Re: [PATCH] adm1275: support PMBUS_VIRT_*_SAMPLES

Sverdlin, Alexander (Nokia - DE/Ulm)
2019-05-24T13:02:31Z

Hi!

On 24/05/2019 14:49, Adamski, Krzysztof (Nokia - PL/Wroclaw) wrote:
> The device supports setting the number of samples for averaging the
> measurements. There are two separate settings - PWR_AVG for averaging
> PIN and VI_AVG for averaging VIN/VAUX/IOUT, both being part of
> PMON_CONFIG register. The values are stored as exponent of base 2 of the
> actual number of samples that will be taken.
>
> Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>

Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>

> ---
> drivers/hwmon/pmbus/adm1275.c | 68 ++++++++++++++++++++++++++++++++++-
> 1 file changed, 67 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hwmon/pmbus/adm1275.c b/drivers/hwmon/pmbus/adm1275.c
> index f569372c9204..4efe1a9df563 100644
> --- a/drivers/hwmon/pmbus/adm1275.c
> +++ b/drivers/hwmon/pmbus/adm1275.c
> @@ -23,6 +23,8 @@
> #include <linux/slab.h>
> #include <linux/i2c.h>
> #include <linux/bitops.h>
> +#include <linux/bitfield.h>
> +#include <linux/log2.h>
> #include "pmbus.h"
>
> enum chips { adm1075, adm1272, adm1275, adm1276, adm1278, adm1293, adm1294 };
> @@ -78,6 +80,10 @@ enum chips { adm1075, adm1272, adm1275, adm1276, adm1278, adm1293, adm1294 };
> #define ADM1075_VAUX_OV_WARN BIT(7)
> #define ADM1075_VAUX_UV_WARN BIT(6)
>
> +#define ADM1275_PWR_AVG_MASK GENMASK(13, 11)
> +#define ADM1275_VI_AVG_MASK GENMASK(10, 8)
> +#define ADM1275_SAMPLES_AVG_MAX 128
> +
> struct adm1275_data {
> int id;
> bool have_oc_fault;
> @@ -90,6 +96,7 @@ struct adm1275_data {
> bool have_pin_max;
> bool have_temp_max;
> struct pmbus_driver_info info;
> + struct mutex lock;
> };
>
> #define to_adm1275_data(x) container_of(x, struct adm1275_data, info)
> @@ -164,6 +171,38 @@ static const struct coefficients adm1293_coefficients[] = {
> [18] = { 7658, 0, -3 }, /* power, 21V, irange200 */
> };
>
> +static inline int adm1275_read_pmon_config(struct i2c_client *client, u64 mask)
> +{
> + int ret;
> +
> + ret = i2c_smbus_read_word_data(client, ADM1275_PMON_CONFIG);
> + if (ret < 0)
> + return ret;
> +
> + return FIELD_GET(mask, ret);
> +}
> +
> +static inline int adm1275_write_pmon_config(struct i2c_client *client, u64 mask,
> + u16 word)
> +{
> + const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
> + struct adm1275_data *data = to_adm1275_data(info);
> + int ret;
> +
> + mutex_lock(&data->lock);
> + ret = i2c_smbus_read_word_data(client, ADM1275_PMON_CONFIG);
> + if (ret < 0) {
> + mutex_unlock(&data->lock);
> + return ret;
> + }
> +
> + word = FIELD_PREP(mask, word) | (ret & ~mask);
> + ret = i2c_smbus_write_word_data(client, ADM1275_PMON_CONFIG, word);
> + mutex_unlock(&data->lock);
> +
> + return ret;
> +}
> +
> static int adm1275_read_word_data(struct i2c_client *client, int page, int reg)
> {
> const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
> @@ -242,6 +281,19 @@ static int adm1275_read_word_data(struct i2c_client *client, int page, int reg)
> if (!data->have_temp_max)
> return -ENXIO;
> break;
> + case PMBUS_VIRT_POWER_SAMPLES:
> + ret = adm1275_read_pmon_config(client, ADM1275_PWR_AVG_MASK);
> + if (ret < 0)
> + break;
> + ret = 1 << ret;
> + break;
> + case PMBUS_VIRT_IN_SAMPLES:
> + case PMBUS_VIRT_CURR_SAMPLES:
> + ret = adm1275_read_pmon_config(client, ADM1275_VI_AVG_MASK);
> + if (ret < 0)
> + break;
> + ret = 1 << ret;
> + break;
> default:
> ret = -ENODATA;
> break;
> @@ -286,6 +338,17 @@ static int adm1275_write_word_data(struct i2c_client *client, int page, int reg,
> case PMBUS_VIRT_RESET_TEMP_HISTORY:
> ret = pmbus_write_word_data(client, 0, ADM1278_PEAK_TEMP, 0);
> break;
> + case PMBUS_VIRT_POWER_SAMPLES:
> + word = clamp_val(word, 1, ADM1275_SAMPLES_AVG_MAX);
> + ret = adm1275_write_pmon_config(client, ADM1275_PWR_AVG_MASK,
> + 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(client, ADM1275_VI_AVG_MASK,
> + ilog2(word));
> + break;
> default:
> ret = -ENODATA;
> break;
> @@ -422,6 +485,8 @@ static int adm1275_probe(struct i2c_client *client,
> if (!data)
> return -ENOMEM;
>
> + mutex_init(&data->lock);
> +
> if (of_property_read_u32(client->dev.of_node,
> "shunt-resistor-micro-ohms", &shunt))
> shunt = 1000; /* 1 mOhm if not set via DT */
> @@ -439,7 +504,8 @@ static int adm1275_probe(struct i2c_client *client,
> info->format[PSC_CURRENT_OUT] = direct;
> info->format[PSC_POWER] = direct;
> info->format[PSC_TEMPERATURE] = direct;
> - info->func[0] = PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
> + info->func[0] = PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
> + PMBUS_HAVE_SAMPLES;
>
> info->read_word_data = adm1275_read_word_data;
> info->read_byte_data = adm1275_read_byte_data;

--
Best regards,
Alexander Sverdlin.