| From c0cff0b2390451bc23d873f7507ed4a54732eb34 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Wed, 3 Mar 2021 23:09:31 -0800 |
| Subject: usb: typec: tcpci: Check ROLE_CONTROL while interpreting CC_STATUS |
| |
| From: Badhri Jagan Sridharan <badhri@google.com> |
| |
| [ Upstream commit 19c234a14eafca78e0bc14ffb8be3891096ce147 ] |
| |
| While interpreting CC_STATUS, ROLE_CONTROL has to be read to make |
| sure that CC1/CC2 is not forced presenting Rp/Rd. |
| |
| >From the TCPCI spec: |
| |
| 4.4.5.2 ROLE_CONTROL (Normative): |
| The TCPM shall write B6 (DRP) = 0b and B3..0 (CC1/CC2) if it wishes |
| to control the Rp/Rd directly instead of having the TCPC perform |
| DRP toggling autonomously. When controlling Rp/Rd directly, the |
| TCPM writes to B3..0 (CC1/CC2) each time it wishes to change the |
| CC1/CC2 values. This control is used for TCPM-TCPC implementing |
| Source or Sink only as well as when a connection has been detected |
| via DRP toggling but the TCPM wishes to attempt Try.Src or Try.Snk. |
| |
| Table 4-22. CC_STATUS Register Definition: |
| If (ROLE_CONTROL.CC1 = Rd) or ConnectResult=1) |
| 00b: SNK.Open (Below maximum vRa) |
| 01b: SNK.Default (Above minimum vRd-Connect) |
| 10b: SNK.Power1.5 (Above minimum vRd-Connect) Detects Rp-1.5A |
| 11b: SNK.Power3.0 (Above minimum vRd-Connect) Detects Rp-3.0A |
| |
| If (ROLE_CONTROL.CC2=Rd) or (ConnectResult=1) |
| 00b: SNK.Open (Below maximum vRa) |
| 01b: SNK.Default (Above minimum vRd-Connect) |
| 10b: SNK.Power1.5 (Above minimum vRd-Connect) Detects Rp 1.5A |
| 11b: SNK.Power3.0 (Above minimum vRd-Connect) Detects Rp 3.0A |
| |
| Fixes: 74e656d6b0551 ("staging: typec: Type-C Port Controller Interface driver (tcpci)") |
| Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> |
| Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> |
| Link: https://lore.kernel.org/r/20210304070931.1947316-1-badhri@google.com |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/usb/typec/tcpm/tcpci.c | 21 ++++++++++++++++++--- |
| 1 file changed, 18 insertions(+), 3 deletions(-) |
| |
| diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c |
| index f676abab044b..577cd8c6966c 100644 |
| --- a/drivers/usb/typec/tcpm/tcpci.c |
| +++ b/drivers/usb/typec/tcpm/tcpci.c |
| @@ -24,6 +24,15 @@ |
| #define AUTO_DISCHARGE_PD_HEADROOM_MV 850 |
| #define AUTO_DISCHARGE_PPS_HEADROOM_MV 1250 |
| |
| +#define tcpc_presenting_cc1_rd(reg) \ |
| + (!(TCPC_ROLE_CTRL_DRP & (reg)) && \ |
| + (((reg) & (TCPC_ROLE_CTRL_CC1_MASK << TCPC_ROLE_CTRL_CC1_SHIFT)) == \ |
| + (TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC1_SHIFT))) |
| +#define tcpc_presenting_cc2_rd(reg) \ |
| + (!(TCPC_ROLE_CTRL_DRP & (reg)) && \ |
| + (((reg) & (TCPC_ROLE_CTRL_CC2_MASK << TCPC_ROLE_CTRL_CC2_SHIFT)) == \ |
| + (TCPC_ROLE_CTRL_CC_RD << TCPC_ROLE_CTRL_CC2_SHIFT))) |
| + |
| struct tcpci { |
| struct device *dev; |
| |
| @@ -178,19 +187,25 @@ static int tcpci_get_cc(struct tcpc_dev *tcpc, |
| enum typec_cc_status *cc1, enum typec_cc_status *cc2) |
| { |
| struct tcpci *tcpci = tcpc_to_tcpci(tcpc); |
| - unsigned int reg; |
| + unsigned int reg, role_control; |
| int ret; |
| |
| + ret = regmap_read(tcpci->regmap, TCPC_ROLE_CTRL, &role_control); |
| + if (ret < 0) |
| + return ret; |
| + |
| ret = regmap_read(tcpci->regmap, TCPC_CC_STATUS, ®); |
| if (ret < 0) |
| return ret; |
| |
| *cc1 = tcpci_to_typec_cc((reg >> TCPC_CC_STATUS_CC1_SHIFT) & |
| TCPC_CC_STATUS_CC1_MASK, |
| - reg & TCPC_CC_STATUS_TERM); |
| + reg & TCPC_CC_STATUS_TERM || |
| + tcpc_presenting_cc1_rd(role_control)); |
| *cc2 = tcpci_to_typec_cc((reg >> TCPC_CC_STATUS_CC2_SHIFT) & |
| TCPC_CC_STATUS_CC2_MASK, |
| - reg & TCPC_CC_STATUS_TERM); |
| + reg & TCPC_CC_STATUS_TERM || |
| + tcpc_presenting_cc2_rd(role_control)); |
| |
| return 0; |
| } |
| -- |
| 2.30.2 |
| |