Re: [Sdhci-devel] [PATCH 2.6.20-rc2] Add a quirk to allow ENE PCI SD card readers to work again

[Pierre Ossman <drzeus-mmc@drzeus.cx>]

Hi Darren,

It has come to my attention that the current routine for setting power
is not compliant with the specification. As such, I'd like you to try
the following and see if removes the need for your patch:

diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index dc1b04a..13ac2fe 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -685,23 +690,21 @@ static void sdhci_set_power(struct sdhci_host
*host, unsigned short power)
        if (power == (unsigned short)-1)
                goto out;

-       pwr = SDHCI_POWER_ON;
-
        switch (power) {
        case MMC_VDD_170:
        case MMC_VDD_180:
        case MMC_VDD_190:
-               pwr |= SDHCI_POWER_180;
+               pwr = SDHCI_POWER_180;
                break;
        case MMC_VDD_290:
        case MMC_VDD_300:
        case MMC_VDD_310:
-               pwr |= SDHCI_POWER_300;
+               pwr = SDHCI_POWER_300;
                break;
        case MMC_VDD_320:
        case MMC_VDD_330:
        case MMC_VDD_340:
-               pwr |= SDHCI_POWER_330;
+               pwr = SDHCI_POWER_330;
                break;
        default:
                BUG();
@@ -709,6 +712,10 @@ static void sdhci_set_power(struct sdhci_host
*host, unsigned short power)

        writeb(pwr, host->ioaddr + SDHCI_POWER_CONTROL);

+       pwr |= SDHCI_POWER_ON;
+
+       writeb(pwr, host->ioaddr + SDHCI_POWER_CONTROL);
+
 out:
        host->power = power;
 }


I'd appreciate if you could test this sooner rather than later as the
merge window is just around the corner.

Rgds
-- 
     -- Pierre Ossman

  Linux kernel, MMC maintainer        http://www.kernel.org
  PulseAudio, core developer          http://pulseaudio.org
  rdesktop, core developer          http://www.rdesktop.org