mmc: esdhc: Add support for 8-bit bus width and non-removable card

This patch adds support of connecting an MMC media using an 8-bit
bus width connection to Freescale's P2020 H/W SDHC controller. During
the probe function, the generic function mmc_of_parse is called to
detect whether the controller is configured with 8-bit bus width.

Also, the generic function detects if the non-removable property is
set in the device tree.  The function esdhc_pltfm_bus_width was added
because the bus width configuration is platform specific.

Signed-off-by: Oded Gabbay <ogabbay@advaoptical.com>
Reviewed-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Oded Gabbay 2013-06-27 12:00:05 -04:00 committed by Chris Ball
parent 7c4f10ac5a
commit 66b50a0099
2 changed files with 50 additions and 1 deletions

View File

@ -36,6 +36,13 @@
/* pltfm-specific */
#define ESDHC_HOST_CONTROL_LE 0x20
/*
* P2020 interpretation of the SDHCI_HOST_CONTROL register
*/
#define ESDHC_CTRL_4BITBUS (0x1 << 1)
#define ESDHC_CTRL_8BITBUS (0x2 << 1)
#define ESDHC_CTRL_BUSWIDTH_MASK (0x3 << 1)
/* OF-specific */
#define ESDHC_DMA_SYSCTL 0x40c
#define ESDHC_DMA_SNOOP 0x00000040

View File

@ -13,6 +13,7 @@
* your option) any later version.
*/
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/delay.h>
@ -230,6 +231,30 @@ static void esdhc_of_platform_init(struct sdhci_host *host)
host->quirks &= ~SDHCI_QUIRK_NO_BUSY_IRQ;
}
static int esdhc_pltfm_bus_width(struct sdhci_host *host, int width)
{
u32 ctrl;
switch (width) {
case MMC_BUS_WIDTH_8:
ctrl = ESDHC_CTRL_8BITBUS;
break;
case MMC_BUS_WIDTH_4:
ctrl = ESDHC_CTRL_4BITBUS;
break;
default:
ctrl = 0;
break;
}
clrsetbits_be32(host->ioaddr + SDHCI_HOST_CONTROL,
ESDHC_CTRL_BUSWIDTH_MASK, ctrl);
return 0;
}
static const struct sdhci_ops sdhci_esdhc_ops = {
.read_l = esdhc_readl,
.read_w = esdhc_readw,
@ -247,6 +272,7 @@ static const struct sdhci_ops sdhci_esdhc_ops = {
.platform_resume = esdhc_of_resume,
#endif
.adma_workaround = esdhci_of_adma_workaround,
.platform_bus_width = esdhc_pltfm_bus_width,
};
static const struct sdhci_pltfm_data sdhci_esdhc_pdata = {
@ -262,7 +288,23 @@ static const struct sdhci_pltfm_data sdhci_esdhc_pdata = {
static int sdhci_esdhc_probe(struct platform_device *pdev)
{
return sdhci_pltfm_register(pdev, &sdhci_esdhc_pdata, 0);
struct sdhci_host *host;
int ret;
host = sdhci_pltfm_init(pdev, &sdhci_esdhc_pdata, 0);
if (IS_ERR(host))
return PTR_ERR(host);
sdhci_get_of_property(pdev);
/* call to generic mmc_of_parse to support additional capabilities */
mmc_of_parse(host->mmc);
ret = sdhci_add_host(host);
if (ret)
sdhci_pltfm_free(pdev);
return ret;
}
static int sdhci_esdhc_remove(struct platform_device *pdev)