On Sun Aug 18, 2024 at 10:21 PM CEST, Luca Weiss wrote: > 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) Short appendix: just checked the OCP96011 datasheet and it does mention register 00H being "Device ID" and "Reset Value" being 0x00 so that's expected behavior on this specific chip. Regards Luca > > Cc: stable@xxxxxxxxxxxxxxx > Fixes: e885f5f1f2b4 ("usb: typec: fsa4480: Check if the chip is really there") > Signed-off-by: Luca Weiss <luca.weiss@xxxxxxxxxxxxx> > --- > 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", > > --- > base-commit: ccdbf91fdf5a71881ef32b41797382c4edd6f670 > change-id: 20240818-fsa4480-chipid-fix-2c7cf5810135 > > Best regards,