twl4030_charger: Allow charger to control the regulator that feeds it

The charger needs usb3v1 to be running, so add a new consumer to
keep it running.

This allows the charger to draw current even when the USB driver has
powered down.
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>

drivers/mfd/twl-core.c

@@ -716,8 +716,9 @@ add_children(struct twl4030_platform_data *pdata, unsigned irq_base,
 		static struct regulator_consumer_supply usb1v8 = {
 			.supply =	"usb1v8",
 		};
-		static struct regulator_consumer_supply usb3v1 = {
-			.supply =	"usb3v1",
+		static struct regulator_consumer_supply usb3v1[] = {
+			{ .supply =	"usb3v1" },
+			{ .supply =	"bci3v1" },
 		};
 
 	/* First add the regulators so that they can be used by transceiver */
@@ -745,7 +746,7 @@ add_children(struct twl4030_platform_data *pdata, unsigned irq_base,
 				return PTR_ERR(child);
 
 			child = add_regulator_linked(TWL4030_REG_VUSB3V1,
-						      &usb_fixed, &usb3v1, 1,
+						      &usb_fixed, usb3v1, 2,
 						      features);
 			if (IS_ERR(child))
 				return PTR_ERR(child);
@@ -766,7 +767,7 @@ add_children(struct twl4030_platform_data *pdata, unsigned irq_base,
 		if (twl_has_regulator() && child) {
 			usb1v5.dev_name = dev_name(child);
 			usb1v8.dev_name = dev_name(child);
-			usb3v1.dev_name = dev_name(child);
+			usb3v1[0].dev_name = dev_name(child);
 		}
 	}
 	if (twl_has_usb() && pdata->usb && twl_class_is_6030()) {

drivers/power/twl4030_charger.c

@@ -21,6 +21,7 @@
 #include <linux/power_supply.h>
 #include <linux/notifier.h>
 #include <linux/usb/otg.h>
+#include <linux/regulator/machine.h>
 
 #define TWL4030_BCIMSTATEC	0x02
 #define TWL4030_BCIICHG		0x08
@@ -86,6 +87,8 @@ struct twl4030_bci {
 	struct work_struct	work;
 	int			irq_chg;
 	int			irq_bci;
+	struct regulator	*usb_reg;
+	int			usb_enabled;
 
 	unsigned long		event;
 };
@@ -183,6 +186,12 @@ static int twl4030_charger_enable_usb(struct twl4030_bci *bci, bool enable)
 			return -EACCES;
 		}
 
+		/* Need to keep regulator on */
+		if (!bci->usb_enabled) {
+			regulator_enable(bci->usb_reg);
+			bci->usb_enabled = 1;
+		}
+
 		/* forcing the field BCIAUTOUSB (BOOT_BCI[1]) to 1 */
 		ret = twl4030_clear_set_boot_bci(0, TWL4030_BCIAUTOUSB);
 		if (ret < 0)
@@ -193,6 +202,10 @@ static int twl4030_charger_enable_usb(struct twl4030_bci *bci, bool enable)
 			TWL4030_USBFASTMCHG, TWL4030_BCIMFSTS4);
 	} else {
 		ret = twl4030_clear_set_boot_bci(TWL4030_BCIAUTOUSB, 0);
+		if (bci->usb_enabled) {
+			regulator_disable(bci->usb_reg);
+			bci->usb_enabled = 0;
+		}
 	}
 
 	return ret;
@@ -511,6 +524,8 @@ static int __init twl4030_bci_probe(struct platform_device *pdev)
 	bci->usb.num_properties = ARRAY_SIZE(twl4030_charger_props);
 	bci->usb.get_property = twl4030_bci_get_property;
 
+	bci->usb_reg = regulator_get(bci->dev, "bci3v1");
+
 	ret = power_supply_register(&pdev->dev, &bci->usb);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to register usb: %d\n", ret);