[PATCH v5 1/5] hwmon: (pmbus/pim4328) Add new pmbus flag NO_WRITE_PROTECT
From: Erik Rosen <hidden>
Date: 2021-06-09 10:50:10
Also in:
linux-hwmon, lkml
Subsystem:
hardware monitoring, the rest · Maintainers:
Guenter Roeck, Linus Torvalds
Some PMBus chips respond with invalid data when reading the WRITE_PROTECT register. For such chips, this flag should be set so that the PMBus core driver doesn't use the WRITE_PROTECT command to determine its behavior. Signed-off-by: Erik Rosen <redacted> --- drivers/hwmon/pmbus/pmbus_core.c | 8 +++++--- include/linux/pmbus.h | 9 +++++++++ 2 files changed, 14 insertions(+), 3 deletions(-)
diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index bbd745178147..0579521b6c0a 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c@@ -2226,9 +2226,11 @@ static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data, * faults, and we should not try it. Also, in that case, writes into * limit registers need to be disabled. */ - ret = i2c_smbus_read_byte_data(client, PMBUS_WRITE_PROTECT); - if (ret > 0 && (ret & PB_WP_ANY)) - data->flags |= PMBUS_WRITE_PROTECTED | PMBUS_SKIP_STATUS_CHECK; + if (!(data->flags & PMBUS_NO_WRITE_PROTECT)) { + ret = i2c_smbus_read_byte_data(client, PMBUS_WRITE_PROTECT); + if (ret > 0 && (ret & PB_WP_ANY)) + data->flags |= PMBUS_WRITE_PROTECTED | PMBUS_SKIP_STATUS_CHECK; + } if (data->info->pages) pmbus_clear_faults(client);
diff --git a/include/linux/pmbus.h b/include/linux/pmbus.h
index 12cbbf305969..86bacf57f8e9 100644
--- a/include/linux/pmbus.h
+++ b/include/linux/pmbus.h@@ -43,6 +43,15 @@ */ #define PMBUS_NO_CAPABILITY BIT(2) +/* + * PMBUS_NO_WRITE_PROTECT + * + * Some PMBus chips respond with invalid data when reading the WRITE_PROTECT + * register. For such chips, this flag should be set so that the PMBus core + * driver doesn't use the WRITE_PROTECT command to determine its behavior. + */ +#define PMBUS_NO_WRITE_PROTECT BIT(4) + struct pmbus_platform_data { u32 flags; /* Device specific flags */
--
2.20.1