linux-kernel - [PATCH 4/4] phy: twl4030-usb: Fix unbalanced pm_runtime

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Date:	Wed, 10 Feb 2016 12:15:08 +0530
From:	Kishon Vijay Abraham I <kishon@...com>
To:	<gregkh@...uxfoundation.org>
CC:	<linux-kernel@...r.kernel.org>
Subject: [PATCH 4/4] phy: twl4030-usb: Fix unbalanced pm_runtime_enable on module reload

From: Tony Lindgren <tony@...mide.com>

If we reload phy-twl4030-usb, we get a warning about unbalanced
pm_runtime_enable. Let's fix the issue and also fix idling of the
device on unload before we attempt to shut it down.

If we don't properly idle the PHY before shutting it down on removal,
the twl4030 ends up consuming about 62mW of extra power compared to
running idle with the module loaded.

Cc: stable@...r.kernel.org
Cc: Bin Liu <b-liu@...com>
Cc: Felipe Balbi <balbi@...com>
Cc: Kishon Vijay Abraham I <kishon@...com>
Cc: NeilBrown <neil@...wn.name>
Signed-off-by: Tony Lindgren <tony@...mide.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@...com>
---
 drivers/phy/phy-twl4030-usb.c |   13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/phy/phy-twl4030-usb.c b/drivers/phy/phy-twl4030-usb.c
index fe5538f..840f3ea 100644
--- a/drivers/phy/phy-twl4030-usb.c
+++ b/drivers/phy/phy-twl4030-usb.c
@@ -715,6 +715,7 @@ static int twl4030_usb_probe(struct platform_device *pdev)
 	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_set_autosuspend_delay(&pdev->dev, 2000);
 	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
 
 	/* Our job is to use irqs and status from the power module
 	 * to keep the transceiver disabled when nothing's connected.
@@ -758,6 +759,13 @@ static int twl4030_usb_remove(struct platform_device *pdev)
 	/* set transceiver mode to power on defaults */
 	twl4030_usb_set_mode(twl, -1);
 
+	/* idle ulpi before powering off */
+	if (cable_present(twl->linkstat))
+		pm_runtime_put_noidle(twl->dev);
+	pm_runtime_mark_last_busy(twl->dev);
+	pm_runtime_put_sync_suspend(twl->dev);
+	pm_runtime_disable(twl->dev);
+
 	/* autogate 60MHz ULPI clock,
 	 * clear dpll clock request for i2c access,
 	 * disable 32KHz
@@ -772,11 +780,6 @@ static int twl4030_usb_remove(struct platform_device *pdev)
 	/* disable complete OTG block */
 	twl4030_usb_clear_bits(twl, POWER_CTRL, POWER_CTRL_OTG_ENAB);
 
-	if (cable_present(twl->linkstat))
-		pm_runtime_put_noidle(twl->dev);
-	pm_runtime_mark_last_busy(twl->dev);
-	pm_runtime_put(twl->dev);
-
 	return 0;
 }
 
-- 
1.7.9.5