NEEDS_PMU_CONFIG (1 << 0) +#define QUIRK_HAS_RST_STAT (1 << 1) +#define QUIRKS_NEED_PMUREG (QUIRK_NEEDS_PMU_CONFIG | \ + QUIRK_HAS_RST_STAT) static bool nowayout = WATCHDOG_NOWAYOUT; static int tmr_margin; @@ -98,6 +102,9 @@ MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug (default 0)"); * timer reset functionality. * @mask_bit: Bit number for the watchdog timer in the disable register and the * mask reset register. + * @rst_stat_reg: Offset in pmureg for the register that has the reset status. + * @rst_stat_bit: Bit number in the rst_stat register indicating a watchdog + * reset. * @quirks: A bitfield of quirks. */ @@ -105,6 +112,8 @@ struct s3c2410_wdt_variant { int disable_reg; int mask_reset_reg; int mask_bit; + int rst_stat_reg; + int rst_stat_bit; u32 quirks; }; @@ -131,14 +140,20 @@ static const struct s3c2410_wdt_variant drv_data_exynos5250 = { .disable_reg = WDT_DISABLE_REG_OFFSET, .mask_reset_reg = WDT_MASK_RESET_REG_OFFSET, .mask_bit = 20, - .quirks = QUIRK_NEEDS_PMU_CONFIG + .rst_stat_reg = RST_STAT_REG_OFFSET, + .rst_stat_bit = 20, + .quirks = QUIRK_NEEDS_PMU_CONFIG | + QUIRK_HAS_RST_STAT, }; static const struct s3c2410_wdt_variant drv_data_exynos5420 = { .disable_reg = WDT_DISABLE_REG_OFFSET, .mask_reset_reg = WDT_MASK_RESET_REG_OFFSET, .mask_bit = 0, - .quirks = QUIRK_NEEDS_PMU_CONFIG + .rst_stat_reg = RST_STAT_REG_OFFSET, + .rst_stat_bit = 9, + .quirks = QUIRK_NEEDS_PMU_CONFIG | + QUIRK_HAS_RST_STAT, }; static const struct of_device_id s3c2410_wdt_match[] = { @@ -423,6 +438,25 @@ static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt) } #endif +static inline unsigned int s3c2410wdt_get_bootstatus(struct s3c2410_wdt *wdt) +{ + unsigned int bootstatus = 0; + int ret; + + if (wdt->drv_data->quirks & QUIRK_HAS_RST_STAT) { + unsigned int rst_stat; + + ret = regmap_read(wdt->pmureg, wdt->drv_data->rst_stat_reg, + &rst_stat); + if (ret) + dev_warn(wdt->dev, "Couldn't get RST_STAT register\n"); + else if (rst_stat & BIT(wdt->drv_data->rst_stat_bit)) + bootstatus |= WDIOF_CARDRESET; + } + + return bootstatus; +} + /* s3c2410_get_wdt_driver_data */ static inline struct s3c2410_wdt_variant * get_wdt_drv_data(struct platform_device *pdev) @@ -460,7 +494,7 @@ static int s3c2410wdt_probe(struct platform_device *pdev) wdt->wdt_device = s3c2410_wdd; wdt->drv_data = get_wdt_drv_data(pdev); - if (wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG) { + if (wdt->drv_data->quirks & QUIRKS_NEED_PMUREG) { wdt->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node, "samsung,syscon-phandle"); if (IS_ERR(wdt->pmureg)) { @@ -531,6 +565,8 @@ static int s3c2410wdt_probe(struct platform_device *pdev) watchdog_set_nowayout(&wdt->wdt_device, nowayout); + wdt->wdt_device.bootstatus = s3c2410wdt_get_bootstatus(wdt); + ret = watchdog_register_device(&wdt->wdt_device); if (ret) { dev_err(dev, "cannot register watchdog (%d)\n", ret); -- 1.8.4.1 -- 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/
