diff mbox series

[v1,10/11] watchdog: bd9576_wdt: switch to using devm_fwnode_gpiod_get()

Message ID 20220903-gpiod_get_from_of_node-remove-v1-10-b29adfb27a6c@gmail.com (mailing list archive)
State Accepted
Commit 4f719022a753bb15720c9ddeb0387a93caa372ce
Headers show
Series Get rid of [devm_]gpiod_get_from_of_node() public APIs | expand

Commit Message

Dmitry Torokhov Sept. 5, 2022, 6:31 a.m. UTC
I would like to stop exporting OF-specific devm_gpiod_get_from_of_node()
so that gpiolib can be cleaned a bit, so let's switch to the generic
fwnode property API.

While at it switch the rest of the calls to read properties in
bd9576_wdt_probe() to the generic device property API as well.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Comments

Andy Shevchenko Sept. 5, 2022, 11:09 a.m. UTC | #1
On Mon, Sep 5, 2022 at 9:33 AM Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:
>
> I would like to stop exporting OF-specific devm_gpiod_get_from_of_node()
> so that gpiolib can be cleaned a bit, so let's switch to the generic
> fwnode property API.
>
> While at it switch the rest of the calls to read properties in

it, switch

> bd9576_wdt_probe() to the generic device property API as well.

...

>         struct device *dev = &pdev->dev;

struct device *parent = dev->parent;

can make your code slightly neater.

...

> +       count = device_property_count_u32(dev->parent, "rohm,hw-timeout-ms");
> +       if (count < 0 && count != -EINVAL)
> +               return count;
> +
> +       if (count > 0) {

> +               if (count > ARRAY_SIZE(hw_margin))
> +                       return -EINVAL;

Why double check? You may move it out of the (count > 0).

...

> -       if (ret == 1)
> -               hw_margin_max = hw_margin[0];

> +               ret = device_property_read_u32_array(dev->parent,
> +                                                    "rohm,hw-timeout-ms",
> +                                                    hw_margin, count);
> +               if (ret < 0)
> +                       return ret;

So, only this needs the count > 0 check since below already has it implicitly.

> -       if (ret == 2) {
> -               hw_margin_max = hw_margin[1];
> -               hw_margin_min = hw_margin[0];
> +               if (count == 1)
> +                       hw_margin_max = hw_margin[0];
> +
> +               if (count == 2) {
> +                       hw_margin_max = hw_margin[1];
> +                       hw_margin_min = hw_margin[0];
> +               }
>         }
Guenter Roeck Sept. 5, 2022, 3:13 p.m. UTC | #2
On 9/5/22 04:09, Andy Shevchenko wrote:
> On Mon, Sep 5, 2022 at 9:33 AM Dmitry Torokhov
> <dmitry.torokhov@gmail.com> wrote:
>>
>> I would like to stop exporting OF-specific devm_gpiod_get_from_of_node()
>> so that gpiolib can be cleaned a bit, so let's switch to the generic
>> fwnode property API.
>>
>> While at it switch the rest of the calls to read properties in
> 
> it, switch
> 
>> bd9576_wdt_probe() to the generic device property API as well.
> 
> ...
> 
>>          struct device *dev = &pdev->dev;
> 
> struct device *parent = dev->parent;
> 
> can make your code slightly neater.
> 
> ...
> 
>> +       count = device_property_count_u32(dev->parent, "rohm,hw-timeout-ms");
>> +       if (count < 0 && count != -EINVAL)
>> +               return count;
>> +
>> +       if (count > 0) {
> 
>> +               if (count > ARRAY_SIZE(hw_margin))
>> +                       return -EINVAL;
> 
> Why double check? You may move it out of the (count > 0).
> 

Two checks will always be needed, so I don't entirely see
how that would be better.

> ...
> 
>> -       if (ret == 1)
>> -               hw_margin_max = hw_margin[0];
> 
>> +               ret = device_property_read_u32_array(dev->parent,
>> +                                                    "rohm,hw-timeout-ms",
>> +                                                    hw_margin, count);
>> +               if (ret < 0)
>> +                       return ret;
> 
> So, only this needs the count > 0 check since below already has it implicitly.
> 
Sorry, I don't understand this comment.

Guenter

>> -       if (ret == 2) {
>> -               hw_margin_max = hw_margin[1];
>> -               hw_margin_min = hw_margin[0];
>> +               if (count == 1)
>> +                       hw_margin_max = hw_margin[0];
>> +
>> +               if (count == 2) {
>> +                       hw_margin_max = hw_margin[1];
>> +                       hw_margin_min = hw_margin[0];
>> +               }
>>          }
>
Andy Shevchenko Sept. 5, 2022, 3:21 p.m. UTC | #3
On Mon, Sep 5, 2022 at 6:13 PM Guenter Roeck <linux@roeck-us.net> wrote:
> On 9/5/22 04:09, Andy Shevchenko wrote:
> > On Mon, Sep 5, 2022 at 9:33 AM Dmitry Torokhov
> > <dmitry.torokhov@gmail.com> wrote:

...

> >> +       count = device_property_count_u32(dev->parent, "rohm,hw-timeout-ms");
> >> +       if (count < 0 && count != -EINVAL)
> >> +               return count;
> >> +
> >> +       if (count > 0) {
> >
> >> +               if (count > ARRAY_SIZE(hw_margin))
> >> +                       return -EINVAL;
> >
> > Why double check? You may move it out of the (count > 0).
>
> Two checks will always be needed, so I don't entirely see
> how that would be better.

But not nested. That's my point:

if (count > ARRAY_SIZE())
  return ...
if (count > 0)
  ...

> >> -       if (ret == 1)
> >> -               hw_margin_max = hw_margin[0];
> >
> >> +               ret = device_property_read_u32_array(dev->parent,
> >> +                                                    "rohm,hw-timeout-ms",
> >> +                                                    hw_margin, count);
> >> +               if (ret < 0)
> >> +                       return ret;
> >
> > So, only this needs the count > 0 check since below already has it implicitly.
> >
> Sorry, I don't understand this comment.

if (count > 0) {
  ret = device_property_read_u32_array(...);
  ...
}
if (count == 1)
 ...
if (count == 2)
 ...

But here it might be better to have the nested conditionals.

> >> -       if (ret == 2) {
> >> -               hw_margin_max = hw_margin[1];
> >> -               hw_margin_min = hw_margin[0];
> >> +               if (count == 1)
> >> +                       hw_margin_max = hw_margin[0];
> >> +
> >> +               if (count == 2) {
> >> +                       hw_margin_max = hw_margin[1];
> >> +                       hw_margin_min = hw_margin[0];
> >> +               }
> >>          }
Guenter Roeck Sept. 5, 2022, 3:49 p.m. UTC | #4
On 9/5/22 08:21, Andy Shevchenko wrote:
> On Mon, Sep 5, 2022 at 6:13 PM Guenter Roeck <linux@roeck-us.net> wrote:
>> On 9/5/22 04:09, Andy Shevchenko wrote:
>>> On Mon, Sep 5, 2022 at 9:33 AM Dmitry Torokhov
>>> <dmitry.torokhov@gmail.com> wrote:
> 
> ...
> 
>>>> +       count = device_property_count_u32(dev->parent, "rohm,hw-timeout-ms");
>>>> +       if (count < 0 && count != -EINVAL)
>>>> +               return count;
>>>> +
>>>> +       if (count > 0) {
>>>
>>>> +               if (count > ARRAY_SIZE(hw_margin))
>>>> +                       return -EINVAL;
>>>
>>> Why double check? You may move it out of the (count > 0).
>>
>> Two checks will always be needed, so I don't entirely see
>> how that would be better.
> 
> But not nested. That's my point:
> 
> if (count > ARRAY_SIZE())
>    return ...
> if (count > 0)
>    ...
> 

The old code has either 1 or two checks if there is no error.
Your suggested code has always two checks. I don't see how that
is an improvement.

>>>> -       if (ret == 1)
>>>> -               hw_margin_max = hw_margin[0];
>>>
>>>> +               ret = device_property_read_u32_array(dev->parent,
>>>> +                                                    "rohm,hw-timeout-ms",
>>>> +                                                    hw_margin, count);
>>>> +               if (ret < 0)
>>>> +                       return ret;
>>>
>>> So, only this needs the count > 0 check since below already has it implicitly.
>>>
>> Sorry, I don't understand this comment.
> 
> if (count > 0) {
>    ret = device_property_read_u32_array(...);
>    ...
> }
> if (count == 1)
>   ...
> if (count == 2)
>   ...
> 
> But here it might be better to have the nested conditionals.
> 

We know that count is either 1 or 2 here, so strictly speaking
	if (count == 1) {
	} else {
	}
would be sufficient. On the other side, that depends on ARRAY_SIZE() being
exactly 2, so
	if (count == 1) {
	} else if (count == 2) {
	}
would also make sense. Either way is fine with me. I'll leave it up
to Dmitry to decide what he wants to do.

Thanks,
Guenter

>>>> -       if (ret == 2) {
>>>> -               hw_margin_max = hw_margin[1];
>>>> -               hw_margin_min = hw_margin[0];
>>>> +               if (count == 1)
>>>> +                       hw_margin_max = hw_margin[0];
>>>> +
>>>> +               if (count == 2) {
>>>> +                       hw_margin_max = hw_margin[1];
>>>> +                       hw_margin_min = hw_margin[0];
>>>> +               }
>>>>           }
>
Dmitry Torokhov Sept. 5, 2022, 7:47 p.m. UTC | #5
On Mon, Sep 05, 2022 at 08:49:58AM -0700, Guenter Roeck wrote:
> On 9/5/22 08:21, Andy Shevchenko wrote:
> > On Mon, Sep 5, 2022 at 6:13 PM Guenter Roeck <linux@roeck-us.net> wrote:
> > > On 9/5/22 04:09, Andy Shevchenko wrote:
> > > > On Mon, Sep 5, 2022 at 9:33 AM Dmitry Torokhov
> > > > <dmitry.torokhov@gmail.com> wrote:
> > 
> > ...
> > 
> > > > > +       count = device_property_count_u32(dev->parent, "rohm,hw-timeout-ms");
> > > > > +       if (count < 0 && count != -EINVAL)
> > > > > +               return count;
> > > > > +
> > > > > +       if (count > 0) {
> > > > 
> > > > > +               if (count > ARRAY_SIZE(hw_margin))
> > > > > +                       return -EINVAL;
> > > > 
> > > > Why double check? You may move it out of the (count > 0).
> >
> > > Two checks will always be needed, so I don't entirely see
> > > how that would be better.
> > 
> > But not nested. That's my point:
> > 
> > if (count > ARRAY_SIZE())
> >    return ...
> > if (count > 0)
> >    ...
> > 
> 
> The old code has either 1 or two checks if there is no error.
> Your suggested code has always two checks. I don't see how that
> is an improvement.
> 
> > > > > -       if (ret == 1)
> > > > > -               hw_margin_max = hw_margin[0];
> > > > 
> > > > > +               ret = device_property_read_u32_array(dev->parent,
> > > > > +                                                    "rohm,hw-timeout-ms",
> > > > > +                                                    hw_margin, count);
> > > > > +               if (ret < 0)
> > > > > +                       return ret;
> > > > 
> > > > So, only this needs the count > 0 check since below already has it implicitly.
> > > > 
> > > Sorry, I don't understand this comment.
> > 
> > if (count > 0) {
> >    ret = device_property_read_u32_array(...);
> >    ...
> > }
> > if (count == 1)
> >   ...
> > if (count == 2)
> >   ...
> > 
> > But here it might be better to have the nested conditionals.
> > 
> 
> We know that count is either 1 or 2 here, so strictly speaking
> 	if (count == 1) {
> 	} else {
> 	}
> would be sufficient. On the other side, that depends on ARRAY_SIZE() being
> exactly 2, so
> 	if (count == 1) {
> 	} else if (count == 2) {
> 	}
> would also make sense. Either way is fine with me. I'll leave it up
> to Dmitry to decide what he wants to do.

My goal is to drop usage of devm_gpiod_get_from_of_node(), beyond that I
do not have strong preferences either way really. It is probing code, so
performance is not critical, but I'm obviously satisfied with how the
code looks now, or I would not have sent it.

Thanks.
Guenter Roeck Sept. 5, 2022, 10:09 p.m. UTC | #6
On 9/5/22 12:47, Dmitry Torokhov wrote:
[ ... ]
>> We know that count is either 1 or 2 here, so strictly speaking
>> 	if (count == 1) {
>> 	} else {
>> 	}
>> would be sufficient. On the other side, that depends on ARRAY_SIZE() being
>> exactly 2, so
>> 	if (count == 1) {
>> 	} else if (count == 2) {
>> 	}
>> would also make sense. Either way is fine with me. I'll leave it up
>> to Dmitry to decide what he wants to do.
> 
> My goal is to drop usage of devm_gpiod_get_from_of_node(), beyond that I
> do not have strong preferences either way really. It is probing code, so
> performance is not critical, but I'm obviously satisfied with how the
> code looks now, or I would not have sent it.
> 

Good point.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Dmitry Torokhov Sept. 7, 2022, 2 a.m. UTC | #7
On Mon, Sep 05, 2022 at 03:09:05PM -0700, Guenter Roeck wrote:
> On 9/5/22 12:47, Dmitry Torokhov wrote:
> [ ... ]
> > > We know that count is either 1 or 2 here, so strictly speaking
> > > 	if (count == 1) {
> > > 	} else {
> > > 	}
> > > would be sufficient. On the other side, that depends on ARRAY_SIZE() being
> > > exactly 2, so
> > > 	if (count == 1) {
> > > 	} else if (count == 2) {
> > > 	}
> > > would also make sense. Either way is fine with me. I'll leave it up
> > > to Dmitry to decide what he wants to do.
> > 
> > My goal is to drop usage of devm_gpiod_get_from_of_node(), beyond that I
> > do not have strong preferences either way really. It is probing code, so
> > performance is not critical, but I'm obviously satisfied with how the
> > code looks now, or I would not have sent it.
> > 
> 
> Good point.
> 
> Reviewed-by: Guenter Roeck <linux@roeck-us.net>

Guenter, individual patches are going through maintainer's trees, will
you take this one?

Thanks.
Linus Walleij Sept. 8, 2022, 8:38 a.m. UTC | #8
On Mon, Sep 5, 2022 at 8:31 AM Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:

> I would like to stop exporting OF-specific devm_gpiod_get_from_of_node()
> so that gpiolib can be cleaned a bit, so let's switch to the generic
> fwnode property API.
>
> While at it switch the rest of the calls to read properties in
> bd9576_wdt_probe() to the generic device property API as well.
>
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij
diff mbox series

Patch

diff --git a/drivers/watchdog/bd9576_wdt.c b/drivers/watchdog/bd9576_wdt.c
index 0b6999f3b6e8..4a20e07fbb69 100644
--- a/drivers/watchdog/bd9576_wdt.c
+++ b/drivers/watchdog/bd9576_wdt.c
@@ -9,8 +9,8 @@ 
 #include <linux/gpio/consumer.h>
 #include <linux/mfd/rohm-bd957x.h>
 #include <linux/module.h>
-#include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/watchdog.h>
 
@@ -202,10 +202,10 @@  static int bd957x_set_wdt_mode(struct bd9576_wdt_priv *priv, int hw_margin,
 static int bd9576_wdt_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	struct device_node *np = dev->parent->of_node;
 	struct bd9576_wdt_priv *priv;
 	u32 hw_margin[2];
 	u32 hw_margin_max = BD957X_WDT_DEFAULT_MARGIN, hw_margin_min = 0;
+	int count;
 	int ret;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
@@ -221,40 +221,51 @@  static int bd9576_wdt_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	priv->gpiod_en = devm_gpiod_get_from_of_node(dev, dev->parent->of_node,
-						     "rohm,watchdog-enable-gpios",
-						     0, GPIOD_OUT_LOW,
-						     "watchdog-enable");
+	priv->gpiod_en = devm_fwnode_gpiod_get(dev, dev_fwnode(dev->parent),
+					       "rohm,watchdog-enable",
+					       GPIOD_OUT_LOW,
+					       "watchdog-enable");
 	if (IS_ERR(priv->gpiod_en))
 		return dev_err_probe(dev, PTR_ERR(priv->gpiod_en),
 			      "getting watchdog-enable GPIO failed\n");
 
-	priv->gpiod_ping = devm_gpiod_get_from_of_node(dev, dev->parent->of_node,
-						     "rohm,watchdog-ping-gpios",
-						     0, GPIOD_OUT_LOW,
-						     "watchdog-ping");
+	priv->gpiod_ping = devm_fwnode_gpiod_get(dev, dev_fwnode(dev->parent),
+						 "rohm,watchdog-ping",
+						 GPIOD_OUT_LOW,
+						 "watchdog-ping");
 	if (IS_ERR(priv->gpiod_ping))
 		return dev_err_probe(dev, PTR_ERR(priv->gpiod_ping),
 				     "getting watchdog-ping GPIO failed\n");
 
-	ret = of_property_read_variable_u32_array(np, "rohm,hw-timeout-ms",
-						  &hw_margin[0], 1, 2);
-	if (ret < 0 && ret != -EINVAL)
-		return ret;
+	count = device_property_count_u32(dev->parent, "rohm,hw-timeout-ms");
+	if (count < 0 && count != -EINVAL)
+		return count;
+
+	if (count > 0) {
+		if (count > ARRAY_SIZE(hw_margin))
+			return -EINVAL;
 
-	if (ret == 1)
-		hw_margin_max = hw_margin[0];
+		ret = device_property_read_u32_array(dev->parent,
+						     "rohm,hw-timeout-ms",
+						     hw_margin, count);
+		if (ret < 0)
+			return ret;
 
-	if (ret == 2) {
-		hw_margin_max = hw_margin[1];
-		hw_margin_min = hw_margin[0];
+		if (count == 1)
+			hw_margin_max = hw_margin[0];
+
+		if (count == 2) {
+			hw_margin_max = hw_margin[1];
+			hw_margin_min = hw_margin[0];
+		}
 	}
 
 	ret = bd957x_set_wdt_mode(priv, hw_margin_max, hw_margin_min);
 	if (ret)
 		return ret;
 
-	priv->always_running = of_property_read_bool(np, "always-running");
+	priv->always_running = device_property_read_bool(dev->parent,
+							 "always-running");
 
 	watchdog_set_drvdata(&priv->wdd, priv);