How to enable SPI mode for SDIO in galileo gen 2...?

[BArde]

Hi,

For SDIO there are three modes of operation,

1) 1 bit mode

2) 4 bit mode

3) spi mode

i am able to switch between 1 bit mode and 4 bit mode using quirks_debug value passing with sdhci driver module.but i am not getting how to switch in SPI mode there are no bit are available in driver for setting it to SPI mode. so how to switch in SPI mode ?

[asss · Accepted solution]

Hi,

as I see sdhci driver does not support SPI mode. Need to rewrite a driver.

BR,

xbolshe

[BArde]

Hi xbolshe

I am seeing that if i am able to disable 1 bit mode and 4 bit mode for SDIO then it will work as SPI mode so i am able to disable 1 bit mode using http://lxr.free-electrons.com/ident?i=SDHCI_QUIRK_FORCE_1_BIT_DATA QUIRK_FORCE_1_BIT_DATA bit in sdhci driver but how to disable 4 bit mode...????

[asss]

Hi Bhautik_Ardeshana,

take a look at http://lxr.free-electrons.com/source/drivers/mmc/host/sdhci.c?v=3.8# L2848 http://lxr.free-electrons.com/source/drivers/mmc/host/sdhci.c?v=3.8# L2848

if (!(http://lxr.free-electrons.com/ident?v=3.8;i=host host->http://lxr.free-electrons.com/ident?v=3.8;i=quirks quirks & http://lxr.free-electrons.com/ident?v=3.8;i=SDHCI_QUIRK_FORCE_1_BIT_DATA SDHCI_QUIRK_FORCE_1_BIT_DATA))

http://lxr.free-electrons.com/ident?v=3.8;i=mmc mmc->caps |= http://lxr.free-electrons.com/ident?v=3.8;i=MMC_CAP_4_BIT_DATA MMC_CAP_4_BIT_DATA;

4 bit mode is enabled, when http://lxr.free-electrons.com/ident?i=SDHCI_QUIRK_FORCE_1_BIT_DATA QUIRK_FORCE_1_BIT_DATA = 0.

There is no way to disable 4 bit mode except http://lxr.free-electrons.com/ident?i=SDHCI_QUIRK_FORCE_1_BIT_DATA QUIRK_FORCE_1_BIT_DATA as well as no way to enable SPI mode, because it is not implemented in sdhci driver.

BR,

xbolshe