[PATCH v7 4/6] watchdog: pnx4008: restart: support "cmd" from userspace

[linux@roeck-us.net (Guenter Roeck)]

On Fri, Mar 04, 2016 at 01:44:08PM -0500, Sylvain Lemieux wrote:
> From: Sylvain Lemieux <slemieux@tycoint.com>
> 
> Added support to verify if a "cmd" is passed from the userspace program rebooting the system;
> - if a valid "cmd" is available, handle it;
> - If the received "cmd" is not supported, use the default reboot mode.
> 
> Signed-off-by: Sylvain Lemieux <slemieux@tycoint.com>

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

> ---
> Changes from v6 to v7:
> - remove typecast.
> 
> Changes from v5 to v6:
> - remove typecast.
> 
> Changes from v4 to v5:
> - no logical change; updated to work with new revision of patch #2.
> 
> Changes from v3 to v4:
> - none.
> 
> Changes from v2 to v3:
> - no logical change; updated to work with new revision of patch #2.
> 
> Changes from v1 to v2:
> - Rename patch title;
>   was "arm: lpc32xx: restart: support "cmd" from userspace"
> - Add change to "pnx-4008" driver instead of "mach-lpc32xx".
> 
>  drivers/watchdog/pnx4008_wdt.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/watchdog/pnx4008_wdt.c b/drivers/watchdog/pnx4008_wdt.c
> index 51be66e..0529aed 100644
> --- a/drivers/watchdog/pnx4008_wdt.c
> +++ b/drivers/watchdog/pnx4008_wdt.c
> @@ -129,6 +129,21 @@ static int pnx4008_wdt_set_timeout(struct watchdog_device *wdd,
>  static int pnx4008_restart_handler(struct watchdog_device *wdd,
>  				   unsigned long mode, void *cmd)
>  {
> +	const char *boot_cmd = cmd;
> +
> +	/*
> +	 * Verify if a "cmd" passed from the userspace program rebooting
> +	 * the system; if available, handle it.
> +	 * - For details, see the 'reboot' syscall in kernel/reboot.c
> +	 * - If the received "cmd" is not supported, use the default mode.
> +	 */
> +	if (boot_cmd) {
> +		if (boot_cmd[0] == 'h')
> +			mode = REBOOT_HARD;
> +		else if (boot_cmd[0] == 's')
> +			mode = REBOOT_SOFT;
> +	}
> +
>  	if (mode == REBOOT_SOFT) {
>  		/* Force match output active */
>  		writel(EXT_MATCH0, WDTIM_EMR(wdt_base));
> -- 
> 1.8.3.1
>