hwmon: Add LTC4245 driver
Add Linux support for the Linear Technology LTC4245 Multiple Supply Hot Swap controller I2C monitoring interface. Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
This commit is contained in:
Ira Snyder
Jean Delvare
parent
2f650631b3
commit
6e34b187bc
81
Documentation/hwmon/ltc4245
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81
Documentation/hwmon/ltc4245
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@ -0,0 +1,81 @@
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Kernel driver ltc4245
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=====================
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Supported chips:
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* Linear Technology LTC4245
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Prefix: 'ltc4245'
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Addresses scanned: 0x20-0x3f
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Datasheet:
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http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
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Author: Ira W. Snyder <iws@ovro.caltech.edu>
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Description
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-----------
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The LTC4245 controller allows a board to be safely inserted and removed
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from a live backplane in multiple supply systems such as CompactPCI and
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PCI Express.
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Usage Notes
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-----------
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This driver does not probe for LTC4245 devices, due to the fact that some
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of the possible addresses are unfriendly to probing. You will need to use
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the "force" parameter to tell the driver where to find the device.
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Example: the following will load the driver for an LTC4245 at address 0x23
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on I2C bus #1:
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$ modprobe ltc4245 force=1,0x23
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Sysfs entries
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-------------
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The LTC4245 has built-in limits for over and under current warnings. This
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makes it very likely that the reference circuit will be used.
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This driver uses the values in the datasheet to change the register values
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into the values specified in the sysfs-interface document. The current readings
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rely on the sense resistors listed in Table 2: "Sense Resistor Values".
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in1_input 12v input voltage (mV)
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in2_input 5v input voltage (mV)
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in3_input 3v input voltage (mV)
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in4_input Vee (-12v) input voltage (mV)
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in1_min_alarm 12v input undervoltage alarm
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in2_min_alarm 5v input undervoltage alarm
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in3_min_alarm 3v input undervoltage alarm
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in4_min_alarm Vee (-12v) input undervoltage alarm
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curr1_input 12v current (mA)
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curr2_input 5v current (mA)
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curr3_input 3v current (mA)
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curr4_input Vee (-12v) current (mA)
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curr1_max_alarm 12v overcurrent alarm
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curr2_max_alarm 5v overcurrent alarm
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curr3_max_alarm 3v overcurrent alarm
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curr4_max_alarm Vee (-12v) overcurrent alarm
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in5_input 12v output voltage (mV)
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in6_input 5v output voltage (mV)
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in7_input 3v output voltage (mV)
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in8_input Vee (-12v) output voltage (mV)
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in5_min_alarm 12v output undervoltage alarm
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in6_min_alarm 5v output undervoltage alarm
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in7_min_alarm 3v output undervoltage alarm
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in8_min_alarm Vee (-12v) output undervoltage alarm
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in9_input GPIO #1 voltage data
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in10_input GPIO #2 voltage data
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in11_input GPIO #3 voltage data
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power1_input 12v power usage (mW)
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power2_input 5v power usage (mW)
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power3_input 3v power usage (mW)
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power4_input Vee (-12v) power usage (mW)
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@ -549,6 +549,17 @@ config SENSORS_LM93
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This driver can also be built as a module. If so, the module
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will be called lm93.
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config SENSORS_LTC4245
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tristate "Linear Technology LTC4245"
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depends on I2C && EXPERIMENTAL
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default n
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help
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If you say yes here you get support for Linear Technology LTC4245
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Multiple Supply Hot Swap Controller I2C interface.
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This driver can also be built as a module. If so, the module will
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be called ltc4245.
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config SENSORS_MAX1111
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tristate "Maxim MAX1111 Multichannel, Serial 8-bit ADC chip"
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depends on SPI_MASTER
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@ -62,6 +62,7 @@ obj-$(CONFIG_SENSORS_LM87) += lm87.o
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obj-$(CONFIG_SENSORS_LM90) += lm90.o
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obj-$(CONFIG_SENSORS_LM92) += lm92.o
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obj-$(CONFIG_SENSORS_LM93) += lm93.o
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obj-$(CONFIG_SENSORS_LTC4245) += ltc4245.o
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obj-$(CONFIG_SENSORS_MAX1111) += max1111.o
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obj-$(CONFIG_SENSORS_MAX1619) += max1619.o
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obj-$(CONFIG_SENSORS_MAX6650) += max6650.o
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567
drivers/hwmon/ltc4245.c
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567
drivers/hwmon/ltc4245.c
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@ -0,0 +1,567 @@
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/*
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* Driver for Linear Technology LTC4245 I2C Multiple Supply Hot Swap Controller
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*
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* Copyright (C) 2008 Ira W. Snyder <iws@ovro.caltech.edu>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This driver is based on the ds1621 and ina209 drivers.
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*
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* Datasheet:
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* http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/err.h>
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#include <linux/slab.h>
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#include <linux/i2c.h>
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#include <linux/hwmon.h>
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#include <linux/hwmon-sysfs.h>
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/* Valid addresses are 0x20 - 0x3f
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*
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* For now, we do not probe, since some of these addresses
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* are known to be unfriendly to probing */
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static const unsigned short normal_i2c[] = { I2C_CLIENT_END };
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/* Insmod parameters */
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I2C_CLIENT_INSMOD_1(ltc4245);
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/* Here are names of the chip's registers (a.k.a. commands) */
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enum ltc4245_cmd {
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LTC4245_STATUS = 0x00, /* readonly */
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LTC4245_ALERT = 0x01,
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LTC4245_CONTROL = 0x02,
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LTC4245_ON = 0x03,
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LTC4245_FAULT1 = 0x04,
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LTC4245_FAULT2 = 0x05,
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LTC4245_GPIO = 0x06,
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LTC4245_ADCADR = 0x07,
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LTC4245_12VIN = 0x10,
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LTC4245_12VSENSE = 0x11,
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LTC4245_12VOUT = 0x12,
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LTC4245_5VIN = 0x13,
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LTC4245_5VSENSE = 0x14,
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LTC4245_5VOUT = 0x15,
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LTC4245_3VIN = 0x16,
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LTC4245_3VSENSE = 0x17,
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LTC4245_3VOUT = 0x18,
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LTC4245_VEEIN = 0x19,
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LTC4245_VEESENSE = 0x1a,
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LTC4245_VEEOUT = 0x1b,
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LTC4245_GPIOADC1 = 0x1c,
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LTC4245_GPIOADC2 = 0x1d,
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LTC4245_GPIOADC3 = 0x1e,
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};
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struct ltc4245_data {
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struct device *hwmon_dev;
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struct mutex update_lock;
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bool valid;
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unsigned long last_updated; /* in jiffies */
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/* Control registers */
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u8 cregs[0x08];
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/* Voltage registers */
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u8 vregs[0x0f];
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};
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static struct ltc4245_data *ltc4245_update_device(struct device *dev)
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{
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struct i2c_client *client = to_i2c_client(dev);
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struct ltc4245_data *data = i2c_get_clientdata(client);
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s32 val;
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int i;
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mutex_lock(&data->update_lock);
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if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
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dev_dbg(&client->dev, "Starting ltc4245 update\n");
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/* Read control registers -- 0x00 to 0x07 */
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for (i = 0; i < ARRAY_SIZE(data->cregs); i++) {
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val = i2c_smbus_read_byte_data(client, i);
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if (unlikely(val < 0))
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data->cregs[i] = 0;
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else
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data->cregs[i] = val;
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}
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/* Read voltage registers -- 0x10 to 0x1f */
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for (i = 0; i < ARRAY_SIZE(data->vregs); i++) {
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val = i2c_smbus_read_byte_data(client, i+0x10);
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if (unlikely(val < 0))
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data->vregs[i] = 0;
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else
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data->vregs[i] = val;
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}
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data->last_updated = jiffies;
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data->valid = 1;
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}
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mutex_unlock(&data->update_lock);
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return data;
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}
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/* Return the voltage from the given register in millivolts */
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static int ltc4245_get_voltage(struct device *dev, u8 reg)
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{
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struct ltc4245_data *data = ltc4245_update_device(dev);
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const u8 regval = data->vregs[reg - 0x10];
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u32 voltage = 0;
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switch (reg) {
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case LTC4245_12VIN:
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case LTC4245_12VOUT:
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voltage = regval * 55;
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break;
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case LTC4245_5VIN:
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case LTC4245_5VOUT:
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voltage = regval * 22;
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break;
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case LTC4245_3VIN:
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case LTC4245_3VOUT:
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voltage = regval * 15;
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break;
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case LTC4245_VEEIN:
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case LTC4245_VEEOUT:
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voltage = regval * -55;
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break;
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case LTC4245_GPIOADC1:
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case LTC4245_GPIOADC2:
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case LTC4245_GPIOADC3:
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voltage = regval * 10;
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break;
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default:
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/* If we get here, the developer messed up */
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WARN_ON_ONCE(1);
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break;
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}
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return voltage;
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}
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/* Return the current in the given sense register in milliAmperes */
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static unsigned int ltc4245_get_current(struct device *dev, u8 reg)
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{
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struct ltc4245_data *data = ltc4245_update_device(dev);
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const u8 regval = data->vregs[reg - 0x10];
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unsigned int voltage;
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unsigned int curr;
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/* The strange looking conversions that follow are fixed-point
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* math, since we cannot do floating point in the kernel.
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*
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* Step 1: convert sense register to microVolts
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* Step 2: convert voltage to milliAmperes
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*
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* If you play around with the V=IR equation, you come up with
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* the following: X uV / Y mOhm == Z mA
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*
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* With the resistors that are fractions of a milliOhm, we multiply
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* the voltage and resistance by 10, to shift the decimal point.
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* Now we can use the normal division operator again.
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*/
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switch (reg) {
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case LTC4245_12VSENSE:
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voltage = regval * 250; /* voltage in uV */
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curr = voltage / 50; /* sense resistor 50 mOhm */
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break;
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case LTC4245_5VSENSE:
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voltage = regval * 125; /* voltage in uV */
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curr = (voltage * 10) / 35; /* sense resistor 3.5 mOhm */
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break;
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case LTC4245_3VSENSE:
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voltage = regval * 125; /* voltage in uV */
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curr = (voltage * 10) / 25; /* sense resistor 2.5 mOhm */
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break;
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case LTC4245_VEESENSE:
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voltage = regval * 250; /* voltage in uV */
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curr = voltage / 100; /* sense resistor 100 mOhm */
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break;
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default:
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/* If we get here, the developer messed up */
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WARN_ON_ONCE(1);
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curr = 0;
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break;
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}
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return curr;
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}
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static ssize_t ltc4245_show_voltage(struct device *dev,
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struct device_attribute *da,
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char *buf)
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{
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struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
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const int voltage = ltc4245_get_voltage(dev, attr->index);
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return snprintf(buf, PAGE_SIZE, "%d\n", voltage);
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}
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static ssize_t ltc4245_show_current(struct device *dev,
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struct device_attribute *da,
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char *buf)
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{
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struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
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const unsigned int curr = ltc4245_get_current(dev, attr->index);
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return snprintf(buf, PAGE_SIZE, "%u\n", curr);
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}
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static ssize_t ltc4245_show_power(struct device *dev,
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struct device_attribute *da,
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char *buf)
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{
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struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
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const unsigned int curr = ltc4245_get_current(dev, attr->index);
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const int output_voltage = ltc4245_get_voltage(dev, attr->index+1);
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/* current in mA * voltage in mV == power in uW */
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const unsigned int power = abs(output_voltage * curr);
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return snprintf(buf, PAGE_SIZE, "%u\n", power);
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}
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static ssize_t ltc4245_show_alarm(struct device *dev,
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struct device_attribute *da,
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char *buf)
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{
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struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
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struct ltc4245_data *data = ltc4245_update_device(dev);
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const u8 reg = data->cregs[attr->index];
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const u32 mask = attr->nr;
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return snprintf(buf, PAGE_SIZE, "%u\n", (reg & mask) ? 1 : 0);
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}
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/* These macros are used below in constructing device attribute objects
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* for use with sysfs_create_group() to make a sysfs device file
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* for each register.
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*/
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#define LTC4245_VOLTAGE(name, ltc4245_cmd_idx) \
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static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
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ltc4245_show_voltage, NULL, ltc4245_cmd_idx)
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#define LTC4245_CURRENT(name, ltc4245_cmd_idx) \
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static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
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ltc4245_show_current, NULL, ltc4245_cmd_idx)
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#define LTC4245_POWER(name, ltc4245_cmd_idx) \
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static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
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ltc4245_show_power, NULL, ltc4245_cmd_idx)
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#define LTC4245_ALARM(name, mask, reg) \
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static SENSOR_DEVICE_ATTR_2(name, S_IRUGO, \
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ltc4245_show_alarm, NULL, (mask), reg)
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/* Construct a sensor_device_attribute structure for each register */
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/* Input voltages */
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LTC4245_VOLTAGE(in1_input, LTC4245_12VIN);
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LTC4245_VOLTAGE(in2_input, LTC4245_5VIN);
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LTC4245_VOLTAGE(in3_input, LTC4245_3VIN);
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LTC4245_VOLTAGE(in4_input, LTC4245_VEEIN);
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/* Input undervoltage alarms */
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LTC4245_ALARM(in1_min_alarm, (1 << 0), LTC4245_FAULT1);
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LTC4245_ALARM(in2_min_alarm, (1 << 1), LTC4245_FAULT1);
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LTC4245_ALARM(in3_min_alarm, (1 << 2), LTC4245_FAULT1);
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LTC4245_ALARM(in4_min_alarm, (1 << 3), LTC4245_FAULT1);
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/* Currents (via sense resistor) */
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LTC4245_CURRENT(curr1_input, LTC4245_12VSENSE);
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LTC4245_CURRENT(curr2_input, LTC4245_5VSENSE);
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LTC4245_CURRENT(curr3_input, LTC4245_3VSENSE);
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LTC4245_CURRENT(curr4_input, LTC4245_VEESENSE);
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/* Overcurrent alarms */
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LTC4245_ALARM(curr1_max_alarm, (1 << 4), LTC4245_FAULT1);
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LTC4245_ALARM(curr2_max_alarm, (1 << 5), LTC4245_FAULT1);
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LTC4245_ALARM(curr3_max_alarm, (1 << 6), LTC4245_FAULT1);
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LTC4245_ALARM(curr4_max_alarm, (1 << 7), LTC4245_FAULT1);
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/* Output voltages */
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LTC4245_VOLTAGE(in5_input, LTC4245_12VOUT);
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LTC4245_VOLTAGE(in6_input, LTC4245_5VOUT);
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LTC4245_VOLTAGE(in7_input, LTC4245_3VOUT);
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LTC4245_VOLTAGE(in8_input, LTC4245_VEEOUT);
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/* Power Bad alarms */
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LTC4245_ALARM(in5_min_alarm, (1 << 0), LTC4245_FAULT2);
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LTC4245_ALARM(in6_min_alarm, (1 << 1), LTC4245_FAULT2);
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LTC4245_ALARM(in7_min_alarm, (1 << 2), LTC4245_FAULT2);
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LTC4245_ALARM(in8_min_alarm, (1 << 3), LTC4245_FAULT2);
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/* GPIO voltages */
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LTC4245_VOLTAGE(in9_input, LTC4245_GPIOADC1);
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LTC4245_VOLTAGE(in10_input, LTC4245_GPIOADC2);
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LTC4245_VOLTAGE(in11_input, LTC4245_GPIOADC3);
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/* Power Consumption (virtual) */
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LTC4245_POWER(power1_input, LTC4245_12VSENSE);
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LTC4245_POWER(power2_input, LTC4245_5VSENSE);
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LTC4245_POWER(power3_input, LTC4245_3VSENSE);
|
||||
LTC4245_POWER(power4_input, LTC4245_VEESENSE);
|
||||
|
||||
/* Finally, construct an array of pointers to members of the above objects,
|
||||
* as required for sysfs_create_group()
|
||||
*/
|
||||
static struct attribute *ltc4245_attributes[] = {
|
||||
&sensor_dev_attr_in1_input.dev_attr.attr,
|
||||
&sensor_dev_attr_in2_input.dev_attr.attr,
|
||||
&sensor_dev_attr_in3_input.dev_attr.attr,
|
||||
&sensor_dev_attr_in4_input.dev_attr.attr,
|
||||
|
||||
&sensor_dev_attr_in1_min_alarm.dev_attr.attr,
|
||||
&sensor_dev_attr_in2_min_alarm.dev_attr.attr,
|
||||
&sensor_dev_attr_in3_min_alarm.dev_attr.attr,
|
||||
&sensor_dev_attr_in4_min_alarm.dev_attr.attr,
|
||||
|
||||
&sensor_dev_attr_curr1_input.dev_attr.attr,
|
||||
&sensor_dev_attr_curr2_input.dev_attr.attr,
|
||||
&sensor_dev_attr_curr3_input.dev_attr.attr,
|
||||
&sensor_dev_attr_curr4_input.dev_attr.attr,
|
||||
|
||||
&sensor_dev_attr_curr1_max_alarm.dev_attr.attr,
|
||||
&sensor_dev_attr_curr2_max_alarm.dev_attr.attr,
|
||||
&sensor_dev_attr_curr3_max_alarm.dev_attr.attr,
|
||||
&sensor_dev_attr_curr4_max_alarm.dev_attr.attr,
|
||||
|
||||
&sensor_dev_attr_in5_input.dev_attr.attr,
|
||||
&sensor_dev_attr_in6_input.dev_attr.attr,
|
||||
&sensor_dev_attr_in7_input.dev_attr.attr,
|
||||
&sensor_dev_attr_in8_input.dev_attr.attr,
|
||||
|
||||
&sensor_dev_attr_in5_min_alarm.dev_attr.attr,
|
||||
&sensor_dev_attr_in6_min_alarm.dev_attr.attr,
|
||||
&sensor_dev_attr_in7_min_alarm.dev_attr.attr,
|
||||
&sensor_dev_attr_in8_min_alarm.dev_attr.attr,
|
||||
|
||||
&sensor_dev_attr_in9_input.dev_attr.attr,
|
||||
&sensor_dev_attr_in10_input.dev_attr.attr,
|
||||
&sensor_dev_attr_in11_input.dev_attr.attr,
|
||||
|
||||
&sensor_dev_attr_power1_input.dev_attr.attr,
|
||||
&sensor_dev_attr_power2_input.dev_attr.attr,
|
||||
&sensor_dev_attr_power3_input.dev_attr.attr,
|
||||
&sensor_dev_attr_power4_input.dev_attr.attr,
|
||||
|
||||
NULL,
|
||||
};
|
||||
|
||||
static const struct attribute_group ltc4245_group = {
|
||||
.attrs = ltc4245_attributes,
|
||||
};
|
||||
|
||||
static int ltc4245_probe(struct i2c_client *client,
|
||||
const struct i2c_device_id *id)
|
||||
{
|
||||
struct ltc4245_data *data;
|
||||
int ret;
|
||||
|
||||
data = kzalloc(sizeof(*data), GFP_KERNEL);
|
||||
if (!data) {
|
||||
ret = -ENOMEM;
|
||||
goto out_kzalloc;
|
||||
}
|
||||
|
||||
i2c_set_clientdata(client, data);
|
||||
mutex_init(&data->update_lock);
|
||||
|
||||
/* Initialize the LTC4245 chip */
|
||||
/* TODO */
|
||||
|
||||
/* Register sysfs hooks */
|
||||
ret = sysfs_create_group(&client->dev.kobj, <c4245_group);
|
||||
if (ret)
|
||||
goto out_sysfs_create_group;
|
||||
|
||||
data->hwmon_dev = hwmon_device_register(&client->dev);
|
||||
if (IS_ERR(data->hwmon_dev)) {
|
||||
ret = PTR_ERR(data->hwmon_dev);
|
||||
goto out_hwmon_device_register;
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
out_hwmon_device_register:
|
||||
sysfs_remove_group(&client->dev.kobj, <c4245_group);
|
||||
out_sysfs_create_group:
|
||||
kfree(data);
|
||||
out_kzalloc:
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int ltc4245_remove(struct i2c_client *client)
|
||||
{
|
||||
struct ltc4245_data *data = i2c_get_clientdata(client);
|
||||
|
||||
hwmon_device_unregister(data->hwmon_dev);
|
||||
sysfs_remove_group(&client->dev.kobj, <c4245_group);
|
||||
|
||||
kfree(data);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Check that some bits in a control register appear at all possible
|
||||
* locations without changing value
|
||||
*
|
||||
* @client: the i2c client to use
|
||||
* @reg: the register to read
|
||||
* @bits: the bits to check (0xff checks all bits,
|
||||
* 0x03 checks only the last two bits)
|
||||
*
|
||||
* return -ERRNO if the register read failed
|
||||
* return -ENODEV if the register value doesn't stay constant at all
|
||||
* possible addresses
|
||||
*
|
||||
* return 0 for success
|
||||
*/
|
||||
static int ltc4245_check_control_reg(struct i2c_client *client, u8 reg, u8 bits)
|
||||
{
|
||||
int i;
|
||||
s32 v, voff1, voff2;
|
||||
|
||||
/* Read register and check for error */
|
||||
v = i2c_smbus_read_byte_data(client, reg);
|
||||
if (v < 0)
|
||||
return v;
|
||||
|
||||
v &= bits;
|
||||
|
||||
for (i = 0x00; i < 0xff; i += 0x20) {
|
||||
|
||||
voff1 = i2c_smbus_read_byte_data(client, reg + i);
|
||||
if (voff1 < 0)
|
||||
return voff1;
|
||||
|
||||
voff2 = i2c_smbus_read_byte_data(client, reg + i + 0x08);
|
||||
if (voff2 < 0)
|
||||
return voff2;
|
||||
|
||||
voff1 &= bits;
|
||||
voff2 &= bits;
|
||||
|
||||
if (v != voff1 || v != voff2)
|
||||
return -ENODEV;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ltc4245_detect(struct i2c_client *client,
|
||||
int kind,
|
||||
struct i2c_board_info *info)
|
||||
{
|
||||
struct i2c_adapter *adapter = client->adapter;
|
||||
|
||||
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
|
||||
return -ENODEV;
|
||||
|
||||
if (kind < 0) { /* probed detection - check the chip type */
|
||||
s32 v; /* 8 bits from the chip, or -ERRNO */
|
||||
|
||||
/* Chip registers 0x00-0x07 are control registers
|
||||
* Chip registers 0x10-0x1f are data registers
|
||||
*
|
||||
* Address bits b7-b5 are ignored. This makes the chip "repeat"
|
||||
* in steps of 0x20. Any control registers should appear with
|
||||
* the same values across all duplicated addresses.
|
||||
*
|
||||
* Register 0x02 bit b2 is reserved, expect 0
|
||||
* Register 0x07 bits b7 to b4 are reserved, expect 0
|
||||
*
|
||||
* Registers 0x01, 0x02 are control registers and should not
|
||||
* change on their own.
|
||||
*
|
||||
* Register 0x06 bits b6 and b7 are control bits, and should
|
||||
* not change on their own.
|
||||
*
|
||||
* Register 0x07 bits b3 to b0 are control bits, and should
|
||||
* not change on their own.
|
||||
*/
|
||||
|
||||
/* read register 0x02 reserved bit, expect 0 */
|
||||
v = i2c_smbus_read_byte_data(client, LTC4245_CONTROL);
|
||||
if (v < 0 || (v & 0x04) != 0)
|
||||
return -ENODEV;
|
||||
|
||||
/* read register 0x07 reserved bits, expect 0 */
|
||||
v = i2c_smbus_read_byte_data(client, LTC4245_ADCADR);
|
||||
if (v < 0 || (v & 0xf0) != 0)
|
||||
return -ENODEV;
|
||||
|
||||
/* check that the alert register appears at all locations */
|
||||
if (ltc4245_check_control_reg(client, LTC4245_ALERT, 0xff))
|
||||
return -ENODEV;
|
||||
|
||||
/* check that the control register appears at all locations */
|
||||
if (ltc4245_check_control_reg(client, LTC4245_CONTROL, 0xff))
|
||||
return -ENODEV;
|
||||
|
||||
/* check that register 0x06 bits b6 and b7 stay constant */
|
||||
if (ltc4245_check_control_reg(client, LTC4245_GPIO, 0xc0))
|
||||
return -ENODEV;
|
||||
|
||||
/* check that register 0x07 bits b3-b0 stay constant */
|
||||
if (ltc4245_check_control_reg(client, LTC4245_ADCADR, 0x0f))
|
||||
return -ENODEV;
|
||||
}
|
||||
|
||||
strlcpy(info->type, "ltc4245", I2C_NAME_SIZE);
|
||||
dev_info(&adapter->dev, "ltc4245 %s at address 0x%02x\n",
|
||||
kind < 0 ? "probed" : "forced",
|
||||
client->addr);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct i2c_device_id ltc4245_id[] = {
|
||||
{ "ltc4245", ltc4245 },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(i2c, ltc4245_id);
|
||||
|
||||
/* This is the driver that will be inserted */
|
||||
static struct i2c_driver ltc4245_driver = {
|
||||
.class = I2C_CLASS_HWMON,
|
||||
.driver = {
|
||||
.name = "ltc4245",
|
||||
},
|
||||
.probe = ltc4245_probe,
|
||||
.remove = ltc4245_remove,
|
||||
.id_table = ltc4245_id,
|
||||
.detect = ltc4245_detect,
|
||||
.address_data = &addr_data,
|
||||
};
|
||||
|
||||
static int __init ltc4245_init(void)
|
||||
{
|
||||
return i2c_add_driver(<c4245_driver);
|
||||
}
|
||||
|
||||
static void __exit ltc4245_exit(void)
|
||||
{
|
||||
i2c_del_driver(<c4245_driver);
|
||||
}
|
||||
|
||||
MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
|
||||
MODULE_DESCRIPTION("LTC4245 driver");
|
||||
MODULE_LICENSE("GPL");
|
||||
|
||||
module_init(ltc4245_init);
|
||||
module_exit(ltc4245_exit);
|
||||
Loading…
Reference in New Issue
Block a user