backlight: qcom-wled: Pass number of elements to read to read_u32_array

[ 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@somainline.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20211115203459.1634079-3-marijn.suijten@somainline.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index 8a42ed89c59c9698998bb818c3a76eb4b17d3f44..d413b913fef3283a760907941ed703b5df2c0ef3 100644 (file)
--- 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) {