[PATCH] gpio: ds4520: don't check the 'ngpios' property in the driver

[PATCH] gpio: ds4520: don't check the 'ngpios' property in the driver

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

This is already done by the gpio-regmap abstraction by calling
gpiochip_get_ngpios(). We don't need to do this at the driver level.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 drivers/gpio/gpio-ds4520.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/gpio/gpio-ds4520.c b/drivers/gpio/gpio-ds4520.c
index 1903deaef3e9..2390f53dae46 100644
--- a/drivers/gpio/gpio-ds4520.c
+++ b/drivers/gpio/gpio-ds4520.c
@@ -33,10 +33,6 @@ static int ds4520_gpio_probe(struct i2c_client *client)
 	if (ret)
 		return dev_err_probe(dev, ret, "Missing 'reg' property.\n");
 
-	ret = device_property_read_u32(dev, "ngpios", &ngpio);
-	if (ret)
-		return dev_err_probe(dev, ret, "Missing 'ngpios' property.\n");
-
 	regmap = devm_regmap_init_i2c(client, &ds4520_regmap_config);
 	if (IS_ERR(regmap))
 		return dev_err_probe(dev, PTR_ERR(regmap),

---
base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8
change-id: 20250326-gpio-regmap-ngpios-e16aae1f0c98

Best regards,
-- 
Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Re: [PATCH] gpio: ds4520: don't check the 'ngpios' property in the driver

[kernel test robot]

Hi Bartosz,

kernel test robot noticed the following build warnings:

[auto build test WARNING on 0af2f6be1b4281385b618cb86ad946eded089ac8]

url:    https://github.com/intel-lab-lkp/linux/commits/Bartosz-Golaszewski/gpio-ds4520-don-t-check-the-ngpios-property-in-the-driver/20250407-150804
base:   0af2f6be1b4281385b618cb86ad946eded089ac8
patch link:    https://lore.kernel.org/r/20250407-gpio-regmap-ngpios-v1-1-5ea63fcbde39%40linaro.org
patch subject: [PATCH] gpio: ds4520: don't check the 'ngpios' property in the driver
config: arm-randconfig-002-20250407 (https://download.01.org/0day-ci/archive/20250407/202504072320.SjnRj58d-lkp@intel.com/config)
compiler: clang version 21.0.0git (https://github.com/llvm/llvm-project 92c93f5286b9ff33f27ff694d2dc33da1c07afdd)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250407/202504072320.SjnRj58d-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/202504072320.SjnRj58d-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/gpio/gpio-ds4520.c:43:17: warning: variable 'ngpio' is uninitialized when used here [-Wuninitialized]
      43 |         config.ngpio = ngpio;
         |                        ^~~~~
   drivers/gpio/gpio-ds4520.c:28:11: note: initialize the variable 'ngpio' to silence this warning
      28 |         u32 ngpio;
         |                  ^
         |                   = 0
   1 warning generated.


vim +/ngpio +43 drivers/gpio/gpio-ds4520.c

659ad5f7efece8 Okan Sahin 2023-07-29  22  
659ad5f7efece8 Okan Sahin 2023-07-29  23  static int ds4520_gpio_probe(struct i2c_client *client)
659ad5f7efece8 Okan Sahin 2023-07-29  24  {
659ad5f7efece8 Okan Sahin 2023-07-29  25  	struct gpio_regmap_config config = { };
659ad5f7efece8 Okan Sahin 2023-07-29  26  	struct device *dev = &client->dev;
659ad5f7efece8 Okan Sahin 2023-07-29  27  	struct regmap *regmap;
659ad5f7efece8 Okan Sahin 2023-07-29  28  	u32 ngpio;
659ad5f7efece8 Okan Sahin 2023-07-29  29  	u32 base;
659ad5f7efece8 Okan Sahin 2023-07-29  30  	int ret;
659ad5f7efece8 Okan Sahin 2023-07-29  31  
659ad5f7efece8 Okan Sahin 2023-07-29  32  	ret = device_property_read_u32(dev, "reg", &base);
659ad5f7efece8 Okan Sahin 2023-07-29  33  	if (ret)
659ad5f7efece8 Okan Sahin 2023-07-29  34  		return dev_err_probe(dev, ret, "Missing 'reg' property.\n");
659ad5f7efece8 Okan Sahin 2023-07-29  35  
659ad5f7efece8 Okan Sahin 2023-07-29  36  	regmap = devm_regmap_init_i2c(client, &ds4520_regmap_config);
659ad5f7efece8 Okan Sahin 2023-07-29  37  	if (IS_ERR(regmap))
659ad5f7efece8 Okan Sahin 2023-07-29  38  		return dev_err_probe(dev, PTR_ERR(regmap),
659ad5f7efece8 Okan Sahin 2023-07-29  39  				     "Failed to allocate register map\n");
659ad5f7efece8 Okan Sahin 2023-07-29  40  
659ad5f7efece8 Okan Sahin 2023-07-29  41  	config.regmap = regmap;
659ad5f7efece8 Okan Sahin 2023-07-29  42  	config.parent = dev;
659ad5f7efece8 Okan Sahin 2023-07-29 @43  	config.ngpio = ngpio;
659ad5f7efece8 Okan Sahin 2023-07-29  44  
659ad5f7efece8 Okan Sahin 2023-07-29  45  	config.reg_dat_base = base + DS4520_IO_STATUS0;
659ad5f7efece8 Okan Sahin 2023-07-29  46  	config.reg_set_base = base + DS4520_PULLUP0;
659ad5f7efece8 Okan Sahin 2023-07-29  47  	config.reg_dir_out_base = base + DS4520_IO_CONTROL0;
659ad5f7efece8 Okan Sahin 2023-07-29  48  
659ad5f7efece8 Okan Sahin 2023-07-29  49  	return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(dev, &config));
659ad5f7efece8 Okan Sahin 2023-07-29  50  }
659ad5f7efece8 Okan Sahin 2023-07-29  51  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki