diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-hwmon | 9 | ||||
| -rw-r--r-- | Documentation/hwmon/pmbus-core.rst | 9 | ||||
| -rw-r--r-- | drivers/hwmon/pmbus/pmbus_core.c | 89 |
3 files changed, 68 insertions, 39 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-hwmon b/Documentation/ABI/testing/sysfs-class-hwmon index 653d4c75eddb..7271781a23b2 100644 --- a/Documentation/ABI/testing/sysfs-class-hwmon +++ b/Documentation/ABI/testing/sysfs-class-hwmon @@ -938,3 +938,12 @@ Description: - 1: enable RW + +What: /sys/class/hwmon/hwmonX/device/pec +Description: + PEC support on I2C devices + + - 0, off, n: disable + - 1, on, y: enable + + RW diff --git a/Documentation/hwmon/pmbus-core.rst b/Documentation/hwmon/pmbus-core.rst index e7e0c9ef10be..84c5a4e40c40 100644 --- a/Documentation/hwmon/pmbus-core.rst +++ b/Documentation/hwmon/pmbus-core.rst @@ -121,6 +121,15 @@ Specifically, it provides the following information. non-standard PMBus commands to standard commands, or to augment standard command return values with device specific information. +PEC Support +=========== + +Many PMBus devices support SMBus PEC (Packet Error Checking). If supported +by both the I2C adapter and by the PMBus chip, it is by default enabled. +If PEC is supported, the PMBus core driver adds an attribute named 'pec' to +the I2C device. This attribute can be used to control PEC support in the +communication with the PMBus chip. + API functions ============= diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index 02912022853d..e670b868e74b 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -2388,6 +2388,42 @@ static int pmbus_read_status_word(struct i2c_client *client, int page) return _pmbus_read_word_data(client, page, 0xff, PMBUS_STATUS_WORD); } +/* PEC attribute support */ + +static ssize_t pec_show(struct device *dev, struct device_attribute *dummy, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev); + + return sysfs_emit(buf, "%d\n", !!(client->flags & I2C_CLIENT_PEC)); +} + +static ssize_t pec_store(struct device *dev, struct device_attribute *dummy, + const char *buf, size_t count) +{ + struct i2c_client *client = to_i2c_client(dev); + bool enable; + int err; + + err = kstrtobool(buf, &enable); + if (err < 0) + return err; + + if (enable) + client->flags |= I2C_CLIENT_PEC; + else + client->flags &= ~I2C_CLIENT_PEC; + + return count; +} + +static DEVICE_ATTR_RW(pec); + +static void pmbus_remove_pec(void *dev) +{ + device_remove_file(dev, &dev_attr_pec); +} + static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data, struct pmbus_driver_info *info) { @@ -2474,6 +2510,20 @@ static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data, return ret; } + if (client->flags & I2C_CLIENT_PEC) { + /* + * If I2C_CLIENT_PEC is set here, both the I2C adapter and the + * chip support PEC. Add 'pec' attribute to client device to let + * the user control it. + */ + ret = device_create_file(dev, &dev_attr_pec); + if (ret) + return ret; + ret = devm_add_action_or_reset(dev, pmbus_remove_pec, dev); + if (ret) + return ret; + } + return 0; } @@ -2782,42 +2832,6 @@ static int pmbus_debugfs_get_status(void *data, u64 *val) DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops_status, pmbus_debugfs_get_status, NULL, "0x%04llx\n"); -static int pmbus_debugfs_get_pec(void *data, u64 *val) -{ - struct i2c_client *client = data; - - *val = !!(client->flags & I2C_CLIENT_PEC); - - return 0; -} - -static int pmbus_debugfs_set_pec(void *data, u64 val) -{ - int rc; - struct i2c_client *client = data; - - if (!val) { - client->flags &= ~I2C_CLIENT_PEC; - return 0; - } - - if (val != 1) - return -EINVAL; - - rc = i2c_smbus_read_byte_data(client, PMBUS_CAPABILITY); - if (rc < 0) - return rc; - - if (!(rc & PB_CAPABILITY_ERROR_CHECK)) - return -EOPNOTSUPP; - - client->flags |= I2C_CLIENT_PEC; - - return 0; -} -DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops_pec, pmbus_debugfs_get_pec, - pmbus_debugfs_set_pec, "%llu\n"); - static void pmbus_remove_debugfs(void *data) { struct dentry *entry = data; @@ -2853,9 +2867,6 @@ static int pmbus_init_debugfs(struct i2c_client *client, if (!entries) return -ENOMEM; - debugfs_create_file("pec", 0664, data->debugfs, client, - &pmbus_debugfs_ops_pec); - for (i = 0; i < data->info->pages; ++i) { /* Check accessibility of status register if it's not page 0 */ if (!i || pmbus_check_status_register(client, i)) { |