Commit f7d0806b authored by Manivannan Sadhasivam's avatar Manivannan Sadhasivam Committed by Greg Kroah-Hartman
Browse files

bus: mhi: ep: Add support for handling SYS_ERR condition 



Add support for handling SYS_ERR (System Error) condition in the MHI
endpoint stack. The SYS_ERR flag will be asserted by the endpoint device
when it detects an internal error. The host will then issue reset and
reinitializes MHI to recover from the error state.

Reviewed-by: default avatarAlex Elder <elder@linaro.org>
Signed-off-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-13-manivannan.sadhasivam@linaro.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 7a97b6b4

drivers/bus/mhi/ep/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -211,5 +211,6 @@ int mhi_ep_set_mhi_state(struct mhi_ep_cntrl *mhi_cntrl, enum mhi_state mhi_stat 
int mhi_ep_set_m0_state(struct mhi_ep_cntrl *mhi_cntrl);

int mhi_ep_set_m3_state(struct mhi_ep_cntrl *mhi_cntrl);

int mhi_ep_set_ready_state(struct mhi_ep_cntrl *mhi_cntrl);

void mhi_ep_handle_syserr(struct mhi_ep_cntrl *mhi_cntrl);



#endif

drivers/bus/mhi/ep/main.c

+20 −0
Original line number Diff line number Diff line
@@ -516,6 +516,26 @@ static void mhi_ep_reset_worker(struct work_struct *work) 
	}

}



/*

 * We don't need to do anything special other than setting the MHI SYS_ERR

 * state. The host will reset all contexts and issue MHI RESET so that we

 * could also recover from error state.

 */

void mhi_ep_handle_syserr(struct mhi_ep_cntrl *mhi_cntrl)

{

	struct device *dev = &mhi_cntrl->mhi_dev->dev;

	int ret;



	ret = mhi_ep_set_mhi_state(mhi_cntrl, MHI_STATE_SYS_ERR);

	if (ret)

		return;



	/* Signal host that the device went to SYS_ERR state */

	ret = mhi_ep_send_state_change_event(mhi_cntrl, MHI_STATE_SYS_ERR);

	if (ret)

		dev_err(dev, "Failed sending SYS_ERR state change event: %d\n", ret);

}



int mhi_ep_power_up(struct mhi_ep_cntrl *mhi_cntrl)

{

	struct device *dev = &mhi_cntrl->mhi_dev->dev;

drivers/bus/mhi/ep/sm.c

+9 −2
Original line number Diff line number Diff line
@@ -68,8 +68,10 @@ int mhi_ep_set_m0_state(struct mhi_ep_cntrl *mhi_cntrl) 
	ret = mhi_ep_set_mhi_state(mhi_cntrl, MHI_STATE_M0);

	spin_unlock_bh(&mhi_cntrl->state_lock);



	if (ret)

	if (ret) {

		mhi_ep_handle_syserr(mhi_cntrl);

		return ret;

	}



	/* Signal host that the device moved to M0 */

	ret = mhi_ep_send_state_change_event(mhi_cntrl, MHI_STATE_M0);
@@ -99,8 +101,10 @@ int mhi_ep_set_m3_state(struct mhi_ep_cntrl *mhi_cntrl) 
	ret = mhi_ep_set_mhi_state(mhi_cntrl, MHI_STATE_M3);

	spin_unlock_bh(&mhi_cntrl->state_lock);



	if (ret)

	if (ret) {

		mhi_ep_handle_syserr(mhi_cntrl);

		return ret;

	}



	/* Signal host that the device moved to M3 */

	ret = mhi_ep_send_state_change_event(mhi_cntrl, MHI_STATE_M3);
@@ -132,5 +136,8 @@ int mhi_ep_set_ready_state(struct mhi_ep_cntrl *mhi_cntrl) 
	ret = mhi_ep_set_mhi_state(mhi_cntrl, MHI_STATE_READY);

	spin_unlock_bh(&mhi_cntrl->state_lock);



	if (ret)

		mhi_ep_handle_syserr(mhi_cntrl);



	return ret;

}