regmap: irq: add ack_invert flag for chips using cleared bits as ack

An user will be CSR SiRFSoC ARM chips.
Signed-off-by: Guo Zeng <Guo.Zeng@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/base/regmap/regmap-irq.c

@@ -133,7 +133,11 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
 		if (d->mask_buf[i] && (d->chip->ack_base || d->chip->use_ack)) {
 			reg = d->chip->ack_base +
 				(i * map->reg_stride * d->irq_reg_stride);
-			ret = regmap_write(map, reg, d->mask_buf[i]);
+			/* some chips ack by write 0 */
+			if (d->chip->ack_invert)
+				ret = regmap_write(map, reg, ~d->mask_buf[i]);
+			else
+				ret = regmap_write(map, reg, d->mask_buf[i]);
 			if (ret != 0)
 				dev_err(d->map->dev, "Failed to ack 0x%x: %d\n",
 					reg, ret);
@@ -470,7 +474,11 @@ int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 		if (d->status_buf[i] && (chip->ack_base || chip->use_ack)) {
 			reg = chip->ack_base +
 				(i * map->reg_stride * d->irq_reg_stride);
-			ret = regmap_write(map, reg,
+			if (chip->ack_invert)
+				ret = regmap_write(map, reg,
+					~(d->status_buf[i] & d->mask_buf[i]));
+			else
+				ret = regmap_write(map, reg,
 					d->status_buf[i] & d->mask_buf[i]);
 			if (ret != 0) {
 				dev_err(map->dev, "Failed to ack 0x%x: %d\n",

include/linux/regmap.h

@@ -809,6 +809,7 @@ struct regmap_irq {
  * @init_ack_masked: Ack all masked interrupts once during initalization.
  * @mask_invert: Inverted mask register: cleared bits are masked out.
  * @use_ack:     Use @ack register even if it is zero.
+ * @ack_invert:  Inverted ack register: cleared bits for ack.
  * @wake_invert: Inverted wake register: cleared bits are wake enabled.
  * @runtime_pm:  Hold a runtime PM lock on the device when accessing it.
  *
@@ -829,6 +830,7 @@ struct regmap_irq_chip {
 	bool init_ack_masked:1;
 	bool mask_invert:1;
 	bool use_ack:1;
+	bool ack_invert:1;
 	bool wake_invert:1;
 	bool runtime_pm:1;