On 23-08-16, Fabio Estevam wrote:
From: Marco Felsch m.felsch@pengutronix.de
According the "USB Type-C Port Controller Interface Specification v2.0" the TCPC sets the fault status register bit-7 (AllRegistersResetToDefault) once the registers have been reset to their default values.
This triggers an alert(-irq) on PTN5110 devices albeit we do mask the fault-irq, which may cause a kernel hang. Fix this generically by writing a one to the corresponding bit-7.
Cc: stable@vger.kernel.org Fixes: 74e656d6b055 ("staging: typec: Type-C Port Controller Interface driver (tcpci)") Reported-by: Angus Ainslie (Purism) angus@akkea.ca Closes: https://lore.kernel.org/all/20190508002749.14816-2-angus@akkea.ca/ Reported-by: Christian Bach christian.bach@scs.ch Closes: https://lore.kernel.org/regressions/ZR0P278MB07737E5F1D48632897D51AC3EB329@Z... Signed-off-by: Marco Felsch m.felsch@pengutronix.de Signed-off-by: Fabio Estevam festevam@denx.de
Changes since v2:
- Submitted it as a standalone patch.
- Explain that it may cause a kernel hang.
- Fixed typos in the commit log. (Guenter)
- Check the tcpci_write16() return value. (Guenter)
- Write to TCPC_FAULT_STATUS unconditionally. (Guenter)
- Added Fixes, Reported-by and Closes tags.
- CCed stable
thanks for the work Fabio :)
Regards, Marco
drivers/usb/typec/tcpm/tcpci.c | 4 ++++ include/linux/usb/tcpci.h | 1 + 2 files changed, 5 insertions(+)
diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c index fc708c289a73..0ee3e6e29bb1 100644 --- a/drivers/usb/typec/tcpm/tcpci.c +++ b/drivers/usb/typec/tcpm/tcpci.c @@ -602,6 +602,10 @@ static int tcpci_init(struct tcpc_dev *tcpc) if (time_after(jiffies, timeout)) return -ETIMEDOUT;
- ret = tcpci_write16(tcpci, TCPC_FAULT_STATUS, TCPC_FAULT_STATUS_ALL_REG_RST_TO_DEFAULT);
- if (ret < 0)
return ret;- /* Handle vendor init */ if (tcpci->data->init) { ret = tcpci->data->init(tcpci, tcpci->data);
diff --git a/include/linux/usb/tcpci.h b/include/linux/usb/tcpci.h index 85e95a3251d3..83376473ac76 100644 --- a/include/linux/usb/tcpci.h +++ b/include/linux/usb/tcpci.h @@ -103,6 +103,7 @@ #define TCPC_POWER_STATUS_SINKING_VBUS BIT(0) #define TCPC_FAULT_STATUS 0x1f +#define TCPC_FAULT_STATUS_ALL_REG_RST_TO_DEFAULT BIT(7) #define TCPC_ALERT_EXTENDED 0x21 -- 2.34.1