Re: [PATCH v6 2/3] Input: adp5588-keys - add support for pure gpio

["Nuno Sá" <noname.nuno@gmail.com>]

On Thu, 2024-07-04 at 11:45 +0100, Utsav Agarwal via B4 Relay wrote:
> From: Utsav Agarwal <utsav.agarwal@analog.com>
> 
> Keypad specific setup is relaxed if no keypad rows/columns are specified,
> enabling a purely gpio operation.
> 
> Signed-off-by: Utsav Agarwal <utsav.agarwal@analog.com>
> ---
>  drivers/input/keyboard/adp5588-keys.c | 27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/drivers/input/keyboard/adp5588-keys.c
> b/drivers/input/keyboard/adp5588-keys.c
> index 09bcfc6b9408..572335c8ef0f 100644
> --- a/drivers/input/keyboard/adp5588-keys.c
> +++ b/drivers/input/keyboard/adp5588-keys.c
> @@ -188,6 +188,7 @@ struct adp5588_kpad {
>  	u32 cols;
>  	u32 unlock_keys[2];
>  	int nkeys_unlock;
> +	bool gpio_only;
>  	unsigned short keycode[ADP5588_KEYMAPSIZE];
>  	unsigned char gpiomap[ADP5588_MAXGPIO];
>  	struct gpio_chip gc;
> @@ -632,6 +633,21 @@ static int adp5588_fw_parse(struct adp5588_kpad *kpad)
>  	struct i2c_client *client = kpad->client;
>  	int ret, i;
>  
> +	/*
> +	 * Check if the device is to be operated purely in GPIO mode. To do
> +	 * so, check that no keypad rows or columns have been specified,
> +	 * since all GPINS should be configured as GPIO.
> +	 */
> +	ret = device_property_present(&client->dev,
> +			"keypad,num-rows");
> +	ret |= device_property_present(&client->dev,
> +			"keypad,num-columns");
> +	/* If purely GPIO, skip keypad setup */
> +	if (!ret) {
> +		kpad->gpio_only = true;
> +		return 0;
> +	}
> +
>  	ret = matrix_keypad_parse_properties(&client->dev, &kpad->rows,
>  					     &kpad->cols);
>  	if (ret)
> @@ -775,6 +791,11 @@ static int adp5588_probe(struct i2c_client *client)
>  	if (error)
>  		return error;
>  
> +	if (kpad->gpio_only && !client->irq) {
> +		dev_info(&client->dev, "Rev.%d, started as GPIO only\n",
> revid);
> +		return 0;
> +	}

You're still missing something regarding interrupts. If there's no client->irq
then you should not setup the gpio_irq_chip. Hence, in adp5588_gpio_add(), you
should have:

if (kpad->client->irq) {
	girq = &kpad->gc.irq;
	gpio_irq_chip_set_chip(girq, &adp5588_irq_chip);
	girq->handler = handle_bad_irq;
	girq->threaded = true;
}

- Nuno Sá