linux-kernel - [char-misc 3.11 V2] mei: me: fix hardware reset flow

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Date:	Tue, 30 Jul 2013 14:11:51 +0300
From:	Tomas Winkler <tomas.winkler@...el.com>
To:	gregkh@...uxfoundation.org
Cc:	arnd@...db.de, linux-kernel@...r.kernel.org,
	Tomas Winkler <tomas.winkler@...el.com>,
	Shuah Khan <shuah.kh@...sung.com>,
	Konstantin Khlebnikov <khlebnikov@...nvz.org>
Subject: [char-misc 3.11 V2] mei: me: fix hardware reset flow

Both H_IS and H_IE needs to be set to receive H_RDY 
interrupt

1. Assert H_IS to clear the interrupts during hw reset
and use mei_me_reg_write instead of mei_hcsr_set as the later
strips down the H_IS

2. fix interrupt disablement embarrassing typo
  hcsr |= ~H_IE -> hcsr &= ~H_IE;
this will remove the unwanted interrupt on power down

3. remove useless debug print outs

Cc: Shuah Khan <shuah.kh@...sung.com>
Cc: Konstantin Khlebnikov <khlebnikov@...nvz.org>
Signed-off-by: Tomas Winkler <tomas.winkler@...el.com>
---

V2: Fixed typo in Shuah email

Hope this finally resolve the ME reset issue for all

 drivers/misc/mei/hw-me.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index b22c7e2..3412adc 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -176,21 +176,18 @@ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable)
 	struct mei_me_hw *hw = to_me_hw(dev);
 	u32 hcsr = mei_hcsr_read(hw);
 
-	dev_dbg(&dev->pdev->dev, "before reset HCSR = 0x%08x.\n", hcsr);
-
-	hcsr |= (H_RST | H_IG);
+	hcsr |= H_RST | H_IG | H_IS;
 
 	if (intr_enable)
 		hcsr |= H_IE;
 	else
-		hcsr |= ~H_IE;
+		hcsr &= ~H_IE;
 
-	mei_hcsr_set(hw, hcsr);
+	mei_me_reg_write(hw, H_CSR, hcsr);
 
 	if (dev->dev_state == MEI_DEV_POWER_DOWN)
 		mei_me_hw_reset_release(dev);
 
-	dev_dbg(&dev->pdev->dev, "current HCSR = 0x%08x.\n", mei_hcsr_read(hw));
 	return 0;
 }
 
-- 
1.8.1.2

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