On Tuesday, April 16, 2013, Doug Anderson > Seungwon, > > On Mon, Apr 15, 2013 at 5:14 AM, Seungwon Jeon <tgih.jun@xxxxxxxxxxx> wrote: > >> + MMC_CAP_8_BIT_DATA | MMC_CAP_CMD23 | MMC_CAP_SDIO_IRQ, > >> + MMC_CAP_CMD23 | MMC_CAP_SDIO_IRQ, > > This line for [1] > >> + MMC_CAP_CMD23 | MMC_CAP_SDIO_IRQ, > >> + MMC_CAP_CMD23 | MMC_CAP_SDIO_IRQ, > > [1] is for mshc1. mshc1 is only used for SDIO. > > As I know, The others are improper for SDIO. > > I'm nearly certain that all of the ports are OK for SDIO. Specifically: > > * On the ARM Chromebook (exynos5250) we are using mmc3 (12230000) for > the SDIO connection to WiFi. > > * I have plugged in an external WiFi module to the SD card slot on the > ARM Chromebook and seen it work (including interrupts). This is mmc2 > (12220000). Yes, we also have tested WiFi module type of sd slot with ch#2. > > * I have seen a board where mmc1 was wired up to WiFi and seen it work. Yes, mmc2, mmc3 can > > > It is possible that mmc0 wouldn't work for SDIO. I've never tested it > since mmc0 is intended for eMMC and every system I've worked with has > eMMC on that port. There is some evidence that mmc0 would work for > SDIO, though: there is a muxing slot on GPC0[2] for SD_0_CARD_INT_n. > That implies that mmc0 ought to also work for SDIO (and even could be > configured for an external eSDIO interrupt, I guess). I don't mean that SDIO is impossible except in ch#1. Basically, SDIO device can be attached on all host's channel and may works. In case of ch#0, it's almost dedicated for eMMC and is actually arranged for eMMC. And ch#1 is recommended for SDIO and can support UHS-I speed. So, I don't think MMC_CAP_SDIO_IRQ is needed to ch#0. Similarly, MMC_CAP_SDIO_IRQ is not a good choice for ch#2, ch#3 by default. If needed for specific channel, it can be got from dts as property. if (of_find_property(np, "cap-sdio-irq", NULL)) pdata->caps |= MMC_CAP_SDIO_IRQ; Thanks, Seungwon Jeon > > > Thanks! > > -Doug -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
