On 10/9/23 9:34 AM, Dipen Patel wrote: > On 10/8/23 11:48 PM, Bartosz Golaszewski wrote: >> On Thu, Oct 5, 2023 at 9:43 PM Dipen Patel <dipenp@xxxxxxxxxx> wrote: >>> >>> On 10/5/23 12:05 PM, Bartosz Golaszewski wrote: >>>> 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). >>> What do you suggest I should use for the match as I do not see chip->fwnode >>> being set? >>> >> >> This is most likely going to be a longer discussion. I suggest that in >> the meantime you just assign the gc->fwnode pointer explicitly from >> the platform device in the tegra GPIO driver and use it in the lookup >> function. Note that this is NOT wrong or a hack. It's just that most >> devices don't need to be looked up using gpio_device_find(). > > Sure, at the same time, I am also find to use any other method/s. (Correction) I am also fine* With patch https://patchwork.ozlabs.org/project/linux-gpio/patch/20231009173858.723686-1-dipenp@xxxxxxxxxx/ Tested-by: Dipen Patel <dipenp@xxxxxxxxxx> >> >> Bart >> >>>> >>>> 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 >>>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>> >>>>> >>> >
