From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: Re: [PATCH V10 2/3] watchdog: s3c2410_wdt: use syscon regmap interface to configure pmu register Date: Wed, 27 Nov 2013 08:58:11 -0800 Message-ID: <529624A3.2030802@roeck-us.net> References: <1385553010-30183-1-git-send-email-l.krishna@samsung.com> <1385553010-30183-3-git-send-email-l.krishna@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1385553010-30183-3-git-send-email-l.krishna@samsung.com> Sender: linux-samsung-soc-owner@vger.kernel.org To: Leela Krishna Amudala , linux-samsung-soc@vger.kernel.org, wim@iguana.be Cc: dianders@chromium.org, kgene.kim@samsung.com, t.figa@samsung.com, devicetree@vger.kernel.org, linux-watchdog@vger.kernel.org, cpgs@samsung.com List-Id: devicetree@vger.kernel.org On 11/27/2013 03:50 AM, Leela Krishna Amudala wrote: > Add device tree support for exynos5250 and 5420 SoCs and use syscon regmap interface > to configure AUTOMATIC_WDT_RESET_DISABLE and MASK_WDT_RESET_REQUEST registers of PMU > to mask/unmask enable/disable of watchdog in probe and s2r scenarios. > > Signed-off-by: Leela Krishna Amudala > --- > .../devicetree/bindings/watchdog/samsung-wdt.txt | 21 ++- > drivers/watchdog/Kconfig | 1 + > drivers/watchdog/s3c2410_wdt.c | 164 ++++++++++++++++++-- > 3 files changed, 176 insertions(+), 10 deletions(-) > > diff --git a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt > index 2aa486c..cfff375 100644 > --- a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt > +++ b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt > @@ -5,10 +5,29 @@ after a preset amount of time during which the WDT reset event has not > occurred. > > Required properties: > -- compatible : should be "samsung,s3c2410-wdt" > +- compatible : should be one among the following > + (a) "samsung,s3c2410-wdt" for Exynos4 and previous SoCs > + (b) "samsung,exynos5250-wdt" for Exynos5250 > + (c) "samsung,exynos5420-wdt" for Exynos5420 > + > - reg : base physical address of the controller and length of memory mapped > region. > - interrupts : interrupt number to the cpu. > +- samsung,syscon-phandle : reference to syscon node (This property required only > + in case of compatible being "samsung,exynos5250-wdt" or "samsung,exynos5420-wdt". > + In case of Exynos5250 and 5420 this property points to syscon node holding the PMU > + base address) > > Optional properties: > - timeout-sec : contains the watchdog timeout in seconds. > + > +Example: > + > +watchdog@101D0000 { > + compatible = "samsung,exynos5250-wdt"; > + reg = <0x101D0000 0x100>; > + interrupts = <0 42 0>; > + clocks = <&clock 336>; > + clock-names = "watchdog"; > + samsung,syscon-phandle = <&pmu_syscon>; > +}; > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index 5be6e91..24738c0 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -188,6 +188,7 @@ config S3C2410_WATCHDOG > tristate "S3C2410 Watchdog" > depends on HAVE_S3C2410_WATCHDOG > select WATCHDOG_CORE > + select MFD_SYSCON if ARCH_EXYNOS5 > help > Watchdog timer block in the Samsung SoCs. This will reboot > the system when the timer expires with the watchdog enabled. > diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c > index 7d8fd04..b00b535 100644 > --- a/drivers/watchdog/s3c2410_wdt.c > +++ b/drivers/watchdog/s3c2410_wdt.c > @@ -40,6 +40,8 @@ > #include > #include > #include > +#include > +#include > > #define S3C2410_WTCON 0x00 > #define S3C2410_WTDAT 0x04 > @@ -60,6 +62,10 @@ > #define CONFIG_S3C2410_WATCHDOG_ATBOOT (0) > #define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME (15) > > +#define WDT_DISABLE_REG_OFFSET 0x0408 > +#define WDT_MASK_RESET_REG_OFFSET 0x040c > +#define QUIRK_NEEDS_PMU_CONFIG (1 << 0) > + > static bool nowayout = WATCHDOG_NOWAYOUT; > static int tmr_margin; > static int tmr_atboot = CONFIG_S3C2410_WATCHDOG_ATBOOT; > @@ -83,6 +89,25 @@ MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, " > "0 to reboot (default 0)"); > MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug (default 0)"); > > +/** > + * struct s3c2410_wdt_variant - Per-variant config data > + * > + * @disable_reg: Offset in pmureg for the register that disables the watchdog > + * timer reset functionality. > + * @mask_reset_reg: Offset in pmureg for the register that masks the watchdog > + * timer reset functionality. > + * @mask_bit: Bit number for the watchdog timer in the disable register and the > + * mask reset register. > + * @quirks: A bitfield of quirks. > + */ > + > +struct s3c2410_wdt_variant { > + int disable_reg; > + int mask_reset_reg; > + int mask_bit; > + u32 quirks; > +}; > + > struct s3c2410_wdt { > struct device *dev; > struct clk *clock; > @@ -93,8 +118,50 @@ struct s3c2410_wdt { > unsigned long wtdat_save; > struct watchdog_device wdt_device; > struct notifier_block freq_transition; > + struct s3c2410_wdt_variant *drv_data; > + struct regmap *pmureg; > +}; > + > +static const struct s3c2410_wdt_variant drv_data_s3c2410 = { > + .quirks = 0 > +}; > + > +#ifdef CONFIG_OF > +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 > +}; > + > +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 > }; > > +static const struct of_device_id s3c2410_wdt_match[] = { > + { .compatible = "samsung,s3c2410-wdt", > + .data = &drv_data_s3c2410 }, > + { .compatible = "samsung,exynos5250-wdt", > + .data = &drv_data_exynos5250 }, > + { .compatible = "samsung,exynos5420-wdt", > + .data = &drv_data_exynos5420 }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, s3c2410_wdt_match); > +#endif > + > +static const struct platform_device_id s3c2410_wdt_ids[] = { > + { > + .name = "s3c2410-wdt", > + .driver_data = (unsigned long)&drv_data_s3c2410, > + }, > + {} > +}; > +MODULE_DEVICE_TABLE(platform, s3c2410_wdt_ids); > + > /* watchdog control routines */ > > #define DBG(fmt, ...) \ > @@ -110,6 +177,32 @@ static inline struct s3c2410_wdt *freq_to_wdt(struct notifier_block *nb) > return container_of(nb, struct s3c2410_wdt, freq_transition); > } > > +static int s3c2410wdt_mask_and_disable_reset(struct s3c2410_wdt *wdt, bool mask) > +{ > + int ret; > + u32 mask_val = 1 << wdt->drv_data->mask_bit; > + u32 val = 0; > + > + if (mask) > + val = mask_val; > + > + ret = regmap_update_bits(wdt->pmureg, > + wdt->drv_data->disable_reg, > + mask_val, val); > + if (ret < 0) { > + dev_err(wdt->dev, "failed to update reg(%d)\n", ret); > + return ret; > + } > + Since you are now doing something in the error handler, you might want to follow coding style rules: if (ret < 0) goto error; > + ret = regmap_update_bits(wdt->pmureg, > + wdt->drv_data->mask_reset_reg, > + mask_val, val); error: > + if (ret < 0) > + dev_err(wdt->dev, "failed to update reg(%d)\n", ret); > + > + return ret; > +} > + > static int s3c2410wdt_keepalive(struct watchdog_device *wdd) > { > struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd); > @@ -331,6 +424,20 @@ static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt) > } > #endif > > +/* s3c2410_get_wdt_driver_data */ > +static inline struct s3c2410_wdt_variant * > +get_wdt_drv_data(struct platform_device *pdev) > +{ > + if (pdev->dev.of_node) { > + const struct of_device_id *match; > + match = of_match_node(s3c2410_wdt_match, pdev->dev.of_node); > + return (struct s3c2410_wdt_variant *)match->data; > + } else { > + return (struct s3c2410_wdt_variant *) > + platform_get_device_id(pdev)->driver_data; > + } > +} > + > static int s3c2410wdt_probe(struct platform_device *pdev) > { > struct device *dev; > @@ -353,6 +460,16 @@ static int s3c2410wdt_probe(struct platform_device *pdev) > spin_lock_init(&wdt->lock); > wdt->wdt_device = s3c2410_wdd; > > + wdt->drv_data = get_wdt_drv_data(pdev); > + if (wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG) { > + wdt->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node, > + "samsung,syscon-phandle"); > + if (IS_ERR(wdt->pmureg)) { > + dev_err(dev, "syscon regmap lookup failed.\n"); > + return PTR_ERR(wdt->pmureg); > + } > + } > + > wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); > if (wdt_irq == NULL) { > dev_err(dev, "no irq resource specified\n"); > @@ -421,6 +538,12 @@ static int s3c2410wdt_probe(struct platform_device *pdev) > goto err_cpufreq; > } > > + if (wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG) { > + ret = s3c2410wdt_mask_and_disable_reset(wdt, false); > + if (ret < 0) > + goto err_unregister; > + } > + > if (tmr_atboot && started == 0) { > dev_info(dev, "starting watchdog timer\n"); > s3c2410wdt_start(&wdt->wdt_device); > @@ -445,6 +568,9 @@ static int s3c2410wdt_probe(struct platform_device *pdev) > > return 0; > > + err_unregister: > + watchdog_unregister_device(&wdt->wdt_device); > + > err_cpufreq: > s3c2410wdt_cpufreq_deregister(wdt); > > @@ -458,8 +584,15 @@ static int s3c2410wdt_probe(struct platform_device *pdev) > > static int s3c2410wdt_remove(struct platform_device *dev) > { > + int ret; > struct s3c2410_wdt *wdt = platform_get_drvdata(dev); > > + if (wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG) { > + ret = s3c2410wdt_mask_and_disable_reset(wdt, true); > + if (ret < 0) > + return ret; > + } > + > watchdog_unregister_device(&wdt->wdt_device); > > s3c2410wdt_cpufreq_deregister(wdt); > @@ -472,8 +605,15 @@ static int s3c2410wdt_remove(struct platform_device *dev) > > static void s3c2410wdt_shutdown(struct platform_device *dev) > { > + int ret; > struct s3c2410_wdt *wdt = platform_get_drvdata(dev); > > + if (wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG) { > + ret = s3c2410wdt_mask_and_disable_reset(wdt, true); > + if (ret < 0) > + dev_warn(wdt->dev, "failed to update pmu register"); Duplicate error message. > + } > + > s3c2410wdt_stop(&wdt->wdt_device); > } > > @@ -481,12 +621,19 @@ static void s3c2410wdt_shutdown(struct platform_device *dev) > > static int s3c2410wdt_suspend(struct device *dev) > { > + int ret; > struct s3c2410_wdt *wdt = dev_get_drvdata(dev); > > /* Save watchdog state, and turn it off. */ > wdt->wtcon_save = readl(wdt->reg_base + S3C2410_WTCON); > wdt->wtdat_save = readl(wdt->reg_base + S3C2410_WTDAT); > > + if (wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG) { > + ret = s3c2410wdt_mask_and_disable_reset(wdt, true); > + if (ret < 0) > + return ret; > + } > + > /* Note that WTCNT doesn't need to be saved. */ > s3c2410wdt_stop(&wdt->wdt_device); > > @@ -495,6 +642,7 @@ static int s3c2410wdt_suspend(struct device *dev) > > static int s3c2410wdt_resume(struct device *dev) > { > + int ret; > struct s3c2410_wdt *wdt = dev_get_drvdata(dev); > > /* Restore watchdog state. */ > @@ -502,6 +650,12 @@ static int s3c2410wdt_resume(struct device *dev) > writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTCNT);/* Reset count */ > writel(wdt->wtcon_save, wdt->reg_base + S3C2410_WTCON); > > + if (wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG) { > + ret = s3c2410wdt_mask_and_disable_reset(wdt, false); > + if (ret < 0) > + return ret; > + } > + > dev_info(dev, "watchdog %sabled\n", > (wdt->wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis"); > > @@ -512,18 +666,11 @@ static int s3c2410wdt_resume(struct device *dev) > static SIMPLE_DEV_PM_OPS(s3c2410wdt_pm_ops, s3c2410wdt_suspend, > s3c2410wdt_resume); > > -#ifdef CONFIG_OF > -static const struct of_device_id s3c2410_wdt_match[] = { > - { .compatible = "samsung,s3c2410-wdt" }, > - {}, > -}; > -MODULE_DEVICE_TABLE(of, s3c2410_wdt_match); > -#endif > - > static struct platform_driver s3c2410wdt_driver = { > .probe = s3c2410wdt_probe, > .remove = s3c2410wdt_remove, > .shutdown = s3c2410wdt_shutdown, > + .id_table = s3c2410_wdt_ids, > .driver = { > .owner = THIS_MODULE, > .name = "s3c2410-wdt", > @@ -538,4 +685,3 @@ MODULE_AUTHOR("Ben Dooks , " > "Dimitry Andric "); > MODULE_DESCRIPTION("S3C2410 Watchdog Device Driver"); > MODULE_LICENSE("GPL"); > -MODULE_ALIAS("platform:s3c2410-wdt"); >