[4.2.y-ckt stable] Patch "mmc: sdhci-pci: Do not default to 33 Ohm driver strength for Intel SPT" has been added to the 4.2.y-ckt tree
Kamal Mostafa
kamal at canonical.com
Wed Jan 27 00:10:14 UTC 2016
This is a note to let you know that I have just added a patch titled
mmc: sdhci-pci: Do not default to 33 Ohm driver strength for Intel SPT
to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree
which can be found at:
http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-4.2.y-queue
This patch is scheduled to be released in version 4.2.8-ckt3.
If you, or anyone else, feels it should not be added to this tree, please
reply to this email.
For more information about the 4.2.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable
Thanks.
-Kamal
---8<------------------------------------------------------------
>From 880d16f3815371b418a5bd8e6a30285ba7ab4b42 Mon Sep 17 00:00:00 2001
From: Adrian Hunter <adrian.hunter at intel.com>
Date: Thu, 26 Nov 2015 14:00:45 +0200
Subject: mmc: sdhci-pci: Do not default to 33 Ohm driver strength for Intel
SPT
commit 1ca896856281d3f1ad4f6f7d4e32e2943452de23 upstream.
In some cases, the stronger 33 Ohm driver strength must not be used
so it is not a suitable default. Change it to the standard default
50 Ohm value.
The patch applies to v4.2+ except the file name changed. It is
drivers/mmc/host/sdhci-pci.c prior to v.4.4.
Signed-off-by: Adrian Hunter <adrian.hunter at intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
drivers/mmc/host/sdhci-pci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index b3b0a3e..5d2e222 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -277,7 +277,7 @@ static int spt_select_drive_strength(struct sdhci_host *host,
if (sdhci_pci_spt_drive_strength > 0)
drive_strength = sdhci_pci_spt_drive_strength & 0xf;
else
- drive_strength = 1; /* 33-ohm */
+ drive_strength = 0; /* Default 50-ohm */
if ((mmc_driver_type_mask(drive_strength) & card_drv) == 0)
drive_strength = 0; /* Default 50-ohm */
--
1.9.1
More information about the kernel-team
mailing list