[PATCH v8 4/8] gpio: 104-idi-48: Utilize for_each_set_clump8 macro

From: William Breathitt Gray
Date: Mon Jan 14 2019 - 01:20:11 EST


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

Signed-off-by: William Breathitt Gray <vilhelm.gray@xxxxxxxxx>
---
drivers/gpio/gpio-104-idi-48.c | 37 ++++++++--------------------------
1 file changed, 8 insertions(+), 29 deletions(-)

diff --git a/drivers/gpio/gpio-104-idi-48.c b/drivers/gpio/gpio-104-idi-48.c
index 88dc6f2449f6..59c571aecf9a 100644
--- a/drivers/gpio/gpio-104-idi-48.c
+++ b/drivers/gpio/gpio-104-idi-48.c
@@ -93,42 +93,21 @@ static int idi_48_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask,
unsigned long *bits)
{
struct idi_48_gpio *const idi48gpio = gpiochip_get_data(chip);
- size_t i;
+ unsigned int offset;
+ unsigned long gpio_mask;
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);
+ 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;
+ for_each_set_clump8(offset, gpio_mask, mask, ngpio) {
+ port_addr = idi48gpio->base + ports[offset / 8];
+ port_state = inb(port_addr) & gpio_mask;

- /* 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(idi48gpio->base + ports[i]);
-
- /* 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;
--
2.20.1