From: Krzysztof Hałasa <khalasa@piap.pl>
Date: Mon, 8 Jun 2015 13:42:24 +0000 (-0300)
Subject: [media] SOLO6x10: remove unneeded register locking and barriers
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=e1ceb25a1569ce5b61b9c496dd32d038ba8cb936;p=deliverable%2Flinux.git

[media] SOLO6x10: remove unneeded register locking and barriers

readl() and writel() are atomic, we don't need the spin lock.
Also, flushing posted write buffer isn't required. Especially on read :-)

Signed-off-by: Krzysztof Ha?asa <khalasa@piap.pl>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
---

diff --git a/drivers/media/pci/solo6x10/solo6x10-core.c b/drivers/media/pci/solo6x10/solo6x10-core.c
index 84627e6f7377..9c948b1fc1d8 100644
--- a/drivers/media/pci/solo6x10/solo6x10-core.c
+++ b/drivers/media/pci/solo6x10/solo6x10-core.c
@@ -483,7 +483,6 @@ static int solo_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	solo_dev->type = id->driver_data;
 	solo_dev->pdev = pdev;
-	spin_lock_init(&solo_dev->reg_io_lock);
 	ret = v4l2_device_register(&pdev->dev, &solo_dev->v4l2_dev);
 	if (ret)
 		goto fail_probe;
diff --git a/drivers/media/pci/solo6x10/solo6x10.h b/drivers/media/pci/solo6x10/solo6x10.h
index 1ca54b08b3aa..27423d7f5410 100644
--- a/drivers/media/pci/solo6x10/solo6x10.h
+++ b/drivers/media/pci/solo6x10/solo6x10.h
@@ -199,7 +199,6 @@ struct solo_dev {
 	int			nr_ext;
 	u32			irq_mask;
 	u32			motion_mask;
-	spinlock_t		reg_io_lock;
 	struct v4l2_device	v4l2_dev;
 
 	/* tw28xx accounting */
@@ -281,36 +280,13 @@ struct solo_dev {
 
 static inline u32 solo_reg_read(struct solo_dev *solo_dev, int reg)
 {
-	unsigned long flags;
-	u32 ret;
-	u16 val;
-
-	spin_lock_irqsave(&solo_dev->reg_io_lock, flags);
-
-	ret = readl(solo_dev->reg_base + reg);
-	rmb();
-	pci_read_config_word(solo_dev->pdev, PCI_STATUS, &val);
-	rmb();
-
-	spin_unlock_irqrestore(&solo_dev->reg_io_lock, flags);
-
-	return ret;
+	return readl(solo_dev->reg_base + reg);
 }
 
 static inline void solo_reg_write(struct solo_dev *solo_dev, int reg,
 				  u32 data)
 {
-	unsigned long flags;
-	u16 val;
-
-	spin_lock_irqsave(&solo_dev->reg_io_lock, flags);
-
 	writel(data, solo_dev->reg_base + reg);
-	wmb();
-	pci_read_config_word(solo_dev->pdev, PCI_STATUS, &val);
-	rmb();
-
-	spin_unlock_irqrestore(&solo_dev->reg_io_lock, flags);
 }
 
 static inline void solo_irq_on(struct solo_dev *dev, u32 mask)