[PATCH v3] i2c: rcar_i2c: Fix i2c read/write errors

Lad Prabhakar prabhakar.mahadev-lad.rj at bp.renesas.com
Wed Sep 30 14:24:12 CEST 2020


commit 7c8f821e ("i2c: rcar_i2c: Set the slave address from
rcar_i2c_xfer") blindly called rcar_i2c_set_addr() with read argument
always set to 1 during xfer which introduced read/write errors, whereas
earlier rcar_i2c_read_common() called rcar_i2c_set_addr() with read set to
1 and rcar_i2c_write_common() called rcar_i2c_set_addr() with read set 0.

Fixes: 7c8f821e ("i2c: rcar_i2c: Set the slave address from rcar_i2c_xfer")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj at bp.renesas.com>
---
v2->v3
* Made sure value of read is ether 0/1 as pointed by Marek

v1->v2
* Incorporated suggestion from Heiko

v1:
 https://patchwork.ozlabs.org/project/uboot/patch/
 20200921163353.5540-1-prabhakar.mahadev-lad.rj at bp.renesas.com/

Without this patch below errors are seen:
 => i2c probe
Valid chip addresses: 34 47 68
=> i2c md 0x47 0 100
Error reading the chip: -110
=> i2c mw 0x47 0x0a 0x06
Error writing the chip: -110
=>
---
 drivers/i2c/rcar_i2c.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/rcar_i2c.c b/drivers/i2c/rcar_i2c.c
index 4267bbfa5a..663c342cd8 100644
--- a/drivers/i2c/rcar_i2c.c
+++ b/drivers/i2c/rcar_i2c.c
@@ -211,7 +211,7 @@ static int rcar_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs)
 	int ret;
 
 	for (; nmsgs > 0; nmsgs--, msg++) {
-		ret = rcar_i2c_set_addr(dev, msg->addr, 1);
+		ret = rcar_i2c_set_addr(dev, msg->addr, !!(msg->flags & I2C_M_RD));
 		if (ret)
 			return ret;
 
-- 
2.17.1



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