[PATCH v11 05/11] gpio: gpio-mm: Utilize for_each_set_clump8 macro

From: William Breathitt Gray
Date: Mon Mar 25 2019 - 02:03:44 EST


Replace verbose implementation in get_multiple/set_multiple callbacks
with for_each_set_clump8 macro to simplify code and improve clarity.

Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: William Breathitt Gray <vilhelm.gray@xxxxxxxxx>
---
drivers/gpio/gpio-gpio-mm.c | 73 +++++++++++--------------------------
1 file changed, 22 insertions(+), 51 deletions(-)

diff --git a/drivers/gpio/gpio-gpio-mm.c b/drivers/gpio/gpio-gpio-mm.c
index 8c150fd68d9d..4c1037a005ab 100644
--- a/drivers/gpio/gpio-gpio-mm.c
+++ b/drivers/gpio/gpio-gpio-mm.c
@@ -172,46 +172,26 @@ static int gpiomm_gpio_get(struct gpio_chip *chip, unsigned int offset)
return !!(port_state & mask);
}

+static const size_t ports[] = { 0, 1, 2, 4, 5, 6 };
+
static int gpiomm_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask,
unsigned long *bits)
{
struct gpiomm_gpio *const gpiommgpio = gpiochip_get_data(chip);
- size_t i;
- static const size_t ports[] = { 0, 1, 2, 4, 5, 6 };
- 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 int offset;
+ unsigned long gpio_mask;
+ const unsigned int ngpio = ARRAY_SIZE(ports) * 8;
+ unsigned int port_addr;
unsigned long port_state;

/* 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_state = inb(gpiommgpio->base + ports[i]);
+ for_each_set_clump8(offset, gpio_mask, mask, ngpio) {
+ port_addr = gpiommgpio->base + ports[offset / 8];
+ port_state = inb(port_addr) & gpio_mask;

- /* store acquired bits at respective bits array offset */
- bits[word_index] |= (port_state << word_offset) & word_mask;
+ bitmap_set_value8(bits, ngpio, port_state, offset);
}

return 0;
@@ -242,37 +222,28 @@ static void gpiomm_gpio_set_multiple(struct gpio_chip *chip,
unsigned long *mask, unsigned long *bits)
{
struct gpiomm_gpio *const gpiommgpio = gpiochip_get_data(chip);
- unsigned int i;
- const unsigned int gpio_reg_size = 8;
- unsigned int port;
- unsigned int out_port;
+ unsigned int offset;
+ unsigned long gpio_mask;
+ const unsigned int ngpio = ARRAY_SIZE(ports) * 8;
+ size_t index;
+ unsigned int port_addr;
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;
- }
+ for_each_set_clump8(offset, gpio_mask, mask, ngpio) {
+ index = offset / 8;
+ port_addr = gpiommgpio->base + ports[index];

- port = i / gpio_reg_size;
- out_port = (port > 2) ? port + 1 : port;
- bitmask = mask[BIT_WORD(i)] & bits[BIT_WORD(i)];
+ bitmask = bitmap_get_value8(bits, ngpio, offset) & gpio_mask;

spin_lock_irqsave(&gpiommgpio->lock, flags);

/* update output state data and set device gpio register */
- gpiommgpio->out_state[port] &= ~mask[BIT_WORD(i)];
- gpiommgpio->out_state[port] |= bitmask;
- outb(gpiommgpio->out_state[port], gpiommgpio->base + out_port);
+ gpiommgpio->out_state[index] &= ~gpio_mask;
+ gpiommgpio->out_state[index] |= bitmask;
+ outb(gpiommgpio->out_state[index], port_addr);

spin_unlock_irqrestore(&gpiommgpio->lock, flags);
-
- /* prepare for next gpio register set */
- mask[BIT_WORD(i)] >>= gpio_reg_size;
- bits[BIT_WORD(i)] >>= gpio_reg_size;
}
}

--
2.21.0