[PATCH v2 1/2] regulator: rtmv20: Adds support for Richtek RTMV20 load switch regulator

cy_huang
2020-09-28T07:19:55Z

From: ChiYuan Huang <cy_huang@richtek.com>

Add support for Richtek RTMV20 load switch regulator.

Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
---
v1 to v2
1. Use regcache related APIs when HW disable and enable.
2. Because of regcache, refine the initial properties flow.
3. Change all propertiy name to use dash, not underline.
4. Re-check all the comment lines not to over 80 characters.
5. Same as item 3, and also change all 0/1 properties to boolean type in
dt-binding document.
6. No need is_chip_enabled flag.

---
drivers/regulator/Kconfig | 9 +
drivers/regulator/Makefile | 1 +
drivers/regulator/rtmv20-regulator.c | 392 +++++++++++++++++++++++++++++++++++
3 files changed, 402 insertions(+)
create mode 100644 drivers/regulator/rtmv20-regulator.c

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index de17ef7..400ad4c 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -902,6 +902,15 @@ config REGULATOR_RT5033
RT5033 PMIC. The device supports multiple regulators like
current source, LDO and Buck.

+config REGULATOR_RTMV20
+ tristate "RTMV20 Laser Diode Regulator"
+ depends on I2C
+ select REGMAP_I2C
+ help
+ This driver adds support for the load switch current regulator on
+ the Richtek RTMV20. It can support the load current up to 6A and
+ integrate strobe/vsync/fsin signal to synchronize the IR camera.
+
config REGULATOR_S2MPA01
tristate "Samsung S2MPA01 voltage regulator"
depends on MFD_SEC_CORE
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index d8d3ecf..89a1cb0 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -112,6 +112,7 @@ obj-$(CONFIG_REGULATOR_RK808) += rk808-regulator.o
obj-$(CONFIG_REGULATOR_RN5T618) += rn5t618-regulator.o
obj-$(CONFIG_REGULATOR_ROHM) += rohm-regulator.o
obj-$(CONFIG_REGULATOR_RT5033) += rt5033-regulator.o
+obj-$(CONFIG_REGULATOR_RTMV20) += rtmv20-regulator.o
obj-$(CONFIG_REGULATOR_S2MPA01) += s2mpa01.o
obj-$(CONFIG_REGULATOR_S2MPS11) += s2mps11.o
obj-$(CONFIG_REGULATOR_S5M8767) += s5m8767.o
diff --git a/drivers/regulator/rtmv20-regulator.c b/drivers/regulator/rtmv20-regulator.c
new file mode 100644
index 00000000..1075b10
--- /dev/null
+++ b/drivers/regulator/rtmv20-regulator.c
@@ -0,0 +1,392 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+
+#define RTMV20_REG_DEVINFO 0x00
+#define RTMV20_REG_PULSEDELAY 0x01
+#define RTMV20_REG_PULSEWIDTH 0x03
+#define RTMV20_REG_LDCTRL1 0x05
+#define RTMV20_REG_ESPULSEWIDTH 0x06
+#define RTMV20_REG_ESLDCTRL1 0x08
+#define RTMV20_REG_LBP 0x0A
+#define RTMV20_REG_LDCTRL2 0x0B
+#define RTMV20_REG_FSIN1CTRL1 0x0D
+#define RTMV20_REG_FSIN1CTRL3 0x0F
+#define RTMV20_REG_FSIN2CTRL1 0x10
+#define RTMV20_REG_FSIN2CTRL3 0x12
+#define RTMV20_REG_ENCTRL 0x13
+#define RTMV20_REG_STRBVSYNDLYL 0x29
+#define RTMV20_REG_LDIRQ 0x30
+#define RTMV20_REG_LDSTAT 0x40
+#define RTMV20_REG_LDMASK 0x50
+
+#define RTMV20_VID_MASK GENMASK(7, 4)
+#define RICHTEK_VID 0x80
+#define RTMV20_LDCURR_MASK GENMASK(7, 0)
+#define RTMV20_DELAY_MASK GENMASK(9, 0)
+#define RTMV20_WIDTH_MASK GENMASK(13, 0)
+#define RTMV20_WIDTH2_MASK GENMASK(7, 0)
+#define RTMV20_LBPLVL_MASK GENMASK(3, 0)
+#define RTMV20_LBPEN_MASK BIT(7)
+#define RTMV20_STROBEPOL_MASK BIT(1)
+#define RTMV20_VSYNPOL_MASK BIT(1)
+#define RTMV20_FSINEN_MASK BIT(7)
+#define RTMV20_ESEN_MASK BIT(6)
+#define RTMV20_FSINOUT_MASK BIT(2)
+#define LDENABLE_MASK (BIT(3) | BIT(0))
+
+#define OTPEVT_MASK BIT(4)
+#define SHORTEVT_MASK BIT(3)
+#define OPENEVT_MASK BIT(2)
+#define LBPEVT_MASK BIT(1)
+#define OCPEVT_MASK BIT(0)
+#define FAILEVT_MASK (SHORTEVT_MASK | OPENEVT_MASK | LBPEVT_MASK)
+
+#define RTMV20_LSW_MINUA 0
+#define RTMV20_LSW_MAXUA 6000000
+#define RTMV20_LSW_STEPUA 30000
+
+#define RTMV20_LSW_DEFAULTUA 3000000
+
+#define RTMV20_I2CRDY_TIMEUS 200
+#define RTMV20_CSRDY_TIMEUS 2000
+
+struct rtmv20_priv {
+ struct device *dev;
+ struct regmap *regmap;
+ struct gpio_desc *enable_gpio;
+ struct regulator_dev *rdev;
+};
+
+static int rtmv20_lsw_enable(struct regulator_dev *rdev)
+{
+ struct rtmv20_priv *priv = rdev_get_drvdata(rdev);
+ int ret;
+
+ gpiod_set_value(priv->enable_gpio, 1);
+
+ /* Wait for I2C can be accessed */
+ usleep_range(RTMV20_I2CRDY_TIMEUS, RTMV20_I2CRDY_TIMEUS + 100);
+
+ /* HW re-enable, disable cache only and sync regcache here */
+ regcache_cache_only(priv->regmap, false);
+ ret = regcache_sync(priv->regmap);
+ if (ret)
+ return ret;
+
+ return regulator_enable_regmap(rdev);
+}
+
+static int rtmv20_lsw_disable(struct regulator_dev *rdev)
+{
+ struct rtmv20_priv *priv = rdev_get_drvdata(rdev);
+ int ret;
+
+ ret = regulator_disable_regmap(rdev);
+ if (ret)
+ return ret;
+
+ /* Mark the regcache as dirty and cache only before HW disabled */
+ regcache_cache_only(priv->regmap, true);
+ regcache_mark_dirty(priv->regmap);
+
+ gpiod_set_value(priv->enable_gpio, 0);
+
+ return 0;
+}
+
+static const struct regulator_ops rtmv20_regulator_ops = {
+ .set_current_limit = regulator_set_current_limit_regmap,
+ .get_current_limit = regulator_get_current_limit_regmap,
+ .enable = rtmv20_lsw_enable,
+ .disable = rtmv20_lsw_disable,
+ .is_enabled = regulator_is_enabled_regmap,
+};
+
+static const struct regulator_desc rtmv20_lsw_desc = {
+ .name = "rtmv20,lsw",
+ .of_match = of_match_ptr("lsw"),
+ .type = REGULATOR_CURRENT,
+ .owner = THIS_MODULE,
+ .ops = &rtmv20_regulator_ops,
+ .csel_reg = RTMV20_REG_LDCTRL1,
+ .csel_mask = RTMV20_LDCURR_MASK,
+ .enable_reg = RTMV20_REG_ENCTRL,
+ .enable_mask = LDENABLE_MASK,
+ .enable_time = RTMV20_CSRDY_TIMEUS,
+};
+
+static irqreturn_t rtmv20_irq_handler(int irq, void *data)
+{
+ struct rtmv20_priv *priv = data;
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(priv->regmap, RTMV20_REG_LDIRQ, &val);
+ if (ret) {
+ dev_err(priv->dev, "Failed to get irq flags\n");
+ return IRQ_NONE;
+ }
+
+ if (val & OTPEVT_MASK)
+ regulator_notifier_call_chain(priv->rdev, REGULATOR_EVENT_OVER_TEMP, NULL);
+
+ if (val & OCPEVT_MASK)
+ regulator_notifier_call_chain(priv->rdev, REGULATOR_EVENT_OVER_CURRENT, NULL);
+
+ if (val & FAILEVT_MASK)
+ regulator_notifier_call_chain(priv->rdev, REGULATOR_EVENT_FAIL, NULL);
+
+ return IRQ_HANDLED;
+}
+
+static u32 clamp_to_selector(u32 val, u32 min, u32 max, u32 step)
+{
+ u32 retval = clamp_val(val, min, max);
+
+ return (retval - min) / step;
+}
+
+static int rtmv20_properties_init(struct rtmv20_priv *priv)
+{
+ const struct {
+ const char *name;
+ u32 def;
+ u32 min;
+ u32 max;
+ u32 step;
+ u32 addr;
+ u32 mask;
+ } props[] = {
+ { "ld-pulse-delay-us", 0, 0, 100000, 100, RTMV20_REG_PULSEDELAY,
+ RTMV20_DELAY_MASK },
+ { "ld-pulse-width-us", 1200, 0, 10000, 1, RTMV20_REG_PULSEWIDTH,
+ RTMV20_WIDTH_MASK },
+ { "fsin1-delay-us", 23000, 0, 100000, 100, RTMV20_REG_FSIN1CTRL1,
+ RTMV20_DELAY_MASK },
+ { "fsin1-width-us", 160, 40, 10000, 40, RTMV20_REG_FSIN1CTRL3, RTMV20_WIDTH2_MASK },
+ { "fsin2-delay-us", 23000, 0, 100000, 100, RTMV20_REG_FSIN2CTRL1,
+ RTMV20_DELAY_MASK },
+ { "fsin2-width-us", 160, 40, 10000, 40, RTMV20_REG_FSIN2CTRL3, RTMV20_WIDTH2_MASK },
+ { "es-pulse-width-us", 1200, 0, 10000, 1, RTMV20_REG_ESPULSEWIDTH,
+ RTMV20_WIDTH_MASK },
+ { "es-ld-current-microamp", 3000000, 0, 6000000, 30000, RTMV20_REG_ESLDCTRL1,
+ RTMV20_LDCURR_MASK },
+ { "lbp-level-microvolt", 2700000, 2400000, 3700000, 100000, RTMV20_REG_LBP,
+ RTMV20_LBPLVL_MASK },
+ { "lbp-enable", 0, 0, 1, 1, RTMV20_REG_LBP, RTMV20_LBPEN_MASK },
+ { "strobe-polarity-high", 1, 0, 1, 1, RTMV20_REG_LDCTRL2, RTMV20_STROBEPOL_MASK },
+ { "vsync-polarity-high", 1, 0, 1, 1, RTMV20_REG_LDCTRL2, RTMV20_VSYNPOL_MASK },
+ { "fsin-enable", 0, 0, 1, 1, RTMV20_REG_ENCTRL, RTMV20_FSINEN_MASK },
+ { "fsin-output", 0, 0, 1, 1, RTMV20_REG_ENCTRL, RTMV20_FSINOUT_MASK },
+ { "es-enable", 0, 0, 1, 1, RTMV20_REG_ENCTRL, RTMV20_ESEN_MASK },
+ };
+ int i, ret;
+
+ for (i = 0; i < ARRAY_SIZE(props); i++) {
+ __be16 bval16;
+ u16 val16;
+ u32 temp;
+ int significant_bit = fls(props[i].mask);
+ int shift = ffs(props[i].mask) - 1;
+
+ if (props[i].max > 1) {
+ ret = device_property_read_u32(priv->dev, props[i].name, &temp);
+ if (ret)
+ temp = props[i].def;
+ } else
+ temp = device_property_read_bool(priv->dev, props[i].name);
+
+ temp = clamp_to_selector(temp, props[i].min, props[i].max, props[i].step);
+
+ /* If significant bit is over 8, two byte access, others one */
+ if (significant_bit > 8) {
+ ret = regmap_raw_read(priv->regmap, props[i].addr, &bval16, sizeof(bval16));
+ if (ret)
+ return ret;
+
+ val16 = be16_to_cpu(bval16);
+ val16 &= ~props[i].mask;
+ val16 |= (temp << shift);
+ bval16 = cpu_to_be16(val16);
+
+ ret = regmap_raw_write(priv->regmap, props[i].addr, &bval16,
+ sizeof(bval16));
+ } else {
+ ret = regmap_update_bits(priv->regmap, props[i].addr, props[i].mask,
+ temp << shift);
+ }
+
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int rtmv20_check_chip_exist(struct rtmv20_priv *priv)
+{
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(priv->regmap, RTMV20_REG_DEVINFO, &val);
+ if (ret)
+ return ret;
+
+ if ((val & RTMV20_VID_MASK) != RICHTEK_VID)
+ return -ENODEV;
+
+ return 0;
+}
+
+static bool rtmv20_is_accessible_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case RTMV20_REG_DEVINFO ... RTMV20_REG_STRBVSYNDLYL:
+ case RTMV20_REG_LDIRQ:
+ case RTMV20_REG_LDSTAT:
+ case RTMV20_REG_LDMASK:
+ return true;
+ }
+ return false;
+}
+
+static bool rtmv20_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+ if (reg == RTMV20_REG_LDIRQ || reg == RTMV20_REG_LDSTAT)
+ return true;
+ return false;
+}
+
+static const struct regmap_config rtmv20_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .cache_type = REGCACHE_RBTREE,
+ .max_register = RTMV20_REG_LDMASK,
+
+ .writeable_reg = rtmv20_is_accessible_reg,
+ .readable_reg = rtmv20_is_accessible_reg,
+ .volatile_reg = rtmv20_is_volatile_reg,
+};
+
+static int rtmv20_probe(struct i2c_client *i2c)
+{
+ struct rtmv20_priv *priv;
+ struct regulator_config config = {};
+ int ret;
+
+ priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = &i2c->dev;
+
+ /* Before regmap register, configure HW enable to make I2C accessible */
+ priv->enable_gpio = devm_gpiod_get(&i2c->dev, "enable", GPIOD_OUT_HIGH);
+ if (IS_ERR(priv->enable_gpio)) {
+ dev_err(&i2c->dev, "Failed to get enable gpio\n");
+ return PTR_ERR(priv->enable_gpio);
+ }
+
+ /* Wait for I2C can be accessed */
+ usleep_range(RTMV20_I2CRDY_TIMEUS, RTMV20_I2CRDY_TIMEUS + 100);
+
+ priv->regmap = devm_regmap_init_i2c(i2c, &rtmv20_regmap_config);
+ if (IS_ERR(priv->regmap)) {
+ dev_err(&i2c->dev, "Failed to allocate register map\n");
+ return PTR_ERR(priv->regmap);
+ }
+
+ ret = rtmv20_check_chip_exist(priv);
+ if (ret) {
+ dev_err(&i2c->dev, "Chip vendor info is not matched\n");
+ return ret;
+ }
+
+ ret = rtmv20_properties_init(priv);
+ if (ret) {
+ dev_err(&i2c->dev, "Failed to init properties\n");
+ return ret;
+ }
+
+ /*
+ * keep in shutdown mode to minimize the current consumption
+ * and also mark regcache as dirty
+ */
+ regcache_mark_dirty(priv->regmap);
+ gpiod_set_value(priv->enable_gpio, 0);
+
+ config.dev = &i2c->dev;
+ config.regmap = priv->regmap;
+ config.driver_data = priv;
+ priv->rdev = devm_regulator_register(&i2c->dev, &rtmv20_lsw_desc, &config);
+ if (IS_ERR(priv->rdev)) {
+ dev_err(&i2c->dev, "Failed to register regulator\n");
+ return PTR_ERR(priv->rdev);
+ }
+
+ /* Unmask all events before IRQ registered */
+ ret = regmap_write(priv->regmap, RTMV20_REG_LDMASK, 0);
+ if (ret)
+ return ret;
+
+ return devm_request_threaded_irq(&i2c->dev, i2c->irq, NULL, rtmv20_irq_handler,
+ IRQF_ONESHOT, dev_name(&i2c->dev), priv);
+}
+
+static int __maybe_unused rtmv20_suspend(struct device *dev)
+{
+ struct i2c_client *i2c = to_i2c_client(dev);
+
+ /*
+ * When system suspend, disable irq to prevent interrupt trigger
+ * during I2C bus suspend
+ */
+ disable_irq(i2c->irq);
+ if (device_may_wakeup(dev))
+ enable_irq_wake(i2c->irq);
+
+ return 0;
+}
+
+static int __maybe_unused rtmv20_resume(struct device *dev)
+{
+ struct i2c_client *i2c = to_i2c_client(dev);
+
+ /* Enable irq after I2C bus already resume */
+ enable_irq(i2c->irq);
+ if (device_may_wakeup(dev))
+ disable_irq_wake(i2c->irq);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(rtmv20_pm, rtmv20_suspend, rtmv20_resume);
+
+static const struct of_device_id __maybe_unused rtmv20_of_id[] = {
+ { .compatible = "richtek,rtmv20", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, rtmv20_of_id);
+
+static struct i2c_driver rtmv20_driver = {
+ .driver = {
+ .name = "rtmv20",
+ .of_match_table = of_match_ptr(rtmv20_of_id),
+ .pm = &rtmv20_pm,
+ },
+ .probe_new = rtmv20_probe,
+};
+module_i2c_driver(rtmv20_driver);
+
+MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
+MODULE_DESCRIPTION("Richtek RTMV20 Regulator Driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4