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Diffstat (limited to 'drivers/i2c/chips/pcf8574.c')
-rw-r--r--drivers/i2c/chips/pcf8574.c234
1 files changed, 0 insertions, 234 deletions
diff --git a/drivers/i2c/chips/pcf8574.c b/drivers/i2c/chips/pcf8574.c
deleted file mode 100644
index e5b31329b56..00000000000
--- a/drivers/i2c/chips/pcf8574.c
+++ /dev/null
@@ -1,234 +0,0 @@
-/*
- pcf8574.c - Part of lm_sensors, Linux kernel modules for hardware
- monitoring
- 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 */
-static const unsigned short normal_i2c[] = {
- 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
- 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
- I2C_CLIENT_END
-};
-
-/* Insmod parameters */
-I2C_CLIENT_INSMOD_2(pcf8574, pcf8574a);
-
-/* Each client has this additional data */
-struct pcf8574_data {
- struct i2c_client client;
-
- int write; /* Remember last written value */
-};
-
-static int pcf8574_attach_adapter(struct i2c_adapter *adapter);
-static int pcf8574_detect(struct i2c_adapter *adapter, int address, int kind);
-static int pcf8574_detach_client(struct i2c_client *client);
-static void pcf8574_init_client(struct i2c_client *client);
-
-/* This is the driver that will be inserted */
-static struct i2c_driver pcf8574_driver = {
- .driver = {
- .name = "pcf8574",
- },
- .attach_adapter = pcf8574_attach_adapter,
- .detach_client = pcf8574_detach_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
- */
-
-static int pcf8574_attach_adapter(struct i2c_adapter *adapter)
-{
- return i2c_probe(adapter, &addr_data, pcf8574_detect);
-}
-
-/* This function is called by i2c_probe */
-static int pcf8574_detect(struct i2c_adapter *adapter, int address, int kind)
-{
- struct i2c_client *new_client;
- struct pcf8574_data *data;
- int err = 0;
- const char *client_name = "";
-
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
- goto exit;
-
- /* OK. For now, we presume we have a valid client. We now create the
- client structure, even though we cannot fill it completely yet. */
- if (!(data = kzalloc(sizeof(struct pcf8574_data), GFP_KERNEL))) {
- err = -ENOMEM;
- goto exit;
- }
-
- new_client = &data->client;
- i2c_set_clientdata(new_client, data);
- new_client->addr = address;
- new_client->adapter = adapter;
- new_client->driver = &pcf8574_driver;
- new_client->flags = 0;
-
- /* 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 (address >= 0x38 && address <= 0x3f)
- kind = pcf8574a;
- else
- kind = pcf8574;
- }
-
- if (kind == pcf8574a)
- client_name = "pcf8574a";
- else
- client_name = "pcf8574";
-
- /* Fill in the remaining client fields and put it into the global list */
- strlcpy(new_client->name, client_name, I2C_NAME_SIZE);
-
- /* Tell the I2C layer a new client has arrived */
- if ((err = i2c_attach_client(new_client)))
- goto exit_free;
-
- /* Initialize the PCF8574 chip */
- pcf8574_init_client(new_client);
-
- /* Register sysfs hooks */
- err = sysfs_create_group(&new_client->dev.kobj, &pcf8574_attr_group);
- if (err)
- goto exit_detach;
- return 0;
-
- exit_detach:
- i2c_detach_client(new_client);
- exit_free:
- kfree(data);
- exit:
- return err;
-}
-
-static int pcf8574_detach_client(struct i2c_client *client)
-{
- int err;
-
- sysfs_remove_group(&client->dev.kobj, &pcf8574_attr_group);
-
- if ((err = i2c_detach_client(client)))
- return err;
-
- 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 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);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 14:55:02 +0000