[RESEND PATCH v4 8/8] gpio: pcie-idio-24: Utilize for_each_set_clump macro

From: William Breathitt Gray
Date: Mon Oct 01 2018 - 21:16:16 EST


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

Signed-off-by: William Breathitt Gray <vilhelm.gray@xxxxxxxxx>
---
drivers/gpio/gpio-pcie-idio-24.c | 102 +++++++++++--------------------
1 file changed, 36 insertions(+), 66 deletions(-)

diff --git a/drivers/gpio/gpio-pcie-idio-24.c b/drivers/gpio/gpio-pcie-idio-24.c
index f953541e7890..b4d300338a05 100644
--- a/drivers/gpio/gpio-pcie-idio-24.c
+++ b/drivers/gpio/gpio-pcie-idio-24.c
@@ -199,41 +199,21 @@ static int idio_24_gpio_get_multiple(struct gpio_chip *chip,
{
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
size_t i;
- 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 long port_state;
+ size_t word;
+ unsigned int offset;
void __iomem *ports[] = {
&idio24gpio->reg->out0_7, &idio24gpio->reg->out8_15,
&idio24gpio->reg->out16_23, &idio24gpio->reg->in0_7,
&idio24gpio->reg->in8_15, &idio24gpio->reg->in16_23,
};
+ const size_t num_ports = ARRAY_SIZE(ports) + 1;
+ unsigned long port_state;
const unsigned long out_mode_mask = BIT(1);

/* 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) + 1; 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;
- }
-
+ for_each_set_clump(i, word, offset, mask, num_ports, 8) {
/* read bits from current gpio port (port 6 is TTL GPIO) */
if (i < 6)
port_state = ioread8(ports[i]);
@@ -243,7 +223,7 @@ static int idio_24_gpio_get_multiple(struct gpio_chip *chip,
port_state = ioread8(&idio24gpio->reg->ttl_in0_7);

/* store acquired bits at respective bits array offset */
- bits[word_index] |= port_state << word_offset;
+ bits[word] |= port_state << offset;
}

return 0;
@@ -295,58 +275,48 @@ static void idio_24_gpio_set_multiple(struct gpio_chip *chip,
{
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
size_t i;
- unsigned long bits_offset;
- unsigned long gpio_mask;
- const unsigned int gpio_reg_size = 8;
- const unsigned long port_mask = GENMASK(gpio_reg_size, 0);
- unsigned long flags;
- unsigned int out_state;
+ size_t word;
+ unsigned int offset;
void __iomem *ports[] = {
&idio24gpio->reg->out0_7, &idio24gpio->reg->out8_15,
&idio24gpio->reg->out16_23
};
+ const size_t num_ports = ARRAY_SIZE(ports) + 1;
+ unsigned int iomask;
+ unsigned int bitmask;
+ unsigned long flags;
const unsigned long out_mode_mask = BIT(1);
- const unsigned int ttl_offset = 48;
- const size_t ttl_i = BIT_WORD(ttl_offset);
- const unsigned int word_offset = ttl_offset % BITS_PER_LONG;
- const unsigned long ttl_mask = (mask[ttl_i] >> word_offset) & port_mask;
- const unsigned long ttl_bits = (bits[ttl_i] >> word_offset) & ttl_mask;
-
- /* set bits are processed 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;
-
- /* check if any set bits for current port */
- gpio_mask = (*mask >> bits_offset) & port_mask;
- if (!gpio_mask) {
- /* no set bits for this port so move on to next port */
+ unsigned int out_state;
+
+ for_each_set_clump(i, word, offset, mask, num_ports, 8) {
+ iomask = mask[word] >> offset;
+ bitmask = iomask & (bits[word] >> offset);
+
+ raw_spin_lock_irqsave(&idio24gpio->lock, flags);
+
+ /* read bits from current gpio port (port 6 is TTL GPIO) */
+ if (i < 6) {
+ out_state = ioread8(ports[i]) & ~iomask;
+ } else if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask) {
+ out_state = ioread8(&idio24gpio->reg->ttl_out0_7);
+ } else {
+ /* skip TTL GPIO if set for input */
+ raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
continue;
}

- raw_spin_lock_irqsave(&idio24gpio->lock, flags);
+ /* set requested bit states */
+ out_state &= ~iomask;
+ out_state |= bitmask;

- /* process output lines */
- out_state = ioread8(ports[i]) & ~gpio_mask;
- out_state |= (*bits >> bits_offset) & gpio_mask;
- iowrite8(out_state, ports[i]);
+ /* write bits for current gpio port (port 6 is TTL GPIO) */
+ if (i < 6)
+ iowrite8(out_state, ports[i]);
+ else
+ iowrite8(out_state, &idio24gpio->reg->ttl_out0_7);

raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
}
-
- /* check if setting TTL lines and if they are in output mode */
- if (!ttl_mask || !(ioread8(&idio24gpio->reg->ctl) & out_mode_mask))
- return;
-
- /* handle TTL output */
- raw_spin_lock_irqsave(&idio24gpio->lock, flags);
-
- /* process output lines */
- out_state = ioread8(&idio24gpio->reg->ttl_out0_7) & ~ttl_mask;
- out_state |= ttl_bits;
- iowrite8(out_state, &idio24gpio->reg->ttl_out0_7);
-
- raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
}

static void idio_24_irq_ack(struct irq_data *data)
--
2.19.0