From: Stefan Wahren <[email protected]>
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 <[email protected]>
Tested-By: Ramon Fried <[email protected]>
Signed-off-by: Ramon Fried <[email protected]>
---
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
sob., 3 sie 2019 o 15:34 Ramon Fried <[email protected]> napisał(a):
>
> From: Stefan Wahren <[email protected]>
>
> 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 <[email protected]>
> Tested-By: Ramon Fried <[email protected]>
> Signed-off-by: Ramon Fried <[email protected]>
> ---
> 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 <[email protected]> wrote:
> From: Stefan Wahren <[email protected]>
>
> 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 <[email protected]>
> Tested-By: Ramon Fried <[email protected]>
> Signed-off-by: Ramon Fried <[email protected]>
> ---
> 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 <[email protected]> wrote:
> On Sat, Aug 3, 2019 at 3:34 PM Ramon Fried <[email protected]> wrote:
>
> > From: Stefan Wahren <[email protected]>
> >
> > 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 <[email protected]>
> > Tested-By: Ramon Fried <[email protected]>
> > Signed-off-by: Ramon Fried <[email protected]>
> > ---
> > 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 <[email protected]> wrote:
>On Tue, Aug 6, 2019 at 3:04 PM Linus Walleij <[email protected]>
>wrote:
>> On Sat, Aug 3, 2019 at 3:34 PM Ramon Fried <[email protected]>
>wrote:
>>
>> > From: Stefan Wahren <[email protected]>
>> >
>> > 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 <[email protected]>
>> > Tested-By: Ramon Fried <[email protected]>
>> > Signed-off-by: Ramon Fried <[email protected]>
>> > ---
>> > 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
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.