aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/mmc/host/mmc_spi.c
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2009-08-15 18:55:58 +0200
committerIngo Molnar <mingo@elte.hu>2009-08-15 18:56:13 +0200
commitfa08661af834875c9bd6f7f0b1b9388dc72a6585 (patch)
treec381fcfcfeb38515bfa93445c80ad9231343414d /drivers/mmc/host/mmc_spi.c
parent240ebbf81f149b11a31e060ebe5ee51a3c775360 (diff)
parent64f1607ffbbc772685733ea63e6f7f4183df1b16 (diff)
downloadkernel_samsung_smdk4412-fa08661af834875c9bd6f7f0b1b9388dc72a6585.zip
kernel_samsung_smdk4412-fa08661af834875c9bd6f7f0b1b9388dc72a6585.tar.gz
kernel_samsung_smdk4412-fa08661af834875c9bd6f7f0b1b9388dc72a6585.tar.bz2
Merge commit 'v2.6.31-rc6' into core/rcu
Merge reason: the branch was on pre-rc1 .30, update to latest. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'drivers/mmc/host/mmc_spi.c')
-rw-r--r--drivers/mmc/host/mmc_spi.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
index 240608c..a461017 100644
--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -1313,6 +1313,12 @@ static int mmc_spi_probe(struct spi_device *spi)
struct mmc_spi_host *host;
int status;
+ /* We rely on full duplex transfers, mostly to reduce
+ * per-transfer overheads (by making fewer transfers).
+ */
+ if (spi->master->flags & SPI_MASTER_HALF_DUPLEX)
+ return -EINVAL;
+
/* MMC and SD specs only seem to care that sampling is on the
* rising edge ... meaning SPI modes 0 or 3. So either SPI mode
* should be legit. We'll use mode 0 since the steady state is 0,