Re: [PATCH] Input: tca8418 - Add support for shared interrupt

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

Hi Alban,

On Mon, Nov 05, 2012 at 05:14:12PM +0100, Alban Bedel wrote:
> Signed-off-by: Alban Bedel <alban.bedel@avionic-design.de>
> ---
>  drivers/input/keyboard/tca8418_keypad.c |   10 +++++++---
>  1 files changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/input/keyboard/tca8418_keypad.c b/drivers/input/keyboard/tca8418_keypad.c
> index fc9cc94..5adc655 100644
> --- a/drivers/input/keyboard/tca8418_keypad.c
> +++ b/drivers/input/keyboard/tca8418_keypad.c
> @@ -225,16 +225,18 @@ static irqreturn_t tca8418_irq_handler(int irq, void *dev_id)
>  	if (error) {
>  		dev_err(&keypad_data->client->dev,
>  			"unable to read REG_INT_STAT\n");
> -		goto exit;
> +		return IRQ_NONE;
>  	}
>  
> +	if (!reg)
> +		return IRQ_NONE;
> +
>  	if (reg & INT_STAT_OVR_FLOW_INT)
>  		dev_warn(&keypad_data->client->dev, "overflow occurred\n");
>  
>  	if (reg & INT_STAT_K_INT)
>  		tca8418_read_keypad(keypad_data);
>  
> -exit:
>  	/* Clear all interrupts, even IRQs we didn't check (GPI, CAD, LCK) */
>  	reg = 0xff;
>  	error = tca8418_write_byte(keypad_data, REG_INT_STAT, reg);
> @@ -377,7 +379,9 @@ static int __devinit tca8418_keypad_probe(struct i2c_client *client,
>  		client->irq = gpio_to_irq(client->irq);
>  
>  	error = request_threaded_irq(client->irq, NULL, tca8418_irq_handler,
> -				     IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> +				     IRQF_TRIGGER_FALLING |
> +				     IRQF_SHARED |
> +				     IRQF_ONESHOT,
>  				     client->name, keypad_data);

I do not think that using ONESHOT IRQ handlers in shared interrupt
configuration is a good idea as that interrupt will stay masked until
the keypad is done processing it, which may take some time.

Thanks.

-- 
Dmitry