From dd5219ce4f295a129ee38baff308f9c1e4f0761b Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Wed, 14 Jun 2023 09:36:05 -0700 Subject: [PATCH] hwmon: (pmbus/adm1275) Disable ADC while updating PMON_CONFIG According to ADI, changing PMON_CONFIG while the ADC is running can have unexpected results. ADI recommends halting the ADC with PMON_CONTROL before setting PMON_CONFIG and then resume after. Follow ADI recommendation and disable ADC while PMON_CONFIG is updated. Signed-off-by: Guenter Roeck Link: https://lore.kernel.org/r/20230614163605.3688964-3-linux@roeck-us.net Signed-off-by: Guenter Roeck --- drivers/hwmon/pmbus/adm1275.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/pmbus/adm1275.c b/drivers/hwmon/pmbus/adm1275.c index 84a1b3a..e2c61d6 100644 --- a/drivers/hwmon/pmbus/adm1275.c +++ b/drivers/hwmon/pmbus/adm1275.c @@ -27,8 +27,11 @@ enum chips { adm1075, adm1272, adm1275, adm1276, adm1278, adm1293, adm1294 }; #define ADM1275_PEAK_IOUT 0xd0 #define ADM1275_PEAK_VIN 0xd1 #define ADM1275_PEAK_VOUT 0xd2 +#define ADM1275_PMON_CONTROL 0xd3 #define ADM1275_PMON_CONFIG 0xd4 +#define ADM1275_CONVERT_EN BIT(0) + #define ADM1275_VIN_VOUT_SELECT BIT(6) #define ADM1275_VRANGE BIT(5) #define ADM1075_IRANGE_50 BIT(4) @@ -202,7 +205,11 @@ static int adm1275_read_samples(const struct adm1275_data *data, static int adm1275_write_pmon_config(const struct adm1275_data *data, struct i2c_client *client, u16 word) { - int ret; + int ret, ret2; + + ret = i2c_smbus_write_byte_data(client, ADM1275_PMON_CONTROL, 0); + if (ret) + return ret; if (data->have_power_sampling) ret = i2c_smbus_write_word_data(client, ADM1275_PMON_CONFIG, @@ -211,6 +218,15 @@ static int adm1275_write_pmon_config(const struct adm1275_data *data, ret = i2c_smbus_write_byte_data(client, ADM1275_PMON_CONFIG, word); + /* + * We still want to re-enable conversions if writing into + * ADM1275_PMON_CONFIG failed. + */ + ret2 = i2c_smbus_write_byte_data(client, ADM1275_PMON_CONTROL, + ADM1275_CONVERT_EN); + if (!ret) + ret = ret2; + return ret; } -- 2.7.4