[PATCH 5.10 190/563] backlight: qcom-wled: Pass number of elements to read to read_u32_array

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 16:13:41 EST


From: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>

[ Upstream commit e29e24bdabfeddbf8b1a4ecac1af439a85150438 ]

of_property_read_u32_array takes the number of elements to read as last
argument. This does not always need to be 4 (sizeof(u32)) but should
instead be the size of the array in DT as read just above with
of_property_count_elems_of_size.

To not make such an error go unnoticed again the driver now bails
accordingly when of_property_read_u32_array returns an error.
Surprisingly the indentation of newlined arguments is lining up again
after prepending `rc = `.

Fixes: 775d2ffb4af6 ("backlight: qcom-wled: Restructure the driver for WLED3")
Signed-off-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxxx>
Reviewed-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>
Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20211115203459.1634079-3-marijn.suijten@xxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/video/backlight/qcom-wled.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index 2c4290f082025..92df5a9f6ae51 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -1535,10 +1535,15 @@ static int wled_configure(struct wled *wled)
return -EINVAL;
}

- of_property_read_u32_array(dev->of_node,
+ rc = of_property_read_u32_array(dev->of_node,
"qcom,enabled-strings",
wled->cfg.enabled_strings,
- sizeof(u32));
+ string_len);
+ if (rc) {
+ dev_err(dev, "Failed to read %d elements from qcom,enabled-strings: %d\n",
+ string_len, rc);
+ return rc;
+ }

for (i = 0; i < string_len; ++i) {
if (wled->cfg.enabled_strings[i] >= wled->max_string_count) {
--
2.34.1