On Nov 03 2022, Enrik Berkhan wrote: > The MCP2221 driver should not connect to the hidraw userspace interface, > as it needs exclusive access to the chip. > > If you want to use /dev/hidrawX with the MCP2221, you need to avoid > binding this driver to the device and use the hid generic driver instead > (e.g. using udev rules). > > Signed-off-by: Enrik Berkhan <Enrik.Berkhan@xxxxxxx> > --- Given the NULL pointer deference report at https://lore.kernel.org/all/79152feb-bcbc-9e3e-e776-13170ae4ef40@xxxxxxxx/ I have added: Reported-by: Sven Zühlsdorf <sven.zuehlsdorf@xxxxxxxx> And applied this one only in the series in for-6.2/upstream-fixes. Before applying the rest I'd rather have some external reviews of this series. Cheers, Benjamin > drivers/hid/hid-mcp2221.c | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/drivers/hid/hid-mcp2221.c b/drivers/hid/hid-mcp2221.c > index 5886543b17f3..e61dd039354b 100644 > --- a/drivers/hid/hid-mcp2221.c > +++ b/drivers/hid/hid-mcp2221.c > @@ -1110,12 +1110,19 @@ static int mcp2221_probe(struct hid_device *hdev, > return ret; > } > > - ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW); > + /* > + * This driver uses the .raw_event callback and therefore does not need any > + * HID_CONNECT_xxx flags. > + */ > + ret = hid_hw_start(hdev, 0); > if (ret) { > hid_err(hdev, "can't start hardware\n"); > return ret; > } > > + hid_info(hdev, "USB HID v%x.%02x Device [%s] on %s\n", hdev->version >> 8, > + hdev->version & 0xff, hdev->name, hdev->phys); > + > ret = hid_hw_open(hdev); > if (ret) { > hid_err(hdev, "can't open device\n"); > @@ -1145,8 +1152,7 @@ static int mcp2221_probe(struct hid_device *hdev, > mcp->adapter.retries = 1; > mcp->adapter.dev.parent = &hdev->dev; > snprintf(mcp->adapter.name, sizeof(mcp->adapter.name), > - "MCP2221 usb-i2c bridge on hidraw%d", > - ((struct hidraw *)hdev->hidraw)->minor); > + "MCP2221 usb-i2c bridge"); > > ret = devm_i2c_add_adapter(&hdev->dev, &mcp->adapter); > if (ret) { > -- > 2.34.1 >
