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| author | Anton Vorontsov <avorontsov@ru.mvista.com> | 2009-06-18 00:14:08 +0400 |
|---|---|---|
| committer | Pierre Ossman <pierre@ossman.eu> | 2009-06-21 21:00:59 +0200 |
| commit | 5fe23c7f51def59f66bc6aeee988ef1a467a2c8c (patch) | |
| tree | 6d10aa3966cf105a8c6d6b758660fa6f00a49896 | |
| parent | 04ac2f46d6ecb995f78c9ae4e2e4707d00b5339f (diff) | |
| download | linux-5fe23c7f51def59f66bc6aeee988ef1a467a2c8c.tar.gz linux-5fe23c7f51def59f66bc6aeee988ef1a467a2c8c.tar.bz2 linux-5fe23c7f51def59f66bc6aeee988ef1a467a2c8c.zip | |
sdhci: Add support for hosts that are only capable of 1-bit transfers
Some hosts (hardware configurations, or particular SD/MMC slots) may
not support 4-bit bus. For example, on MPC8569E-MDS boards we can
switch between serial (1-bit only) and nibble (4-bit) modes, thought
we have to disable more peripherals to work in 4-bit mode.
Along with some small core changes, this patch modifies sdhci-of
driver, so that now it looks for "sdhci,1-bit-only" property in the
device-tree, and if specified we enable a proper quirk.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>
| -rw-r--r-- | Documentation/powerpc/dts-bindings/fsl/esdhc.txt | 2 | ||||
| -rw-r--r-- | drivers/mmc/host/sdhci-of.c | 3 | ||||
| -rw-r--r-- | drivers/mmc/host/sdhci.c | 5 | ||||
| -rw-r--r-- | drivers/mmc/host/sdhci.h | 2 |
4 files changed, 11 insertions, 1 deletions
diff --git a/Documentation/powerpc/dts-bindings/fsl/esdhc.txt b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt index 5093ddf900da..3ed3797b5086 100644 --- a/Documentation/powerpc/dts-bindings/fsl/esdhc.txt +++ b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt @@ -10,6 +10,8 @@ Required properties: - interrupts : should contain eSDHC interrupt. - interrupt-parent : interrupt source phandle. - clock-frequency : specifies eSDHC base clock frequency. + - sdhci,1-bit-only : (optional) specifies that a controller can + only handle 1-bit data transfers. Example: diff --git a/drivers/mmc/host/sdhci-of.c b/drivers/mmc/host/sdhci-of.c index 128c614d11aa..d79fa55c3b89 100644 --- a/drivers/mmc/host/sdhci-of.c +++ b/drivers/mmc/host/sdhci-of.c @@ -250,6 +250,9 @@ static int __devinit sdhci_of_probe(struct of_device *ofdev, host->ops = &sdhci_of_data->ops; } + if (of_get_property(np, "sdhci,1-bit-only", NULL)) + host->quirks |= SDHCI_QUIRK_FORCE_1_BIT_DATA; + clk = of_get_property(np, "clock-frequency", &size); if (clk && size == sizeof(*clk) && *clk) of_host->clock = *clk; diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 3856669aa7e8..c7586739be1e 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1761,7 +1761,10 @@ int sdhci_add_host(struct sdhci_host *host) mmc->ops = &sdhci_ops; mmc->f_min = host->max_clk / 256; mmc->f_max = host->max_clk; - mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ; + mmc->caps = MMC_CAP_SDIO_IRQ; + + if (!(host->quirks & SDHCI_QUIRK_FORCE_1_BIT_DATA)) + mmc->caps |= MMC_CAP_4_BIT_DATA; if (caps & SDHCI_CAN_DO_HISPD) mmc->caps |= MMC_CAP_SD_HIGHSPEED; diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index 84d149096f0e..5d37dd94b53f 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -228,6 +228,8 @@ struct sdhci_host { #define SDHCI_QUIRK_FORCE_BLK_SZ_2048 (1<<20) /* Controller cannot do multi-block transfers */ #define SDHCI_QUIRK_NO_MULTIBLOCK (1<<21) +/* Controller can only handle 1-bit data transfers */ +#define SDHCI_QUIRK_FORCE_1_BIT_DATA (1<<22) int irq; /* Device IRQ */ void __iomem * ioaddr; /* Mapped address */ |