From fbb46ea6d6e8adc9162ae37ecda555436a6a206d Mon Sep 17 00:00:00 2001
From: kfx <kfx@rock-chips.com>
Date: Mon, 20 Jun 2011 10:06:28 +0800
Subject: [PATCH] update adc driver: interrupt add spin_lock

---
 drivers/adc/core.c          | 21 ++++++++++++++-------
 drivers/adc/plat/rk29_adc.c |  2 +-
 include/linux/adc.h         |  2 +-
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/drivers/adc/core.c b/drivers/adc/core.c
index dea19cc744d9..0756c7ea4f80 100755
--- a/drivers/adc/core.c
+++ b/drivers/adc/core.c
@@ -91,14 +91,14 @@ static int
 adc_enqueue_request(struct adc_host *adc, struct adc_request *req)
 {
 	int head, tail;
-
-	mutex_lock(&adc->queue_mutex);
-
+	unsigned long flags;
+	
+	spin_lock_irqsave(&adc->lock, flags);
 	head = adc->queue_head;
 	tail = adc->queue_tail;
 
 	if (adc->queue[tail]) {
-		mutex_unlock(&adc->queue_mutex);
+		spin_unlock_irqrestore(&adc->lock,flags);
 		dev_err(adc->dev, "ADC queue is full, dropping request\n");
 		return -EBUSY;
 	}
@@ -108,7 +108,7 @@ adc_enqueue_request(struct adc_host *adc, struct adc_request *req)
 		trigger_next_adc_job_if_any(adc);
 	adc->queue_tail = (tail + 1) & (MAX_ADC_FIFO_DEPTH - 1);
 
-	mutex_unlock(&adc->queue_mutex);
+	spin_unlock_irqrestore(&adc->lock,flags);
 
 	return 0;
 }
@@ -169,6 +169,7 @@ EXPORT_SYMBOL(adc_sync_read);
 
 int adc_async_read(struct adc_client *client)
 {
+	int ret = 0;
 	struct adc_request *req = NULL;
 	
 	if(client == NULL) {
@@ -190,7 +191,11 @@ int adc_async_read(struct adc_client *client)
 	req->client = client;
 	req->status = ASYNC_READ;
 
-	return adc_enqueue_request(client->adc, req);
+	ret = adc_enqueue_request(client->adc, req);
+	if(ret < 0)
+		kfree(req);
+
+	return ret;
 }
 EXPORT_SYMBOL(adc_async_read);
 
@@ -198,11 +203,12 @@ void adc_core_irq_handle(struct adc_host *adc)
 {
 	struct adc_request *req;
 	int head, res;
-
+	spin_lock(adc->lock);
 	head = adc->queue_head;
 
 	req = adc->queue[head];
 	if (WARN_ON(!req)) {
+		spin_unlock(&adc->lock);
 		dev_err(adc->dev, "adc irq: ADC queue empty!\n");
 		return;
 	}
@@ -218,6 +224,7 @@ void adc_core_irq_handle(struct adc_host *adc)
 		kfree(req);
 		req = NULL;
 	}
+	spin_unlock(&adc->lock);
 }
 EXPORT_SYMBOL(adc_core_irq_handle);
 
diff --git a/drivers/adc/plat/rk29_adc.c b/drivers/adc/plat/rk29_adc.c
index 6bf01ba8c56f..2471abafff0b 100755
--- a/drivers/adc/plat/rk29_adc.c
+++ b/drivers/adc/plat/rk29_adc.c
@@ -123,7 +123,7 @@ static int rk29_adc_probe(struct platform_device *pdev)
 	adc = adc_alloc_host(sizeof(struct rk29_adc_device), &pdev->dev);
 	if (!adc)
 		return -ENOMEM;
-	mutex_init(&adc->queue_mutex);
+	spin_lock_init(&adc->lock);
 	adc->dev = &pdev->dev;
 	adc->is_suspended = 0;
 	adc->ops = &rk29_adc_ops;
diff --git a/include/linux/adc.h b/include/linux/adc.h
index d9ed72afbe0f..22c781fbd305 100755
--- a/include/linux/adc.h
+++ b/include/linux/adc.h
@@ -49,7 +49,7 @@ struct adc_host {
 	struct adc_request *queue[MAX_ADC_FIFO_DEPTH];
 	int queue_head;
 	int queue_tail;
-	struct mutex queue_mutex;
+	spinlock_t			lock;
 	struct adc_client *cur;
 	const struct adc_ops *ops;
 	unsigned long		private[0];
-- 
2.34.1