regmap: irq: Allow using zero value for ack_base

In some cases, clear interrupt register may be at address 0.
This patch allows to use such configurations by adding additional
configuration bit to indicate this.

[With doc fix from Levente Kurusa <levex@linux.com> -- broonie]

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c
index 763c60d3d277..82692068d3cb 100644
--- a/drivers/base/regmap/regmap-irq.c
+++ b/drivers/base/regmap/regmap-irq.c
@@ -113,7 +113,7 @@ static void regmap_irq_sync_unlock(struct irq_data *data)
                  * OR if there is masked interrupt which hasn't been Acked,
                  * it'll be ignored in irq handler, then may introduce irq storm
                  */
-                if (d->mask_buf[i] && d->chip->ack_base) {
+                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]);
@@ -271,7 +271,7 @@ static irqreturn_t regmap_irq_thread(int irq, void *d)
         for (i = 0; i < data->chip->num_regs; i++) {
                 data->status_buf[i] &= ~data->mask_buf[i];
 
-                if (data->status_buf[i] && chip->ack_base) {
+                if (data->status_buf[i] && (chip->ack_base || chip->use_ack)) {
                         reg = chip->ack_base +
                                 (i * map->reg_stride * data->irq_reg_stride);
                         ret = regmap_write(map, reg, data->status_buf[i]);
@@ -448,7 +448,7 @@ int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
                         goto err_alloc;
                 }
 
-                if (d->status_buf[i] && chip->ack_base) {
+                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,