From: Luca Weiss <luca.weiss@xxxxxxxxxxxxx>
commit 4f83cae0edb2b13aabb82e8a4852092844d320aa upstream.
Some FSA4480-compatible chips like the OCP96011 used on Fairphone 5
return 0x00 from the CHIP_ID register. Handle that gracefully and only
fail probe when the I2C read has failed.
With this the dev_dbg will print 0 but otherwise continue working.
[ 0.251581] fsa4480 1-0042: Found FSA4480 v0.0 (Vendor ID = 0)
Cc: stable@xxxxxxxxxxxxxxx
Fixes: e885f5f1f2b4 ("usb: typec: fsa4480: Check if the chip is really there")
Signed-off-by: Luca Weiss <luca.weiss@xxxxxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Reviewed-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240818-fsa4480-chipid-fix-v1-1-17c239435cf7@xxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/typec/mux/fsa4480.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/typec/mux/fsa4480.c b/drivers/usb/typec/mux/fsa4480.c
index cd235339834b..f71dba8bf07c 100644
--- a/drivers/usb/typec/mux/fsa4480.c
+++ b/drivers/usb/typec/mux/fsa4480.c
@@ -274,7 +274,7 @@ static int fsa4480_probe(struct i2c_client *client)
return dev_err_probe(dev, PTR_ERR(fsa->regmap), "failed to initialize regmap\n");
ret = regmap_read(fsa->regmap, FSA4480_DEVICE_ID, &val);
- if (ret || !val)
+ if (ret)
return dev_err_probe(dev, -ENODEV, "FSA4480 not found\n");
dev_dbg(dev, "Found FSA4480 v%lu.%lu (Vendor ID = %lu)\n",
--
2.46.0
Patches currently in stable-queue which might be from luca.weiss@xxxxxxxxxxxxx are
queue-6.10/usb-typec-fsa4480-relax-chip_id-check.patch
