about MMC0 CD pin,is it neccesarry?

Hi,

You will probably need to modify your code so that the CD status is either ignored or interpreted as card present.

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ａｓ　Ｉ　ｋｎｏｗ，ＭＭＣ　ｃｏｕｌｄ　ｄｅｔｅｃｔ　ｂｙ　ＤＡＴ１　ｐｉｎ？

Hi, 

Check mmc_detect() & mmc_init_card() functions in drivers/mmc/core/mmc.c AND mmc_sdio_detect() & mmc_sdio_init_card() fucntions in drivers/mmc/core/sdio.c 

Amon Wu said:

ａｓ　Ｉ　ｋｎｏｗ，ＭＭＣ　ｃｏｕｌｄ　ｄｅｔｅｃｔ　ｂｙ　ＤＡＴ１　ｐｉｎ？

DAT1 pin can be used as IRQ and data pin, see Figre MMCHS Module SDIO Application, Figure MMCHS SD (4-bit) Card Application and Figure MMCHS Module MMC Application in AM335x TRM. 

DAT3 pin however can be used as CD signal in mmchs sd (4-bit) card application

Hope this helps. 

Best Regards, 

Yordan

In the 3.2 kernel you should be able to edit the arch/arm/mach-omap2/board-am335xevm.c file and modify the am335x_mmc strucure and change gpio_cd and gpio_wp to -EINVAL:

 212 static struct omap2_hsmmc_info am335x_mmc[] __initdata = {
 213         {
 214                 .mmc            = 1,
 215                 .caps           = MMC_CAP_4_BIT_DATA,
 216                 .gpio_cd        = -EINVAL,
 217                 .gpio_wp        = -EINVAL,
 218                 .ocr_mask       = MMC_VDD_32_33 | MMC_VDD_33_34, /* 3V3 */
 219         },

Steve K.

Hi steven many thanks