About the get_cd callback function

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Hi all,
I just posted three patches to use get_cd to detect the card (somebody has saw them, But I didn't receive them from Linux-mmc, I don't know why):
[PATCH 1/3] SDHCI: add sdhci_get_cd callback to detect the card
[PATCH 2/3] MMC/SD: add callback function to detect card
[PATCH 3/3] SDHC/MMC: add f_min to mmc_power_on

I had posted them last year, but them were not accepted :(
Now I will express my reason to add this function and welcome give your comment.

"mmc_send_status" (that is used to check if the card has been removed, in file sd.c and mmc.c) will timeout when there is not SD/MMC card in slot, system will generate too many interrupts; even if the SD/MMC card present, there will generate many interrupts to return the card status from the SD/MMC card. Which will downgrade the performance of the system because system will take many time to handle these interrupts.
Therefore, I use the callback function "get_cd" to read the Present State register and check the bit CINS, if the SD card present, which will be 1, otherwise it will be 0.


Thanks and Best Regards
Jerry Huang



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