mmc: sdhci-pxa: add platform code for UHS signaling

Marvell controller requires 1.8V bit in UHS control register 2
be set when doing UHS.  eMMC does not require 1.8V for DDR.
add platform code to handle this.

Signed-off-by: Philip Rakity <prakity@marvell.com>
Reviewed-by: Arindam Nath <arindam.nath@amd.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Philip Rakity 2011-05-13 11:17:16 +05:30 committed by Chris Ball
parent 6322cdd0eb
commit 756515c626

View File

@ -69,7 +69,45 @@ static void set_clock(struct sdhci_host *host, unsigned int clock)
}
}
static int set_uhs_signaling(struct sdhci_host *host, unsigned int uhs)
{
u16 ctrl_2;
/*
* Set V18_EN -- UHS modes do not work without this.
* does not change signaling voltage
*/
ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
/* Select Bus Speed Mode for host */
ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
switch (uhs) {
case MMC_TIMING_UHS_SDR12:
ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
break;
case MMC_TIMING_UHS_SDR25:
ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
break;
case MMC_TIMING_UHS_SDR50:
ctrl_2 |= SDHCI_CTRL_UHS_SDR50 | SDHCI_CTRL_VDD_180;
break;
case MMC_TIMING_UHS_SDR104:
ctrl_2 |= SDHCI_CTRL_UHS_SDR104 | SDHCI_CTRL_VDD_180;
break;
case MMC_TIMING_UHS_DDR50:
ctrl_2 |= SDHCI_CTRL_UHS_DDR50 | SDHCI_CTRL_VDD_180;
break;
}
sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
pr_debug("%s:%s uhs = %d, ctrl_2 = %04X\n",
__func__, mmc_hostname(host->mmc), uhs, ctrl_2);
return 0;
}
static struct sdhci_ops sdhci_pxa_ops = {
.set_uhs_signaling = set_uhs_signaling,
.set_clock = set_clock,
};
@ -141,6 +179,9 @@ static int __devinit sdhci_pxa_probe(struct platform_device *pdev)
if (pdata->quirks)
host->quirks |= pdata->quirks;
/* enable 1/8V DDR capable */
host->mmc->caps |= MMC_CAP_1_8V_DDR;
/* If slot design supports 8 bit data, indicate this to MMC. */
if (pdata->flags & PXA_FLAG_SD_8_BIT_CAPABLE_SLOT)
host->mmc->caps |= MMC_CAP_8_BIT_DATA;