[PATCH] drm: bridge: anx7625: Use of_property_read_variable_u8_array()

From: Rob Herring (Arm)
Date: Wed Jul 31 2024 - 16:15:20 EST


There's no need to get the length of an DT array property before
parsing the array. of_property_read_variable_u8_array() takes a minimum
and maximum length and returns the actual length (or error code).

This is part of a larger effort to remove callers of of_get_property()
and similar functions. of_get_property() leaks the DT property data
pointer which is a problem for dynamically allocated nodes which may
be freed.

Signed-off-by: Rob Herring (Arm) <robh@xxxxxxxxxx>
---
drivers/gpu/drm/bridge/analogix/anx7625.c | 22 ++++++----------------
1 file changed, 6 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 88e4aa5830f3..a2e9bb485c36 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -1647,25 +1647,15 @@ static int anx7625_get_swing_setting(struct device *dev,
{
int num_regs;

- if (of_get_property(dev->of_node,
- "analogix,lane0-swing", &num_regs)) {
- if (num_regs > DP_TX_SWING_REG_CNT)
- num_regs = DP_TX_SWING_REG_CNT;
-
+ num_regs = of_property_read_variable_u8_array(dev->of_node, "analogix,lane0-swing",
+ pdata->lane0_reg_data, 1, DP_TX_SWING_REG_CNT);
+ if (num_regs > 0)
pdata->dp_lane0_swing_reg_cnt = num_regs;
- of_property_read_u8_array(dev->of_node, "analogix,lane0-swing",
- pdata->lane0_reg_data, num_regs);
- }
-
- if (of_get_property(dev->of_node,
- "analogix,lane1-swing", &num_regs)) {
- if (num_regs > DP_TX_SWING_REG_CNT)
- num_regs = DP_TX_SWING_REG_CNT;

+ num_regs = of_property_read_variable_u8_array(dev->of_node, "analogix,lane1-swing",
+ pdata->lane1_reg_data, 1, DP_TX_SWING_REG_CNT);
+ if (num_regs > 0)
pdata->dp_lane1_swing_reg_cnt = num_regs;
- of_property_read_u8_array(dev->of_node, "analogix,lane1-swing",
- pdata->lane1_reg_data, num_regs);
- }

return 0;
}
--
2.43.0