diff options
| -rw-r--r-- | Documentation/i2c/chips/pcf8574 | 65 | ||||
| -rw-r--r-- | drivers/i2c/chips/Kconfig | 17 | ||||
| -rw-r--r-- | drivers/i2c/chips/Makefile | 1 | ||||
| -rw-r--r-- | drivers/i2c/chips/pcf8574.c | 215 |
4 files changed, 0 insertions, 298 deletions
diff --git a/Documentation/i2c/chips/pcf8574 b/Documentation/i2c/chips/pcf8574 deleted file mode 100644 index 235815c075f..00000000000 --- a/Documentation/i2c/chips/pcf8574 +++ /dev/null @@ -1,65 +0,0 @@ -Kernel driver pcf8574 -===================== - -Supported chips: - * Philips PCF8574 - Prefix: 'pcf8574' - Addresses scanned: none - Datasheet: Publicly available at the Philips Semiconductors website - http://www.semiconductors.philips.com/pip/PCF8574P.html - - * Philips PCF8574A - Prefix: 'pcf8574a' - Addresses scanned: none - Datasheet: Publicly available at the Philips Semiconductors website - http://www.semiconductors.philips.com/pip/PCF8574P.html - -Authors: - Frodo Looijaard <frodol@dds.nl>, - Philip Edelbrock <phil@netroedge.com>, - Dan Eaton <dan.eaton@rocketlogix.com>, - Aurelien Jarno <aurelien@aurel32.net>, - Jean Delvare <khali@linux-fr.org>, - - -Description ------------ -The PCF8574(A) is an 8-bit I/O expander for the I2C bus produced by Philips -Semiconductors. It is designed to provide a byte I2C interface to up to 16 -separate devices (8 x PCF8574 and 8 x PCF8574A). - -This device consists of a quasi-bidirectional port. Each of the eight I/Os -can be independently used as an input or output. To setup an I/O as an -input, you have to write a 1 to the corresponding output. - -For more informations see the datasheet. - - -Accessing PCF8574(A) via /sys interface -------------------------------------- - -The PCF8574(A) is plainly impossible to detect ! Stupid chip. -So, you have to pass the I2C bus and address of the installed PCF857A -and PCF8574A devices explicitly to the driver at load time via the -force=... parameter. - -On detection (i.e. insmod, modprobe et al.), directories are being -created for each detected PCF8574(A): - -/sys/bus/i2c/devices/<0>-<1>/ -where <0> is the bus the chip was detected on (e. g. i2c-0) -and <1> the chip address ([20..27] or [38..3f]): - -(example: /sys/bus/i2c/devices/1-0020/) - -Inside these directories, there are two files each: -read and write (and one file with chip name). - -The read file is read-only. Reading gives you the current I/O input -if the corresponding output is set as 1, otherwise the current output -value, that is to say 0. - -The write file is read/write. Writing a value outputs it on the I/O -port. Reading returns the last written value. As it is not possible -to read this value from the chip, you need to write at least once to -this file before you can read back from it. diff --git a/drivers/i2c/chips/Kconfig b/drivers/i2c/chips/Kconfig index 8cd1a7f3dcb..f9618f4d4e4 100644 --- a/drivers/i2c/chips/Kconfig +++ b/drivers/i2c/chips/Kconfig @@ -16,23 +16,6 @@ config DS1682 This driver can also be built as a module. If so, the module will be called ds1682. -config SENSORS_PCF8574 - tristate "Philips PCF8574 and PCF8574A (DEPRECATED)" - depends on EXPERIMENTAL && GPIO_PCF857X = "n" - default n - help - If you say yes here you get support for Philips PCF8574 and - PCF8574A chips. These chips are 8-bit I/O expanders for the I2C bus. - - This driver can also be built as a module. If so, the module - will be called pcf8574. - - This driver is deprecated and will be dropped soon. Use - drivers/gpio/pcf857x.c instead. - - These devices are hard to detect and rarely found on mainstream - hardware. If unsure, say N. - config SENSORS_TSL2550 tristate "Taos TSL2550 ambient light sensor" depends on EXPERIMENTAL diff --git a/drivers/i2c/chips/Makefile b/drivers/i2c/chips/Makefile index 8cd778dd64e..749cf360629 100644 --- a/drivers/i2c/chips/Makefile +++ b/drivers/i2c/chips/Makefile @@ -11,7 +11,6 @@ # obj-$(CONFIG_DS1682) += ds1682.o -obj-$(CONFIG_SENSORS_PCF8574) += pcf8574.o obj-$(CONFIG_SENSORS_TSL2550) += tsl2550.o ifeq ($(CONFIG_I2C_DEBUG_CHIP),y) diff --git a/drivers/i2c/chips/pcf8574.c b/drivers/i2c/chips/pcf8574.c deleted file mode 100644 index 6ec309894c8..00000000000 --- a/drivers/i2c/chips/pcf8574.c +++ /dev/null @@ -1,215 +0,0 @@ -/* - Copyright (c) 2000 Frodo Looijaard <frodol@dds.nl>, - Philip Edelbrock <phil@netroedge.com>, - Dan Eaton <dan.eaton@rocketlogix.com> - Ported to Linux 2.6 by Aurelien Jarno <aurel32@debian.org> with - the help of Jean Delvare <khali@linux-fr.org> - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. -*/ - -/* A few notes about the PCF8574: - -* The PCF8574 is an 8-bit I/O expander for the I2C bus produced by - Philips Semiconductors. It is designed to provide a byte I2C - interface to up to 8 separate devices. - -* The PCF8574 appears as a very simple SMBus device which can be - read from or written to with SMBUS byte read/write accesses. - - --Dan - -*/ - -#include <linux/module.h> -#include <linux/init.h> -#include <linux/slab.h> -#include <linux/i2c.h> - -/* Addresses to scan: none, device can't be detected */ -static const unsigned short normal_i2c[] = { I2C_CLIENT_END }; - -/* Insmod parameters */ -I2C_CLIENT_INSMOD_2(pcf8574, pcf8574a); - -/* Each client has this additional data */ -struct pcf8574_data { - int write; /* Remember last written value */ -}; - -static void pcf8574_init_client(struct i2c_client *client); - -/* following are the sysfs callback functions */ -static ssize_t show_read(struct device *dev, struct device_attribute *attr, char *buf) -{ - struct i2c_client *client = to_i2c_client(dev); - return sprintf(buf, "%u\n", i2c_smbus_read_byte(client)); -} - -static DEVICE_ATTR(read, S_IRUGO, show_read, NULL); - -static ssize_t show_write(struct device *dev, struct device_attribute *attr, char *buf) -{ - struct pcf8574_data *data = i2c_get_clientdata(to_i2c_client(dev)); - - if (data->write < 0) - return data->write; - - return sprintf(buf, "%d\n", data->write); -} - -static ssize_t set_write(struct device *dev, struct device_attribute *attr, const char *buf, - size_t count) -{ - struct i2c_client *client = to_i2c_client(dev); - struct pcf8574_data *data = i2c_get_clientdata(client); - unsigned long val = simple_strtoul(buf, NULL, 10); - - if (val > 0xff) - return -EINVAL; - - data->write = val; - i2c_smbus_write_byte(client, data->write); - return count; -} - -static DEVICE_ATTR(write, S_IWUSR | S_IRUGO, show_write, set_write); - -static struct attribute *pcf8574_attributes[] = { - &dev_attr_read.attr, - &dev_attr_write.attr, - NULL -}; - -static const struct attribute_group pcf8574_attr_group = { - .attrs = pcf8574_attributes, -}; - -/* - * Real code - */ - -/* Return 0 if detection is successful, -ENODEV otherwise */ -static int pcf8574_detect(struct i2c_client *client, int kind, - struct i2c_board_info *info) -{ - struct i2c_adapter *adapter = client->adapter; - const char *client_name; - - if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE)) - return -ENODEV; - - /* Now, we would do the remaining detection. But the PCF8574 is plainly - impossible to detect! Stupid chip. */ - - /* Determine the chip type */ - if (kind <= 0) { - if (client->addr >= 0x38 && client->addr <= 0x3f) - kind = pcf8574a; - else - kind = pcf8574; - } - - if (kind == pcf8574a) - client_name = "pcf8574a"; - else - client_name = "pcf8574"; - strlcpy(info->type, client_name, I2C_NAME_SIZE); - - return 0; -} - -static int pcf8574_probe(struct i2c_client *client, - const struct i2c_device_id *id) -{ - struct pcf8574_data *data; - int err; - - data = kzalloc(sizeof(struct pcf8574_data), GFP_KERNEL); - if (!data) { - err = -ENOMEM; - goto exit; - } - - i2c_set_clientdata(client, data); - - /* Initialize the PCF8574 chip */ - pcf8574_init_client(client); - - /* Register sysfs hooks */ - err = sysfs_create_group(&client->dev.kobj, &pcf8574_attr_group); - if (err) - goto exit_free; - return 0; - - exit_free: - kfree(data); - exit: - return err; -} - -static int pcf8574_remove(struct i2c_client *client) -{ - sysfs_remove_group(&client->dev.kobj, &pcf8574_attr_group); - kfree(i2c_get_clientdata(client)); - return 0; -} - -/* Called when we have found a new PCF8574. */ -static void pcf8574_init_client(struct i2c_client *client) -{ - struct pcf8574_data *data = i2c_get_clientdata(client); - data->write = -EAGAIN; -} - -static const struct i2c_device_id pcf8574_id[] = { - { "pcf8574", 0 }, - { "pcf8574a", 0 }, - { } -}; - -static struct i2c_driver pcf8574_driver = { - .driver = { - .name = "pcf8574", - }, - .probe = pcf8574_probe, - .remove = pcf8574_remove, - .id_table = pcf8574_id, - - .detect = pcf8574_detect, - .address_data = &addr_data, -}; - -static int __init pcf8574_init(void) -{ - return i2c_add_driver(&pcf8574_driver); -} - -static void __exit pcf8574_exit(void) -{ - i2c_del_driver(&pcf8574_driver); -} - - -MODULE_AUTHOR - ("Frodo Looijaard <frodol@dds.nl>, " - "Philip Edelbrock <phil@netroedge.com>, " - "Dan Eaton <dan.eaton@rocketlogix.com> " - "and Aurelien Jarno <aurelien@aurel32.net>"); -MODULE_DESCRIPTION("PCF8574 driver"); -MODULE_LICENSE("GPL"); - -module_init(pcf8574_init); -module_exit(pcf8574_exit); |