Re: [RFC PATCH v3] watchdog: sp805: Add clock-frequency property

[Srinath Mannam <srinath.mannam@broadcom.com>]

Hi Guenter,

I will send the updated patch..
Thank you.

Regards,
Srinath.

On Sat, Jul 21, 2018 at 8:08 PM, Guenter Roeck <linux@roeck-us.net> wrote:
> On 07/10/2018 01:44 AM, Srinath Mannam wrote:
>>
>> When using ACPI node, binding clock devices are
>> not available as device tree, So clock-frequency
>> property given in _DSD object of ACPI device is
>> used to calculate Watchdog rate.
>>
>> Signed-off-by: Srinath Mannam <srinath.mannam@broadcom.com>
>
>
> Please resend as non-RFC and add a note in the description indicating
> that there is no formal review process for _DSD properties.
>
> Thanks,
> Guenter
>
>> ---
>>   drivers/watchdog/sp805_wdt.c | 35 +++++++++++++++++++++++++----------
>>   1 file changed, 25 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
>> index 9849db0..a896b1c 100644
>> --- a/drivers/watchdog/sp805_wdt.c
>> +++ b/drivers/watchdog/sp805_wdt.c
>> @@ -11,6 +11,7 @@
>>    * warranty of any kind, whether express or implied.
>>    */
>>   +#include <linux/acpi.h>
>>   #include <linux/device.h>
>>   #include <linux/resource.h>
>>   #include <linux/amba/bus.h>
>> @@ -22,6 +23,7 @@
>>   #include <linux/math64.h>
>>   #include <linux/module.h>
>>   #include <linux/moduleparam.h>
>> +#include <linux/of.h>
>>   #include <linux/pm.h>
>>   #include <linux/slab.h>
>>   #include <linux/spinlock.h>
>> @@ -65,6 +67,7 @@ struct sp805_wdt {
>>         spinlock_t                      lock;
>>         void __iomem                    *base;
>>         struct clk                      *clk;
>> +       u64                             rate;
>>         struct amba_device              *adev;
>>         unsigned int                    load_val;
>>   };
>> @@ -80,7 +83,7 @@ static int wdt_setload(struct watchdog_device *wdd,
>> unsigned int timeout)
>>         struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
>>         u64 load, rate;
>>   -     rate = clk_get_rate(wdt->clk);
>> +       rate = wdt->rate;
>>         /*
>>          * sp805 runs counter with given value twice, after the end of
>> first
>> @@ -106,9 +109,7 @@ static int wdt_setload(struct watchdog_device *wdd,
>> unsigned int timeout)
>>   static unsigned int wdt_timeleft(struct watchdog_device *wdd)
>>   {
>>         struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
>> -       u64 load, rate;
>> -
>> -       rate = clk_get_rate(wdt->clk);
>> +       u64 load;
>>         spin_lock(&wdt->lock);
>>         load = readl_relaxed(wdt->base + WDTVALUE);
>> @@ -118,7 +119,7 @@ static unsigned int wdt_timeleft(struct
>> watchdog_device *wdd)
>>                 load += wdt->load_val + 1;
>>         spin_unlock(&wdt->lock);
>>   -     return div_u64(load, rate);
>> +       return div_u64(load, wdt->rate);
>>   }
>>     static int
>> @@ -228,11 +229,25 @@ sp805_wdt_probe(struct amba_device *adev, const
>> struct amba_id *id)
>>         if (IS_ERR(wdt->base))
>>                 return PTR_ERR(wdt->base);
>>   -     wdt->clk = devm_clk_get(&adev->dev, NULL);
>> -       if (IS_ERR(wdt->clk)) {
>> -               dev_warn(&adev->dev, "Clock not found\n");
>> -               ret = PTR_ERR(wdt->clk);
>> -               goto err;
>> +       if (adev->dev.of_node) {
>> +               wdt->clk = devm_clk_get(&adev->dev, NULL);
>> +               if (IS_ERR(wdt->clk)) {
>> +                       dev_err(&adev->dev, "Clock not found\n");
>> +                       return PTR_ERR(wdt->clk);
>> +               }
>> +               wdt->rate = clk_get_rate(wdt->clk);
>> +       } else if (has_acpi_companion(&adev->dev)) {
>> +               /*
>> +                * When Driver probe with ACPI device, clock devices
>> +                * are not available, so watchdog rate get from
>> +                * clock-frequency property given in _DSD object.
>> +                */
>> +               device_property_read_u64(&adev->dev, "clock-frequency",
>> +                                        &wdt->rate);
>> +               if (!wdt->rate) {
>> +                       dev_err(&adev->dev, "no clock-frequency
>> property\n");
>> +                       return -ENODEV;
>> +               }
>>         }
>>         wdt->adev = adev;
>>
>