* [lm-sensors] [PATCH] hwmon: Add LTC4245 driver
@ 2008-10-20 16:03 Ira Snyder
2008-10-20 17:29 ` Hans de Goede
` (7 more replies)
0 siblings, 8 replies; 9+ messages in thread
From: Ira Snyder @ 2008-10-20 16:03 UTC (permalink / raw)
To: lm-sensors
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>
---
I'm pretty sure this should be the final revision of the driver. Please
go ahead and forward it upstream. :)
I apologize for the late response. I was having some troubles with my
email. They should all be sorted out now.
Thanks for all the help and review!
Ira
Changes v3 -> v4:
* simplify ltc4245_get_voltage(), removing special casing for -12v
* power should always be a positive value
Changes v2 -> v3:
* fix units (power?_input in uW, curr?_input in mA)
* combine all alarm functions
* rename power[1-4]_alarm to in[5-8]_min_alarm, per suggestions
Changes v1 -> v2:
* fixed checkpatch warnings
* removed raw register access, per suggestions
* changed sysfs interface, per suggestions (current, power, alarms)
Documentation/hwmon/ltc4245 | 69 +++++
drivers/hwmon/Kconfig | 11 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/ltc4245.c | 574 +++++++++++++++++++++++++++++++++++++++++++
4 files changed, 655 insertions(+), 0 deletions(-)
create mode 100644 Documentation/hwmon/ltc4245
create mode 100644 drivers/hwmon/ltc4245.c
diff --git a/Documentation/hwmon/ltc4245 b/Documentation/hwmon/ltc4245
new file mode 100644
index 0000000..d2f411a
--- /dev/null
+++ b/Documentation/hwmon/ltc4245
@@ -0,0 +1,69 @@
+Kernel driver ltc4245
+==========+
+Supported chips:
+ * Linear Technology LTC4245
+ Prefix: 'ltc4245'
+ Addresses scanned: 0x20-0x3f
+ Datasheet:
+ http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
+
+Author: Ira W. Snyder <iws@ovro.caltech.edu>
+
+
+Description
+-----------
+
+The LTC4245 controller allows a board to be safely inserted and removed
+from a live backplane in multiple supply systems such as CompactPCI and
+PCI Express.
+
+
+Sysfs entries
+-------------
+
+The LTC4245 has built-in limits for over and under current warnings. This
+makes it very likely that the reference circuit will be used.
+
+This driver uses the values in the datasheet to change the register values
+into the values specified in the sysfs-interface document. The current readings
+rely on the sense resistors listed in Table 2: "Sense Resistor Values".
+
+in1_input 12v input voltage (mV)
+in2_input 5v input voltage (mV)
+in3_input 3v input voltage (mV)
+in4_input Vee (-12v) input voltage (mV)
+
+in1_min_alarm 12v input undervoltage alarm
+in2_min_alarm 5v input undervoltage alarm
+in3_min_alarm 3v input undervoltage alarm
+in4_min_alarm Vee (-12v) input undervoltage alarm
+
+curr1_input 12v current (mA)
+curr2_input 5v current (mA)
+curr3_input 3v current (mA)
+curr4_input Vee (-12v) current (mA)
+
+curr1_max_alarm 12v overcurrent alarm
+curr2_max_alarm 5v overcurrent alarm
+curr3_max_alarm 3v overcurrent alarm
+curr4_max_alarm Vee (-12v) overcurrent alarm
+
+in5_input 12v output voltage (mV)
+in6_input 5v output voltage (mV)
+in7_input 3v output voltage (mV)
+in8_input Vee (-12v) output voltage (mV)
+
+in5_min_alarm 12v output undervoltage alarm
+in6_min_alarm 5v output undervoltage alarm
+in7_min_alarm 3v output undervoltage alarm
+in8_min_alarm Vee (-12v) output undervoltage alarm
+
+in9_input GPIO #1 voltage data
+in10_input GPIO #2 voltage data
+in11_input GPIO #3 voltage data
+
+power1_input 12v power usage (mW)
+power2_input 5v power usage (mW)
+power3_input 3v power usage (mW)
+power4_input Vee (-12v) power usage (mW)
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index d402e8d..91bec8a 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -836,6 +836,17 @@ config SENSORS_APPLESMC
Say Y here if you have an applicable laptop and want to experience
the awesome power of applesmc.
+config SENSORS_LTC4245
+ tristate "Linear Technology LTC4245"
+ depends on I2C && EXPERIMENTAL
+ default n
+ help
+ If you say yes here you get support for Linear Technology LTC4245
+ Multiple Supply Hot Swap Controller I2C interface.
+
+ This driver can also be built as a module. If so, the module will
+ be called ltc4245.
+
config HWMON_DEBUG_CHIP
bool "Hardware Monitoring Chip debugging messages"
default n
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 950134a..0ed56ac 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -59,6 +59,7 @@ obj-$(CONFIG_SENSORS_LM87) += lm87.o
obj-$(CONFIG_SENSORS_LM90) += lm90.o
obj-$(CONFIG_SENSORS_LM92) += lm92.o
obj-$(CONFIG_SENSORS_LM93) += lm93.o
+obj-$(CONFIG_SENSORS_LTC4245) += ltc4245.o
obj-$(CONFIG_SENSORS_MAX1619) += max1619.o
obj-$(CONFIG_SENSORS_MAX6650) += max6650.o
obj-$(CONFIG_SENSORS_PC87360) += pc87360.o
diff --git a/drivers/hwmon/ltc4245.c b/drivers/hwmon/ltc4245.c
new file mode 100644
index 0000000..5d0528b
--- /dev/null
+++ b/drivers/hwmon/ltc4245.c
@@ -0,0 +1,574 @@
+/*
+ * Driver for Linear Technology LTC4245 I2C Multiple Supply Hot Swap Controller
+ *
+ * Copyright (C) 2008 Ira W. Snyder <iws@ovro.caltech.edu>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This driver is based on the ds1621 and ina209 drivers.
+ *
+ * Datasheet:
+ * http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+/* Addresses to probe */
+static unsigned short normal_i2c[] = {
+ 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
+ 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
+ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
+ 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
+ I2C_CLIENT_END};
+
+/* Insmod parameters */
+I2C_CLIENT_INSMOD_1(ltc4245);
+
+/* Here are names of the chip's registers (a.k.a. commands) */
+enum ltc4245_cmd {
+ LTC4245_STATUS = 0x00, /* readonly */
+ LTC4245_ALERT = 0x01,
+ LTC4245_CONTROL = 0x02,
+ LTC4245_ON = 0x03,
+ LTC4245_FAULT1 = 0x04,
+ LTC4245_FAULT2 = 0x05,
+ LTC4245_GPIO = 0x06,
+ LTC4245_ADCADR = 0x07,
+
+ LTC4245_12VIN = 0x10,
+ LTC4245_12VSENSE = 0x11,
+ LTC4245_12VOUT = 0x12,
+ LTC4245_5VIN = 0x13,
+ LTC4245_5VSENSE = 0x14,
+ LTC4245_5VOUT = 0x15,
+ LTC4245_3VIN = 0x16,
+ LTC4245_3VSENSE = 0x17,
+ LTC4245_3VOUT = 0x18,
+ LTC4245_VEEIN = 0x19,
+ LTC4245_VEESENSE = 0x1a,
+ LTC4245_VEEOUT = 0x1b,
+ LTC4245_GPIOADC1 = 0x1c,
+ LTC4245_GPIOADC2 = 0x1d,
+ LTC4245_GPIOADC3 = 0x1e,
+};
+
+struct ltc4245_data {
+ struct device *hwmon_dev;
+
+ struct mutex update_lock;
+ bool valid;
+ unsigned long last_updated; /* in jiffies */
+
+ /* Control registers */
+ u8 cregs[0x08];
+
+ /* Voltage registers */
+ u8 vregs[0x0f];
+};
+
+/* All registers are byte-sized (8 bit) */
+static s32 ltc4245_read_reg(struct i2c_client *client, u8 reg)
+{
+ return i2c_smbus_read_byte_data(client, reg);
+}
+
+#if 0
+static s32 ltc4245_write_reg(struct i2c_client *client, u8 reg, u8 val)
+{
+ return i2c_smbus_write_byte_data(client, reg, val);
+}
+#endif
+
+static struct ltc4245_data *ltc4245_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ltc4245_data *data = i2c_get_clientdata(client);
+ int i;
+
+ mutex_lock(&data->update_lock);
+
+ if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+
+ dev_dbg(&client->dev, "Starting ltc4245 update\n");
+
+ /* Read control registers -- 0x00 to 0x07 */
+ for (i = 0; i < ARRAY_SIZE(data->cregs); i++)
+ data->cregs[i] = ltc4245_read_reg(client, i);
+
+ /* Read voltage registers -- 0x10 to 0x1f */
+ for (i = 0; i < ARRAY_SIZE(data->vregs); i++)
+ data->vregs[i] = ltc4245_read_reg(client, i+0x10);
+
+ data->last_updated = jiffies;
+ data->valid = 1;
+ }
+
+ mutex_unlock(&data->update_lock);
+
+ return data;
+}
+
+/* Return the voltage from the given register in millivolts */
+static int ltc4245_get_voltage(struct device *dev, u8 reg)
+{
+ struct ltc4245_data *data = ltc4245_update_device(dev);
+ const s32 val = data->vregs[reg - 0x10];
+ const u8 regval = val;
+ u32 voltage = 0;
+
+ if (unlikely(val < 0))
+ return 0;
+
+ switch (reg) {
+ case LTC4245_12VIN:
+ case LTC4245_12VOUT:
+ voltage = regval * 55;
+ break;
+ case LTC4245_5VIN:
+ case LTC4245_5VOUT:
+ voltage = regval * 22;
+ break;
+ case LTC4245_3VIN:
+ case LTC4245_3VOUT:
+ voltage = regval * 15;
+ break;
+ case LTC4245_VEEIN:
+ case LTC4245_VEEOUT:
+ voltage = regval * -55;
+ break;
+ case LTC4245_GPIOADC1:
+ case LTC4245_GPIOADC2:
+ case LTC4245_GPIOADC3:
+ voltage = regval * 10;
+ break;
+ default:
+ /* If we get here, the developer messed up */
+ WARN_ON_ONCE(1);
+ break;
+ }
+
+ return voltage;
+}
+
+/* Return the current in the given sense register in milliAmperes */
+static u32 ltc4245_get_current(struct device *dev, u8 reg)
+{
+ struct ltc4245_data *data = ltc4245_update_device(dev);
+ const s32 val = data->vregs[reg - 0x10];
+ const u8 regval = val;
+ u32 voltage;
+ u32 current;
+
+ if (unlikely(val) < 0)
+ return 0;
+
+ /* The strange looking conversions that follow are fixed-point
+ * math, since we cannot do floating point in the kernel.
+ *
+ * Step 1: convert sense register to microVolts
+ * Step 2: convert voltage to milliAmperes
+ *
+ * If you play around with the V=IR equation, you come up with
+ * the following: X uV / Y mOhm = Z mA
+ *
+ * With the resistors that are fractions of a milliOhm, we multiply
+ * the voltage and resistance by 10, to shift the decimal point.
+ * Now we can use the normal division operator again.
+ */
+
+ switch (reg) {
+ case LTC4245_12VSENSE:
+ voltage = regval * 250; /* voltage in uV */
+ current = voltage / 50; /* sense resistor 50 mOhm */
+ break;
+ case LTC4245_5VSENSE:
+ voltage = regval * 125; /* voltage in uV */
+ current = (voltage * 10) / 35; /* sense resistor 3.5 mOhm */
+ break;
+ case LTC4245_3VSENSE:
+ voltage = regval * 125; /* voltage in uV */
+ current = (voltage * 10) / 25; /* sense resistor 2.5 mOhm */
+ break;
+ case LTC4245_VEESENSE:
+ voltage = regval * 250; /* voltage in uV */
+ current = voltage / 100; /* sense resistor 100 mOhm */
+ break;
+ default:
+ /* If we get here, the developer messed up */
+ WARN_ON_ONCE(1);
+ current = 0;
+ break;
+ }
+
+ return current;
+}
+
+static ssize_t ltc4245_show_voltage(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const u32 voltage = ltc4245_get_voltage(dev, attr->index);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", voltage);
+}
+
+static ssize_t ltc4245_show_current(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const u32 current = ltc4245_get_current(dev, attr->index);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", current);
+}
+
+static ssize_t ltc4245_show_power(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const u32 current = ltc4245_get_current(dev, attr->index);
+ const u32 output_voltage = ltc4245_get_voltage(dev, attr->index+1);
+
+ /* current in mA * voltage in mV = power in uW */
+ const unsigned int power = abs(output_voltage * current);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", power);
+}
+
+static ssize_t ltc4245_show_alarm(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
+ struct ltc4245_data *data = ltc4245_update_device(dev);
+ const s32 reg = data->cregs[attr->index];
+ const u32 mask = attr->nr;
+
+ if (unlikely(reg < 0)) {
+ memset(buf, 0, PAGE_SIZE); /* user should not see old data */
+ return 0;
+ }
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", (reg & mask) ? 1 : 0);
+}
+
+/* These macros are used below in constructing device attribute objects
+ * for use with sysfs_create_group() to make a sysfs device file
+ * for each register.
+ */
+
+#define LTC4245_VOLTAGE(name, ltc4245_cmd_idx) \
+ static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+ ltc4245_show_voltage, NULL, ltc4245_cmd_idx)
+
+#define LTC4245_CURRENT(name, ltc4245_cmd_idx) \
+ static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+ ltc4245_show_current, NULL, ltc4245_cmd_idx)
+
+#define LTC4245_POWER(name, ltc4245_cmd_idx) \
+ static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+ ltc4245_show_power, NULL, ltc4245_cmd_idx)
+
+#define LTC4245_ALARM(name, mask, reg) \
+ static SENSOR_DEVICE_ATTR_2(name, S_IRUGO, \
+ ltc4245_show_alarm, NULL, (mask), reg)
+
+/* Construct a sensor_device_attribute structure for each register */
+
+/* Input voltages */
+LTC4245_VOLTAGE(in1_input, LTC4245_12VIN);
+LTC4245_VOLTAGE(in2_input, LTC4245_5VIN);
+LTC4245_VOLTAGE(in3_input, LTC4245_3VIN);
+LTC4245_VOLTAGE(in4_input, LTC4245_VEEIN);
+
+/* Input undervoltage alarms */
+LTC4245_ALARM(in1_min_alarm, (1 << 0), LTC4245_FAULT1);
+LTC4245_ALARM(in2_min_alarm, (1 << 1), LTC4245_FAULT1);
+LTC4245_ALARM(in3_min_alarm, (1 << 2), LTC4245_FAULT1);
+LTC4245_ALARM(in4_min_alarm, (1 << 3), LTC4245_FAULT1);
+
+/* Currents (via sense resistor) */
+LTC4245_CURRENT(curr1_input, LTC4245_12VSENSE);
+LTC4245_CURRENT(curr2_input, LTC4245_5VSENSE);
+LTC4245_CURRENT(curr3_input, LTC4245_3VSENSE);
+LTC4245_CURRENT(curr4_input, LTC4245_VEESENSE);
+
+/* Overcurrent alarms */
+LTC4245_ALARM(curr1_max_alarm, (1 << 4), LTC4245_FAULT1);
+LTC4245_ALARM(curr2_max_alarm, (1 << 5), LTC4245_FAULT1);
+LTC4245_ALARM(curr3_max_alarm, (1 << 6), LTC4245_FAULT1);
+LTC4245_ALARM(curr4_max_alarm, (1 << 7), LTC4245_FAULT1);
+
+/* Output voltages */
+LTC4245_VOLTAGE(in5_input, LTC4245_12VOUT);
+LTC4245_VOLTAGE(in6_input, LTC4245_5VOUT);
+LTC4245_VOLTAGE(in7_input, LTC4245_3VOUT);
+LTC4245_VOLTAGE(in8_input, LTC4245_VEEOUT);
+
+/* Power Bad alarms */
+LTC4245_ALARM(in5_min_alarm, (1 << 0), LTC4245_FAULT2);
+LTC4245_ALARM(in6_min_alarm, (1 << 1), LTC4245_FAULT2);
+LTC4245_ALARM(in7_min_alarm, (1 << 2), LTC4245_FAULT2);
+LTC4245_ALARM(in8_min_alarm, (1 << 3), LTC4245_FAULT2);
+
+/* GPIO voltages */
+LTC4245_VOLTAGE(in9_input, LTC4245_GPIOADC1);
+LTC4245_VOLTAGE(in10_input, LTC4245_GPIOADC2);
+LTC4245_VOLTAGE(in11_input, LTC4245_GPIOADC3);
+
+/* Power Consumption (virtual) */
+LTC4245_POWER(power1_input, LTC4245_12VSENSE);
+LTC4245_POWER(power2_input, LTC4245_5VSENSE);
+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 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 -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;
+
+ v = ltc4245_read_reg(client, reg) & bits;
+
+ if (v < 0)
+ return -ENODEV;
+
+ for (i = 0x00; i < 0xff; i += 0x20) {
+ voff1 = ltc4245_read_reg(client, reg + i) & bits;
+ voff2 = ltc4245_read_reg(client, reg + i + 0x08) & bits;
+
+ if (voff1 < 0 || voff2 < 0 || 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 = ltc4245_read_reg(client, LTC4245_CONTROL);
+ if (v < 0 || (v & 0x04) != 0)
+ return -ENODEV;
+
+ /* read register 0x07 reserved bits, expect 0 */
+ v = ltc4245_read_reg(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);
+ pr_info("ltc4245: %s on i2c-%u address 0x%02x\n",
+ kind < 0 ? "probed" : "forced",
+ adapter->nr, 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);
--
1.5.4.3
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [lm-sensors] [PATCH] hwmon: Add LTC4245 driver
2008-10-20 16:03 [lm-sensors] [PATCH] hwmon: Add LTC4245 driver Ira Snyder
@ 2008-10-20 17:29 ` Hans de Goede
2008-10-21 12:19 ` Jean Delvare
` (6 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Hans de Goede @ 2008-10-20 17:29 UTC (permalink / raw)
To: lm-sensors
Ira Snyder wrote:
> 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>
> ---
>
> I'm pretty sure this should be the final revision of the driver. Please
> go ahead and forward it upstream. :)
>
Looks good now :)
Jean, can you put this patch in your for Linus for 2.6.28 queue please?
This is:
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
or
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Whatever you deem more appropriate.
Thanks & Regards,
Hans
> Changes v3 -> v4:
> * simplify ltc4245_get_voltage(), removing special casing for -12v
> * power should always be a positive value
>
> Changes v2 -> v3:
> * fix units (power?_input in uW, curr?_input in mA)
> * combine all alarm functions
> * rename power[1-4]_alarm to in[5-8]_min_alarm, per suggestions
>
> Changes v1 -> v2:
> * fixed checkpatch warnings
> * removed raw register access, per suggestions
> * changed sysfs interface, per suggestions (current, power, alarms)
>
>
> Documentation/hwmon/ltc4245 | 69 +++++
> drivers/hwmon/Kconfig | 11 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/ltc4245.c | 574 +++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 655 insertions(+), 0 deletions(-)
> create mode 100644 Documentation/hwmon/ltc4245
> create mode 100644 drivers/hwmon/ltc4245.c
>
> diff --git a/Documentation/hwmon/ltc4245 b/Documentation/hwmon/ltc4245
> new file mode 100644
> index 0000000..d2f411a
> --- /dev/null
> +++ b/Documentation/hwmon/ltc4245
> @@ -0,0 +1,69 @@
> +Kernel driver ltc4245
> +==========> +
> +Supported chips:
> + * Linear Technology LTC4245
> + Prefix: 'ltc4245'
> + Addresses scanned: 0x20-0x3f
> + Datasheet:
> + http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
> +
> +Author: Ira W. Snyder <iws@ovro.caltech.edu>
> +
> +
> +Description
> +-----------
> +
> +The LTC4245 controller allows a board to be safely inserted and removed
> +from a live backplane in multiple supply systems such as CompactPCI and
> +PCI Express.
> +
> +
> +Sysfs entries
> +-------------
> +
> +The LTC4245 has built-in limits for over and under current warnings. This
> +makes it very likely that the reference circuit will be used.
> +
> +This driver uses the values in the datasheet to change the register values
> +into the values specified in the sysfs-interface document. The current readings
> +rely on the sense resistors listed in Table 2: "Sense Resistor Values".
> +
> +in1_input 12v input voltage (mV)
> +in2_input 5v input voltage (mV)
> +in3_input 3v input voltage (mV)
> +in4_input Vee (-12v) input voltage (mV)
> +
> +in1_min_alarm 12v input undervoltage alarm
> +in2_min_alarm 5v input undervoltage alarm
> +in3_min_alarm 3v input undervoltage alarm
> +in4_min_alarm Vee (-12v) input undervoltage alarm
> +
> +curr1_input 12v current (mA)
> +curr2_input 5v current (mA)
> +curr3_input 3v current (mA)
> +curr4_input Vee (-12v) current (mA)
> +
> +curr1_max_alarm 12v overcurrent alarm
> +curr2_max_alarm 5v overcurrent alarm
> +curr3_max_alarm 3v overcurrent alarm
> +curr4_max_alarm Vee (-12v) overcurrent alarm
> +
> +in5_input 12v output voltage (mV)
> +in6_input 5v output voltage (mV)
> +in7_input 3v output voltage (mV)
> +in8_input Vee (-12v) output voltage (mV)
> +
> +in5_min_alarm 12v output undervoltage alarm
> +in6_min_alarm 5v output undervoltage alarm
> +in7_min_alarm 3v output undervoltage alarm
> +in8_min_alarm Vee (-12v) output undervoltage alarm
> +
> +in9_input GPIO #1 voltage data
> +in10_input GPIO #2 voltage data
> +in11_input GPIO #3 voltage data
> +
> +power1_input 12v power usage (mW)
> +power2_input 5v power usage (mW)
> +power3_input 3v power usage (mW)
> +power4_input Vee (-12v) power usage (mW)
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index d402e8d..91bec8a 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -836,6 +836,17 @@ config SENSORS_APPLESMC
> Say Y here if you have an applicable laptop and want to experience
> the awesome power of applesmc.
>
> +config SENSORS_LTC4245
> + tristate "Linear Technology LTC4245"
> + depends on I2C && EXPERIMENTAL
> + default n
> + help
> + If you say yes here you get support for Linear Technology LTC4245
> + Multiple Supply Hot Swap Controller I2C interface.
> +
> + This driver can also be built as a module. If so, the module will
> + be called ltc4245.
> +
> config HWMON_DEBUG_CHIP
> bool "Hardware Monitoring Chip debugging messages"
> default n
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 950134a..0ed56ac 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -59,6 +59,7 @@ obj-$(CONFIG_SENSORS_LM87) += lm87.o
> obj-$(CONFIG_SENSORS_LM90) += lm90.o
> obj-$(CONFIG_SENSORS_LM92) += lm92.o
> obj-$(CONFIG_SENSORS_LM93) += lm93.o
> +obj-$(CONFIG_SENSORS_LTC4245) += ltc4245.o
> obj-$(CONFIG_SENSORS_MAX1619) += max1619.o
> obj-$(CONFIG_SENSORS_MAX6650) += max6650.o
> obj-$(CONFIG_SENSORS_PC87360) += pc87360.o
> diff --git a/drivers/hwmon/ltc4245.c b/drivers/hwmon/ltc4245.c
> new file mode 100644
> index 0000000..5d0528b
> --- /dev/null
> +++ b/drivers/hwmon/ltc4245.c
> @@ -0,0 +1,574 @@
> +/*
> + * Driver for Linear Technology LTC4245 I2C Multiple Supply Hot Swap Controller
> + *
> + * Copyright (C) 2008 Ira W. Snyder <iws@ovro.caltech.edu>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; version 2 of the License.
> + *
> + * This driver is based on the ds1621 and ina209 drivers.
> + *
> + * Datasheet:
> + * http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
> + */
> +
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/err.h>
> +#include <linux/slab.h>
> +#include <linux/i2c.h>
> +#include <linux/hwmon.h>
> +#include <linux/hwmon-sysfs.h>
> +
> +/* Addresses to probe */
> +static unsigned short normal_i2c[] = {
> + 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
> + 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
> + 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
> + 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
> + I2C_CLIENT_END};
> +
> +/* Insmod parameters */
> +I2C_CLIENT_INSMOD_1(ltc4245);
> +
> +/* Here are names of the chip's registers (a.k.a. commands) */
> +enum ltc4245_cmd {
> + LTC4245_STATUS = 0x00, /* readonly */
> + LTC4245_ALERT = 0x01,
> + LTC4245_CONTROL = 0x02,
> + LTC4245_ON = 0x03,
> + LTC4245_FAULT1 = 0x04,
> + LTC4245_FAULT2 = 0x05,
> + LTC4245_GPIO = 0x06,
> + LTC4245_ADCADR = 0x07,
> +
> + LTC4245_12VIN = 0x10,
> + LTC4245_12VSENSE = 0x11,
> + LTC4245_12VOUT = 0x12,
> + LTC4245_5VIN = 0x13,
> + LTC4245_5VSENSE = 0x14,
> + LTC4245_5VOUT = 0x15,
> + LTC4245_3VIN = 0x16,
> + LTC4245_3VSENSE = 0x17,
> + LTC4245_3VOUT = 0x18,
> + LTC4245_VEEIN = 0x19,
> + LTC4245_VEESENSE = 0x1a,
> + LTC4245_VEEOUT = 0x1b,
> + LTC4245_GPIOADC1 = 0x1c,
> + LTC4245_GPIOADC2 = 0x1d,
> + LTC4245_GPIOADC3 = 0x1e,
> +};
> +
> +struct ltc4245_data {
> + struct device *hwmon_dev;
> +
> + struct mutex update_lock;
> + bool valid;
> + unsigned long last_updated; /* in jiffies */
> +
> + /* Control registers */
> + u8 cregs[0x08];
> +
> + /* Voltage registers */
> + u8 vregs[0x0f];
> +};
> +
> +/* All registers are byte-sized (8 bit) */
> +static s32 ltc4245_read_reg(struct i2c_client *client, u8 reg)
> +{
> + return i2c_smbus_read_byte_data(client, reg);
> +}
> +
> +#if 0
> +static s32 ltc4245_write_reg(struct i2c_client *client, u8 reg, u8 val)
> +{
> + return i2c_smbus_write_byte_data(client, reg, val);
> +}
> +#endif
> +
> +static struct ltc4245_data *ltc4245_update_device(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct ltc4245_data *data = i2c_get_clientdata(client);
> + int i;
> +
> + mutex_lock(&data->update_lock);
> +
> + if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
> +
> + dev_dbg(&client->dev, "Starting ltc4245 update\n");
> +
> + /* Read control registers -- 0x00 to 0x07 */
> + for (i = 0; i < ARRAY_SIZE(data->cregs); i++)
> + data->cregs[i] = ltc4245_read_reg(client, i);
> +
> + /* Read voltage registers -- 0x10 to 0x1f */
> + for (i = 0; i < ARRAY_SIZE(data->vregs); i++)
> + data->vregs[i] = ltc4245_read_reg(client, i+0x10);
> +
> + data->last_updated = jiffies;
> + data->valid = 1;
> + }
> +
> + mutex_unlock(&data->update_lock);
> +
> + return data;
> +}
> +
> +/* Return the voltage from the given register in millivolts */
> +static int ltc4245_get_voltage(struct device *dev, u8 reg)
> +{
> + struct ltc4245_data *data = ltc4245_update_device(dev);
> + const s32 val = data->vregs[reg - 0x10];
> + const u8 regval = val;
> + u32 voltage = 0;
> +
> + if (unlikely(val < 0))
> + return 0;
> +
> + switch (reg) {
> + case LTC4245_12VIN:
> + case LTC4245_12VOUT:
> + voltage = regval * 55;
> + break;
> + case LTC4245_5VIN:
> + case LTC4245_5VOUT:
> + voltage = regval * 22;
> + break;
> + case LTC4245_3VIN:
> + case LTC4245_3VOUT:
> + voltage = regval * 15;
> + break;
> + case LTC4245_VEEIN:
> + case LTC4245_VEEOUT:
> + voltage = regval * -55;
> + break;
> + case LTC4245_GPIOADC1:
> + case LTC4245_GPIOADC2:
> + case LTC4245_GPIOADC3:
> + voltage = regval * 10;
> + break;
> + default:
> + /* If we get here, the developer messed up */
> + WARN_ON_ONCE(1);
> + break;
> + }
> +
> + return voltage;
> +}
> +
> +/* Return the current in the given sense register in milliAmperes */
> +static u32 ltc4245_get_current(struct device *dev, u8 reg)
> +{
> + struct ltc4245_data *data = ltc4245_update_device(dev);
> + const s32 val = data->vregs[reg - 0x10];
> + const u8 regval = val;
> + u32 voltage;
> + u32 current;
> +
> + if (unlikely(val) < 0)
> + return 0;
> +
> + /* The strange looking conversions that follow are fixed-point
> + * math, since we cannot do floating point in the kernel.
> + *
> + * Step 1: convert sense register to microVolts
> + * Step 2: convert voltage to milliAmperes
> + *
> + * If you play around with the V=IR equation, you come up with
> + * the following: X uV / Y mOhm = Z mA
> + *
> + * With the resistors that are fractions of a milliOhm, we multiply
> + * the voltage and resistance by 10, to shift the decimal point.
> + * Now we can use the normal division operator again.
> + */
> +
> + switch (reg) {
> + case LTC4245_12VSENSE:
> + voltage = regval * 250; /* voltage in uV */
> + current = voltage / 50; /* sense resistor 50 mOhm */
> + break;
> + case LTC4245_5VSENSE:
> + voltage = regval * 125; /* voltage in uV */
> + current = (voltage * 10) / 35; /* sense resistor 3.5 mOhm */
> + break;
> + case LTC4245_3VSENSE:
> + voltage = regval * 125; /* voltage in uV */
> + current = (voltage * 10) / 25; /* sense resistor 2.5 mOhm */
> + break;
> + case LTC4245_VEESENSE:
> + voltage = regval * 250; /* voltage in uV */
> + current = voltage / 100; /* sense resistor 100 mOhm */
> + break;
> + default:
> + /* If we get here, the developer messed up */
> + WARN_ON_ONCE(1);
> + current = 0;
> + break;
> + }
> +
> + return current;
> +}
> +
> +static ssize_t ltc4245_show_voltage(struct device *dev,
> + struct device_attribute *da,
> + char *buf)
> +{
> + struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
> + const u32 voltage = ltc4245_get_voltage(dev, attr->index);
> +
> + return snprintf(buf, PAGE_SIZE, "%d\n", voltage);
> +}
> +
> +static ssize_t ltc4245_show_current(struct device *dev,
> + struct device_attribute *da,
> + char *buf)
> +{
> + struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
> + const u32 current = ltc4245_get_current(dev, attr->index);
> +
> + return snprintf(buf, PAGE_SIZE, "%u\n", current);
> +}
> +
> +static ssize_t ltc4245_show_power(struct device *dev,
> + struct device_attribute *da,
> + char *buf)
> +{
> + struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
> + const u32 current = ltc4245_get_current(dev, attr->index);
> + const u32 output_voltage = ltc4245_get_voltage(dev, attr->index+1);
> +
> + /* current in mA * voltage in mV = power in uW */
> + const unsigned int power = abs(output_voltage * current);
> +
> + return snprintf(buf, PAGE_SIZE, "%u\n", power);
> +}
> +
> +static ssize_t ltc4245_show_alarm(struct device *dev,
> + struct device_attribute *da,
> + char *buf)
> +{
> + struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
> + struct ltc4245_data *data = ltc4245_update_device(dev);
> + const s32 reg = data->cregs[attr->index];
> + const u32 mask = attr->nr;
> +
> + if (unlikely(reg < 0)) {
> + memset(buf, 0, PAGE_SIZE); /* user should not see old data */
> + return 0;
> + }
> +
> + return snprintf(buf, PAGE_SIZE, "%u\n", (reg & mask) ? 1 : 0);
> +}
> +
> +/* These macros are used below in constructing device attribute objects
> + * for use with sysfs_create_group() to make a sysfs device file
> + * for each register.
> + */
> +
> +#define LTC4245_VOLTAGE(name, ltc4245_cmd_idx) \
> + static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
> + ltc4245_show_voltage, NULL, ltc4245_cmd_idx)
> +
> +#define LTC4245_CURRENT(name, ltc4245_cmd_idx) \
> + static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
> + ltc4245_show_current, NULL, ltc4245_cmd_idx)
> +
> +#define LTC4245_POWER(name, ltc4245_cmd_idx) \
> + static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
> + ltc4245_show_power, NULL, ltc4245_cmd_idx)
> +
> +#define LTC4245_ALARM(name, mask, reg) \
> + static SENSOR_DEVICE_ATTR_2(name, S_IRUGO, \
> + ltc4245_show_alarm, NULL, (mask), reg)
> +
> +/* Construct a sensor_device_attribute structure for each register */
> +
> +/* Input voltages */
> +LTC4245_VOLTAGE(in1_input, LTC4245_12VIN);
> +LTC4245_VOLTAGE(in2_input, LTC4245_5VIN);
> +LTC4245_VOLTAGE(in3_input, LTC4245_3VIN);
> +LTC4245_VOLTAGE(in4_input, LTC4245_VEEIN);
> +
> +/* Input undervoltage alarms */
> +LTC4245_ALARM(in1_min_alarm, (1 << 0), LTC4245_FAULT1);
> +LTC4245_ALARM(in2_min_alarm, (1 << 1), LTC4245_FAULT1);
> +LTC4245_ALARM(in3_min_alarm, (1 << 2), LTC4245_FAULT1);
> +LTC4245_ALARM(in4_min_alarm, (1 << 3), LTC4245_FAULT1);
> +
> +/* Currents (via sense resistor) */
> +LTC4245_CURRENT(curr1_input, LTC4245_12VSENSE);
> +LTC4245_CURRENT(curr2_input, LTC4245_5VSENSE);
> +LTC4245_CURRENT(curr3_input, LTC4245_3VSENSE);
> +LTC4245_CURRENT(curr4_input, LTC4245_VEESENSE);
> +
> +/* Overcurrent alarms */
> +LTC4245_ALARM(curr1_max_alarm, (1 << 4), LTC4245_FAULT1);
> +LTC4245_ALARM(curr2_max_alarm, (1 << 5), LTC4245_FAULT1);
> +LTC4245_ALARM(curr3_max_alarm, (1 << 6), LTC4245_FAULT1);
> +LTC4245_ALARM(curr4_max_alarm, (1 << 7), LTC4245_FAULT1);
> +
> +/* Output voltages */
> +LTC4245_VOLTAGE(in5_input, LTC4245_12VOUT);
> +LTC4245_VOLTAGE(in6_input, LTC4245_5VOUT);
> +LTC4245_VOLTAGE(in7_input, LTC4245_3VOUT);
> +LTC4245_VOLTAGE(in8_input, LTC4245_VEEOUT);
> +
> +/* Power Bad alarms */
> +LTC4245_ALARM(in5_min_alarm, (1 << 0), LTC4245_FAULT2);
> +LTC4245_ALARM(in6_min_alarm, (1 << 1), LTC4245_FAULT2);
> +LTC4245_ALARM(in7_min_alarm, (1 << 2), LTC4245_FAULT2);
> +LTC4245_ALARM(in8_min_alarm, (1 << 3), LTC4245_FAULT2);
> +
> +/* GPIO voltages */
> +LTC4245_VOLTAGE(in9_input, LTC4245_GPIOADC1);
> +LTC4245_VOLTAGE(in10_input, LTC4245_GPIOADC2);
> +LTC4245_VOLTAGE(in11_input, LTC4245_GPIOADC3);
> +
> +/* Power Consumption (virtual) */
> +LTC4245_POWER(power1_input, LTC4245_12VSENSE);
> +LTC4245_POWER(power2_input, LTC4245_5VSENSE);
> +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 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 -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;
> +
> + v = ltc4245_read_reg(client, reg) & bits;
> +
> + if (v < 0)
> + return -ENODEV;
> +
> + for (i = 0x00; i < 0xff; i += 0x20) {
> + voff1 = ltc4245_read_reg(client, reg + i) & bits;
> + voff2 = ltc4245_read_reg(client, reg + i + 0x08) & bits;
> +
> + if (voff1 < 0 || voff2 < 0 || 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 = ltc4245_read_reg(client, LTC4245_CONTROL);
> + if (v < 0 || (v & 0x04) != 0)
> + return -ENODEV;
> +
> + /* read register 0x07 reserved bits, expect 0 */
> + v = ltc4245_read_reg(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);
> + pr_info("ltc4245: %s on i2c-%u address 0x%02x\n",
> + kind < 0 ? "probed" : "forced",
> + adapter->nr, 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);
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [lm-sensors] [PATCH] hwmon: Add LTC4245 driver
2008-10-20 16:03 [lm-sensors] [PATCH] hwmon: Add LTC4245 driver Ira Snyder
2008-10-20 17:29 ` Hans de Goede
@ 2008-10-21 12:19 ` Jean Delvare
2008-10-21 12:27 ` Jean Delvare
` (5 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Jean Delvare @ 2008-10-21 12:19 UTC (permalink / raw)
To: lm-sensors
Hi Ira, hi Hans,
On Mon, 20 Oct 2008 09:03:08 -0700, Ira Snyder wrote:
> 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>
> ---
>
> I'm pretty sure this should be the final revision of the driver. Please
> go ahead and forward it upstream. :)
>
> I apologize for the late response. I was having some troubles with my
> email. They should all be sorted out now.
>
> Thanks for all the help and review!
> Ira
>
>
> Changes v3 -> v4:
> * simplify ltc4245_get_voltage(), removing special casing for -12v
> * power should always be a positive value
>
> Changes v2 -> v3:
> * fix units (power?_input in uW, curr?_input in mA)
> * combine all alarm functions
> * rename power[1-4]_alarm to in[5-8]_min_alarm, per suggestions
>
> Changes v1 -> v2:
> * fixed checkpatch warnings
> * removed raw register access, per suggestions
> * changed sysfs interface, per suggestions (current, power, alarms)
Hans, thanks a lot for the reviews. Ira, thanks for going through all
the iterations patiently. My turn now:
>
>
> Documentation/hwmon/ltc4245 | 69 +++++
> drivers/hwmon/Kconfig | 11 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/ltc4245.c | 574 +++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 655 insertions(+), 0 deletions(-)
> create mode 100644 Documentation/hwmon/ltc4245
> create mode 100644 drivers/hwmon/ltc4245.c
>
> diff --git a/Documentation/hwmon/ltc4245 b/Documentation/hwmon/ltc4245
> new file mode 100644
> index 0000000..d2f411a
> --- /dev/null
> +++ b/Documentation/hwmon/ltc4245
> @@ -0,0 +1,69 @@
> +Kernel driver ltc4245
> +==========> +
> +Supported chips:
> + * Linear Technology LTC4245
> + Prefix: 'ltc4245'
> + Addresses scanned: 0x20-0x3f
> + Datasheet:
> + http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
> +
> +Author: Ira W. Snyder <iws@ovro.caltech.edu>
> +
> +
> +Description
> +-----------
> +
> +The LTC4245 controller allows a board to be safely inserted and removed
> +from a live backplane in multiple supply systems such as CompactPCI and
> +PCI Express.
> +
> +
> +Sysfs entries
> +-------------
> +
> +The LTC4245 has built-in limits for over and under current warnings. This
> +makes it very likely that the reference circuit will be used.
> +
> +This driver uses the values in the datasheet to change the register values
> +into the values specified in the sysfs-interface document. The current readings
> +rely on the sense resistors listed in Table 2: "Sense Resistor Values".
> +
> +in1_input 12v input voltage (mV)
> +in2_input 5v input voltage (mV)
> +in3_input 3v input voltage (mV)
> +in4_input Vee (-12v) input voltage (mV)
> +
> +in1_min_alarm 12v input undervoltage alarm
> +in2_min_alarm 5v input undervoltage alarm
> +in3_min_alarm 3v input undervoltage alarm
> +in4_min_alarm Vee (-12v) input undervoltage alarm
> +
> +curr1_input 12v current (mA)
> +curr2_input 5v current (mA)
> +curr3_input 3v current (mA)
> +curr4_input Vee (-12v) current (mA)
> +
> +curr1_max_alarm 12v overcurrent alarm
> +curr2_max_alarm 5v overcurrent alarm
> +curr3_max_alarm 3v overcurrent alarm
> +curr4_max_alarm Vee (-12v) overcurrent alarm
> +
> +in5_input 12v output voltage (mV)
> +in6_input 5v output voltage (mV)
> +in7_input 3v output voltage (mV)
> +in8_input Vee (-12v) output voltage (mV)
> +
> +in5_min_alarm 12v output undervoltage alarm
> +in6_min_alarm 5v output undervoltage alarm
> +in7_min_alarm 3v output undervoltage alarm
> +in8_min_alarm Vee (-12v) output undervoltage alarm
I find it a bit weird to have alarms for limits which do not have sysfs
files themselves. If we know the limits, we could expose them as
read-only attributes (in a future patch)?
> +
> +in9_input GPIO #1 voltage data
> +in10_input GPIO #2 voltage data
> +in11_input GPIO #3 voltage data
> +
> +power1_input 12v power usage (mW)
> +power2_input 5v power usage (mW)
> +power3_input 3v power usage (mW)
> +power4_input Vee (-12v) power usage (mW)
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index d402e8d..91bec8a 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -836,6 +836,17 @@ config SENSORS_APPLESMC
> Say Y here if you have an applicable laptop and want to experience
> the awesome power of applesmc.
>
> +config SENSORS_LTC4245
> + tristate "Linear Technology LTC4245"
> + depends on I2C && EXPERIMENTAL
> + default n
> + help
> + If you say yes here you get support for Linear Technology LTC4245
> + Multiple Supply Hot Swap Controller I2C interface.
> +
> + This driver can also be built as a module. If so, the module will
> + be called ltc4245.
> +
> config HWMON_DEBUG_CHIP
> bool "Hardware Monitoring Chip debugging messages"
> default n
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 950134a..0ed56ac 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -59,6 +59,7 @@ obj-$(CONFIG_SENSORS_LM87) += lm87.o
> obj-$(CONFIG_SENSORS_LM90) += lm90.o
> obj-$(CONFIG_SENSORS_LM92) += lm92.o
> obj-$(CONFIG_SENSORS_LM93) += lm93.o
> +obj-$(CONFIG_SENSORS_LTC4245) += ltc4245.o
> obj-$(CONFIG_SENSORS_MAX1619) += max1619.o
> obj-$(CONFIG_SENSORS_MAX6650) += max6650.o
> obj-$(CONFIG_SENSORS_PC87360) += pc87360.o
> diff --git a/drivers/hwmon/ltc4245.c b/drivers/hwmon/ltc4245.c
> new file mode 100644
> index 0000000..5d0528b
> --- /dev/null
> +++ b/drivers/hwmon/ltc4245.c
> @@ -0,0 +1,574 @@
> +/*
> + * Driver for Linear Technology LTC4245 I2C Multiple Supply Hot Swap Controller
> + *
> + * Copyright (C) 2008 Ira W. Snyder <iws@ovro.caltech.edu>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; version 2 of the License.
> + *
> + * This driver is based on the ds1621 and ina209 drivers.
> + *
> + * Datasheet:
> + * http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
> + */
> +
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/err.h>
> +#include <linux/slab.h>
> +#include <linux/i2c.h>
> +#include <linux/hwmon.h>
> +#include <linux/hwmon-sysfs.h>
> +
> +/* Addresses to probe */
> +static unsigned short normal_i2c[] = {
Should be const.
> + 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
> + 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
> + 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
> + 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
> + I2C_CLIENT_END};
That's a lot of addresses. This has several drawbacks:
* This can make driver loading very slow on systems with many I2C
buses, especially as you read from a lot of registers in your detect
function.
* Some of these addresses (0x30-0x3f) are known to be
probing-unfriendly. With such a large range of probes, the risk that
you hit a chip which misbehaves on probe is high.
* As the LTC4245 doesn't have dedicated identification registers, you
have to rely on heuristics, which may yield to false positives. I see
that you have gone to quite some extent to make detection as good as
possible, however the LTC4245 isn't the only chip out there which
ignores the high bits of the register address, and checking for bits
being 0 isn't terribly reliable (most I2C devices return 0x00 as the
value of unused registers.)
So I'd rather limit the probing to addresses where the LTC4245 is
commonly found. Or even drop probing entirely. I don't expect these
chips to appear on mainstream hardware, probably it is only used in
specialized equipment, and there you know at which address it lives so
you don't need to probe for it? I would hope that you can simply
instantiate the i2c client explicitly where needed.
> +
> +/* Insmod parameters */
> +I2C_CLIENT_INSMOD_1(ltc4245);
> +
> +/* Here are names of the chip's registers (a.k.a. commands) */
> +enum ltc4245_cmd {
> + LTC4245_STATUS = 0x00, /* readonly */
> + LTC4245_ALERT = 0x01,
> + LTC4245_CONTROL = 0x02,
> + LTC4245_ON = 0x03,
> + LTC4245_FAULT1 = 0x04,
> + LTC4245_FAULT2 = 0x05,
> + LTC4245_GPIO = 0x06,
> + LTC4245_ADCADR = 0x07,
> +
> + LTC4245_12VIN = 0x10,
> + LTC4245_12VSENSE = 0x11,
> + LTC4245_12VOUT = 0x12,
> + LTC4245_5VIN = 0x13,
> + LTC4245_5VSENSE = 0x14,
> + LTC4245_5VOUT = 0x15,
> + LTC4245_3VIN = 0x16,
> + LTC4245_3VSENSE = 0x17,
> + LTC4245_3VOUT = 0x18,
> + LTC4245_VEEIN = 0x19,
> + LTC4245_VEESENSE = 0x1a,
> + LTC4245_VEEOUT = 0x1b,
> + LTC4245_GPIOADC1 = 0x1c,
> + LTC4245_GPIOADC2 = 0x1d,
> + LTC4245_GPIOADC3 = 0x1e,
> +};
> +
> +struct ltc4245_data {
> + struct device *hwmon_dev;
> +
> + struct mutex update_lock;
> + bool valid;
> + unsigned long last_updated; /* in jiffies */
> +
> + /* Control registers */
> + u8 cregs[0x08];
> +
> + /* Voltage registers */
> + u8 vregs[0x0f];
> +};
> +
> +/* All registers are byte-sized (8 bit) */
> +static s32 ltc4245_read_reg(struct i2c_client *client, u8 reg)
> +{
> + return i2c_smbus_read_byte_data(client, reg);
> +}
This function doesn't strike me as very useful. At the very least it
should be declared inline, but it could as well be dropped.
> +
> +#if 0
> +static s32 ltc4245_write_reg(struct i2c_client *client, u8 reg, u8 val)
> +{
> + return i2c_smbus_write_byte_data(client, reg, val);
> +}
> +#endif
Don't include this at all if you don't need it.
> +
> +static struct ltc4245_data *ltc4245_update_device(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct ltc4245_data *data = i2c_get_clientdata(client);
> + int i;
> +
> + mutex_lock(&data->update_lock);
> +
> + if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
> +
> + dev_dbg(&client->dev, "Starting ltc4245 update\n");
> +
> + /* Read control registers -- 0x00 to 0x07 */
> + for (i = 0; i < ARRAY_SIZE(data->cregs); i++)
> + data->cregs[i] = ltc4245_read_reg(client, i);
> +
> + /* Read voltage registers -- 0x10 to 0x1f */
> + for (i = 0; i < ARRAY_SIZE(data->vregs); i++)
> + data->vregs[i] = ltc4245_read_reg(client, i+0x10);
> +
> + data->last_updated = jiffies;
> + data->valid = 1;
> + }
> +
> + mutex_unlock(&data->update_lock);
> +
> + return data;
> +}
> +
> +/* Return the voltage from the given register in millivolts */
> +static int ltc4245_get_voltage(struct device *dev, u8 reg)
> +{
> + struct ltc4245_data *data = ltc4245_update_device(dev);
> + const s32 val = data->vregs[reg - 0x10];
> + const u8 regval = val;
> + u32 voltage = 0;
> +
> + if (unlikely(val < 0))
> + return 0;
It's not unlikely, it's impossible. data->vregs is an array of u8.
> +
> + switch (reg) {
> + case LTC4245_12VIN:
> + case LTC4245_12VOUT:
> + voltage = regval * 55;
> + break;
> + case LTC4245_5VIN:
> + case LTC4245_5VOUT:
> + voltage = regval * 22;
> + break;
> + case LTC4245_3VIN:
> + case LTC4245_3VOUT:
> + voltage = regval * 15;
> + break;
> + case LTC4245_VEEIN:
> + case LTC4245_VEEOUT:
> + voltage = regval * -55;
> + break;
> + case LTC4245_GPIOADC1:
> + case LTC4245_GPIOADC2:
> + case LTC4245_GPIOADC3:
> + voltage = regval * 10;
> + break;
> + default:
> + /* If we get here, the developer messed up */
> + WARN_ON_ONCE(1);
> + break;
> + }
I am under the impression that a 11-element array of scaling factors
would work much better - but it's up to you.
> +
> + return voltage;
> +}
> +
> +/* Return the current in the given sense register in milliAmperes */
> +static u32 ltc4245_get_current(struct device *dev, u8 reg)
> +{
> + struct ltc4245_data *data = ltc4245_update_device(dev);
> + const s32 val = data->vregs[reg - 0x10];
> + const u8 regval = val;
> + u32 voltage;
> + u32 current;
> +
> + if (unlikely(val) < 0)
> + return 0;
Same as above, this simply can't happen.
> +
> + /* The strange looking conversions that follow are fixed-point
> + * math, since we cannot do floating point in the kernel.
> + *
> + * Step 1: convert sense register to microVolts
> + * Step 2: convert voltage to milliAmperes
> + *
> + * If you play around with the V=IR equation, you come up with
> + * the following: X uV / Y mOhm = Z mA
> + *
> + * With the resistors that are fractions of a milliOhm, we multiply
> + * the voltage and resistance by 10, to shift the decimal point.
> + * Now we can use the normal division operator again.
> + */
> +
> + switch (reg) {
> + case LTC4245_12VSENSE:
> + voltage = regval * 250; /* voltage in uV */
> + current = voltage / 50; /* sense resistor 50 mOhm */
> + break;
> + case LTC4245_5VSENSE:
> + voltage = regval * 125; /* voltage in uV */
> + current = (voltage * 10) / 35; /* sense resistor 3.5 mOhm */
> + break;
> + case LTC4245_3VSENSE:
> + voltage = regval * 125; /* voltage in uV */
> + current = (voltage * 10) / 25; /* sense resistor 2.5 mOhm */
> + break;
> + case LTC4245_VEESENSE:
> + voltage = regval * 250; /* voltage in uV */
> + current = voltage / 100; /* sense resistor 100 mOhm */
> + break;
> + default:
> + /* If we get here, the developer messed up */
> + WARN_ON_ONCE(1);
> + current = 0;
> + break;
> + }
> +
> + return current;
> +}
> +
> +static ssize_t ltc4245_show_voltage(struct device *dev,
> + struct device_attribute *da,
> + char *buf)
> +{
> + struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
> + const u32 voltage = ltc4245_get_voltage(dev, attr->index);
> +
> + return snprintf(buf, PAGE_SIZE, "%d\n", voltage);
Seems inconsistent to store the voltage in a u32 and print it with %d.
As ltc4245_get_voltage() returns an int, why don't you declare voltage
an int as well?
> +}
> +
> +static ssize_t ltc4245_show_current(struct device *dev,
> + struct device_attribute *da,
> + char *buf)
> +{
> + struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
> + const u32 current = ltc4245_get_current(dev, attr->index);
> +
> + return snprintf(buf, PAGE_SIZE, "%u\n", current);
> +}
> +
> +static ssize_t ltc4245_show_power(struct device *dev,
> + struct device_attribute *da,
> + char *buf)
> +{
> + struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
> + const u32 current = ltc4245_get_current(dev, attr->index);
> + const u32 output_voltage = ltc4245_get_voltage(dev, attr->index+1);
> +
> + /* current in mA * voltage in mV = power in uW */
> + const unsigned int power = abs(output_voltage * current);
abs() is defined in <linux/kernel.h>, which you didn't include.
> +
> + return snprintf(buf, PAGE_SIZE, "%u\n", power);
> +}
> +
> +static ssize_t ltc4245_show_alarm(struct device *dev,
> + struct device_attribute *da,
> + char *buf)
> +{
> + struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
> + struct ltc4245_data *data = ltc4245_update_device(dev);
> + const s32 reg = data->cregs[attr->index];
> + const u32 mask = attr->nr;
> +
> + if (unlikely(reg < 0)) {
> + memset(buf, 0, PAGE_SIZE); /* user should not see old data */
> + return 0;
> + }
Same as above, this simply can't happen.
And as a side note, you don't bother zeroing the rest of the page on
success, so I can't see why you insist on doing it on failure.
> +
> + return snprintf(buf, PAGE_SIZE, "%u\n", (reg & mask) ? 1 : 0);
> +}
> +
> +/* These macros are used below in constructing device attribute objects
> + * for use with sysfs_create_group() to make a sysfs device file
> + * for each register.
> + */
> +
> +#define LTC4245_VOLTAGE(name, ltc4245_cmd_idx) \
> + static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
> + ltc4245_show_voltage, NULL, ltc4245_cmd_idx)
> +
> +#define LTC4245_CURRENT(name, ltc4245_cmd_idx) \
> + static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
> + ltc4245_show_current, NULL, ltc4245_cmd_idx)
> +
> +#define LTC4245_POWER(name, ltc4245_cmd_idx) \
> + static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
> + ltc4245_show_power, NULL, ltc4245_cmd_idx)
> +
> +#define LTC4245_ALARM(name, mask, reg) \
> + static SENSOR_DEVICE_ATTR_2(name, S_IRUGO, \
> + ltc4245_show_alarm, NULL, (mask), reg)
> +
> +/* Construct a sensor_device_attribute structure for each register */
> +
> +/* Input voltages */
> +LTC4245_VOLTAGE(in1_input, LTC4245_12VIN);
> +LTC4245_VOLTAGE(in2_input, LTC4245_5VIN);
> +LTC4245_VOLTAGE(in3_input, LTC4245_3VIN);
> +LTC4245_VOLTAGE(in4_input, LTC4245_VEEIN);
> +
> +/* Input undervoltage alarms */
> +LTC4245_ALARM(in1_min_alarm, (1 << 0), LTC4245_FAULT1);
> +LTC4245_ALARM(in2_min_alarm, (1 << 1), LTC4245_FAULT1);
> +LTC4245_ALARM(in3_min_alarm, (1 << 2), LTC4245_FAULT1);
> +LTC4245_ALARM(in4_min_alarm, (1 << 3), LTC4245_FAULT1);
> +
> +/* Currents (via sense resistor) */
> +LTC4245_CURRENT(curr1_input, LTC4245_12VSENSE);
> +LTC4245_CURRENT(curr2_input, LTC4245_5VSENSE);
> +LTC4245_CURRENT(curr3_input, LTC4245_3VSENSE);
> +LTC4245_CURRENT(curr4_input, LTC4245_VEESENSE);
> +
> +/* Overcurrent alarms */
> +LTC4245_ALARM(curr1_max_alarm, (1 << 4), LTC4245_FAULT1);
> +LTC4245_ALARM(curr2_max_alarm, (1 << 5), LTC4245_FAULT1);
> +LTC4245_ALARM(curr3_max_alarm, (1 << 6), LTC4245_FAULT1);
> +LTC4245_ALARM(curr4_max_alarm, (1 << 7), LTC4245_FAULT1);
> +
> +/* Output voltages */
> +LTC4245_VOLTAGE(in5_input, LTC4245_12VOUT);
> +LTC4245_VOLTAGE(in6_input, LTC4245_5VOUT);
> +LTC4245_VOLTAGE(in7_input, LTC4245_3VOUT);
> +LTC4245_VOLTAGE(in8_input, LTC4245_VEEOUT);
> +
> +/* Power Bad alarms */
> +LTC4245_ALARM(in5_min_alarm, (1 << 0), LTC4245_FAULT2);
> +LTC4245_ALARM(in6_min_alarm, (1 << 1), LTC4245_FAULT2);
> +LTC4245_ALARM(in7_min_alarm, (1 << 2), LTC4245_FAULT2);
> +LTC4245_ALARM(in8_min_alarm, (1 << 3), LTC4245_FAULT2);
> +
> +/* GPIO voltages */
> +LTC4245_VOLTAGE(in9_input, LTC4245_GPIOADC1);
> +LTC4245_VOLTAGE(in10_input, LTC4245_GPIOADC2);
> +LTC4245_VOLTAGE(in11_input, LTC4245_GPIOADC3);
> +
> +/* Power Consumption (virtual) */
> +LTC4245_POWER(power1_input, LTC4245_12VSENSE);
> +LTC4245_POWER(power2_input, LTC4245_5VSENSE);
> +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 struct attribute_group ltc4245_group = {
Should be const.
> + .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) {
Coding style: no blank line between function call and error test.
> + 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)
Same here...
> + goto out_sysfs_create_group;
> +
> + data->hwmon_dev = hwmon_device_register(&client->dev);
> +
... and here.
> + 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 -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;
> +
> + v = ltc4245_read_reg(client, reg) & bits;
ltc4245_read_reg may return an error. Masking error values usually
isn't what you want ;) Check for < 0 first and mask only after that.
Same problem below.
> +
> + if (v < 0)
> + return -ENODEV;
> +
> + for (i = 0x00; i < 0xff; i += 0x20) {
> + voff1 = ltc4245_read_reg(client, reg + i) & bits;
> + voff2 = ltc4245_read_reg(client, reg + i + 0x08) & bits;
> +
> + if (voff1 < 0 || voff2 < 0 || 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 = ltc4245_read_reg(client, LTC4245_CONTROL);
Note: you should never call device-specific read functions in detect
functions, as by definition you don't yet know which device you have.
> + if (v < 0 || (v & 0x04) != 0)
> + return -ENODEV;
> +
> + /* read register 0x07 reserved bits, expect 0 */
> + v = ltc4245_read_reg(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);
> + pr_info("ltc4245: %s on i2c-%u address 0x%02x\n",
> + kind < 0 ? "probed" : "forced",
> + adapter->nr, client->addr);
Please use dev_info(&adapter->dev, ...) instead.
> +
> + 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);
--
Jean Delvare
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [lm-sensors] [PATCH] hwmon: Add LTC4245 driver
2008-10-20 16:03 [lm-sensors] [PATCH] hwmon: Add LTC4245 driver Ira Snyder
2008-10-20 17:29 ` Hans de Goede
2008-10-21 12:19 ` Jean Delvare
@ 2008-10-21 12:27 ` Jean Delvare
2008-10-21 12:50 ` Jean Delvare
` (4 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Jean Delvare @ 2008-10-21 12:27 UTC (permalink / raw)
To: lm-sensors
On Mon, 20 Oct 2008 19:29:50 +0200, Hans de Goede wrote:
>
>
> Ira Snyder wrote:
> > 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>
> > ---
> >
> > I'm pretty sure this should be the final revision of the driver. Please
> > go ahead and forward it upstream. :)
> >
>
> Looks good now :)
>
> Jean, can you put this patch in your for Linus for 2.6.28 queue please?
>
> This is:
> Reviewed-by: Hans de Goede <hdegoede@redhat.com>
> or
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>
> Whatever you deem more appropriate.
Actually that would be:
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by would technically require that you resend the patch to me.
--
Jean Delvare
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [lm-sensors] [PATCH] hwmon: Add LTC4245 driver
2008-10-20 16:03 [lm-sensors] [PATCH] hwmon: Add LTC4245 driver Ira Snyder
` (2 preceding siblings ...)
2008-10-21 12:27 ` Jean Delvare
@ 2008-10-21 12:50 ` Jean Delvare
2008-10-21 17:44 ` Ira Snyder
` (3 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Jean Delvare @ 2008-10-21 12:50 UTC (permalink / raw)
To: lm-sensors
Oh, BTW... Your driver doesn't build:
drivers/hwmon/ltc4245.c: In function ‘ltc4245_get_current’:
drivers/hwmon/ltc4245.c:168: warning: function declaration isn’t a prototype
drivers/hwmon/ltc4245.c:168: error: conflicting types for ‘get_current’
include/asm/current.h:24: error: previous definition of ‘get_current’ was here
Apparently get_current is a global symbol already so you will need to
come up with a different name. Prefixing your function names with the
driver name is usually a good way to protect against this.
Thanks,
--
Jean Delvare
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply [flat|nested] 9+ messages in thread
* [lm-sensors] [PATCH] hwmon: Add LTC4245 driver
2008-10-20 16:03 [lm-sensors] [PATCH] hwmon: Add LTC4245 driver Ira Snyder
` (3 preceding siblings ...)
2008-10-21 12:50 ` Jean Delvare
@ 2008-10-21 17:44 ` Ira Snyder
2008-10-22 7:21 ` Jean Delvare
` (2 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Ira Snyder @ 2008-10-21 17:44 UTC (permalink / raw)
To: lm-sensors
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>
---
This should be the final revision of the driver. For real this time :)
Jean, please feel free to just delete the "#if 0" block if you feel it
shouldn't be there. The comment is just fine.
Changes v4 -> v5:
* rename the variable "current" to "curr" to workaround brokenness
in asm/current.h on x86, powerpc64, etc.
* check for errors when reading from i2c
* disable probing, add example usage of force param to documentation
* add missing #include <linux/kernel.h>
* use i2c_smbus_read_byte_data() rather than ltc4245_read_reg()
* const-ify some variables
Changes v3 -> v4:
* simplify ltc4245_get_voltage(), removing special casing for -12v
* power should always be a positive value
Changes v2 -> v3:
* fix units (power?_input in uW, curr?_input in mA)
* combine all alarm functions
* rename power[1-4]_alarm to in[5-8]_min_alarm, per suggestions
Changes v1 -> v2:
* fixed checkpatch warnings
* removed raw register access, per suggestions
* changed sysfs interface, per suggestions (current, power, alarms)
Documentation/hwmon/ltc4245 | 81 ++++++
drivers/hwmon/Kconfig | 11 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/ltc4245.c | 578 +++++++++++++++++++++++++++++++++++++++++++
4 files changed, 671 insertions(+), 0 deletions(-)
create mode 100644 Documentation/hwmon/ltc4245
create mode 100644 drivers/hwmon/ltc4245.c
diff --git a/Documentation/hwmon/ltc4245 b/Documentation/hwmon/ltc4245
new file mode 100644
index 0000000..27e9d67
--- /dev/null
+++ b/Documentation/hwmon/ltc4245
@@ -0,0 +1,81 @@
+Kernel driver ltc4245
+==========+
+Supported chips:
+ * Linear Technology LTC4245
+ Prefix: 'ltc4245'
+ Addresses scanned: 0x20-0x3f
+ Datasheet:
+ http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
+
+Author: Ira W. Snyder <iws@ovro.caltech.edu>
+
+
+Description
+-----------
+
+The LTC4245 controller allows a board to be safely inserted and removed
+from a live backplane in multiple supply systems such as CompactPCI and
+PCI Express.
+
+
+Usage Notes
+-------------
+
+This driver does not probe for LTC4245 devices, due to the fact that some
+of the possible addresses are unfriendly to probing. You will need to use
+the "force" parameter to tell the driver where to find the device.
+
+Example: the following will load the driver for an LTC4245 at address 0x23
+on I2C bus #1:
+$ modprobe ltc4245 force=1,0x23
+
+
+Sysfs entries
+-------------
+
+The LTC4245 has built-in limits for over and under current warnings. This
+makes it very likely that the reference circuit will be used.
+
+This driver uses the values in the datasheet to change the register values
+into the values specified in the sysfs-interface document. The current readings
+rely on the sense resistors listed in Table 2: "Sense Resistor Values".
+
+in1_input 12v input voltage (mV)
+in2_input 5v input voltage (mV)
+in3_input 3v input voltage (mV)
+in4_input Vee (-12v) input voltage (mV)
+
+in1_min_alarm 12v input undervoltage alarm
+in2_min_alarm 5v input undervoltage alarm
+in3_min_alarm 3v input undervoltage alarm
+in4_min_alarm Vee (-12v) input undervoltage alarm
+
+curr1_input 12v current (mA)
+curr2_input 5v current (mA)
+curr3_input 3v current (mA)
+curr4_input Vee (-12v) current (mA)
+
+curr1_max_alarm 12v overcurrent alarm
+curr2_max_alarm 5v overcurrent alarm
+curr3_max_alarm 3v overcurrent alarm
+curr4_max_alarm Vee (-12v) overcurrent alarm
+
+in5_input 12v output voltage (mV)
+in6_input 5v output voltage (mV)
+in7_input 3v output voltage (mV)
+in8_input Vee (-12v) output voltage (mV)
+
+in5_min_alarm 12v output undervoltage alarm
+in6_min_alarm 5v output undervoltage alarm
+in7_min_alarm 3v output undervoltage alarm
+in8_min_alarm Vee (-12v) output undervoltage alarm
+
+in9_input GPIO #1 voltage data
+in10_input GPIO #2 voltage data
+in11_input GPIO #3 voltage data
+
+power1_input 12v power usage (mW)
+power2_input 5v power usage (mW)
+power3_input 3v power usage (mW)
+power4_input Vee (-12v) power usage (mW)
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 6de1e0f..416f620 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -850,6 +850,17 @@ config SENSORS_APPLESMC
Say Y here if you have an applicable laptop and want to experience
the awesome power of applesmc.
+config SENSORS_LTC4245
+ tristate "Linear Technology LTC4245"
+ depends on I2C && EXPERIMENTAL
+ default n
+ help
+ If you say yes here you get support for Linear Technology LTC4245
+ Multiple Supply Hot Swap Controller I2C interface.
+
+ This driver can also be built as a module. If so, the module will
+ be called ltc4245.
+
config HWMON_DEBUG_CHIP
bool "Hardware Monitoring Chip debugging messages"
default n
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 042d5a7..8f2f412 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -60,6 +60,7 @@ obj-$(CONFIG_SENSORS_LM87) += lm87.o
obj-$(CONFIG_SENSORS_LM90) += lm90.o
obj-$(CONFIG_SENSORS_LM92) += lm92.o
obj-$(CONFIG_SENSORS_LM93) += lm93.o
+obj-$(CONFIG_SENSORS_LTC4245) += ltc4245.o
obj-$(CONFIG_SENSORS_MAX1111) += max1111.o
obj-$(CONFIG_SENSORS_MAX1619) += max1619.o
obj-$(CONFIG_SENSORS_MAX6650) += max6650.o
diff --git a/drivers/hwmon/ltc4245.c b/drivers/hwmon/ltc4245.c
new file mode 100644
index 0000000..cef4b3a
--- /dev/null
+++ b/drivers/hwmon/ltc4245.c
@@ -0,0 +1,578 @@
+/*
+ * Driver for Linear Technology LTC4245 I2C Multiple Supply Hot Swap Controller
+ *
+ * Copyright (C) 2008 Ira W. Snyder <iws@ovro.caltech.edu>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This driver is based on the ds1621 and ina209 drivers.
+ *
+ * Datasheet:
+ * http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+/* Valid addresses are 0x20 - 0x3f
+ *
+ * For now, we do not probe, since some of these addresses
+ * are known to be unfriendly to probing */
+static const unsigned short normal_i2c[] = {
+#if 0
+ 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
+ 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
+ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
+ 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
+#endif
+ I2C_CLIENT_END};
+
+/* Insmod parameters */
+I2C_CLIENT_INSMOD_1(ltc4245);
+
+/* Here are names of the chip's registers (a.k.a. commands) */
+enum ltc4245_cmd {
+ LTC4245_STATUS = 0x00, /* readonly */
+ LTC4245_ALERT = 0x01,
+ LTC4245_CONTROL = 0x02,
+ LTC4245_ON = 0x03,
+ LTC4245_FAULT1 = 0x04,
+ LTC4245_FAULT2 = 0x05,
+ LTC4245_GPIO = 0x06,
+ LTC4245_ADCADR = 0x07,
+
+ LTC4245_12VIN = 0x10,
+ LTC4245_12VSENSE = 0x11,
+ LTC4245_12VOUT = 0x12,
+ LTC4245_5VIN = 0x13,
+ LTC4245_5VSENSE = 0x14,
+ LTC4245_5VOUT = 0x15,
+ LTC4245_3VIN = 0x16,
+ LTC4245_3VSENSE = 0x17,
+ LTC4245_3VOUT = 0x18,
+ LTC4245_VEEIN = 0x19,
+ LTC4245_VEESENSE = 0x1a,
+ LTC4245_VEEOUT = 0x1b,
+ LTC4245_GPIOADC1 = 0x1c,
+ LTC4245_GPIOADC2 = 0x1d,
+ LTC4245_GPIOADC3 = 0x1e,
+};
+
+struct ltc4245_data {
+ struct device *hwmon_dev;
+
+ struct mutex update_lock;
+ bool valid;
+ unsigned long last_updated; /* in jiffies */
+
+ /* Control registers */
+ s32 cregs[0x08];
+
+ /* Voltage registers */
+ s32 vregs[0x0f];
+};
+
+static struct ltc4245_data *ltc4245_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ltc4245_data *data = i2c_get_clientdata(client);
+ int i;
+
+ mutex_lock(&data->update_lock);
+
+ if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+
+ dev_dbg(&client->dev, "Starting ltc4245 update\n");
+
+ /* Read control registers -- 0x00 to 0x07 */
+ for (i = 0; i < ARRAY_SIZE(data->cregs); i++)
+ data->cregs[i] = i2c_smbus_read_byte_data(client, i);
+
+ /* Read voltage registers -- 0x10 to 0x1f */
+ for (i = 0; i < ARRAY_SIZE(data->vregs); i++) {
+ data->vregs[i] = i2c_smbus_read_byte_data(client,
+ i+0x10);
+ }
+
+ data->last_updated = jiffies;
+ data->valid = 1;
+ }
+
+ mutex_unlock(&data->update_lock);
+
+ return data;
+}
+
+/* Return the voltage from the given register in millivolts */
+static int ltc4245_get_voltage(struct device *dev, u8 reg)
+{
+ struct ltc4245_data *data = ltc4245_update_device(dev);
+ const s32 val = data->vregs[reg - 0x10];
+ const u8 regval = val;
+ u32 voltage = 0;
+
+ if (unlikely(val < 0))
+ return 0;
+
+ switch (reg) {
+ case LTC4245_12VIN:
+ case LTC4245_12VOUT:
+ voltage = regval * 55;
+ break;
+ case LTC4245_5VIN:
+ case LTC4245_5VOUT:
+ voltage = regval * 22;
+ break;
+ case LTC4245_3VIN:
+ case LTC4245_3VOUT:
+ voltage = regval * 15;
+ break;
+ case LTC4245_VEEIN:
+ case LTC4245_VEEOUT:
+ voltage = regval * -55;
+ break;
+ case LTC4245_GPIOADC1:
+ case LTC4245_GPIOADC2:
+ case LTC4245_GPIOADC3:
+ voltage = regval * 10;
+ break;
+ default:
+ /* If we get here, the developer messed up */
+ WARN_ON_ONCE(1);
+ break;
+ }
+
+ return voltage;
+}
+
+/* Return the current in the given sense register in milliAmperes */
+static unsigned int ltc4245_get_current(struct device *dev, u8 reg)
+{
+ struct ltc4245_data *data = ltc4245_update_device(dev);
+ const s32 val = data->vregs[reg - 0x10];
+ const u8 regval = val;
+ unsigned int voltage;
+ unsigned int curr;
+
+ if (unlikely(val) < 0)
+ return 0;
+
+ /* The strange looking conversions that follow are fixed-point
+ * math, since we cannot do floating point in the kernel.
+ *
+ * Step 1: convert sense register to microVolts
+ * Step 2: convert voltage to milliAmperes
+ *
+ * If you play around with the V=IR equation, you come up with
+ * the following: X uV / Y mOhm = Z mA
+ *
+ * With the resistors that are fractions of a milliOhm, we multiply
+ * the voltage and resistance by 10, to shift the decimal point.
+ * Now we can use the normal division operator again.
+ */
+
+ switch (reg) {
+ case LTC4245_12VSENSE:
+ voltage = regval * 250; /* voltage in uV */
+ curr = voltage / 50; /* sense resistor 50 mOhm */
+ break;
+ case LTC4245_5VSENSE:
+ voltage = regval * 125; /* voltage in uV */
+ curr = (voltage * 10) / 35; /* sense resistor 3.5 mOhm */
+ break;
+ case LTC4245_3VSENSE:
+ voltage = regval * 125; /* voltage in uV */
+ curr = (voltage * 10) / 25; /* sense resistor 2.5 mOhm */
+ break;
+ case LTC4245_VEESENSE:
+ voltage = regval * 250; /* voltage in uV */
+ curr = voltage / 100; /* sense resistor 100 mOhm */
+ break;
+ default:
+ /* If we get here, the developer messed up */
+ WARN_ON_ONCE(1);
+ curr = 0;
+ break;
+ }
+
+ return curr;
+}
+
+static ssize_t ltc4245_show_voltage(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const int voltage = ltc4245_get_voltage(dev, attr->index);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", voltage);
+}
+
+static ssize_t ltc4245_show_current(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const unsigned int curr = ltc4245_get_current(dev, attr->index);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", curr);
+}
+
+static ssize_t ltc4245_show_power(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const unsigned int curr = ltc4245_get_current(dev, attr->index);
+ const int output_voltage = ltc4245_get_voltage(dev, attr->index+1);
+
+ /* current in mA * voltage in mV = power in uW */
+ const unsigned int power = abs(output_voltage * curr);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", power);
+}
+
+static ssize_t ltc4245_show_alarm(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
+ struct ltc4245_data *data = ltc4245_update_device(dev);
+ const s32 reg = data->cregs[attr->index];
+ const u32 mask = attr->nr;
+
+ if (unlikely(reg < 0))
+ return 0;
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", (reg & mask) ? 1 : 0);
+}
+
+/* These macros are used below in constructing device attribute objects
+ * for use with sysfs_create_group() to make a sysfs device file
+ * for each register.
+ */
+
+#define LTC4245_VOLTAGE(name, ltc4245_cmd_idx) \
+ static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+ ltc4245_show_voltage, NULL, ltc4245_cmd_idx)
+
+#define LTC4245_CURRENT(name, ltc4245_cmd_idx) \
+ static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+ ltc4245_show_current, NULL, ltc4245_cmd_idx)
+
+#define LTC4245_POWER(name, ltc4245_cmd_idx) \
+ static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+ ltc4245_show_power, NULL, ltc4245_cmd_idx)
+
+#define LTC4245_ALARM(name, mask, reg) \
+ static SENSOR_DEVICE_ATTR_2(name, S_IRUGO, \
+ ltc4245_show_alarm, NULL, (mask), reg)
+
+/* Construct a sensor_device_attribute structure for each register */
+
+/* Input voltages */
+LTC4245_VOLTAGE(in1_input, LTC4245_12VIN);
+LTC4245_VOLTAGE(in2_input, LTC4245_5VIN);
+LTC4245_VOLTAGE(in3_input, LTC4245_3VIN);
+LTC4245_VOLTAGE(in4_input, LTC4245_VEEIN);
+
+/* Input undervoltage alarms */
+LTC4245_ALARM(in1_min_alarm, (1 << 0), LTC4245_FAULT1);
+LTC4245_ALARM(in2_min_alarm, (1 << 1), LTC4245_FAULT1);
+LTC4245_ALARM(in3_min_alarm, (1 << 2), LTC4245_FAULT1);
+LTC4245_ALARM(in4_min_alarm, (1 << 3), LTC4245_FAULT1);
+
+/* Currents (via sense resistor) */
+LTC4245_CURRENT(curr1_input, LTC4245_12VSENSE);
+LTC4245_CURRENT(curr2_input, LTC4245_5VSENSE);
+LTC4245_CURRENT(curr3_input, LTC4245_3VSENSE);
+LTC4245_CURRENT(curr4_input, LTC4245_VEESENSE);
+
+/* Overcurrent alarms */
+LTC4245_ALARM(curr1_max_alarm, (1 << 4), LTC4245_FAULT1);
+LTC4245_ALARM(curr2_max_alarm, (1 << 5), LTC4245_FAULT1);
+LTC4245_ALARM(curr3_max_alarm, (1 << 6), LTC4245_FAULT1);
+LTC4245_ALARM(curr4_max_alarm, (1 << 7), LTC4245_FAULT1);
+
+/* Output voltages */
+LTC4245_VOLTAGE(in5_input, LTC4245_12VOUT);
+LTC4245_VOLTAGE(in6_input, LTC4245_5VOUT);
+LTC4245_VOLTAGE(in7_input, LTC4245_3VOUT);
+LTC4245_VOLTAGE(in8_input, LTC4245_VEEOUT);
+
+/* Power Bad alarms */
+LTC4245_ALARM(in5_min_alarm, (1 << 0), LTC4245_FAULT2);
+LTC4245_ALARM(in6_min_alarm, (1 << 1), LTC4245_FAULT2);
+LTC4245_ALARM(in7_min_alarm, (1 << 2), LTC4245_FAULT2);
+LTC4245_ALARM(in8_min_alarm, (1 << 3), LTC4245_FAULT2);
+
+/* GPIO voltages */
+LTC4245_VOLTAGE(in9_input, LTC4245_GPIOADC1);
+LTC4245_VOLTAGE(in10_input, LTC4245_GPIOADC2);
+LTC4245_VOLTAGE(in11_input, LTC4245_GPIOADC3);
+
+/* Power Consumption (virtual) */
+LTC4245_POWER(power1_input, LTC4245_12VSENSE);
+LTC4245_POWER(power2_input, LTC4245_5VSENSE);
+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;
+ if (v < 0)
+ return -ENODEV;
+
+ 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);
--
1.5.4.3
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [lm-sensors] [PATCH] hwmon: Add LTC4245 driver
2008-10-20 16:03 [lm-sensors] [PATCH] hwmon: Add LTC4245 driver Ira Snyder
` (4 preceding siblings ...)
2008-10-21 17:44 ` Ira Snyder
@ 2008-10-22 7:21 ` Jean Delvare
2008-10-22 23:21 ` Ira Snyder
2008-10-23 8:34 ` Jean Delvare
7 siblings, 0 replies; 9+ messages in thread
From: Jean Delvare @ 2008-10-22 7:21 UTC (permalink / raw)
To: lm-sensors
Hi Ira,
On Tue, 21 Oct 2008 10:44:18 -0700, Ira Snyder wrote:
> 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>
> ---
>
> This should be the final revision of the driver. For real this time :)
>
> Jean, please feel free to just delete the "#if 0" block if you feel it
> shouldn't be there. The comment is just fine.
>
> Changes v4 -> v5:
> * rename the variable "current" to "curr" to workaround brokenness
> in asm/current.h on x86, powerpc64, etc.
> * check for errors when reading from i2c
> * disable probing, add example usage of force param to documentation
> * add missing #include <linux/kernel.h>
> * use i2c_smbus_read_byte_data() rather than ltc4245_read_reg()
> * const-ify some variables
>
> Changes v3 -> v4:
> * simplify ltc4245_get_voltage(), removing special casing for -12v
> * power should always be a positive value
>
> Changes v2 -> v3:
> * fix units (power?_input in uW, curr?_input in mA)
> * combine all alarm functions
> * rename power[1-4]_alarm to in[5-8]_min_alarm, per suggestions
>
> Changes v1 -> v2:
> * fixed checkpatch warnings
> * removed raw register access, per suggestions
> * changed sysfs interface, per suggestions (current, power, alarms)
>
>
> Documentation/hwmon/ltc4245 | 81 ++++++
> drivers/hwmon/Kconfig | 11 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/ltc4245.c | 578 +++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 671 insertions(+), 0 deletions(-)
> create mode 100644 Documentation/hwmon/ltc4245
> create mode 100644 drivers/hwmon/ltc4245.c
I'm fine with all changes except:
> --- /dev/null
> +++ b/Documentation/hwmon/ltc4245
> (...)
> +Usage Notes
> +-------------
2 dashes too many.
> (...)
> +struct ltc4245_data {
> + struct device *hwmon_dev;
> +
> + struct mutex update_lock;
> + bool valid;
> + unsigned long last_updated; /* in jiffies */
> +
> + /* Control registers */
> + s32 cregs[0x08];
> +
> + /* Voltage registers */
> + s32 vregs[0x0f];
> +};
You changed these arrays from u8 to s32. This makes your data structure
much larger. It would make some sense if you meant to store error
values in order to process them later and report them as such to the
user. However...
> (...)
> +static int ltc4245_get_voltage(struct device *dev, u8 reg)
> +{
> + struct ltc4245_data *data = ltc4245_update_device(dev);
> + const s32 val = data->vregs[reg - 0x10];
> + const u8 regval = val;
> + u32 voltage = 0;
> +
> + if (unlikely(val < 0))
> + return 0;
All you do in case of error is return 0, that is, exactly as if the
register contained 0. So in the end you're not really handling the
error.
If you don't handle the error then it's much cheaper memory-wise to
turn errors into 0 as soon as you read the value from the register in
ltc4245_update_device() so that you can use arrays of u8 in your data
structure.
If you do want to handle the error (most drivers don't) then you have
to transmit the error code up all the way to the sysfs callback
function. This implies changing the prototype of your
ltc4245_get_voltage() function so that it can return both the error
value and the voltage value.
As a summary, please either handle the errors completely or don't
handle them at all. Doing it half way makes the driver bigger with no
benefit.
> (...)
> +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;
> + if (v < 0)
> + return -ENODEV;
This test and return were supposed to be removed, weren't they?
> +
> + 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;
> +}
All the rest looks alright to me now. I'll do some tests with
lm-sensors now to test the sysfs interface.
--
Jean Delvare
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply [flat|nested] 9+ messages in thread
* [lm-sensors] [PATCH] hwmon: Add LTC4245 driver
2008-10-20 16:03 [lm-sensors] [PATCH] hwmon: Add LTC4245 driver Ira Snyder
` (5 preceding siblings ...)
2008-10-22 7:21 ` Jean Delvare
@ 2008-10-22 23:21 ` Ira Snyder
2008-10-23 8:34 ` Jean Delvare
7 siblings, 0 replies; 9+ messages in thread
From: Ira Snyder @ 2008-10-22 23:21 UTC (permalink / raw)
To: lm-sensors
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>
---
Yet another revision of the ltc4245 driver. :)
Changes v5 -> v6:
* handle errors consistently
Changes v4 -> v5:
* rename the variable "current" to "curr" to workaround brokenness
in asm/current.h on x86, powerpc64, etc.
* check for errors when reading from i2c
* disable probing, add example usage of force param to documentation
* add missing #include <linux/kernel.h>
* use i2c_smbus_read_byte_data() rather than ltc4245_read_reg()
* const-ify some variables
Changes v3 -> v4:
* simplify ltc4245_get_voltage(), removing special casing for -12v
* power should always be a positive value
Changes v2 -> v3:
* fix units (power?_input in uW, curr?_input in mA)
* combine all alarm functions
* rename power[1-4]_alarm to in[5-8]_min_alarm, per suggestions
Changes v1 -> v2:
* fixed checkpatch warnings
* removed raw register access, per suggestions
* changed sysfs interface, per suggestions (current, power, alarms)
Documentation/hwmon/ltc4245 | 81 ++++++
drivers/hwmon/Kconfig | 11 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/ltc4245.c | 567 +++++++++++++++++++++++++++++++++++++++++++
4 files changed, 660 insertions(+), 0 deletions(-)
create mode 100644 Documentation/hwmon/ltc4245
create mode 100644 drivers/hwmon/ltc4245.c
diff --git a/Documentation/hwmon/ltc4245 b/Documentation/hwmon/ltc4245
new file mode 100644
index 0000000..bae7a3a
--- /dev/null
+++ b/Documentation/hwmon/ltc4245
@@ -0,0 +1,81 @@
+Kernel driver ltc4245
+==========+
+Supported chips:
+ * Linear Technology LTC4245
+ Prefix: 'ltc4245'
+ Addresses scanned: 0x20-0x3f
+ Datasheet:
+ http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
+
+Author: Ira W. Snyder <iws@ovro.caltech.edu>
+
+
+Description
+-----------
+
+The LTC4245 controller allows a board to be safely inserted and removed
+from a live backplane in multiple supply systems such as CompactPCI and
+PCI Express.
+
+
+Usage Notes
+-----------
+
+This driver does not probe for LTC4245 devices, due to the fact that some
+of the possible addresses are unfriendly to probing. You will need to use
+the "force" parameter to tell the driver where to find the device.
+
+Example: the following will load the driver for an LTC4245 at address 0x23
+on I2C bus #1:
+$ modprobe ltc4245 force=1,0x23
+
+
+Sysfs entries
+-------------
+
+The LTC4245 has built-in limits for over and under current warnings. This
+makes it very likely that the reference circuit will be used.
+
+This driver uses the values in the datasheet to change the register values
+into the values specified in the sysfs-interface document. The current readings
+rely on the sense resistors listed in Table 2: "Sense Resistor Values".
+
+in1_input 12v input voltage (mV)
+in2_input 5v input voltage (mV)
+in3_input 3v input voltage (mV)
+in4_input Vee (-12v) input voltage (mV)
+
+in1_min_alarm 12v input undervoltage alarm
+in2_min_alarm 5v input undervoltage alarm
+in3_min_alarm 3v input undervoltage alarm
+in4_min_alarm Vee (-12v) input undervoltage alarm
+
+curr1_input 12v current (mA)
+curr2_input 5v current (mA)
+curr3_input 3v current (mA)
+curr4_input Vee (-12v) current (mA)
+
+curr1_max_alarm 12v overcurrent alarm
+curr2_max_alarm 5v overcurrent alarm
+curr3_max_alarm 3v overcurrent alarm
+curr4_max_alarm Vee (-12v) overcurrent alarm
+
+in5_input 12v output voltage (mV)
+in6_input 5v output voltage (mV)
+in7_input 3v output voltage (mV)
+in8_input Vee (-12v) output voltage (mV)
+
+in5_min_alarm 12v output undervoltage alarm
+in6_min_alarm 5v output undervoltage alarm
+in7_min_alarm 3v output undervoltage alarm
+in8_min_alarm Vee (-12v) output undervoltage alarm
+
+in9_input GPIO #1 voltage data
+in10_input GPIO #2 voltage data
+in11_input GPIO #3 voltage data
+
+power1_input 12v power usage (mW)
+power2_input 5v power usage (mW)
+power3_input 3v power usage (mW)
+power4_input Vee (-12v) power usage (mW)
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 6de1e0f..416f620 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -850,6 +850,17 @@ config SENSORS_APPLESMC
Say Y here if you have an applicable laptop and want to experience
the awesome power of applesmc.
+config SENSORS_LTC4245
+ tristate "Linear Technology LTC4245"
+ depends on I2C && EXPERIMENTAL
+ default n
+ help
+ If you say yes here you get support for Linear Technology LTC4245
+ Multiple Supply Hot Swap Controller I2C interface.
+
+ This driver can also be built as a module. If so, the module will
+ be called ltc4245.
+
config HWMON_DEBUG_CHIP
bool "Hardware Monitoring Chip debugging messages"
default n
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 042d5a7..8f2f412 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -60,6 +60,7 @@ obj-$(CONFIG_SENSORS_LM87) += lm87.o
obj-$(CONFIG_SENSORS_LM90) += lm90.o
obj-$(CONFIG_SENSORS_LM92) += lm92.o
obj-$(CONFIG_SENSORS_LM93) += lm93.o
+obj-$(CONFIG_SENSORS_LTC4245) += ltc4245.o
obj-$(CONFIG_SENSORS_MAX1111) += max1111.o
obj-$(CONFIG_SENSORS_MAX1619) += max1619.o
obj-$(CONFIG_SENSORS_MAX6650) += max6650.o
diff --git a/drivers/hwmon/ltc4245.c b/drivers/hwmon/ltc4245.c
new file mode 100644
index 0000000..034b2c5
--- /dev/null
+++ b/drivers/hwmon/ltc4245.c
@@ -0,0 +1,567 @@
+/*
+ * Driver for Linear Technology LTC4245 I2C Multiple Supply Hot Swap Controller
+ *
+ * Copyright (C) 2008 Ira W. Snyder <iws@ovro.caltech.edu>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This driver is based on the ds1621 and ina209 drivers.
+ *
+ * Datasheet:
+ * http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1140,P19392,D13517
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+/* Valid addresses are 0x20 - 0x3f
+ *
+ * For now, we do not probe, since some of these addresses
+ * are known to be unfriendly to probing */
+static const unsigned short normal_i2c[] = { I2C_CLIENT_END };
+
+/* Insmod parameters */
+I2C_CLIENT_INSMOD_1(ltc4245);
+
+/* Here are names of the chip's registers (a.k.a. commands) */
+enum ltc4245_cmd {
+ LTC4245_STATUS = 0x00, /* readonly */
+ LTC4245_ALERT = 0x01,
+ LTC4245_CONTROL = 0x02,
+ LTC4245_ON = 0x03,
+ LTC4245_FAULT1 = 0x04,
+ LTC4245_FAULT2 = 0x05,
+ LTC4245_GPIO = 0x06,
+ LTC4245_ADCADR = 0x07,
+
+ LTC4245_12VIN = 0x10,
+ LTC4245_12VSENSE = 0x11,
+ LTC4245_12VOUT = 0x12,
+ LTC4245_5VIN = 0x13,
+ LTC4245_5VSENSE = 0x14,
+ LTC4245_5VOUT = 0x15,
+ LTC4245_3VIN = 0x16,
+ LTC4245_3VSENSE = 0x17,
+ LTC4245_3VOUT = 0x18,
+ LTC4245_VEEIN = 0x19,
+ LTC4245_VEESENSE = 0x1a,
+ LTC4245_VEEOUT = 0x1b,
+ LTC4245_GPIOADC1 = 0x1c,
+ LTC4245_GPIOADC2 = 0x1d,
+ LTC4245_GPIOADC3 = 0x1e,
+};
+
+struct ltc4245_data {
+ struct device *hwmon_dev;
+
+ struct mutex update_lock;
+ bool valid;
+ unsigned long last_updated; /* in jiffies */
+
+ /* Control registers */
+ u8 cregs[0x08];
+
+ /* Voltage registers */
+ u8 vregs[0x0f];
+};
+
+static struct ltc4245_data *ltc4245_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ltc4245_data *data = i2c_get_clientdata(client);
+ s32 val;
+ int i;
+
+ mutex_lock(&data->update_lock);
+
+ if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+
+ dev_dbg(&client->dev, "Starting ltc4245 update\n");
+
+ /* Read control registers -- 0x00 to 0x07 */
+ for (i = 0; i < ARRAY_SIZE(data->cregs); i++) {
+ val = i2c_smbus_read_byte_data(client, i);
+ if (unlikely(val < 0))
+ data->cregs[i] = 0;
+ else
+ data->cregs[i] = val;
+ }
+
+ /* Read voltage registers -- 0x10 to 0x1f */
+ for (i = 0; i < ARRAY_SIZE(data->vregs); i++) {
+ val = i2c_smbus_read_byte_data(client, i+0x10);
+ if (unlikely(val < 0))
+ data->vregs[i] = 0;
+ else
+ data->vregs[i] = val;
+ }
+
+ data->last_updated = jiffies;
+ data->valid = 1;
+ }
+
+ mutex_unlock(&data->update_lock);
+
+ return data;
+}
+
+/* Return the voltage from the given register in millivolts */
+static int ltc4245_get_voltage(struct device *dev, u8 reg)
+{
+ struct ltc4245_data *data = ltc4245_update_device(dev);
+ const u8 regval = data->vregs[reg - 0x10];
+ u32 voltage = 0;
+
+ switch (reg) {
+ case LTC4245_12VIN:
+ case LTC4245_12VOUT:
+ voltage = regval * 55;
+ break;
+ case LTC4245_5VIN:
+ case LTC4245_5VOUT:
+ voltage = regval * 22;
+ break;
+ case LTC4245_3VIN:
+ case LTC4245_3VOUT:
+ voltage = regval * 15;
+ break;
+ case LTC4245_VEEIN:
+ case LTC4245_VEEOUT:
+ voltage = regval * -55;
+ break;
+ case LTC4245_GPIOADC1:
+ case LTC4245_GPIOADC2:
+ case LTC4245_GPIOADC3:
+ voltage = regval * 10;
+ break;
+ default:
+ /* If we get here, the developer messed up */
+ WARN_ON_ONCE(1);
+ break;
+ }
+
+ return voltage;
+}
+
+/* Return the current in the given sense register in milliAmperes */
+static unsigned int ltc4245_get_current(struct device *dev, u8 reg)
+{
+ struct ltc4245_data *data = ltc4245_update_device(dev);
+ const u8 regval = data->vregs[reg - 0x10];
+ unsigned int voltage;
+ unsigned int curr;
+
+ /* The strange looking conversions that follow are fixed-point
+ * math, since we cannot do floating point in the kernel.
+ *
+ * Step 1: convert sense register to microVolts
+ * Step 2: convert voltage to milliAmperes
+ *
+ * If you play around with the V=IR equation, you come up with
+ * the following: X uV / Y mOhm = Z mA
+ *
+ * With the resistors that are fractions of a milliOhm, we multiply
+ * the voltage and resistance by 10, to shift the decimal point.
+ * Now we can use the normal division operator again.
+ */
+
+ switch (reg) {
+ case LTC4245_12VSENSE:
+ voltage = regval * 250; /* voltage in uV */
+ curr = voltage / 50; /* sense resistor 50 mOhm */
+ break;
+ case LTC4245_5VSENSE:
+ voltage = regval * 125; /* voltage in uV */
+ curr = (voltage * 10) / 35; /* sense resistor 3.5 mOhm */
+ break;
+ case LTC4245_3VSENSE:
+ voltage = regval * 125; /* voltage in uV */
+ curr = (voltage * 10) / 25; /* sense resistor 2.5 mOhm */
+ break;
+ case LTC4245_VEESENSE:
+ voltage = regval * 250; /* voltage in uV */
+ curr = voltage / 100; /* sense resistor 100 mOhm */
+ break;
+ default:
+ /* If we get here, the developer messed up */
+ WARN_ON_ONCE(1);
+ curr = 0;
+ break;
+ }
+
+ return curr;
+}
+
+static ssize_t ltc4245_show_voltage(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const int voltage = ltc4245_get_voltage(dev, attr->index);
+
+ return snprintf(buf, PAGE_SIZE, "%d\n", voltage);
+}
+
+static ssize_t ltc4245_show_current(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const unsigned int curr = ltc4245_get_current(dev, attr->index);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", curr);
+}
+
+static ssize_t ltc4245_show_power(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ const unsigned int curr = ltc4245_get_current(dev, attr->index);
+ const int output_voltage = ltc4245_get_voltage(dev, attr->index+1);
+
+ /* current in mA * voltage in mV = power in uW */
+ const unsigned int power = abs(output_voltage * curr);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", power);
+}
+
+static ssize_t ltc4245_show_alarm(struct device *dev,
+ struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
+ struct ltc4245_data *data = ltc4245_update_device(dev);
+ const u8 reg = data->cregs[attr->index];
+ const u32 mask = attr->nr;
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", (reg & mask) ? 1 : 0);
+}
+
+/* These macros are used below in constructing device attribute objects
+ * for use with sysfs_create_group() to make a sysfs device file
+ * for each register.
+ */
+
+#define LTC4245_VOLTAGE(name, ltc4245_cmd_idx) \
+ static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+ ltc4245_show_voltage, NULL, ltc4245_cmd_idx)
+
+#define LTC4245_CURRENT(name, ltc4245_cmd_idx) \
+ static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+ ltc4245_show_current, NULL, ltc4245_cmd_idx)
+
+#define LTC4245_POWER(name, ltc4245_cmd_idx) \
+ static SENSOR_DEVICE_ATTR(name, S_IRUGO, \
+ ltc4245_show_power, NULL, ltc4245_cmd_idx)
+
+#define LTC4245_ALARM(name, mask, reg) \
+ static SENSOR_DEVICE_ATTR_2(name, S_IRUGO, \
+ ltc4245_show_alarm, NULL, (mask), reg)
+
+/* Construct a sensor_device_attribute structure for each register */
+
+/* Input voltages */
+LTC4245_VOLTAGE(in1_input, LTC4245_12VIN);
+LTC4245_VOLTAGE(in2_input, LTC4245_5VIN);
+LTC4245_VOLTAGE(in3_input, LTC4245_3VIN);
+LTC4245_VOLTAGE(in4_input, LTC4245_VEEIN);
+
+/* Input undervoltage alarms */
+LTC4245_ALARM(in1_min_alarm, (1 << 0), LTC4245_FAULT1);
+LTC4245_ALARM(in2_min_alarm, (1 << 1), LTC4245_FAULT1);
+LTC4245_ALARM(in3_min_alarm, (1 << 2), LTC4245_FAULT1);
+LTC4245_ALARM(in4_min_alarm, (1 << 3), LTC4245_FAULT1);
+
+/* Currents (via sense resistor) */
+LTC4245_CURRENT(curr1_input, LTC4245_12VSENSE);
+LTC4245_CURRENT(curr2_input, LTC4245_5VSENSE);
+LTC4245_CURRENT(curr3_input, LTC4245_3VSENSE);
+LTC4245_CURRENT(curr4_input, LTC4245_VEESENSE);
+
+/* Overcurrent alarms */
+LTC4245_ALARM(curr1_max_alarm, (1 << 4), LTC4245_FAULT1);
+LTC4245_ALARM(curr2_max_alarm, (1 << 5), LTC4245_FAULT1);
+LTC4245_ALARM(curr3_max_alarm, (1 << 6), LTC4245_FAULT1);
+LTC4245_ALARM(curr4_max_alarm, (1 << 7), LTC4245_FAULT1);
+
+/* Output voltages */
+LTC4245_VOLTAGE(in5_input, LTC4245_12VOUT);
+LTC4245_VOLTAGE(in6_input, LTC4245_5VOUT);
+LTC4245_VOLTAGE(in7_input, LTC4245_3VOUT);
+LTC4245_VOLTAGE(in8_input, LTC4245_VEEOUT);
+
+/* Power Bad alarms */
+LTC4245_ALARM(in5_min_alarm, (1 << 0), LTC4245_FAULT2);
+LTC4245_ALARM(in6_min_alarm, (1 << 1), LTC4245_FAULT2);
+LTC4245_ALARM(in7_min_alarm, (1 << 2), LTC4245_FAULT2);
+LTC4245_ALARM(in8_min_alarm, (1 << 3), LTC4245_FAULT2);
+
+/* GPIO voltages */
+LTC4245_VOLTAGE(in9_input, LTC4245_GPIOADC1);
+LTC4245_VOLTAGE(in10_input, LTC4245_GPIOADC2);
+LTC4245_VOLTAGE(in11_input, LTC4245_GPIOADC3);
+
+/* Power Consumption (virtual) */
+LTC4245_POWER(power1_input, LTC4245_12VSENSE);
+LTC4245_POWER(power2_input, LTC4245_5VSENSE);
+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);
--
1.5.4.3
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [lm-sensors] [PATCH] hwmon: Add LTC4245 driver
2008-10-20 16:03 [lm-sensors] [PATCH] hwmon: Add LTC4245 driver Ira Snyder
` (6 preceding siblings ...)
2008-10-22 23:21 ` Ira Snyder
@ 2008-10-23 8:34 ` Jean Delvare
7 siblings, 0 replies; 9+ messages in thread
From: Jean Delvare @ 2008-10-23 8:34 UTC (permalink / raw)
To: lm-sensors
On Wed, 22 Oct 2008 16:21:29 -0700, Ira Snyder wrote:
> 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>
> ---
>
> Yet another revision of the ltc4245 driver. :)
>
> Changes v5 -> v6:
> * handle errors consistently
>
> Changes v4 -> v5:
> * rename the variable "current" to "curr" to workaround brokenness
> in asm/current.h on x86, powerpc64, etc.
> * check for errors when reading from i2c
> * disable probing, add example usage of force param to documentation
> * add missing #include <linux/kernel.h>
> * use i2c_smbus_read_byte_data() rather than ltc4245_read_reg()
> * const-ify some variables
>
> Changes v3 -> v4:
> * simplify ltc4245_get_voltage(), removing special casing for -12v
> * power should always be a positive value
>
> Changes v2 -> v3:
> * fix units (power?_input in uW, curr?_input in mA)
> * combine all alarm functions
> * rename power[1-4]_alarm to in[5-8]_min_alarm, per suggestions
>
> Changes v1 -> v2:
> * fixed checkpatch warnings
> * removed raw register access, per suggestions
> * changed sysfs interface, per suggestions (current, power, alarms)
>
> Documentation/hwmon/ltc4245 | 81 ++++++
> drivers/hwmon/Kconfig | 11 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/ltc4245.c | 567 +++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 660 insertions(+), 0 deletions(-)
> create mode 100644 Documentation/hwmon/ltc4245
> create mode 100644 drivers/hwmon/ltc4245.c
Applied, thanks :)
--
Jean Delvare
_______________________________________________
lm-sensors mailing list
lm-sensors@lm-sensors.org
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2008-10-23 8:34 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2008-10-20 16:03 [lm-sensors] [PATCH] hwmon: Add LTC4245 driver Ira Snyder
2008-10-20 17:29 ` Hans de Goede
2008-10-21 12:19 ` Jean Delvare
2008-10-21 12:27 ` Jean Delvare
2008-10-21 12:50 ` Jean Delvare
2008-10-21 17:44 ` Ira Snyder
2008-10-22 7:21 ` Jean Delvare
2008-10-22 23:21 ` Ira Snyder
2008-10-23 8:34 ` Jean Delvare
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.