On Thu, Aug 12, 2021 at 01:40:00PM +1200, Chris Packham wrote:
> BPD-RS600 modules running firmware v5.70 misreport the MFR_PIN_MAX.
> The indicate a maximum of 1640W instead of 700W. Detect the invalid
> reading and return a sensible value instead.
>
> Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx>
Applied.
Thanks,
Guenter
> ---
>
> Notes:
> Changes in v2:
> - Add comments for magic values
>
> drivers/hwmon/pmbus/bpa-rs600.c | 23 +++++++++++++++++++++++
> 1 file changed, 23 insertions(+)
>
> diff --git a/drivers/hwmon/pmbus/bpa-rs600.c b/drivers/hwmon/pmbus/bpa-rs600.c
> index 84dee86399cb..f2d4e378a775 100644
> --- a/drivers/hwmon/pmbus/bpa-rs600.c
> +++ b/drivers/hwmon/pmbus/bpa-rs600.c
> @@ -65,6 +65,26 @@ static int bpa_rs600_read_vin(struct i2c_client *client)
> return ret;
> }
>
> +/*
> + * Firmware V5.70 incorrectly reports 1640W for MFR_PIN_MAX.
> + * Deal with this by returning a sensible value.
> + */
> +static int bpa_rs600_read_pin_max(struct i2c_client *client)
> +{
> + int ret;
> +
> + ret = pmbus_read_word_data(client, 0, 0xff, PMBUS_MFR_PIN_MAX);
> + if (ret < 0)
> + return ret;
> +
> + /* Detect invalid 1640W (linear encoding) */
> + if (ret == 0x0b34)
> + /* Report 700W (linear encoding) */
> + return 0x095e;
> +
> + return ret;
> +}
> +
> static int bpa_rs600_read_word_data(struct i2c_client *client, int page, int phase, int reg)
> {
> int ret;
> @@ -91,6 +111,9 @@ static int bpa_rs600_read_word_data(struct i2c_client *client, int page, int pha
> case PMBUS_READ_VIN:
> ret = bpa_rs600_read_vin(client);
> break;
> + case PMBUS_MFR_PIN_MAX:
> + ret = bpa_rs600_read_pin_max(client);
> + break;
> default:
> if (reg >= PMBUS_VIRT_BASE)
> ret = -ENXIO;
