[PATCH] i2c: designware_i2c: remove apparently redundant read of 'i2c, speeds' DT property

Rasmus Villemoes rasmus.villemoes at prevas.dk
Fri Mar 24 09:09:22 CET 2023

This code first figures out if there is an i2c,speeds property, if so
its size in u32s, and then reads the value into the local speeds[]
array. Both 'size' and 'speeds' are completely unused thereafter.

It's not at all clear what this is supposed to do. Of course, it could
be seen as a sanity check that the DT node does have an i2c,speeds
property with an appropriate number of elements, but for that one
wouldn't actually need to read it into speeds[]. Also, I can't find
anywhere else in the U-Boot code which makes use of values from that
property (this is is the only C code referencing "i2c,speeds"), so it
seems pointless to insist that it's there.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes at prevas.dk>
 drivers/i2c/designware_i2c_pci.c | 14 --------------
 1 file changed, 14 deletions(-)

diff --git a/drivers/i2c/designware_i2c_pci.c b/drivers/i2c/designware_i2c_pci.c
index 46c2545f21..28495a3f42 100644
--- a/drivers/i2c/designware_i2c_pci.c
+++ b/drivers/i2c/designware_i2c_pci.c
@@ -147,9 +147,7 @@ static int dw_i2c_acpi_fill_ssdt(const struct udevice *dev,
 	struct dw_i2c_speed_config config;
 	char path[ACPI_PATH_MAX];
-	u32 speeds[4];
 	uint speed;
-	int size;
 	int ret;
 	/* If no device-tree node, ignore this since we assume it isn't used */
@@ -160,18 +158,6 @@ static int dw_i2c_acpi_fill_ssdt(const struct udevice *dev,
 	if (ret)
 		return log_msg_ret("path", ret);
-	size = dev_read_size(dev, "i2c,speeds");
-	if (size < 0)
-		return log_msg_ret("i2c,speeds", -EINVAL);
-	size /= sizeof(u32);
-	if (size > ARRAY_SIZE(speeds))
-		return log_msg_ret("array", -E2BIG);
-	ret = dev_read_u32_array(dev, "i2c,speeds", speeds, size);
-	if (ret)
-		return log_msg_ret("read", -E2BIG);
 	speed = dev_read_u32_default(dev, "clock-frequency", 100000);
 	acpigen_write_scope(ctx, path);
 	ret = dw_i2c_gen_speed_config(dev, speed, &config);

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