On Mon, Nov 18, 2013 at 03:19:48PM +0530, 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 <l.krishna@xxxxxxxxxxx>
> ---
> .../devicetree/bindings/watchdog/samsung-wdt.txt | 21 ++-
> drivers/watchdog/Kconfig | 1 +
> drivers/watchdog/s3c2410_wdt.c | 145 ++++++++++++++++++--
> 3 files changed, 157 insertions(+), 10 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
> index 2aa486c..5dea363 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_sys_reg>;
> +};
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index d1d53f3..0d272ae 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 23aad7c..42e0fd3 100644
> --- a/drivers/watchdog/s3c2410_wdt.c
> +++ b/drivers/watchdog/s3c2410_wdt.c
> @@ -41,6 +41,8 @@
> #include <linux/slab.h>
> #include <linux/err.h>
> #include <linux/of.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
>
> #define S3C2410_WTCON 0x00
> #define S3C2410_WTDAT 0x04
> @@ -61,6 +63,10 @@
> #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;
> @@ -84,6 +90,13 @@ 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 {
> + int disable_reg;
> + int mask_reset_reg;
> + int mask_bit;
> + u32 quirks;
> +};
> +
> struct s3c2410_wdt {
> struct device *dev;
> struct clk *clock;
> @@ -94,7 +107,49 @@ 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 */
>
> @@ -111,6 +166,26 @@ 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)
> + return ret;
> +
> + return regmap_update_bits(wdt->pmureg,
> + wdt->drv_data->mask_reset_reg,
> + mask_val, val);
> +}
> +
> static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
> {
> struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
> @@ -332,6 +407,20 @@ 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;
> @@ -354,6 +443,16 @@ 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");
> @@ -444,6 +543,14 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
> (wtcon & S3C2410_WTCON_RSTEN) ? "en" : "dis",
> (wtcon & S3C2410_WTCON_INTEN) ? "en" : "dis");
>
> + if (wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG) {
> + ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
> + if (ret < 0) {
> + dev_err(wdt->dev, "failed to update pmu register");
Hmm ... still not happy ;-). This message is the same for each call
to s3c2410wdt_mask_and_disable_reset(). Why not create it there ?
Sure, you'd have to decide if you want to use dev_warn() or dev_err(),
but that would still be better than repeating the same message (and code)
five times.
The same is true for the if() statement. It might be worthwhile calling
s3c2410wdt_mask_and_disable_reset() unconditionally and adding something
like
if (!(wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG))
return 0;
to it.
Thanks,
Guenter
> + goto err_cpufreq;
> + }
> + }
> +
> return 0;
>
> err_cpufreq:
> @@ -459,8 +566,15 @@ 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)
> + dev_warn(wdt->dev, "failed to update pmu register");
> + }
> +
> watchdog_unregister_device(&wdt->wdt_device);
>
> s3c2410wdt_cpufreq_deregister(wdt);
> @@ -473,8 +587,15 @@ 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");
> + }
> +
> s3c2410wdt_stop(&wdt->wdt_device);
> }
>
> @@ -482,12 +603,19 @@ 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)
> + dev_warn(wdt->dev, "failed to update pmu register");
> + }
> +
> /* Note that WTCNT doesn't need to be saved. */
> s3c2410wdt_stop(&wdt->wdt_device);
>
> @@ -496,6 +624,7 @@ 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. */
> @@ -503,6 +632,12 @@ 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)
> + dev_warn(wdt->dev, "failed to update pmu register");
> + }
> +
> dev_info(dev, "watchdog %sabled\n",
> (wdt->wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis");
>
> @@ -513,18 +648,11 @@ 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",
> @@ -540,4 +668,3 @@ MODULE_AUTHOR("Ben Dooks <ben@xxxxxxxxxxxx>, "
> MODULE_DESCRIPTION("S3C2410 Watchdog Device Driver");
> MODULE_LICENSE("GPL");
> MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
> -MODULE_ALIAS("platform:s3c2410-wdt");
> --
> 1.7.10.4
>
>
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