regmap: irq: add chip option mask_writeonly

Some irq controllers have writeonly/multipurpose register layouts. In
those cases we read invalid data back. Here we add the option
mask_writeonly as masking option.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c
index c4a1eadb..429ca8e 100644
--- a/drivers/base/regmap/regmap-irq.c
+++ b/drivers/base/regmap/regmap-irq.c
@@ -60,6 +60,16 @@
 	mutex_lock(&d->lock);
 }
 
+static int regmap_irq_update_bits(struct regmap_irq_chip_data *d,
+				  unsigned int reg, unsigned int mask,
+				  unsigned int val)
+{
+	if (d->chip->mask_writeonly)
+		return regmap_write_bits(d->map, reg, mask, val);
+	else
+		return regmap_update_bits(d->map, reg, mask, val);
+}
+
 static void regmap_irq_sync_unlock(struct irq_data *data)
 {
 	struct regmap_irq_chip_data *d = irq_data_get_irq_chip_data(data);
@@ -84,11 +94,11 @@
 		reg = d->chip->mask_base +
 			(i * map->reg_stride * d->irq_reg_stride);
 		if (d->chip->mask_invert) {
-			ret = regmap_update_bits(d->map, reg,
+			ret = regmap_irq_update_bits(d, reg,
 					 d->mask_buf_def[i], ~d->mask_buf[i]);
 		} else if (d->chip->unmask_base) {
 			/* set mask with mask_base register */
-			ret = regmap_update_bits(d->map, reg,
+			ret = regmap_irq_update_bits(d, reg,
 					d->mask_buf_def[i], ~d->mask_buf[i]);
 			if (ret < 0)
 				dev_err(d->map->dev,
@@ -97,12 +107,12 @@
 			unmask_offset = d->chip->unmask_base -
 							d->chip->mask_base;
 			/* clear mask with unmask_base register */
-			ret = regmap_update_bits(d->map,
+			ret = regmap_irq_update_bits(d,
 					reg + unmask_offset,
 					d->mask_buf_def[i],
 					d->mask_buf[i]);
 		} else {
-			ret = regmap_update_bits(d->map, reg,
+			ret = regmap_irq_update_bits(d, reg,
 					 d->mask_buf_def[i], d->mask_buf[i]);
 		}
 		if (ret != 0)
@@ -113,11 +123,11 @@
 			(i * map->reg_stride * d->irq_reg_stride);
 		if (d->wake_buf) {
 			if (d->chip->wake_invert)
-				ret = regmap_update_bits(d->map, reg,
+				ret = regmap_irq_update_bits(d, reg,
 							 d->mask_buf_def[i],
 							 ~d->wake_buf[i]);
 			else
-				ret = regmap_update_bits(d->map, reg,
+				ret = regmap_irq_update_bits(d, reg,
 							 d->mask_buf_def[i],
 							 d->wake_buf[i]);
 			if (ret != 0)
@@ -153,10 +163,10 @@
 		reg = d->chip->type_base +
 			(i * map->reg_stride * d->type_reg_stride);
 		if (d->chip->type_invert)
-			ret = regmap_update_bits(d->map, reg,
+			ret = regmap_irq_update_bits(d, reg,
 				d->type_buf_def[i], ~d->type_buf[i]);
 		else
-			ret = regmap_update_bits(d->map, reg,
+			ret = regmap_irq_update_bits(d, reg,
 				d->type_buf_def[i], d->type_buf[i]);
 		if (ret != 0)
 			dev_err(d->map->dev, "Failed to sync type in %x\n",
@@ -519,17 +529,17 @@
 		reg = chip->mask_base +
 			(i * map->reg_stride * d->irq_reg_stride);
 		if (chip->mask_invert)
-			ret = regmap_update_bits(map, reg,
+			ret = regmap_irq_update_bits(d, reg,
 					 d->mask_buf[i], ~d->mask_buf[i]);
 		else if (d->chip->unmask_base) {
 			unmask_offset = d->chip->unmask_base -
 					d->chip->mask_base;
-			ret = regmap_update_bits(d->map,
+			ret = regmap_irq_update_bits(d,
 					reg + unmask_offset,
 					d->mask_buf[i],
 					d->mask_buf[i]);
 		} else
-			ret = regmap_update_bits(map, reg,
+			ret = regmap_irq_update_bits(d, reg,
 					 d->mask_buf[i], d->mask_buf[i]);
 		if (ret != 0) {
 			dev_err(map->dev, "Failed to set masks in 0x%x: %d\n",
@@ -575,11 +585,11 @@
 				(i * map->reg_stride * d->irq_reg_stride);
 
 			if (chip->wake_invert)
-				ret = regmap_update_bits(map, reg,
+				ret = regmap_irq_update_bits(d, reg,
 							 d->mask_buf_def[i],
 							 0);
 			else
-				ret = regmap_update_bits(map, reg,
+				ret = regmap_irq_update_bits(d, reg,
 							 d->mask_buf_def[i],
 							 d->wake_buf[i]);
 			if (ret != 0) {
@@ -603,10 +613,10 @@
 			reg = chip->type_base +
 				(i * map->reg_stride * d->type_reg_stride);
 			if (chip->type_invert)
-				ret = regmap_update_bits(map, reg,
+				ret = regmap_irq_update_bits(d, reg,
 					d->type_buf_def[i], 0xFF);
 			else
-				ret = regmap_update_bits(map, reg,
+				ret = regmap_irq_update_bits(d, reg,
 					d->type_buf_def[i], 0x0);
 			if (ret != 0) {
 				dev_err(map->dev,
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index e886492..400172b 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -884,6 +884,7 @@
  *
  * @status_base: Base status register address.
  * @mask_base:   Base mask register address.
+ * @mask_writeonly: Base mask register is write only.
  * @unmask_base:  Base unmask register address. for chips who have
  *                separate mask and unmask registers
  * @ack_base:    Base ack address. If zero then the chip is clear on read.
@@ -927,6 +928,7 @@
 	unsigned int wake_base;
 	unsigned int type_base;
 	unsigned int irq_reg_stride;
+	bool mask_writeonly:1;
 	bool init_ack_masked:1;
 	bool mask_invert:1;
 	bool use_ack:1;