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>
---
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;
--
2.32.0
