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

From: Ludovic Desroches
Date: Sat Sep 14 2019 - 15:36:44 EST


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@xxxxxxxxxxx>

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

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
>
>