From 1125bacbf36cc53121cecba20d1def032881085d Mon Sep 17 00:00:00 2001 From: Chris Packham Date: Thu, 12 Aug 2021 13:40:00 +1200 Subject: hwmon: (pmbus/bpa-rs600) Add workaround for incorrect Pin max 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 Link: https://lore.kernel.org/r/20210812014000.26293-3-chris.packham@alliedtelesis.co.nz Signed-off-by: Guenter Roeck --- drivers/hwmon/pmbus/bpa-rs600.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'drivers/hwmon/pmbus') 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; -- cgit v1.2.3