]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - drivers/hwmon/it87.c
hwmon: (it87) Prevent power-off on Shuttle SN68PT
[linux-2.6-omap-h63xx.git] / drivers / hwmon / it87.c
index ca0a723cbce526efae9b365dd3da6df1bc738bb6..d793cc0119908abd5494ed9f531a27f3dbbb478b 100644 (file)
@@ -46,6 +46,8 @@
 #include <linux/err.h>
 #include <linux/mutex.h>
 #include <linux/sysfs.h>
+#include <linux/string.h>
+#include <linux/dmi.h>
 #include <asm/io.h>
 
 #define DRVNAME "it87"
@@ -151,9 +153,9 @@ static int fix_pwm_polarity;
 /* The IT8718F has the VID value in a different register, in Super-I/O
    configuration space. */
 #define IT87_REG_VID           0x0a
-/* Warning: register 0x0b is used for something completely different in
-   new chips/revisions. I suspect only 16-bit tachometer mode will work
-   for these. */
+/* The IT8705F and IT8712F earlier than revision 0x08 use register 0x0b
+   for fan divisors. Later IT8712F revisions must use 16-bit tachometer
+   mode. */
 #define IT87_REG_FAN_DIV       0x0b
 #define IT87_REG_FAN_16BIT     0x0c
 
@@ -234,7 +236,10 @@ static const unsigned int pwm_freq[8] = {
 struct it87_sio_data {
        enum chips type;
        /* Values read from Super-I/O config space */
+       u8 revision;
        u8 vid_value;
+       /* Values set based on DMI strings */
+       u8 skip_pwm;
 };
 
 /* For each registered chip, we need to keep some data in memory.
@@ -242,6 +247,7 @@ struct it87_sio_data {
 struct it87_data {
        struct device *hwmon_dev;
        enum chips type;
+       u8 revision;
 
        unsigned short addr;
        const char *name;
@@ -268,6 +274,16 @@ struct it87_data {
        u8 manual_pwm_ctl[3];   /* manual PWM value set by user */
 };
 
+static inline int has_16bit_fans(const struct it87_data *data)
+{
+       /* IT8705F Datasheet 0.4.1, 3h == Version G.
+          IT8712F Datasheet 0.9.1, section 8.3.5 indicates 8h == Version J.
+          These are the first revisions with 16bit tachometer support. */
+       return (data->type == it87 && data->revision >= 0x03)
+           || (data->type == it8712 && data->revision >= 0x08)
+           || data->type == it8716
+           || data->type == it8718;
+}
 
 static int it87_probe(struct platform_device *pdev);
 static int __devexit it87_remove(struct platform_device *pdev);
@@ -933,6 +949,9 @@ static struct attribute *it87_attributes_opt[] = {
        &sensor_dev_attr_pwm1.dev_attr.attr,
        &sensor_dev_attr_pwm2.dev_attr.attr,
        &sensor_dev_attr_pwm3.dev_attr.attr,
+       &dev_attr_pwm1_freq.attr,
+       &dev_attr_pwm2_freq.attr,
+       &dev_attr_pwm3_freq.attr,
 
        &dev_attr_vrm.attr,
        &dev_attr_cpu0_vid.attr,
@@ -949,6 +968,7 @@ static int __init it87_find(unsigned short *address,
 {
        int err = -ENODEV;
        u16 chip_type;
+       const char *board_vendor, *board_name;
 
        superio_enter();
        chip_type = force_id ? force_id : superio_inw(DEVID);
@@ -988,8 +1008,9 @@ static int __init it87_find(unsigned short *address,
        }
 
        err = 0;
+       sio_data->revision = superio_inb(DEVREV) & 0x0f;
        pr_info("it87: Found IT%04xF chip at 0x%x, revision %d\n",
-               chip_type, *address, superio_inb(DEVREV) & 0x0f);
+               chip_type, *address, sio_data->revision);
 
        /* Read GPIO config and VID value from LDN 7 (GPIO) */
        if (chip_type != IT8705F_DEVID) {
@@ -1006,6 +1027,24 @@ static int __init it87_find(unsigned short *address,
                        pr_info("it87: in7 is VCCH (+5V Stand-By)\n");
        }
 
+       /* Disable specific features based on DMI strings */
+       board_vendor = dmi_get_system_info(DMI_BOARD_VENDOR);
+       board_name = dmi_get_system_info(DMI_BOARD_NAME);
+       if (board_vendor && board_name) {
+               if (strcmp(board_vendor, "nVIDIA") == 0
+                && strcmp(board_name, "FN68PT") == 0) {
+                       /* On the Shuttle SN68PT, FAN_CTL2 is apparently not
+                          connected to a fan, but to something else. One user
+                          has reported instant system power-off when changing
+                          the PWM2 duty cycle, so we disable it.
+                          I use the board name string as the trigger in case
+                          the same board is ever used in other systems. */
+                       pr_info("it87: Disabling pwm2 due to "
+                               "hardware constraints\n");
+                       sio_data->skip_pwm = (1 << 1);
+               }
+       }
+
 exit:
        superio_exit();
        return err;
@@ -1042,6 +1081,7 @@ static int __devinit it87_probe(struct platform_device *pdev)
 
        data->addr = res->start;
        data->type = sio_data->type;
+       data->revision = sio_data->revision;
        data->name = names[sio_data->type];
 
        /* Now, we do the remaining detection. */
@@ -1066,7 +1106,7 @@ static int __devinit it87_probe(struct platform_device *pdev)
                goto ERROR2;
 
        /* Do not create fan files for disabled fans */
-       if (data->type == it8716 || data->type == it8718) {
+       if (has_16bit_fans(data)) {
                /* 16-bit tachometers */
                if (data->has_fan & (1 << 0)) {
                        if ((err = device_create_file(dev,
@@ -1151,25 +1191,33 @@ static int __devinit it87_probe(struct platform_device *pdev)
        }
 
        if (enable_pwm_interface) {
-               if ((err = device_create_file(dev,
-                    &sensor_dev_attr_pwm1_enable.dev_attr))
-                || (err = device_create_file(dev,
-                    &sensor_dev_attr_pwm2_enable.dev_attr))
-                || (err = device_create_file(dev,
-                    &sensor_dev_attr_pwm3_enable.dev_attr))
-                || (err = device_create_file(dev,
-                    &sensor_dev_attr_pwm1.dev_attr))
-                || (err = device_create_file(dev,
-                    &sensor_dev_attr_pwm2.dev_attr))
-                || (err = device_create_file(dev,
-                    &sensor_dev_attr_pwm3.dev_attr))
-                || (err = device_create_file(dev,
-                    &dev_attr_pwm1_freq))
-                || (err = device_create_file(dev,
-                    &dev_attr_pwm2_freq))
-                || (err = device_create_file(dev,
-                    &dev_attr_pwm3_freq)))
-                       goto ERROR4;
+               if (!(sio_data->skip_pwm & (1 << 0))) {
+                       if ((err = device_create_file(dev,
+                            &sensor_dev_attr_pwm1_enable.dev_attr))
+                        || (err = device_create_file(dev,
+                            &sensor_dev_attr_pwm1.dev_attr))
+                        || (err = device_create_file(dev,
+                            &dev_attr_pwm1_freq)))
+                               goto ERROR4;
+               }
+               if (!(sio_data->skip_pwm & (1 << 1))) {
+                       if ((err = device_create_file(dev,
+                            &sensor_dev_attr_pwm2_enable.dev_attr))
+                        || (err = device_create_file(dev,
+                            &sensor_dev_attr_pwm2.dev_attr))
+                        || (err = device_create_file(dev,
+                            &dev_attr_pwm2_freq)))
+                               goto ERROR4;
+               }
+               if (!(sio_data->skip_pwm & (1 << 2))) {
+                       if ((err = device_create_file(dev,
+                            &sensor_dev_attr_pwm3_enable.dev_attr))
+                        || (err = device_create_file(dev,
+                            &sensor_dev_attr_pwm3.dev_attr))
+                        || (err = device_create_file(dev,
+                            &dev_attr_pwm3_freq)))
+                               goto ERROR4;
+               }
        }
 
        if (data->type == it8712 || data->type == it8716
@@ -1347,7 +1395,7 @@ static void __devinit it87_init_device(struct platform_device *pdev)
        data->has_fan = (data->fan_main_ctrl >> 4) & 0x07;
 
        /* Set tachometers to 16-bit mode if needed */
-       if (data->type == it8716 || data->type == it8718) {
+       if (has_16bit_fans(data)) {
                tmp = it87_read_value(data, IT87_REG_FAN_16BIT);
                if (~tmp & 0x07 & data->has_fan) {
                        dev_dbg(&pdev->dev,
@@ -1355,10 +1403,13 @@ static void __devinit it87_init_device(struct platform_device *pdev)
                        it87_write_value(data, IT87_REG_FAN_16BIT,
                                         tmp | 0x07);
                }
-               if (tmp & (1 << 4))
-                       data->has_fan |= (1 << 3);      /* fan4 enabled */
-               if (tmp & (1 << 5))
-                       data->has_fan |= (1 << 4);      /* fan5 enabled */
+               /* IT8705F only supports three fans. */
+               if (data->type != it87) {
+                       if (tmp & (1 << 4))
+                               data->has_fan |= (1 << 3); /* fan4 enabled */
+                       if (tmp & (1 << 5))
+                               data->has_fan |= (1 << 4); /* fan5 enabled */
+               }
        }
 
        /* Set current fan mode registers and the default settings for the
@@ -1423,7 +1474,7 @@ static struct it87_data *it87_update_device(struct device *dev)
                        data->fan[i] = it87_read_value(data,
                                       IT87_REG_FAN[i]);
                        /* Add high byte if in 16-bit mode */
-                       if (data->type == it8716 || data->type == it8718) {
+                       if (has_16bit_fans(data)) {
                                data->fan[i] |= it87_read_value(data,
                                                IT87_REG_FANX[i]) << 8;
                                data->fan_min[i] |= it87_read_value(data,
@@ -1440,8 +1491,7 @@ static struct it87_data *it87_update_device(struct device *dev)
                }
 
                /* Newer chips don't have clock dividers */
-               if ((data->has_fan & 0x07) && data->type != it8716
-                && data->type != it8718) {
+               if ((data->has_fan & 0x07) && !has_16bit_fans(data)) {
                        i = it87_read_value(data, IT87_REG_FAN_DIV);
                        data->fan_div[0] = i & 0x07;
                        data->fan_div[1] = (i >> 3) & 0x07;
@@ -1457,7 +1507,8 @@ static struct it87_data *it87_update_device(struct device *dev)
                data->fan_ctl = it87_read_value(data, IT87_REG_FAN_CTL);
 
                data->sensor = it87_read_value(data, IT87_REG_TEMP_ENABLE);
-               /* The 8705 does not have VID capability */
+               /* The 8705 does not have VID capability.
+                  The 8718 does not use IT87_REG_VID for the same purpose. */
                if (data->type == it8712 || data->type == it8716) {
                        data->vid = it87_read_value(data, IT87_REG_VID);
                        /* The older IT8712F revisions had only 5 VID pins,
@@ -1526,6 +1577,7 @@ static int __init sm_it87_init(void)
        unsigned short isa_address=0;
        struct it87_sio_data sio_data;
 
+       memset(&sio_data, 0, sizeof(struct it87_sio_data));
        err = it87_find(&isa_address, &sio_data);
        if (err)
                return err;