Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0ca85fbd authored by Lena Salman's avatar Lena Salman
Browse files

usb_bam: Solve the deadlock on WWAN wakeup during suspend 



On MAC-ECM suspend a crash is occurring when embedded
call is waking up the whole system.
This happens due to deadlock of resource manager dependecies.
This solution tries to address it from the USB point of view, removing the
dependency  between the CONS and PROD on remote wakeup.

Change-Id: I7ef4fa504627bd78c36794ff8327f3851229d7ed
Signed-off-by: default avatarLena Salman <esalman@codeaurora.org>
parent d80a3f91

drivers/platform/msm/usb_bam.c

+36 −3
Original line number Diff line number Diff line
@@ -1396,6 +1396,8 @@ static void usb_bam_finish_resume(struct work_struct *w) 
{

	struct usb_phy *phy = usb_get_phy(USB_PHY_TYPE_USB2);

	enum usb_bam cur_bam = HSUSB_BAM;

	struct usb_bam_pipe_connect *pipe_connect;

	u32 idx, dst_idx, suspended;



	BUG_ON(IS_ERR_OR_NULL(phy));

	pr_debug("%s: enter", __func__);
@@ -1411,6 +1413,29 @@ static void usb_bam_finish_resume(struct work_struct *w) 
	}

	info[cur_bam].pipes_to_suspend = 0;

	info[cur_bam].lpm_wait_handshake = true;



	pr_debug("Resuming: pipes_suspended =%d",

		 info[cur_bam].pipes_suspended);



	suspended = info[cur_bam].pipes_suspended;

	while (suspended >= 1) {

		idx = suspended - 1;

		dst_idx = info[cur_bam].resume_dst_idx[idx];

		pipe_connect = &usb_bam_connections[dst_idx];

		if (pipe_connect->cons_stopped) {

			spin_unlock(&usb_bam_ipa_handshake_info_lock);

			ipa_resume_pipes(idx);

			spin_lock(&usb_bam_ipa_handshake_info_lock);

			pr_debug("%s: Starting CONS on %d", __func__, dst_idx);

			start_cons_transfers(pipe_connect);

		}

		suspended--;

	}

	if (info[cur_bam].cur_cons_state == IPA_RM_RESOURCE_GRANTED) {

		pr_debug("%s: Notify CONS_GRANTED\n", __func__);

		ipa_rm_notify_completion(IPA_RM_RESOURCE_GRANTED,

				 ipa_rm_resource_cons[HSUSB_BAM]);

	}

	spin_unlock(&usb_bam_ipa_handshake_info_lock);



	/* Start handshake for the first pipe resumed */
@@ -1418,8 +1443,15 @@ static void usb_bam_finish_resume(struct work_struct *w) 
		wait_for_prod_granted(cur_bam);



	spin_lock(&usb_bam_ipa_handshake_info_lock);



	resume_suspended_pipes(cur_bam);

	while (info[cur_bam].pipes_suspended >= 1) {

		idx = info[cur_bam].pipes_suspended - 1;

		dst_idx = info[cur_bam].resume_dst_idx[idx];

		pipe_connect = &usb_bam_connections[dst_idx];

		pr_debug("%s: Starting PROD on %d", __func__, dst_idx);

		start_prod_transfers(pipe_connect);

		info[cur_bam].pipes_suspended--;

		info[cur_bam].pipes_resumed++;

	}



	if (info[cur_bam].pipes_resumed * 2 ==

	      ctx.pipes_enabled_per_bam[cur_bam]) {
@@ -1430,6 +1462,7 @@ static void usb_bam_finish_resume(struct work_struct *w) 
						 ipa_rm_resource_cons[cur_bam]);

		}

	}



	spin_unlock(&usb_bam_ipa_handshake_info_lock);

	mutex_unlock(&info[cur_bam].suspend_resume_mutex);

	pr_debug("%s: done", __func__);