From e5befc024cb4515d815662ed8746712cc5366bfc Mon Sep 17 00:00:00 2001 From: Eddie James Date: Tue, 22 Dec 2020 09:26:39 -0600 Subject: [PATCH] hwmon: (pmbus) Add a PMBUS_NO_CAPABILITY platform data flag Some PMBus chips don't respond with valid data when reading the CAPABILITY register. Add a flag that device drivers can set so that the PMBus core driver doesn't use CAPABILITY to determine it's behavior. Signed-off-by: Eddie James Link: https://lore.kernel.org/r/20201222152640.27749-2-eajames@linux.ibm.com Signed-off-by: Guenter Roeck --- 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 192442b..906c9fe 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -2204,9 +2204,11 @@ static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data, } /* Enable PEC if the controller supports it */ - ret = i2c_smbus_read_byte_data(client, PMBUS_CAPABILITY); - if (ret >= 0 && (ret & PB_CAPABILITY_ERROR_CHECK)) - client->flags |= I2C_CLIENT_PEC; + if (!(data->flags & PMBUS_NO_CAPABILITY)) { + ret = i2c_smbus_read_byte_data(client, PMBUS_CAPABILITY); + if (ret >= 0 && (ret & PB_CAPABILITY_ERROR_CHECK)) + client->flags |= I2C_CLIENT_PEC; + } /* * Check if the chip is write protected. If it is, we can not clear diff --git a/include/linux/pmbus.h b/include/linux/pmbus.h index 1ea5bae..12cbbf3 100644 --- a/include/linux/pmbus.h +++ b/include/linux/pmbus.h @@ -34,6 +34,15 @@ */ #define PMBUS_WRITE_PROTECTED BIT(1) +/* + * PMBUS_NO_CAPABILITY + * + * Some PMBus chips don't respond with valid data when reading the CAPABILITY + * register. For such chips, this flag should be set so that the PMBus core + * driver doesn't use CAPABILITY to determine it's behavior. + */ +#define PMBUS_NO_CAPABILITY BIT(2) + struct pmbus_platform_data { u32 flags; /* Device specific flags */ -- 2.7.4