The ACCES 104-DIO-48E series provides registers where 8 lines of GPIO
may be set at a time. This patch add support for the set_multiple
callback function, thus allowing multiple GPIO output lines to be set
more efficiently in groups.
Signed-off-by: William Breathitt Gray <vilhelm.gray@xxxxxxxxx>
---
drivers/gpio/gpio-104-dio-48e.c | 39 +++++++++++++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)
diff --git a/drivers/gpio/gpio-104-dio-48e.c b/drivers/gpio/gpio-104-dio-48e.c
index fcf776971ca9..7bc891f1d11a 100644
--- a/drivers/gpio/gpio-104-dio-48e.c
+++ b/drivers/gpio/gpio-104-dio-48e.c
@@ -204,6 +204,44 @@ static void dio48e_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
spin_unlock_irqrestore(&dio48egpio->lock, flags);
}
+static void dio48e_gpio_set_multiple(struct gpio_chip *chip,
+ unsigned long *mask, unsigned long *bits)
+{
+ struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
+ unsigned int i;
+ const unsigned int gpio_reg_size = 8;
+ unsigned int port;
+ unsigned int out_port;
+ unsigned int bitmask;
+ unsigned long flags;
+
+ /* set bits are evaluated a gpio register size at a time */
+ for (i = 0; i < chip->ngpio; i += gpio_reg_size) {
+ /* no more set bits in this mask word; skip to the next word */
+ if (!mask[BIT_WORD(i)]) {
+ i = (BIT_WORD(i) + 1) * BITS_PER_LONG - gpio_reg_size;
+ continue;
+ }
+
+ port = i / gpio_reg_size;
+ out_port = (port > 2) ? port + 1 : port;
+ bitmask = mask[BIT_WORD(i)] & bits[BIT_WORD(i)];
+
+ spin_lock_irqsave(&dio48egpio->lock, flags);
+
+ /* update output state data and set device gpio register */
+ dio48egpio->out_state[port] &= ~mask[BIT_WORD(i)];
+ dio48egpio->out_state[port] |= bitmask;
+ outb(dio48egpio->out_state[port], dio48egpio->base + out_port);
+
+ spin_unlock_irqrestore(&dio48egpio->lock, flags);
+
+ /* prepare for next gpio register set */
+ mask[BIT_WORD(i)] >>= gpio_reg_size;
+ bits[BIT_WORD(i)] >>= gpio_reg_size;
+ }
+}
+
static void dio48e_irq_ack(struct irq_data *data)
{
}
@@ -328,6 +366,7 @@ static int dio48e_probe(struct device *dev, unsigned int id)
dio48egpio->chip.direction_output = dio48e_gpio_direction_output;
dio48egpio->chip.get = dio48e_gpio_get;
dio48egpio->chip.set = dio48e_gpio_set;
+ dio48egpio->chip.set_multiple = dio48e_gpio_set_multiple;
dio48egpio->base = base[id];
dio48egpio->irq = irq[id];
--
2.11.0
--
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