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)? [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 >>>>> >>>> >>> >>
