Commit 98ac8af4 authored by Guenter Roeck's avatar Guenter Roeck
Browse files

hwmon: (pmbus/adm1275) Prepare for protected write to PMON_CONFIG 



According to ADI, changing PMON_CONFIG while ADC is running can have
unexpected results. ADI recommends halting the ADC with PMON_CONTROL
before setting PMON_CONFIG and then resume after.

To prepare for this change, rename adm1275_read_pmon_config()
and adm1275_write_pmon_config() to adm1275_read_samples() and
adm1275_write_samples() to more accurately reflect the functionality
of the code. Introduce new function adm1275_write_pmon_config()
and use it for all code writing into the PMON_CONFIG register.

Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230614163605.3688964-2-linux@roeck-us.net


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 37f665ff

drivers/hwmon/pmbus/adm1275.c

+31 −25
Original line number Diff line number Diff line
@@ -173,7 +173,7 @@ static const struct coefficients adm1293_coefficients[] = { 
	[18] = { 7658, 0, -3 },		/* power, 21V, irange200 */

};



static int adm1275_read_pmon_config(const struct adm1275_data *data,

static int adm1275_read_samples(const struct adm1275_data *data,

				struct i2c_client *client, bool is_power)

{

	int shift, ret;
@@ -200,6 +200,21 @@ static int adm1275_read_pmon_config(const struct adm1275_data *data, 
}



static int adm1275_write_pmon_config(const struct adm1275_data *data,

				     struct i2c_client *client, u16 word)

{

	int ret;



	if (data->have_power_sampling)

		ret = i2c_smbus_write_word_data(client, ADM1275_PMON_CONFIG,

						word);

	else

		ret = i2c_smbus_write_byte_data(client, ADM1275_PMON_CONFIG,

						word);



	return ret;

}



static int adm1275_write_samples(const struct adm1275_data *data,

				 struct i2c_client *client,

				 bool is_power, u16 word)

{
@@ -219,14 +234,8 @@ static int adm1275_write_pmon_config(const struct adm1275_data *data, 
		return ret;



	word = (ret & ~mask) | ((word << shift) & mask);

	if (data->have_power_sampling)

		ret = i2c_smbus_write_word_data(client, ADM1275_PMON_CONFIG,

						word);

	else

		ret = i2c_smbus_write_byte_data(client, ADM1275_PMON_CONFIG,

						word);



	return ret;

	return adm1275_write_pmon_config(data, client, word);

}



static int adm1275_read_word_data(struct i2c_client *client, int page,
@@ -321,14 +330,14 @@ static int adm1275_read_word_data(struct i2c_client *client, int page, 
	case PMBUS_VIRT_POWER_SAMPLES:

		if (!data->have_power_sampling)

			return -ENXIO;

		ret = adm1275_read_pmon_config(data, client, true);

		ret = adm1275_read_samples(data, client, true);

		if (ret < 0)

			break;

		ret = BIT(ret);

		break;

	case PMBUS_VIRT_IN_SAMPLES:

	case PMBUS_VIRT_CURR_SAMPLES:

		ret = adm1275_read_pmon_config(data, client, false);

		ret = adm1275_read_samples(data, client, false);

		if (ret < 0)

			break;

		ret = BIT(ret);
@@ -381,14 +390,12 @@ static int adm1275_write_word_data(struct i2c_client *client, int page, int reg, 
		if (!data->have_power_sampling)

			return -ENXIO;

		word = clamp_val(word, 1, ADM1275_SAMPLES_AVG_MAX);

		ret = adm1275_write_pmon_config(data, client, true,

						ilog2(word));

		ret = adm1275_write_samples(data, client, true, ilog2(word));

		break;

	case PMBUS_VIRT_IN_SAMPLES:

	case PMBUS_VIRT_CURR_SAMPLES:

		word = clamp_val(word, 1, ADM1275_SAMPLES_AVG_MAX);

		ret = adm1275_write_pmon_config(data, client, false,

						ilog2(word));

		ret = adm1275_write_samples(data, client, false, ilog2(word));

		break;

	default:

		ret = -ENODATA;
@@ -466,13 +473,14 @@ static const struct i2c_device_id adm1275_id[] = { 
MODULE_DEVICE_TABLE(i2c, adm1275_id);



/* Enable VOUT & TEMP1 if not enabled (disabled by default) */

static int adm1275_enable_vout_temp(struct i2c_client *client, int config)

static int adm1275_enable_vout_temp(struct adm1275_data *data,

				    struct i2c_client *client, int config)

{

	int ret;



	if ((config & ADM1278_PMON_DEFCONFIG) != ADM1278_PMON_DEFCONFIG) {

		config |= ADM1278_PMON_DEFCONFIG;

		ret = i2c_smbus_write_word_data(client, ADM1275_PMON_CONFIG, config);

		ret = adm1275_write_pmon_config(data, client, config);

		if (ret < 0) {

			dev_err(&client->dev, "Failed to enable VOUT/TEMP1 monitoring\n");

			return ret;
@@ -634,7 +642,7 @@ static int adm1275_probe(struct i2c_client *client) 
			PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |

			PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;



		ret = adm1275_enable_vout_temp(client, config);

		ret = adm1275_enable_vout_temp(data, client, config);

		if (ret)

			return ret;
@@ -694,7 +702,7 @@ static int adm1275_probe(struct i2c_client *client) 
			PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |

			PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;



		ret = adm1275_enable_vout_temp(client, config);

		ret = adm1275_enable_vout_temp(data, client, config);

		if (ret)

			return ret;
@@ -766,8 +774,7 @@ static int adm1275_probe(struct i2c_client *client) 
				"Invalid number of power samples");

			return -EINVAL;

		}

		ret = adm1275_write_pmon_config(data, client, true,

						ilog2(avg));

		ret = adm1275_write_samples(data, client, true, ilog2(avg));

		if (ret < 0) {

			dev_err(&client->dev,

				"Setting power sample averaging failed with error %d",
@@ -784,8 +791,7 @@ static int adm1275_probe(struct i2c_client *client) 
				"Invalid number of voltage/current samples");

			return -EINVAL;

		}

		ret = adm1275_write_pmon_config(data, client, false,

						ilog2(avg));

		ret = adm1275_write_samples(data, client, false, ilog2(avg));

		if (ret < 0) {

			dev_err(&client->dev,

				"Setting voltage and current sample averaging failed with error %d",