i2c/chips: Remove deprecated pcf8575 driver
The pcf8575 driver in drivers/i2c/chips which just exports its register to sysfs is superseded by drivers/gpio/pcf857x.c which properly uses the gpiolib. As this driver has been deprecated for more than a year, finally remove it. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Cc: Bart Van Assche <bart.vanassche@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
This commit is contained in:
Wolfram Sang
Jean Delvare
parent
4ba2ccb83e
commit
8f67eeb0b4
|
|
@ -1,69 +0,0 @@
|
|||
About the PCF8575 chip and the pcf8575 kernel driver
|
||||
====================================================
|
||||
|
||||
The PCF8575 chip is produced by the following manufacturers:
|
||||
|
||||
* Philips NXP
|
||||
http://www.nxp.com/#/pip/cb=[type=product,path=50807/41735/41850,final=PCF8575_3]|pip=[pip=PCF8575_3][0]
|
||||
|
||||
* Texas Instruments
|
||||
http://focus.ti.com/docs/prod/folders/print/pcf8575.html
|
||||
|
||||
|
||||
Some vendors sell small PCB's with the PCF8575 mounted on it. You can connect
|
||||
such a board to a Linux host via e.g. an USB to I2C interface. Examples of
|
||||
PCB boards with a PCF8575:
|
||||
|
||||
* SFE Breakout Board for PCF8575 I2C Expander by RobotShop
|
||||
http://www.robotshop.ca/home/products/robot-parts/electronics/adapters-converters/sfe-pcf8575-i2c-expander-board.html
|
||||
|
||||
* Breakout Board for PCF8575 I2C Expander by Spark Fun Electronics
|
||||
http://www.sparkfun.com/commerce/product_info.php?products_id=8130
|
||||
|
||||
|
||||
Description
|
||||
-----------
|
||||
The PCF8575 chip is a 16-bit I/O expander for the I2C bus. Up to eight of
|
||||
these chips can be connected to the same I2C bus. You can find this
|
||||
chip on some custom designed hardware, but you won't find it on PC
|
||||
motherboards.
|
||||
|
||||
The PCF8575 chip consists of a 16-bit quasi-bidirectional port and an I2C-bus
|
||||
interface. Each of the sixteen I/O's can be independently used as an input or
|
||||
an output. To set up an I/O pin as an input, you have to write a 1 to the
|
||||
corresponding output.
|
||||
|
||||
For more information please see the datasheet.
|
||||
|
||||
|
||||
Detection
|
||||
---------
|
||||
|
||||
There is no method known to detect whether a chip on a given I2C address is
|
||||
a PCF8575 or whether it is any other I2C device, so you have to pass the I2C
|
||||
bus and address of the installed PCF8575 devices explicitly to the driver at
|
||||
load time via the force=... parameter.
|
||||
|
||||
/sys interface
|
||||
--------------
|
||||
|
||||
For each address on which a PCF8575 chip was found or forced the following
|
||||
files will be created under /sys:
|
||||
* /sys/bus/i2c/devices/<bus>-<address>/read
|
||||
* /sys/bus/i2c/devices/<bus>-<address>/write
|
||||
where bus is the I2C bus number (0, 1, ...) and address is the four-digit
|
||||
hexadecimal representation of the 7-bit I2C address of the PCF8575
|
||||
(0020 .. 0027).
|
||||
|
||||
The read file is read-only. Reading it will trigger an I2C read and will hence
|
||||
report the current input state for the pins configured as inputs, and the
|
||||
current output value for the pins configured as outputs.
|
||||
|
||||
The write file is read-write. Writing a value to it will configure all pins
|
||||
as output for which the corresponding bit is zero. Reading the write file will
|
||||
return the value last written, or -EAGAIN if no value has yet been written to
|
||||
the write file.
|
||||
|
||||
On module initialization the configuration of the chip is not changed -- the
|
||||
chip is left in the state it was already configured in through either power-up
|
||||
or through previous I2C write actions.
|
||||
|
|
@ -33,24 +33,6 @@ config SENSORS_PCF8574
|
|||
These devices are hard to detect and rarely found on mainstream
|
||||
hardware. If unsure, say N.
|
||||
|
||||
config PCF8575
|
||||
tristate "Philips PCF8575 (DEPRECATED)"
|
||||
default n
|
||||
depends on GPIO_PCF857X = "n"
|
||||
help
|
||||
If you say yes here you get support for Philips PCF8575 chip.
|
||||
This chip is a 16-bit I/O expander for the I2C bus. Several other
|
||||
chip manufacturers sell equivalent chips, e.g. Texas Instruments.
|
||||
|
||||
This driver can also be built as a module. If so, the module
|
||||
will be called pcf8575.
|
||||
|
||||
This driver is deprecated and will be dropped soon. Use
|
||||
drivers/gpio/pcf857x.c instead.
|
||||
|
||||
This device is hard to detect and is rarely found on mainstream
|
||||
hardware. If unsure, say N.
|
||||
|
||||
config SENSORS_PCA9539
|
||||
tristate "Philips PCA9539 16-bit I/O port (DEPRECATED)"
|
||||
depends on EXPERIMENTAL && GPIO_PCA953X = "n"
|
||||
|
|
|
|||
|
|
@ -13,7 +13,6 @@
|
|||
obj-$(CONFIG_DS1682) += ds1682.o
|
||||
obj-$(CONFIG_SENSORS_PCA9539) += pca9539.o
|
||||
obj-$(CONFIG_SENSORS_PCF8574) += pcf8574.o
|
||||
obj-$(CONFIG_PCF8575) += pcf8575.o
|
||||
obj-$(CONFIG_SENSORS_TSL2550) += tsl2550.o
|
||||
|
||||
ifeq ($(CONFIG_I2C_DEBUG_CHIP),y)
|
||||
|
|
|
|||
|
|
@ -1,198 +0,0 @@
|
|||
/*
|
||||
pcf8575.c
|
||||
|
||||
About the PCF8575 chip: the PCF8575 is a 16-bit I/O expander for the I2C bus
|
||||
produced by a.o. Philips Semiconductors.
|
||||
|
||||
Copyright (C) 2006 Michael Hennerich, Analog Devices Inc.
|
||||
<hennerich@blackfin.uclinux.org>
|
||||
Based on pcf8574.c.
|
||||
|
||||
Copyright (c) 2007 Bart Van Assche <bart.vanassche@gmail.com>.
|
||||
Ported this driver from ucLinux to the mainstream Linux kernel.
|
||||
|
||||
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.
|
||||
*/
|
||||
|
||||
#include <linux/module.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/i2c.h>
|
||||
#include <linux/slab.h> /* kzalloc() */
|
||||
#include <linux/sysfs.h> /* sysfs_create_group() */
|
||||
|
||||
/* Addresses to scan: none, device can't be detected */
|
||||
static const unsigned short normal_i2c[] = { I2C_CLIENT_END };
|
||||
|
||||
/* Insmod parameters */
|
||||
I2C_CLIENT_INSMOD;
|
||||
|
||||
|
||||
/* Each client has this additional data */
|
||||
struct pcf8575_data {
|
||||
int write; /* last written value, or error code */
|
||||
};
|
||||
|
||||
/* 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);
|
||||
u16 val;
|
||||
u8 iopin_state[2];
|
||||
|
||||
i2c_master_recv(client, iopin_state, 2);
|
||||
|
||||
val = iopin_state[0];
|
||||
val |= iopin_state[1] << 8;
|
||||
|
||||
return sprintf(buf, "%u\n", val);
|
||||
}
|
||||
|
||||
static DEVICE_ATTR(read, S_IRUGO, show_read, NULL);
|
||||
|
||||
static ssize_t show_write(struct device *dev, struct device_attribute *attr,
|
||||
char *buf)
|
||||
{
|
||||
struct pcf8575_data *data = dev_get_drvdata(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 pcf8575_data *data = i2c_get_clientdata(client);
|
||||
unsigned long val = simple_strtoul(buf, NULL, 10);
|
||||
u8 iopin_state[2];
|
||||
|
||||
if (val > 0xffff)
|
||||
return -EINVAL;
|
||||
|
||||
data->write = val;
|
||||
|
||||
iopin_state[0] = val & 0xFF;
|
||||
iopin_state[1] = val >> 8;
|
||||
|
||||
i2c_master_send(client, iopin_state, 2);
|
||||
|
||||
return count;
|
||||
}
|
||||
|
||||
static DEVICE_ATTR(write, S_IWUSR | S_IRUGO, show_write, set_write);
|
||||
|
||||
static struct attribute *pcf8575_attributes[] = {
|
||||
&dev_attr_read.attr,
|
||||
&dev_attr_write.attr,
|
||||
NULL
|
||||
};
|
||||
|
||||
static const struct attribute_group pcf8575_attr_group = {
|
||||
.attrs = pcf8575_attributes,
|
||||
};
|
||||
|
||||
/*
|
||||
* Real code
|
||||
*/
|
||||
|
||||
/* Return 0 if detection is successful, -ENODEV otherwise */
|
||||
static int pcf8575_detect(struct i2c_client *client, int kind,
|
||||
struct i2c_board_info *info)
|
||||
{
|
||||
struct i2c_adapter *adapter = client->adapter;
|
||||
|
||||
if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
|
||||
return -ENODEV;
|
||||
|
||||
/* This is the place to detect whether the chip at the specified
|
||||
address really is a PCF8575 chip. However, there is no method known
|
||||
to detect whether an I2C chip is a PCF8575 or any other I2C chip. */
|
||||
|
||||
strlcpy(info->type, "pcf8575", I2C_NAME_SIZE);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int pcf8575_probe(struct i2c_client *client,
|
||||
const struct i2c_device_id *id)
|
||||
{
|
||||
struct pcf8575_data *data;
|
||||
int err;
|
||||
|
||||
data = kzalloc(sizeof(struct pcf8575_data), GFP_KERNEL);
|
||||
if (!data) {
|
||||
err = -ENOMEM;
|
||||
goto exit;
|
||||
}
|
||||
|
||||
i2c_set_clientdata(client, data);
|
||||
data->write = -EAGAIN;
|
||||
|
||||
/* Register sysfs hooks */
|
||||
err = sysfs_create_group(&client->dev.kobj, &pcf8575_attr_group);
|
||||
if (err)
|
||||
goto exit_free;
|
||||
|
||||
return 0;
|
||||
|
||||
exit_free:
|
||||
kfree(data);
|
||||
exit:
|
||||
return err;
|
||||
}
|
||||
|
||||
static int pcf8575_remove(struct i2c_client *client)
|
||||
{
|
||||
sysfs_remove_group(&client->dev.kobj, &pcf8575_attr_group);
|
||||
kfree(i2c_get_clientdata(client));
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct i2c_device_id pcf8575_id[] = {
|
||||
{ "pcf8575", 0 },
|
||||
{ }
|
||||
};
|
||||
|
||||
static struct i2c_driver pcf8575_driver = {
|
||||
.driver = {
|
||||
.owner = THIS_MODULE,
|
||||
.name = "pcf8575",
|
||||
},
|
||||
.probe = pcf8575_probe,
|
||||
.remove = pcf8575_remove,
|
||||
.id_table = pcf8575_id,
|
||||
|
||||
.detect = pcf8575_detect,
|
||||
.address_data = &addr_data,
|
||||
};
|
||||
|
||||
static int __init pcf8575_init(void)
|
||||
{
|
||||
return i2c_add_driver(&pcf8575_driver);
|
||||
}
|
||||
|
||||
static void __exit pcf8575_exit(void)
|
||||
{
|
||||
i2c_del_driver(&pcf8575_driver);
|
||||
}
|
||||
|
||||
MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>, "
|
||||
"Bart Van Assche <bart.vanassche@gmail.com>");
|
||||
MODULE_DESCRIPTION("pcf8575 driver");
|
||||
MODULE_LICENSE("GPL");
|
||||
|
||||
module_init(pcf8575_init);
|
||||
module_exit(pcf8575_exit);
|
||||
Reference in New Issue