ucsi_ccg: Check DEV_INT bit only when starting CCG4
authorSing-Han Chen <singhanc@nvidia.com>
Wed, 12 Jan 2022 09:41:43 +0000 (17:41 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 1 Feb 2022 16:25:41 +0000 (17:25 +0100)
commit3921d081c9c395e7ce63d0081276070c2e6bf64c
treeb7d9a9b4076e0b9481455ec0ffbabafbaef33b14
parent598a884c772c9a34b486d2f16e36dc98e2112727
ucsi_ccg: Check DEV_INT bit only when starting CCG4

commit 825911492eb15bf8bb7fb94bc0c0421fe7a6327d upstream.

CCGx clears Bit 0:Device Interrupt in the INTR_REG
if CCGx is reset successfully. However, there might
be a chance that other bits in INTR_REG are not
cleared due to internal data queued in PPM. This case
misleads the driver that CCGx reset failed.

The commit checks bit 0 in INTR_REG and ignores other
bits. The ucsi driver would reset PPM later.

Fixes: 247c554a14aa ("usb: typec: ucsi: add support for Cypress CCGx")
Cc: stable@vger.kernel.org
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Sing-Han Chen <singhanc@nvidia.com>
Signed-off-by: Wayne Chang <waynec@nvidia.com>
Link: https://lore.kernel.org/r/20220112094143.628610-1-waynec@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/typec/ucsi/ucsi_ccg.c