[PATCH v2 2/2] regmap: stop splitting writes to non incrementing registers

From: Ben Whitten
Date: Sat Jan 18 2020 - 15:57:01 EST


When writing to non incrementing registers we should not split
the writes in any way, writing in one transaction.

Signed-off-by: Ben Whitten <ben.whitten@xxxxxxxxx>
---
drivers/base/regmap/regmap.c | 38 +++++++++++++++++++++---------------
1 file changed, 22 insertions(+), 16 deletions(-)

diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 59f911e57719..d0dbf0ffd70f 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -1528,24 +1528,30 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg,
int win_offset = (reg - range->range_min) % range->window_len;
int win_residue = range->window_len - win_offset;

- /* If the write goes beyond the end of the window split it */
- while (val_num > win_residue) {
- dev_dbg(map->dev, "Writing window %d/%zu\n",
- win_residue, val_len / map->format.val_bytes);
- ret = _regmap_raw_write_impl(map, reg, val,
- win_residue *
- map->format.val_bytes);
- if (ret != 0)
- return ret;
+ if (!regmap_writeable_noinc(map, reg)) {
+ /* If the write goes beyond the end of the window
+ * split it */
+ while (val_num > win_residue) {
+ dev_dbg(map->dev, "Writing window %d/%zu\n",
+ win_residue,
+ val_len / map->format.val_bytes);
+ ret = _regmap_raw_write_impl(map, reg, val,
+ win_residue *
+ map->format.val_bytes);
+ if (ret != 0)
+ return ret;

- reg += win_residue;
- val_num -= win_residue;
- val += win_residue * map->format.val_bytes;
- val_len -= win_residue * map->format.val_bytes;
+ reg += win_residue;
+ val_num -= win_residue;
+ val += win_residue * map->format.val_bytes;
+ val_len -= win_residue * map->format.val_bytes;

- win_offset = (reg - range->range_min) %
- range->window_len;
- win_residue = range->window_len - win_offset;
+ win_offset = (reg - range->range_min) %
+ range->window_len;
+ win_residue = range->window_len - win_offset;
+ }
+ } else {
+ val_num = 1;
}

ret = _regmap_select_page(map, &reg, range, val_num);
--
2.17.1