| Message ID | 20220903-gpiod_get_from_of_node-remove-v1-4-b29adfb27a6c@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | Get rid of [devm_]gpiod_get_from_of_node() public APIs | expand |
On Mon, Sep 5, 2022 at 9:32 AM Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote: > > I would like to stop exporting OF-specific devm_gpiod_get_from_of_node() > so that gpiolib can be cleaned a bit, so let's switch to the generic > device property API. > > I believe that the only reason the driver, instead of the standard > devm_gpiod_get(), used devm_gpiod_get_from_of_node() is because it > wanted to set up a pretty consumer name for the GPIO, and we now have > a special API for that. ... > - gpiod = devm_gpiod_get_from_of_node(&pdev->dev, np, > - "nvidia,phy-reset-gpio", > - 0, GPIOD_OUT_HIGH, > - "ulpi_phy_reset_b"); > + gpiod = devm_gpiod_get(&pdev->dev, "nvidia,phy-reset", > + GPIOD_OUT_HIGH); > err = PTR_ERR_OR_ZERO(gpiod); What does _OR_ZERO mean now? > if (err) { > dev_err(&pdev->dev, > "Request failed for reset GPIO: %d\n", err); > return err; > }
On Mon, Sep 05, 2022 at 01:59:44PM +0300, Andy Shevchenko wrote: > On Mon, Sep 5, 2022 at 9:32 AM Dmitry Torokhov > <dmitry.torokhov@gmail.com> wrote: > > > > I would like to stop exporting OF-specific devm_gpiod_get_from_of_node() > > so that gpiolib can be cleaned a bit, so let's switch to the generic > > device property API. > > > > I believe that the only reason the driver, instead of the standard > > devm_gpiod_get(), used devm_gpiod_get_from_of_node() is because it > > wanted to set up a pretty consumer name for the GPIO, and we now have > > a special API for that. > > ... > > > - gpiod = devm_gpiod_get_from_of_node(&pdev->dev, np, > > - "nvidia,phy-reset-gpio", > > - 0, GPIOD_OUT_HIGH, > > - "ulpi_phy_reset_b"); > > + gpiod = devm_gpiod_get(&pdev->dev, "nvidia,phy-reset", > > + GPIOD_OUT_HIGH); > > err = PTR_ERR_OR_ZERO(gpiod); > > What does _OR_ZERO mean now? This converts a pointer to an error code if a pointer represents ERR_PTR() encoded error, or 0 to indicate success. static inline int __must_check PTR_ERR_OR_ZERO(__force const void *ptr) { if (IS_ERR(ptr)) return PTR_ERR(ptr); else return 0; } Thanks.
On Mon, Sep 5, 2022 at 10:40 PM Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote: > On Mon, Sep 05, 2022 at 01:59:44PM +0300, Andy Shevchenko wrote: > > On Mon, Sep 5, 2022 at 9:32 AM Dmitry Torokhov > > <dmitry.torokhov@gmail.com> wrote: ... > > > - gpiod = devm_gpiod_get_from_of_node(&pdev->dev, np, > > > - "nvidia,phy-reset-gpio", > > > - 0, GPIOD_OUT_HIGH, > > > - "ulpi_phy_reset_b"); > > > + gpiod = devm_gpiod_get(&pdev->dev, "nvidia,phy-reset", > > > + GPIOD_OUT_HIGH); > > > err = PTR_ERR_OR_ZERO(gpiod); > > > > What does _OR_ZERO mean now? > > This converts a pointer to an error code if a pointer represents > ERR_PTR() encoded error, or 0 to indicate success. Yes, I know that. My point is, how is it useful now (or even before)? I mean that devm_gpio_get() never returns NULL, right?
On Mon, Sep 05, 2022 at 10:41:40PM +0300, Andy Shevchenko wrote: > On Mon, Sep 5, 2022 at 10:40 PM Dmitry Torokhov > <dmitry.torokhov@gmail.com> wrote: > > On Mon, Sep 05, 2022 at 01:59:44PM +0300, Andy Shevchenko wrote: > > > On Mon, Sep 5, 2022 at 9:32 AM Dmitry Torokhov > > > <dmitry.torokhov@gmail.com> wrote: > > ... > > > > > - gpiod = devm_gpiod_get_from_of_node(&pdev->dev, np, > > > > - "nvidia,phy-reset-gpio", > > > > - 0, GPIOD_OUT_HIGH, > > > > - "ulpi_phy_reset_b"); > > > > + gpiod = devm_gpiod_get(&pdev->dev, "nvidia,phy-reset", > > > > + GPIOD_OUT_HIGH); > > > > err = PTR_ERR_OR_ZERO(gpiod); > > > > > > What does _OR_ZERO mean now? > > > > This converts a pointer to an error code if a pointer represents > > ERR_PTR() encoded error, or 0 to indicate success. > > Yes, I know that. My point is, how is it useful now (or even before)? > I mean that devm_gpio_get() never returns NULL, right? What does returning NULL have to do with anything. It converts a pointer to a "classic" return code, with negative errors and 0 on success. It allows to not use multiple IS_ERR/PTR_ERR in the code (I'd need 1 IS_ERR and 2 PTR_ERR, one in dev_err() and another to return). Thanks.
On Mon, Sep 5, 2022 at 10:51 PM Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote: > On Mon, Sep 05, 2022 at 10:41:40PM +0300, Andy Shevchenko wrote: > > On Mon, Sep 5, 2022 at 10:40 PM Dmitry Torokhov > > <dmitry.torokhov@gmail.com> wrote: > > > On Mon, Sep 05, 2022 at 01:59:44PM +0300, Andy Shevchenko wrote: > > > > On Mon, Sep 5, 2022 at 9:32 AM Dmitry Torokhov > > > > <dmitry.torokhov@gmail.com> wrote: ... > > > > > - gpiod = devm_gpiod_get_from_of_node(&pdev->dev, np, > > > > > - "nvidia,phy-reset-gpio", > > > > > - 0, GPIOD_OUT_HIGH, > > > > > - "ulpi_phy_reset_b"); > > > > > + gpiod = devm_gpiod_get(&pdev->dev, "nvidia,phy-reset", > > > > > + GPIOD_OUT_HIGH); > > > > > err = PTR_ERR_OR_ZERO(gpiod); > > > > > > > > What does _OR_ZERO mean now? > > > > > > This converts a pointer to an error code if a pointer represents > > > ERR_PTR() encoded error, or 0 to indicate success. > > > > Yes, I know that. My point is, how is it useful now (or even before)? > > I mean that devm_gpio_get() never returns NULL, right? > > What does returning NULL have to do with anything. It has to do with a dead code. If defm_gpiod_get() does not return NULL, then why do we even bother to check? > It converts a pointer > to a "classic" return code, with negative errors and 0 on success. > > It allows to not use multiple IS_ERR/PTR_ERR in the code (I'd need 1 > IS_ERR and 2 PTR_ERR, one in dev_err() and another to return). I don't see how this is relevant.
On 9/5/22 12:55, Andy Shevchenko wrote: > On Mon, Sep 5, 2022 at 10:51 PM Dmitry Torokhov > <dmitry.torokhov@gmail.com> wrote: >> On Mon, Sep 05, 2022 at 10:41:40PM +0300, Andy Shevchenko wrote: >>> On Mon, Sep 5, 2022 at 10:40 PM Dmitry Torokhov >>> <dmitry.torokhov@gmail.com> wrote: >>>> On Mon, Sep 05, 2022 at 01:59:44PM +0300, Andy Shevchenko wrote: >>>>> On Mon, Sep 5, 2022 at 9:32 AM Dmitry Torokhov >>>>> <dmitry.torokhov@gmail.com> wrote: > > ... > >>>>>> - gpiod = devm_gpiod_get_from_of_node(&pdev->dev, np, >>>>>> - "nvidia,phy-reset-gpio", >>>>>> - 0, GPIOD_OUT_HIGH, >>>>>> - "ulpi_phy_reset_b"); >>>>>> + gpiod = devm_gpiod_get(&pdev->dev, "nvidia,phy-reset", >>>>>> + GPIOD_OUT_HIGH); >>>>>> err = PTR_ERR_OR_ZERO(gpiod); >>>>> >>>>> What does _OR_ZERO mean now? >>>> >>>> This converts a pointer to an error code if a pointer represents >>>> ERR_PTR() encoded error, or 0 to indicate success. >>> >>> Yes, I know that. My point is, how is it useful now (or even before)? >>> I mean that devm_gpio_get() never returns NULL, right? >> >> What does returning NULL have to do with anything. > > It has to do with a dead code. If defm_gpiod_get() does not return > NULL, then why do we even bother to check? > PTR_ERR_OR_ZERO() converts into an error code (if the pointer is an ERR_PTR) or 0 if it is a real pointer. Its purpose is not to convert NULL into 0, its purpose is to convert a pointer either into an error code or 0. That is what is done here, and it is done all over the place in the kernel. I don't see your problem with it. Care to explain ? >> It converts a pointer >> to a "classic" return code, with negative errors and 0 on success. >> >> It allows to not use multiple IS_ERR/PTR_ERR in the code (I'd need 1 >> IS_ERR and 2 PTR_ERR, one in dev_err() and another to return). > > I don't see how this is relevant. > You lost me. Really, please explain your problem with PTR_ERR_OR_ZERO(). Thanks, Guenter
On Mon, Sep 05, 2022 at 03:07:48PM -0700, Guenter Roeck wrote: > On 9/5/22 12:55, Andy Shevchenko wrote: > > On Mon, Sep 5, 2022 at 10:51 PM Dmitry Torokhov > > <dmitry.torokhov@gmail.com> wrote: > > > On Mon, Sep 05, 2022 at 10:41:40PM +0300, Andy Shevchenko wrote: > > > > On Mon, Sep 5, 2022 at 10:40 PM Dmitry Torokhov > > > > <dmitry.torokhov@gmail.com> wrote: > > > > > On Mon, Sep 05, 2022 at 01:59:44PM +0300, Andy Shevchenko wrote: > > > > > > On Mon, Sep 5, 2022 at 9:32 AM Dmitry Torokhov > > > > > > <dmitry.torokhov@gmail.com> wrote: ... > > > > > > > + gpiod = devm_gpiod_get(&pdev->dev, "nvidia,phy-reset", > > > > > > > + GPIOD_OUT_HIGH); > > > > > > > err = PTR_ERR_OR_ZERO(gpiod); > > > > > > > > > > > > What does _OR_ZERO mean now? > > > > > > > > > > This converts a pointer to an error code if a pointer represents > > > > > ERR_PTR() encoded error, or 0 to indicate success. > > > > > > > > Yes, I know that. My point is, how is it useful now (or even before)? > > > > I mean that devm_gpio_get() never returns NULL, right? > > > > > > What does returning NULL have to do with anything. > > > > It has to do with a dead code. If defm_gpiod_get() does not return > > NULL, then why do we even bother to check? > > PTR_ERR_OR_ZERO() converts into an error code (if the pointer is an > ERR_PTR) or 0 if it is a real pointer. Its purpose is not to convert > NULL into 0, its purpose is to convert a pointer either into an error > code or 0. That is what is done here, and it is done all over the place > in the kernel. I don't see your problem with it. Care to explain ? > > > > It converts a pointer > > > to a "classic" return code, with negative errors and 0 on success. > > > > > > It allows to not use multiple IS_ERR/PTR_ERR in the code (I'd need 1 > > > IS_ERR and 2 PTR_ERR, one in dev_err() and another to return). > > > > I don't see how this is relevant. > > You lost me. Really, please explain your problem with PTR_ERR_OR_ZERO(). I don't know what I was thinking about... You, guys, are right, sorry for my noise.
diff --git a/drivers/usb/phy/phy-tegra-usb.c b/drivers/usb/phy/phy-tegra-usb.c index 68cd4b68e3a2..f0240107edb1 100644 --- a/drivers/usb/phy/phy-tegra-usb.c +++ b/drivers/usb/phy/phy-tegra-usb.c @@ -1440,16 +1440,22 @@ static int tegra_usb_phy_probe(struct platform_device *pdev) return err; } - gpiod = devm_gpiod_get_from_of_node(&pdev->dev, np, - "nvidia,phy-reset-gpio", - 0, GPIOD_OUT_HIGH, - "ulpi_phy_reset_b"); + gpiod = devm_gpiod_get(&pdev->dev, "nvidia,phy-reset", + GPIOD_OUT_HIGH); err = PTR_ERR_OR_ZERO(gpiod); if (err) { dev_err(&pdev->dev, "Request failed for reset GPIO: %d\n", err); return err; } + + err = gpiod_set_consumer_name(gpiod, "ulpi_phy_reset_b"); + if (err) { + dev_err(&pdev->dev, + "Failed to set up reset GPIO name: %d\n", err); + return err; + } + tegra_phy->reset_gpio = gpiod; phy = devm_otg_ulpi_create(&pdev->dev,
I would like to stop exporting OF-specific devm_gpiod_get_from_of_node() so that gpiolib can be cleaned a bit, so let's switch to the generic device property API. I believe that the only reason the driver, instead of the standard devm_gpiod_get(), used devm_gpiod_get_from_of_node() is because it wanted to set up a pretty consumer name for the GPIO, and we now have a special API for that. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>