[PATCH v14 06/11] gpio: ws16c48: Utilize for_each_set_clump8 macro

William Breathitt Gray
2019-03-29T03:05:48Z

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@linaro.org>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
---
drivers/gpio/gpio-ws16c48.c | 73 ++++++++++---------------------------
1 file changed, 20 insertions(+), 53 deletions(-)

diff --git a/drivers/gpio/gpio-ws16c48.c b/drivers/gpio/gpio-ws16c48.c
index 5cf3697bfb15..ee30417d6394 100644
--- a/drivers/gpio/gpio-ws16c48.c
+++ b/drivers/gpio/gpio-ws16c48.c
@@ -134,42 +134,19 @@ static int ws16c48_gpio_get_multiple(struct gpio_chip *chip,
unsigned long *mask, unsigned long *bits)
{
struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
- const unsigned int gpio_reg_size = 8;
- size_t i;
- const size_t num_ports = chip->ngpio / gpio_reg_size;
- 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 offset;
+ unsigned long gpio_mask;
+ 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 < num_ports; i++) {
- /* gpio offset in bits array */
- bits_offset = i * gpio_reg_size;
+ for_each_set_clump8(offset, gpio_mask, mask, chip->ngpio) {
+ port_addr = ws16c48gpio->base + 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(ws16c48gpio->base + i);
-
- /* store acquired bits at respective bits array offset */
- bits[word_index] |= (port_state << word_offset) & word_mask;
+ bitmap_set_value8(bits, port_state, offset);
}

return 0;
@@ -203,39 +180,29 @@ static void ws16c48_gpio_set_multiple(struct gpio_chip *chip,
unsigned long *mask, unsigned long *bits)
{
struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
- unsigned int i;
- const unsigned int gpio_reg_size = 8;
- unsigned int port;
- unsigned int iomask;
- unsigned int bitmask;
+ unsigned long offset;
+ unsigned long gpio_mask;
+ size_t index;
+ unsigned int port_addr;
+ unsigned long 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;
+ for_each_set_clump8(offset, gpio_mask, mask, chip->ngpio) {
+ index = offset / 8;
+ port_addr = ws16c48gpio->base + index;

/* mask out GPIO configured for input */
- iomask = mask[BIT_WORD(i)] & ~ws16c48gpio->io_state[port];
- bitmask = iomask & bits[BIT_WORD(i)];
+ gpio_mask &= ~ws16c48gpio->io_state[index];
+ bitmask = bitmap_get_value8(bits, offset) & gpio_mask;

raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);

/* update output state data and set device gpio register */
- ws16c48gpio->out_state[port] &= ~iomask;
- ws16c48gpio->out_state[port] |= bitmask;
- outb(ws16c48gpio->out_state[port], ws16c48gpio->base + port);
+ ws16c48gpio->out_state[index] &= ~gpio_mask;
+ ws16c48gpio->out_state[index] |= bitmask;
+ outb(ws16c48gpio->out_state[index], port_addr);

raw_spin_unlock_irqrestore(&ws16c48gpio->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