The process of adding an I2C adapter can invoke I2C accesses on that new adapter (see i2c_detect()).
Ensure we have set the adapter's driver data to avoid null pointer dereferences in the xfer functions during the adapter add.
This has been noted in the past and the same fix proposed but not completed. See: https://lore.kernel.org/lkml/ef597e73-ed71-168e-52af-0d19b03734ac@vigem.de/
Signed-off-by: Hamish Martin hamish.martin@alliedtelesis.co.nz Signed-off-by: Jiri Kosina jkosina@suse.cz Signed-off-by: Sumanth Gavini sumanth.gavini@yahoo.com --- drivers/hid/hid-mcp2221.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hid/hid-mcp2221.c b/drivers/hid/hid-mcp2221.c index de52e9f7bb8c..9973545c1c4b 100644 --- a/drivers/hid/hid-mcp2221.c +++ b/drivers/hid/hid-mcp2221.c @@ -873,12 +873,12 @@ static int mcp2221_probe(struct hid_device *hdev, "MCP2221 usb-i2c bridge on hidraw%d", ((struct hidraw *)hdev->hidraw)->minor);
+ i2c_set_adapdata(&mcp->adapter, mcp); ret = i2c_add_adapter(&mcp->adapter); if (ret) { hid_err(hdev, "can't add usb-i2c adapter: %d\n", ret); goto err_i2c; } - i2c_set_adapdata(&mcp->adapter, mcp);
/* Setup GPIO chip */ mcp->gc = devm_kzalloc(&hdev->dev, sizeof(*mcp->gc), GFP_KERNEL);