linux-kernel - [char-misc-next 16/21] mei: don't use cached value for hcsr in mei_hw

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Date:	Tue,  8 Jan 2013 23:07:27 +0200
From:	Tomas Winkler <tomas.winkler@...el.com>
To:	gregkh@...uxfoundation.org
Cc:	arnd@...db.de, alan@...ux.intel.com, linux-kernel@...r.kernel.org,
	Tomas Winkler <tomas.winkler@...el.com>
Subject: [char-misc-next 16/21] mei: don't use cached value for hcsr in mei_hw_reset

Open code mei_hw_reset to avoid using cached hcsr.
Using cached hcsr can cause unwanted side effects.

Move mei_hw_restet function to hw-me.c as it is hw dependent

Signed-off-by: Tomas Winkler <tomas.winkler@...el.com>
---
 drivers/misc/mei/hw-me.c   |   35 +++++++++++++++++++++++++++++++++++
 drivers/misc/mei/init.c    |   28 ----------------------------
 drivers/misc/mei/mei_dev.h |    1 +
 3 files changed, 36 insertions(+), 28 deletions(-)

diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index 1e82e33..ec4ab89 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -132,6 +132,41 @@ void mei_disable_interrupts(struct mei_device *dev)
 	mei_hcsr_set(dev);
 }
 
+/**
+ * mei_hw_reset - resets fw via mei csr register.
+ *
+ * @dev: the device structure
+ * @interrupts_enabled: if interrupt should be enabled after reset.
+ */
+void mei_hw_reset(struct mei_device *dev, bool intr_enable)
+{
+	u32 hcsr = mei_hcsr_read(dev);
+
+	dev_dbg(&dev->pdev->dev, "before reset HCSR = 0x%08x.\n", hcsr);
+
+	hcsr |= (H_RST | H_IG);
+
+	if (intr_enable)
+		hcsr |= H_IE;
+	else
+		hcsr &= ~H_IE;
+
+	hcsr &= ~H_IS;
+
+	mei_reg_write(dev, H_CSR, hcsr);
+	hcsr = mei_hcsr_read(dev);
+
+	hcsr &= ~H_RST;
+	hcsr |= H_IG;
+	hcsr &= ~H_IS;
+
+	mei_reg_write(dev, H_CSR, hcsr);
+
+	hcsr = mei_hcsr_read(dev);
+
+	dev_dbg(&dev->pdev->dev, "current HCSR = 0x%08x.\n", hcsr);
+}
+
 
 /**
  * mei_interrupt_quick_handler - The ISR of the MEI device
diff --git a/drivers/misc/mei/init.c b/drivers/misc/mei/init.c
index 2391832..5c2054d 100644
--- a/drivers/misc/mei/init.c
+++ b/drivers/misc/mei/init.c
@@ -170,22 +170,6 @@ out:
 }
 
 /**
- * mei_hw_reset - resets fw via mei csr register.
- *
- * @dev: the device structure
- * @interrupts_enabled: if interrupt should be enabled after reset.
- */
-static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
-{
-	dev->host_hw_state |= (H_RST | H_IG);
-
-	if (interrupts_enabled)
-		mei_enable_interrupts(dev);
-	else
-		mei_disable_interrupts(dev);
-}
-
-/**
  * mei_reset - resets host and fw.
  *
  * @dev: the device structure
@@ -207,20 +191,8 @@ void mei_reset(struct mei_device *dev, int interrupts_enabled)
 			dev->dev_state != MEI_DEV_POWER_DOWN &&
 			dev->dev_state != MEI_DEV_POWER_UP);
 
-	dev->host_hw_state = mei_hcsr_read(dev);
-
-	dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
-	    dev->host_hw_state);
-
 	mei_hw_reset(dev, interrupts_enabled);
 
-	dev->host_hw_state &= ~H_RST;
-	dev->host_hw_state |= H_IG;
-
-	mei_hcsr_set(dev);
-
-	dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
-	    dev->host_hw_state);
 
 	if (dev->dev_state != MEI_DEV_INITIALIZING) {
 		if (dev->dev_state != MEI_DEV_DISABLED &&
diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index 88fa194..8692ac8 100644
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -385,6 +385,7 @@ void mei_watchdog_unregister(struct mei_device *dev);
  * Register Access Function
  */
 
+void mei_hw_reset(struct mei_device *dev, bool intr_enable);
 u32 mei_hcsr_read(const struct mei_device *dev);
 void mei_hcsr_set(struct mei_device *dev);
 u32 mei_mecsr_read(const struct mei_device *dev);
-- 
1.7.4.4

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