regulator: tps80031: Controls regulator output by PREQ

Based on platform, it is require to control the regulator
output through the peripheral power request signal to pmu.
Supporting this type of platform configuration to control
output voltage by sw as well as through PREQ input line.

bug 839809
bug 829405

Original-Change-Id: Ifa19b9062ca2a2c5cae84de1f311a33cec094ad0
Reviewed-on: http://git-master/r/38936
Reviewed-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Bitan Biswas <bbiswas@nvidia.com>
Tested-by: Bitan Biswas <bbiswas@nvidia.com>

Rebase-Id: R396800524fcea5c74711aec305c29229d32a0908

3 files changed, 124 insertions, 20 deletions

diff --git a/drivers/mfd/tps80031.c b/drivers/mfd/tps80031.c
index 9167e1b5faec..4b80f65cc924 100644
--- a/drivers/mfd/tps80031.c
+++ b/drivers/mfd/tps80031.c
@@ -685,6 +685,8 @@ static int dbg_tps_show(struct seq_file *s, void *unused)
 	print_regs("CLK32KG Regs",   s, SLAVE_ID1, 0xBD, 0xBE);
 	print_regs("CLK32KAUD Regs", s, SLAVE_ID1, 0xC0, 0xC1);
 	print_regs("INT Regs",       s, SLAVE_ID2, 0xD0, 0xD8);
+	print_regs("PREQ Regs",      s, SLAVE_ID1, 0xD7, 0xDF);
+	print_regs("MASK_PH Regs",   s, SLAVE_ID1, 0x20, 0x21);
 	print_regs("VERNUM Regs",    s, SLAVE_ID1, 0x87, 0x87);
 	return 0;
 }
diff --git a/drivers/regulator/tps80031-regulator.c b/drivers/regulator/tps80031-regulator.c
index 86c8636ba40a..792e47c07496 100644
--- a/drivers/regulator/tps80031-regulator.c
+++ b/drivers/regulator/tps80031-regulator.c
@@ -65,6 +65,13 @@
 #define OPA_MODE_EN		BIT(6)
 #define OPA_MODE_EN_MASK	BIT(6)
 
+#define EXT_PWR_REQ (PWR_REQ_INPUT_PREQ1 | PWR_REQ_INPUT_PREQ2 | \
+			PWR_REQ_INPUT_PREQ3)
+#define TPS80031_PREQ1_RES_ASS_A	0xD7
+#define TPS80031_PREQ2_RES_ASS_A	0xDA
+#define TPS80031_PREQ3_RES_ASS_A	0xDD
+#define TPS80031_PHOENIX_MSK_TRANSITION	0x20
+
 struct tps80031_regulator {
 
 	/* Regulator register address.*/
@@ -92,6 +99,9 @@ struct tps80031_regulator {
 
 	/* Device */
 	struct device		*dev;
+
+	/*Power request bits */
+	int preq_bit;
 };
 
 static inline struct device *to_tps80031_dev(struct regulator_dev *rdev)
@@ -139,6 +149,9 @@ static int tps80031_reg_is_enabled(struct regulator_dev *rdev)
 	uint8_t state;
 	int ret;
 
+	if (ri->platform_flags & EXT_PWR_REQ)
+		return true;
+
 	ret = tps80031_read(parent, SLAVE_ID1, ri->state_reg, &state);
 	if (ret < 0) {
 		dev_err(&rdev->dev, "Error in reading the STATE register\n");
@@ -153,6 +166,9 @@ static int tps80031_reg_enable(struct regulator_dev *rdev)
 	struct device *parent = to_tps80031_dev(rdev);
 	int ret;
 
+	if (ri->platform_flags & EXT_PWR_REQ)
+		return 0;
+
 	ret = tps80031_update(parent, SLAVE_ID1, ri->state_reg, STATE_ON,
 					STATE_MASK);
 	if (ret < 0) {
@@ -169,6 +185,9 @@ static int tps80031_reg_disable(struct regulator_dev *rdev)
 	struct device *parent = to_tps80031_dev(rdev);
 	int ret;
 
+	if (ri->platform_flags & EXT_PWR_REQ)
+		return 0;
+
 	ret = tps80031_update(parent, SLAVE_ID1, ri->state_reg, STATE_OFF,
 					STATE_MASK);
 	if (ret < 0)
@@ -637,7 +656,8 @@ static struct regulator_ops tps80031vbus_ops = {
 };
 
 #define TPS80031_REG(_id, _trans_reg, _state_reg, _force_reg, _volt_reg, \
-		_volt_id, min_mVolts, max_mVolts, _ops, _n_volt, _delay) \
+		_volt_id, min_mVolts, max_mVolts, _ops, _n_volt, _delay, \
+		_preq_bit)						 \
 {								\
 	.trans_reg = _trans_reg,				\
 	.state_reg = _state_reg,				\
@@ -656,29 +676,101 @@ static struct regulator_ops tps80031vbus_ops = {
 		.owner = THIS_MODULE,				\
 	},							\
 	.delay = _delay,					\
+	.preq_bit = _preq_bit,					\
 }
 
 static struct tps80031_regulator tps80031_regulator[] = {
-	TPS80031_REG(VIO,   0x47, 0x48, 0x49, 0x4A, SLAVE_ID0, 600, 2100, tps80031dcdc_ops, 63, 500),
-	TPS80031_REG(SMPS1, 0x53, 0x54, 0x55, 0x56, SLAVE_ID0, 600, 2100, tps80031dcdc_ops, 63, 500),
-	TPS80031_REG(SMPS2, 0x59, 0x5A, 0x5B, 0x5C, SLAVE_ID0, 600, 2100, tps80031dcdc_ops, 63, 500),
-	TPS80031_REG(SMPS3, 0x65, 0x66, 0x00, 0x68, SLAVE_ID1, 600, 2100, tps80031dcdc_ops, 63, 500),
-	TPS80031_REG(SMPS4, 0x41, 0x42, 0x00, 0x44, SLAVE_ID1, 600, 2100, tps80031dcdc_ops, 63, 500),
-
-	TPS80031_REG(LDO1,   0x9D, 0x9E, 0x00, 0x9F, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(LDO2,   0x85, 0x86, 0x00, 0x87, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(LDO3,   0x8D, 0x8E, 0x00, 0x8F, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(LDO4,   0x89, 0x8A, 0x00, 0x8B, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(LDO5,   0x99, 0x9A, 0x00, 0x9B, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(LDO6,   0x91, 0x92, 0x00, 0x93, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(LDO7,   0xA5, 0xA6, 0x00, 0xA7, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(LDOUSB, 0xA1, 0xA2, 0x00, 0xA3, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(LDOLN,  0x95, 0x96, 0x00, 0x97, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(VANA,   0x81, 0x82, 0x00, 0x83, SLAVE_ID1, 1100, 3300, tps80031ldo_ops, 24, 500),
-	TPS80031_REG(VBUS,   0x0,  0x0,  0x00, 0x0,  SLAVE_ID1, 0,    5000, tps80031vbus_ops, 2, 500),
+	TPS80031_REG(VIO,   0x47, 0x48, 0x49, 0x4A, SLAVE_ID0, 600, 2100,
+				tps80031dcdc_ops, 63, 500, 4),
+	TPS80031_REG(SMPS1, 0x53, 0x54, 0x55, 0x56, SLAVE_ID0, 600, 2100,
+				tps80031dcdc_ops, 63, 500, 0),
+	TPS80031_REG(SMPS2, 0x59, 0x5A, 0x5B, 0x5C, SLAVE_ID0, 600, 2100,
+				tps80031dcdc_ops, 63, 500, 1),
+	TPS80031_REG(SMPS3, 0x65, 0x66, 0x00, 0x68, SLAVE_ID1, 600, 2100,
+				tps80031dcdc_ops, 63, 500, 2),
+	TPS80031_REG(SMPS4, 0x41, 0x42, 0x00, 0x44, SLAVE_ID1, 600, 2100,
+				tps80031dcdc_ops, 63, 500, 3),
+
+	TPS80031_REG(LDO1,   0x9D, 0x9E, 0x00, 0x9F, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, 8),
+	TPS80031_REG(LDO2,   0x85, 0x86, 0x00, 0x87, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, 9),
+	TPS80031_REG(LDO3,   0x8D, 0x8E, 0x00, 0x8F, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, 10),
+	TPS80031_REG(LDO4,   0x89, 0x8A, 0x00, 0x8B, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, 11),
+	TPS80031_REG(LDO5,   0x99, 0x9A, 0x00, 0x9B, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, 12),
+	TPS80031_REG(LDO6,   0x91, 0x92, 0x00, 0x93, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, 13),
+	TPS80031_REG(LDO7,   0xA5, 0xA6, 0x00, 0xA7, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, 14),
+	TPS80031_REG(LDOUSB, 0xA1, 0xA2, 0x00, 0xA3, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, 5),
+	TPS80031_REG(LDOLN,  0x95, 0x96, 0x00, 0x97, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, 15),
+	TPS80031_REG(VANA,   0x81, 0x82, 0x00, 0x83, SLAVE_ID1, 1100, 3300,
+				tps80031ldo_ops, 24, 500, -1),
+	TPS80031_REG(VBUS,   0x0,  0x0,  0x00, 0x0,  SLAVE_ID1, 0,    5000,
+				tps80031vbus_ops, 2, 500, -1),
 };
 
-static inline int tps80031_regulator_preinit(struct device *parent,
+static int tps80031_power_req_config(struct device *parent,
+		struct tps80031_regulator *ri,
+		struct tps80031_regulator_platform_data *tps80031_pdata)
+{
+	u8 res_ass_reg;
+	int preq_bit;
+	int preq_mask_bit;
+	int ret;
+
+	if (!(ri->platform_flags & EXT_PWR_REQ))
+		return 0;
+
+	preq_bit = ri->preq_bit & 0x7;
+	if (ri->platform_flags & PWR_REQ_INPUT_PREQ1) {
+		res_ass_reg = TPS80031_PREQ1_RES_ASS_A + (ri->preq_bit >> 3);
+		preq_mask_bit = 5;
+	} else if (ri->platform_flags & PWR_REQ_INPUT_PREQ2) {
+		res_ass_reg = TPS80031_PREQ2_RES_ASS_A + (ri->preq_bit >> 3);
+		preq_mask_bit = 6;
+	} else if (ri->platform_flags & PWR_REQ_INPUT_PREQ3) {
+		res_ass_reg = TPS80031_PREQ3_RES_ASS_A + (ri->preq_bit >> 3);
+		preq_mask_bit = 7;
+	}
+
+	/* Configure REQ_ASS registers */
+	ret = tps80031_set_bits(parent, SLAVE_ID1, res_ass_reg, BIT(preq_bit));
+	if (ret < 0) {
+		dev_err(ri->dev, "%s() Not able to set bit %d of "
+			"reg %d error %d\n",
+			__func__, preq_bit, res_ass_reg, ret);
+		return ret;
+	}
+
+	/* Unmask the PREQ */
+	ret = tps80031_clr_bits(parent, SLAVE_ID1,
+			TPS80031_PHOENIX_MSK_TRANSITION, BIT(preq_mask_bit));
+	if (ret < 0) {
+		dev_err(ri->dev, "%s() Not able to clear bit %d of "
+			"reg %d error %d\n",
+			 __func__, preq_mask_bit,
+			TPS80031_PHOENIX_MSK_TRANSITION, ret);
+		return ret;
+	}
+
+	/* Switch regulator control to resource now */
+	ret = tps80031_update(parent, SLAVE_ID1, ri->state_reg, 0x0,
+					STATE_MASK);
+	if (ret < 0) {
+		dev_err(ri->dev, "%s() Error in updating the STATE "
+				"register error %d\n", __func__, ret);
+		return ret;
+	}
+	return ret;
+}
+
+static int tps80031_regulator_preinit(struct device *parent,
 		struct tps80031_regulator *ri,
 		struct tps80031_regulator_platform_data *tps80031_pdata)
 {
@@ -704,7 +796,8 @@ static inline int tps80031_regulator_preinit(struct device *parent,
 		if (ri->platform_flags & LDO3_OUTPUT_VIB)
 			ret = tps80031_update(parent, SLAVE_ID1,
 				TPS80031_MISC2_ADD,
-				MISC2_LDO3_SEL_VIB_VAL,MISC2_LDO3_SEL_VIB_MASK);
+				MISC2_LDO3_SEL_VIB_VAL,
+				MISC2_LDO3_SEL_VIB_MASK);
 		if (ret < 0) {
 			dev_err(ri->dev, "Not able to configure the rail "
 				"LDO3 as per platform data error %d\n", ret);
@@ -835,6 +928,10 @@ static int __devinit tps80031_regulator_probe(struct platform_device *pdev)
 	if (err)
 		return err;
 
+	err = tps80031_power_req_config(pdev->dev.parent, ri, tps_pdata);
+	if (err)
+		return err;
+
 	rdev = regulator_register(&ri->desc, &pdev->dev,
 				&tps_pdata->regulator, ri);
 	if (IS_ERR_OR_NULL(rdev)) {
diff --git a/include/linux/regulator/tps80031-regulator.h b/include/linux/regulator/tps80031-regulator.h
index 86bbadba8df5..92787df097ce 100644
--- a/include/linux/regulator/tps80031-regulator.h
+++ b/include/linux/regulator/tps80031-regulator.h
@@ -37,6 +37,11 @@ enum {
 	/* VBUS configuration */
 	VBUS_SW_ONLY		= 0x00000008,
 	VBUS_SW_N_ID		= 0x00000010,
+
+	/* Power requests */
+	PWR_REQ_INPUT_PREQ1	= 0x00000020,
+	PWR_REQ_INPUT_PREQ2	= 0x00000040,
+	PWR_REQ_INPUT_PREQ3	= 0x00000080,
 };
 
 /*