mmc: remove multiwrite capability

Relax requirements on host controllers and only require that they do not
report a transfer count than is larger than the actual one (i.e. a lower
value is okay). This is how many other parts of the kernel behaves so
upper layers should already be prepared to handle that scenario. This
gives us a performance boost on MMC cards.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

7 files changed, 6 insertions, 10 deletions

diff --git a/drivers/mmc/host/at91_mci.c b/drivers/mmc/host/at91_mci.c
index 16df235fcc2e..f15e2064305c 100644
--- a/drivers/mmc/host/at91_mci.c
+++ b/drivers/mmc/host/at91_mci.c
@@ -995,7 +995,7 @@ static int __init at91_mci_probe(struct platform_device *pdev)
 	mmc->f_min = 375000;
 	mmc->f_max = 25000000;
 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
-	mmc->caps = MMC_CAP_MULTIWRITE | MMC_CAP_SDIO_IRQ;
+	mmc->caps = MMC_CAP_SDIO_IRQ;
 
 	mmc->max_blk_size = 4095;
 	mmc->max_blk_count = mmc->max_req_size;
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 25d5324ab7e2..cce873c5a149 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -849,7 +849,7 @@ static int __init atmci_probe(struct platform_device *pdev)
 	mmc->f_min = (host->bus_hz + 511) / 512;
 	mmc->f_max = host->bus_hz / 2;
 	mmc->ocr_avail	= MMC_VDD_32_33 | MMC_VDD_33_34;
-	mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_MULTIWRITE;
+	mmc->caps |= MMC_CAP_4_BIT_DATA;
 
 	mmc->max_hw_segs = 64;
 	mmc->max_phys_segs = 64;
diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
index 4e82f64a96bc..41cc63360e43 100644
--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -1252,10 +1252,7 @@ static int mmc_spi_probe(struct spi_device *spi)
 	mmc->ops = &mmc_spi_ops;
 	mmc->max_blk_size = MMC_SPI_BLOCKSIZE;
 
-	/* As long as we keep track of the number of successfully
-	 * transmitted blocks, we're good for multiwrite.
-	 */
-	mmc->caps = MMC_CAP_SPI | MMC_CAP_MULTIWRITE;
+	mmc->caps = MMC_CAP_SPI;
 
 	/* SPI doesn't need the lowspeed device identification thing for
 	 * MMC or SD cards, since it never comes up in open drain mode.
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index da5fecad74d9..696cf3647ceb 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -535,7 +535,6 @@ static int mmci_probe(struct amba_device *dev, void *id)
 	mmc->f_min = (host->mclk + 511) / 512;
 	mmc->f_max = min(host->mclk, fmax);
 	mmc->ocr_avail = plat->ocr_mask;
-	mmc->caps = MMC_CAP_MULTIWRITE;
 
 	/*
 	 * We can do SGIO
diff --git a/drivers/mmc/host/omap.c b/drivers/mmc/host/omap.c
index 549517c35675..dbc26eb6a89e 100644
--- a/drivers/mmc/host/omap.c
+++ b/drivers/mmc/host/omap.c
@@ -1317,7 +1317,7 @@ static int __init mmc_omap_new_slot(struct mmc_omap_host *host, int id)
 
 	host->slots[id] = slot;
 
-	mmc->caps = MMC_CAP_MULTIWRITE;
+	mmc->caps = 0;
 	if (host->pdata->conf.wire4)
 		mmc->caps |= MMC_CAP_4_BIT_DATA;
 
diff --git a/drivers/mmc/host/tifm_sd.c b/drivers/mmc/host/tifm_sd.c
index 1c14a186f000..13844843e8de 100644
--- a/drivers/mmc/host/tifm_sd.c
+++ b/drivers/mmc/host/tifm_sd.c
@@ -973,7 +973,7 @@ static int tifm_sd_probe(struct tifm_dev *sock)
 
 	mmc->ops = &tifm_sd_ops;
 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
-	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_MULTIWRITE;
+	mmc->caps = MMC_CAP_4_BIT_DATA;
 	mmc->f_min = 20000000 / 60;
 	mmc->f_max = 24000000;
 
diff --git a/drivers/mmc/host/wbsd.c b/drivers/mmc/host/wbsd.c
index f7dcd8ec0d7f..adda37952032 100644
--- a/drivers/mmc/host/wbsd.c
+++ b/drivers/mmc/host/wbsd.c
@@ -1219,7 +1219,7 @@ static int __devinit wbsd_alloc_mmc(struct device *dev)
 	mmc->f_min = 375000;
 	mmc->f_max = 24000000;
 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
-	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_MULTIWRITE;
+	mmc->caps = MMC_CAP_4_BIT_DATA;
 
 	spin_lock_init(&host->lock);