From 09107a51b096fbac3ea32d9ea150ddf029cbc358 Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Wed, 18 Sep 2019 13:36:57 +0200 Subject: [PATCH] pinctrl: at91-pio4: implement .get_multiple and .set_multiple 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. Keep the driver future proof by allowing its use on 64bits platforms if they ever appear with this IP and we end up with a mismatch between ATMEL_PIO_NPINS_PER_BANK and BITS_PER_LONG. Signed-off-by: Alexandre Belloni Acked-by: Ludovic Desroches Link: https://lore.kernel.org/r/20190918113657.25998-1-alexandre.belloni@bootlin.com Signed-off-by: Linus Walleij --- drivers/pinctrl/pinctrl-at91-pio4.c | 62 +++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) diff --git a/drivers/pinctrl/pinctrl-at91-pio4.c b/drivers/pinctrl/pinctrl-at91-pio4.c index d6de4d36..e380202 100644 --- a/drivers/pinctrl/pinctrl-at91-pio4.c +++ b/drivers/pinctrl/pinctrl-at91-pio4.c @@ -328,6 +328,33 @@ 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); + } + + return 0; +} + static int atmel_gpio_direction_output(struct gpio_chip *chip, unsigned offset, int value) { @@ -358,11 +385,46 @@ 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; + +/* + * On a 64-bit platform, BITS_PER_LONG is 64 so it is necessary to iterate over + * two 32bit words to handle the whole bitmask + */ +#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, }; -- 2.7.4