| Message ID | 20190803133436.15016-1-rfried.dev@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | gpiolib: Take MUX usage into account | expand |
sob., 3 sie 2019 o 15:34 Ramon Fried <rfried.dev@gmail.com> napisał(a): > > From: Stefan Wahren <stefan.wahren@i2se.com> > > The user space like gpioinfo only see the GPIO usage but not the > MUX usage (e.g. I2C or SPI usage) of a pin. As a user we want to know which > pin is free/safe to use. So take the MUX usage of strict pinmux controllers > into account to get a more realistic view for ioctl GPIO_GET_LINEINFO_IOCTL. > > Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> > Tested-By: Ramon Fried <rfried.dev@gmail.com> > Signed-off-by: Ramon Fried <rfried.dev@gmail.com> > --- > Sending Stefan's RFC as patch, as I tested it and it seems to work, > additionally, an accompanying fix was made by me to gpiolibd to fix a > display error of the actual result: > https://patchwork.ozlabs.org/patch/1139923/ > > drivers/gpio/gpiolib.c | 3 ++- > drivers/pinctrl/core.c | 23 +++++++++++++++++++++++ > drivers/pinctrl/pinmux.c | 18 ++++++++++++++++++ > drivers/pinctrl/pinmux.h | 7 +++++++ > include/linux/pinctrl/consumer.h | 6 ++++++ > 5 files changed, 56 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c > index e013d417a936..2fd9eee0b98c 100644 > --- a/drivers/gpio/gpiolib.c > +++ b/drivers/gpio/gpiolib.c > @@ -1082,7 +1082,8 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > test_bit(FLAG_IS_HOGGED, &desc->flags) || > test_bit(FLAG_USED_AS_IRQ, &desc->flags) || > test_bit(FLAG_EXPORT, &desc->flags) || > - test_bit(FLAG_SYSFS, &desc->flags)) > + test_bit(FLAG_SYSFS, &desc->flags) || > + pinctrl_gpio_is_in_use(chip->base + lineinfo.line_offset)) > lineinfo.flags |= GPIOLINE_FLAG_KERNEL; > if (test_bit(FLAG_IS_OUT, &desc->flags)) > lineinfo.flags |= GPIOLINE_FLAG_IS_OUT; > diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c > index a64849a9d1b0..0dd00c175eed 100644 > --- a/drivers/pinctrl/core.c > +++ b/drivers/pinctrl/core.c > @@ -759,6 +759,29 @@ int pinctrl_get_group_selector(struct pinctrl_dev *pctldev, > return -EINVAL; > } > > +bool pinctrl_gpio_is_in_use(unsigned gpio) > +{ > + struct pinctrl_dev *pctldev; > + struct pinctrl_gpio_range *range; > + bool result; > + int pin; > + > + if (pinctrl_get_device_gpio_range(gpio, &pctldev, &range)) > + return false; > + > + mutex_lock(&pctldev->mutex); > + > + /* Convert to the pin controllers number space */ > + pin = gpio_to_pin(range, gpio); > + > + result = pinmux_is_in_use(pctldev, pin); > + > + mutex_unlock(&pctldev->mutex); > + > + return result; > +} > +EXPORT_SYMBOL_GPL(pinctrl_gpio_is_in_use); > + > /** > * pinctrl_gpio_request() - request a single pin to be used as GPIO > * @gpio: the GPIO pin number from the GPIO subsystem number space > diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c > index 020e54f843f9..02d2751a4884 100644 > --- a/drivers/pinctrl/pinmux.c > +++ b/drivers/pinctrl/pinmux.c > @@ -70,6 +70,24 @@ int pinmux_validate_map(const struct pinctrl_map *map, int i) > return 0; > } > > +bool pinmux_is_in_use(struct pinctrl_dev *pctldev, unsigned pin) > +{ > + struct pin_desc *desc = pin_desc_get(pctldev, pin); > + const struct pinmux_ops *ops = pctldev->desc->pmxops; > + > + if (!desc) { > + dev_err(pctldev->dev, > + "pin %u is not registered so it cannot be requested\n", > + pin); > + return false; > + } > + > + if (ops->strict && desc->mux_usecount) > + return true; > + > + return ops->strict && !!desc->gpio_owner; > +} > + > /** > * pin_request() - request a single pin to be muxed in, typically for GPIO > * @pin: the pin number in the global pin space > diff --git a/drivers/pinctrl/pinmux.h b/drivers/pinctrl/pinmux.h > index 794cb3a003ff..24ae61136803 100644 > --- a/drivers/pinctrl/pinmux.h > +++ b/drivers/pinctrl/pinmux.h > @@ -15,6 +15,8 @@ int pinmux_check_ops(struct pinctrl_dev *pctldev); > > int pinmux_validate_map(const struct pinctrl_map *map, int i); > > +bool pinmux_is_in_use(struct pinctrl_dev *pctldev, unsigned pin); > + > int pinmux_request_gpio(struct pinctrl_dev *pctldev, > struct pinctrl_gpio_range *range, > unsigned pin, unsigned gpio); > @@ -42,6 +44,11 @@ static inline int pinmux_validate_map(const struct pinctrl_map *map, int i) > return 0; > } > > +static inline bool pinmux_is_in_use(struct pinctrl_dev *pctldev, unsigned pin) > +{ > + return false; > +} > + > static inline int pinmux_request_gpio(struct pinctrl_dev *pctldev, > struct pinctrl_gpio_range *range, > unsigned pin, unsigned gpio) > diff --git a/include/linux/pinctrl/consumer.h b/include/linux/pinctrl/consumer.h > index 86720a5a384f..d26826b057a1 100644 > --- a/include/linux/pinctrl/consumer.h > +++ b/include/linux/pinctrl/consumer.h > @@ -24,6 +24,7 @@ struct device; > #ifdef CONFIG_PINCTRL > > /* External interface to pin control */ > +extern bool pinctrl_gpio_is_in_use(unsigned gpio); > extern int pinctrl_gpio_request(unsigned gpio); > extern void pinctrl_gpio_free(unsigned gpio); > extern int pinctrl_gpio_direction_input(unsigned gpio); > @@ -61,6 +62,11 @@ static inline int pinctrl_pm_select_idle_state(struct device *dev) > > #else /* !CONFIG_PINCTRL */ > > +static inline bool pinctrl_gpio_is_in_use(unsigned gpio) > +{ > + return 0; > +} > + > static inline int pinctrl_gpio_request(unsigned gpio) > { > return 0; > -- > 2.22.0 > Looks good to me. Linus: do you see any issues with that? If not, I can pick it up. Bart
On Sat, Aug 3, 2019 at 3:34 PM Ramon Fried <rfried.dev@gmail.com> wrote: > From: Stefan Wahren <stefan.wahren@i2se.com> > > The user space like gpioinfo only see the GPIO usage but not the > MUX usage (e.g. I2C or SPI usage) of a pin. As a user we want to know which > pin is free/safe to use. So take the MUX usage of strict pinmux controllers > into account to get a more realistic view for ioctl GPIO_GET_LINEINFO_IOCTL. > > Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> > Tested-By: Ramon Fried <rfried.dev@gmail.com> > Signed-off-by: Ramon Fried <rfried.dev@gmail.com> > --- > Sending Stefan's RFC as patch, as I tested it and it seems to work, > additionally, an accompanying fix was made by me to gpiolibd to fix a > display error of the actual result: > https://patchwork.ozlabs.org/patch/1139923/ This is mostly fine, some style nits so I fixed it up when applying. Yours, Linus Walleij
On Tue, Aug 6, 2019 at 3:04 PM Linus Walleij <linus.walleij@linaro.org> wrote: > On Sat, Aug 3, 2019 at 3:34 PM Ramon Fried <rfried.dev@gmail.com> wrote: > > > From: Stefan Wahren <stefan.wahren@i2se.com> > > > > The user space like gpioinfo only see the GPIO usage but not the > > MUX usage (e.g. I2C or SPI usage) of a pin. As a user we want to know which > > pin is free/safe to use. So take the MUX usage of strict pinmux controllers > > into account to get a more realistic view for ioctl GPIO_GET_LINEINFO_IOCTL. > > > > Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> > > Tested-By: Ramon Fried <rfried.dev@gmail.com> > > Signed-off-by: Ramon Fried <rfried.dev@gmail.com> > > --- > > Sending Stefan's RFC as patch, as I tested it and it seems to work, > > additionally, an accompanying fix was made by me to gpiolibd to fix a > > display error of the actual result: > > https://patchwork.ozlabs.org/patch/1139923/ > > This is mostly fine, some style nits so I fixed it up when > applying. Ooops no. It needs a deeper rework in accordance to my comments last time it was posted. Please read this reply to Stefan's patch and address the comments: https://lore.kernel.org/linux-gpio/CACRpkdb5DjAMRYkT+b0U6HVk7E6ccLT79-LB=QGQWWtE17aPUg@mail.gmail.com/ Yours, Linus Walleij
On August 6, 2019 4:11:27 PM GMT+03:00, Linus Walleij <linus.walleij@linaro.org> wrote: >On Tue, Aug 6, 2019 at 3:04 PM Linus Walleij <linus.walleij@linaro.org> >wrote: >> On Sat, Aug 3, 2019 at 3:34 PM Ramon Fried <rfried.dev@gmail.com> >wrote: >> >> > From: Stefan Wahren <stefan.wahren@i2se.com> >> > >> > The user space like gpioinfo only see the GPIO usage but not the >> > MUX usage (e.g. I2C or SPI usage) of a pin. As a user we want to >know which >> > pin is free/safe to use. So take the MUX usage of strict pinmux >controllers >> > into account to get a more realistic view for ioctl >GPIO_GET_LINEINFO_IOCTL. >> > >> > Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> >> > Tested-By: Ramon Fried <rfried.dev@gmail.com> >> > Signed-off-by: Ramon Fried <rfried.dev@gmail.com> >> > --- >> > Sending Stefan's RFC as patch, as I tested it and it seems to work, >> > additionally, an accompanying fix was made by me to gpiolibd to fix >a >> > display error of the actual result: >> > https://patchwork.ozlabs.org/patch/1139923/ >> >> This is mostly fine, some style nits so I fixed it up when >> applying. > >Ooops no. It needs a deeper rework in accordance to my comments >last time it was posted. Please read this reply to Stefan's patch >and address the comments: > NP, I'll try to address these in a new patch. Thanks. Ramon >https://lore.kernel.org/linux-gpio/CACRpkdb5DjAMRYkT+b0U6HVk7E6ccLT79-LB=QGQWWtE17aPUg@mail.gmail.com/ > >Yours, >Linus Walleij
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index e013d417a936..2fd9eee0b98c 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1082,7 +1082,8 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) test_bit(FLAG_IS_HOGGED, &desc->flags) || test_bit(FLAG_USED_AS_IRQ, &desc->flags) || test_bit(FLAG_EXPORT, &desc->flags) || - test_bit(FLAG_SYSFS, &desc->flags)) + test_bit(FLAG_SYSFS, &desc->flags) || + pinctrl_gpio_is_in_use(chip->base + lineinfo.line_offset)) lineinfo.flags |= GPIOLINE_FLAG_KERNEL; if (test_bit(FLAG_IS_OUT, &desc->flags)) lineinfo.flags |= GPIOLINE_FLAG_IS_OUT; diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index a64849a9d1b0..0dd00c175eed 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -759,6 +759,29 @@ int pinctrl_get_group_selector(struct pinctrl_dev *pctldev, return -EINVAL; } +bool pinctrl_gpio_is_in_use(unsigned gpio) +{ + struct pinctrl_dev *pctldev; + struct pinctrl_gpio_range *range; + bool result; + int pin; + + if (pinctrl_get_device_gpio_range(gpio, &pctldev, &range)) + return false; + + mutex_lock(&pctldev->mutex); + + /* Convert to the pin controllers number space */ + pin = gpio_to_pin(range, gpio); + + result = pinmux_is_in_use(pctldev, pin); + + mutex_unlock(&pctldev->mutex); + + return result; +} +EXPORT_SYMBOL_GPL(pinctrl_gpio_is_in_use); + /** * pinctrl_gpio_request() - request a single pin to be used as GPIO * @gpio: the GPIO pin number from the GPIO subsystem number space diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c index 020e54f843f9..02d2751a4884 100644 --- a/drivers/pinctrl/pinmux.c +++ b/drivers/pinctrl/pinmux.c @@ -70,6 +70,24 @@ int pinmux_validate_map(const struct pinctrl_map *map, int i) return 0; } +bool pinmux_is_in_use(struct pinctrl_dev *pctldev, unsigned pin) +{ + struct pin_desc *desc = pin_desc_get(pctldev, pin); + const struct pinmux_ops *ops = pctldev->desc->pmxops; + + if (!desc) { + dev_err(pctldev->dev, + "pin %u is not registered so it cannot be requested\n", + pin); + return false; + } + + if (ops->strict && desc->mux_usecount) + return true; + + return ops->strict && !!desc->gpio_owner; +} + /** * pin_request() - request a single pin to be muxed in, typically for GPIO * @pin: the pin number in the global pin space diff --git a/drivers/pinctrl/pinmux.h b/drivers/pinctrl/pinmux.h index 794cb3a003ff..24ae61136803 100644 --- a/drivers/pinctrl/pinmux.h +++ b/drivers/pinctrl/pinmux.h @@ -15,6 +15,8 @@ int pinmux_check_ops(struct pinctrl_dev *pctldev); int pinmux_validate_map(const struct pinctrl_map *map, int i); +bool pinmux_is_in_use(struct pinctrl_dev *pctldev, unsigned pin); + int pinmux_request_gpio(struct pinctrl_dev *pctldev, struct pinctrl_gpio_range *range, unsigned pin, unsigned gpio); @@ -42,6 +44,11 @@ static inline int pinmux_validate_map(const struct pinctrl_map *map, int i) return 0; } +static inline bool pinmux_is_in_use(struct pinctrl_dev *pctldev, unsigned pin) +{ + return false; +} + static inline int pinmux_request_gpio(struct pinctrl_dev *pctldev, struct pinctrl_gpio_range *range, unsigned pin, unsigned gpio) diff --git a/include/linux/pinctrl/consumer.h b/include/linux/pinctrl/consumer.h index 86720a5a384f..d26826b057a1 100644 --- a/include/linux/pinctrl/consumer.h +++ b/include/linux/pinctrl/consumer.h @@ -24,6 +24,7 @@ struct device; #ifdef CONFIG_PINCTRL /* External interface to pin control */ +extern bool pinctrl_gpio_is_in_use(unsigned gpio); extern int pinctrl_gpio_request(unsigned gpio); extern void pinctrl_gpio_free(unsigned gpio); extern int pinctrl_gpio_direction_input(unsigned gpio); @@ -61,6 +62,11 @@ static inline int pinctrl_pm_select_idle_state(struct device *dev) #else /* !CONFIG_PINCTRL */ +static inline bool pinctrl_gpio_is_in_use(unsigned gpio) +{ + return 0; +} + static inline int pinctrl_gpio_request(unsigned gpio) { return 0;