[PATCH] mmc: core: Add a capability for disabling mmc cards

From: Adam Lee
Date: Tue May 14 2013 - 03:37:44 EST


On some systems we need a way to disable MMC card support in a MMC/SD
card slot due to the legal concern.

Add support in the core SD/MMC code to support this.

Signed-off-by: Doug Anderson <dianders@xxxxxxxxxxxx>
Signed-off-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>
Signed-off-by: Adam Lee <adam.lee@xxxxxxxxxxxxx>
---
drivers/mmc/core/core.c | 2 +-
include/linux/mmc/host.h | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index c40396f..4788b88 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2271,7 +2271,7 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
return 0;
if (!mmc_attach_sd(host))
return 0;
- if (!mmc_attach_mmc(host))
+ if (!(host->caps2 & MMC_CAP2_NO_MMC) && !mmc_attach_mmc(host))
return 0;

mmc_power_off(host);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index e326ae2..ffe5c3d 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -281,6 +281,7 @@ struct mmc_host {
#define MMC_CAP2_PACKED_CMD (MMC_CAP2_PACKED_RD | \
MMC_CAP2_PACKED_WR)
#define MMC_CAP2_NO_PRESCAN_POWERUP (1 << 14) /* Don't power up before scan */
+#define MMC_CAP2_NO_MMC (1 << 15) /* Only SD supported, not MMC */

mmc_pm_flag_t pm_caps; /* supported pm features */

--
1.7.10.4

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