asoc: codecs: Add mutex lock for CPE session

Add mutex lock to ensure atomic access to core handle
in CPE alloc and dealloc sessions.

CRs-Fixed: 2169403
Change-Id: I7e046f349cc56ee06706cf15651dac3fdfe9d9a6
Signed-off-by: Vaishnavi Kommaraju <vkommara@codeaurora.org>

asoc/codecs/wcd_cpe_core.c

@@ -1,4 +1,4 @@
-/* Copyright (c) 2014-2017, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2014-2018, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -1936,6 +1936,7 @@ struct wcd_cpe_core *wcd_cpe_init(const char *img_fname,
 	init_completion(&core->online_compl);
 	init_waitqueue_head(&core->ssr_entry.offline_poll_wait);
 	mutex_init(&core->ssr_lock);
+	mutex_init(&core->session_lock);
 	core->cpe_users = 0;
 	core->cpe_clk_ref = 0;
 
@@ -3387,6 +3388,7 @@ static struct cpe_lsm_session *wcd_cpe_alloc_lsm_session(
 	 * If this is the first session to be allocated,
 	 * only then register the afe service.
 	 */
+	WCD_CPE_GRAB_LOCK(&core->session_lock, "session_lock");
 	if (!wcd_cpe_lsm_session_active())
 		afe_register_service = true;
 
@@ -3401,6 +3403,7 @@ static struct cpe_lsm_session *wcd_cpe_alloc_lsm_session(
 		dev_err(core->dev,
 			"%s: max allowed sessions already allocated\n",
 			__func__);
+		WCD_CPE_REL_LOCK(&core->session_lock, "session_lock");
 		return NULL;
 	}
 
@@ -3409,6 +3412,7 @@ static struct cpe_lsm_session *wcd_cpe_alloc_lsm_session(
 		dev_err(core->dev,
 			"%s: Failed to enable cpe, err = %d\n",
 			__func__, ret);
+		WCD_CPE_REL_LOCK(&core->session_lock, "session_lock");
 		return NULL;
 	}
 
@@ -3451,6 +3455,8 @@ static struct cpe_lsm_session *wcd_cpe_alloc_lsm_session(
 	init_completion(&session->cmd_comp);
 
 	lsm_sessions[session_id] = session;
+
+	WCD_CPE_REL_LOCK(&core->session_lock, "session_lock");
 	return session;
 
 err_afe_mode_cmd:
@@ -3465,6 +3471,7 @@ static struct cpe_lsm_session *wcd_cpe_alloc_lsm_session(
 
 err_session_alloc:
 	wcd_cpe_vote(core, false);
+	WCD_CPE_REL_LOCK(&core->session_lock, "session_lock");
 	return NULL;
 }
 
@@ -3615,9 +3622,11 @@ static int wcd_cpe_dealloc_lsm_session(void *core_handle,
 	struct wcd_cpe_core *core = core_handle;
 	int ret = 0;
 
+	WCD_CPE_GRAB_LOCK(&core->session_lock, "session_lock");
 	if (!session) {
 		dev_err(core->dev,
 			"%s: Invalid lsm session\n", __func__);
+		WCD_CPE_REL_LOCK(&core->session_lock, "session_lock");
 		return -EINVAL;
 	}
 
@@ -3628,6 +3637,7 @@ static int wcd_cpe_dealloc_lsm_session(void *core_handle,
 			"%s: Wrong session id %d max allowed = %d\n",
 			__func__, session->id,
 			WCD_CPE_LSM_MAX_SESSIONS);
+		WCD_CPE_REL_LOCK(&core->session_lock, "session_lock");
 		return -EINVAL;
 	}
 
@@ -3648,6 +3658,7 @@ static int wcd_cpe_dealloc_lsm_session(void *core_handle,
 			"%s: Failed to un-vote cpe, err = %d\n",
 			__func__, ret);
 
+	WCD_CPE_REL_LOCK(&core->session_lock, "session_lock");
 	return ret;
 }
 

asoc/codecs/wcd_cpe_core.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2013-2017, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2013-2018, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -172,6 +172,9 @@ struct wcd_cpe_core {
 	/* mutex to protect cpe ssr status variables */
 	struct mutex ssr_lock;
 
+	/* mutex to protect cpe session status variables */
+	struct mutex session_lock;
+
 	/* Store the calibration data needed for cpe */
 	struct cal_type_data *cal_data[WCD_CPE_LSM_CAL_MAX];
 

asoc/codecs/wcd_cpe_services.c

@@ -1,4 +1,4 @@
-/* Copyright (c) 2014-2017, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2014-2018, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -606,8 +606,10 @@ static enum cpe_svc_result cpe_deregister_generic(struct cpe_info *t_info,
 		return CPE_SVC_INVALID_HANDLE;
 	}
 
+	CPE_SVC_GRAB_LOCK(&cpe_d.cpe_svc_lock, "cpe_svc");
 	list_del(&(n->list));
 	kfree(reg_handle);
+	CPE_SVC_REL_LOCK(&cpe_d.cpe_svc_lock, "cpe_svc");
 
 	return CPE_SVC_SUCCESS;
 }