tmio_mmc: Prevents unexpected status clear

Commit Message

Matt Fleming Aug. 26, 2010, 10:10 p.m. UTC

None

Patch

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index ee7d0a5..3eabd91 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -657,11 +657,15 @@  static void tmio_mmc_release_dma(struct tmio_mmc_host *host)
 static int tmio_mmc_start_data(struct tmio_mmc_host *host,
 	struct mmc_data *data)
 {
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
+
 	pr_debug("setup data transfer: blocksize %08x  nr_blocks %d\n",
 		 data->blksz, data->blocks);
 
 	/* Hardware cannot perform 1 and 2 byte requests in 4 bit mode */
-	if (data->blksz < 4 && host->mmc->ios.bus_width == MMC_BUS_WIDTH_4) {
+	if (data->blksz < 4 && !(pdata->flags & TMIO_MMC_2BYTE_BLKSZ) &&
+	    host->mmc->ios.bus_width == MMC_BUS_WIDTH_4) {
 		pr_err("%s: %d byte block unsupported in 4 bit mode\n",
 		       mmc_hostname(host->mmc), data->blksz);
 		return -EINVAL;
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index f07425b..56467cb 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -52,6 +52,11 @@ 
 
 /* tmio MMC platform flags */
 #define TMIO_MMC_WRPROTECT_DISABLE	(1 << 0)
+/*
+ * Some controllers can support a 2-byte block size when the bus width
+ * is configured in 4-bit mode.
+ */
+#define TMIO_MMC_2BYTE_BLKSZ		(1 << 1)
 
 int tmio_core_mmc_enable(void __iomem *cnf, int shift, unsigned long base);
 int tmio_core_mmc_resume(void __iomem *cnf, int shift, unsigned long base);


Magnus, since people have tested 2-byte blksz transfers on SDHI and it
works, does it make sense to have this change to
drivers/mfd/sh_mobile_sdhi.c? Are you aware of a version of the SDHI
block that doens't support this mode?

diff --git a/drivers/mfd/sh_mobile_sdhi.c b/drivers/mfd/sh_mobile_sdhi.c
index cd16459..1f3a1b1 100644
--- a/drivers/mfd/sh_mobile_sdhi.c
+++ b/drivers/mfd/sh_mobile_sdhi.c
@@ -112,6 +112,12 @@  static int __init sh_mobile_sdhi_probe(struct platform_device *pdev)
 		mmc_data->ocr_mask = p->tmio_ocr_mask;
 	}
 
+	/*
+	 * All SDHI blocks support 2-byte and larger block sizes in 4-bit
+	 * bus width mode.
+	 */
+	mmc_data->flags |= TMIO_MMC_2BYTE_BLKSZ;
+
 	if (p && p->dma_slave_tx >= 0 && p->dma_slave_rx >= 0) {
 		priv->param_tx.slave_id = p->dma_slave_tx;
 		priv->param_rx.slave_id = p->dma_slave_rx;