[PATCH 2/2] regulator: Add MAX20086-MAX20089 driver
From: Laurent Pinchart
Date: Sun Jan 02 2022 - 16:11:45 EST
From: Watson Chow <watson.chow@xxxxxxxxx>
The MAX20086-MAX20089 are dual/quad power protectors for cameras. Add a
driver that supports controlling the outputs individually. Additional
features, such as overcurrent detection, may be added later if needed.
Signed-off-by: Watson Chow <watson.chow@xxxxxxxxx>
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
Changes since v0:
- Remove unused regulator_config members
- Drop unused header
- Use SPDX header
- Sort headers alphabetically
- Fix macros indendation
- Removed unused macros
- Remove debugging printks
- Drop IRQ support
- Fix indentation and formatting
- Drop unsupported operations
- Allocate of_regulator_match on the stack
- Make regulator desc macro parameterized
- Reinit regulator_config for each regulator
- Disable interrupts before registering regulators
- Drop error variable in probe()
- Use sizeof(variable) instead of sizeof(type)
- Register regulators last
- Move configuration out of detection
- Move detection to separate function
- Move gpiod_get() to probe()
- Reorganize struct max20087
- Specify device ID in match data
- Specify number of outputs in info structure
- Drop min/max voltages
- Reorder functions
- Don't read CONFIG at probe time
- Fail probe() if disabling outputs fails
- Clean up messages
- Use .probe_new()
- Include vendor prefix in compatible string
- Support MAX20086, 88 and 89
- Reorder Kconfig and Makefile entries
- Reorganize regulator data
- Drop unneeded headers
- Fail if no output is found in DT
- Set enable GPIO after disabling outputs
- Add MAINTAINERS entry
- Depend on GPIOLIB and OF
- Add support for IN supply
---
MAINTAINERS | 7 +
drivers/regulator/Kconfig | 10 +-
drivers/regulator/Makefile | 1 +
drivers/regulator/max20086-regulator.c | 333 +++++++++++++++++++++++++
4 files changed, 350 insertions(+), 1 deletion(-)
create mode 100644 drivers/regulator/max20086-regulator.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 79fd8a012893..2891e71c0b9e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11577,6 +11577,13 @@ S: Maintained
F: Documentation/devicetree/bindings/power/supply/maxim,max17042.yaml
F: drivers/power/supply/max17042_battery.c
+MAXIM MAX20086 CAMERA POWER PROTECTOR DRIVER
+M: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
+L: linux-kernel@xxxxxxxxxxxxxxx
+S: Maintained
+F: Documentation/devicetree/bindings/regulator/maxim,max20086.yaml
+F: drivers/regulator/max20086-regulator.c
+
MAXIM MAX77650 PMIC MFD DRIVER
M: Bartosz Golaszewski <brgl@xxxxxxxx>
L: linux-kernel@xxxxxxxxxxxxxxx
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 6be9b1c8a615..dd5c70fe7438 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -636,6 +636,15 @@ config REGULATOR_MAX8998
via I2C bus. The provided regulator is suitable for S3C6410
and S5PC1XX chips to control VCC_CORE and VCC_USIM voltages.
+config REGULATOR_MAX20086
+ tristate "Maxim MAX20086-MAX20089 Camera Power Protectors"
+ depends on I2C
+ select REGMAP_I2C
+ help
+ This driver controls a Maxim MAX20086-MAX20089 camera power
+ protectorvia I2C bus. The regulator has 2 or 4 outputs depending on
+ the device model. This driver is only capable to turn on/off them.
+
config REGULATOR_MAX77686
tristate "Maxim 77686 regulator"
depends on MFD_MAX77686 || COMPILE_TEST
@@ -1415,4 +1424,3 @@ config REGULATOR_QCOM_LABIBB
for LCD display panel.
endif
-
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index b07d2a22df0b..a9e986231eb8 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -78,6 +78,7 @@ obj-$(CONFIG_REGULATOR_MAX8952) += max8952.o
obj-$(CONFIG_REGULATOR_MAX8973) += max8973-regulator.o
obj-$(CONFIG_REGULATOR_MAX8997) += max8997-regulator.o
obj-$(CONFIG_REGULATOR_MAX8998) += max8998.o
+obj-$(CONFIG_REGULATOR_MAX20086) += max20086-regulator.o
obj-$(CONFIG_REGULATOR_MAX77686) += max77686-regulator.o
obj-$(CONFIG_REGULATOR_MAX77693) += max77693-regulator.o
obj-$(CONFIG_REGULATOR_MAX77802) += max77802-regulator.o
diff --git a/drivers/regulator/max20086-regulator.c b/drivers/regulator/max20086-regulator.c
new file mode 100644
index 000000000000..8edefb0090c4
--- /dev/null
+++ b/drivers/regulator/max20086-regulator.c
@@ -0,0 +1,333 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * max20086-regulator.c - MAX20086-MAX20089 camera power protector driver
+ *
+ * Copyright (C) 2022 Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxx>
+ * Copyright (C) 2018 Avnet, Inc.
+ */
+
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/slab.h>
+
+/* Register Offset */
+#define MAX20086_REG_MASK 0x00
+#define MAX20086_REG_CONFIG 0x01
+#define MAX20086_REG_ID 0x02
+#define MAX20086_REG_STAT1 0x03
+#define MAX20086_REG_STAT2_L 0x04
+#define MAX20086_REG_STAT2_H 0x05
+#define MAX20086_REG_ADC1 0x06
+#define MAX20086_REG_ADC2 0x07
+#define MAX20086_REG_ADC3 0x08
+#define MAX20086_REG_ADC4 0x09
+
+/* DEVICE IDs */
+#define MAX20086_DEVICE_ID_MAX20086 0x40
+#define MAX20086_DEVICE_ID_MAX20087 0x20
+#define MAX20086_DEVICE_ID_MAX20088 0x10
+#define MAX20086_DEVICE_ID_MAX20089 0x00
+#define DEVICE_ID_MASK 0xf0
+
+/* Register bits */
+#define MAX20086_EN_MASK 0x0f
+#define MAX20086_EN_OUT1 0x01
+#define MAX20086_EN_OUT2 0x02
+#define MAX20086_EN_OUT3 0x04
+#define MAX20086_EN_OUT4 0x08
+#define MAX20086_INT_DISABLE_ALL 0x3f
+
+#define MAX20086_MAX_REGULATORS 4
+
+struct max20086_chip_info {
+ u8 id;
+ unsigned int num_outputs;
+};
+
+struct max20086_regulator {
+ struct device_node *of_node;
+ struct regulator_init_data *init_data;
+ const struct regulator_desc *desc;
+ struct regulator_dev *rdev;
+};
+
+struct max20086 {
+ struct device *dev;
+ struct regmap *regmap;
+ struct gpio_desc *gpio_en;
+
+ const struct max20086_chip_info *info;
+ unsigned int num_outputs;
+
+ struct max20086_regulator regulators[MAX20086_MAX_REGULATORS];
+};
+
+static const struct regulator_ops max20086_buck_ops = {
+ .enable = regulator_enable_regmap,
+ .disable = regulator_disable_regmap,
+ .is_enabled = regulator_is_enabled_regmap,
+};
+
+#define MAX20086_REGULATOR_DESC(n) \
+{ \
+ .name = max20086_output_names[n], \
+ .supply_name = "in", \
+ .id = (n), \
+ .ops = &max20086_buck_ops, \
+ .type = REGULATOR_VOLTAGE, \
+ .owner = THIS_MODULE, \
+ .enable_reg = MAX20086_REG_CONFIG, \
+ .enable_mask = (1 << (n)), \
+ .enable_val = (1 << (n)), \
+ .disable_val = 0, \
+}
+
+static const char * const max20086_output_names[] = {
+ "OUT1",
+ "OUT2",
+ "OUT3",
+ "OUT4",
+};
+
+static const struct regulator_desc max20086_regulators[] = {
+ MAX20086_REGULATOR_DESC(0),
+ MAX20086_REGULATOR_DESC(1),
+ MAX20086_REGULATOR_DESC(2),
+ MAX20086_REGULATOR_DESC(3),
+};
+
+static int max20086_regulators_register(struct max20086 *chip)
+{
+ unsigned int i;
+
+ for (i = 0; i < chip->num_outputs; i++) {
+ struct max20086_regulator *reg = &chip->regulators[i];
+ struct regulator_config config = { };
+ struct regulator_dev *rdev;
+
+ config.init_data = reg->init_data;
+ config.dev = chip->dev;
+ config.driver_data = chip;
+ config.regmap = chip->regmap;
+ config.of_node = reg->of_node;
+
+ rdev = devm_regulator_register(chip->dev, reg->desc, &config);
+ if (IS_ERR(rdev)) {
+ dev_err(chip->dev,
+ "Failed to register regulator output %s\n",
+ reg->desc->name);
+ return PTR_ERR(rdev);
+ }
+
+ reg->rdev = rdev;
+ }
+
+ return 0;
+}
+
+static int max20086_parse_regulators_dt(struct max20086 *chip)
+{
+ struct of_regulator_match matches[MAX20086_MAX_REGULATORS] = { };
+ struct device_node *node;
+ unsigned int i;
+ unsigned int n;
+ int num;
+
+ node = of_get_child_by_name(chip->dev->of_node, "regulators");
+ if (!node) {
+ dev_err(chip->dev, "regulators node not found\n");
+ return PTR_ERR(node);
+ }
+
+ for (i = 0; i < chip->info->num_outputs; ++i)
+ matches[i].name = max20086_output_names[i];
+
+ num = of_regulator_match(chip->dev, node, matches,
+ chip->info->num_outputs);
+ of_node_put(node);
+ if (num <= 0) {
+ dev_err(chip->dev, "Failed to match regulators\n");
+ return -EINVAL;
+ }
+
+ chip->num_outputs = num;
+
+ for (i = 0, n = 0; i < chip->num_outputs; i++) {
+ struct max20086_regulator *reg = &chip->regulators[n];
+
+ if (!matches[i].init_data)
+ continue;
+
+ reg->init_data = matches[i].init_data;
+ reg->of_node = matches[i].of_node;
+ reg->desc = &max20086_regulators[i];
+
+ dev_dbg(chip->dev, "Found output %s\n", reg->desc->name);
+ n++;
+ }
+
+ return 0;
+}
+
+static int max20086_detect(struct max20086 *chip)
+{
+ unsigned int data;
+ int ret;
+
+ ret = regmap_read(chip->regmap, MAX20086_REG_ID, &data);
+ if (ret < 0) {
+ dev_err(chip->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
+ return ret;
+ }
+
+ if ((data & DEVICE_ID_MASK) != chip->info->id) {
+ dev_err(chip->dev, "Invalid device ID 0x%02x\n", data);
+ return -ENXIO;
+ }
+
+ return 0;
+}
+
+static bool max20086_gen_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case MAX20086_REG_MASK:
+ case MAX20086_REG_CONFIG:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static const struct regmap_config max20086_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .writeable_reg = max20086_gen_is_writeable_reg,
+ .max_register = 0x9,
+ .cache_type = REGCACHE_NONE,
+};
+
+static int max20086_i2c_probe(struct i2c_client *i2c)
+{
+ struct max20086 *chip;
+ int ret;
+
+ chip = devm_kzalloc(&i2c->dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ chip->dev = &i2c->dev;
+ chip->info = device_get_match_data(chip->dev);
+
+ i2c_set_clientdata(i2c, chip);
+
+ chip->regmap = devm_regmap_init_i2c(i2c, &max20086_regmap_config);
+ if (IS_ERR(chip->regmap)) {
+ ret = PTR_ERR(chip->regmap);
+ dev_err(chip->dev, "Failed to allocate register map: %d\n", ret);
+ return ret;
+ }
+
+ ret = max20086_parse_regulators_dt(chip);
+ if (ret < 0)
+ return ret;
+
+ ret = max20086_detect(chip);
+ if (ret < 0)
+ return ret;
+
+ /* Turn off all outputs. */
+ ret = regmap_update_bits(chip->regmap, MAX20086_REG_CONFIG,
+ MAX20086_EN_MASK, 0);
+ if (ret < 0) {
+ dev_err(chip->dev, "Failed to disable outputs: %d\n", ret);
+ return ret;
+ }
+
+ /* Until IRQ support is added, just disable all interrupts. */
+ ret = regmap_update_bits(chip->regmap, MAX20086_REG_MASK,
+ MAX20086_INT_DISABLE_ALL,
+ MAX20086_INT_DISABLE_ALL);
+ if (ret < 0) {
+ dev_err(chip->dev, "Failed to disable interrupts: %d\n", ret);
+ return ret;
+ }
+
+ /* Get the chip out of low-power shutdown state. */
+ chip->gpio_en = devm_gpiod_get(chip->dev, "enable", GPIOD_OUT_HIGH);
+ if (IS_ERR(chip->gpio_en)) {
+ ret = PTR_ERR(chip->gpio_en);
+ dev_err(chip->dev, "Failed to get enable GPIO: %d\n", ret);
+ return ret;
+ }
+
+ ret = max20086_regulators_register(chip);
+ if (ret < 0) {
+ dev_err(chip->dev, "Failed to register regulators: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct i2c_device_id max20086_i2c_id[] = {
+ { "max20086" },
+ { "max20087" },
+ { "max20088" },
+ { "max20089" },
+ { /* Sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(i2c, max20086_i2c_id);
+
+static const struct of_device_id max20086_dt_ids[] = {
+ {
+ .compatible = "maxim,max20086",
+ .data = &(const struct max20086_chip_info) {
+ .id = MAX20086_DEVICE_ID_MAX20086,
+ .num_outputs = 4,
+ }
+ }, {
+ .compatible = "maxim,max20087",
+ .data = &(const struct max20086_chip_info) {
+ .id = MAX20086_DEVICE_ID_MAX20087,
+ .num_outputs = 4,
+ }
+ }, {
+ .compatible = "maxim,max20088",
+ .data = &(const struct max20086_chip_info) {
+ .id = MAX20086_DEVICE_ID_MAX20088,
+ .num_outputs = 2,
+ }
+ }, {
+ .compatible = "maxim,max20089",
+ .data = &(const struct max20086_chip_info) {
+ .id = MAX20086_DEVICE_ID_MAX20089,
+ .num_outputs = 2,
+ }
+ },
+ { /* Sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(of, max20086_dt_ids);
+
+static struct i2c_driver max20086_regulator_driver = {
+ .driver = {
+ .name = "max20086",
+ .of_match_table = of_match_ptr(max20086_dt_ids),
+ },
+ .probe_new = max20086_i2c_probe,
+ .id_table = max20086_i2c_id,
+};
+
+module_i2c_driver(max20086_regulator_driver);
+
+MODULE_AUTHOR("Watson Chow <watson.chow@xxxxxxxxx>");
+MODULE_DESCRIPTION("MAX20086-MAX20089 Camera Power Protector Driver");
+MODULE_LICENSE("GPL");
--
Regards,
Laurent Pinchart