diff options
| author | Caveh Jalali <caveh@chromium.org> | 2021-06-10 01:30:39 -0700 |
|---|---|---|
| committer | Commit Bot <commit-bot@chromium.org> | 2021-06-16 05:48:46 +0000 |
| commit | adb8ca2325f4768251d3e6584ecd7b3841419571 (patch) | |
| tree | b5533968c336841fc7f08436e70c8fdb1dac17b7 | |
| parent | 65fb698e83dda45b1f5c657053ea6224a0275303 (diff) | |
| download | chrome-ec-stabilize-14031.B-main.tar.gz | |
usb_mux: Avoid accessing unavailable muxesstabilize-14031.B-main
This adds additional checks to avoid mux device accesses when the
generic mux driver knows that the device has not been initialized or is
in low power mode. This avoids spurious I2C transaction failures when
attempting to access unavailable devices.
BRANCH=none
BUG=none
TEST=observed "C0: Retimer I2C write err=1" messages are gone
Signed-off-by: Caveh Jalali <caveh@chromium.org>
Change-Id: I762a878f2cab91ca98fd7a602e0b20be8b85ccd8
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2955610
Reviewed-by: Diana Z <dzigterman@chromium.org>
| -rw-r--r-- | driver/usb_mux/usb_mux.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/driver/usb_mux/usb_mux.c b/driver/usb_mux/usb_mux.c index c50189bb40..ad347c284f 100644 --- a/driver/usb_mux/usb_mux.c +++ b/driver/usb_mux/usb_mux.c @@ -164,11 +164,23 @@ static void enter_low_power_mode(int port) configure_mux(port, USB_MUX_LOW_POWER, NULL); } -static inline void exit_low_power_mode(int port) +static int exit_low_power_mode(int port) { /* If we are in low power, initialize device (which clears LPM flag) */ if (flags[port] & USB_MUX_FLAG_IN_LPM) usb_mux_init(port); + + if (!(flags[port] & USB_MUX_FLAG_INIT)) { + CPRINTS("C%d: USB_MUX_FLAG_INIT not set", port); + return EC_ERROR_UNKNOWN; + } + + if (flags[port] & USB_MUX_FLAG_IN_LPM) { + CPRINTS("C%d: USB_MUX_FLAG_IN_LPM not cleared", port); + return EC_ERROR_NOT_POWERED; + } + + return EC_SUCCESS; } void usb_mux_init(int port) @@ -228,7 +240,8 @@ void usb_mux_set(int port, mux_state_t mux_mode, if (should_enter_low_power_mode && (flags[port] & USB_MUX_FLAG_IN_LPM)) return; - exit_low_power_mode(port); + if (exit_low_power_mode(port) != EC_SUCCESS) + return; /* Configure superspeed lanes */ mux_state = ((mux_mode != USB_PD_MUX_NONE) && polarity) @@ -313,7 +326,8 @@ void usb_mux_flip(int port) if (!(flags[port] & USB_MUX_FLAG_INIT)) usb_mux_init(port); - exit_low_power_mode(port); + if (exit_low_power_mode(port) != EC_SUCCESS) + return; if (configure_mux(port, USB_MUX_GET_MODE, &mux_state)) return; @@ -339,6 +353,9 @@ void usb_mux_hpd_update(int port, int hpd_lvl, int hpd_irq) if (!(flags[port] & USB_MUX_FLAG_INIT)) usb_mux_init(port); + if (exit_low_power_mode(port) != EC_SUCCESS) + return; + for (; mux_ptr; mux_ptr = mux_ptr->next_mux) if (mux_ptr->hpd_update) mux_ptr->hpd_update(mux_ptr, hpd_lvl, hpd_irq); |