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, 16 insertions, 10 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index c5e3c9bf6fdd..46029d5c0364 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -772,8 +772,9 @@ EXPORT_SYMBOL(mmc_regulator_get_ocrmask);
 
 /**
  * mmc_regulator_set_ocr - set regulator to match host->ios voltage
- * @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
+ * @mmc: the host to regulate
  * @supply: regulator to use
+ * @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
  *
  * Returns zero on success, else negative errno.
  *
@@ -781,15 +782,12 @@ EXPORT_SYMBOL(mmc_regulator_get_ocrmask);
  * a particular supply voltage.  This would normally be called from the
  * set_ios() method.
  */
-int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit)
+int mmc_regulator_set_ocr(struct mmc_host *mmc,
+			struct regulator *supply,
+			unsigned short vdd_bit)
 {
 	int			result = 0;
 	int			min_uV, max_uV;
-	int			enabled;
-
-	enabled = regulator_is_enabled(supply);
-	if (enabled < 0)
-		return enabled;
 
 	if (vdd_bit) {
 		int		tmp;
@@ -820,17 +818,25 @@ int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit)
 		else
 			result = 0;
 
-		if (result == 0 && !enabled)
+		if (result == 0 && !mmc->regulator_enabled) {
 			result = regulator_enable(supply);
-	} else if (enabled) {
+			if (!result)
+				mmc->regulator_enabled = true;
+		}
+	} else if (mmc->regulator_enabled) {
 		result = regulator_disable(supply);
+		if (result == 0)
+			mmc->regulator_enabled = false;
 	}
 
+	if (result)
+		dev_err(mmc_dev(mmc),
+			"could not set regulator OCR (%d)\n", result);
 	return result;
 }
 EXPORT_SYMBOL(mmc_regulator_set_ocr);
 
-#endif
+#endif /* CONFIG_REGULATOR */
 
 /*
  * Mask off any voltages we don't support and select