| Message ID | 20190709200801.42313-3-tomas.melin@vaisala.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | watchdog: cadence_wdt: Support all available prescaler values | expand |
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@vaisala.com> > --- > 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 >
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 + /* 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); + return -EINVAL; + } 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))
Maximum and minimum timeout values depend on the actual input clock frequency and prescaler selection. Signed-off-by: Tomas Melin <tomas.melin@vaisala.com> --- drivers/watchdog/cadence_wdt.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)