regmap: Only send a single buffer for async I/O if writing one register
Extend the interface for async I/O by allowing the value buffer to be
omitted and sending the value as part of the register buffer, minimising
the number of separate hardware operations required.
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index a975a60..d0ce2fef 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -1157,18 +1157,23 @@
/* If the caller supplied the value we can use it safely. */
memcpy(async->work_buf, map->work_buf, map->format.pad_bytes +
map->format.reg_bytes + map->format.val_bytes);
- if (val == work_val)
- val = async->work_buf + map->format.pad_bytes +
- map->format.reg_bytes;
spin_lock_irqsave(&map->async_lock, flags);
list_add_tail(&async->list, &map->async_list);
spin_unlock_irqrestore(&map->async_lock, flags);
- ret = map->bus->async_write(map->bus_context, async->work_buf,
- map->format.reg_bytes +
- map->format.pad_bytes,
- val, val_len, async);
+ if (val != work_val)
+ ret = map->bus->async_write(map->bus_context,
+ async->work_buf,
+ map->format.reg_bytes +
+ map->format.pad_bytes,
+ val, val_len, async);
+ else
+ ret = map->bus->async_write(map->bus_context,
+ async->work_buf,
+ map->format.reg_bytes +
+ map->format.pad_bytes +
+ val_len, NULL, 0, async);
if (ret != 0) {
dev_err(map->dev, "Failed to schedule write: %d\n",