hwmon: (it87) Export labels for internal sensors

Some voltage sensors can be wired internally to the IT87xxF chip's own
power supply channels. In that case, we can inform user-space that the
wiring is known by exporting proper labels for these sensors.

Signed-off-by: Jean Delvare <khali@linux-fr.org>

diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c
index 25763d2..f770129 100644 (file)
--- a/drivers/hwmon/it87.c
+++ b/drivers/hwmon/it87.c
@@ -259,6 +259,7 @@ struct it87_sio_data {
        u8 revision;
        u8 vid_value;
        u8 beep_pin;
+       u8 internal;    /* Internal sensors can be labeled */
        /* Features skipped based on config or DMI */
        u8 skip_vid;
        u8 skip_fan;
@@ -1194,6 +1195,22 @@ static ssize_t show_vid_reg(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid_reg, NULL);
 
+static ssize_t show_label(struct device *dev, struct device_attribute *attr,
+               char *buf)
+{
+       static const char *labels[] = {
+               "+5V",
+               "5VSB",
+               "Vbat",
+       };
+       int nr = to_sensor_dev_attr(attr)->index;
+
+       return sprintf(buf, "%s\n", labels[nr]);
+}
+static SENSOR_DEVICE_ATTR(in3_label, S_IRUGO, show_label, NULL, 0);
+static SENSOR_DEVICE_ATTR(in7_label, S_IRUGO, show_label, NULL, 1);
+static SENSOR_DEVICE_ATTR(in8_label, S_IRUGO, show_label, NULL, 2);
+
 static ssize_t show_name(struct device *dev, struct device_attribute
                         *devattr, char *buf)
 {
@@ -1434,6 +1451,17 @@ static const struct attribute_group it87_group_vid = {
        .attrs = it87_attributes_vid,
 };
 
+static struct attribute *it87_attributes_label[] = {
+       &sensor_dev_attr_in3_label.dev_attr.attr,
+       &sensor_dev_attr_in7_label.dev_attr.attr,
+       &sensor_dev_attr_in8_label.dev_attr.attr,
+       NULL
+};
+
+static const struct attribute_group it87_group_label = {
+       .attrs = it87_attributes_vid,
+};
+
 /* SuperIO detection - will change isa_address if a chip is found */
 static int __init it87_find(unsigned short *address,
        struct it87_sio_data *sio_data)
@@ -1487,6 +1515,9 @@ static int __init it87_find(unsigned short *address,
        pr_info("it87: Found IT%04xF chip at 0x%x, revision %d\n",
                chip_type, *address, sio_data->revision);
 
+       /* in8 (Vbat) is always internal */
+       sio_data->internal = (1 << 2);
+
        /* Read GPIO config and VID value from LDN 7 (GPIO) */
        if (sio_data->type == it87) {
                /* The IT8705F doesn't have VID pins at all */
@@ -1540,9 +1571,9 @@ static int __init it87_find(unsigned short *address,
                        pr_notice("it87: Routing internal VCCH to in7\n");
                }
                if (reg & (1 << 0))
-                       pr_info("it87: in3 is VCC (+5V)\n");
+                       sio_data->internal |= (1 << 0);
                if (reg & (1 << 1))
-                       pr_info("it87: in7 is VCCH (+5V Stand-By)\n");
+                       sio_data->internal |= (1 << 1);
 
                sio_data->beep_pin = superio_inb(IT87_SIO_BEEP_PIN_REG) & 0x3f;
        }
@@ -1600,6 +1631,7 @@ static void it87_remove_files(struct device *dev)
        }
        if (!sio_data->skip_vid)
                sysfs_remove_group(&dev->kobj, &it87_group_vid);
+       sysfs_remove_group(&dev->kobj, &it87_group_label);
 }
 
 static int __devinit it87_probe(struct platform_device *pdev)
@@ -1725,6 +1757,16 @@ static int __devinit it87_probe(struct platform_device *pdev)
                        goto ERROR4;
        }
 
+       /* Export labels for internal sensors */
+       for (i = 0; i < 3; i++) {
+               if (!(sio_data->internal & (1 << i)))
+                       continue;
+               err = sysfs_create_file(&dev->kobj,
+                                       it87_attributes_label[i]);
+               if (err)
+                       goto ERROR4;
+       }
+
        data->hwmon_dev = hwmon_device_register(dev);
        if (IS_ERR(data->hwmon_dev)) {
                err = PTR_ERR(data->hwmon_dev);