From: Andy Shevchenko <[email protected]>
On STM32MP1, the GPIO banks are subnodes of pin-controller@50002000,
see arch/arm/boot/dts/stm32mp151.dtsi. The driver for
pin-controller@50002000 is in drivers/pinctrl/stm32/pinctrl-stm32.c
and iterates over all of its DT subnodes when registering each GPIO
bank gpiochip. Each gpiochip has:
- gpio_chip.parent = dev,
where dev is the device node of the pin controller
- gpio_chip.of_node = np,
which is the OF node of the GPIO bank
Therefore, dev_fwnode(chip->parent) != of_fwnode_handle(chip.of_node),
i.e. pin-controller@50002000 != pin-controller@50002000/gpio@5000*000.
The original code behaved correctly, as it extracted the "gpio-line-names"
from of_fwnode_handle(chip.of_node) = pin-controller@50002000/gpio@5000*000.
To achieve the same behaviour, read property from the firmware node.
Fixes: 7cba1a4d5e162 ("gpiolib: generalize devprop_gpiochip_set_names() for device properties")
Cc: [email protected]
Reported-by: Marek Vasut <[email protected]>
Reported-by: Roman Guskov <[email protected]>
Signed-off-by: Andy Shevchenko <[email protected]>
Tested-by: Marek Vasut <[email protected]>
Reviewed-by: Marek Vasut <[email protected]>
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
Hi Greg,
This patch somehow got lost and never made its way into stable. Could you
please apply it?
Thanks,
Bartosz
drivers/gpio/gpiolib.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 4253837f870b..7ec0822c0505 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -367,22 +367,18 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc)
*
* Looks for device property "gpio-line-names" and if it exists assigns
* GPIO line names for the chip. The memory allocated for the assigned
- * names belong to the underlying software node and should not be released
+ * names belong to the underlying firmware node and should not be released
* by the caller.
*/
static int devprop_gpiochip_set_names(struct gpio_chip *chip)
{
struct gpio_device *gdev = chip->gpiodev;
- struct device *dev = chip->parent;
+ struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev);
const char **names;
int ret, i;
int count;
- /* GPIO chip may not have a parent device whose properties we inspect. */
- if (!dev)
- return 0;
-
- count = device_property_string_array_count(dev, "gpio-line-names");
+ count = fwnode_property_string_array_count(fwnode, "gpio-line-names");
if (count < 0)
return 0;
@@ -396,7 +392,7 @@ static int devprop_gpiochip_set_names(struct gpio_chip *chip)
if (!names)
return -ENOMEM;
- ret = device_property_read_string_array(dev, "gpio-line-names",
+ ret = fwnode_property_read_string_array(fwnode, "gpio-line-names",
names, count);
if (ret < 0) {
dev_warn(&gdev->dev, "failed to read GPIO line names\n");
--
2.30.1
On Sat, Apr 10, 2021 at 11:09:19AM +0200, Bartosz Golaszewski wrote:
> From: Andy Shevchenko <[email protected]>
>
> On STM32MP1, the GPIO banks are subnodes of pin-controller@50002000,
> see arch/arm/boot/dts/stm32mp151.dtsi. The driver for
> pin-controller@50002000 is in drivers/pinctrl/stm32/pinctrl-stm32.c
> and iterates over all of its DT subnodes when registering each GPIO
> bank gpiochip. Each gpiochip has:
>
> - gpio_chip.parent = dev,
> where dev is the device node of the pin controller
> - gpio_chip.of_node = np,
> which is the OF node of the GPIO bank
>
> Therefore, dev_fwnode(chip->parent) != of_fwnode_handle(chip.of_node),
> i.e. pin-controller@50002000 != pin-controller@50002000/gpio@5000*000.
>
> The original code behaved correctly, as it extracted the "gpio-line-names"
> from of_fwnode_handle(chip.of_node) = pin-controller@50002000/gpio@5000*000.
>
> To achieve the same behaviour, read property from the firmware node.
>
> Fixes: 7cba1a4d5e162 ("gpiolib: generalize devprop_gpiochip_set_names() for device properties")
> Cc: [email protected]
> Reported-by: Marek Vasut <[email protected]>
> Reported-by: Roman Guskov <[email protected]>
> Signed-off-by: Andy Shevchenko <[email protected]>
> Tested-by: Marek Vasut <[email protected]>
> Reviewed-by: Marek Vasut <[email protected]>
> Signed-off-by: Bartosz Golaszewski <[email protected]>
> ---
> Hi Greg,
>
> This patch somehow got lost and never made its way into stable. Could you
> please apply it?
What is the git commit id of it in Linus's tree?
thanks,
greg k-h
Hi Greg,
On Sat, Apr 10, 2021 at 6:15 AM Greg Kroah-Hartman
<[email protected]> wrote:
> What is the git commit id of it in Linus's tree?
It is b41ba2ec54a70908067034f139aa23d0dd2985ce
Thanks
On Sat, Apr 10, 2021 at 11:09:19AM +0200, Bartosz Golaszewski wrote:
> From: Andy Shevchenko <[email protected]>
>
> On STM32MP1, the GPIO banks are subnodes of pin-controller@50002000,
> see arch/arm/boot/dts/stm32mp151.dtsi. The driver for
> pin-controller@50002000 is in drivers/pinctrl/stm32/pinctrl-stm32.c
> and iterates over all of its DT subnodes when registering each GPIO
> bank gpiochip. Each gpiochip has:
>
> - gpio_chip.parent = dev,
> where dev is the device node of the pin controller
> - gpio_chip.of_node = np,
> which is the OF node of the GPIO bank
>
> Therefore, dev_fwnode(chip->parent) != of_fwnode_handle(chip.of_node),
> i.e. pin-controller@50002000 != pin-controller@50002000/gpio@5000*000.
>
> The original code behaved correctly, as it extracted the "gpio-line-names"
> from of_fwnode_handle(chip.of_node) = pin-controller@50002000/gpio@5000*000.
>
> To achieve the same behaviour, read property from the firmware node.
>
> Fixes: 7cba1a4d5e162 ("gpiolib: generalize devprop_gpiochip_set_names() for device properties")
> Cc: [email protected]
> Reported-by: Marek Vasut <[email protected]>
> Reported-by: Roman Guskov <[email protected]>
> Signed-off-by: Andy Shevchenko <[email protected]>
> Tested-by: Marek Vasut <[email protected]>
> Reviewed-by: Marek Vasut <[email protected]>
> Signed-off-by: Bartosz Golaszewski <[email protected]>
> ---
> Hi Greg,
>
> This patch somehow got lost and never made its way into stable. Could you
> please apply it?
This has been added and removed more times than I can remember already.
Are you all _SURE_ this is safe for a stable kernel release? Look in
the archives for complaints when we added this in the past.
thanks,
greg k-h
On 4/10/21 2:07 PM, Greg Kroah-Hartman wrote:
> On Sat, Apr 10, 2021 at 11:09:19AM +0200, Bartosz Golaszewski wrote:
>> From: Andy Shevchenko <[email protected]>
>>
>> On STM32MP1, the GPIO banks are subnodes of pin-controller@50002000,
>> see arch/arm/boot/dts/stm32mp151.dtsi. The driver for
>> pin-controller@50002000 is in drivers/pinctrl/stm32/pinctrl-stm32.c
>> and iterates over all of its DT subnodes when registering each GPIO
>> bank gpiochip. Each gpiochip has:
>>
>> - gpio_chip.parent = dev,
>> where dev is the device node of the pin controller
>> - gpio_chip.of_node = np,
>> which is the OF node of the GPIO bank
>>
>> Therefore, dev_fwnode(chip->parent) != of_fwnode_handle(chip.of_node),
>> i.e. pin-controller@50002000 != pin-controller@50002000/gpio@5000*000.
>>
>> The original code behaved correctly, as it extracted the "gpio-line-names"
>> from of_fwnode_handle(chip.of_node) = pin-controller@50002000/gpio@5000*000.
>>
>> To achieve the same behaviour, read property from the firmware node.
>>
>> Fixes: 7cba1a4d5e162 ("gpiolib: generalize devprop_gpiochip_set_names() for device properties")
>> Cc: [email protected]
>> Reported-by: Marek Vasut <[email protected]>
>> Reported-by: Roman Guskov <[email protected]>
>> Signed-off-by: Andy Shevchenko <[email protected]>
>> Tested-by: Marek Vasut <[email protected]>
>> Reviewed-by: Marek Vasut <[email protected]>
>> Signed-off-by: Bartosz Golaszewski <[email protected]>
>> ---
>> Hi Greg,
>>
>> This patch somehow got lost and never made its way into stable. Could you
>> please apply it?
>
> This has been added and removed more times than I can remember already.
>
> Are you all _SURE_ this is safe for a stable kernel release? Look in
> the archives for complaints when we added this in the past.
I now tested this on stm32mp1, which was the original platform that got
affected by the problem this is supposed to fix, and I can confirm this
patch fixes the problem there.
So for what it's worth
Tested-by: Marek Vasut <[email protected]> # on stm32mp1
On Sat, Apr 10, 2021 at 2:07 PM Greg Kroah-Hartman
<[email protected]> wrote:
>
> On Sat, Apr 10, 2021 at 11:09:19AM +0200, Bartosz Golaszewski wrote:
> > From: Andy Shevchenko <[email protected]>
> >
> > On STM32MP1, the GPIO banks are subnodes of pin-controller@50002000,
> > see arch/arm/boot/dts/stm32mp151.dtsi. The driver for
> > pin-controller@50002000 is in drivers/pinctrl/stm32/pinctrl-stm32.c
> > and iterates over all of its DT subnodes when registering each GPIO
> > bank gpiochip. Each gpiochip has:
> >
> > - gpio_chip.parent = dev,
> > where dev is the device node of the pin controller
> > - gpio_chip.of_node = np,
> > which is the OF node of the GPIO bank
> >
> > Therefore, dev_fwnode(chip->parent) != of_fwnode_handle(chip.of_node),
> > i.e. pin-controller@50002000 != pin-controller@50002000/gpio@5000*000.
> >
> > The original code behaved correctly, as it extracted the "gpio-line-names"
> > from of_fwnode_handle(chip.of_node) = pin-controller@50002000/gpio@5000*000.
> >
> > To achieve the same behaviour, read property from the firmware node.
> >
> > Fixes: 7cba1a4d5e162 ("gpiolib: generalize devprop_gpiochip_set_names() for device properties")
> > Cc: [email protected]
> > Reported-by: Marek Vasut <[email protected]>
> > Reported-by: Roman Guskov <[email protected]>
> > Signed-off-by: Andy Shevchenko <[email protected]>
> > Tested-by: Marek Vasut <[email protected]>
> > Reviewed-by: Marek Vasut <[email protected]>
> > Signed-off-by: Bartosz Golaszewski <[email protected]>
> > ---
> > Hi Greg,
> >
> > This patch somehow got lost and never made its way into stable. Could you
> > please apply it?
>
> This has been added and removed more times than I can remember already.
>
> Are you all _SURE_ this is safe for a stable kernel release? Look in
> the archives for complaints when we added this in the past.
>
> thanks,
>
> greg k-h
IIRC it fixed the stm32mp1 problem but exposed a different problem
breaking other users until Andy fixed the deeper issue elsewhere.
It's now fine to apply it.
Bartosz