u8500: shrm: Update AC_Wake logic and one fix for MSR

Updates the AC_Wake logic related to MSR.
Also, corrects one NULL pointer dereference.

ST-Ericsson ID: ER335373

Change-Id: Ie3f46c2a7bcdde9936a0f9eed52f8dcd0ab5a06b
Signed-off-by: Kumar Sanghvi <kumar.sanghvi@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/21162
Reviewed-by: QATEST
Reviewed-by: Srinidhi KASAGAR <srinidhi.kasagar@stericsson.com>

2 files changed, 14 insertions, 22 deletions

diff --git a/drivers/char/shrm_char.c b/drivers/char/shrm_char.c
index e2aaf60674f..6a6b3d7245a 100644
--- a/drivers/char/shrm_char.c
+++ b/drivers/char/shrm_char.c
@@ -236,25 +236,26 @@ int remove_msg_from_queue(struct message_queue *q)
 {
 	struct queue_element *old_msg = NULL;
 	struct shrm_dev *shrm = q->shrm;
-	struct list_head *msg;
+	struct list_head *msg_ptr = NULL;
+	struct list_head *old_msg_ptr = NULL;
 
 	dev_dbg(shrm->dev, "%s IN q->readptr %d\n", __func__, q->readptr);
 
-	list_for_each(msg, &q->msg_list) {
-		old_msg = list_entry(msg, struct queue_element, entry);
+	list_for_each_safe(old_msg_ptr, msg_ptr, &q->msg_list) {
+		old_msg = list_entry(old_msg_ptr, struct queue_element, entry);
 		if (old_msg == NULL) {
 			dev_err(shrm->dev, "no message found\n");
 			return -EFAULT;
 		}
+		list_del(old_msg_ptr);
+		q->readptr = (q->readptr + old_msg->size)%q->size;
+		kfree(old_msg);
 		break;
 	}
-	list_del(msg);
-	q->readptr = (q->readptr + old_msg->size)%q->size;
 	if (list_empty(&q->msg_list)) {
 		dev_dbg(shrm->dev, "List is empty setting RP= 0\n");
 		atomic_set(&q->q_rp, 0);
 	}
-	kfree(old_msg);
 
 	dev_dbg(shrm->dev, "%s OUT\n", __func__);
 	return 0;
diff --git a/drivers/misc/shrm/shrm_protocol.c b/drivers/misc/shrm/shrm_protocol.c
index 0831bc8803e..0598c62812f 100644
--- a/drivers/misc/shrm/shrm_protocol.c
+++ b/drivers/misc/shrm/shrm_protocol.c
@@ -80,14 +80,6 @@ static void shm_ac_sleep_req_work(struct work_struct *work)
 static void shm_ac_wake_req_work(struct work_struct *work)
 {
 	mutex_lock(&ac_state_mutex);
-	/* make sure that we bring down the ac-wake line
-	 * so that prcmu driver will actually write
-	 * to the PRCM_HOSTACCESS_REQ register on the
-	 * next prcmu_ac_wake_req call
-	 */
-	prcmu_ac_sleep_req();
-
-	atomic_inc(&ac_sleep_disable_count);
 	prcmu_ac_wake_req();
 	mutex_unlock(&ac_state_mutex);
 }
@@ -384,13 +376,6 @@ void shm_ac_read_notif_0_tasklet(unsigned long tasklet_data)
 
 			/* multicast that modem is online */
 			nl_send_multicast_message(SHRM_NL_STATUS_MOD_ONLINE, GFP_ATOMIC);
-
-			/* This decrement corresponds to increment
-			 * done in MSR sequecne
-			 */
-			atomic_dec(&ac_sleep_disable_count);
-			queue_work(shm_dev->shm_ac_sleep_wq,
-					&shm_dev->shm_ac_sleep_req);
 		}
 
 	} else if (boot_state == BOOT_DONE) {
@@ -523,9 +508,13 @@ static int shrm_modem_reset_sequence(void)
 
 	hrtimer_cancel(&timer);
 
-	/* reset the state for ac-wake LOW logic */
+	/*
+	 * keep the count to 0 so that we can bring down the line
+	 * for normal ac-wake and ac-sleep logic
+	 */
 	atomic_set(&ac_sleep_disable_count, 0);
 
+	/* workaround for MSR */
 	queue_work(shm_dev->shm_ac_wake_wq,
 			&shm_dev->shm_ac_wake_req);
 
@@ -598,6 +587,8 @@ static irqreturn_t shrm_prcmu_irq_handler(int irq, void *data)
 #ifdef CONFIG_UX500_SUSPEND
 		suspend_block_sleep();
 #endif
+		if (shrm->msr_flag)
+			atomic_set(&ac_sleep_disable_count, 0);
 		atomic_inc(&ac_sleep_disable_count);
 		queue_work(shrm->shm_ca_wake_wq, &shrm->shm_ca_wake_req);
 		break;