| Message ID | 20181108134548.31140-1-m.szyprowski@samsung.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Fix common issue in MAX* extcon drivers | expand |
Hi Marek, On 2018년 11월 08일 22:45, Marek Szyprowski wrote: > Hi All > > Most MAX* MUIC drivers unconditionally force UART path during probe. > This approach causes some issues, especially when board is booted with > non-UART cable connected to micro-USB port. For example, when USB cable is > connected, UART TX/RX lines are unconditionally short-circuited to USB > D+/D- lines. This is in turn recognized by a series of serial BREAK > signals and some random characters when USB host tries to perform > enumeration procedure. > > To solve the above issue and keep UART console operational as early as > possible, set UART path only when USB ID reports UART capable cable. > > This patchset fixes following MAX* extcon drivers: 8997, 14577, 77693 > and 77843. > > Tested on following Samsung boards: Trats (8997), Rinato (14577), Trats2 > (77693) and TM2/TM2e (77843). > > Best regards > Marek Szyprowski > Samsung R&D Institute Poland > > > Patch summary: > > Marek Szyprowski (4): > extcon: max77843: Avoid forcing UART path on drive probe > extcon: max77693: Avoid forcing UART path on drive probe > extcon: max14577: Avoid forcing UART path on drive probe > extcon: max8997: Avoid forcing UART path on drive probe > > drivers/extcon/extcon-max14577.c | 15 +++++++++++++-- > drivers/extcon/extcon-max77693.c | 16 ++++++++++++++-- > drivers/extcon/extcon-max77843.c | 18 +++++++++++++++--- > drivers/extcon/extcon-max8997.c | 15 +++++++++++++-- > 4 files changed, 55 insertions(+), 9 deletions(-) > Applied them. Thanks.