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-rw-r--r--Documentation/hwmon/lineage-pem77
-rw-r--r--drivers/hwmon/Kconfig11
-rw-r--r--drivers/hwmon/Makefile1
-rw-r--r--drivers/hwmon/lineage-pem.c589
4 files changed, 678 insertions, 0 deletions
diff --git a/Documentation/hwmon/lineage-pem b/Documentation/hwmon/lineage-pem
new file mode 100644
index 00000000000..2ba5ed12685
--- /dev/null
+++ b/Documentation/hwmon/lineage-pem
@@ -0,0 +1,77 @@
+Kernel driver lineage-pem
+=========================
+
+Supported devices:
+ * Lineage Compact Power Line Power Entry Modules
+ Prefix: 'lineage-pem'
+ Addresses scanned: -
+ Documentation:
+ http://www.lineagepower.com/oem/pdf/CPLI2C.pdf
+
+Author: Guenter Roeck <guenter.roeck@ericsson.com>
+
+
+Description
+-----------
+
+This driver supports various Lineage Compact Power Line DC/DC and AC/DC
+converters such as CP1800, CP2000AC, CP2000DC, CP2100DC, and others.
+
+Lineage CPL power entry modules are nominally PMBus compliant. However, most
+standard PMBus commands are not supported. Specifically, all hardware monitoring
+and status reporting commands are non-standard. For this reason, a standard
+PMBus driver can not be used.
+
+
+Usage Notes
+-----------
+
+This driver does not probe for Lineage CPL devices, since there is no register
+which can be safely used to identify the chip. You will have to instantiate
+the devices explicitly.
+
+Example: the following will load the driver for a Lineage PEM at address 0x40
+on I2C bus #1:
+$ modprobe lineage-pem
+$ echo lineage-pem 0x40 > /sys/bus/i2c/devices/i2c-1/new_device
+
+All Lineage CPL power entry modules have a built-in I2C bus master selector
+(PCA9541). To ensure device access, this driver should only be used as client
+driver to the pca9541 I2C master selector driver.
+
+
+Sysfs entries
+-------------
+
+All Lineage CPL devices report output voltage and device temperature as well as
+alarms for output voltage, temperature, input voltage, input current, input power,
+and fan status.
+
+Input voltage, input current, input power, and fan speed measurement is only
+supported on newer devices. The driver detects if those attributes are supported,
+and only creates respective sysfs entries if they are.
+
+in1_input Output voltage (mV)
+in1_min_alarm Output undervoltage alarm
+in1_max_alarm Output overvoltage alarm
+in1_crit Output voltage critical alarm
+
+in2_input Input voltage (mV, optional)
+in2_alarm Input voltage alarm
+
+curr1_input Input current (mA, optional)
+curr1_alarm Input overcurrent alarm
+
+power1_input Input power (uW, optional)
+power1_alarm Input power alarm
+
+fan1_input Fan 1 speed (rpm, optional)
+fan2_input Fan 2 speed (rpm, optional)
+fan3_input Fan 3 speed (rpm, optional)
+
+temp1_input
+temp1_max
+temp1_crit
+temp1_alarm
+temp1_crit_alarm
+temp1_fault
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 3bd993b0a3c..d4ffc605208 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -467,6 +467,17 @@ config SENSORS_JC42
This driver can also be built as a module. If so, the module
will be called jc42.
+config SENSORS_LINEAGE
+ tristate "Lineage Compact Power Line Power Entry Module"
+ depends on I2C && EXPERIMENTAL
+ help
+ If you say yes here you get support for the Lineage Compact Power Line
+ series of DC/DC and AC/DC converters such as CP1800, CP2000AC,
+ CP2000DC, CP2725, and others.
+
+ This driver can also be built as a module. If so, the module
+ will be called lineage-pem.
+
config SENSORS_LM63
tristate "National Semiconductor LM63 and LM64"
depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index f69783150b7..46819818ef5 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_SENSORS_JC42) += jc42.o
obj-$(CONFIG_SENSORS_JZ4740) += jz4740-hwmon.o
obj-$(CONFIG_SENSORS_K8TEMP) += k8temp.o
obj-$(CONFIG_SENSORS_K10TEMP) += k10temp.o
+obj-$(CONFIG_SENSORS_LINEAGE) += lineage-pem.o
obj-$(CONFIG_SENSORS_LIS3LV02D) += lis3lv02d.o hp_accel.o
obj-$(CONFIG_SENSORS_LIS3_SPI) += lis3lv02d.o lis3lv02d_spi.o
obj-$(CONFIG_SENSORS_LIS3_I2C) += lis3lv02d.o lis3lv02d_i2c.o
diff --git a/drivers/hwmon/lineage-pem.c b/drivers/hwmon/lineage-pem.c
new file mode 100644
index 00000000000..d39ee24e52f
--- /dev/null
+++ b/drivers/hwmon/lineage-pem.c
@@ -0,0 +1,589 @@
+/*
+ * Driver for Lineage Compact Power Line series of power entry modules.
+ *
+ * Copyright (C) 2010, 2011 Ericsson AB.
+ *
+ * Documentation:
+ * http://www.lineagepower.com/oem/pdf/CPLI2C.pdf
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#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>
+
+/*
+ * This driver supports various Lineage Compact Power Line DC/DC and AC/DC
+ * converters such as CP1800, CP2000AC, CP2000DC, CP2100DC, and others.
+ *
+ * The devices are nominally PMBus compliant. However, most standard PMBus
+ * commands are not supported. Specifically, all hardware monitoring and
+ * status reporting commands are non-standard. For this reason, a standard
+ * PMBus driver can not be used.
+ *
+ * All Lineage CPL devices have a built-in I2C bus master selector (PCA9541).
+ * To ensure device access, this driver should only be used as client driver
+ * to the pca9541 I2C master selector driver.
+ */
+
+/* Command codes */
+#define PEM_OPERATION 0x01
+#define PEM_CLEAR_INFO_FLAGS 0x03
+#define PEM_VOUT_COMMAND 0x21
+#define PEM_VOUT_OV_FAULT_LIMIT 0x40
+#define PEM_READ_DATA_STRING 0xd0
+#define PEM_READ_INPUT_STRING 0xdc
+#define PEM_READ_FIRMWARE_REV 0xdd
+#define PEM_READ_RUN_TIMER 0xde
+#define PEM_FAN_HI_SPEED 0xdf
+#define PEM_FAN_NORMAL_SPEED 0xe0
+#define PEM_READ_FAN_SPEED 0xe1
+
+/* offsets in data string */
+#define PEM_DATA_STATUS_2 0
+#define PEM_DATA_STATUS_1 1
+#define PEM_DATA_ALARM_2 2
+#define PEM_DATA_ALARM_1 3
+#define PEM_DATA_VOUT_LSB 4
+#define PEM_DATA_VOUT_MSB 5
+#define PEM_DATA_CURRENT 6
+#define PEM_DATA_TEMP 7
+
+/* Virtual entries, to report constants */
+#define PEM_DATA_TEMP_MAX 10
+#define PEM_DATA_TEMP_CRIT 11
+
+/* offsets in input string */
+#define PEM_INPUT_VOLTAGE 0
+#define PEM_INPUT_POWER_LSB 1
+#define PEM_INPUT_POWER_MSB 2
+
+/* offsets in fan data */
+#define PEM_FAN_ADJUSTMENT 0
+#define PEM_FAN_FAN1 1
+#define PEM_FAN_FAN2 2
+#define PEM_FAN_FAN3 3
+
+/* Status register bits */
+#define STS1_OUTPUT_ON (1 << 0)
+#define STS1_LEDS_FLASHING (1 << 1)
+#define STS1_EXT_FAULT (1 << 2)
+#define STS1_SERVICE_LED_ON (1 << 3)
+#define STS1_SHUTDOWN_OCCURRED (1 << 4)
+#define STS1_INT_FAULT (1 << 5)
+#define STS1_ISOLATION_TEST_OK (1 << 6)
+
+#define STS2_ENABLE_PIN_HI (1 << 0)
+#define STS2_DATA_OUT_RANGE (1 << 1)
+#define STS2_RESTARTED_OK (1 << 1)
+#define STS2_ISOLATION_TEST_FAIL (1 << 3)
+#define STS2_HIGH_POWER_CAP (1 << 4)
+#define STS2_INVALID_INSTR (1 << 5)
+#define STS2_WILL_RESTART (1 << 6)
+#define STS2_PEC_ERR (1 << 7)
+
+/* Alarm register bits */
+#define ALRM1_VIN_OUT_LIMIT (1 << 0)
+#define ALRM1_VOUT_OUT_LIMIT (1 << 1)
+#define ALRM1_OV_VOLT_SHUTDOWN (1 << 2)
+#define ALRM1_VIN_OVERCURRENT (1 << 3)
+#define ALRM1_TEMP_WARNING (1 << 4)
+#define ALRM1_TEMP_SHUTDOWN (1 << 5)
+#define ALRM1_PRIMARY_FAULT (1 << 6)
+#define ALRM1_POWER_LIMIT (1 << 7)
+
+#define ALRM2_5V_OUT_LIMIT (1 << 1)
+#define ALRM2_TEMP_FAULT (1 << 2)
+#define ALRM2_OV_LOW (1 << 3)
+#define ALRM2_DCDC_TEMP_HIGH (1 << 4)
+#define ALRM2_PRI_TEMP_HIGH (1 << 5)
+#define ALRM2_NO_PRIMARY (1 << 6)
+#define ALRM2_FAN_FAULT (1 << 7)
+
+#define FIRMWARE_REV_LEN 4
+#define DATA_STRING_LEN 9
+#define INPUT_STRING_LEN 5 /* 4 for most devices */
+#define FAN_SPEED_LEN 5
+
+struct pem_data {
+ struct device *hwmon_dev;
+
+ struct mutex update_lock;
+ bool valid;
+ bool fans_supported;
+ int input_length;
+ unsigned long last_updated; /* in jiffies */
+
+ u8 firmware_rev[FIRMWARE_REV_LEN];
+ u8 data_string[DATA_STRING_LEN];
+ u8 input_string[INPUT_STRING_LEN];
+ u8 fan_speed[FAN_SPEED_LEN];
+};
+
+static int pem_read_block(struct i2c_client *client, u8 command, u8 *data,
+ int data_len)
+{
+ u8 block_buffer[I2C_SMBUS_BLOCK_MAX];
+ int result;
+
+ result = i2c_smbus_read_block_data(client, command, block_buffer);
+ if (unlikely(result < 0))
+ goto abort;
+ if (unlikely(result == 0xff || result != data_len)) {
+ result = -EIO;
+ goto abort;
+ }
+ memcpy(data, block_buffer, data_len);
+ result = 0;
+abort:
+ return result;
+}
+
+static struct pem_data *pem_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct pem_data *data = i2c_get_clientdata(client);
+ struct pem_data *ret = data;
+
+ mutex_lock(&data->update_lock);
+
+ if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+ int result;
+
+ /* Read data string */
+ result = pem_read_block(client, PEM_READ_DATA_STRING,
+ data->data_string,
+ sizeof(data->data_string));
+ if (unlikely(result < 0)) {
+ ret = ERR_PTR(result);
+ goto abort;
+ }
+
+ /* Read input string */
+ if (data->input_length) {
+ result = pem_read_block(client, PEM_READ_INPUT_STRING,
+ data->input_string,
+ data->input_length);
+ if (unlikely(result < 0)) {
+ ret = ERR_PTR(result);
+ goto abort;
+ }
+ }
+
+ /* Read fan speeds */
+ if (data->fans_supported) {
+ result = pem_read_block(client, PEM_READ_FAN_SPEED,
+ data->fan_speed,
+ sizeof(data->fan_speed));
+ if (unlikely(result < 0)) {
+ ret = ERR_PTR(result);
+ goto abort;
+ }
+ }
+
+ i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
+
+ data->last_updated = jiffies;
+ data->valid = 1;
+ }
+abort:
+ mutex_unlock(&data->update_lock);
+ return ret;
+}
+
+static long pem_get_data(u8 *data, int len, int index)
+{
+ long val;
+
+ switch (index) {
+ case PEM_DATA_VOUT_LSB:
+ val = (data[index] + (data[index+1] << 8)) * 5 / 2;
+ break;
+ case PEM_DATA_CURRENT:
+ val = data[index] * 200;
+ break;
+ case PEM_DATA_TEMP:
+ val = data[index] * 1000;
+ break;
+ case PEM_DATA_TEMP_MAX:
+ val = 97 * 1000; /* 97 degrees C per datasheet */
+ break;
+ case PEM_DATA_TEMP_CRIT:
+ val = 107 * 1000; /* 107 degrees C per datasheet */
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ val = 0;
+ }
+ return val;
+}
+
+static long pem_get_input(u8 *data, int len, int index)
+{
+ long val;
+
+ switch (index) {
+ case PEM_INPUT_VOLTAGE:
+ if (len == INPUT_STRING_LEN)
+ val = (data[index] + (data[index+1] << 8) - 75) * 1000;
+ else
+ val = (data[index] - 75) * 1000;
+ break;
+ case PEM_INPUT_POWER_LSB:
+ if (len == INPUT_STRING_LEN)
+ index++;
+ val = (data[index] + (data[index+1] << 8)) * 1000000L;
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ val = 0;
+ }
+ return val;
+}
+
+static long pem_get_fan(u8 *data, int len, int index)
+{
+ long val;
+
+ switch (index) {
+ case PEM_FAN_FAN1:
+ case PEM_FAN_FAN2:
+ case PEM_FAN_FAN3:
+ val = data[index] * 100;
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ val = 0;
+ }
+ return val;
+}
+
+/*
+ * Show boolean, either a fault or an alarm.
+ * .nr points to the register, .index is the bit mask to check
+ */
+static ssize_t pem_show_bool(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
+ struct pem_data *data = pem_update_device(dev);
+ u8 status;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ status = data->data_string[attr->nr] & attr->index;
+ return snprintf(buf, PAGE_SIZE, "%d\n", !!status);
+}
+
+static ssize_t pem_show_data(struct device *dev, struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct pem_data *data = pem_update_device(dev);
+ long value;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ value = pem_get_data(data->data_string, sizeof(data->data_string),
+ attr->index);
+
+ return snprintf(buf, PAGE_SIZE, "%ld\n", value);
+}
+
+static ssize_t pem_show_input(struct device *dev, struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct pem_data *data = pem_update_device(dev);
+ long value;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ value = pem_get_input(data->input_string, sizeof(data->input_string),
+ attr->index);
+
+ return snprintf(buf, PAGE_SIZE, "%ld\n", value);
+}
+
+static ssize_t pem_show_fan(struct device *dev, struct device_attribute *da,
+ char *buf)
+{
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ struct pem_data *data = pem_update_device(dev);
+ long value;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ value = pem_get_fan(data->fan_speed, sizeof(data->fan_speed),
+ attr->index);
+
+ return snprintf(buf, PAGE_SIZE, "%ld\n", value);
+}
+
+/* Voltages */
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, pem_show_data, NULL,
+ PEM_DATA_VOUT_LSB);
+static SENSOR_DEVICE_ATTR_2(in1_min_alarm, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_2, ALRM2_OV_LOW);
+static SENSOR_DEVICE_ATTR_2(in1_max_alarm, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_1, ALRM1_VOUT_OUT_LIMIT);
+static SENSOR_DEVICE_ATTR_2(in1_crit_alarm, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_1, ALRM1_OV_VOLT_SHUTDOWN);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, pem_show_input, NULL,
+ PEM_INPUT_VOLTAGE);
+static SENSOR_DEVICE_ATTR_2(in2_alarm, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_1,
+ ALRM1_VIN_OUT_LIMIT | ALRM1_PRIMARY_FAULT);
+
+/* Currents */
+static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, pem_show_data, NULL,
+ PEM_DATA_CURRENT);
+static SENSOR_DEVICE_ATTR_2(curr1_alarm, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_1, ALRM1_VIN_OVERCURRENT);
+
+/* Power */
+static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, pem_show_input, NULL,
+ PEM_INPUT_POWER_LSB);
+static SENSOR_DEVICE_ATTR_2(power1_alarm, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_1, ALRM1_POWER_LIMIT);
+
+/* Fans */
+static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, pem_show_fan, NULL,
+ PEM_FAN_FAN1);
+static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, pem_show_fan, NULL,
+ PEM_FAN_FAN2);
+static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, pem_show_fan, NULL,
+ PEM_FAN_FAN3);
+static SENSOR_DEVICE_ATTR_2(fan1_alarm, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_2, ALRM2_FAN_FAULT);
+
+/* Temperatures */
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, pem_show_data, NULL,
+ PEM_DATA_TEMP);
+static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO, pem_show_data, NULL,
+ PEM_DATA_TEMP_MAX);
+static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, pem_show_data, NULL,
+ PEM_DATA_TEMP_CRIT);
+static SENSOR_DEVICE_ATTR_2(temp1_alarm, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_1, ALRM1_TEMP_WARNING);
+static SENSOR_DEVICE_ATTR_2(temp1_crit_alarm, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_1, ALRM1_TEMP_SHUTDOWN);
+static SENSOR_DEVICE_ATTR_2(temp1_fault, S_IRUGO, pem_show_bool, NULL,
+ PEM_DATA_ALARM_2, ALRM2_TEMP_FAULT);
+
+static struct attribute *pem_attributes[] = {
+ &sensor_dev_attr_in1_input.dev_attr.attr,
+ &sensor_dev_attr_in1_min_alarm.dev_attr.attr,
+ &sensor_dev_attr_in1_max_alarm.dev_attr.attr,
+ &sensor_dev_attr_in1_crit_alarm.dev_attr.attr,
+ &sensor_dev_attr_in2_alarm.dev_attr.attr,
+
+ &sensor_dev_attr_curr1_alarm.dev_attr.attr,
+
+ &sensor_dev_attr_power1_alarm.dev_attr.attr,
+
+ &sensor_dev_attr_fan1_alarm.dev_attr.attr,
+
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_temp1_max.dev_attr.attr,
+ &sensor_dev_attr_temp1_crit.dev_attr.attr,
+ &sensor_dev_attr_temp1_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
+ &sensor_dev_attr_temp1_fault.dev_attr.attr,
+
+ NULL,
+};
+
+static const struct attribute_group pem_group = {
+ .attrs = pem_attributes,
+};
+
+static struct attribute *pem_input_attributes[] = {
+ &sensor_dev_attr_in2_input.dev_attr.attr,
+ &sensor_dev_attr_curr1_input.dev_attr.attr,
+ &sensor_dev_attr_power1_input.dev_attr.attr,
+};
+
+static const struct attribute_group pem_input_group = {
+ .attrs = pem_input_attributes,
+};
+
+static struct attribute *pem_fan_attributes[] = {
+ &sensor_dev_attr_fan1_input.dev_attr.attr,
+ &sensor_dev_attr_fan2_input.dev_attr.attr,
+ &sensor_dev_attr_fan3_input.dev_attr.attr,
+};
+
+static const struct attribute_group pem_fan_group = {
+ .attrs = pem_fan_attributes,
+};
+
+static int pem_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct i2c_adapter *adapter = client->adapter;
+ struct pem_data *data;
+ int ret;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BLOCK_DATA
+ | I2C_FUNC_SMBUS_WRITE_BYTE))
+ return -ENODEV;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, data);
+ mutex_init(&data->update_lock);
+
+ /*
+ * We use the next two commands to determine if the device is really
+ * there.
+ */
+ ret = pem_read_block(client, PEM_READ_FIRMWARE_REV,
+ data->firmware_rev, sizeof(data->firmware_rev));
+ if (ret < 0)
+ goto out_kfree;
+
+ ret = i2c_smbus_write_byte(client, PEM_CLEAR_INFO_FLAGS);
+ if (ret < 0)
+ goto out_kfree;
+
+ dev_info(&client->dev, "Firmware revision %d.%d.%d\n",
+ data->firmware_rev[0], data->firmware_rev[1],
+ data->firmware_rev[2]);
+
+ /* Register sysfs hooks */
+ ret = sysfs_create_group(&client->dev.kobj, &pem_group);
+ if (ret)
+ goto out_kfree;
+
+ /*
+ * Check if input readings are supported.
+ * This is the case if we can read input data,
+ * and if the returned data is not all zeros.
+ * Note that input alarms are always supported.
+ */
+ ret = pem_read_block(client, PEM_READ_INPUT_STRING,
+ data->input_string,
+ sizeof(data->input_string) - 1);
+ if (!ret && (data->input_string[0] || data->input_string[1] ||
+ data->input_string[2]))
+ data->input_length = sizeof(data->input_string) - 1;
+ else if (ret < 0) {
+ /* Input string is one byte longer for some devices */
+ ret = pem_read_block(client, PEM_READ_INPUT_STRING,
+ data->input_string,
+ sizeof(data->input_string));
+ if (!ret && (data->input_string[0] || data->input_string[1] ||
+ data->input_string[2] || data->input_string[3]))
+ data->input_length = sizeof(data->input_string);
+ }
+ ret = 0;
+ if (data->input_length) {
+ ret = sysfs_create_group(&client->dev.kobj, &pem_input_group);
+ if (ret)
+ goto out_remove_groups;
+ }
+
+ /*
+ * Check if fan speed readings are supported.
+ * This is the case if we can read fan speed data,
+ * and if the returned data is not all zeros.
+ * Note that the fan alarm is always supported.
+ */
+ ret = pem_read_block(client, PEM_READ_FAN_SPEED,
+ data->fan_speed,
+ sizeof(data->fan_speed));
+ if (!ret && (data->fan_speed[0] || data->fan_speed[1] ||
+ data->fan_speed[2] || data->fan_speed[3])) {
+ data->fans_supported = true;
+ ret = sysfs_create_group(&client->dev.kobj, &pem_fan_group);
+ if (ret)
+ goto out_remove_groups;
+ }
+
+ data->hwmon_dev = hwmon_device_register(&client->dev);
+ if (IS_ERR(data->hwmon_dev)) {
+ ret = PTR_ERR(data->hwmon_dev);
+ goto out_remove_groups;
+ }
+
+ return 0;
+
+out_remove_groups:
+ sysfs_remove_group(&client->dev.kobj, &pem_input_group);
+ sysfs_remove_group(&client->dev.kobj, &pem_fan_group);
+ sysfs_remove_group(&client->dev.kobj, &pem_group);
+out_kfree:
+ kfree(data);
+ return ret;
+}
+
+static int pem_remove(struct i2c_client *client)
+{
+ struct pem_data *data = i2c_get_clientdata(client);
+
+ hwmon_device_unregister(data->hwmon_dev);
+
+ sysfs_remove_group(&client->dev.kobj, &pem_input_group);
+ sysfs_remove_group(&client->dev.kobj, &pem_fan_group);
+ sysfs_remove_group(&client->dev.kobj, &pem_group);
+
+ kfree(data);
+ return 0;
+}
+
+static const struct i2c_device_id pem_id[] = {
+ {"lineage_pem", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, pem_id);
+
+static struct i2c_driver pem_driver = {
+ .driver = {
+ .name = "lineage_pem",
+ },
+ .probe = pem_probe,
+ .remove = pem_remove,
+ .id_table = pem_id,
+};
+
+static int __init pem_init(void)
+{
+ return i2c_add_driver(&pem_driver);
+}
+
+static void __exit pem_exit(void)
+{
+ i2c_del_driver(&pem_driver);
+}
+
+MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>");
+MODULE_DESCRIPTION("Lineage CPL PEM hardware monitoring driver");
+MODULE_LICENSE("GPL");
+
+module_init(pem_init);
+module_exit(pem_exit);