[PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour

Marcos Del Sol Vives posted 3 patches 1 month, 1 week ago
There is a newer version of this series
[PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
Posted by Marcos Del Sol Vives 1 month, 1 week ago
The Vortex86 family of SoCs need the direction set before the value, else
writes to the DATA ports are ignored.

This commit adds a new "flags" field plus a flag to change the default
behaviour, which is to set first the direction and then the value.

Signed-off-by: Marcos Del Sol Vives <marcos@orca.pet>
---
 drivers/gpio/gpio-regmap.c  | 17 ++++++++++++++++-
 include/linux/gpio/regmap.h | 17 +++++++++++++++++
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
index e8a32dfebdcb..24cefbd57637 100644
--- a/drivers/gpio/gpio-regmap.c
+++ b/drivers/gpio/gpio-regmap.c
@@ -31,6 +31,7 @@ struct gpio_regmap {
 	unsigned int reg_clr_base;
 	unsigned int reg_dir_in_base;
 	unsigned int reg_dir_out_base;
+	unsigned int flags;
 
 	int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
 			      unsigned int offset, unsigned int *reg,
@@ -196,7 +197,20 @@ static int gpio_regmap_direction_input(struct gpio_chip *chip,
 static int gpio_regmap_direction_output(struct gpio_chip *chip,
 					unsigned int offset, int value)
 {
-	gpio_regmap_set(chip, offset, value);
+	struct gpio_regmap *gpio = gpiochip_get_data(chip);
+	int ret;
+
+	if (gpio->flags & GPIO_REGMAP_DIR_BEFORE_SET) {
+		ret = gpio_regmap_set_direction(chip, offset, true);
+		if (ret)
+			return ret;
+
+		return gpio_regmap_set(chip, offset, value);
+	}
+
+	ret = gpio_regmap_set(chip, offset, value);
+	if (ret)
+		return ret;
 
 	return gpio_regmap_set_direction(chip, offset, true);
 }
@@ -247,6 +261,7 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
 	gpio->reg_clr_base = config->reg_clr_base;
 	gpio->reg_dir_in_base = config->reg_dir_in_base;
 	gpio->reg_dir_out_base = config->reg_dir_out_base;
+	gpio->flags = config->flags;
 
 	chip = &gpio->gpio_chip;
 	chip->parent = config->parent;
diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h
index c722c67668c6..aea107e71fec 100644
--- a/include/linux/gpio/regmap.h
+++ b/include/linux/gpio/regmap.h
@@ -12,6 +12,20 @@ struct regmap;
 #define GPIO_REGMAP_ADDR_ZERO ((unsigned int)(-1))
 #define GPIO_REGMAP_ADDR(addr) ((addr) ? : GPIO_REGMAP_ADDR_ZERO)
 
+
+/**
+ * enum gpio_regmap_flags - flags to control GPIO operation
+ */
+enum gpio_regmap_flags {
+	/**
+	 * @GPIO_REGMAP_DIR_BEFORE_SET: when setting a pin as an output, set
+	 * its direction before the value. The output value will be undefined
+	 * for a short time which may have unwanted side effects, but some
+	 * hardware requires this.
+	 */
+	GPIO_REGMAP_DIR_BEFORE_SET	= BIT(0),
+};
+
 /**
  * struct gpio_regmap_config - Description of a generic regmap gpio_chip.
  * @parent:		The parent device
@@ -23,6 +37,8 @@ struct regmap;
  *			If not given, the name of the device is used.
  * @ngpio:		(Optional) Number of GPIOs
  * @names:		(Optional) Array of names for gpios
+ * @flags:		(Optional) A bitmask of flags from
+ * 			&enum gpio_regmap_flags
  * @reg_dat_base:	(Optional) (in) register base address
  * @reg_set_base:	(Optional) set register base address
  * @reg_clr_base:	(Optional) clear register base address
@@ -68,6 +84,7 @@ struct gpio_regmap_config {
 	const char *label;
 	int ngpio;
 	const char *const *names;
+	unsigned int flags;
 
 	unsigned int reg_dat_base;
 	unsigned int reg_set_base;
-- 
2.34.1
Re: [PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
Posted by kernel test robot 1 month, 1 week ago
Hi Marcos,

kernel test robot noticed the following build errors:

[auto build test ERROR on brgl/gpio/for-next]
[also build test ERROR on lee-mfd/for-mfd-next lee-mfd/for-mfd-fixes pci/next pci/for-linus linus/master v6.17-rc2 next-20250821]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Marcos-Del-Sol-Vives/gpio-gpio-regmap-add-flags-to-control-some-behaviour/20250821-182416
base:   https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git gpio/for-next
patch link:    https://lore.kernel.org/r/20250821101902.626329-2-marcos%40orca.pet
patch subject: [PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
config: x86_64-buildonly-randconfig-001-20250822 (https://download.01.org/0day-ci/archive/20250822/202508221142.ETxcEpjA-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250822/202508221142.ETxcEpjA-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202508221142.ETxcEpjA-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from drivers/gpio/gpio-fxl6408.c:11:
>> include/linux/gpio/regmap.h:26:31: error: call to undeclared function 'BIT'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
      26 |         GPIO_REGMAP_DIR_BEFORE_SET      = BIT(0),
         |                                           ^
>> include/linux/gpio/regmap.h:26:31: error: expression is not an integer constant expression
      26 |         GPIO_REGMAP_DIR_BEFORE_SET      = BIT(0),
         |                                           ^~~~~~
   In file included from drivers/gpio/gpio-fxl6408.c:12:
   In file included from include/linux/i2c.h:13:
   In file included from include/linux/acpi.h:14:
   In file included from include/linux/device.h:32:
   In file included from include/linux/device/driver.h:21:
   In file included from include/linux/module.h:20:
   In file included from include/linux/elf.h:6:
   In file included from arch/x86/include/asm/elf.h:10:
   In file included from arch/x86/include/asm/ia32.h:7:
   In file included from include/linux/compat.h:17:
   In file included from include/linux/fs.h:34:
   In file included from include/linux/percpu-rwsem.h:7:
   In file included from include/linux/rcuwait.h:6:
   In file included from include/linux/sched/signal.h:6:
   include/linux/signal.h:98:11: warning: array index 3 is past the end of the array (that has type 'unsigned long[1]') [-Warray-bounds]
      98 |                 return (set->sig[3] | set->sig[2] |
         |                         ^        ~
   arch/x86/include/asm/signal.h:24:2: note: array 'sig' declared here
      24 |         unsigned long sig[_NSIG_WORDS];
         |         ^
   In file included from drivers/gpio/gpio-fxl6408.c:12:
   In file included from include/linux/i2c.h:13:
   In file included from include/linux/acpi.h:14:
   In file included from include/linux/device.h:32:
   In file included from include/linux/device/driver.h:21:
   In file included from include/linux/module.h:20:
   In file included from include/linux/elf.h:6:
   In file included from arch/x86/include/asm/elf.h:10:
   In file included from arch/x86/include/asm/ia32.h:7:
   In file included from include/linux/compat.h:17:
   In file included from include/linux/fs.h:34:
   In file included from include/linux/percpu-rwsem.h:7:
   In file included from include/linux/rcuwait.h:6:
   In file included from include/linux/sched/signal.h:6:
   include/linux/signal.h:98:25: warning: array index 2 is past the end of the array (that has type 'unsigned long[1]') [-Warray-bounds]
      98 |                 return (set->sig[3] | set->sig[2] |
         |                                       ^        ~
   arch/x86/include/asm/signal.h:24:2: note: array 'sig' declared here
      24 |         unsigned long sig[_NSIG_WORDS];
         |         ^
   In file included from drivers/gpio/gpio-fxl6408.c:12:
   In file included from include/linux/i2c.h:13:
   In file included from include/linux/acpi.h:14:
   In file included from include/linux/device.h:32:
   In file included from include/linux/device/driver.h:21:
   In file included from include/linux/module.h:20:
   In file included from include/linux/elf.h:6:
   In file included from arch/x86/include/asm/elf.h:10:
   In file included from arch/x86/include/asm/ia32.h:7:
   In file included from include/linux/compat.h:17:
   In file included from include/linux/fs.h:34:
   In file included from include/linux/percpu-rwsem.h:7:
   In file included from include/linux/rcuwait.h:6:
   In file included from include/linux/sched/signal.h:6:
   include/linux/signal.h:99:4: warning: array index 1 is past the end of the array (that has type 'unsigned long[1]') [-Warray-bounds]
      99 |                         set->sig[1] | set->sig[0]) == 0;
         |                         ^        ~
   arch/x86/include/asm/signal.h:24:2: note: array 'sig' declared here
      24 |         unsigned long sig[_NSIG_WORDS];
         |         ^
   In file included from drivers/gpio/gpio-fxl6408.c:12:
   In file included from include/linux/i2c.h:13:
   In file included from include/linux/acpi.h:14:
   In file included from include/linux/device.h:32:
   In file included from include/linux/device/driver.h:21:
   In file included from include/linux/module.h:20:
   In file included from include/linux/elf.h:6:
   In file included from arch/x86/include/asm/elf.h:10:
   In file included from arch/x86/include/asm/ia32.h:7:
   In file included from include/linux/compat.h:17:
   In file included from include/linux/fs.h:34:
   In file included from include/linux/percpu-rwsem.h:7:
   In file included from include/linux/rcuwait.h:6:
   In file included from include/linux/sched/signal.h:6:
   include/linux/signal.h:101:11: warning: array index 1 is past the end of the array (that has type 'unsigned long[1]') [-Warray-bounds]
     101 |                 return (set->sig[1] | set->sig[0]) == 0;
         |                         ^        ~
   arch/x86/include/asm/signal.h:24:2: note: array 'sig' declared here
      24 |         unsigned long sig[_NSIG_WORDS];
         |         ^
   In file included from drivers/gpio/gpio-fxl6408.c:12:
   In file included from include/linux/i2c.h:13:
   In file included from include/linux/acpi.h:14:
   In file included from include/linux/device.h:32:
   In file included from include/linux/device/driver.h:21:
   In file included from include/linux/module.h:20:
   In file included from include/linux/elf.h:6:
   In file included from arch/x86/include/asm/elf.h:10:
   In file included from arch/x86/include/asm/ia32.h:7:
   In file included from include/linux/compat.h:17:
   In file included from include/linux/fs.h:34:
   In file included from include/linux/percpu-rwsem.h:7:
   In file included from include/linux/rcuwait.h:6:
   In file included from include/linux/sched/signal.h:6:
   include/linux/signal.h:114:11: warning: array index 3 is past the end of the array (that has type 'const unsigned long[1]') [-Warray-bounds]
     114 |                 return  (set1->sig[3] == set2->sig[3]) &&
         |                          ^         ~
   arch/x86/include/asm/signal.h:24:2: note: array 'sig' declared here


vim +/BIT +26 include/linux/gpio/regmap.h

    14	
    15	
    16	/**
    17	 * enum gpio_regmap_flags - flags to control GPIO operation
    18	 */
    19	enum gpio_regmap_flags {
    20		/**
    21		 * @GPIO_REGMAP_DIR_BEFORE_SET: when setting a pin as an output, set
    22		 * its direction before the value. The output value will be undefined
    23		 * for a short time which may have unwanted side effects, but some
    24		 * hardware requires this.
    25		 */
  > 26		GPIO_REGMAP_DIR_BEFORE_SET	= BIT(0),
    27	};
    28	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Re: [PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
Posted by Marcos Del Sol Vives 1 month, 1 week ago
El 22/08/2025 a las 5:27, kernel test robot escribió:
> Hi Marcos,
> 
> kernel test robot noticed the following build errors:
> 
> [auto build test ERROR on brgl/gpio/for-next]
> [also build test ERROR on lee-mfd/for-mfd-next lee-mfd/for-mfd-fixes pci/next pci/for-linus linus/master v6.17-rc2 next-20250821]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Marcos-Del-Sol-Vives/gpio-gpio-regmap-add-flags-to-control-some-behaviour/20250821-182416
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git gpio/for-next
> patch link:    https://lore.kernel.org/r/20250821101902.626329-2-marcos%40orca.pet
> patch subject: [PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
> config: x86_64-buildonly-randconfig-001-20250822 (https://download.01.org/0day-ci/archive/20250822/202508221142.ETxcEpjA-lkp@intel.com/config)
> compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250822/202508221142.ETxcEpjA-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202508221142.ETxcEpjA-lkp@intel.com/
> 
> All errors (new ones prefixed by >>):
> 
>    In file included from drivers/gpio/gpio-fxl6408.c:11:
>>> include/linux/gpio/regmap.h:26:31: error: call to undeclared function 'BIT'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
>       26 |         GPIO_REGMAP_DIR_BEFORE_SET      = BIT(0),
>          |                                           ^
>>> include/linux/gpio/regmap.h:26:31: error: expression is not an integer constant expression
>       26 |         GPIO_REGMAP_DIR_BEFORE_SET      = BIT(0),
>          |                                           ^~~~~~
>    In file included from drivers/gpio/gpio-fxl6408.c:12:
>    In file included from include/linux/i2c.h:13:
>    In file included from include/linux/acpi.h:14:
>    In file included from include/linux/device.h:32:
>    In file included from include/linux/device/driver.h:21:
>    In file included from include/linux/module.h:20:
>    In file included from include/linux/elf.h:6:
>    In file included from arch/x86/include/asm/elf.h:10:
>    In file included from arch/x86/include/asm/ia32.h:7:
>    In file included from include/linux/compat.h:17:
>    In file included from include/linux/fs.h:34:
>    In file included from include/linux/percpu-rwsem.h:7:
>    In file included from include/linux/rcuwait.h:6:
>    In file included from include/linux/sched/signal.h:6:
>    include/linux/signal.h:98:11: warning: array index 3 is past the end of the array (that has type 'unsigned long[1]') [-Warray-bounds]
This is correct, thanks. I added a missing "#include <linux/bits.h>" to
fix it. Will be in a v4 of the patch set.
Re: [PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
Posted by Linus Walleij 1 month, 1 week ago
On Thu, Aug 21, 2025 at 12:19 PM Marcos Del Sol Vives <marcos@orca.pet> wrote:

>  static int gpio_regmap_direction_output(struct gpio_chip *chip,
>                                         unsigned int offset, int value)
>  {
> -       gpio_regmap_set(chip, offset, value);
> +       struct gpio_regmap *gpio = gpiochip_get_data(chip);
> +       int ret;
> +
> +       if (gpio->flags & GPIO_REGMAP_DIR_BEFORE_SET) {
> +               ret = gpio_regmap_set_direction(chip, offset, true);
> +               if (ret)
> +                       return ret;
> +
> +               return gpio_regmap_set(chip, offset, value);
> +       }
> +
> +       ret = gpio_regmap_set(chip, offset, value);
> +       if (ret)
> +               return ret;
>
>         return gpio_regmap_set_direction(chip, offset, true);

I guess this looks like this because it is just copied from
gpio-mmio.c:

static int bgpio_simple_dir_out(struct gpio_chip *gc, unsigned int gpio,
                                int val)
{
        gc->set(gc, gpio, val);

        return bgpio_dir_return(gc, gpio, true);
}

It's hard to know which semantic to employ here, it's one
way or the other.

I like the new flag.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

You can merge this with the rest of the series.

Yours,
Linus Walleij
Re: [PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
Posted by Michael Walle 1 month, 1 week ago
Hi,

On Thu Aug 21, 2025 at 6:40 PM CEST, Linus Walleij wrote:
> On Thu, Aug 21, 2025 at 12:19 PM Marcos Del Sol Vives <marcos@orca.pet> wrote:
>
> >  static int gpio_regmap_direction_output(struct gpio_chip *chip,
> >                                         unsigned int offset, int value)
> >  {
> > -       gpio_regmap_set(chip, offset, value);
> > +       struct gpio_regmap *gpio = gpiochip_get_data(chip);
> > +       int ret;
> > +
> > +       if (gpio->flags & GPIO_REGMAP_DIR_BEFORE_SET) {
> > +               ret = gpio_regmap_set_direction(chip, offset, true);
> > +               if (ret)
> > +                       return ret;
> > +
> > +               return gpio_regmap_set(chip, offset, value);
> > +       }
> > +
> > +       ret = gpio_regmap_set(chip, offset, value);
> > +       if (ret)
> > +               return ret;

Could you add a short paragraph to the commit message that you've
added error checking? Something like:

  While at it, add the missing error check in
  gpio_regmap_direction_output().

> >
> >         return gpio_regmap_set_direction(chip, offset, true);
>
> I guess this looks like this because it is just copied from
> gpio-mmio.c:

Yeah probably :)

With that above fixed:

Reviewed-by: Michael Walle <mwalle@kernel.org>
Re: [PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
Posted by Marcos Del Sol Vives 1 month, 1 week ago
El 22/08/2025 a las 9:07, Michael Walle escribió:
>>> +       ret = gpio_regmap_set(chip, offset, value);
>>> +       if (ret)
>>> +               return ret;
> 
> Could you add a short paragraph to the commit message that you've
> added error checking? Something like:
> 
>   While at it, add the missing error check in
>   gpio_regmap_direction_output().
> 

Added! Thanks for the feedback!
Re: [PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
Posted by Bjorn Helgaas 1 month, 1 week ago
Not my area, but consider making the subject more specific, e.g.,
"add flag to set direction before value"

On Thu, Aug 21, 2025 at 12:18:57PM +0200, Marcos Del Sol Vives wrote:
> The Vortex86 family of SoCs need the direction set before the value, else
> writes to the DATA ports are ignored.
> 
> This commit adds a new "flags" field plus a flag to change the default
> behaviour, which is to set first the direction and then the value.

This sounds like the default behavior is to set direction, then value.
But from the patch, it looks like:

  - default: set value, then direction

  - with GPIO_REGMAP_DIR_BEFORE_SET: set direction, then value

> Signed-off-by: Marcos Del Sol Vives <marcos@orca.pet>
> ---
>  drivers/gpio/gpio-regmap.c  | 17 ++++++++++++++++-
>  include/linux/gpio/regmap.h | 17 +++++++++++++++++
>  2 files changed, 33 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
> index e8a32dfebdcb..24cefbd57637 100644
> --- a/drivers/gpio/gpio-regmap.c
> +++ b/drivers/gpio/gpio-regmap.c
> @@ -31,6 +31,7 @@ struct gpio_regmap {
>  	unsigned int reg_clr_base;
>  	unsigned int reg_dir_in_base;
>  	unsigned int reg_dir_out_base;
> +	unsigned int flags;
>  
>  	int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
>  			      unsigned int offset, unsigned int *reg,
> @@ -196,7 +197,20 @@ static int gpio_regmap_direction_input(struct gpio_chip *chip,
>  static int gpio_regmap_direction_output(struct gpio_chip *chip,
>  					unsigned int offset, int value)
>  {
> -	gpio_regmap_set(chip, offset, value);
> +	struct gpio_regmap *gpio = gpiochip_get_data(chip);
> +	int ret;
> +
> +	if (gpio->flags & GPIO_REGMAP_DIR_BEFORE_SET) {
> +		ret = gpio_regmap_set_direction(chip, offset, true);
> +		if (ret)
> +			return ret;
> +
> +		return gpio_regmap_set(chip, offset, value);
> +	}
> +
> +	ret = gpio_regmap_set(chip, offset, value);
> +	if (ret)
> +		return ret;
>  
>  	return gpio_regmap_set_direction(chip, offset, true);
>  }
> @@ -247,6 +261,7 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
>  	gpio->reg_clr_base = config->reg_clr_base;
>  	gpio->reg_dir_in_base = config->reg_dir_in_base;
>  	gpio->reg_dir_out_base = config->reg_dir_out_base;
> +	gpio->flags = config->flags;
>  
>  	chip = &gpio->gpio_chip;
>  	chip->parent = config->parent;
> diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h
> index c722c67668c6..aea107e71fec 100644
> --- a/include/linux/gpio/regmap.h
> +++ b/include/linux/gpio/regmap.h
> @@ -12,6 +12,20 @@ struct regmap;
>  #define GPIO_REGMAP_ADDR_ZERO ((unsigned int)(-1))
>  #define GPIO_REGMAP_ADDR(addr) ((addr) ? : GPIO_REGMAP_ADDR_ZERO)
>  
> +
> +/**
> + * enum gpio_regmap_flags - flags to control GPIO operation
> + */
> +enum gpio_regmap_flags {
> +	/**
> +	 * @GPIO_REGMAP_DIR_BEFORE_SET: when setting a pin as an output, set
> +	 * its direction before the value. The output value will be undefined
> +	 * for a short time which may have unwanted side effects, but some
> +	 * hardware requires this.
> +	 */
> +	GPIO_REGMAP_DIR_BEFORE_SET	= BIT(0),
> +};
> +
>  /**
>   * struct gpio_regmap_config - Description of a generic regmap gpio_chip.
>   * @parent:		The parent device
> @@ -23,6 +37,8 @@ struct regmap;
>   *			If not given, the name of the device is used.
>   * @ngpio:		(Optional) Number of GPIOs
>   * @names:		(Optional) Array of names for gpios
> + * @flags:		(Optional) A bitmask of flags from
> + * 			&enum gpio_regmap_flags
>   * @reg_dat_base:	(Optional) (in) register base address
>   * @reg_set_base:	(Optional) set register base address
>   * @reg_clr_base:	(Optional) clear register base address
> @@ -68,6 +84,7 @@ struct gpio_regmap_config {
>  	const char *label;
>  	int ngpio;
>  	const char *const *names;
> +	unsigned int flags;
>  
>  	unsigned int reg_dat_base;
>  	unsigned int reg_set_base;
> -- 
> 2.34.1
>
Re: [PATCH v3 1/3] gpio: gpio-regmap: add flags to control some behaviour
Posted by Marcos Del Sol Vives 1 month, 1 week ago
El 21/08/2025 a las 16:32, Bjorn Helgaas escribió:
> Not my area, but consider making the subject more specific, e.g.,
> "add flag to set direction before value"
> 
> On Thu, Aug 21, 2025 at 12:18:57PM +0200, Marcos Del Sol Vives wrote:
>> The Vortex86 family of SoCs need the direction set before the value, else
>> writes to the DATA ports are ignored.
>>
>> This commit adds a new "flags" field plus a flag to change the default
>> behaviour, which is to set first the direction and then the value.
> 
> This sounds like the default behavior is to set direction, then value.
> But from the patch, it looks like:
> 
>   - default: set value, then direction
> 
>   - with GPIO_REGMAP_DIR_BEFORE_SET: set direction, then value
> 

Noted, thanks for the feedback! I've amended the commit and now it reads:

> gpio: gpio-regmap: add flag to set direction before value
>
> When configuring a pin as an output, the gpio-regmap driver by default
> writes first to the the value register, and then configures the direction.
>
> The Vortex86 family of SoCs, however, need the direction set before the
> value, else writes to the data ports are ignored.
>
> This commit adds a new "flags" field plus a flag to reverse that order,
> allowing the direction to be set before the value.

Hope that looks more clear!

Thanks,
Marcos