Message ID | 20210410090919.3157-1-brgl@bgdev.pl |
---|---|
State | New |
Headers | show |
Series | [stable] gpiolib: Read "gpio-line-names" from a firmware node | expand |
On Sat, Apr 10, 2021 at 11:09:19AM +0200, Bartosz Golaszewski wrote: > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > 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: stable@vger.kernel.org > Reported-by: Marek Vasut <marex@denx.de> > Reported-by: Roman Guskov <rguskov@dh-electronics.com> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Tested-by: Marek Vasut <marex@denx.de> > Reviewed-by: Marek Vasut <marex@denx.de> > Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> > --- > 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
<gregkh@linuxfoundation.org> 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 <andriy.shevchenko@linux.intel.com> > > 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: stable@vger.kernel.org > Reported-by: Marek Vasut <marex@denx.de> > Reported-by: Roman Guskov <rguskov@dh-electronics.com> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Tested-by: Marek Vasut <marex@denx.de> > Reviewed-by: Marek Vasut <marex@denx.de> > Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> > --- > 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 <andriy.shevchenko@linux.intel.com> >> >> 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: stable@vger.kernel.org >> Reported-by: Marek Vasut <marex@denx.de> >> Reported-by: Roman Guskov <rguskov@dh-electronics.com> >> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> >> Tested-by: Marek Vasut <marex@denx.de> >> Reviewed-by: Marek Vasut <marex@denx.de> >> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> >> --- >> 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 <marex@denx.de> # on stm32mp1
On Sat, Apr 10, 2021 at 2:07 PM Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote: > > On Sat, Apr 10, 2021 at 11:09:19AM +0200, Bartosz Golaszewski wrote: > > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > > > 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: stable@vger.kernel.org > > Reported-by: Marek Vasut <marex@denx.de> > > Reported-by: Roman Guskov <rguskov@dh-electronics.com> > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > Tested-by: Marek Vasut <marex@denx.de> > > Reviewed-by: Marek Vasut <marex@denx.de> > > Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> > > --- > > 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
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");