The i.MX esdhc has a nonstandard bit layout for the SDHCI_HOST_CONTROL
register. To support 8bit bus width on i.MX populate the platform_bus_width
callback. This is tested on an i.MX25, but should according to the datasheets
work on the other i.MX using this hardware aswell. The i.MX6, while having
a SDHCI_SPEC_300 controller, still uses the same nonstandard register layout.
Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
---
.../devicetree/bindings/mmc/fsl-imx-esdhc.txt | 1 +
arch/arm/plat-mxc/include/mach/esdhc.h | 1 +
drivers/mmc/host/sdhci-esdhc-imx.c | 56 ++++++++++++++++++--
3 files changed, 55 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
index 1dd6225..c989994 100644
--- a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
+++ b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
@@ -12,6 +12,7 @@ Required properties:
Optional properties:
- fsl,cd-controller : Indicate to use controller internal card detection
- fsl,wp-controller : Indicate to use controller internal write protection
+- bus-width : Maximum supported bus width. Defaults to 4 if omitted
Examples:
diff --git a/arch/arm/plat-mxc/include/mach/esdhc.h b/arch/arm/plat-mxc/include/mach/esdhc.h
index aaf9748..b4a0521 100644
--- a/arch/arm/plat-mxc/include/mach/esdhc.h
+++ b/arch/arm/plat-mxc/include/mach/esdhc.h
@@ -39,5 +39,6 @@ struct esdhc_platform_data {
unsigned int cd_gpio;
enum wp_types wp_type;
enum cd_types cd_type;
+ int max_bus_width;
};
#endif /* __ASM_ARCH_IMX_ESDHC_H */
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 4fe7312..b205fe9 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -57,6 +57,13 @@
*/
#define ESDHC_FLAG_MULTIBLK_NO_INT (1 << 1)
+/*
+ * Freescale interpretation of the SDHCI_HOST_CONTROL register
+ */
+#define FSL_SDHCI_CTRL_4BITBUS (0x1 << 1)
+#define FSL_SDHCI_CTRL_8BITBUS (0x2 << 1)
+#define FSL_SDHCI_CTRL_BUSWIDTH_MASK (0x3 << 1)
+
enum imx_esdhc_type {
IMX25_ESDHC,
IMX35_ESDHC,
@@ -307,6 +314,7 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct pltfm_imx_data *imx_data = pltfm_host->priv;
u32 new_val;
+ u32 mask;
switch (reg) {
case SDHCI_POWER_CONTROL:
@@ -318,7 +326,6 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
case SDHCI_HOST_CONTROL:
/* FSL messed up here, so we can just keep those three */
new_val = val & (SDHCI_CTRL_LED | \
- SDHCI_CTRL_4BITBUS | \
SDHCI_CTRL_D3CD);
/* ensure the endianess */
new_val |= ESDHC_HOST_CONTROL_LE;
@@ -328,7 +335,13 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
new_val |= (val & SDHCI_CTRL_DMA_MASK) << 5;
}
- esdhc_clrset_le(host, 0xffff, new_val, reg);
+ /*
+ * Do not touch buswidth bits here. This is done in
+ * esdhc_pltfm_buswidth.
+ */
+ mask = 0xffff & ~FSL_SDHCI_CTRL_BUSWIDTH_MASK;
+
+ esdhc_clrset_le(host, mask, new_val, reg);
return;
}
esdhc_clrset_le(host, 0xff, val, reg);
@@ -379,6 +392,27 @@ static unsigned int esdhc_pltfm_get_ro(struct sdhci_host *host)
return -ENOSYS;
}
+static int esdhc_pltfm_bus_width(struct sdhci_host *host, int width)
+{
+ u32 ctrl;
+
+ switch (width) {
+ case MMC_BUS_WIDTH_8:
+ ctrl = FSL_SDHCI_CTRL_8BITBUS;
+ break;
+ case MMC_BUS_WIDTH_4:
+ ctrl = FSL_SDHCI_CTRL_4BITBUS;
+ break;
+ default:
+ ctrl = 0;
+ break;
+ }
+
+ esdhc_clrset_le(host, FSL_SDHCI_CTRL_BUSWIDTH_MASK, ctrl, SDHCI_HOST_CONTROL);
+
+ return 0;
+}
+
static struct sdhci_ops sdhci_esdhc_ops = {
.read_l = esdhc_readl_le,
.read_w = esdhc_readw_le,
@@ -389,6 +423,7 @@ static struct sdhci_ops sdhci_esdhc_ops = {
.get_max_clock = esdhc_pltfm_get_max_clock,
.get_min_clock = esdhc_pltfm_get_min_clock,
.get_ro = esdhc_pltfm_get_ro,
+ .platform_bus_width = esdhc_pltfm_bus_width,
};
static struct sdhci_pltfm_data sdhci_esdhc_imx_pdata = {
@@ -434,6 +469,8 @@ sdhci_esdhc_imx_probe_dt(struct platform_device *pdev,
if (gpio_is_valid(boarddata->wp_gpio))
boarddata->wp_type = ESDHC_WP_GPIO;
+ of_property_read_u32(np, "bus-width", &boarddata->max_bus_width);
+
return 0;
}
#else
@@ -507,7 +544,7 @@ static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
if (is_imx25_esdhc(imx_data) || is_imx35_esdhc(imx_data))
/* Fix errata ENGcm07207 present on i.MX25 and i.MX35 */
host->quirks |= SDHCI_QUIRK_NO_MULTIBLOCK
- | SDHCI_QUIRK_BROKEN_ADMA;
+ | SDHCI_QUIRK_BROKEN_ADMA;
if (is_imx53_esdhc(imx_data))
imx_data->flags |= ESDHC_FLAG_MULTIBLK_NO_INT;
@@ -577,6 +614,19 @@ static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
break;
}
+ switch (boarddata->max_bus_width) {
+ case 8:
+ host->mmc->caps |= MMC_CAP_8_BIT_DATA | MMC_CAP_4_BIT_DATA;
+ break;
+ case 4:
+ default:
+ host->mmc->caps |= MMC_CAP_4_BIT_DATA;
+ break;
+ case 1:
+ host->quirks |= SDHCI_QUIRK_FORCE_1_BIT_DATA;
+ break;
+ }
+
err = sdhci_add_host(host);
if (err)
goto err_add_host;
--
1.7.10.4
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
