Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 339 insertions, 0 deletions

diff --git a/drivers/regulator/max8952.c b/drivers/regulator/max8952.c
new file mode 100644
index 0000000000..0b0b841d21
--- /dev/null
+++ b/drivers/regulator/max8952.c
@@ -0,0 +1,339 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * max8952.c - Voltage and current regulation for the Maxim 8952
+ *
+ * Copyright (C) 2010 Samsung Electronics
+ * MyungJoo Ham <myungjoo.ham@samsung.com>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/max8952.h>
+#include <linux/gpio/consumer.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/slab.h>
+
+/* Registers */
+enum {
+	MAX8952_REG_MODE0,
+	MAX8952_REG_MODE1,
+	MAX8952_REG_MODE2,
+	MAX8952_REG_MODE3,
+	MAX8952_REG_CONTROL,
+	MAX8952_REG_SYNC,
+	MAX8952_REG_RAMP,
+	MAX8952_REG_CHIP_ID1,
+	MAX8952_REG_CHIP_ID2,
+};
+
+struct max8952_data {
+	struct i2c_client	*client;
+	struct max8952_platform_data *pdata;
+	struct gpio_desc *vid0_gpiod;
+	struct gpio_desc *vid1_gpiod;
+	bool vid0;
+	bool vid1;
+};
+
+static int max8952_read_reg(struct max8952_data *max8952, u8 reg)
+{
+	int ret = i2c_smbus_read_byte_data(max8952->client, reg);
+
+	if (ret > 0)
+		ret &= 0xff;
+
+	return ret;
+}
+
+static int max8952_write_reg(struct max8952_data *max8952,
+		u8 reg, u8 value)
+{
+	return i2c_smbus_write_byte_data(max8952->client, reg, value);
+}
+
+static int max8952_list_voltage(struct regulator_dev *rdev,
+		unsigned int selector)
+{
+	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
+
+	if (rdev_get_id(rdev) != 0)
+		return -EINVAL;
+
+	return (max8952->pdata->dvs_mode[selector] * 10 + 770) * 1000;
+}
+
+static int max8952_get_voltage_sel(struct regulator_dev *rdev)
+{
+	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
+	u8 vid = 0;
+
+	if (max8952->vid0)
+		vid += 1;
+	if (max8952->vid1)
+		vid += 2;
+
+	return vid;
+}
+
+static int max8952_set_voltage_sel(struct regulator_dev *rdev,
+				   unsigned selector)
+{
+	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
+
+	if (!max8952->vid0_gpiod || !max8952->vid1_gpiod) {
+		/* DVS not supported */
+		return -EPERM;
+	}
+
+	max8952->vid0 = selector & 0x1;
+	max8952->vid1 = (selector >> 1) & 0x1;
+	gpiod_set_value(max8952->vid0_gpiod, max8952->vid0);
+	gpiod_set_value(max8952->vid1_gpiod, max8952->vid1);
+
+	return 0;
+}
+
+static const struct regulator_ops max8952_ops = {
+	.list_voltage		= max8952_list_voltage,
+	.get_voltage_sel	= max8952_get_voltage_sel,
+	.set_voltage_sel	= max8952_set_voltage_sel,
+};
+
+static const struct regulator_desc regulator = {
+	.name		= "MAX8952_VOUT",
+	.id		= 0,
+	.n_voltages	= MAX8952_NUM_DVS_MODE,
+	.ops		= &max8952_ops,
+	.type		= REGULATOR_VOLTAGE,
+	.owner		= THIS_MODULE,
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id max8952_dt_match[] = {
+	{ .compatible = "maxim,max8952" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, max8952_dt_match);
+
+static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
+{
+	struct max8952_platform_data *pd;
+	struct device_node *np = dev->of_node;
+	int ret;
+	int i;
+
+	pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
+	if (!pd)
+		return NULL;
+
+	if (of_property_read_u32(np, "max8952,default-mode", &pd->default_mode))
+		dev_warn(dev, "Default mode not specified, assuming 0\n");
+
+	ret = of_property_read_u32_array(np, "max8952,dvs-mode-microvolt",
+					pd->dvs_mode, ARRAY_SIZE(pd->dvs_mode));
+	if (ret) {
+		dev_err(dev, "max8952,dvs-mode-microvolt property not specified");
+		return NULL;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(pd->dvs_mode); ++i) {
+		if (pd->dvs_mode[i] < 770000 || pd->dvs_mode[i] > 1400000) {
+			dev_err(dev, "DVS voltage %d out of range\n", i);
+			return NULL;
+		}
+		pd->dvs_mode[i] = (pd->dvs_mode[i] - 770000) / 10000;
+	}
+
+	if (of_property_read_u32(np, "max8952,sync-freq", &pd->sync_freq))
+		dev_warn(dev, "max8952,sync-freq property not specified, defaulting to 26MHz\n");
+
+	if (of_property_read_u32(np, "max8952,ramp-speed", &pd->ramp_speed))
+		dev_warn(dev, "max8952,ramp-speed property not specified, defaulting to 32mV/us\n");
+
+	pd->reg_data = of_get_regulator_init_data(dev, np, &regulator);
+	if (!pd->reg_data) {
+		dev_err(dev, "Failed to parse regulator init data\n");
+		return NULL;
+	}
+
+	return pd;
+}
+#else
+static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
+{
+	return NULL;
+}
+#endif
+
+static int max8952_pmic_probe(struct i2c_client *client)
+{
+	struct i2c_adapter *adapter = client->adapter;
+	struct max8952_platform_data *pdata = dev_get_platdata(&client->dev);
+	struct regulator_config config = { };
+	struct max8952_data *max8952;
+	struct regulator_dev *rdev;
+	struct gpio_desc *gpiod;
+	enum gpiod_flags gflags;
+
+	int ret = 0;
+
+	if (client->dev.of_node)
+		pdata = max8952_parse_dt(&client->dev);
+
+	if (!pdata) {
+		dev_err(&client->dev, "Require the platform data\n");
+		return -EINVAL;
+	}
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
+		return -EIO;
+
+	max8952 = devm_kzalloc(&client->dev, sizeof(struct max8952_data),
+			       GFP_KERNEL);
+	if (!max8952)
+		return -ENOMEM;
+
+	max8952->client = client;
+	max8952->pdata = pdata;
+
+	config.dev = &client->dev;
+	config.init_data = pdata->reg_data;
+	config.driver_data = max8952;
+	config.of_node = client->dev.of_node;
+
+	if (pdata->reg_data->constraints.boot_on)
+		gflags = GPIOD_OUT_HIGH;
+	else
+		gflags = GPIOD_OUT_LOW;
+	gflags |= GPIOD_FLAGS_BIT_NONEXCLUSIVE;
+	/*
+	 * Do not use devm* here: the regulator core takes over the
+	 * lifecycle management of the GPIO descriptor.
+	 */
+	gpiod = gpiod_get_optional(&client->dev,
+				   "max8952,en",
+				   gflags);
+	if (IS_ERR(gpiod))
+		return PTR_ERR(gpiod);
+	if (gpiod)
+		config.ena_gpiod = gpiod;
+
+	rdev = devm_regulator_register(&client->dev, &regulator, &config);
+	if (IS_ERR(rdev)) {
+		ret = PTR_ERR(rdev);
+		dev_err(&client->dev, "regulator init failed (%d)\n", ret);
+		return ret;
+	}
+
+	max8952->vid0 = pdata->default_mode & 0x1;
+	max8952->vid1 = (pdata->default_mode >> 1) & 0x1;
+
+	/* Fetch vid0 and vid1 GPIOs if available */
+	gflags = max8952->vid0 ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
+	max8952->vid0_gpiod = devm_gpiod_get_index_optional(&client->dev,
+							    "max8952,vid",
+							    0, gflags);
+	if (IS_ERR(max8952->vid0_gpiod))
+		return PTR_ERR(max8952->vid0_gpiod);
+	gflags = max8952->vid1 ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
+	max8952->vid1_gpiod = devm_gpiod_get_index_optional(&client->dev,
+							    "max8952,vid",
+							    1, gflags);
+	if (IS_ERR(max8952->vid1_gpiod))
+		return PTR_ERR(max8952->vid1_gpiod);
+
+	/* If either VID GPIO is missing just disable this */
+	if (!max8952->vid0_gpiod || !max8952->vid1_gpiod) {
+		dev_warn(&client->dev, "VID0/1 gpio invalid: "
+			 "DVS not available.\n");
+		max8952->vid0 = 0;
+		max8952->vid1 = 0;
+		/* Make sure if we have any descriptors they get set to low */
+		if (max8952->vid0_gpiod)
+			gpiod_set_value(max8952->vid0_gpiod, 0);
+		if (max8952->vid1_gpiod)
+			gpiod_set_value(max8952->vid1_gpiod, 0);
+
+		/* Disable Pulldown of EN only */
+		max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x60);
+
+		dev_err(&client->dev, "DVS modes disabled because VID0 and VID1"
+				" do not have proper controls.\n");
+	} else {
+		/*
+		 * Disable Pulldown on EN, VID0, VID1 to reduce
+		 * leakage current of MAX8952 assuming that MAX8952
+		 * is turned on (EN==1). Note that without having VID0/1
+		 * properly connected, turning pulldown off can be
+		 * problematic. Thus, turn this off only when they are
+		 * controllable by GPIO.
+		 */
+		max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x0);
+	}
+
+	max8952_write_reg(max8952, MAX8952_REG_MODE0,
+			(max8952_read_reg(max8952,
+					  MAX8952_REG_MODE0) & 0xC0) |
+			(pdata->dvs_mode[0] & 0x3F));
+	max8952_write_reg(max8952, MAX8952_REG_MODE1,
+			(max8952_read_reg(max8952,
+					  MAX8952_REG_MODE1) & 0xC0) |
+			(pdata->dvs_mode[1] & 0x3F));
+	max8952_write_reg(max8952, MAX8952_REG_MODE2,
+			(max8952_read_reg(max8952,
+					  MAX8952_REG_MODE2) & 0xC0) |
+			(pdata->dvs_mode[2] & 0x3F));
+	max8952_write_reg(max8952, MAX8952_REG_MODE3,
+			(max8952_read_reg(max8952,
+					  MAX8952_REG_MODE3) & 0xC0) |
+			(pdata->dvs_mode[3] & 0x3F));
+
+	max8952_write_reg(max8952, MAX8952_REG_SYNC,
+			(max8952_read_reg(max8952, MAX8952_REG_SYNC) & 0x3F) |
+			((pdata->sync_freq & 0x3) << 6));
+	max8952_write_reg(max8952, MAX8952_REG_RAMP,
+			(max8952_read_reg(max8952, MAX8952_REG_RAMP) & 0x1F) |
+			((pdata->ramp_speed & 0x7) << 5));
+
+	i2c_set_clientdata(client, max8952);
+
+	return 0;
+}
+
+static const struct i2c_device_id max8952_ids[] = {
+	{ "max8952", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, max8952_ids);
+
+static struct i2c_driver max8952_pmic_driver = {
+	.probe		= max8952_pmic_probe,
+	.driver		= {
+		.name	= "max8952",
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+		.of_match_table = of_match_ptr(max8952_dt_match),
+	},
+	.id_table	= max8952_ids,
+};
+
+static int __init max8952_pmic_init(void)
+{
+	return i2c_add_driver(&max8952_pmic_driver);
+}
+subsys_initcall(max8952_pmic_init);
+
+static void __exit max8952_pmic_exit(void)
+{
+	i2c_del_driver(&max8952_pmic_driver);
+}
+module_exit(max8952_pmic_exit);
+
+MODULE_DESCRIPTION("MAXIM 8952 voltage regulator driver");
+MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
+MODULE_LICENSE("GPL");