[PATCH v12 11/11] gpio: 74x164: Utilize the for_each_set_clump8 macro

From: William Breathitt Gray
Date: Mon Mar 25 2019 - 02:25:27 EST


Replace verbose implementation in set_multiple callback with
for_each_set_clump8 macro to simplify code and improve clarity.

Suggested-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Cc: Phil Reid <preid@xxxxxxxxxxxxxxxxx>
Signed-off-by: William Breathitt Gray <vilhelm.gray@xxxxxxxxx>
---
drivers/gpio/gpio-74x164.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/gpio/gpio-74x164.c b/drivers/gpio/gpio-74x164.c
index fb7b620763a2..e43a6de3b6eb 100644
--- a/drivers/gpio/gpio-74x164.c
+++ b/drivers/gpio/gpio-74x164.c
@@ -9,6 +9,7 @@
* published by the Free Software Foundation.
*/

+#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/spi/spi.h>
@@ -75,20 +76,19 @@ static void gen_74x164_set_multiple(struct gpio_chip *gc, unsigned long *mask,
unsigned long *bits)
{
struct gen_74x164_chip *chip = gpiochip_get_data(gc);
- unsigned int i, idx, shift;
- u8 bank, bankmask;
+ unsigned int offset;
+ unsigned long bankmask;
+ const unsigned int ngpio = chip->registers * 8;
+ size_t bank;
+ unsigned int bitmask;

mutex_lock(&chip->lock);
- for (i = 0, bank = chip->registers - 1; i < chip->registers;
- i++, bank--) {
- idx = i / sizeof(*mask);
- shift = i % sizeof(*mask) * BITS_PER_BYTE;
- bankmask = mask[idx] >> shift;
- if (!bankmask)
- continue;
+ for_each_set_clump8(offset, bankmask, mask, ngpio) {
+ bank = (chip->registers - 1) - (offset / 8);
+ bitmask = bitmap_get_value8(bits, ngpio, offset) & bankmask;

chip->buffer[bank] &= ~bankmask;
- chip->buffer[bank] |= bankmask & (bits[idx] >> shift);
+ chip->buffer[bank] |= bitmask;
}
__gen_74x164_write_config(chip);
mutex_unlock(&chip->lock);
--
2.21.0