I2C: add support for the PCF8575 chip.
Signed-off-by: Bart Van Assche (bart.vanassche at gmail.com)
diff -uprN -X orig/linux-2.6.22.9/Documentation/dontdiff orig/linux-2.6.22.9/drivers/i2c/chips/Kconfig linux-2.6.22.9/drivers/i2c/chips/Kconfig
--- orig/linux-2.6.22.9/drivers/i2c/chips/Kconfig 2007-09-26 20:03:01.000000000 +0200
+++ linux-2.6.22.9/drivers/i2c/chips/Kconfig 2007-10-05 09:27:19.000000000 +0200
@@ -41,13 +41,27 @@ config SENSORS_PCF8574
default n
help
If you say yes here you get support for Philips PCF8574 and
- PCF8574A chips.
+ 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.
- These devices are hard to detect and rarely found on mainstream
- hardware. If unsure, say N.
+ These devices are hard to detect automatically and are rarely found
+ on mainstream hardware. If unsure, say N.
+
+config SENSORS_PCF8575
+ tristate "Philips PCF8575"
+ default 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 device is hard to detect automatically and is rarely found on
+ mainstream hardware. If unsure, say N.
config SENSORS_PCA9539
tristate "Philips PCA9539 16-bit I/O port"
diff -uprN -X orig/linux-2.6.22.9/Documentation/dontdiff orig/linux-2.6.22.9/drivers/i2c/chips/Makefile linux-2.6.22.9/drivers/i2c/chips/Makefile
--- orig/linux-2.6.22.9/drivers/i2c/chips/Makefile 2007-09-26 20:03:01.000000000 +0200
+++ linux-2.6.22.9/drivers/i2c/chips/Makefile 2007-10-05 09:16:21.000000000 +0200
@@ -9,6 +9,7 @@ obj-$(CONFIG_SENSORS_MAX6875) += max6875
obj-$(CONFIG_SENSORS_M41T00) += m41t00.o
obj-$(CONFIG_SENSORS_PCA9539) += pca9539.o
obj-$(CONFIG_SENSORS_PCF8574) += pcf8574.o
+obj-$(CONFIG_SENSORS_PCF8575) += pcf8575.o
obj-$(CONFIG_SENSORS_PCF8591) += pcf8591.o
obj-$(CONFIG_ISP1301_OMAP) += isp1301_omap.o
obj-$(CONFIG_TPS65010) += tps65010.o
diff -uprN -X orig/linux-2.6.22.9/Documentation/dontdiff orig/linux-2.6.22.9/drivers/i2c/chips/pcf8575.c linux-2.6.22.9/drivers/i2c/chips/pcf8575.c
--- orig/linux-2.6.22.9/drivers/i2c/chips/pcf8575.c 2007-10-05 09:44:02.000000000 +0200
+++ linux-2.6.22.9/drivers/i2c/chips/pcf8575.c 2007-10-05 11:10:46.000000000 +0200
@@ -0,0 +1,305 @@
+/*
+ pcf8575.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>
+
+ Copyright (C) 2006 Michael Hennerich, Analog Devices Inc.
+ <hennerich at blackfin.uclinux.org>
+ based on the pcf8574.c
+
+ Ported from ucLinux to mainstream Linux kernel by Bart Van Assche.
+
+ About the pcf8575: the pcf8575 is an 16-bit I/O expander for the I2C bus
+ produced by a.o. Philips Semiconductors.
+
+ 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/version.h>
+#include <linux/i2c.h>
+
+
+/* Addresses to scan */
+static unsigned short normal_i2c[] = { I2C_CLIENT_END };
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 20)
+static unsigned short normal_i2c_range[] = { I2C_CLIENT_END };
+#endif
+
+/* Insmod parameters */
+I2C_CLIENT_INSMOD;
+
+
+/* Each client has this additional data */
+struct pcf8575_data {
+ struct i2c_client client;
+
+ u16 write; /* Remember last written value */
+ u8 buf[3];
+};
+
+static int pcf8575_attach_adapter(struct i2c_adapter *adapter);
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 0)
+static int pcf8575_detect(struct i2c_adapter *adapter, int address, int kind);
+#else
+static int pcf8575_detect(struct i2c_adapter *adapter,
+ int addr, unsigned short flags, int kind);
+#endif
+static int pcf8575_detach_client(struct i2c_client *client);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver pcf8575_driver = {
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "pcf8575",
+ },
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 0)
+ .owner = THIS_MODULE,
+ .name = "pcf8575",
+ .flags = I2C_DF_NOTIFY,
+#else
+#error
+#endif
+ .attach_adapter = pcf8575_attach_adapter,
+ .detach_client = pcf8575_detach_client,
+};
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 0)
+/* following are the sysfs callback functions */
+static ssize_t show_read(struct device *dev,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
+ struct device_attribute *attr,
+#endif
+ char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct pcf8575_data *data = i2c_get_clientdata(client);
+ unsigned short val;
+
+ i2c_master_recv(client, data->buf, 2);
+
+ val = data->buf[0];
+ val |= data->buf[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,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
+ struct device_attribute *attr,
+#endif
+ char *buf)
+{
+ struct pcf8575_data *data = i2c_get_clientdata(to_i2c_client(dev));
+ return sprintf(buf, "%u\n", data->write);
+}
+
+static ssize_t set_write(struct device *dev,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
+ struct device_attribute *attr,
+#endif
+ 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);
+
+ if (val > 0xffff)
+ return -EINVAL;
+
+ data->write = val;
+
+ data->buf[0] = val & 0xFF;
+ data->buf[1] = val >> 8;
+
+ i2c_master_send(client, data->buf, 2);
+
+ return count;
+}
+
+static DEVICE_ATTR(write, S_IWUSR | S_IRUGO, show_write, set_write);
+
+static ssize_t set_set_bit(struct device *dev,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
+ struct device_attribute *attr,
+#endif
+ 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);
+ unsigned short dummy;
+ if (val > 15)
+ return -EINVAL;
+
+ i2c_master_recv(client, data->buf, 2);
+
+ dummy = data->buf[0];
+ dummy |= data->buf[1]<<8;
+
+ dummy |= 1 << val;
+
+ data->buf[0] = dummy & 0xFF;
+ data->buf[1] = dummy >> 8;
+
+ i2c_master_send(client, data->buf, 2);
+
+ return count;
+}
+
+static DEVICE_ATTR(set_bit, S_IWUSR, show_write, set_set_bit);
+
+static ssize_t set_clear_bit(struct device *dev,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
+ struct device_attribute *attr,
+#endif
+ 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);
+ unsigned short dummy;
+ if (val > 15)
+ return -EINVAL;
+
+ i2c_master_recv(client, data->buf, 2);
+
+ dummy = data->buf[0];
+ dummy |= data->buf[1]<<8;
+
+ dummy &= ~(1 << val);
+
+ data->buf[0] = dummy & 0xFF;
+ data->buf[1] = dummy >> 8;
+
+ i2c_master_send(client, data->buf, 2);
+
+ return count;
+}
+
+static DEVICE_ATTR(clear_bit, S_IWUSR, show_write, set_clear_bit);
+#endif
+
+/*
+ * Real code
+ */
+
+static int pcf8575_attach_adapter(struct i2c_adapter *adapter)
+{
+ return i2c_probe(adapter, &addr_data, pcf8575_detect);
+}
+
+/* This function is called by i2c_probe */
+static int pcf8575_detect(struct i2c_adapter *adapter,
+ int address,
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 0)
+ unsigned short flags,
+#endif
+ int kind)
+{
+ struct i2c_client *new_client;
+ struct pcf8575_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. */
+ data = kzalloc(sizeof(struct pcf8575_data), GFP_KERNEL);
+ if (!data) {
+ 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 = &pcf8575_driver;
+ new_client->flags = 0;
+
+ /* Now, we would do the remaining detection. But the pcf8575 is plainly
+ impossible to detect! Stupid chip. */
+
+
+ client_name = "pcf8575";
+
+ /* Fill in the remaining client fields and put into the global list */
+ strlcpy(new_client->name, client_name, I2C_NAME_SIZE);
+
+ /* Tell the I2C layer a new client has arrived */
+ err = i2c_attach_client(new_client);
+ if (err)
+ goto exit_free;
+
+
+ /* Register sysfs hooks */
+ if (device_create_file(&new_client->dev, &dev_attr_read) >= 0
+ && device_create_file(&new_client->dev, &dev_attr_write) >= 0
+ && device_create_file(&new_client->dev, &dev_attr_set_bit) >= 0
+ && device_create_file(&new_client->dev, &dev_attr_clear_bit) >= 0) {
+ return 0;
+ }
+
+exit_free:
+ kfree(data);
+exit:
+ return err;
+}
+
+static int pcf8575_detach_client(struct i2c_client *client)
+{
+ int err;
+
+ err = i2c_detach_client(client);
+ if (err)
+ return err;
+
+ kfree(i2c_get_clientdata(client));
+ return 0;
+}
+
+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("Frodo Looijaard <frodol at dds.nl>, "
+ "Philip Edelbrock <phil at netroedge.com>, "
+ "Dan Eaton <dan.eaton at rocketlogix.com> "
+ "and Aurelien Jarno <aurelien at aurel32.net>"
+ "Michael Hennerich <hennerich at blackfin.uclinux.org>");
+MODULE_DESCRIPTION("pcf8575 driver");
+MODULE_LICENSE("GPL");
+
+module_init(pcf8575_init);
+module_exit(pcf8575_exit);
