Re: [PATCH v1 1/4] mfd: stmpe: Probe sub-function by compatible

[Lee Jones]

On Tue, 12 Jul 2022, Francesco Dolcini wrote:

> Use sub-function of_compatible during probe, instead of using the node
> name. The code should not rely on the node names during probe, in
> addition to that the previously hard-coded node names are not compliant
> to the latest naming convention (they are not generic and they use
> underscores), and it was broken by mistake already once [1].
> 
> While doing this change `rotator` entry was removed, it is not
> used in any device tree file, there is no cell defined, it's just dead
> non-working code with no of_compatible for it.
> 
> [1] commit 56086b5e804f ("ARM: dts: imx6qdl-apalis: Avoid underscore in node name")
> 
> Suggested-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
> Signed-off-by: Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx>
> ---
>  drivers/mfd/stmpe.c | 31 +++++++++++++++++--------------
>  1 file changed, 17 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/mfd/stmpe.c b/drivers/mfd/stmpe.c
> index aeb9ea55f97d..90a07a94455f 100644
> --- a/drivers/mfd/stmpe.c
> +++ b/drivers/mfd/stmpe.c
> @@ -23,6 +23,12 @@
>  #include <linux/regulator/consumer.h>
>  #include "stmpe.h"
>  
> +#define STMPE_GPIO_COMPATIBLE   "st,stmpe-gpio"
> +#define STMPE_KEYPAD_COMPATIBLE "st,stmpe-keypad"
> +#define STMPE_PWM_COMPATIBLE    "st,stmpe-pwm"
> +#define STMPE_TS_COMPATIBLE     "st,stmpe-ts"
> +#define STMPE_ADC_COMPATIBLE    "st,stmpe-adc"

This is horrible.

Please refrain from defining device/compatible strings.

>  /**
>   * struct stmpe_platform_data - STMPE platform data
>   * @id: device id to distinguish between multiple STMPEs on the same board
> @@ -321,14 +327,14 @@ static struct resource stmpe_gpio_resources[] = {
>  
>  static const struct mfd_cell stmpe_gpio_cell = {
>  	.name		= "stmpe-gpio",
> -	.of_compatible	= "st,stmpe-gpio",
> +	.of_compatible	= STMPE_GPIO_COMPATIBLE,
>  	.resources	= stmpe_gpio_resources,
>  	.num_resources	= ARRAY_SIZE(stmpe_gpio_resources),
>  };
>  
>  static const struct mfd_cell stmpe_gpio_cell_noirq = {
>  	.name		= "stmpe-gpio",
> -	.of_compatible	= "st,stmpe-gpio",
> +	.of_compatible	= STMPE_GPIO_COMPATIBLE,
>  	/* gpio cell resources consist of an irq only so no resources here */
>  };
>  
> @@ -350,7 +356,7 @@ static struct resource stmpe_keypad_resources[] = {
>  
>  static const struct mfd_cell stmpe_keypad_cell = {
>  	.name		= "stmpe-keypad",
> -	.of_compatible  = "st,stmpe-keypad",
> +	.of_compatible  = STMPE_KEYPAD_COMPATIBLE,
>  	.resources	= stmpe_keypad_resources,
>  	.num_resources	= ARRAY_SIZE(stmpe_keypad_resources),
>  };
> @@ -376,7 +382,7 @@ static struct resource stmpe_pwm_resources[] = {
>  
>  static const struct mfd_cell stmpe_pwm_cell = {
>  	.name		= "stmpe-pwm",
> -	.of_compatible  = "st,stmpe-pwm",
> +	.of_compatible  = STMPE_PWM_COMPATIBLE,
>  	.resources	= stmpe_pwm_resources,
>  	.num_resources	= ARRAY_SIZE(stmpe_pwm_resources),
>  };
> @@ -461,7 +467,7 @@ static struct resource stmpe_ts_resources[] = {
>  
>  static const struct mfd_cell stmpe_ts_cell = {
>  	.name		= "stmpe-ts",
> -	.of_compatible	= "st,stmpe-ts",
> +	.of_compatible	= STMPE_TS_COMPATIBLE,
>  	.resources	= stmpe_ts_resources,
>  	.num_resources	= ARRAY_SIZE(stmpe_ts_resources),
>  };
> @@ -484,7 +490,7 @@ static struct resource stmpe_adc_resources[] = {
>  
>  static const struct mfd_cell stmpe_adc_cell = {
>  	.name		= "stmpe-adc",
> -	.of_compatible	= "st,stmpe-adc",
> +	.of_compatible	= STMPE_ADC_COMPATIBLE,
>  	.resources	= stmpe_adc_resources,
>  	.num_resources	= ARRAY_SIZE(stmpe_adc_resources),
>  };
> @@ -1362,19 +1368,16 @@ static void stmpe_of_probe(struct stmpe_platform_data *pdata,
>  	pdata->autosleep = (pdata->autosleep_timeout) ? true : false;
>  
>  	for_each_available_child_of_node(np, child) {
> -		if (of_node_name_eq(child, "stmpe_gpio")) {
> +		if (of_device_is_compatible(child, STMPE_GPIO_COMPATIBLE))
>  			pdata->blocks |= STMPE_BLOCK_GPIO;
> -		} else if (of_node_name_eq(child, "stmpe_keypad")) {
> +		else if (of_device_is_compatible(child, STMPE_KEYPAD_COMPATIBLE))
>  			pdata->blocks |= STMPE_BLOCK_KEYPAD;
> -		} else if (of_node_name_eq(child, "stmpe_touchscreen")) {
> +		else if (of_device_is_compatible(child, STMPE_TS_COMPATIBLE))
>  			pdata->blocks |= STMPE_BLOCK_TOUCHSCREEN;
> -		} else if (of_node_name_eq(child, "stmpe_adc")) {
> +		else if (of_device_is_compatible(child, STMPE_ADC_COMPATIBLE))
>  			pdata->blocks |= STMPE_BLOCK_ADC;
> -		} else if (of_node_name_eq(child, "stmpe_pwm")) {
> +		else if (of_device_is_compatible(child, STMPE_PWM_COMPATIBLE))
>  			pdata->blocks |= STMPE_BLOCK_PWM;
> -		} else if (of_node_name_eq(child, "stmpe_rotator")) {
> -			pdata->blocks |= STMPE_BLOCK_ROTATOR;
> -		}

This should be a separate patch.

>  	}
>  }
>  

-- 
Lee Jones [李琼斯]
Principal Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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