Re: [PATCH] hwmon: (adc128d818) Fix advanced configuration register init
From: Guenter Roeck
Date: Tue Aug 04 2020 - 17:28:20 EST
On Tue, Jul 28, 2020 at 05:18:45PM +0200, Roy van Doormaal wrote:
> If the operation mode is non-zero and an external reference voltage is set,
> first the operation mode is written to the advanced configuration register,
> followed by the externel reference enable bit,
> resetting the configuration mode to 0.
>
> To fix this, first compose the value of the advanced configuration register
> based on the configuration mode and the external reference voltage.
> The advanced configuration register is then written to the device,
> if it is different from the default register value (0x0).
>
> Signed-off-by: Roy van Doormaal <roy.van.doormaal@xxxxxxxxxxxxxxxxxxxxxxxxx>
Applied.
Thanks,
Guenter
> ---
> drivers/hwmon/adc128d818.c | 24 ++++++++++++------------
> 1 file changed, 12 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/hwmon/adc128d818.c b/drivers/hwmon/adc128d818.c
> index f9edec195c35..571d5454c6b2 100644
> --- a/drivers/hwmon/adc128d818.c
> +++ b/drivers/hwmon/adc128d818.c
> @@ -393,6 +393,7 @@ static int adc128_init_client(struct adc128_data *data)
> {
> struct i2c_client *client = data->client;
> int err;
> + u8 regval = 0x0;
>
> /*
> * Reset chip to defaults.
> @@ -403,10 +404,17 @@ static int adc128_init_client(struct adc128_data *data)
> return err;
>
> /* Set operation mode, if non-default */
> - if (data->mode != 0) {
> - err = i2c_smbus_write_byte_data(client,
> - ADC128_REG_CONFIG_ADV,
> - data->mode << 1);
> + if (data->mode != 0)
> + regval |= data->mode << 1;
> +
> + /* If external vref is selected, configure the chip to use it */
> + if (data->regulator)
> + regval |= 0x01;
> +
> + /* Write advanced configuration register */
> + if (regval != 0x0) {
> + err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG_ADV,
> + regval);
> if (err)
> return err;
> }
> @@ -416,14 +424,6 @@ static int adc128_init_client(struct adc128_data *data)
> if (err)
> return err;
>
> - /* If external vref is selected, configure the chip to use it */
> - if (data->regulator) {
> - err = i2c_smbus_write_byte_data(client,
> - ADC128_REG_CONFIG_ADV, 0x01);
> - if (err)
> - return err;
> - }
> -
> return 0;
> }
>