On Tue, Jul 09, 2019 at 08:09:05PM +0000, Melin Tomas wrote:
> Maximum and minimum timeout values depend on the actual input clock
> frequency and prescaler selection.
>
> Signed-off-by: Tomas Melin <tomas.melin@xxxxxxxxxxx>
> ---
> drivers/watchdog/cadence_wdt.c | 18 ++++++++++++------
> 1 file changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/watchdog/cadence_wdt.c b/drivers/watchdog/cadence_wdt.c
> index ddbf602bdc40..a0d7666e7d20 100644
> --- a/drivers/watchdog/cadence_wdt.c
> +++ b/drivers/watchdog/cadence_wdt.c
> @@ -18,9 +18,6 @@
> #include <linux/watchdog.h>
>
> #define CDNS_WDT_DEFAULT_TIMEOUT 10
> -/* Supports 1 - 516 sec */
> -#define CDNS_WDT_MIN_TIMEOUT 1
> -#define CDNS_WDT_MAX_TIMEOUT 516
>
> /* Restart key */
> #define CDNS_WDT_RESTART_KEY 0x00001999
> @@ -28,6 +25,10 @@
> /* Counter register access key */
> #define CDNS_WDT_REGISTER_ACCESS_KEY 0x00920000
>
> +/* Counter control register, counter restart values */
> +#define CDNS_WDT_CCR_CRV_MIN 0xFFF
> +#define CDNS_WDT_CCR_CRV_MAX 0xFFFFFF
^ Please use tabs here
> +
> /* Counter value divisor */
> #define CDNS_WDT_COUNTER_VALUE_DIVISOR 0x1000
>
> @@ -317,7 +318,10 @@ static int cdns_wdt_probe(struct platform_device *pdev)
> return ret;
>
> clock_f = clk_get_rate(wdt->clk);
> - if (clock_f <= CDNS_WDT_CLK_75MHZ) {
> + if (clock_f == 0) {
> + dev_err(dev, "invalid clock frequency, (f=%lu)\n", clock_f);
We know that clock_f is 0 here. No need to use %lu.
> + return -EINVAL;
else after return is unnecessary (and static checkers will rightfully complain).
> + } else if (clock_f <= CDNS_WDT_CLK_75MHZ) {
> wdt->prescaler = CDNS_WDT_PRESCALE_512;
> wdt->ctrl_clksel = CDNS_WDT_PRESCALE_SELECT_512;
> } else {
> @@ -329,8 +333,10 @@ static int cdns_wdt_probe(struct platform_device *pdev)
> cdns_wdt_device->info = &cdns_wdt_info;
> cdns_wdt_device->ops = &cdns_wdt_ops;
> cdns_wdt_device->timeout = CDNS_WDT_DEFAULT_TIMEOUT;
> - cdns_wdt_device->min_timeout = CDNS_WDT_MIN_TIMEOUT;
> - cdns_wdt_device->max_timeout = CDNS_WDT_MAX_TIMEOUT;
> + cdns_wdt_device->min_timeout =
> + CDNS_WDT_CCR_CRV_MIN * wdt->prescaler / clock_f;
> + cdns_wdt_device->max_timeout =
> + CDNS_WDT_CCR_CRV_MAX * wdt->prescaler / clock_f;
>
> wdt->regs = devm_platform_ioremap_resource(pdev, 0);
> if (IS_ERR(wdt->regs))
> --
> 2.17.2
>
