Re: [PATCH v5 03/10] watchdog: at91rm9200: use the system timer syscon

Guenter Roeck
2015-03-12T16:20:18Z

On Thu, Mar 12, 2015 at 01:07:27PM +0100, Alexandre Belloni wrote:
> Use a syscon regmap to access the system timer registers.
>
> Also, rename the driver atmel_st_watchdog to stop conflicting with
> at91sam9_wdt.c
>
> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
> drivers/watchdog/Kconfig | 2 +-
> drivers/watchdog/at91rm9200_wdt.c | 29 ++++++++++++++++++++++-------
> 2 files changed, 23 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 16f202350997..ce4f3a7f95fd 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -154,7 +154,7 @@ config ARM_SP805_WATCHDOG
>
> config AT91RM9200_WATCHDOG
> tristate "AT91RM9200 watchdog"
> - depends on SOC_AT91RM9200
> + depends on SOC_AT91RM9200 && MFD_SYSCON
> help
> Watchdog timer embedded into AT91RM9200 chips. This will reboot your
> system when the timeout is reached.
> diff --git a/drivers/watchdog/at91rm9200_wdt.c b/drivers/watchdog/at91rm9200_wdt.c
> index d244112d5b6f..e6fa87d85de3 100644
> --- a/drivers/watchdog/at91rm9200_wdt.c
> +++ b/drivers/watchdog/at91rm9200_wdt.c
> @@ -17,22 +17,25 @@
> #include <linux/init.h>
> #include <linux/io.h>
> #include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/mfd/syscon/atmel-st.h>
> #include <linux/miscdevice.h>
> #include <linux/module.h>
> #include <linux/moduleparam.h>
> #include <linux/platform_device.h>
> +#include <linux/regmap.h>
> #include <linux/types.h>
> #include <linux/watchdog.h>
> #include <linux/uaccess.h>
> #include <linux/of.h>
> #include <linux/of_device.h>
> -#include <mach/at91_st.h>
>
> #define WDT_DEFAULT_TIME 5 /* seconds */
> #define WDT_MAX_TIME 256 /* seconds */
>
> static int wdt_time = WDT_DEFAULT_TIME;
> static bool nowayout = WATCHDOG_NOWAYOUT;
> +static struct regmap *regmap_st;
>
> module_param(wdt_time, int, 0);
> MODULE_PARM_DESC(wdt_time, "Watchdog time in seconds. (default="
> @@ -55,7 +58,7 @@ static unsigned long at91wdt_busy;
> */
> static inline void at91_wdt_stop(void)
> {
> - at91_st_write(AT91_ST_WDMR, AT91_ST_EXTEN);
> + regmap_write(regmap_st, AT91_ST_WDMR, AT91_ST_EXTEN);
> }
>
> /*
> @@ -63,9 +66,9 @@ static inline void at91_wdt_stop(void)
> */
> static inline void at91_wdt_start(void)
> {
> - at91_st_write(AT91_ST_WDMR, AT91_ST_EXTEN | AT91_ST_RSTEN |
> + regmap_write(regmap_st, AT91_ST_WDMR, AT91_ST_EXTEN | AT91_ST_RSTEN |
> (((65536 * wdt_time) >> 8) & AT91_ST_WDV));
> - at91_st_write(AT91_ST_CR, AT91_ST_WDRST);
> + regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
> }
>
> /*
> @@ -73,7 +76,7 @@ static inline void at91_wdt_start(void)
> */
> static inline void at91_wdt_reload(void)
> {
> - at91_st_write(AT91_ST_CR, AT91_ST_WDRST);
> + regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
> }
>
> /* ......................................................................... */
> @@ -203,12 +206,24 @@ static struct miscdevice at91wdt_miscdev = {
>
> static int at91wdt_probe(struct platform_device *pdev)
> {
> + struct device *dev = &pdev->dev;
> + struct device *parent;
> int res;
>
> if (at91wdt_miscdev.parent)
> return -EBUSY;
> at91wdt_miscdev.parent = &pdev->dev;
>
> + parent = dev->parent;
> + if (!parent) {
> + dev_err(dev, "no parent\n");
> + return -ENODEV;
> + }
> +
> + regmap_st = syscon_node_to_regmap(parent->of_node);
> + if (!regmap_st)
> + return -ENODEV;
> +
> res = misc_register(&at91wdt_miscdev);
> if (res)
> return res;
> @@ -267,7 +282,7 @@ static struct platform_driver at91wdt_driver = {
> .suspend = at91wdt_suspend,
> .resume = at91wdt_resume,
> .driver = {
> - .name = "at91_wdt",
> + .name = "atmel_st_watchdog",
> .of_match_table = at91_wdt_dt_ids,
> },
> };
> @@ -296,4 +311,4 @@ module_exit(at91_wdt_exit);
> MODULE_AUTHOR("Andrew Victor");
> MODULE_DESCRIPTION("Watchdog driver for Atmel AT91RM9200");
> MODULE_LICENSE("GPL");
> -MODULE_ALIAS("platform:at91_wdt");
> +MODULE_ALIAS("platform:atmel_st_watchdog");
> --
> 2.1.0
>
> --
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