[PATCH 14/14] bus: mhi: core: Handle syserr during power_up

mani
2020-05-21T15:26:58Z

From: Jeffrey Hugo <jhugo@codeaurora.org>

The MHI device may be in the syserr state when we attempt to init it in
power_up(). Since we have no local state, the handling is simple -
reset the device and wait for it to transition out of the reset state.

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
drivers/bus/mhi/core/pm.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)

diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index e6236a3ca39d..1bd61a64d7bb 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -763,6 +763,7 @@ static void mhi_deassert_dev_wake(struct mhi_controller *mhi_cntrl,

int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
{
+ enum mhi_state state;
enum mhi_ee_type current_ee;
enum dev_st_transition next_state;
struct device *dev = &mhi_cntrl->mhi_dev->dev;
@@ -832,6 +833,32 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
goto error_bhi_offset;
}

+ state = mhi_get_mhi_state(mhi_cntrl);
+ if (state == MHI_STATE_SYS_ERR) {
+ mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);
+ ret = wait_event_timeout(mhi_cntrl->state_event,
+ MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state) ||
+ mhi_read_reg_field(mhi_cntrl,
+ mhi_cntrl->regs,
+ MHICTRL,
+ MHICTRL_RESET_MASK,
+ MHICTRL_RESET_SHIFT,
+ &val) ||
+ !val,
+ msecs_to_jiffies(mhi_cntrl->timeout_ms));
+ if (ret) {
+ ret = -EIO;
+ dev_info(dev, "Failed to reset MHI due to syserr state\n");
+ goto error_bhi_offset;
+ }
+
+ /*
+ * device cleares INTVEC as part of RESET processing,
+ * re-program it
+ */
+ mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
+ }
+
/* Transition to next state */
next_state = MHI_IN_PBL(current_ee) ?
DEV_ST_TRANSITION_PBL : DEV_ST_TRANSITION_READY;
--
2.26.GIT