How do you access MMC driver set_ios?
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Hi, this post was originally made on gumstix-users@xxxxxxxxxxxxxxxxxxxxx, but it concerns the MMC stack for PXA270. I hope someone here at the source can help me: What is the accepted method for getting to the mmc_set_ios() method? I want to lower the Verdex Pro MMC clock by passing in a nonstandard clock rate. The pxamci driver refreshes the CLKRT register from the stored value on each pxamci_start_cmd(), which chains from mmc_start_request(). It looks like you have to compute your desired clock rate by dividing the max clock by a power of two between 0 and 6. You then pass that value in to mmc_set_ios(), using an mmc_ios structure, and let pxamci_set_ios() reverse the computation. The end result is a three bit number in CLKRT. I have looked for a command line interface in /proc and /sys with no success. I am currently looking at modprobe with parameters and eventually a C program, but would be very grateful if someone would share a command line access method. Related Posts: http://old.nabble.com/slowing-down-MMC-clock-on-Verdex-Pro--to29765291.html#a29765291 http://old.nabble.com/Sporadic-SD---MMC-failure-to28603343.html -- Larry Martin www.GlueLogix.com _______________________________________________ linux-arm mailing list linux-arm@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/linux-arm
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