[PATCH 18/75] staging: vt6656: [bug] Fix missing spin lock in iwctl_siwpower.

[Kamal Mostafa]

3.8.13.2 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Malcolm Priestley <tvboxspy@xxxxxxxxx>

commit 91ec61f8f01cf32868e2ed2fa96a299e77964055 upstream.

Fixes occasional dead lock on power up / down.

spin_lock_irq is used because of unlocking with spin_unlock_irq
elsewhere in the driver.

Only relevant to kernels 3.8 and later when command was
transferred to the iw_handler.

Signed-off-by: Malcolm Priestley <tvboxspy@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
 drivers/staging/vt6656/iwctl.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/staging/vt6656/iwctl.c b/drivers/staging/vt6656/iwctl.c
index 52fce69..9f2f1be 100644
--- a/drivers/staging/vt6656/iwctl.c
+++ b/drivers/staging/vt6656/iwctl.c
@@ -1348,9 +1348,12 @@ int iwctl_siwpower(struct net_device *dev, struct iw_request_info *info,
 		return rc;
 	}
 
+	spin_lock_irq(&pDevice->lock);
+
 	if (wrq->disabled) {
 		pDevice->ePSMode = WMAC_POWER_CAM;
 		PSvDisablePowerSaving(pDevice);
+		spin_unlock_irq(&pDevice->lock);
 		return rc;
 	}
 	if ((wrq->flags & IW_POWER_TYPE) == IW_POWER_TIMEOUT) {
@@ -1361,6 +1364,9 @@ int iwctl_siwpower(struct net_device *dev, struct iw_request_info *info,
 		pDevice->ePSMode = WMAC_POWER_FAST;
 		PSvEnablePowerSaving((void *)pDevice, pMgmt->wListenInterval);
 	}
+
+	spin_unlock_irq(&pDevice->lock);
+
 	switch (wrq->flags & IW_POWER_MODE) {
 	case IW_POWER_UNICAST_R:
 		DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO " SIOCSIWPOWER: IW_POWER_UNICAST_R \n");
-- 
1.8.1.2

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