linux-kernel - [PATCH 5/6] twl4030-usb: Don't power down phy when it is in-use by charger.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20120425073311.20124.75294.stgit@notabene.brown>
Date:	Wed, 25 Apr 2012 17:33:11 +1000
From:	NeilBrown <neilb@...e.de>
To:	Samuel Ortiz <sameo@...ux.intel.com>, Felipe Balbi <balbi@...com>,
	Grazvydas Ignotas <notasas@...il.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:	linux-kernel@...r.kernel.org, linux-usb@...r.kernel.org,
	linux-omap@...r.kernel.org, NeilBrown <neilb@...e.de>
Subject: [PATCH 5/6] twl4030-usb: Don't power down phy when it is in-use by
 charger.

The USB phy is used both for data transfer and to charge the battery.
If the charger it active it will hold a reference to
usb3v1.  In that case we don't want to power-down the phy.

This allows charging to continue while the device is suspended.

Signed-off-by: NeilBrown <neilb@...e.de>
---

 drivers/usb/otg/twl4030-usb.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/otg/twl4030-usb.c b/drivers/usb/otg/twl4030-usb.c
index c4a86da..bd8fe9b 100644
--- a/drivers/usb/otg/twl4030-usb.c
+++ b/drivers/usb/otg/twl4030-usb.c
@@ -388,10 +388,16 @@ static void twl4030_phy_power(struct twl4030_usb *twl, int on)
 					(PHY_CLK_CTRL_CLOCKGATING_EN |
 						PHY_CLK_CTRL_CLK32K_EN));
 	} else {
-		__twl4030_phy_power(twl, 0);
 		regulator_disable(twl->usb1v5);
 		regulator_disable(twl->usb1v8);
 		regulator_disable(twl->usb3v1);
+		if (!regulator_is_enabled(twl->usb3v1))
+			/* no-one else is requesting this
+			 * so it is OK to power-down the
+			 * phy.  Sometimes a charger might
+			 * hold the regulator active.
+			 */
+			__twl4030_phy_power(twl, 0);
 	}
 }
 


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/