gpio: ws16c48: utilize for_each_set_clump8 macro

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

Link: http://lkml.kernel.org/r/7a0d2c964e7f2d289b16c63ff6b06fc1f4c50d4d.1570641097.git.vilhelm.gray@gmail.com
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Cc: Morten Hein Tiljeset <morten.tiljeset@prevas.dk>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/gpio/gpio-ws16c48.c b/drivers/gpio/gpio-ws16c48.c
index fe456be..cb510df 100644 (file)
--- a/drivers/gpio/gpio-ws16c48.c
+++ b/drivers/gpio/gpio-ws16c48.c
@@ -129,42 +129,19 @@ 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;
@@ -198,39 +175,29 @@ 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;
        }
 }