hwmon: (pc87427) Add support for manual fan speed control
Add initial support for PWM outputs of the PC87427 Super-I/O chip.
Only mode change and manual fan speed control are supported. Automatic
mode configuration isn't supported, and won't be until at least one
board is known, which makes uses of the PWM outputs.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
diff --git a/drivers/hwmon/pc87427.c b/drivers/hwmon/pc87427.c
index 0ac55ba..8698227 100644
--- a/drivers/hwmon/pc87427.c
+++ b/drivers/hwmon/pc87427.c
@@ -15,10 +15,10 @@
* Supports the following chips:
*
* Chip #vin #fan #pwm #temp devid
- * PC87427 - 8 - - 0xF2
+ * PC87427 - 8 4 - 0xF2
*
* This driver assumes that no more than one chip is present.
- * Only fan inputs are supported so far, although the chip can do much more.
+ * Only fans are supported so far, although the chip can do much more.
*/
#include <linux/module.h>
@@ -57,10 +57,16 @@
u16 fan[8]; /* register values */
u16 fan_min[8]; /* register values */
u8 fan_status[8]; /* register values */
+
+ u8 pwm_enabled; /* bit vector */
+ u8 pwm_auto_ok; /* bit vector */
+ u8 pwm_enable[4]; /* register values */
+ u8 pwm[4]; /* register values */
};
struct pc87427_sio_data {
u8 has_fanin;
+ u8 has_fanout;
};
/*
@@ -72,7 +78,9 @@
#define SIOREG_CF2 0x22 /* Configuration 2 */
#define SIOREG_CF3 0x23 /* Configuration 3 */
#define SIOREG_CF4 0x24 /* Configuration 4 */
+#define SIOREG_CF5 0x25 /* Configuration 5 */
#define SIOREG_CFB 0x2B /* Configuration B */
+#define SIOREG_CFC 0x2C /* Configuration C */
#define SIOREG_CFD 0x2D /* Configuration D */
#define SIOREG_ACT 0x30 /* Device activation */
#define SIOREG_MAP 0x50 /* I/O or memory mapping */
@@ -188,6 +196,61 @@
}
/*
+ * PWM registers and conversions
+ */
+
+#define PC87427_REG_PWM_ENABLE 0x10
+#define PC87427_REG_PWM_DUTY 0x12
+
+#define PWM_ENABLE_MODE_MASK (7 << 4)
+#define PWM_ENABLE_CTLEN (1 << 0)
+
+#define PWM_MODE_MANUAL (0 << 4)
+#define PWM_MODE_AUTO (1 << 4)
+#define PWM_MODE_OFF (2 << 4)
+#define PWM_MODE_ON (7 << 4)
+
+/* Dedicated function to read all registers related to a given PWM output.
+ This saves us quite a few locks and bank selections.
+ Must be called with data->lock held.
+ nr is from 0 to 3 */
+static void pc87427_readall_pwm(struct pc87427_data *data, u8 nr)
+{
+ int iobase = data->address[LD_FAN];
+
+ outb(BANK_FC(nr), iobase + PC87427_REG_BANK);
+ data->pwm_enable[nr] = inb(iobase + PC87427_REG_PWM_ENABLE);
+ data->pwm[nr] = inb(iobase + PC87427_REG_PWM_DUTY);
+}
+
+static inline int pwm_enable_from_reg(u8 reg)
+{
+ switch (reg & PWM_ENABLE_MODE_MASK) {
+ case PWM_MODE_ON:
+ return 0;
+ case PWM_MODE_MANUAL:
+ case PWM_MODE_OFF:
+ return 1;
+ case PWM_MODE_AUTO:
+ return 2;
+ default:
+ return -EPROTO;
+ }
+}
+
+static inline u8 pwm_enable_to_reg(unsigned long val, u8 pwmval)
+{
+ switch (val) {
+ default:
+ return PWM_MODE_ON;
+ case 1:
+ return pwmval ? PWM_MODE_MANUAL : PWM_MODE_OFF;
+ case 2:
+ return PWM_MODE_AUTO;
+ }
+}
+
+/*
* Data interface
*/
@@ -207,6 +270,14 @@
continue;
pc87427_readall_fan(data, i);
}
+
+ /* PWM outputs */
+ for (i = 0; i < 4; i++) {
+ if (!(data->pwm_enabled & (1 << i)))
+ continue;
+ pc87427_readall_pwm(data, i);
+ }
+
data->last_updated = jiffies;
done:
@@ -384,6 +455,145 @@
{ .attrs = pc87427_attributes_fan[7] },
};
+/* Must be called with data->lock held and pc87427_readall_pwm() freshly
+ called */
+static void update_pwm_enable(struct pc87427_data *data, int nr, u8 mode)
+{
+ int iobase = data->address[LD_FAN];
+ data->pwm_enable[nr] &= ~PWM_ENABLE_MODE_MASK;
+ data->pwm_enable[nr] |= mode;
+ outb(data->pwm_enable[nr], iobase + PC87427_REG_PWM_ENABLE);
+}
+
+static ssize_t show_pwm_enable(struct device *dev, struct device_attribute
+ *devattr, char *buf)
+{
+ struct pc87427_data *data = pc87427_update_device(dev);
+ int nr = to_sensor_dev_attr(devattr)->index;
+ int pwm_enable;
+
+ pwm_enable = pwm_enable_from_reg(data->pwm_enable[nr]);
+ if (pwm_enable < 0)
+ return pwm_enable;
+ return sprintf(buf, "%d\n", pwm_enable);
+}
+
+static ssize_t set_pwm_enable(struct device *dev, struct device_attribute
+ *devattr, const char *buf, size_t count)
+{
+ struct pc87427_data *data = dev_get_drvdata(dev);
+ int nr = to_sensor_dev_attr(devattr)->index;
+ unsigned long val;
+
+ if (strict_strtoul(buf, 10, &val) < 0 || val > 2)
+ return -EINVAL;
+ /* Can't go to automatic mode if it isn't configured */
+ if (val == 2 && !(data->pwm_auto_ok & (1 << nr)))
+ return -EINVAL;
+
+ mutex_lock(&data->lock);
+ pc87427_readall_pwm(data, nr);
+ update_pwm_enable(data, nr, pwm_enable_to_reg(val, data->pwm[nr]));
+ mutex_unlock(&data->lock);
+
+ return count;
+}
+
+static ssize_t show_pwm(struct device *dev, struct device_attribute
+ *devattr, char *buf)
+{
+ struct pc87427_data *data = pc87427_update_device(dev);
+ int nr = to_sensor_dev_attr(devattr)->index;
+
+ return sprintf(buf, "%d\n", (int)data->pwm[nr]);
+}
+
+static ssize_t set_pwm(struct device *dev, struct device_attribute
+ *devattr, const char *buf, size_t count)
+{
+ struct pc87427_data *data = dev_get_drvdata(dev);
+ int nr = to_sensor_dev_attr(devattr)->index;
+ unsigned long val;
+ int iobase = data->address[LD_FAN];
+ u8 mode;
+
+ if (strict_strtoul(buf, 10, &val) < 0 || val > 0xff)
+ return -EINVAL;
+
+ mutex_lock(&data->lock);
+ pc87427_readall_pwm(data, nr);
+ mode = data->pwm_enable[nr] & PWM_ENABLE_MODE_MASK;
+ if (mode != PWM_MODE_MANUAL && mode != PWM_MODE_OFF) {
+ dev_notice(dev, "Can't set PWM%d duty cycle while not in "
+ "manual mode\n", nr + 1);
+ mutex_unlock(&data->lock);
+ return -EPERM;
+ }
+
+ /* We may have to change the mode */
+ if (mode == PWM_MODE_MANUAL && val == 0) {
+ /* Transition from Manual to Off */
+ update_pwm_enable(data, nr, PWM_MODE_OFF);
+ mode = PWM_MODE_OFF;
+ dev_dbg(dev, "Switching PWM%d from %s to %s\n", nr + 1,
+ "manual", "off");
+ } else if (mode == PWM_MODE_OFF && val != 0) {
+ /* Transition from Off to Manual */
+ update_pwm_enable(data, nr, PWM_MODE_MANUAL);
+ mode = PWM_MODE_MANUAL;
+ dev_dbg(dev, "Switching PWM%d from %s to %s\n", nr + 1,
+ "off", "manual");
+ }
+
+ data->pwm[nr] = val;
+ if (mode == PWM_MODE_MANUAL)
+ outb(val, iobase + PC87427_REG_PWM_DUTY);
+ mutex_unlock(&data->lock);
+
+ return count;
+}
+
+static SENSOR_DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO,
+ show_pwm_enable, set_pwm_enable, 0);
+static SENSOR_DEVICE_ATTR(pwm2_enable, S_IWUSR | S_IRUGO,
+ show_pwm_enable, set_pwm_enable, 1);
+static SENSOR_DEVICE_ATTR(pwm3_enable, S_IWUSR | S_IRUGO,
+ show_pwm_enable, set_pwm_enable, 2);
+static SENSOR_DEVICE_ATTR(pwm4_enable, S_IWUSR | S_IRUGO,
+ show_pwm_enable, set_pwm_enable, 3);
+
+static SENSOR_DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 0);
+static SENSOR_DEVICE_ATTR(pwm2, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 1);
+static SENSOR_DEVICE_ATTR(pwm3, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 2);
+static SENSOR_DEVICE_ATTR(pwm4, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 3);
+
+static struct attribute *pc87427_attributes_pwm[4][3] = {
+ {
+ &sensor_dev_attr_pwm1_enable.dev_attr.attr,
+ &sensor_dev_attr_pwm1.dev_attr.attr,
+ NULL
+ }, {
+ &sensor_dev_attr_pwm2_enable.dev_attr.attr,
+ &sensor_dev_attr_pwm2.dev_attr.attr,
+ NULL
+ }, {
+ &sensor_dev_attr_pwm3_enable.dev_attr.attr,
+ &sensor_dev_attr_pwm3.dev_attr.attr,
+ NULL
+ }, {
+ &sensor_dev_attr_pwm4_enable.dev_attr.attr,
+ &sensor_dev_attr_pwm4.dev_attr.attr,
+ NULL
+ }
+};
+
+static const struct attribute_group pc87427_group_pwm[4] = {
+ { .attrs = pc87427_attributes_pwm[0] },
+ { .attrs = pc87427_attributes_pwm[1] },
+ { .attrs = pc87427_attributes_pwm[2] },
+ { .attrs = pc87427_attributes_pwm[3] },
+};
+
static ssize_t show_name(struct device *dev, struct device_attribute
*devattr, char *buf)
{
@@ -431,6 +641,25 @@
}
data->fan_enabled = sio_data->has_fanin;
}
+
+ /* Check which PWM outputs are enabled */
+ for (i = 0; i < 4; i++) {
+ if (!(sio_data->has_fanout & (1 << i))) /* Not wired */
+ continue;
+ reg = pc87427_read8_bank(data, LD_FAN, BANK_FC(i),
+ PC87427_REG_PWM_ENABLE);
+ if (reg & PWM_ENABLE_CTLEN)
+ data->pwm_enabled |= (1 << i);
+
+ /* We don't expose an interface to reconfigure the automatic
+ fan control mode, so only allow to return to this mode if
+ it was originally set. */
+ if ((reg & PWM_ENABLE_MODE_MASK) == PWM_MODE_AUTO) {
+ dev_dbg(dev, "PWM%d is in automatic control mode\n",
+ i + 1);
+ data->pwm_auto_ok |= (1 << i);
+ }
+ }
}
static int __devinit pc87427_probe(struct platform_device *pdev)
@@ -474,6 +703,14 @@
if (err)
goto exit_remove_files;
}
+ for (i = 0; i < 4; i++) {
+ if (!(data->pwm_enabled & (1 << i)))
+ continue;
+ err = sysfs_create_group(&pdev->dev.kobj,
+ &pc87427_group_pwm[i]);
+ if (err)
+ goto exit_remove_files;
+ }
data->hwmon_dev = hwmon_device_register(&pdev->dev);
if (IS_ERR(data->hwmon_dev)) {
@@ -490,6 +727,11 @@
continue;
sysfs_remove_group(&pdev->dev.kobj, &pc87427_group_fan[i]);
}
+ for (i = 0; i < 4; i++) {
+ if (!(data->pwm_enabled & (1 << i)))
+ continue;
+ sysfs_remove_group(&pdev->dev.kobj, &pc87427_group_pwm[i]);
+ }
exit_release_region:
release_region(res->start, resource_size(res));
exit_kfree:
@@ -512,6 +754,11 @@
continue;
sysfs_remove_group(&pdev->dev.kobj, &pc87427_group_fan[i]);
}
+ for (i = 0; i < 4; i++) {
+ if (!(data->pwm_enabled & (1 << i)))
+ continue;
+ sysfs_remove_group(&pdev->dev.kobj, &pc87427_group_pwm[i]);
+ }
platform_set_drvdata(pdev, NULL);
kfree(data);
@@ -648,6 +895,26 @@
if ((cfg & (1 << 3)) && !(cfg_b & (1 << 5)))
sio_data->has_fanin |= (1 << 6); /* FANIN6 */
+ /* Check which fan outputs are wired */
+ sio_data->has_fanout = (1 << 0); /* FANOUT0 */
+ if (cfg_b & (1 << 0))
+ sio_data->has_fanout |= (1 << 3); /* FANOUT3 */
+
+ cfg = superio_inb(sioaddr, SIOREG_CFC);
+ if (!(cfg & (1 << 4))) {
+ if (cfg_b & (1 << 1))
+ sio_data->has_fanout |= (1 << 1); /* FANOUT1 */
+ if (cfg_b & (1 << 2))
+ sio_data->has_fanout |= (1 << 2); /* FANOUT2 */
+ }
+
+ /* FANOUT1 and FANOUT2 can each be routed to 2 different pins */
+ cfg = superio_inb(sioaddr, SIOREG_CF5);
+ if (cfg & (1 << 6))
+ sio_data->has_fanout |= (1 << 1); /* FANOUT1 */
+ if (cfg & (1 << 5))
+ sio_data->has_fanout |= (1 << 2); /* FANOUT2 */
+
exit:
superio_exit(sioaddr);
return err;