Re: [PATCH] pinctrl: at91-pio4: implement .get_multiple and .set_multiple

[Ludovic Desroches <ludovic.desroches@microchip.com>]

On Thu, Sep 05, 2019 at 04:13:04PM +0200, Alexandre Belloni wrote:
> 
> Implement .get_multiple and .set_multiple to allow reading or setting
> multiple pins simultaneously. Pins in the same bank will all be switched at
> the same time, improving synchronization and performances.
> 
> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>

Thanks for this improvement. You can keep my ack for v3 as the changes
should be the commit message only. I'll be off for three weeks.

Regards

Ludovic

> ---
>  drivers/pinctrl/pinctrl-at91-pio4.c | 60 +++++++++++++++++++++++++++++
>  1 file changed, 60 insertions(+)
> 
> diff --git a/drivers/pinctrl/pinctrl-at91-pio4.c b/drivers/pinctrl/pinctrl-at91-pio4.c
> index d6de4d360cd4..488a302a60d4 100644
> --- a/drivers/pinctrl/pinctrl-at91-pio4.c
> +++ b/drivers/pinctrl/pinctrl-at91-pio4.c
> @@ -328,6 +328,35 @@ static int atmel_gpio_get(struct gpio_chip *chip, unsigned offset)
>  	return !!(reg & BIT(pin->line));
>  }
>  
> +static int atmel_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask,
> +				   unsigned long *bits)
> +{
> +	struct atmel_pioctrl *atmel_pioctrl = gpiochip_get_data(chip);
> +	unsigned int bank;
> +
> +	bitmap_zero(bits, atmel_pioctrl->npins);
> +
> +	for (bank = 0; bank < atmel_pioctrl->nbanks; bank++) {
> +		unsigned int word = bank;
> +		unsigned int offset = 0;
> +		unsigned int reg;
> +
> +#if ATMEL_PIO_NPINS_PER_BANK != BITS_PER_LONG
> +		word = BIT_WORD(bank * ATMEL_PIO_NPINS_PER_BANK);
> +		offset = bank * ATMEL_PIO_NPINS_PER_BANK % BITS_PER_LONG;
> +#endif
> +		if (!mask[word])
> +			continue;
> +
> +		reg = atmel_gpio_read(atmel_pioctrl, bank, ATMEL_PIO_PDSR);
> +		bits[word] |= mask[word] & (reg << offset);
> +
> +		pr_err("ABE: %d %08x\n", bank, bits[word]);
> +	}
> +
> +	return 0;
> +}
> +
>  static int atmel_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
>  				       int value)
>  {
> @@ -358,11 +387,42 @@ static void atmel_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
>  			 BIT(pin->line));
>  }
>  
> +static void atmel_gpio_set_multiple(struct gpio_chip *chip, unsigned long *mask,
> +				    unsigned long *bits)
> +{
> +	struct atmel_pioctrl *atmel_pioctrl = gpiochip_get_data(chip);
> +	unsigned int bank;
> +
> +	for (bank = 0; bank < atmel_pioctrl->nbanks; bank++) {
> +		unsigned int bitmask;
> +		unsigned int word = bank;
> +
> +#if ATMEL_PIO_NPINS_PER_BANK != BITS_PER_LONG
> +		word = BIT_WORD(bank * ATMEL_PIO_NPINS_PER_BANK);
> +#endif
> +		if (!mask[word])
> +			continue;
> +
> +		bitmask = mask[word] & bits[word];
> +		atmel_gpio_write(atmel_pioctrl, bank, ATMEL_PIO_SODR, bitmask);
> +
> +		bitmask = mask[word] & ~bits[word];
> +		atmel_gpio_write(atmel_pioctrl, bank, ATMEL_PIO_CODR, bitmask);
> +
> +#if ATMEL_PIO_NPINS_PER_BANK != BITS_PER_LONG
> +		mask[word] >>= ATMEL_PIO_NPINS_PER_BANK;
> +		bits[word] >>= ATMEL_PIO_NPINS_PER_BANK;
> +#endif
> +	}
> +}
> +
>  static struct gpio_chip atmel_gpio_chip = {
>  	.direction_input        = atmel_gpio_direction_input,
>  	.get                    = atmel_gpio_get,
> +	.get_multiple           = atmel_gpio_get_multiple,
>  	.direction_output       = atmel_gpio_direction_output,
>  	.set                    = atmel_gpio_set,
> +	.set_multiple           = atmel_gpio_set_multiple,
>  	.to_irq                 = atmel_gpio_to_irq,
>  	.base                   = 0,
>  };
> -- 
> 2.21.0
> 
>