hwmon: (it87) Create voltage attributes only if voltage is enabled

On IT8782F and IT8783F, some voltage input pins may be disabled. Don't create
sysfs attribute files if that is the case.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 124 insertions, 38 deletions

diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c
index aebac1334ff6..bef8732f08b1 100644
--- a/drivers/hwmon/it87.c
+++ b/drivers/hwmon/it87.c
@@ -234,6 +234,7 @@ struct it87_sio_data {
         u8 beep_pin;
         u8 internal;    /* Internal sensors can be labeled */
         /* Features skipped based on config or DMI */
+        u16 skip_in;
         u8 skip_vid;
         u8 skip_fan;
         u8 skip_pwm;
@@ -1371,41 +1372,73 @@ static ssize_t show_name(struct device *dev, struct device_attribute
 }
 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
 
-static struct attribute *it87_attributes[] = {
+static struct attribute *it87_attributes_in[9][5] = {
+{
         &sensor_dev_attr_in0_input.dev_attr.attr,
-        &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_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_in0_min.dev_attr.attr,
-        &sensor_dev_attr_in1_min.dev_attr.attr,
-        &sensor_dev_attr_in2_min.dev_attr.attr,
-        &sensor_dev_attr_in3_min.dev_attr.attr,
-        &sensor_dev_attr_in4_min.dev_attr.attr,
-        &sensor_dev_attr_in5_min.dev_attr.attr,
-        &sensor_dev_attr_in6_min.dev_attr.attr,
-        &sensor_dev_attr_in7_min.dev_attr.attr,
         &sensor_dev_attr_in0_max.dev_attr.attr,
-        &sensor_dev_attr_in1_max.dev_attr.attr,
-        &sensor_dev_attr_in2_max.dev_attr.attr,
-        &sensor_dev_attr_in3_max.dev_attr.attr,
-        &sensor_dev_attr_in4_max.dev_attr.attr,
-        &sensor_dev_attr_in5_max.dev_attr.attr,
-        &sensor_dev_attr_in6_max.dev_attr.attr,
-        &sensor_dev_attr_in7_max.dev_attr.attr,
         &sensor_dev_attr_in0_alarm.dev_attr.attr,
+        NULL
+}, {
+        &sensor_dev_attr_in1_input.dev_attr.attr,
+        &sensor_dev_attr_in1_min.dev_attr.attr,
+        &sensor_dev_attr_in1_max.dev_attr.attr,
         &sensor_dev_attr_in1_alarm.dev_attr.attr,
+        NULL
+}, {
+        &sensor_dev_attr_in2_input.dev_attr.attr,
+        &sensor_dev_attr_in2_min.dev_attr.attr,
+        &sensor_dev_attr_in2_max.dev_attr.attr,
         &sensor_dev_attr_in2_alarm.dev_attr.attr,
+        NULL
+}, {
+        &sensor_dev_attr_in3_input.dev_attr.attr,
+        &sensor_dev_attr_in3_min.dev_attr.attr,
+        &sensor_dev_attr_in3_max.dev_attr.attr,
         &sensor_dev_attr_in3_alarm.dev_attr.attr,
+        NULL
+}, {
+        &sensor_dev_attr_in4_input.dev_attr.attr,
+        &sensor_dev_attr_in4_min.dev_attr.attr,
+        &sensor_dev_attr_in4_max.dev_attr.attr,
         &sensor_dev_attr_in4_alarm.dev_attr.attr,
+        NULL
+}, {
+        &sensor_dev_attr_in5_input.dev_attr.attr,
+        &sensor_dev_attr_in5_min.dev_attr.attr,
+        &sensor_dev_attr_in5_max.dev_attr.attr,
         &sensor_dev_attr_in5_alarm.dev_attr.attr,
+        NULL
+}, {
+        &sensor_dev_attr_in6_input.dev_attr.attr,
+        &sensor_dev_attr_in6_min.dev_attr.attr,
+        &sensor_dev_attr_in6_max.dev_attr.attr,
         &sensor_dev_attr_in6_alarm.dev_attr.attr,
+        NULL
+}, {
+        &sensor_dev_attr_in7_input.dev_attr.attr,
+        &sensor_dev_attr_in7_min.dev_attr.attr,
+        &sensor_dev_attr_in7_max.dev_attr.attr,
         &sensor_dev_attr_in7_alarm.dev_attr.attr,
+        NULL
+}, {
+        &sensor_dev_attr_in8_input.dev_attr.attr,
+        NULL
+} };
+
+static const struct attribute_group it87_group_in[9] = {
+        { .attrs = it87_attributes_in[0] },
+        { .attrs = it87_attributes_in[1] },
+        { .attrs = it87_attributes_in[2] },
+        { .attrs = it87_attributes_in[3] },
+        { .attrs = it87_attributes_in[4] },
+        { .attrs = it87_attributes_in[5] },
+        { .attrs = it87_attributes_in[6] },
+        { .attrs = it87_attributes_in[7] },
+        { .attrs = it87_attributes_in[8] },
+};
 
+static struct attribute *it87_attributes[] = {
         &sensor_dev_attr_temp1_input.dev_attr.attr,
         &sensor_dev_attr_temp2_input.dev_attr.attr,
         &sensor_dev_attr_temp3_input.dev_attr.attr,
@@ -1432,7 +1465,7 @@ static const struct attribute_group it87_group = {
         .attrs = it87_attributes,
 };
 
-static struct attribute *it87_attributes_beep[] = {
+static struct attribute *it87_attributes_in_beep[] = {
         &sensor_dev_attr_in0_beep.dev_attr.attr,
         &sensor_dev_attr_in1_beep.dev_attr.attr,
         &sensor_dev_attr_in2_beep.dev_attr.attr,
@@ -1441,7 +1474,10 @@ static struct attribute *it87_attributes_beep[] = {
         &sensor_dev_attr_in5_beep.dev_attr.attr,
         &sensor_dev_attr_in6_beep.dev_attr.attr,
         &sensor_dev_attr_in7_beep.dev_attr.attr,
+        NULL
+};
 
+static struct attribute *it87_attributes_beep[] = {
         &sensor_dev_attr_temp1_beep.dev_attr.attr,
         &sensor_dev_attr_temp2_beep.dev_attr.attr,
         &sensor_dev_attr_temp3_beep.dev_attr.attr,
@@ -1696,7 +1732,6 @@ static int __init it87_find(unsigned short *address,
                 sio_data->beep_pin = superio_inb(IT87_SIO_BEEP_PIN_REG) & 0x3f;
         } else if (sio_data->type == it8783) {
                 int reg25, reg27, reg2A, reg2C, regEF;
-                bool uart6;
 
                 sio_data->skip_vid = 1; /* No VID */
 
@@ -1708,10 +1743,8 @@ static int __init it87_find(unsigned short *address,
                 reg2C = superio_inb(IT87_SIO_PINX2_REG);
                 regEF = superio_inb(IT87_SIO_SPI_REG);
 
-                uart6 = reg2C & (1 << 2);
-
                 /* Check if fan3 is there or not */
-                if ((reg27 & (1 << 0)) || !uart6)
+                if ((reg27 & (1 << 0)) || !(reg2C & (1 << 2)))
                         sio_data->skip_fan |= (1 << 2);
                 if ((reg25 & (1 << 4))
                     || (!(reg2A & (1 << 1)) && (regEF & (1 << 0))))
@@ -1724,19 +1757,39 @@ static int __init it87_find(unsigned short *address,
                         sio_data->skip_pwm |= (1 << 1);
 
                 /* VIN5 */
-                if ((reg27 & (1 << 0)) || uart6)
-                        ; /* No VIN5 */
+                if ((reg27 & (1 << 0)) || (reg2C & (1 << 2)))
+                        sio_data->skip_in |= (1 << 5); /* No VIN5 */
 
                 /* VIN6 */
-                if ((reg27 & (1 << 1)) || uart6)
-                        ; /* No VIN6 */
+                if (reg27 & (1 << 1))
+                        sio_data->skip_in |= (1 << 6); /* No VIN6 */
 
                 /*
                  * VIN7
                  * Does not depend on bit 2 of Reg2C, contrary to datasheet.
                  */
-                if (reg27 & (1 << 2))
-                        ; /* No VIN7 (unless internal) */
+                if (reg27 & (1 << 2)) {
+                        /*
+                         * The data sheet is a bit unclear regarding the
+                         * internal voltage divider for VCCH5V. It says
+                         * "This bit enables and switches VIN7 (pin 91) to the
+                         * internal voltage divider for VCCH5V".
+                         * This is different to other chips, where the internal
+                         * voltage divider would connect VIN7 to an internal
+                         * voltage source. Maybe that is the case here as well.
+                         *
+                         * Since we don't know for sure, re-route it if that is
+                         * not the case, and ask the user to report if the
+                         * resulting voltage is sane.
+                         */
+                        if (!(reg2C & (1 << 1))) {
+                                reg2C |= (1 << 1);
+                                superio_outb(IT87_SIO_PINX2_REG, reg2C);
+                                pr_notice("Routing internal VCCH5V to in7.\n");
+                        }
+                        pr_notice("in7 routed to internal voltage divider, with external pin disabled.\n");
+                        pr_notice("Please report if it displays a reasonable voltage.\n");
+                }
 
                 if (reg2C & (1 << 0))
                         sio_data->internal |= (1 << 0);
@@ -1747,6 +1800,7 @@ static int __init it87_find(unsigned short *address,
 
         } else {
                 int reg;
+                bool uart6;
 
                 superio_select(GPIO);
 
@@ -1784,6 +1838,9 @@ static int __init it87_find(unsigned short *address,
                         sio_data->vid_value = superio_inb(IT87_SIO_VID_REG);
 
                 reg = superio_inb(IT87_SIO_PINX2_REG);
+
+                uart6 = sio_data->type == it8782 && (reg & (1 << 2));
+
                 /*
                  * The IT8720F has no VIN7 pin, so VCCH should always be
                  * routed internally to VIN7 with an internal divider.
@@ -1795,11 +1852,10 @@ static int __init it87_find(unsigned short *address,
                  * setting. So we force the internal routing in this case.
                  *
                  * On IT8782F, VIN7 is multiplexed with one of the UART6 pins.
-                 * If UART6 is enabled, re-route VIN7 to the internal divider.
+                 * If UART6 is enabled, re-route VIN7 to the internal divider
+                 * if that is not already the case.
                  */
-                if ((sio_data->type == it8720 ||
-                    (sio_data->type == it8782 && (reg & (1 << 2))))
-                    && !(reg & (1 << 1))) {
+                if ((sio_data->type == it8720 || uart6) && !(reg & (1 << 1))) {
                         reg |= (1 << 1);
                         superio_outb(IT87_SIO_PINX2_REG, reg);
                         pr_notice("Routing internal VCCH to in7\n");
@@ -1810,6 +1866,14 @@ static int __init it87_find(unsigned short *address,
                     sio_data->type == it8728)
                         sio_data->internal |= (1 << 1);
 
+                /*
+                 * On IT8782F, UART6 pins overlap with VIN5, VIN6, and VIN7.
+                 * While VIN7 can be routed to the internal voltage divider,
+                 * VIN5 and VIN6 are not available if UART6 is enabled.
+                 */
+                if (uart6)
+                        sio_data->skip_in |= (1 << 5) | (1 << 6);
+
                 sio_data->beep_pin = superio_inb(IT87_SIO_BEEP_PIN_REG) & 0x3f;
         }
         if (sio_data->beep_pin)
@@ -1847,6 +1911,14 @@ static void it87_remove_files(struct device *dev)
         int i;
 
         sysfs_remove_group(&dev->kobj, &it87_group);
+        for (i = 0; i < 9; i++) {
+                if (sio_data->skip_in & (1 << i))
+                        continue;
+                sysfs_remove_group(&dev->kobj, &it87_group_in[i]);
+                if (it87_attributes_in_beep[i])
+                        sysfs_remove_file(&dev->kobj,
+                                          it87_attributes_in_beep[i]);
+        }
         if (sio_data->beep_pin)
                 sysfs_remove_group(&dev->kobj, &it87_group_beep);
         for (i = 0; i < 5; i++) {
@@ -1949,6 +2021,20 @@ static int __devinit it87_probe(struct platform_device *pdev)
         if (err)
                 goto ERROR2;
 
+        for (i = 0; i < 9; i++) {
+                if (sio_data->skip_in & (1 << i))
+                        continue;
+                err = sysfs_create_group(&dev->kobj, &it87_group_in[i]);
+                if (err)
+                        goto ERROR4;
+                if (sio_data->beep_pin && it87_attributes_in_beep[i]) {
+                        err = sysfs_create_file(&dev->kobj,
+                                                it87_attributes_in_beep[i]);
+                        if (err)
+                                goto ERROR4;
+                }
+        }
+
         if (sio_data->beep_pin) {
                 err = sysfs_create_group(&dev->kobj, &it87_group_beep);
                 if (err)