mmc: Move regulator handling closer to core

After discovering a problem in regulator reference counting I took Mark
Brown's advice to move the reference count into the MMC core by making the
regulator status a member of struct mmc_host.

I took this opportunity to also implement NULL versions of
the regulator functions so as to rid the driver code from
some ugly #ifdef CONFIG_REGULATOR clauses.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Adrian Hunter <adrian.hunter@nokia.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Sundar Iyer <sundar.iyer@stericsson.com>
Cc: Daniel Mack <daniel@caiaq.de>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Cliff Brake <cbrake@bec-systems.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 18 insertions, 10 deletions

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 5f2e72d38b5d..87b4fc6c98c2 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -523,19 +523,27 @@ static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
         struct mmci_host *host = mmc_priv(mmc);
         u32 pwr = 0;
         unsigned long flags;
+        int ret;
 
         switch (ios->power_mode) {
         case MMC_POWER_OFF:
-                if(host->vcc &&
-                   regulator_is_enabled(host->vcc))
-                        regulator_disable(host->vcc);
+                if (host->vcc)
+                        ret = mmc_regulator_set_ocr(mmc, host->vcc, 0);
                 break;
         case MMC_POWER_UP:
-#ifdef CONFIG_REGULATOR
-                if (host->vcc)
-                        /* This implicitly enables the regulator */
-                        mmc_regulator_set_ocr(host->vcc, ios->vdd);
-#endif
+                if (host->vcc) {
+                        ret = mmc_regulator_set_ocr(mmc, host->vcc, ios->vdd);
+                        if (ret) {
+                                dev_err(mmc_dev(mmc), "unable to set OCR\n");
+                                /*
+                                 * The .set_ios() function in the mmc_host_ops
+                                 * struct return void, and failing to set the
+                                 * power should be rare so we print an error
+                                 * and return here.
+                                 */
+                                return;
+                        }
+                }
                 if (host->plat->vdd_handler)
                         pwr |= host->plat->vdd_handler(mmc_dev(mmc), ios->vdd,
                                                        ios->power_mode);
@@ -869,8 +877,8 @@ static int __devexit mmci_remove(struct amba_device *dev)
                 clk_disable(host->clk);
                 clk_put(host->clk);
 
-                if (regulator_is_enabled(host->vcc))
-                        regulator_disable(host->vcc);
+                if (host->vcc)
+                        mmc_regulator_set_ocr(mmc, host->vcc, 0);
                 regulator_put(host->vcc);
 
                 mmc_free_host(mmc);