[PATCH v2 0/3] Fixes for the mcp2221 HID-to-I2C-bridge driver

From: Enrik Berkhan
Date: Thu Nov 03 2022 - 18:27:34 EST


In this patch series are fixes for issues I found during recent tests of
an MCP2221 board.

- you can confuse the kernel driver when using the chip from user mode
via /dev/hidrawX, typically leading to a NULL pointer dereference in
the driver's HID raw event handler

- the driver needs > 15s to initialize because the HID raw handling is
not enabled during initialization of the GPIO part

- the rxbuf pointer can become invalid or even stale if the device would
send unsolicited reports

Changes in v2:

- removed: data shared with the bottom half code is not protected from
concurrent access

Feedback if this is actually needed or not would be appreciated.

- rebased on linux-hid/for-6.2/mcp2221

Enrik Berkhan (3):
HID: mcp2221: don't connect hidraw
HID: mcp2221: enable HID I/O during GPIO probe
HID: mcp2221: avoid stale rxbuf pointer

drivers/hid/hid-mcp2221.c | 51 +++++++++++++++++++++++++++++++--------
1 file changed, 41 insertions(+), 10 deletions(-)

base-commit: 3d74c9eca1a2bda03e45f18d13154ac3e0dfba85
--
2.34.1