From 2e84a5e5374232e6f356ce5c079a5658d7e4af2c Mon Sep 17 00:00:00 2001 From: Johan Adolfsson Date: Tue, 17 Jun 2025 12:23:54 +0200 Subject: [PATCH] leds: leds-lp50xx: Handle reg to get correct multi_index mc_subled used for multi_index needs well defined array indexes, to guarantee the desired result, use reg for that. If devicetree child nodes is processed in random or reverse order you may end up with multi_index "blue green red" instead of the expected "red green blue". If user space apps uses multi_index to deduce how to control the leds they would most likely be broken without this patch if devicetree processing is reversed (which it appears to be). arch/arm/boot/dts/aspeed/aspeed-bmc-facebook-fuji.dts has reg set but I don't see how it can have worked without this change. If reg is not set, an error is returned, If reg is out of range, an error is returned. reg within led child nodes starts with 0, to map to the iout in each bank. Signed-off-by: Johan Adolfsson Reviewed-by: Jacek Anaszewski Link: https://lore.kernel.org/r/20250617-led-fix-v7-1-cdbe8efc88fa@axis.com Signed-off-by: Lee Jones --- drivers/leds/leds-lp50xx.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/leds/leds-lp50xx.c b/drivers/leds/leds-lp50xx.c index 02cb1565a9fb6..94f8ef6b482c9 100644 --- a/drivers/leds/leds-lp50xx.c +++ b/drivers/leds/leds-lp50xx.c @@ -476,6 +476,7 @@ static int lp50xx_probe_dt(struct lp50xx *priv) return -ENOMEM; fwnode_for_each_child_node(child, led_node) { + int multi_index; ret = fwnode_property_read_u32(led_node, "color", &color_id); if (ret) { @@ -483,8 +484,16 @@ static int lp50xx_probe_dt(struct lp50xx *priv) dev_err(priv->dev, "Cannot read color\n"); return ret; } + ret = fwnode_property_read_u32(led_node, "reg", &multi_index); + if (ret != 0) { + dev_err(priv->dev, "reg must be set\n"); + return -EINVAL; + } else if (multi_index >= LP50XX_LEDS_PER_MODULE) { + dev_err(priv->dev, "reg %i out of range\n", multi_index); + return -EINVAL; + } - mc_led_info[num_colors].color_index = color_id; + mc_led_info[multi_index].color_index = color_id; num_colors++; } -- 2.47.3