[PATCH v5 12/16] regulator: bd71828: Add GPIO based run-level control for regulators

From: Matti Vaittinen
Date: Mon Nov 18 2019 - 02:00:07 EST


Bucks 1,2,6 and 7 on ROHM BD71828 can be either controlled as
individual regulartors - or they can be grouped to a group of
regulators that are controlled by 'run levels'. This can be
done via I2C. Each regulator can be assigned a voltage and
enable/disable status for each run-level. These statuses are
also changeable via I2C.

Run-levels can then be changed either by I2C or GPIO. This
control mechanism is selected by data in one time programmable
area (during production) and can't be changed later.

Allow:
- configuring regulators to be controlled via run-levels
- allow getting/setting the current run-level via in-kernel API
using either GPIO or I2C underneath
- Allow run-time changes to run-level voltages via in-kernel API
Signed-off-by: Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx>
---

No changes from v4


drivers/regulator/bd71828-regulator.c | 561 +++++++++++++++++++++++++-
include/linux/mfd/rohm-bd71828.h | 5 +
2 files changed, 556 insertions(+), 10 deletions(-)

diff --git a/drivers/regulator/bd71828-regulator.c b/drivers/regulator/bd71828-regulator.c
index b113cec41969..411e6a297da6 100644
--- a/drivers/regulator/bd71828-regulator.c
+++ b/drivers/regulator/bd71828-regulator.c
@@ -4,8 +4,10 @@
//

#include <linux/delay.h>
+#include <linux/device.h>
#include <linux/err.h>
#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mfd/rohm-bd71828.h>
@@ -17,16 +19,37 @@
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>

+/* Drivers should not do this. But we provide this custom kernel interface
+ * for users to switch the run-level. Hence we need to get the rdev from
+ * struct regulator
+ */
+#include "internal.h"
+
+#define MAX_GPIO_DVS_BUCKS 4
+#define DVS_RUN_LEVELS 4
+#define BD71828_RUNLVL_DEFAULT_UV 500000
+
struct reg_init {
unsigned int reg;
unsigned int mask;
unsigned int val;
};
+
+struct run_lvl_ctrl {
+ unsigned int voltage;
+ bool enabled;
+};
+
struct bd71828_regulator_data {
struct regulator_desc desc;
- const struct rohm_dvs_config dvs;
+ struct rohm_dvs_config dvs;
const struct reg_init *reg_inits;
int reg_init_amnt;
+ struct run_lvl_ctrl run_lvl[DVS_RUN_LEVELS];
+ struct mutex dvs_lock;
+ struct gpio_descs *gps;
+ struct regmap *regmap;
+ bool allow_runlvl;
};

static const struct reg_init buck1_inits[] = {
@@ -41,6 +64,14 @@ static const struct reg_init buck1_inits[] = {
},
};

+static const struct reg_init buck1_gpio_inits[] = {
+ {
+ .reg = BD71828_REG_PS_CTRL_1,
+ .mask = BD71828_MASK_DVS_BUCK1_CTRL,
+ .val = BD71828_DVS_BUCK1_USE_RUNLVL,
+ },
+};
+
static const struct reg_init buck2_inits[] = {
{
.reg = BD71828_REG_PS_CTRL_1,
@@ -49,6 +80,14 @@ static const struct reg_init buck2_inits[] = {
},
};

+static const struct reg_init buck2_gpio_inits[] = {
+ {
+ .reg = BD71828_REG_PS_CTRL_1,
+ .mask = BD71828_MASK_DVS_BUCK2_CTRL,
+ .val = BD71828_DVS_BUCK2_USE_RUNLVL,
+ },
+};
+
static const struct reg_init buck6_inits[] = {
{
.reg = BD71828_REG_PS_CTRL_1,
@@ -57,6 +96,14 @@ static const struct reg_init buck6_inits[] = {
},
};

+static const struct reg_init buck6_gpio_inits[] = {
+ {
+ .reg = BD71828_REG_PS_CTRL_1,
+ .mask = BD71828_MASK_DVS_BUCK6_CTRL,
+ .val = BD71828_DVS_BUCK6_USE_RUNLVL,
+ },
+};
+
static const struct reg_init buck7_inits[] = {
{
.reg = BD71828_REG_PS_CTRL_1,
@@ -65,6 +112,14 @@ static const struct reg_init buck7_inits[] = {
},
};

+static const struct reg_init buck7_gpio_inits[] = {
+ {
+ .reg = BD71828_REG_PS_CTRL_1,
+ .mask = BD71828_MASK_DVS_BUCK7_CTRL,
+ .val = BD71828_DVS_BUCK7_USE_RUNLVL,
+ },
+};
+
static const struct regulator_linear_range bd71828_buck1267_volts[] = {
REGULATOR_LINEAR_RANGE(500000, 0x00, 0xef, 6250),
REGULATOR_LINEAR_RANGE(2000000, 0xf0, 0xff, 0),
@@ -155,6 +210,83 @@ static int buck_set_hw_dvs_levels(struct device_node *np,
return rohm_regulator_set_dvs_levels(&data->dvs, np, desc, cfg->regmap);
}

+static int set_runlevel_voltage(struct regmap *regmap,
+ const struct regulator_desc *desc,
+ unsigned int uv, unsigned int level)
+{
+ int i, ret = -EINVAL;
+ /*
+ * RUN level registers are next to vsel_reg. RUN0 reg is next, then
+ * is the RUN 1 reg and so on...
+ */
+ u8 reg = desc->vsel_reg + level + 1;
+ u8 mask = BD71828_MASK_BUCK1267_VOLT;
+
+ for (i = 0; i < desc->n_voltages; i++) {
+ ret = regulator_desc_list_voltage_linear_range(desc, i);
+ if (ret < 0)
+ continue;
+ if (ret == uv) {
+ i <<= ffs(desc->vsel_mask) - 1;
+ ret = regmap_update_bits(regmap, reg, mask, i);
+ break;
+ }
+ }
+ return ret;
+}
+
+static int buck_set_runlvl_hw_dvs_levels(struct device_node *np,
+ const struct regulator_desc *desc,
+ struct regulator_config *cfg)
+{
+ struct bd71828_regulator_data *data;
+ /* Default to 'disabled' (0 uV) if no property found */
+ uint32_t uv[DVS_RUN_LEVELS] = {0};
+ int i, ret;
+ const char *prop = "rohm,dvs-runlevel-microvolts";
+ /* On BD71828 the RUN level control reg is next to enable reg */
+ u8 en_reg = desc->enable_reg + 1;
+ u8 en_masks[DVS_RUN_LEVELS] = { BD71828_MASK_RUN0_EN,
+ BD71828_MASK_RUN1_EN,
+ BD71828_MASK_RUN2_EN,
+ BD71828_MASK_RUN3_EN };
+
+ data = container_of(desc, struct bd71828_regulator_data, desc);
+
+ ret = of_property_read_variable_u32_array(np, prop, uv, 1,
+ DVS_RUN_LEVELS);
+ if (ret < 0 && ret != -EINVAL)
+ return ret;
+
+ mutex_lock(&data->dvs_lock);
+ for (i = 0; i < DVS_RUN_LEVELS; i++) {
+ if (uv[i]) {
+ data->run_lvl[i].voltage = uv[i];
+ data->run_lvl[i].enabled = true;
+
+ ret = set_runlevel_voltage(cfg->regmap, desc, uv[i], i);
+ if (ret)
+ goto unlock_out;
+
+ ret = regmap_update_bits(cfg->regmap, en_reg,
+ en_masks[i], en_masks[i]);
+ } else {
+ data->run_lvl[i].voltage = BD71828_RUNLVL_DEFAULT_UV;
+ ret = regmap_update_bits(cfg->regmap, en_reg,
+ en_masks[i], 0);
+ }
+ if (ret)
+ goto unlock_out;
+ }
+
+ ret = rohm_regulator_set_dvs_levels(&data->dvs, np, desc, cfg->regmap);
+
+unlock_out:
+ mutex_unlock(&data->dvs_lock);
+
+ return ret;
+}
+
static int ldo6_parse_dt(struct device_node *np,
const struct regulator_desc *desc,
struct regulator_config *cfg)
@@ -189,6 +321,265 @@ static int ldo6_parse_dt(struct device_node *np,
return 0;
}

+static int bd71828_dvs_gpio_set_run_level(struct bd71828_regulator_data *rd,
+ int val)
+{
+ DECLARE_BITMAP(values, 2);
+
+ if (rd->gps->ndescs != 2)
+ return -EINVAL;
+
+ if (val < 0 || val > 3)
+ return -EINVAL;
+
+ values[0] = val;
+
+ return gpiod_set_array_value_cansleep(rd->gps->ndescs, rd->gps->desc,
+ rd->gps->info, values);
+}
+
+/* Get current run level when RUN levels are controlled using I2C */
+static int bd71828_dvs_i2c_set_run_level(struct regmap *regmap,
+ int lvl)
+{
+ unsigned int reg;
+
+ reg = lvl << (ffs(BD71828_MASK_RUN_LVL_CTRL) - 1);
+
+ return regmap_update_bits(regmap, BD71828_REG_PS_CTRL_3,
+ BD71828_MASK_RUN_LVL_CTRL, reg);
+}
+/* Get current run level when RUN levels are controlled using I2C */
+static int bd71828_dvs_i2c_get_run_level(struct regmap *regmap,
+ struct bd71828_regulator_data *rd)
+{
+ int ret;
+ unsigned int val;
+
+ ret = regmap_read(regmap, BD71828_REG_PS_CTRL_3, &val);
+ if (ret)
+ return ret;
+
+ ret = (val & BD71828_MASK_RUN_LVL_CTRL);
+ ret >>= ffs(BD71828_MASK_RUN_LVL_CTRL) - 1;
+
+ return ret;
+}
+
+/* Get current RUN level when run levels are controlled by GPIO */
+static int bd71828_dvs_gpio_get_run_level(struct bd71828_regulator_data *rd)
+{
+ int run_level;
+ int ret;
+ DECLARE_BITMAP(values, 2);
+
+ values[0] = 0;
+
+ if (rd->gps->ndescs != 2)
+ return -EINVAL;
+
+ ret = gpiod_get_array_value_cansleep(rd->gps->ndescs, rd->gps->desc,
+ rd->gps->info, values);
+ if (ret)
+ return ret;
+
+ run_level = values[0];
+
+ return run_level;
+}
+
+/*
+ * To be used when BD71828 regulator is controlled by RUN levels
+ * via I2C instead of GPIO
+ */
+static int bd71828_dvs_i2c_is_enabled(struct regulator_dev *rdev)
+{
+ struct bd71828_regulator_data *data = rdev_get_drvdata(rdev);
+ int ret;
+
+ mutex_lock(&data->dvs_lock);
+ ret = bd71828_dvs_i2c_get_run_level(rdev->regmap, data);
+ if (ret < 0)
+ goto unlock_out;
+
+ ret = data->run_lvl[ret].enabled;
+
+unlock_out:
+ mutex_unlock(&data->dvs_lock);
+
+ return ret;
+}
+
+/*
+ * To be used when BD71828 regulator is controlled by RUN levels
+ * via GPIO
+ */
+static int bd71828_dvs_gpio_is_enabled(struct regulator_dev *rdev)
+{
+ struct bd71828_regulator_data *data = rdev_get_drvdata(rdev);
+ int ret;
+
+ mutex_lock(&data->dvs_lock);
+ ret = bd71828_dvs_gpio_get_run_level(data);
+ if (ret < 0 || ret >= DVS_RUN_LEVELS)
+ goto unlock_out;
+
+ ret = data->run_lvl[ret].enabled;
+
+unlock_out:
+ mutex_unlock(&data->dvs_lock);
+
+ return ret;
+}
+
+/*
+ * To be used when BD71828 regulator is controlled by RUN levels
+ * via I2C instead of GPIO
+ */
+static int bd71828_dvs_i2c_get_voltage(struct regulator_dev *rdev)
+{
+ int ret;
+ struct bd71828_regulator_data *data = rdev_get_drvdata(rdev);
+
+ mutex_lock(&data->dvs_lock);
+ ret = bd71828_dvs_i2c_get_run_level(rdev->regmap, data);
+ if (ret < 0)
+ goto unlock_out;
+
+ ret = data->run_lvl[ret].voltage;
+
+unlock_out:
+ mutex_unlock(&data->dvs_lock);
+
+ return ret;
+}
+
+/*
+ * To be used when BD71828 regulator is controlled by RUN levels
+ * via GPIO
+ */
+static int bd71828_dvs_gpio_get_voltage(struct regulator_dev *rdev)
+{
+ int ret;
+ struct bd71828_regulator_data *data = rdev_get_drvdata(rdev);
+
+ mutex_lock(&data->dvs_lock);
+ ret = bd71828_dvs_gpio_get_run_level(data);
+ if (ret < 0 || DVS_RUN_LEVELS <= ret)
+ goto unlock_out;
+
+ ret = data->run_lvl[ret].voltage;
+
+unlock_out:
+ mutex_unlock(&data->dvs_lock);
+
+ return ret;
+}
+
+/**
+ * bd71828_set_runlevel_voltage - change run-level voltage
+ *
+ * @regulator: pointer to regulator for which the run-level voltage is changed
+ * @uv: New voltage for run-level in micro volts
+ * @level: run-level for which the voltage is to be changed
+ *
+ * Changes the run-level voltage for given regulator
+ */
+int bd71828_set_runlevel_voltage(struct regulator *regulator, unsigned int uv,
+ unsigned int level)
+{
+ struct regulator_dev *rdev = regulator->rdev;
+ struct bd71828_regulator_data *data = rdev_get_drvdata(rdev);
+ int ret;
+
+ if (!data || !data->allow_runlvl)
+ return -EINVAL;
+
+ mutex_lock(&data->dvs_lock);
+ ret = set_runlevel_voltage(rdev->regmap, rdev->desc, uv, level);
+ mutex_unlock(&data->dvs_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL(bd71828_set_runlevel_voltage);
+
+/**
+ * bd71828_set_runlevel - change system run-level.
+ *
+ * @regulator: pointer to one of the BD71828 regulators obtained by
+ * call to regulator_get
+ * @level: New run-level the system should enter
+ *
+ * Changes the system to run-level which was given as argument. This
+ * operation will change state of all regulators which are set to be
+ * controlled by run-levels. Note that 'regulator' must point to a
+ * regulator which is controlled by run-levels.
+ */
+int bd71828_set_runlevel(struct regulator *regulator, unsigned int level)
+{
+ struct regulator_dev *rdev = regulator->rdev;
+ struct bd71828_regulator_data *rd = rdev_get_drvdata(rdev);
+
+ if (!rd)
+ return -ENOENT;
+
+ if (!rd || !rd->allow_runlvl)
+ return -EINVAL;
+
+ if (rd->gps)
+ return bd71828_dvs_gpio_set_run_level(rd, level);
+
+ return bd71828_dvs_i2c_set_run_level(rd->regmap, level);
+}
+EXPORT_SYMBOL(bd71828_set_runlevel);
+
+/**
+ * bd71828_get_runlevel - get the current system run-level.
+ *
+ * @regulator: pointer to one of the BD71828 regulators obtained by
+ * call to regulator_get
+ * @level: Pointer to value where current run-level is stored
+ *
+ * Returns the current system run-level. Note that 'regulator' must
+ * point to a regulator which is controlled by run-levels.
+ */
+int bd71828_get_runlevel(struct regulator *regulator, unsigned int *level)
+{
+ struct regulator_dev *rdev = regulator->rdev;
+ struct bd71828_regulator_data *rd = rdev_get_drvdata(rdev);
+ int ret;
+
+ if (!rd)
+ return -ENOENT;
+
+ if (!rd || !rd->allow_runlvl)
+ return -EINVAL;
+
+ if (!rd->gps)
+ ret = bd71828_dvs_i2c_get_run_level(rd->regmap, rd);
+ else
+ ret = bd71828_dvs_gpio_get_run_level(rd);
+
+ if (ret < 0)
+ return ret;
+
+ *level = (unsigned int) ret;
+
+ return 0;
+}
+EXPORT_SYMBOL(bd71828_get_runlevel);
+
+
+static const struct regulator_ops dvs_buck_gpio_ops = {
+ .is_enabled = bd71828_dvs_gpio_is_enabled,
+ .get_voltage = bd71828_dvs_gpio_get_voltage,
+};
+
+static const struct regulator_ops dvs_buck_i2c_ops = {
+ .is_enabled = bd71828_dvs_i2c_is_enabled,
+ .get_voltage = bd71828_dvs_i2c_get_voltage,
+};
+
static const struct regulator_ops bd71828_buck_ops = {
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
@@ -773,6 +1164,127 @@ static const struct bd71828_regulator_data bd71828_rdata[] = {
},
};

+struct bd71828_gpio_cfg {
+ bool use_gpio;
+ unsigned int runlvl;
+ struct gpio_descs *gps;
+};
+
+static void mark_regulator_runlvl_controlled(struct device *dev,
+ struct device_node *np,
+ struct bd71828_gpio_cfg *g)
+{
+ int i;
+
+ for (i = 1; i <= ARRAY_SIZE(bd71828_rdata); i++) {
+ if (!of_node_name_eq(np, bd71828_rdata[i-1].desc.of_match))
+ continue;
+ switch (i) {
+ case 1:
+ case 2:
+ case 6:
+ case 7:
+ g->runlvl |= 1 << (i - 1);
+ dev_dbg(dev, "buck %d runlevel controlled\n", i);
+ break;
+ default:
+ dev_err(dev,
+ "Only bucks 1,2,6,7 support run-level dvs\n");
+ break;
+ }
+ }
+}
+
+static int get_runcontrolled_bucks_dt(struct device *dev,
+ struct bd71828_gpio_cfg *g)
+{
+ struct device_node *np;
+ struct device_node *nproot = dev->of_node;
+ const char *prop = "rohm,dvs-runlvl-ctrl";
+
+ g->runlvl = 0;
+
+ nproot = of_get_child_by_name(nproot, "regulators");
+ if (!nproot) {
+ dev_err(dev, "failed to find regulators node\n");
+ return -ENODEV;
+ }
+ for_each_child_of_node(nproot, np)
+ if (of_property_read_bool(np, prop))
+ mark_regulator_runlvl_controlled(dev, np, g);
+
+ of_node_put(nproot);
+ return 0;
+}
+
+static int check_dt_for_gpio_controls(struct device *d,
+ struct bd71828_gpio_cfg *g)
+{
+ int ret;
+
+ ret = get_runcontrolled_bucks_dt(d, g);
+ if (ret)
+ return ret;
+
+ g->use_gpio = false;
+
+ /* If the run level control is not requested by any bucks we're done */
+ if (!g->runlvl)
+ return 0;
+
+ g->gps = devm_gpiod_get_parent_array(d, "rohm,dvs-vsel", GPIOD_OUT_LOW);
+
+ if (IS_ERR(g->gps)) {
+ ret = PTR_ERR(g->gps);
+ if (ret == -ENOENT)
+ return 0;
+ return ret;
+ }
+
+ if (g->gps->ndescs != 2)
+ return -ENOENT;
+
+ g->use_gpio = true;
+
+ return 0;
+}
+
+static void set_buck_runlvl_controlled(struct rohm_regmap_dev *bd71828,
+ struct bd71828_regulator_data *rd,
+ struct bd71828_gpio_cfg *g)
+{
+ switch (rd->desc.id) {
+ case BD71828_BUCK1:
+ rd->reg_inits = buck1_gpio_inits;
+ break;
+ case BD71828_BUCK2:
+ rd->reg_inits = buck2_gpio_inits;
+ break;
+ case BD71828_BUCK6:
+ rd->reg_inits = buck6_gpio_inits;
+ break;
+ case BD71828_BUCK7:
+ rd->reg_inits = buck7_gpio_inits;
+ break;
+ default:
+ return;
+ }
+
+ /*
+ * Disallow setters. Get voltages/enable states based
+ * on current RUN level
+ */
+ rd->allow_runlvl = true;
+
+ if (g->use_gpio) {
+ rd->gps = g->gps;
+ rd->desc.ops = &dvs_buck_gpio_ops;
+ } else {
+ rd->desc.ops = &dvs_buck_i2c_ops;
+ }
+ rd->desc.of_parse_cb = buck_set_runlvl_hw_dvs_levels;
+}
+
static int bd71828_probe(struct platform_device *pdev)
{
struct rohm_regmap_dev *bd71828;
@@ -780,6 +1292,8 @@ static int bd71828_probe(struct platform_device *pdev)
struct regulator_config config = {
.dev = pdev->dev.parent,
};
+ struct bd71828_gpio_cfg gcfg = {0};
+ struct bd71828_regulator_data *rd;

bd71828 = dev_get_drvdata(pdev->dev.parent);
if (!bd71828) {
@@ -787,30 +1301,57 @@ static int bd71828_probe(struct platform_device *pdev)
return -EINVAL;
}

+ ret = check_dt_for_gpio_controls(pdev->dev.parent, &gcfg);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to get DVS gpio resources\n");
+ return ret;
+ }
+
+ /*
+ * Allocate device data to allow controlling more than one PMICs
+ */
+ rd = devm_kmalloc_array(&pdev->dev, ARRAY_SIZE(bd71828_rdata),
+ sizeof(*rd), GFP_KERNEL);
+ if (!rd)
+ return -ENOMEM;
+
+ dev_set_drvdata(&pdev->dev, rd);
+
+ for (i = 0; i < ARRAY_SIZE(bd71828_rdata); i++) {
+ /* Use bd71828_rdata as template */
+ rd[i] = bd71828_rdata[i];
+
+ mutex_init(&rd[i].dvs_lock);
+ if (gcfg.runlvl & (1 << i))
+ set_buck_runlvl_controlled(bd71828, &rd[i], &gcfg);
+
+ rd[i].regmap = bd71828->regmap;
+ }
+
config.regmap = bd71828->regmap;

for (i = 0; i < ARRAY_SIZE(bd71828_rdata); i++) {
struct regulator_dev *rdev;
- const struct bd71828_regulator_data *rd;

- rd = &bd71828_rdata[i];
+ config.driver_data = &rd[i];
+
rdev = devm_regulator_register(&pdev->dev,
- &rd->desc, &config);
+ &rd[i].desc, &config);
if (IS_ERR(rdev)) {
dev_err(&pdev->dev,
"failed to register %s regulator\n",
- rd->desc.name);
+ rd[i].desc.name);
return PTR_ERR(rdev);
}
- for (j = 0; j < rd->reg_init_amnt; j++) {
+ for (j = 0; j < rd[i].reg_init_amnt; j++) {
ret = regmap_update_bits(bd71828->regmap,
- rd->reg_inits[j].reg,
- rd->reg_inits[j].mask,
- rd->reg_inits[j].val);
+ rd[i].reg_inits[j].reg,
+ rd[i].reg_inits[j].mask,
+ rd[i].reg_inits[j].val);
if (ret) {
dev_err(&pdev->dev,
"regulator %s init failed\n",
- rd->desc.name);
+ rd[i].desc.name);
return ret;
}
}
diff --git a/include/linux/mfd/rohm-bd71828.h b/include/linux/mfd/rohm-bd71828.h
index d013e03f742d..fc0955f0662c 100644
--- a/include/linux/mfd/rohm-bd71828.h
+++ b/include/linux/mfd/rohm-bd71828.h
@@ -418,4 +418,9 @@ enum {
#define BD71828_OUT_TYPE_OPEN_DRAIN 0x0
#define BD71828_OUT_TYPE_CMOS 0x2

+int bd71828_set_runlevel_voltage(struct regulator *regulator, unsigned int uv,
+ unsigned int level);
+int bd71828_set_runlevel(struct regulator *regulator, unsigned int level);
+int bd71828_get_runlevel(struct regulator *regulator, unsigned int *level);
+
#endif /* __LINUX_MFD_BD71828_H__ */
--
2.21.0


--
Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
Kiviharjunlenkki 1E
90220 OULU
FINLAND

~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
Simon says - in Latin please.
~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
Thanks to Simon Glass for the translation =]