regulator: Add TPS65090 regulator driver

Add TPS65090 regulator driver

TPS65090 PMIC from TI consists of 3 step down converters,
2 always on LDOs and 7 current limited load switches. The
output voltages are ON/OFF controllable and are meant to
supply power to the components on target board.

Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/regulator/tps65090-regulator.c b/drivers/regulator/tps65090-regulator.c
new file mode 100644
index 0000000..6c28e3a
--- /dev/null
+++ b/drivers/regulator/tps65090-regulator.c
@@ -0,0 +1,197 @@
+/*
+ * Regulator driver for tps65090 power management chip.
+ *
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/mfd/tps65090.h>
+#include <linux/regulator/tps65090-regulator.h>
+
+struct tps65090_regulator {
+	int		id;
+	/* Regulator register address.*/
+	u8		reg_en_reg;
+	u8		en_bit;
+
+	/* used by regulator core */
+	struct regulator_desc	desc;
+
+	/* Device */
+	struct device		*dev;
+};
+
+static inline struct device *to_tps65090_dev(struct regulator_dev *rdev)
+{
+	return rdev_get_dev(rdev)->parent->parent;
+}
+
+static int tps65090_reg_is_enabled(struct regulator_dev *rdev)
+{
+	struct tps65090_regulator *ri = rdev_get_drvdata(rdev);
+	struct device *parent = to_tps65090_dev(rdev);
+	uint8_t control;
+	int ret;
+
+	ret = tps65090_read(parent, ri->reg_en_reg, &control);
+	if (ret < 0) {
+		dev_err(&rdev->dev, "Error in reading reg 0x%x\n",
+			ri->reg_en_reg);
+		return ret;
+	}
+	return (((control >> ri->en_bit) & 1) == 1);
+}
+
+static int tps65090_reg_enable(struct regulator_dev *rdev)
+{
+	struct tps65090_regulator *ri = rdev_get_drvdata(rdev);
+	struct device *parent = to_tps65090_dev(rdev);
+	int ret;
+
+	ret = tps65090_set_bits(parent, ri->reg_en_reg, ri->en_bit);
+	if (ret < 0)
+		dev_err(&rdev->dev, "Error in updating reg 0x%x\n",
+			ri->reg_en_reg);
+	return ret;
+}
+
+static int tps65090_reg_disable(struct regulator_dev *rdev)
+{
+	struct tps65090_regulator *ri = rdev_get_drvdata(rdev);
+	struct device *parent = to_tps65090_dev(rdev);
+	int ret;
+
+	ret = tps65090_clr_bits(parent, ri->reg_en_reg, ri->en_bit);
+	if (ret < 0)
+		dev_err(&rdev->dev, "Error in updating reg 0x%x\n",
+			ri->reg_en_reg);
+
+	return ret;
+}
+
+static struct regulator_ops tps65090_ops = {
+	.enable		= tps65090_reg_enable,
+	.disable	= tps65090_reg_disable,
+	.is_enabled	= tps65090_reg_is_enabled,
+};
+
+#define tps65090_REG(_id, _en_reg, _en_bit, _ops)	\
+{							\
+	.reg_en_reg	= _en_reg,			\
+	.en_bit		= _en_bit,			\
+	.id		= TPS65090_ID_##_id,		\
+	.desc = {					\
+		.name = tps65090_rails(_id),		\
+		.id = TPS65090_ID_##_id,		\
+		.ops = &_ops,				\
+		.type = REGULATOR_VOLTAGE,		\
+		.owner = THIS_MODULE,			\
+	},						\
+}
+
+static struct tps65090_regulator TPS65090_regulator[] = {
+	tps65090_REG(DCDC1, 12, 0, tps65090_ops),
+	tps65090_REG(DCDC2, 13, 0, tps65090_ops),
+	tps65090_REG(DCDC3, 14, 0, tps65090_ops),
+	tps65090_REG(FET1,  15, 0, tps65090_ops),
+	tps65090_REG(FET2,  16, 0, tps65090_ops),
+	tps65090_REG(FET3,  17, 0, tps65090_ops),
+	tps65090_REG(FET4,  18, 0, tps65090_ops),
+	tps65090_REG(FET5,  19, 0, tps65090_ops),
+	tps65090_REG(FET6,  20, 0, tps65090_ops),
+	tps65090_REG(FET7,  21, 0, tps65090_ops),
+};
+
+static inline struct tps65090_regulator *find_regulator_info(int id)
+{
+	struct tps65090_regulator *ri;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(TPS65090_regulator); i++) {
+		ri = &TPS65090_regulator[i];
+		if (ri->desc.id == id)
+			return ri;
+	}
+	return NULL;
+}
+
+static int __devinit tps65090_regulator_probe(struct platform_device *pdev)
+{
+	struct tps65090_regulator *ri = NULL;
+	struct regulator_dev *rdev;
+	struct tps65090_regulator_platform_data *tps_pdata;
+	int id = pdev->id;
+
+	dev_dbg(&pdev->dev, "Probing regulator %d\n", id);
+
+	ri = find_regulator_info(id);
+	if (ri == NULL) {
+		dev_err(&pdev->dev, "invalid regulator ID specified\n");
+		return -EINVAL;
+	}
+	tps_pdata = pdev->dev.platform_data;
+	ri->dev = &pdev->dev;
+
+	rdev = regulator_register(&ri->desc, &pdev->dev,
+				&tps_pdata->regulator, ri, NULL);
+	if (IS_ERR_OR_NULL(rdev)) {
+		dev_err(&pdev->dev, "failed to register regulator %s\n",
+				ri->desc.name);
+		return PTR_ERR(rdev);
+	}
+
+	platform_set_drvdata(pdev, rdev);
+	return 0;
+}
+
+static int __devexit tps65090_regulator_remove(struct platform_device *pdev)
+{
+	struct regulator_dev *rdev = platform_get_drvdata(pdev);
+
+	regulator_unregister(rdev);
+	return 0;
+}
+
+static struct platform_driver tps65090_regulator_driver = {
+	.driver	= {
+		.name	= "tps65090-regulator",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= tps65090_regulator_probe,
+	.remove		= __devexit_p(tps65090_regulator_remove),
+};
+
+static int __init tps65090_regulator_init(void)
+{
+	return platform_driver_register(&tps65090_regulator_driver);
+}
+subsys_initcall(tps65090_regulator_init);
+
+static void __exit tps65090_regulator_exit(void)
+{
+	platform_driver_unregister(&tps65090_regulator_driver);
+}
+module_exit(tps65090_regulator_exit);
+
+MODULE_DESCRIPTION("tps65090 regulator driver");
+MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>");
+MODULE_LICENSE("GPL v2");