On Thu, Oct 5, 2023 at 8:12 PM Dipen Patel <dipenp@xxxxxxxxxx> wrote: > > On 10/5/23 6:48 AM, Bartosz Golaszewski wrote: > > On Thu, Oct 5, 2023 at 1:52 AM Dipen Patel <dipenp@xxxxxxxxxx> wrote: > >> > >> On 10/4/23 3:54 PM, Dipen Patel wrote: > >>> On 10/4/23 1:33 PM, Dipen Patel wrote: > >>>> On 10/4/23 1:30 PM, Dipen Patel wrote: > >>>>> On 10/4/23 5:00 AM, Bartosz Golaszewski wrote: > >>>>>> On Thu, Sep 7, 2023 at 9:28 AM Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: > >>>>>>> > >>>>>>> On Tue, Sep 5, 2023 at 8:53 PM Bartosz Golaszewski <brgl@xxxxxxxx> wrote: > >>>>>>> > >>>>>>>> From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> > >>>>>>>> > >>>>>>>> Using struct gpio_chip is not safe as it will disappear if the > >>>>>>>> underlying driver is unbound for any reason. Switch to using reference > >>>>>>>> counted struct gpio_device and its dedicated accessors. > >>>>>>>> > >>>>>>>> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> > >>>>>>> > >>>>>>> As Andy points out add <linux/cleanup.h>, with that fixed: > >>>>>>> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> > >>>>>>> > >>>>>>> I think this can be merged into the gpio tree after leaving some > >>>>>>> slack for the HTE maintainer to look at it, things look so much > >>>>>>> better after this. > >>>>>>> > >>>>>>> Yours, > >>>>>>> Linus Walleij > >>>>>> > >>>>>> Dipen, > >>>>>> > >>>>>> if you could give this patch a test and possibly ack it for me to take > >>>>>> it through the GPIO tree (or go the immutable tag from HTE route) then > >>>>>> it would be great. This is the last user of gpiochip_find() treewide, > >>>>>> so with it we could remove it entirely for v6.7. > >>>>> > >>>>> Progress so far for the RFT... > >>>>> > >>>>> I tried applying the patch series on 6.6-rc1 and it did not apply cleanly, > >>>>> some patches I needed to manually apply and correct. With all this, it failed > >>>>> compilation at some spi/spi-bcm2835 driver. I disabled that and was able to > >>>>> compile. I thought I should let you know this part. > >>>>> > >>>>> Now, I tried to test the hte and it seems to fail finding the gpio device, > >>>>> roughly around this place [1]. I thought it would be your patch series so > >>>>> tried to just use 6.6rc1 without your patches and it still failed at the > >>>>> same place. I have to trace back now from which kernel version it broke. > >>>> > >>>> [1]. > >>>> https://git.kernel.org/pub/scm/linux/kernel/git/pateldipen1984/linux.git/tree/drivers/hte/hte-tegra194.c?h=for-next#n781 > >>>> > >>>> of course with your patches it would fail for the gdev instead of the chip. > >>> > >>> Small update: > >>> > >>> I put some debugging prints in the gpio match function in the hte-tegra194.c as > >>> below: > >>> > >>> static int tegra_gpiochip_match(struct gpio_chip *chip, void *data) > >>> { > >>> + struct device_node *node = data; > >>> + struct fwnode_handle *fw = of_node_to_fwnode(data); > >>> + if (!fw || !chip->fwnode) > >>> + pr_err("dipen patel: fw is null\n"); > >>> > >>> - pr_err("%s:%d\n", __func__, __LINE__); > >>> + pr_err("dipen patel, %s:%d: %s, %s, %s, match?:%d, fwnode name:%s\n", > >>> __func__, __LINE__, chip->label, node->name, node->full_name, (chip->fwnode == > >>> fw), fw->dev->init_name); > >>> return chip->fwnode == of_node_to_fwnode(data); > >>> } > >>> > >>> The output of the printfs looks like below: > >>> [ 3.955194] dipen patel: fw is null -----> this message started appearing > >>> when I added !chip->fwnode test in the if condition line. > >>> > >>> [ 3.958864] dipen patel, tegra_gpiochip_match:689: tegra234-gpio, gpio, > >>> gpio@c2f0000, match?:0, fwnode name:(null) > >>> > >>> I conclude that chip->fwnode is empty. Any idea in which conditions that node > >>> would be empty? > >> > >> sorry for spamming, one last message before I sign off for the day.... > >> > >> Seems, adding below in the tegra gpio driver resolved the issue I am facing, I > >> was able to verify your patch series. > >> > >> diff --git a/drivers/gpio/gpio-tegra186.c b/drivers/gpio/gpio-tegra186.c > >> index d87dd06db40d..a56c159d7136 100644 > >> --- a/drivers/gpio/gpio-tegra186.c > >> +++ b/drivers/gpio/gpio-tegra186.c > >> @@ -989,6 +989,8 @@ static int tegra186_gpio_probe(struct platform_device *pdev) > >> offset += port->pins; > >> } > >> > >> + gpio->gpio.fwnode = of_node_to_fwnode(pdev->dev.of_node); > >> + > >> return devm_gpiochip_add_data(&pdev->dev, &gpio->gpio, gpio); > >> } > >> > >> Now, few follow up questions: > >> 1) is this the correct way of setting the chip fwnode in the gpio driver? > > > > You shouldn't need this. This driver already does: > > > > gpio->gpio.parent = &pdev->dev; > > > > so fwnode should be assigned in gpiochip_add_data_with_key(). Can you > > check why this doesn't happen? > > I do not see anywhere chip->fwnode being set in the gpiochip_add_* function. > The only reference I see is here [1]. Does it mean I need to change my match > function from: > > chip->fwnode == of_node_to_fwnode(data) > > to: > dev_fwnode(chip->parent) == of_node_to_fwnode(data)? No! chip->fwnode is only used to let GPIOLIB know which fwnode to assign to the GPIO device (struct gpio_device). Bart > > [1]: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpio/gpiolib.c?h=v6.6-rc1#n767 > > > > > Bart > > > >> 2) Or should I use something else in hte matching function instead of fwnode so > >> to avoid adding above line in the gpio driver? > >> > >>> > >>>>> > >>>>>> > >>>>>> Bart > >>>>> > >>>> > >>> > >> >
