From ca37081595a2fa1d67c962d416392d36ae8d05ad Mon Sep 17 00:00:00 2001 From: William Breathitt Gray Date: Thu, 22 Mar 2018 09:00:00 -0400 Subject: gpio: pcie-idio-24: Implement get_multiple/set_multiple callbacks The ACCES I/O PCIe-IDIO-24 series of devices provides 24 optically-isolated digital I/O accessed via six 8-bit ports. Since eight input lines are acquired on a single port input read -- and similarly eight output lines are set on a single port output write -- the PCIe-IDIO-24 GPIO driver may improve multiple I/O reads/writes by utilizing a get_multiple/set_multiple callbacks. This patch implements the idio_24_gpio_get_multiple function which serves as the respective get_multiple callback, and implements the idio_24_gpio_set_multiple function which serves as the respective set_multiple callback. Signed-off-by: William Breathitt Gray Signed-off-by: Linus Walleij --- drivers/gpio/gpio-pcie-idio-24.c | 117 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+) (limited to 'drivers/gpio/gpio-pcie-idio-24.c') diff --git a/drivers/gpio/gpio-pcie-idio-24.c b/drivers/gpio/gpio-pcie-idio-24.c index f666e2e69074..835607ecf658 100644 --- a/drivers/gpio/gpio-pcie-idio-24.c +++ b/drivers/gpio/gpio-pcie-idio-24.c @@ -15,6 +15,7 @@ * This driver supports the following ACCES devices: PCIe-IDIO-24, * PCIe-IDI-24, PCIe-IDO-24, and PCIe-IDIO-12. */ +#include #include #include #include @@ -193,6 +194,61 @@ static int idio_24_gpio_get(struct gpio_chip *chip, unsigned int offset) return !!(ioread8(&idio24gpio->reg->ttl_in0_7) & offset_mask); } +static int idio_24_gpio_get_multiple(struct gpio_chip *chip, + unsigned long *mask, unsigned long *bits) +{ + struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip); + size_t i; + const unsigned int gpio_reg_size = 8; + unsigned int bits_offset; + size_t word_index; + unsigned int word_offset; + unsigned long word_mask; + const unsigned long port_mask = GENMASK(gpio_reg_size - 1, 0); + unsigned long port_state; + u8 __iomem ports[] = { + idio24gpio->reg->out0_7, idio24gpio->reg->out8_15, + idio24gpio->reg->out16_23, idio24gpio->reg->in0_7, + idio24gpio->reg->in8_15, idio24gpio->reg->in16_23, + }; + const unsigned long out_mode_mask = BIT(1); + + /* clear bits array to a clean slate */ + bitmap_zero(bits, chip->ngpio); + + /* get bits are evaluated a gpio port register at a time */ + for (i = 0; i < ARRAY_SIZE(ports); i++) { + /* gpio offset in bits array */ + bits_offset = i * gpio_reg_size; + + /* word index for bits array */ + word_index = BIT_WORD(bits_offset); + + /* gpio offset within current word of bits array */ + word_offset = bits_offset % BITS_PER_LONG; + + /* mask of get bits for current gpio within current word */ + word_mask = mask[word_index] & (port_mask << word_offset); + if (!word_mask) { + /* no get bits in this port so skip to next one */ + continue; + } + + /* read bits from current gpio port (port 6 is TTL GPIO) */ + if (i < 6) + port_state = ioread8(ports + i); + else if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask) + port_state = ioread8(&idio24gpio->reg->ttl_out0_7); + else + port_state = ioread8(&idio24gpio->reg->ttl_in0_7); + + /* store acquired bits at respective bits array offset */ + bits[word_index] |= port_state << word_offset; + } + + return 0; +} + static void idio_24_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) { @@ -234,6 +290,65 @@ static void idio_24_gpio_set(struct gpio_chip *chip, unsigned int offset, raw_spin_unlock_irqrestore(&idio24gpio->lock, flags); } +static void idio_24_gpio_set_multiple(struct gpio_chip *chip, + unsigned long *mask, unsigned long *bits) +{ + struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip); + size_t i; + unsigned long bits_offset; + unsigned long gpio_mask; + const unsigned int gpio_reg_size = 8; + const unsigned long port_mask = GENMASK(gpio_reg_size, 0); + unsigned long flags; + unsigned int out_state; + u8 __iomem ports[] = { + idio24gpio->reg->out0_7, idio24gpio->reg->out8_15, + idio24gpio->reg->out16_23 + }; + const unsigned long out_mode_mask = BIT(1); + const unsigned int ttl_offset = 48; + const size_t ttl_i = BIT_WORD(ttl_offset); + const unsigned int word_offset = ttl_offset % BITS_PER_LONG; + const unsigned long ttl_mask = (mask[ttl_i] >> word_offset) & port_mask; + const unsigned long ttl_bits = (bits[ttl_i] >> word_offset) & ttl_mask; + + /* set bits are processed a gpio port register at a time */ + for (i = 0; i < ARRAY_SIZE(ports); i++) { + /* gpio offset in bits array */ + bits_offset = i * gpio_reg_size; + + /* check if any set bits for current port */ + gpio_mask = (*mask >> bits_offset) & port_mask; + if (!gpio_mask) { + /* no set bits for this port so move on to next port */ + continue; + } + + raw_spin_lock_irqsave(&idio24gpio->lock, flags); + + /* process output lines */ + out_state = ioread8(ports + i) & ~gpio_mask; + out_state |= (*bits >> bits_offset) & gpio_mask; + iowrite8(out_state, ports + i); + + raw_spin_unlock_irqrestore(&idio24gpio->lock, flags); + } + + /* check if setting TTL lines and if they are in output mode */ + if (!ttl_mask || !(ioread8(&idio24gpio->reg->ctl) & out_mode_mask)) + return; + + /* handle TTL output */ + raw_spin_lock_irqsave(&idio24gpio->lock, flags); + + /* process output lines */ + out_state = ioread8(&idio24gpio->reg->ttl_out0_7) & ~ttl_mask; + out_state |= ttl_bits; + iowrite8(out_state, &idio24gpio->reg->ttl_out0_7); + + raw_spin_unlock_irqrestore(&idio24gpio->lock, flags); +} + static void idio_24_irq_ack(struct irq_data *data) { } @@ -397,7 +512,9 @@ static int idio_24_probe(struct pci_dev *pdev, const struct pci_device_id *id) idio24gpio->chip.direction_input = idio_24_gpio_direction_input; idio24gpio->chip.direction_output = idio_24_gpio_direction_output; idio24gpio->chip.get = idio_24_gpio_get; + idio24gpio->chip.get_multiple = idio_24_gpio_get_multiple; idio24gpio->chip.set = idio_24_gpio_set; + idio24gpio->chip.set_multiple = idio_24_gpio_set_multiple; raw_spin_lock_init(&idio24gpio->lock); -- cgit v1.2.3-59-g8ed1b