[PATCH] I2C: Invert as99127f beep bits in kernel space

The following patch changes the way we invert beep bits for the AS99127F
sensor chip. This chip behaves differently from the other chips in that
a disabled bit is 1, not 0. So far we didn't handle that specificity in
the w83781d driver, so it was left to user-space applications to handle
it. For the sake of uniformity, it's obviously better if it's done in
the driver instead (although the meaning of each bit is still
chip-dependant).

I already did a similar change to the 2.4 driver and the sensors
program. I don't think that many user-space application will be
affected, since most of them don't handle the beep mask as far as I can
tell.

This also close Debian bug #209299:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=209299

Successfully tested on my AS99127F rev.1 chip. Aurelien Jarno also
checked that there were no regression on non-Asus chips.

drivers/i2c/chips/w83781d.c

@@ -183,8 +183,10 @@ FAN_TO_REG(long rpm, int div)
 #define ALARMS_FROM_REG(val)		(val)
 #define PWM_FROM_REG(val)		(val)
 #define PWM_TO_REG(val)			(SENSORS_LIMIT((val),0,255))
-#define BEEP_MASK_FROM_REG(val)		(val)
-#define BEEP_MASK_TO_REG(val)		((val) & 0xffffff)
+#define BEEP_MASK_FROM_REG(val,type)	((type) == as99127f ? \
+					 (val) ^ 0x7fff : (val))
+#define BEEP_MASK_TO_REG(val,type)	((type) == as99127f ? \
+					 (~(val)) & 0x7fff : (val) & 0xffffff)
 
 #define BEEP_ENABLE_TO_REG(val)		((val) ? 1 : 0)
 #define BEEP_ENABLE_FROM_REG(val)	((val) ? 1 : 0)
@@ -539,14 +541,18 @@ static
 DEVICE_ATTR(alarms, S_IRUGO, show_alarms_reg, NULL)
 #define device_create_file_alarms(client) \
 device_create_file(&client->dev, &dev_attr_alarms);
-#define show_beep_reg(REG, reg) \
-static ssize_t show_beep_##reg (struct device *dev, char *buf) \
-{ \
-	struct w83781d_data *data = w83781d_update_device(dev); \
-	return sprintf(buf,"%ld\n", (long)BEEP_##REG##_FROM_REG(data->beep_##reg)); \
+static ssize_t show_beep_mask (struct device *dev, char *buf)
+{
+	struct w83781d_data *data = w83781d_update_device(dev);
+	return sprintf(buf, "%ld\n",
+		       (long)BEEP_MASK_FROM_REG(data->beep_mask, data->type));
+}
+static ssize_t show_beep_enable (struct device *dev, char *buf)
+{
+	struct w83781d_data *data = w83781d_update_device(dev);
+	return sprintf(buf, "%ld\n",
+		       (long)BEEP_ENABLE_FROM_REG(data->beep_enable));
 }
-show_beep_reg(ENABLE, enable);
-show_beep_reg(MASK, mask);
 
 #define BEEP_ENABLE			0	/* Store beep_enable */
 #define BEEP_MASK			1	/* Store beep_mask */
@@ -562,7 +568,7 @@ store_beep_reg(struct device *dev, const char *buf, size_t count,
 	val = simple_strtoul(buf, NULL, 10);
 
 	if (update_mask == BEEP_MASK) {	/* We are storing beep_mask */
-		data->beep_mask = BEEP_MASK_TO_REG(val);
+		data->beep_mask = BEEP_MASK_TO_REG(val, data->type);
 		w83781d_write_value(client, W83781D_REG_BEEP_INTS1,
 				    data->beep_mask & 0xff);