Re: [PATCH v4 04/11] watchdog: add support for sl28cpld watchdog

[Andy Shevchenko]

On Fri, Jun 5, 2020 at 12:14 AM Michael Walle <michael@xxxxxxxx> wrote:
>
> Add support for the watchdog of the sl28cpld board management
> controller. This is part of a multi-function device driver.

...

> +#include <linux/of_device.h>

Didn't find a user of this.

...

> +static bool nowayout = WATCHDOG_NOWAYOUT;
> +module_param(nowayout, bool, 0);
> +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
> +                               __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
> +
> +static int timeout;
> +module_param(timeout, int, 0);
> +MODULE_PARM_DESC(timeout, "Initial watchdog timeout in seconds");

Guenter ACKed this, but I'm wondering why we still need module parameters...

...

> +       int ret;
> +
> +       ret = regmap_read(wdt->regmap, wdt->offset + WDT_COUNT, &val);
> +
> +       return (ret < 0) ? 0 : val;

Besides extra parentheses and questionable ' < 0' part, the following
would look better I think

ret = ...
if (ret)
  return 0;

return val;

...

> +       int ret;
> +
> +       ret = regmap_write(wdt->regmap, wdt->offset + WDT_TIMEOUT, timeout);
> +       if (!ret)
> +               wdd->timeout = timeout;
> +
> +       return ret;

Similar story here:

ret = ...
if (ret)
  return ret;

wdd->... = ...
return 0;

...

> +       ret = regmap_read(wdt->regmap, wdt->offset + WDT_CTRL, &status);

> +       if (ret < 0)

What ' < 0' means? Do we have some positive return values?
Ditto for all your code.

> +               return ret;

...

> +       if (status & WDT_CTRL_EN) {
> +               sl28cpld_wdt_start(wdd);

> +               set_bit(WDOG_HW_RUNNING, &wdd->status);

Do you need atomic op here? Why?

> +       }

...

> +static const struct of_device_id sl28cpld_wdt_of_match[] = {
> +       { .compatible = "kontron,sl28cpld-wdt" },

> +       {},

No comma.

> +};

-- 
With Best Regards,
Andy Shevchenko