[PATCH v6 1/2] hwmon: (adt7475) Added attenuator bypass support
From: Logan Shaw <hidden>
Date: 2020-01-26 22:10:33
Also in:
linux-hwmon, lkml
Subsystem:
adt7475 hardware monitor driver, hardware monitoring, the rest · Maintainers:
Jean Delvare, Guenter Roeck, Linus Torvalds
Added support for reading DTS properties to set attenuators on device probe for the ADT7473, ADT7475, ADT7476, and ADT7490. Signed-off-by: Logan Shaw <redacted> --- --- drivers/hwmon/adt7475.c | 55 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+)
diff --git a/drivers/hwmon/adt7475.c b/drivers/hwmon/adt7475.c
index 6c64d50c9aae..3f4bdc1eaaec 100644
--- a/drivers/hwmon/adt7475.c
+++ b/drivers/hwmon/adt7475.c@@ -19,6 +19,7 @@ #include <linux/hwmon-vid.h> #include <linux/err.h> #include <linux/jiffies.h> +#include <linux/of.h> #include <linux/util_macros.h> /* Indexes for the sysfs hooks */
@@ -1457,6 +1458,57 @@ static int adt7475_update_limits(struct i2c_client *client) return 0; } +static void modify_config(const struct i2c_client *client, char *property, + u8 *config, u8 bit_index) +{ + u32 prop_value = 0; + int ret = of_property_read_u32(client->dev.of_node, property, + &prop_value); + + if (!ret) { + if (prop_value) + *config |= (1 << bit_index); + else + *config &= ~(1 << bit_index); + } +} + +static int load_attenuators(const struct i2c_client *client, int chip, + u8 *config2, u8 *config4) +{ + u8 conf_copy; + int ret; + + if (chip == adt7476 || chip == adt7490) { + conf_copy = *config4; + + modify_config(client, "bypass-attenuator-in0", &conf_copy, 4); + modify_config(client, "bypass-attenuator-in1", &conf_copy, 5); + modify_config(client, "bypass-attenuator-in3", &conf_copy, 6); + modify_config(client, "bypass-attenuator-in4", &conf_copy, 7); + + ret = i2c_smbus_write_byte_data(client, REG_CONFIG4, + conf_copy); + if (ret < 0) + return ret; + + *config4 = conf_copy; + } else if (chip == adt7473 || chip == adt7475) { + conf_copy = *config2; + + modify_config(client, "bypass-attenuator-in1", &conf_copy, 5); + + ret = i2c_smbus_write_byte_data(client, REG_CONFIG2, + conf_copy); + if (ret < 0) + return ret; + + *config2 = conf_copy; + } + + return 0; +} + static int adt7475_probe(struct i2c_client *client, const struct i2c_device_id *id) {
@@ -1546,6 +1598,9 @@ static int adt7475_probe(struct i2c_client *client, /* Voltage attenuators can be bypassed, globally or individually */ config2 = adt7475_read(REG_CONFIG2); + if (load_attenuators(client, chip, &config2, &data->config4) < 0) + dev_warn(&client->dev, "Error setting bypass attenuators\n"); + if (config2 & CONFIG2_ATTN) { data->bypass_attn = (0x3 << 3) | 0x3; } else {
--
2.25.0