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 <bbhatt@xxxxxxxxxxxxxx>
---
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,
--
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