[v7,5/7] bus: mhi: core: Check channel execution environment before issuing reset
diff mbox series

Message ID 1617070307-5775-6-git-send-email-bbhatt@codeaurora.org
State New, archived
Headers show
Series
  • [v7,1/7] bus: mhi: core: Allow sending the STOP channel command
Related show

Commit Message

Bhaumik Bhatt March 30, 2021, 2:11 a.m. UTC
A client can attempt to unprepare certain channels for transfer even
after the execution environment they are supposed to run in has changed.
In the event that happens, the device need not be notified of the reset
and the host can proceed with clean up for the channel context and
memory allocated for it on the host as the device will no longer be able
to respond to such a request.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/bus/mhi/core/main.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

Patch
diff mbox series

diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c
index 6c3234e..f34f8f6 100644
--- a/drivers/bus/mhi/core/main.c
+++ b/drivers/bus/mhi/core/main.c
@@ -1303,6 +1303,12 @@  static void __mhi_unprepare_channel(struct mhi_controller *mhi_cntrl,
 
 	mutex_lock(&mhi_chan->mutex);
 
+	if (!(BIT(mhi_cntrl->ee) & mhi_chan->ee_mask)) {
+		dev_dbg(dev, "Current EE: %s Required EE Mask: 0x%x\n",
+			TO_MHI_EXEC_STR(mhi_cntrl->ee), mhi_chan->ee_mask);
+		goto exit_unprepare_channel;
+	}
+
 	/* no more processing events for this channel */
 	ret = mhi_update_channel_state(mhi_cntrl, mhi_chan,
 				       MHI_CH_STATE_TYPE_RESET);
@@ -1310,6 +1316,11 @@  static void __mhi_unprepare_channel(struct mhi_controller *mhi_cntrl,
 		dev_err(dev, "%d: Failed to reset channel, still resetting\n",
 			mhi_chan->chan);
 
+exit_unprepare_channel:
+	write_lock_irq(&mhi_chan->lock);
+	mhi_chan->ch_state = MHI_CH_STATE_DISABLED;
+	write_unlock_irq(&mhi_chan->lock);
+
 	if (!mhi_chan->offload_ch) {
 		mhi_reset_chan(mhi_cntrl, mhi_chan);
 		mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan);