MMC: regulator utilities

Glue between MMC and regulator stacks ... verified with some OMAP3 boards using adjustable and configured-as-fixed regulators on several MMC controllers. These calls are intended to be used by MMC host adapters using at least one regulator per host. Examples include slots with regulators supporting multiple voltages and ones using multiple voltage rails (e.g. DAT4..DAT7 using a separate supply, or a split rail chip like certain SDIO WLAN or eMMC solutions). Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Pierre Ossman <drzeus@drzeus.cx> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

MMC: regulator utilities
Glue between MMC and regulator stacks ... verified with some OMAP3 boards using adjustable and configured-as-fixed regulators on several MMC controllers. These calls are intended to be used by MMC host adapters using at least one regulator per host. Examples include slots with regulators supporting multiple voltages and ones using multiple voltage rails (e.g. DAT4..DAT7 using a separate supply, or a split rail chip like certain SDIO WLAN or eMMC solutions). Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Pierre Ossman <drzeus@drzeus.cx> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
David Brownell · Liam Girdwood
1 parent 66b659e685
Showing 2 changed files with 105 additions and 0 deletions Side-by-side Diff
drivers/mmc/core/core.c
include/linux/mmc/host.h
@@ -21,6 +21,7 @@
 #include <linux/leds.h>
 #include <linux/scatterlist.h>
 #include <linux/log2.h>
+#include <linux/regulator/consumer.h>
  
 #include <linux/mmc/card.h>
 #include <linux/mmc/host.h>
@@ -522,6 +523,105 @@
 	return mask;
 }
 EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
+
+#ifdef CONFIG_REGULATOR
+
+/**
+ * mmc_regulator_get_ocrmask - return mask of supported voltages
+ * @supply: regulator to use
+ *
+ * This returns either a negative errno, or a mask of voltages that
+ * can be provided to MMC/SD/SDIO devices using the specified voltage
+ * regulator.  This would normally be called before registering the
+ * MMC host adapter.
+ */
+int mmc_regulator_get_ocrmask(struct regulator *supply)
+{
+	int			result = 0;
+	int			count;
+	int			i;
+
+	count = regulator_count_voltages(supply);
+	if (count < 0)
+		return count;
+
+	for (i = 0; i < count; i++) {
+		int		vdd_uV;
+		int		vdd_mV;
+
+		vdd_uV = regulator_list_voltage(supply, i);
+		if (vdd_uV <= 0)
+			continue;
+
+		vdd_mV = vdd_uV / 1000;
+		result |= mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
+	}
+
+	return result;
+}
+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)
+ * @supply: regulator to use
+ *
+ * Returns zero on success, else negative errno.
+ *
+ * MMC host drivers may use this to enable or disable a regulator using
+ * 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			result = 0;
+	int			min_uV, max_uV;
+	int			enabled;
+
+	enabled = regulator_is_enabled(supply);
+	if (enabled < 0)
+		return enabled;
+
+	if (vdd_bit) {
+		int		tmp;
+		int		voltage;
+
+		/* REVISIT mmc_vddrange_to_ocrmask() may have set some
+		 * bits this regulator doesn't quite support ... don't
+		 * be too picky, most cards and regulators are OK with
+		 * a 0.1V range goof (it's a small error percentage).
+		 */
+		tmp = vdd_bit - ilog2(MMC_VDD_165_195);
+		if (tmp == 0) {
+			min_uV = 1650 * 1000;
+			max_uV = 1950 * 1000;
+		} else {
+			min_uV = 1900 * 1000 + tmp * 100 * 1000;
+			max_uV = min_uV + 100 * 1000;
+		}
+
+		/* avoid needless changes to this voltage; the regulator
+		 * might not allow this operation
+		 */
+		voltage = regulator_get_voltage(supply);
+		if (voltage < 0)
+			result = voltage;
+		else if (voltage < min_uV || voltage > max_uV)
+			result = regulator_set_voltage(supply, min_uV, max_uV);
+		else
+			result = 0;
+
+		if (result == 0 && !enabled)
+			result = regulator_enable(supply);
+	} else if (enabled) {
+		result = regulator_disable(supply);
+	}
+
+	return result;
+}
+EXPORT_SYMBOL(mmc_regulator_set_ocr);
+
+#endif
  
 /*
  * Mask off any voltages we don't support and select
@@ -192,5 +192,10 @@
 	wake_up_process(host->sdio_irq_thread);
 }
  
+struct regulator;
+
+int mmc_regulator_get_ocrmask(struct regulator *supply);
+int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit);
+
 #endif
...	...	@@ -21,6 +21,7 @@
21	21	#include <linux/leds.h>
22	22	#include <linux/scatterlist.h>
23	23	#include <linux/log2.h>
	24	+#include <linux/regulator/consumer.h>
24	25
25	26	#include <linux/mmc/card.h>
26	27	#include <linux/mmc/host.h>
...	...	@@ -522,6 +523,105 @@
522	523	return mask;
523	524	}
524	525	EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
	526	+
	527	+#ifdef CONFIG_REGULATOR
	528	+
	529	+/**
	530	+ * mmc_regulator_get_ocrmask - return mask of supported voltages
	531	+ * @supply: regulator to use
	532	+ *
	533	+ * This returns either a negative errno, or a mask of voltages that
	534	+ * can be provided to MMC/SD/SDIO devices using the specified voltage
	535	+ * regulator. This would normally be called before registering the
	536	+ * MMC host adapter.
	537	+ */
	538	+int mmc_regulator_get_ocrmask(struct regulator *supply)
	539	+{
	540	+ int result = 0;
	541	+ int count;
	542	+ int i;
	543	+
	544	+ count = regulator_count_voltages(supply);
	545	+ if (count < 0)
	546	+ return count;
	547	+
	548	+ for (i = 0; i < count; i++) {
	549	+ int vdd_uV;
	550	+ int vdd_mV;
	551	+
	552	+ vdd_uV = regulator_list_voltage(supply, i);
	553	+ if (vdd_uV <= 0)
	554	+ continue;
	555	+
	556	+ vdd_mV = vdd_uV / 1000;
	557	+ result \|= mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
	558	+ }
	559	+
	560	+ return result;
	561	+}
	562	+EXPORT_SYMBOL(mmc_regulator_get_ocrmask);
	563	+
	564	+/**
	565	+ * mmc_regulator_set_ocr - set regulator to match host->ios voltage
	566	+ * @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
	567	+ * @supply: regulator to use
	568	+ *
	569	+ * Returns zero on success, else negative errno.
	570	+ *
	571	+ * MMC host drivers may use this to enable or disable a regulator using
	572	+ * a particular supply voltage. This would normally be called from the
	573	+ * set_ios() method.
	574	+ */
	575	+int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit)
	576	+{
	577	+ int result = 0;
	578	+ int min_uV, max_uV;
	579	+ int enabled;
	580	+
	581	+ enabled = regulator_is_enabled(supply);
	582	+ if (enabled < 0)
	583	+ return enabled;
	584	+
	585	+ if (vdd_bit) {
	586	+ int tmp;
	587	+ int voltage;
	588	+
	589	+ /* REVISIT mmc_vddrange_to_ocrmask() may have set some
	590	+ * bits this regulator doesn't quite support ... don't
	591	+ * be too picky, most cards and regulators are OK with
	592	+ * a 0.1V range goof (it's a small error percentage).
	593	+ */
	594	+ tmp = vdd_bit - ilog2(MMC_VDD_165_195);
	595	+ if (tmp == 0) {
	596	+ min_uV = 1650 * 1000;
	597	+ max_uV = 1950 * 1000;
	598	+ } else {
	599	+ min_uV = 1900 * 1000 + tmp * 100 * 1000;
	600	+ max_uV = min_uV + 100 * 1000;
	601	+ }
	602	+
	603	+ /* avoid needless changes to this voltage; the regulator
	604	+ * might not allow this operation
	605	+ */
	606	+ voltage = regulator_get_voltage(supply);
	607	+ if (voltage < 0)
	608	+ result = voltage;
	609	+ else if (voltage < min_uV \|\| voltage > max_uV)
	610	+ result = regulator_set_voltage(supply, min_uV, max_uV);
	611	+ else
	612	+ result = 0;
	613	+
	614	+ if (result == 0 && !enabled)
	615	+ result = regulator_enable(supply);
	616	+ } else if (enabled) {
	617	+ result = regulator_disable(supply);
	618	+ }
	619	+
	620	+ return result;
	621	+}
	622	+EXPORT_SYMBOL(mmc_regulator_set_ocr);
	623	+
	624	+#endif
525	625
526	626	/*
527	627	* Mask off any voltages we don't support and select
...	...	@@ -192,5 +192,10 @@
192	192	wake_up_process(host->sdio_irq_thread);
193	193	}
194	194
	195	+struct regulator;
	196	+
	197	+int mmc_regulator_get_ocrmask(struct regulator *supply);
	198	+int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit);
	199	+
195	200	#endif