Fixed documentation thanks to David Hubbard
============
Added support for the MAX7311 i2c io port expanders. This driver is
based on the pcf8574 driver which supports the same kind of chip.
Signed off by Walter Goossens <waltergoossens at home.nl>
diff -uarN -x '*.o' -x '*.ko' linux-2.6.17/drivers/i2c/chips/Kconfig
linux-2.6.17-mpe04/drivers/i2c/chips/Kconfig
--- linux-2.6.17/drivers/i2c/chips/Kconfig 2006-06-18
01:49:35.000000000 +0000
+++ linux-2.6.17-mpe04/drivers/i2c/chips/Kconfig 2006-10-18
11:00:05.000000000 +0000
@@ -117,4 +117,23 @@
This driver can also be built as a module. If so, the module
will be called max6875.
+config SENSORS_MAX7311
+ tristate "Maxim MAX7311 16 port io expander"
+ depends on I2C
+ help
+ If you say yes here you will get support for the max7311 port
+ expander chip. This chip has 16 ioports each configurable for
+ input or output.
+
+ This driver can also be built as a module. If so, the module
+ will be called max7311.
+config SENSORS_MAX7311_NUMCLIENTS
+ int "Maximum number of chips"
+ default "4"
+ depends on SENSORS_MAX7311
+config SENSORS_MAX7311_ADDRESSES
+ string "Addresses to scan"
+ default "0x20 0x24"
+ depends on SENSORS_MAX7311
+
endmenu
diff -uarN -x '*.o' -x '*.ko' linux-2.6.17/drivers/i2c/chips/Makefile
linux-2.6.17-mpe04/drivers/i2c/chips/Makefile
--- linux-2.6.17/drivers/i2c/chips/Makefile 2006-06-18
01:49:35.000000000 +0000
+++ linux-2.6.17-mpe04/drivers/i2c/chips/Makefile 2006-10-18
10:00:29.000000000 +0000
@@ -6,6 +6,7 @@
obj-$(CONFIG_SENSORS_DS1374) += ds1374.o
obj-$(CONFIG_SENSORS_EEPROM) += eeprom.o
obj-$(CONFIG_SENSORS_MAX6875) += max6875.o
+obj-$(CONFIG_SENSORS_MAX7311) += max7311.o
obj-$(CONFIG_SENSORS_M41T00) += m41t00.o
obj-$(CONFIG_SENSORS_PCA9539) += pca9539.o
obj-$(CONFIG_SENSORS_PCF8574) += pcf8574.o
diff -uarN -x '*.o' -x '*.ko' linux-2.6.17/drivers/i2c/chips/max7311.c
linux-2.6.17-mpe04/drivers/i2c/chips/max7311.c
--- linux-2.6.17/drivers/i2c/chips/max7311.c 1970-01-01
00:00:00.000000000 +0000
+++ linux-2.6.17-mpe04/drivers/i2c/chips/max7311.c 2006-10-18
11:27:59.000000000 +0000
@@ -0,0 +1,352 @@
+/*
+ max7311.c
+ Copyright (c) 2006 Walter Goossens <walter.goossens at axon.tv>
+
+ Based on:
+
+ pcf8574.c - Part of lm_sensors, Linux kernel modules for hardware
+ monitoring
+ Copyright (c) 2000 Frodo Looijaard <frodol at dds.nl>,
+ Philip Edelbrock <phil at netroedge.com>,
+ Dan Eaton <dan.eaton at rocketlogix.com>
+ Ported to Linux 2.6 by Aurelien Jarno <aurel32 at debian.org> with
+ the help of Jean Delvare <khali at 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.
+*/
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/list.h>
+
+/* Addresses to scan */
+static unsigned short normal_i2c[CONFIG_SENSORS_MAX7311_NUMCLIENTS];
+
+/* Insmod parameters */
+I2C_CLIENT_INSMOD;
+
+/* Initial values */
+#define MAX7311_INIT 0xFFFF /* All ports in input */
+/* Chip registers */
+#define REG_INPUT 0x00
+#define REG_OUTPUT 0x02
+#define REG_POLARITY 0x04
+#define REG_CONFIG 0x06
+#define REG_TIMEOUT 0x08
+
+/* Keep a list of all registered clients */
+static LIST_HEAD(max7311_clients);
+
+/* Each client has this additional data */
+struct max7311_data {
+ struct i2c_client client;
+
+ uint16_t output;
+ uint16_t config;
+ uint16_t polarity;
+ struct list_head list;
+};
+
+
+static int max7311_attach_adapter(struct i2c_adapter *adapter);
+static int max7311_detect(struct i2c_adapter *adapter, int address, int
kind);
+static int max7311_detach_client(struct i2c_client *client);
+static void max7311_init_client(struct i2c_client *client);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver max7311_driver = {
+ .driver = {
+ .name = "max7311",
+ },
+ .id = I2C_DRIVERID_MAX7311,
+ .attach_adapter = max7311_attach_adapter,
+ .detach_client = max7311_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_word_data(client,REG_INPUT));
+}
+
+static DEVICE_ATTR(read, S_IRUGO, show_read, NULL);
+
+static ssize_t show_write(struct device *dev, struct device_attribute
*attr, char *buf)
+{
+ struct max7311_data *data = i2c_get_clientdata(to_i2c_client(dev));
+ return sprintf(buf, "%u\n", data->output);
+}
+
+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 max7311_data *data = i2c_get_clientdata(client);
+ unsigned long val = simple_strtoul(buf, NULL, 10);
+
+ if (val > 0xFFFF)
+ {
+ return -EINVAL;
+ }
+ data->output = val;
+ i2c_smbus_write_word_data(client, REG_OUTPUT,data->output);
+ return count;
+}
+
+static DEVICE_ATTR(write, S_IWUSR | S_IRUGO, show_write, set_write);
+
+static ssize_t show_config(struct device *dev, struct device_attribute
*attr, char *buf)
+{
+ struct max7311_data *data = i2c_get_clientdata(to_i2c_client(dev));
+ return sprintf(buf, "%u\n", data->config);
+}
+
+static ssize_t set_config(struct device *dev, struct device_attribute
*attr, const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max7311_data *data = i2c_get_clientdata(client);
+ unsigned long val = simple_strtoul(buf, NULL, 10);
+
+ if (val > 0xFFFF)
+ {
+ return -EINVAL;
+ }
+ data->config = val;
+ i2c_smbus_write_word_data(client, REG_CONFIG,data->config);
+ return count;
+}
+
+static DEVICE_ATTR(config, S_IWUSR | S_IRUGO, show_config, set_config);
+
+static ssize_t show_polarity(struct device *dev, struct
device_attribute *attr, char *buf)
+{
+ struct max7311_data *data = i2c_get_clientdata(to_i2c_client(dev));
+ return sprintf(buf, "%u\n", data->polarity);
+}
+
+static ssize_t set_polarity(struct device *dev, struct device_attribute
*attr, const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct max7311_data *data = i2c_get_clientdata(client);
+ unsigned long val = simple_strtoul(buf, NULL, 10);
+
+ if (val > 0xFFFF)
+ {
+ return -EINVAL;
+ }
+ data->polarity = val;
+ i2c_smbus_write_word_data(client, REG_CONFIG,data->polarity);
+ return count;
+}
+
+static DEVICE_ATTR(polarity, S_IWUSR | S_IRUGO, show_polarity,
set_polarity);
+
+/*
+ * Real code
+ */
+
+static int max7311_attach_adapter(struct i2c_adapter *adapter)
+{
+ return i2c_probe(adapter, &addr_data, max7311_detect);
+}
+
+/* This function is called by i2c_probe */
+static int max7311_detect(struct i2c_adapter *adapter, int address, int
kind)
+{
+ struct i2c_client *new_client;
+ struct max7311_data *data;
+ int err = 0;
+ /* Can out adapter suply everything we need ? */
+ if (!i2c_check_functionality(adapter,
I2C_FUNC_SMBUS_BYTE|I2C_FUNC_SMBUS_BYTE_DATA))
+ {
+ return -1;
+ }
+
+ /* 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 max7311_data), GFP_KERNEL))) {
+ err = -ENOMEM;
+ return err;
+ }
+
+ new_client = &data->client;
+ i2c_set_clientdata(new_client, data);
+ new_client->addr = address;
+ new_client->adapter = adapter;
+ new_client->driver = &max7311_driver;
+ new_client->flags = 0;
+
+ /* Fill in the remaining client fields and put it into the global list */
+ strlcpy(new_client->name, "max7311", I2C_NAME_SIZE);
+
+ /* Tell the I2C layer a new client has arrived */
+ if ((err = i2c_attach_client(new_client)))
+ {
+ kfree(data);
+ return err;
+ }
+ /* Initialize the PCF8574 chip */
+ max7311_init_client(new_client);
+
+ /* Register sysfs hooks */
+ device_create_file(&new_client->dev, &dev_attr_read);
+ device_create_file(&new_client->dev, &dev_attr_write);
+ device_create_file(&new_client->dev, &dev_attr_config);
+ device_create_file(&new_client->dev, &dev_attr_polarity);
+ return 0;
+}
+
+static int max7311_detach_client(struct i2c_client *client)
+{
+ int err;
+ struct max7311_data *data = i2c_get_clientdata(client);
+
+ if ((err = i2c_detach_client(client)))
+ {
+ return err;
+ }
+ list_del(&data->list);
+ kfree(data);
+ return 0;
+}
+
+/* Called when we have found a new MAX7311. */
+static void max7311_init_client(struct i2c_client *client)
+{
+ struct max7311_data *data = i2c_get_clientdata(client);
+ //Default all ports to inputs!
+ data->config = i2c_smbus_read_word_data(client,REG_CONFIG);
+ data->output = i2c_smbus_read_word_data(client,REG_OUTPUT);
+ data->polarity = i2c_smbus_read_word_data(client,REG_POLARITY);
+ //Enable bus timeout
+ i2c_smbus_write_byte_data(client,REG_TIMEOUT,0x01);
+ //Register with our list
+ INIT_LIST_HEAD(&data->list);
+ list_add_tail(&data->list, &max7311_clients);
+}
+
+struct max7311_data * get_max7311_client(int bus, int address)
+{
+ struct list_head *walk;
+ struct list_head *tmp;
+ struct max7311_data *data;
+
+ list_for_each_safe(walk, tmp, &max7311_clients) {
+ data = list_entry(walk, struct max7311_data, list);
+ if ((data->client.adapter->nr == bus)&&(data->client.addr==address))
+ return data;
+ }
+ return NULL;
+}
+
+static int do_max7311_write(int bus, int address, int chipReg, int newData)
+{
+ struct max7311_data *data;
+ if((data=get_max7311_client(bus,address)))
+ {
+ switch(chipReg) {
+ case REG_OUTPUT:
+ {
+ data->output = newData;
+ return i2c_smbus_write_word_data(&data->client,REG_OUTPUT,newData);
+ } break;
+ case REG_POLARITY:
+ {
+ data->polarity = newData;
+ return
i2c_smbus_write_word_data(&data->client,REG_POLARITY,newData);
+ } break;
+ case REG_CONFIG:
+ {
+ data->config = newData;
+ return i2c_smbus_write_word_data(&data->client,REG_CONFIG,newData);
+ }
+ default:
+ {
+ return -1;
+ }
+ }
+ } else {
+ return -ENODEV;
+ }
+}
+static int do_max7311_read(int bus, int address, int chipReg)
+{
+ struct max7311_data *data;
+ if((data=get_max7311_client(bus,address)))
+ {
+ switch(chipReg) {
+ case REG_INPUT:
+ {
+ return i2c_smbus_read_word_data(&data->client,REG_INPUT);
+ } break;
+ case REG_OUTPUT:
+ {
+ return data->output;
+ } break;
+ case REG_POLARITY:
+ {
+ return data->polarity;
+ } break;
+ case REG_CONFIG:
+ {
+ return data->config;
+ }
+ default:
+ {
+ return -1;
+ }
+ }
+ } else {
+ return -ENODEV;
+ }
+}
+
+static int __init max7311_init(void)
+{
+ int i;
+ unsigned short addr;
+ char *all_addr = CONFIG_SENSORS_MAX7311_ADDRESSES;
+ for(i=0; i<CONFIG_SENSORS_MAX7311_NUMCLIENTS; i++) {
+ addr = simple_strtoul(all_addr,&all_addr,16);
+ if(all_addr[0]!='\0') {
+ all_addr++;
+ }
+ if(addr)
+ {
+ normal_i2c[i] = addr;
+ } else {
+ normal_i2c[i] = I2C_CLIENT_END;
+ }
+ }
+ return i2c_add_driver(&max7311_driver);
+}
+
+static void __exit max7311_exit(void)
+{
+ i2c_del_driver(&max7311_driver);
+}
+
+
+MODULE_AUTHOR("Walter Goossens <walter.goossens at axon.tv>");
+MODULE_DESCRIPTION("MAX7311 driver");
+MODULE_LICENSE("GPL");
+
+EXPORT_SYMBOL(do_max7311_read);
+EXPORT_SYMBOL(do_max7311_write);
+
+module_init(max7311_init);
+module_exit(max7311_exit);
