MHI host can fail early if device is in a bad state by attempting to assert device wake and holding the runtime PM vote before sending a channel update command instead of performing a wake toggle and waiting for a timeout if the send were to fail. This can help improve the design and enable shorter wait periods for device to respond as votes are already held.
Signed-off-by: Bhaumik Bhatt <[email protected]> --- drivers/bus/mhi/core/main.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c index 94fdbf7..989a2a8 100644 --- a/drivers/bus/mhi/core/main.c +++ b/drivers/bus/mhi/core/main.c @@ -1278,16 +1278,18 @@ static int mhi_update_channel_state(struct mhi_controller *mhi_cntrl, return -EINVAL; } - mhi_cntrl->wake_toggle(mhi_cntrl); + /* bring host and device out of suspended states */ + ret = mhi_device_get_sync(mhi_cntrl->mhi_dev); + if (ret) + return ret; mhi_cntrl->runtime_get(mhi_cntrl); - mhi_cntrl->runtime_put(mhi_cntrl); reinit_completion(&mhi_chan->completion); ret = mhi_send_cmd(mhi_cntrl, mhi_chan, cmd); if (ret) { dev_err(dev, "%d: Failed to send %s channel command\n", mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); - return ret; + goto exit_channel_update; } ret = wait_for_completion_timeout(&mhi_chan->completion, @@ -1296,9 +1298,12 @@ static int mhi_update_channel_state(struct mhi_controller *mhi_cntrl, dev_err(dev, "%d: Failed to receive %s channel command completion\n", mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); - return -EIO; + ret = -EIO; + goto exit_channel_update; } + ret = 0; + if (to_state != MHI_CH_STATE_TYPE_RESET) { write_lock_irq(&mhi_chan->lock); mhi_chan->ch_state = (to_state == MHI_CH_STATE_TYPE_START) ? @@ -1309,7 +1314,11 @@ static int mhi_update_channel_state(struct mhi_controller *mhi_cntrl, dev_dbg(dev, "%d: Channel state change to %s successful\n", mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); - return 0; +exit_channel_update: + mhi_cntrl->runtime_put(mhi_cntrl); + mhi_device_put(mhi_cntrl->mhi_dev); + + return ret; } static void __mhi_unprepare_channel(struct mhi_controller *mhi_cntrl, -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
