power: supply: bq25890_charger: Add support of BQ25892 and BQ25896 chips

Support BQ25892 and BQ25896 chips by this driver. They shared one chip
ID 0, so distinquish them by device revisions (2 for 25896 and 1 for
25892).
Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/power/supply/bq25890_charger.c

@@ -25,12 +25,20 @@
 #define BQ25895_ID			7
 #define BQ25896_ID			0
 
+enum bq25890_chip_version {
+	BQ25890,
+	BQ25892,
+	BQ25895,
+	BQ25896,
+};
+
 enum bq25890_fields {
 	F_EN_HIZ, F_EN_ILIM, F_IILIM,				     /* Reg00 */
 	F_BHOT, F_BCOLD, F_VINDPM_OFS,				     /* Reg01 */
 	F_CONV_START, F_CONV_RATE, F_BOOSTF, F_ICO_EN,
 	F_HVDCP_EN, F_MAXC_EN, F_FORCE_DPM, F_AUTO_DPDM_EN,	     /* Reg02 */
-	F_BAT_LOAD_EN, F_WD_RST, F_OTG_CFG, F_CHG_CFG, F_SYSVMIN,    /* Reg03 */
+	F_BAT_LOAD_EN, F_WD_RST, F_OTG_CFG, F_CHG_CFG, F_SYSVMIN,
+	F_MIN_VBAT_SEL,						     /* Reg03 */
 	F_PUMPX_EN, F_ICHG,					     /* Reg04 */
 	F_IPRECHG, F_ITERM,					     /* Reg05 */
 	F_VREG, F_BATLOWV, F_VRECHG,				     /* Reg06 */
@@ -39,8 +47,9 @@ enum bq25890_fields {
 	F_BATCMP, F_VCLAMP, F_TREG,				     /* Reg08 */
 	F_FORCE_ICO, F_TMR2X_EN, F_BATFET_DIS, F_JEITA_VSET,
 	F_BATFET_DLY, F_BATFET_RST_EN, F_PUMPX_UP, F_PUMPX_DN,	     /* Reg09 */
-	F_BOOSTV, F_BOOSTI,					     /* Reg0A */
-	F_VBUS_STAT, F_CHG_STAT, F_PG_STAT, F_SDP_STAT, F_VSYS_STAT, /* Reg0B */
+	F_BOOSTV, F_PFM_OTG_DIS, F_BOOSTI,			     /* Reg0A */
+	F_VBUS_STAT, F_CHG_STAT, F_PG_STAT, F_SDP_STAT, F_0B_RSVD,
+	F_VSYS_STAT,						     /* Reg0B */
 	F_WD_FAULT, F_BOOST_FAULT, F_CHG_FAULT, F_BAT_FAULT,
 	F_NTC_FAULT,						     /* Reg0C */
 	F_FORCE_VINDPM, F_VINDPM,				     /* Reg0D */
@@ -91,7 +100,7 @@ struct bq25890_device {
 	struct regmap *rmap;
 	struct regmap_field *rmap_fields[F_MAX_FIELDS];
 
-	int chip_id;
+	enum bq25890_chip_version chip_version;
 	struct bq25890_init_data init_data;
 	struct bq25890_state state;
 
@@ -111,8 +120,7 @@ static const struct regmap_access_table bq25890_writeable_regs = {
 static const struct regmap_range bq25890_volatile_reg_ranges[] = {
 	regmap_reg_range(0x00, 0x00),
 	regmap_reg_range(0x09, 0x09),
-	regmap_reg_range(0x0b, 0x0c),
-	regmap_reg_range(0x0e, 0x14),
+	regmap_reg_range(0x0b, 0x14),
 };
 
 static const struct regmap_access_table bq25890_volatile_regs = {
@@ -155,7 +163,7 @@ static const struct reg_field bq25890_reg_fields[] = {
 	[F_OTG_CFG]		= REG_FIELD(0x03, 5, 5),
 	[F_CHG_CFG]		= REG_FIELD(0x03, 4, 4),
 	[F_SYSVMIN]		= REG_FIELD(0x03, 1, 3),
-	/* MIN_VBAT_SEL on BQ25896 */
+	[F_MIN_VBAT_SEL]	= REG_FIELD(0x03, 0, 0), // BQ25896 only
 	/* REG04 */
 	[F_PUMPX_EN]		= REG_FIELD(0x04, 7, 7),
 	[F_ICHG]		= REG_FIELD(0x04, 0, 6),
@@ -188,8 +196,8 @@ static const struct reg_field bq25890_reg_fields[] = {
 	[F_PUMPX_DN]		= REG_FIELD(0x09, 0, 0),
 	/* REG0A */
 	[F_BOOSTV]		= REG_FIELD(0x0A, 4, 7),
-	/* PFM_OTG_DIS 3 on BQ25896 */
 	[F_BOOSTI]		= REG_FIELD(0x0A, 0, 2), // reserved on BQ25895
+	[F_PFM_OTG_DIS]		= REG_FIELD(0x0A, 3, 3), // BQ25896 only
 	/* REG0B */
 	[F_VBUS_STAT]		= REG_FIELD(0x0B, 5, 7),
 	[F_CHG_STAT]		= REG_FIELD(0x0B, 3, 4),
@@ -275,6 +283,7 @@ static const union {
 	struct bq25890_lookup lt;
 } bq25890_tables[] = {
 	/* range tables */
+	/* TODO: BQ25896 has max ICHG 3008 mA */
 	[TBL_ICHG] =	{ .rt = {0,	  5056000, 64000} },	 /* uA */
 	[TBL_ITERM] =	{ .rt = {64000,   1024000, 64000} },	 /* uA */
 	[TBL_VREG] =	{ .rt = {3840000, 4608000, 16000} },	 /* uV */
@@ -391,11 +400,13 @@ static int bq25890_power_supply_get_property(struct power_supply *psy,
 		break;
 
 	case POWER_SUPPLY_PROP_MODEL_NAME:
-		if (bq->chip_id == BQ25890_ID)
+		if (bq->chip_version == BQ25890)
 			val->strval = "BQ25890";
-		else if (bq->chip_id == BQ25895_ID)
+		else if (bq->chip_version == BQ25892)
+			val->strval = "BQ25892";
+		else if (bq->chip_version == BQ25895)
 			val->strval = "BQ25895";
-		else if (bq->chip_id == BQ25896_ID)
+		else if (bq->chip_version == BQ25896)
 			val->strval = "BQ25896";
 		else
 			val->strval = "UNKNOWN";
@@ -741,6 +752,56 @@ static int bq25890_usb_notifier(struct notifier_block *nb, unsigned long val,
 	return NOTIFY_OK;
 }
 
+static int bq25890_get_chip_version(struct bq25890_device *bq)
+{
+	int id, rev;
+
+	id = bq25890_field_read(bq, F_PN);
+	if (id < 0) {
+		dev_err(bq->dev, "Cannot read chip ID.\n");
+		return id;
+	}
+
+	rev = bq25890_field_read(bq, F_DEV_REV);
+	if (rev < 0) {
+		dev_err(bq->dev, "Cannot read chip revision.\n");
+		return id;
+	}
+
+	switch (id) {
+	case BQ25890_ID:
+		bq->chip_version = BQ25890;
+		break;
+
+	/* BQ25892 and BQ25896 share same ID 0 */
+	case BQ25896_ID:
+		switch (rev) {
+		case 2:
+			bq->chip_version = BQ25896;
+			break;
+		case 1:
+			bq->chip_version = BQ25892;
+			break;
+		default:
+			dev_err(bq->dev,
+				"Unknown device revision %d, assume BQ25892\n",
+				rev);
+			bq->chip_version = BQ25892;
+		}
+		break;
+
+	case BQ25895_ID:
+		bq->chip_version = BQ25895;
+		break;
+
+	default:
+		dev_err(bq->dev, "Unknown chip ID %d\n", id);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
 static int bq25890_irq_probe(struct bq25890_device *bq)
 {
 	struct gpio_desc *irq;
@@ -859,16 +920,10 @@ static int bq25890_probe(struct i2c_client *client,
 
 	i2c_set_clientdata(client, bq);
 
-	bq->chip_id = bq25890_field_read(bq, F_PN);
-	if (bq->chip_id < 0) {
-		dev_err(dev, "Cannot read chip ID.\n");
-		return bq->chip_id;
-	}
-
-	if ((bq->chip_id != BQ25890_ID) && (bq->chip_id != BQ25895_ID)
-			&& (bq->chip_id != BQ25896_ID)) {
-		dev_err(dev, "Chip with ID=%d, not supported!\n", bq->chip_id);
-		return -ENODEV;
+	ret = bq25890_get_chip_version(bq);
+	if (ret) {
+		dev_err(dev, "Cannot read chip ID or unknown chip.\n");
+		return ret;
 	}
 
 	if (!dev->platform_data) {