Utilize the integrated 10-bit ADC in Max5970/Max5978 to enable voltage
and current monitoring. This feature is seamlessly integrated through
the hwmon subsystem.
Signed-off-by: Naresh Solanki <[email protected]>
---
Change in V6:
- Remove unrelated change
- Add necessary return value check
- Remove unneeded NULL check
Changes in V5:
- Simplify memory allocation for rdevs
Changes in V4:
- Use IS_REACHABLE
- Use rdevs array for hwmon ops.
- Remove duplicate i2c_set_clientdata
Changes in V3:
- Update signed-off
- Add break
- Update hwmon dev register name to max5970
- Remove changes in Kconfig.
Changes in V2:
- default case added for switch statement
- Add dependency on HWMON
---
drivers/regulator/max5970-regulator.c | 144 +++++++++++++++++++++++++-
1 file changed, 143 insertions(+), 1 deletion(-)
diff --git a/drivers/regulator/max5970-regulator.c b/drivers/regulator/max5970-regulator.c
index b56a174cde3d..56cc56ae63b7 100644
--- a/drivers/regulator/max5970-regulator.c
+++ b/drivers/regulator/max5970-regulator.c
@@ -10,6 +10,7 @@
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/err.h>
+#include <linux/hwmon.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/of.h>
@@ -32,6 +33,132 @@ enum max597x_regulator_id {
MAX597X_SW1,
};
+static int max5970_read_adc(struct regmap *regmap, int reg, long *val)
+{
+ u8 reg_data[2];
+ int ret;
+
+ ret = regmap_bulk_read(regmap, reg, ®_data[0], 2);
+ if (ret < 0)
+ return ret;
+
+ *val = (reg_data[0] << 2) | (reg_data[1] & 3);
+
+ return 0;
+}
+
+static int max5970_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct regulator_dev **rdevs = dev_get_drvdata(dev);
+ struct max5970_regulator *ddata = rdev_get_drvdata(rdevs[channel]);
+ struct regmap *regmap = ddata->regmap;
+ int ret;
+
+ switch (type) {
+ case hwmon_curr:
+ switch (attr) {
+ case hwmon_curr_input:
+ ret = max5970_read_adc(regmap, MAX5970_REG_CURRENT_H(channel), val);
+ if (ret < 0)
+ return ret;
+ /*
+ * Calculate current from ADC value, IRNG range & shunt resistor value.
+ * ddata->irng holds the voltage corresponding to the maximum value the
+ * 10-bit ADC can measure.
+ * To obtain the output, multiply the ADC value by the IRNG range (in
+ * millivolts) and then divide it by the maximum value of the 10-bit ADC.
+ */
+ *val = (*val * ddata->irng) >> 10;
+ /* Convert the voltage meansurement across shunt resistor to current */
+ *val = (*val * 1000) / ddata->shunt_micro_ohms;
+ return 0;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ case hwmon_in:
+ switch (attr) {
+ case hwmon_in_input:
+ ret = max5970_read_adc(regmap, MAX5970_REG_VOLTAGE_H(channel), val);
+ if (ret < 0)
+ return ret;
+ /*
+ * Calculate voltage from ADC value and MON range.
+ * ddata->mon_rng holds the voltage corresponding to the maximum value the
+ * 10-bit ADC can measure.
+ * To obtain the output, multiply the ADC value by the MON range (in
+ * microvolts) and then divide it by the maximum value of the 10-bit ADC.
+ */
+ *val = mul_u64_u32_shr(*val, ddata->mon_rng, 10);
+ /* uV to mV */
+ *val = *val / 1000;
+ return 0;
+ default:
+ return -EOPNOTSUPP;
+ }
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static umode_t max5970_is_visible(const void *data,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ struct regulator_dev **rdevs = (struct regulator_dev **)data;
+ struct max5970_regulator *ddata;
+
+ if (channel >= MAX5970_NUM_SWITCHES || !rdevs[channel])
+ return 0;
+
+ ddata = rdev_get_drvdata(rdevs[channel]);
+
+ if (channel >= ddata->num_switches)
+ return 0;
+
+ switch (type) {
+ case hwmon_in:
+ switch (attr) {
+ case hwmon_in_input:
+ return 0444;
+ default:
+ break;
+ }
+ break;
+ case hwmon_curr:
+ switch (attr) {
+ case hwmon_curr_input:
+ /* Current measurement requires knowledge of the shunt resistor value. */
+ if (ddata->shunt_micro_ohms)
+ return 0444;
+ break;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+ return 0;
+}
+
+static const struct hwmon_ops max5970_hwmon_ops = {
+ .is_visible = max5970_is_visible,
+ .read = max5970_read,
+};
+
+static const struct hwmon_channel_info *max5970_info[] = {
+ HWMON_CHANNEL_INFO(in, HWMON_I_INPUT, HWMON_I_INPUT),
+ HWMON_CHANNEL_INFO(curr, HWMON_C_INPUT, HWMON_C_INPUT),
+ NULL
+};
+
+static const struct hwmon_chip_info max5970_chip_info = {
+ .ops = &max5970_hwmon_ops,
+ .info = max5970_info,
+};
+
static int max597x_uvp_ovp_check_mode(struct regulator_dev *rdev, int severity)
{
int ret, reg;
@@ -431,7 +558,8 @@ static int max597x_regulator_probe(struct platform_device *pdev)
struct i2c_client *i2c = to_i2c_client(pdev->dev.parent);
struct regulator_config config = { };
struct regulator_dev *rdev;
- struct regulator_dev *rdevs[MAX5970_NUM_SWITCHES];
+ struct regulator_dev **rdevs = NULL;
+ struct device *hwmon_dev;
int num_switches;
int ret, i;
@@ -442,6 +570,11 @@ static int max597x_regulator_probe(struct platform_device *pdev)
if (!max597x)
return -ENOMEM;
+ rdevs = devm_kcalloc(&i2c->dev, MAX5970_NUM_SWITCHES, sizeof(struct regulator_dev *),
+ GFP_KERNEL);
+ if (!rdevs)
+ return -ENOMEM;
+
i2c_set_clientdata(i2c, max597x);
if (of_device_is_compatible(i2c->dev.of_node, "maxim,max5978"))
@@ -485,6 +618,15 @@ static int max597x_regulator_probe(struct platform_device *pdev)
max597x->shunt_micro_ohms[i] = data->shunt_micro_ohms;
}
+ if (IS_REACHABLE(CONFIG_HWMON)) {
+ hwmon_dev = devm_hwmon_device_register_with_info(&i2c->dev, "max5970", rdevs,
+ &max5970_chip_info, NULL);
+ if (IS_ERR(hwmon_dev)) {
+ return dev_err_probe(&i2c->dev, PTR_ERR(hwmon_dev),
+ "Unable to register hwmon device\n");
+ }
+ }
+
if (i2c->irq) {
ret =
max597x_setup_irq(&i2c->dev, i2c->irq, rdevs, num_switches,
base-commit: e95d9ba0eb4ef2f9f7fa0451c3ad4f77c685538d
--
2.41.0
Remove redundant/duplicate line.
Signed-off-by: Naresh Solanki <[email protected]>
---
drivers/regulator/max5970-regulator.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/drivers/regulator/max5970-regulator.c b/drivers/regulator/max5970-regulator.c
index 56cc56ae63b7..bc88a40a88d4 100644
--- a/drivers/regulator/max5970-regulator.c
+++ b/drivers/regulator/max5970-regulator.c
@@ -584,7 +584,6 @@ static int max597x_regulator_probe(struct platform_device *pdev)
else
return -ENODEV;
- i2c_set_clientdata(i2c, max597x);
num_switches = max597x->num_switches;
for (i = 0; i < num_switches; i++) {
--
2.41.0
On 10/27/23 08:28, Naresh Solanki wrote:
> Utilize the integrated 10-bit ADC in Max5970/Max5978 to enable voltage
> and current monitoring. This feature is seamlessly integrated through
> the hwmon subsystem.
>
> Signed-off-by: Naresh Solanki <[email protected]>
Acked-by: Guenter Roeck <[email protected]>
On Fri, 27 Oct 2023 15:28:28 +0000, Naresh Solanki wrote:
> Utilize the integrated 10-bit ADC in Max5970/Max5978 to enable voltage
> and current monitoring. This feature is seamlessly integrated through
> the hwmon subsystem.
>
>
Applied to
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-next
Thanks!
[1/2] regulator (max5970): Add hwmon support
commit: f5afdd13ed6c643c7243e685fe3cf5484b3fdfae
[2/2] regulator (max5970): Remove duplicate line
commit: 804bf07a1f726d4fe391d21b24a68ffc2381ba89
All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying
to this mail.
Thanks,
Mark