Move the pcf8591 driver to hwmon

Directory drivers/i2c/chips is going away, so drivers there must find
new homes. For the pcf8591 driver, the best choice seems to be the
hwmon subsystem. While the Philips PCF8591 device isn't a typical
hardware monitoring chip, its DAC interface is compatible with the
hwmon one, so it fits somewhat.

If a better subsystem is ever created for ADC/DAC chips, the driver
could be moved there.

Signed-off-by: Jean Delvare <[e-mail]>
Cc: Aurelien Jarno <[e-mail]>

drivers/hwmon/Kconfig

···
 	  This driver can also be built as a module.  If so, the module
 	  will be called pc87427.
 
+config SENSORS_PCF8591
+	tristate "Philips PCF8591 ADC/DAC"
+	depends on I2C
+	default n
+	help
+	  If you say yes here you get support for Philips PCF8591 4-channel
+	  ADC, 1-channel DAC chips.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called pcf8591.
+
+	  These devices are hard to detect and rarely found on mainstream
+	  hardware.  If unsure, say N.
+
 config SENSORS_SIS5595
 	tristate "Silicon Integrated Systems Corp. SiS5595"
 	depends on PCI

drivers/hwmon/Makefile

···
 obj-$(CONFIG_SENSORS_MAX6650)	+= max6650.o
 obj-$(CONFIG_SENSORS_PC87360)	+= pc87360.o
 obj-$(CONFIG_SENSORS_PC87427)	+= pc87427.o
+obj-$(CONFIG_SENSORS_PCF8591)	+= pcf8591.o
 obj-$(CONFIG_SENSORS_SIS5595)	+= sis5595.o
 obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o
 obj-$(CONFIG_SENSORS_SMSC47M1)	+= smsc47m1.o

drivers/i2c/chips/Kconfig

···
 	  This driver is deprecated and will be dropped soon. Use
 	  drivers/gpio/pca953x.c instead.
 
-config SENSORS_PCF8591
-	tristate "Philips PCF8591"
-	depends on EXPERIMENTAL
-	default n
-	help
-	  If you say yes here you get support for Philips PCF8591 chips.
-
-	  This driver can also be built as a module.  If so, the module
-	  will be called pcf8591.
-
-	  These devices are hard to detect and rarely found on mainstream
-	  hardware.  If unsure, say N.
-
 config SENSORS_MAX6875
 	tristate "Maxim MAX6875 Power supply supervisor"
 	depends on EXPERIMENTAL

drivers/i2c/chips/Makefile

···
 obj-$(CONFIG_SENSORS_PCA9539)	+= pca9539.o
 obj-$(CONFIG_SENSORS_PCF8574)	+= pcf8574.o
 obj-$(CONFIG_PCF8575)		+= pcf8575.o
-obj-$(CONFIG_SENSORS_PCF8591)	+= pcf8591.o
 obj-$(CONFIG_SENSORS_TSL2550)	+= tsl2550.o
 
 ifeq ($(CONFIG_I2C_DEBUG_CHIP),y)

drivers/i2c/chips/pcf8591.c drivers/hwmon/pcf8591.c

···
 /*
     Copyright (C) 2001-2004 Aurelien Jarno <[e-mail]>
-    Ported to Linux 2.6 by Aurelien Jarno <[e-mail]> with 
+    Ported to Linux 2.6 by Aurelien Jarno <[e-mail]> with
     the help of Jean Delvare <[e-mail]>
 
     This program is free software; you can redistribute it and/or modify
···
 	" 3 = two differential inputs\n");
 
 /* The PCF8591 control byte
-      7    6    5    4    3    2    1    0  
+      7    6    5    4    3    2    1    0
    |  0 |AOEF|   AIP   |  0 |AINC|  AICH   | */
 
 /* Analog Output Enable Flag (analog output active if 1) */
 #define PCF8591_CONTROL_AOEF		0x40
-					
-/* Analog Input Programming 
+
+/* Analog Input Programming
    0x00 = four single ended inputs
    0x10 = three differential inputs
    0x20 = single ended and differential mixed
···
 #define PCF8591_CONTROL_AINC		0x04
 
 /* Channel selection
-   0x00 = channel 0 
+   0x00 = channel 0
    0x01 = channel 1
    0x02 = channel 2
    0x03 = channel 3 */
···
 	return -EINVAL;
 }
 
-static DEVICE_ATTR(out0_output, S_IWUSR | S_IRUGO, 
+static DEVICE_ATTR(out0_output, S_IWUSR | S_IRUGO,
 		   show_out0_ouput, set_out0_output);
 
 static ssize_t show_out0_enable(struct device *dev, struct device_attribute *attr, char *buf)
···
 	return count;
 }
 
-static DEVICE_ATTR(out0_enable, S_IWUSR | S_IRUGO, 
+static DEVICE_ATTR(out0_enable, S_IWUSR | S_IRUGO,
 		   show_out0_enable, set_out0_enable);
 
 static struct attribute *pcf8591_attributes[] = {
···
 		err = -ENOMEM;
 		goto exit;
 	}
-	
+
 	i2c_set_clientdata(client, data);
 	mutex_init(&data->update_lock);
 
···
 	data->aout = PCF8591_INIT_AOUT;
 
 	i2c_smbus_write_byte_data(client, data->control, data->aout);
-	
-	/* The first byte transmitted contains the conversion code of the 
+
+	/* The first byte transmitted contains the conversion code of the
 	   previous read cycle. FLUSH IT! */
 	i2c_smbus_read_byte(client);
 }
···
 		data->control = (data->control & ~PCF8591_CONTROL_AICH_MASK)
 			      | channel;
 		i2c_smbus_write_byte(client, data->control);
-	
-		/* The first byte transmitted contains the conversion code of 
+
+		/* The first byte transmitted contains the conversion code of
 		   the previous read cycle. FLUSH IT! */
 		i2c_smbus_read_byte(client);
 	}