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-rw-r--r--drivers/i2c/i2c-core.c1272
1 files changed, 1272 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
new file mode 100644
index 000000000000..9011627d7eb0
--- /dev/null
+++ b/drivers/i2c/i2c-core.c
@@ -0,0 +1,1272 @@
+/* i2c-core.c - a device driver for the iic-bus interface */
+/* ------------------------------------------------------------------------- */
+/* Copyright (C) 1995-99 Simon G. Vogl
+
+ 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. */
+/* ------------------------------------------------------------------------- */
+
+/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>.
+ All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl>
+ SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/idr.h>
+#include <linux/seq_file.h>
+#include <asm/uaccess.h>
+
+
+static LIST_HEAD(adapters);
+static LIST_HEAD(drivers);
+static DECLARE_MUTEX(core_lists);
+static DEFINE_IDR(i2c_adapter_idr);
+
+/* match always succeeds, as we want the probe() to tell if we really accept this match */
+static int i2c_device_match(struct device *dev, struct device_driver *drv)
+{
+ return 1;
+}
+
+static int i2c_bus_suspend(struct device * dev, pm_message_t state)
+{
+ int rc = 0;
+
+ if (dev->driver && dev->driver->suspend)
+ rc = dev->driver->suspend(dev,state,0);
+ return rc;
+}
+
+static int i2c_bus_resume(struct device * dev)
+{
+ int rc = 0;
+
+ if (dev->driver && dev->driver->resume)
+ rc = dev->driver->resume(dev,0);
+ return rc;
+}
+
+static struct bus_type i2c_bus_type = {
+ .name = "i2c",
+ .match = i2c_device_match,
+ .suspend = i2c_bus_suspend,
+ .resume = i2c_bus_resume,
+};
+
+static int i2c_device_probe(struct device *dev)
+{
+ return -ENODEV;
+}
+
+static int i2c_device_remove(struct device *dev)
+{
+ return 0;
+}
+
+static void i2c_adapter_dev_release(struct device *dev)
+{
+ struct i2c_adapter *adap = dev_to_i2c_adapter(dev);
+ complete(&adap->dev_released);
+}
+
+static struct device_driver i2c_adapter_driver = {
+ .name = "i2c_adapter",
+ .bus = &i2c_bus_type,
+ .probe = i2c_device_probe,
+ .remove = i2c_device_remove,
+};
+
+static void i2c_adapter_class_dev_release(struct class_device *dev)
+{
+ struct i2c_adapter *adap = class_dev_to_i2c_adapter(dev);
+ complete(&adap->class_dev_released);
+}
+
+static struct class i2c_adapter_class = {
+ .name = "i2c-adapter",
+ .release = &i2c_adapter_class_dev_release,
+};
+
+static ssize_t show_adapter_name(struct device *dev, char *buf)
+{
+ struct i2c_adapter *adap = dev_to_i2c_adapter(dev);
+ return sprintf(buf, "%s\n", adap->name);
+}
+static DEVICE_ATTR(name, S_IRUGO, show_adapter_name, NULL);
+
+
+static void i2c_client_release(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ complete(&client->released);
+}
+
+static ssize_t show_client_name(struct device *dev, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ return sprintf(buf, "%s\n", client->name);
+}
+
+/*
+ * We can't use the DEVICE_ATTR() macro here as we want the same filename for a
+ * different type of a device. So beware if the DEVICE_ATTR() macro ever
+ * changes, this definition will also have to change.
+ */
+static struct device_attribute dev_attr_client_name = {
+ .attr = {.name = "name", .mode = S_IRUGO, .owner = THIS_MODULE },
+ .show = &show_client_name,
+};
+
+
+/* ---------------------------------------------------
+ * registering functions
+ * ---------------------------------------------------
+ */
+
+/* -----
+ * i2c_add_adapter is called from within the algorithm layer,
+ * when a new hw adapter registers. A new device is register to be
+ * available for clients.
+ */
+int i2c_add_adapter(struct i2c_adapter *adap)
+{
+ int id, res = 0;
+ struct list_head *item;
+ struct i2c_driver *driver;
+
+ down(&core_lists);
+
+ if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) {
+ res = -ENOMEM;
+ goto out_unlock;
+ }
+
+ res = idr_get_new(&i2c_adapter_idr, NULL, &id);
+ if (res < 0) {
+ if (res == -EAGAIN)
+ res = -ENOMEM;
+ goto out_unlock;
+ }
+
+ adap->nr = id & MAX_ID_MASK;
+ init_MUTEX(&adap->bus_lock);
+ init_MUTEX(&adap->clist_lock);
+ list_add_tail(&adap->list,&adapters);
+ INIT_LIST_HEAD(&adap->clients);
+
+ /* Add the adapter to the driver core.
+ * If the parent pointer is not set up,
+ * we add this adapter to the host bus.
+ */
+ if (adap->dev.parent == NULL)
+ adap->dev.parent = &platform_bus;
+ sprintf(adap->dev.bus_id, "i2c-%d", adap->nr);
+ adap->dev.driver = &i2c_adapter_driver;
+ adap->dev.release = &i2c_adapter_dev_release;
+ device_register(&adap->dev);
+ device_create_file(&adap->dev, &dev_attr_name);
+
+ /* Add this adapter to the i2c_adapter class */
+ memset(&adap->class_dev, 0x00, sizeof(struct class_device));
+ adap->class_dev.dev = &adap->dev;
+ adap->class_dev.class = &i2c_adapter_class;
+ strlcpy(adap->class_dev.class_id, adap->dev.bus_id, BUS_ID_SIZE);
+ class_device_register(&adap->class_dev);
+
+ /* inform drivers of new adapters */
+ list_for_each(item,&drivers) {
+ driver = list_entry(item, struct i2c_driver, list);
+ if (driver->flags & I2C_DF_NOTIFY)
+ /* We ignore the return code; if it fails, too bad */
+ driver->attach_adapter(adap);
+ }
+
+ dev_dbg(&adap->dev, "registered as adapter #%d\n", adap->nr);
+
+out_unlock:
+ up(&core_lists);
+ return res;
+}
+
+
+int i2c_del_adapter(struct i2c_adapter *adap)
+{
+ struct list_head *item, *_n;
+ struct i2c_adapter *adap_from_list;
+ struct i2c_driver *driver;
+ struct i2c_client *client;
+ int res = 0;
+
+ down(&core_lists);
+
+ /* First make sure that this adapter was ever added */
+ list_for_each_entry(adap_from_list, &adapters, list) {
+ if (adap_from_list == adap)
+ break;
+ }
+ if (adap_from_list != adap) {
+ pr_debug("I2C: Attempting to delete an unregistered "
+ "adapter\n");
+ res = -EINVAL;
+ goto out_unlock;
+ }
+
+ list_for_each(item,&drivers) {
+ driver = list_entry(item, struct i2c_driver, list);
+ if (driver->detach_adapter)
+ if ((res = driver->detach_adapter(adap))) {
+ dev_warn(&adap->dev, "can't detach adapter "
+ "while detaching driver %s: driver not "
+ "detached!", driver->name);
+ goto out_unlock;
+ }
+ }
+
+ /* detach any active clients. This must be done first, because
+ * it can fail; in which case we give upp. */
+ list_for_each_safe(item, _n, &adap->clients) {
+ client = list_entry(item, struct i2c_client, list);
+
+ /* detaching devices is unconditional of the set notify
+ * flag, as _all_ clients that reside on the adapter
+ * must be deleted, as this would cause invalid states.
+ */
+ if ((res=client->driver->detach_client(client))) {
+ dev_err(&adap->dev, "adapter not "
+ "unregistered, because client at "
+ "address %02x can't be detached. ",
+ client->addr);
+ goto out_unlock;
+ }
+ }
+
+ /* clean up the sysfs representation */
+ init_completion(&adap->dev_released);
+ init_completion(&adap->class_dev_released);
+ class_device_unregister(&adap->class_dev);
+ device_remove_file(&adap->dev, &dev_attr_name);
+ device_unregister(&adap->dev);
+ list_del(&adap->list);
+
+ /* wait for sysfs to drop all references */
+ wait_for_completion(&adap->dev_released);
+ wait_for_completion(&adap->class_dev_released);
+
+ /* free dynamically allocated bus id */
+ idr_remove(&i2c_adapter_idr, adap->nr);
+
+ dev_dbg(&adap->dev, "adapter unregistered\n");
+
+ out_unlock:
+ up(&core_lists);
+ return res;
+}
+
+
+/* -----
+ * What follows is the "upwards" interface: commands for talking to clients,
+ * which implement the functions to access the physical information of the
+ * chips.
+ */
+
+int i2c_add_driver(struct i2c_driver *driver)
+{
+ struct list_head *item;
+ struct i2c_adapter *adapter;
+ int res = 0;
+
+ down(&core_lists);
+
+ /* add the driver to the list of i2c drivers in the driver core */
+ driver->driver.name = driver->name;
+ driver->driver.bus = &i2c_bus_type;
+ driver->driver.probe = i2c_device_probe;
+ driver->driver.remove = i2c_device_remove;
+
+ res = driver_register(&driver->driver);
+ if (res)
+ goto out_unlock;
+
+ list_add_tail(&driver->list,&drivers);
+ pr_debug("i2c-core: driver %s registered.\n", driver->name);
+
+ /* now look for instances of driver on our adapters */
+ if (driver->flags & I2C_DF_NOTIFY) {
+ list_for_each(item,&adapters) {
+ adapter = list_entry(item, struct i2c_adapter, list);
+ driver->attach_adapter(adapter);
+ }
+ }
+
+ out_unlock:
+ up(&core_lists);
+ return res;
+}
+
+int i2c_del_driver(struct i2c_driver *driver)
+{
+ struct list_head *item1, *item2, *_n;
+ struct i2c_client *client;
+ struct i2c_adapter *adap;
+
+ int res = 0;
+
+ down(&core_lists);
+
+ /* Have a look at each adapter, if clients of this driver are still
+ * attached. If so, detach them to be able to kill the driver
+ * afterwards.
+ */
+ pr_debug("i2c-core: unregister_driver - looking for clients.\n");
+ /* removing clients does not depend on the notify flag, else
+ * invalid operation might (will!) result, when using stale client
+ * pointers.
+ */
+ list_for_each(item1,&adapters) {
+ adap = list_entry(item1, struct i2c_adapter, list);
+ dev_dbg(&adap->dev, "examining adapter\n");
+ if (driver->detach_adapter) {
+ if ((res = driver->detach_adapter(adap))) {
+ dev_warn(&adap->dev, "while unregistering "
+ "dummy driver %s, adapter could "
+ "not be detached properly; driver "
+ "not unloaded!",driver->name);
+ goto out_unlock;
+ }
+ } else {
+ list_for_each_safe(item2, _n, &adap->clients) {
+ client = list_entry(item2, struct i2c_client, list);
+ if (client->driver != driver)
+ continue;
+ pr_debug("i2c-core.o: detaching client %s:\n", client->name);
+ if ((res = driver->detach_client(client))) {
+ dev_err(&adap->dev, "while "
+ "unregistering driver "
+ "`%s', the client at "
+ "address %02x of "
+ "adapter could not "
+ "be detached; driver "
+ "not unloaded!",
+ driver->name,
+ client->addr);
+ goto out_unlock;
+ }
+ }
+ }
+ }
+
+ driver_unregister(&driver->driver);
+ list_del(&driver->list);
+ pr_debug("i2c-core: driver unregistered: %s\n", driver->name);
+
+ out_unlock:
+ up(&core_lists);
+ return 0;
+}
+
+static int __i2c_check_addr(struct i2c_adapter *adapter, unsigned int addr)
+{
+ struct list_head *item;
+ struct i2c_client *client;
+
+ list_for_each(item,&adapter->clients) {
+ client = list_entry(item, struct i2c_client, list);
+ if (client->addr == addr)
+ return -EBUSY;
+ }
+ return 0;
+}
+
+int i2c_check_addr(struct i2c_adapter *adapter, int addr)
+{
+ int rval;
+
+ down(&adapter->clist_lock);
+ rval = __i2c_check_addr(adapter, addr);
+ up(&adapter->clist_lock);
+
+ return rval;
+}
+
+int i2c_attach_client(struct i2c_client *client)
+{
+ struct i2c_adapter *adapter = client->adapter;
+
+ down(&adapter->clist_lock);
+ if (__i2c_check_addr(client->adapter, client->addr)) {
+ up(&adapter->clist_lock);
+ return -EBUSY;
+ }
+ list_add_tail(&client->list,&adapter->clients);
+ up(&adapter->clist_lock);
+
+ if (adapter->client_register) {
+ if (adapter->client_register(client)) {
+ dev_warn(&adapter->dev, "warning: client_register "
+ "seems to have failed for client %02x\n",
+ client->addr);
+ }
+ }
+
+ dev_dbg(&adapter->dev, "client [%s] registered to adapter\n",
+ client->name);
+
+ if (client->flags & I2C_CLIENT_ALLOW_USE)
+ client->usage_count = 0;
+
+ client->dev.parent = &client->adapter->dev;
+ client->dev.driver = &client->driver->driver;
+ client->dev.bus = &i2c_bus_type;
+ client->dev.release = &i2c_client_release;
+
+ snprintf(&client->dev.bus_id[0], sizeof(client->dev.bus_id),
+ "%d-%04x", i2c_adapter_id(adapter), client->addr);
+ pr_debug("registering %s\n", client->dev.bus_id);
+ device_register(&client->dev);
+ device_create_file(&client->dev, &dev_attr_client_name);
+
+ return 0;
+}
+
+
+int i2c_detach_client(struct i2c_client *client)
+{
+ struct i2c_adapter *adapter = client->adapter;
+ int res = 0;
+
+ if ((client->flags & I2C_CLIENT_ALLOW_USE) && (client->usage_count > 0))
+ return -EBUSY;
+
+ if (adapter->client_unregister) {
+ res = adapter->client_unregister(client);
+ if (res) {
+ dev_err(&client->dev,
+ "client_unregister [%s] failed, "
+ "client not detached", client->name);
+ goto out;
+ }
+ }
+
+ down(&adapter->clist_lock);
+ list_del(&client->list);
+ init_completion(&client->released);
+ device_remove_file(&client->dev, &dev_attr_client_name);
+ device_unregister(&client->dev);
+ up(&adapter->clist_lock);
+ wait_for_completion(&client->released);
+
+ out:
+ return res;
+}
+
+static int i2c_inc_use_client(struct i2c_client *client)
+{
+
+ if (!try_module_get(client->driver->owner))
+ return -ENODEV;
+ if (!try_module_get(client->adapter->owner)) {
+ module_put(client->driver->owner);
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static void i2c_dec_use_client(struct i2c_client *client)
+{
+ module_put(client->driver->owner);
+ module_put(client->adapter->owner);
+}
+
+int i2c_use_client(struct i2c_client *client)
+{
+ int ret;
+
+ ret = i2c_inc_use_client(client);
+ if (ret)
+ return ret;
+
+ if (client->flags & I2C_CLIENT_ALLOW_USE) {
+ if (client->flags & I2C_CLIENT_ALLOW_MULTIPLE_USE)
+ client->usage_count++;
+ else if (client->usage_count > 0)
+ goto busy;
+ else
+ client->usage_count++;
+ }
+
+ return 0;
+ busy:
+ i2c_dec_use_client(client);
+ return -EBUSY;
+}
+
+int i2c_release_client(struct i2c_client *client)
+{
+ if(client->flags & I2C_CLIENT_ALLOW_USE) {
+ if(client->usage_count>0)
+ client->usage_count--;
+ else {
+ pr_debug("i2c-core: %s used one too many times\n",
+ __FUNCTION__);
+ return -EPERM;
+ }
+ }
+
+ i2c_dec_use_client(client);
+
+ return 0;
+}
+
+void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg)
+{
+ struct list_head *item;
+ struct i2c_client *client;
+
+ down(&adap->clist_lock);
+ list_for_each(item,&adap->clients) {
+ client = list_entry(item, struct i2c_client, list);
+ if (!try_module_get(client->driver->owner))
+ continue;
+ if (NULL != client->driver->command) {
+ up(&adap->clist_lock);
+ client->driver->command(client,cmd,arg);
+ down(&adap->clist_lock);
+ }
+ module_put(client->driver->owner);
+ }
+ up(&adap->clist_lock);
+}
+
+static int __init i2c_init(void)
+{
+ int retval;
+
+ retval = bus_register(&i2c_bus_type);
+ if (retval)
+ return retval;
+ retval = driver_register(&i2c_adapter_driver);
+ if (retval)
+ return retval;
+ return class_register(&i2c_adapter_class);
+}
+
+static void __exit i2c_exit(void)
+{
+ class_unregister(&i2c_adapter_class);
+ driver_unregister(&i2c_adapter_driver);
+ bus_unregister(&i2c_bus_type);
+}
+
+subsys_initcall(i2c_init);
+module_exit(i2c_exit);
+
+/* ----------------------------------------------------
+ * the functional interface to the i2c busses.
+ * ----------------------------------------------------
+ */
+
+int i2c_transfer(struct i2c_adapter * adap, struct i2c_msg *msgs, int num)
+{
+ int ret;
+
+ if (adap->algo->master_xfer) {
+#ifdef DEBUG
+ for (ret = 0; ret < num; ret++) {
+ dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, "
+ "len=%d\n", ret, msgs[ret].flags & I2C_M_RD ?
+ 'R' : 'W', msgs[ret].addr, msgs[ret].len);
+ }
+#endif
+
+ down(&adap->bus_lock);
+ ret = adap->algo->master_xfer(adap,msgs,num);
+ up(&adap->bus_lock);
+
+ return ret;
+ } else {
+ dev_dbg(&adap->dev, "I2C level transfers not supported\n");
+ return -ENOSYS;
+ }
+}
+
+int i2c_master_send(struct i2c_client *client,const char *buf ,int count)
+{
+ int ret;
+ struct i2c_adapter *adap=client->adapter;
+ struct i2c_msg msg;
+
+ if (client->adapter->algo->master_xfer) {
+ msg.addr = client->addr;
+ msg.flags = client->flags & I2C_M_TEN;
+ msg.len = count;
+ msg.buf = (char *)buf;
+
+ dev_dbg(&client->adapter->dev, "master_send: writing %d bytes.\n",
+ count);
+
+ down(&adap->bus_lock);
+ ret = adap->algo->master_xfer(adap,&msg,1);
+ up(&adap->bus_lock);
+
+ /* if everything went ok (i.e. 1 msg transmitted), return #bytes
+ * transmitted, else error code.
+ */
+ return (ret == 1 )? count : ret;
+ } else {
+ dev_err(&client->adapter->dev, "I2C level transfers not supported\n");
+ return -ENOSYS;
+ }
+}
+
+int i2c_master_recv(struct i2c_client *client, char *buf ,int count)
+{
+ struct i2c_adapter *adap=client->adapter;
+ struct i2c_msg msg;
+ int ret;
+ if (client->adapter->algo->master_xfer) {
+ msg.addr = client->addr;
+ msg.flags = client->flags & I2C_M_TEN;
+ msg.flags |= I2C_M_RD;
+ msg.len = count;
+ msg.buf = buf;
+
+ dev_dbg(&client->adapter->dev, "master_recv: reading %d bytes.\n",
+ count);
+
+ down(&adap->bus_lock);
+ ret = adap->algo->master_xfer(adap,&msg,1);
+ up(&adap->bus_lock);
+
+ dev_dbg(&client->adapter->dev, "master_recv: return:%d (count:%d, addr:0x%02x)\n",
+ ret, count, client->addr);
+
+ /* if everything went ok (i.e. 1 msg transmitted), return #bytes
+ * transmitted, else error code.
+ */
+ return (ret == 1 )? count : ret;
+ } else {
+ dev_err(&client->adapter->dev, "I2C level transfers not supported\n");
+ return -ENOSYS;
+ }
+}
+
+
+int i2c_control(struct i2c_client *client,
+ unsigned int cmd, unsigned long arg)
+{
+ int ret = 0;
+ struct i2c_adapter *adap = client->adapter;
+
+ dev_dbg(&client->adapter->dev, "i2c ioctl, cmd: 0x%x, arg: %#lx\n", cmd, arg);
+ switch (cmd) {
+ case I2C_RETRIES:
+ adap->retries = arg;
+ break;
+ case I2C_TIMEOUT:
+ adap->timeout = arg;
+ break;
+ default:
+ if (adap->algo->algo_control!=NULL)
+ ret = adap->algo->algo_control(adap,cmd,arg);
+ }
+ return ret;
+}
+
+/* ----------------------------------------------------
+ * the i2c address scanning function
+ * Will not work for 10-bit addresses!
+ * ----------------------------------------------------
+ */
+int i2c_probe(struct i2c_adapter *adapter,
+ struct i2c_client_address_data *address_data,
+ int (*found_proc) (struct i2c_adapter *, int, int))
+{
+ int addr,i,found,err;
+ int adap_id = i2c_adapter_id(adapter);
+
+ /* Forget it if we can't probe using SMBUS_QUICK */
+ if (! i2c_check_functionality(adapter,I2C_FUNC_SMBUS_QUICK))
+ return -1;
+
+ for (addr = 0x00; addr <= 0x7f; addr++) {
+
+ /* Skip if already in use */
+ if (i2c_check_addr(adapter,addr))
+ continue;
+
+ /* If it is in one of the force entries, we don't do any detection
+ at all */
+ found = 0;
+
+ for (i = 0; !found && (address_data->force[i] != I2C_CLIENT_END); i += 2) {
+ if (((adap_id == address_data->force[i]) ||
+ (address_data->force[i] == ANY_I2C_BUS)) &&
+ (addr == address_data->force[i+1])) {
+ dev_dbg(&adapter->dev, "found force parameter for adapter %d, addr %04x\n",
+ adap_id, addr);
+ if ((err = found_proc(adapter,addr,0)))
+ return err;
+ found = 1;
+ }
+ }
+ if (found)
+ continue;
+
+ /* If this address is in one of the ignores, we can forget about
+ it right now */
+ for (i = 0;
+ !found && (address_data->ignore[i] != I2C_CLIENT_END);
+ i += 2) {
+ if (((adap_id == address_data->ignore[i]) ||
+ ((address_data->ignore[i] == ANY_I2C_BUS))) &&
+ (addr == address_data->ignore[i+1])) {
+ dev_dbg(&adapter->dev, "found ignore parameter for adapter %d, "
+ "addr %04x\n", adap_id ,addr);
+ found = 1;
+ }
+ }
+ for (i = 0;
+ !found && (address_data->ignore_range[i] != I2C_CLIENT_END);
+ i += 3) {
+ if (((adap_id == address_data->ignore_range[i]) ||
+ ((address_data->ignore_range[i]==ANY_I2C_BUS))) &&
+ (addr >= address_data->ignore_range[i+1]) &&
+ (addr <= address_data->ignore_range[i+2])) {
+ dev_dbg(&adapter->dev, "found ignore_range parameter for adapter %d, "
+ "addr %04x\n", adap_id,addr);
+ found = 1;
+ }
+ }
+ if (found)
+ continue;
+
+ /* Now, we will do a detection, but only if it is in the normal or
+ probe entries */
+ for (i = 0;
+ !found && (address_data->normal_i2c[i] != I2C_CLIENT_END);
+ i += 1) {
+ if (addr == address_data->normal_i2c[i]) {
+ found = 1;
+ dev_dbg(&adapter->dev, "found normal i2c entry for adapter %d, "
+ "addr %02x\n", adap_id, addr);
+ }
+ }
+
+ for (i = 0;
+ !found && (address_data->normal_i2c_range[i] != I2C_CLIENT_END);
+ i += 2) {
+ if ((addr >= address_data->normal_i2c_range[i]) &&
+ (addr <= address_data->normal_i2c_range[i+1])) {
+ found = 1;
+ dev_dbg(&adapter->dev, "found normal i2c_range entry for adapter %d, "
+ "addr %04x\n", adap_id,addr);
+ }
+ }
+
+ for (i = 0;
+ !found && (address_data->probe[i] != I2C_CLIENT_END);
+ i += 2) {
+ if (((adap_id == address_data->probe[i]) ||
+ ((address_data->probe[i] == ANY_I2C_BUS))) &&
+ (addr == address_data->probe[i+1])) {
+ found = 1;
+ dev_dbg(&adapter->dev, "found probe parameter for adapter %d, "
+ "addr %04x\n", adap_id,addr);
+ }
+ }
+ for (i = 0;
+ !found && (address_data->probe_range[i] != I2C_CLIENT_END);
+ i += 3) {
+ if (((adap_id == address_data->probe_range[i]) ||
+ (address_data->probe_range[i] == ANY_I2C_BUS)) &&
+ (addr >= address_data->probe_range[i+1]) &&
+ (addr <= address_data->probe_range[i+2])) {
+ found = 1;
+ dev_dbg(&adapter->dev, "found probe_range parameter for adapter %d, "
+ "addr %04x\n", adap_id,addr);
+ }
+ }
+ if (!found)
+ continue;
+
+ /* OK, so we really should examine this address. First check
+ whether there is some client here at all! */
+ if (i2c_smbus_xfer(adapter,addr,0,0,0,I2C_SMBUS_QUICK,NULL) >= 0)
+ if ((err = found_proc(adapter,addr,-1)))
+ return err;
+ }
+ return 0;
+}
+
+/*
+ * return id number for a specific adapter
+ */
+int i2c_adapter_id(struct i2c_adapter *adap)
+{
+ return adap->nr;
+}
+
+struct i2c_adapter* i2c_get_adapter(int id)
+{
+ struct list_head *item;
+ struct i2c_adapter *adapter;
+
+ down(&core_lists);
+ list_for_each(item,&adapters) {
+ adapter = list_entry(item, struct i2c_adapter, list);
+ if (id == adapter->nr &&
+ try_module_get(adapter->owner)) {
+ up(&core_lists);
+ return adapter;
+ }
+ }
+ up(&core_lists);
+ return NULL;
+}
+
+void i2c_put_adapter(struct i2c_adapter *adap)
+{
+ module_put(adap->owner);
+}
+
+/* The SMBus parts */
+
+#define POLY (0x1070U << 3)
+static u8
+crc8(u16 data)
+{
+ int i;
+
+ for(i = 0; i < 8; i++) {
+ if (data & 0x8000)
+ data = data ^ POLY;
+ data = data << 1;
+ }
+ return (u8)(data >> 8);
+}
+
+/* CRC over count bytes in the first array plus the bytes in the rest
+ array if it is non-null. rest[0] is the (length of rest) - 1
+ and is included. */
+static u8 i2c_smbus_partial_pec(u8 crc, int count, u8 *first, u8 *rest)
+{
+ int i;
+
+ for(i = 0; i < count; i++)
+ crc = crc8((crc ^ first[i]) << 8);
+ if(rest != NULL)
+ for(i = 0; i <= rest[0]; i++)
+ crc = crc8((crc ^ rest[i]) << 8);
+ return crc;
+}
+
+static u8 i2c_smbus_pec(int count, u8 *first, u8 *rest)
+{
+ return i2c_smbus_partial_pec(0, count, first, rest);
+}
+
+/* Returns new "size" (transaction type)
+ Note that we convert byte to byte_data and byte_data to word_data
+ rather than invent new xxx_PEC transactions. */
+static int i2c_smbus_add_pec(u16 addr, u8 command, int size,
+ union i2c_smbus_data *data)
+{
+ u8 buf[3];
+
+ buf[0] = addr << 1;
+ buf[1] = command;
+ switch(size) {
+ case I2C_SMBUS_BYTE:
+ data->byte = i2c_smbus_pec(2, buf, NULL);
+ size = I2C_SMBUS_BYTE_DATA;
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ buf[2] = data->byte;
+ data->word = buf[2] ||
+ (i2c_smbus_pec(3, buf, NULL) << 8);
+ size = I2C_SMBUS_WORD_DATA;
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ /* unsupported */
+ break;
+ case I2C_SMBUS_BLOCK_DATA:
+ data->block[data->block[0] + 1] =
+ i2c_smbus_pec(2, buf, data->block);
+ size = I2C_SMBUS_BLOCK_DATA_PEC;
+ break;
+ }
+ return size;
+}
+
+static int i2c_smbus_check_pec(u16 addr, u8 command, int size, u8 partial,
+ union i2c_smbus_data *data)
+{
+ u8 buf[3], rpec, cpec;
+
+ buf[1] = command;
+ switch(size) {
+ case I2C_SMBUS_BYTE_DATA:
+ buf[0] = (addr << 1) | 1;
+ cpec = i2c_smbus_pec(2, buf, NULL);
+ rpec = data->byte;
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ buf[0] = (addr << 1) | 1;
+ buf[2] = data->word & 0xff;
+ cpec = i2c_smbus_pec(3, buf, NULL);
+ rpec = data->word >> 8;
+ break;
+ case I2C_SMBUS_WORD_DATA_PEC:
+ /* unsupported */
+ cpec = rpec = 0;
+ break;
+ case I2C_SMBUS_PROC_CALL_PEC:
+ /* unsupported */
+ cpec = rpec = 0;
+ break;
+ case I2C_SMBUS_BLOCK_DATA_PEC:
+ buf[0] = (addr << 1);
+ buf[2] = (addr << 1) | 1;
+ cpec = i2c_smbus_pec(3, buf, data->block);
+ rpec = data->block[data->block[0] + 1];
+ break;
+ case I2C_SMBUS_BLOCK_PROC_CALL_PEC:
+ buf[0] = (addr << 1) | 1;
+ rpec = i2c_smbus_partial_pec(partial, 1,
+ buf, data->block);
+ cpec = data->block[data->block[0] + 1];
+ break;
+ default:
+ cpec = rpec = 0;
+ break;
+ }
+ if (rpec != cpec) {
+ pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n",
+ rpec, cpec);
+ return -1;
+ }
+ return 0;
+}
+
+s32 i2c_smbus_write_quick(struct i2c_client *client, u8 value)
+{
+ return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ value,0,I2C_SMBUS_QUICK,NULL);
+}
+
+s32 i2c_smbus_read_byte(struct i2c_client *client)
+{
+ union i2c_smbus_data data;
+ if (i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ I2C_SMBUS_READ,0,I2C_SMBUS_BYTE, &data))
+ return -1;
+ else
+ return 0x0FF & data.byte;
+}
+
+s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value)
+{
+ union i2c_smbus_data data; /* only for PEC */
+ return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ I2C_SMBUS_WRITE,value, I2C_SMBUS_BYTE,&data);
+}
+
+s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command)
+{
+ union i2c_smbus_data data;
+ if (i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ I2C_SMBUS_READ,command, I2C_SMBUS_BYTE_DATA,&data))
+ return -1;
+ else
+ return 0x0FF & data.byte;
+}
+
+s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value)
+{
+ union i2c_smbus_data data;
+ data.byte = value;
+ return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ I2C_SMBUS_WRITE,command,
+ I2C_SMBUS_BYTE_DATA,&data);
+}
+
+s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command)
+{
+ union i2c_smbus_data data;
+ if (i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ I2C_SMBUS_READ,command, I2C_SMBUS_WORD_DATA, &data))
+ return -1;
+ else
+ return 0x0FFFF & data.word;
+}
+
+s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value)
+{
+ union i2c_smbus_data data;
+ data.word = value;
+ return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ I2C_SMBUS_WRITE,command,
+ I2C_SMBUS_WORD_DATA,&data);
+}
+
+s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command,
+ u8 length, u8 *values)
+{
+ union i2c_smbus_data data;
+ int i;
+ if (length > I2C_SMBUS_BLOCK_MAX)
+ length = I2C_SMBUS_BLOCK_MAX;
+ for (i = 1; i <= length; i++)
+ data.block[i] = values[i-1];
+ data.block[0] = length;
+ return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ I2C_SMBUS_WRITE,command,
+ I2C_SMBUS_BLOCK_DATA,&data);
+}
+
+/* Returns the number of read bytes */
+s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, u8 *values)
+{
+ union i2c_smbus_data data;
+ int i;
+ if (i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ I2C_SMBUS_READ,command,
+ I2C_SMBUS_I2C_BLOCK_DATA,&data))
+ return -1;
+ else {
+ for (i = 1; i <= data.block[0]; i++)
+ values[i-1] = data.block[i];
+ return data.block[0];
+ }
+}
+
+/* Simulate a SMBus command using the i2c protocol
+ No checking of parameters is done! */
+static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
+ unsigned short flags,
+ char read_write, u8 command, int size,
+ union i2c_smbus_data * data)
+{
+ /* So we need to generate a series of msgs. In the case of writing, we
+ need to use only one message; when reading, we need two. We initialize
+ most things with sane defaults, to keep the code below somewhat
+ simpler. */
+ unsigned char msgbuf0[34];
+ unsigned char msgbuf1[34];
+ int num = read_write == I2C_SMBUS_READ?2:1;
+ struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 },
+ { addr, flags | I2C_M_RD, 0, msgbuf1 }
+ };
+ int i;
+
+ msgbuf0[0] = command;
+ switch(size) {
+ case I2C_SMBUS_QUICK:
+ msg[0].len = 0;
+ /* Special case: The read/write field is used as data */
+ msg[0].flags = flags | (read_write==I2C_SMBUS_READ)?I2C_M_RD:0;
+ num = 1;
+ break;
+ case I2C_SMBUS_BYTE:
+ if (read_write == I2C_SMBUS_READ) {
+ /* Special case: only a read! */
+ msg[0].flags = I2C_M_RD | flags;
+ num = 1;
+ }
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ if (read_write == I2C_SMBUS_READ)
+ msg[1].len = 1;
+ else {
+ msg[0].len = 2;
+ msgbuf0[1] = data->byte;
+ }
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ if (read_write == I2C_SMBUS_READ)
+ msg[1].len = 2;
+ else {
+ msg[0].len=3;
+ msgbuf0[1] = data->word & 0xff;
+ msgbuf0[2] = (data->word >> 8) & 0xff;
+ }
+ break;
+ case I2C_SMBUS_PROC_CALL:
+ num = 2; /* Special case */
+ read_write = I2C_SMBUS_READ;
+ msg[0].len = 3;
+ msg[1].len = 2;
+ msgbuf0[1] = data->word & 0xff;
+ msgbuf0[2] = (data->word >> 8) & 0xff;
+ break;
+ case I2C_SMBUS_BLOCK_DATA:
+ case I2C_SMBUS_BLOCK_DATA_PEC:
+ if (read_write == I2C_SMBUS_READ) {
+ dev_err(&adapter->dev, "Block read not supported "
+ "under I2C emulation!\n");
+ return -1;
+ } else {
+ msg[0].len = data->block[0] + 2;
+ if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) {
+ dev_err(&adapter->dev, "smbus_access called with "
+ "invalid block write size (%d)\n",
+ data->block[0]);
+ return -1;
+ }
+ if(size == I2C_SMBUS_BLOCK_DATA_PEC)
+ (msg[0].len)++;
+ for (i = 1; i <= msg[0].len; i++)
+ msgbuf0[i] = data->block[i-1];
+ }
+ break;
+ case I2C_SMBUS_BLOCK_PROC_CALL:
+ case I2C_SMBUS_BLOCK_PROC_CALL_PEC:
+ dev_dbg(&adapter->dev, "Block process call not supported "
+ "under I2C emulation!\n");
+ return -1;
+ case I2C_SMBUS_I2C_BLOCK_DATA:
+ if (read_write == I2C_SMBUS_READ) {
+ msg[1].len = I2C_SMBUS_I2C_BLOCK_MAX;
+ } else {
+ msg[0].len = data->block[0] + 1;
+ if (msg[0].len > I2C_SMBUS_I2C_BLOCK_MAX + 1) {
+ dev_err(&adapter->dev, "i2c_smbus_xfer_emulated called with "
+ "invalid block write size (%d)\n",
+ data->block[0]);
+ return -1;
+ }
+ for (i = 1; i <= data->block[0]; i++)
+ msgbuf0[i] = data->block[i];
+ }
+ break;
+ default:
+ dev_err(&adapter->dev, "smbus_access called with invalid size (%d)\n",
+ size);
+ return -1;
+ }
+
+ if (i2c_transfer(adapter, msg, num) < 0)
+ return -1;
+
+ if (read_write == I2C_SMBUS_READ)
+ switch(size) {
+ case I2C_SMBUS_BYTE:
+ data->byte = msgbuf0[0];
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ data->byte = msgbuf1[0];
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ case I2C_SMBUS_PROC_CALL:
+ data->word = msgbuf1[0] | (msgbuf1[1] << 8);
+ break;
+ case I2C_SMBUS_I2C_BLOCK_DATA:
+ /* fixed at 32 for now */
+ data->block[0] = I2C_SMBUS_I2C_BLOCK_MAX;
+ for (i = 0; i < I2C_SMBUS_I2C_BLOCK_MAX; i++)
+ data->block[i+1] = msgbuf1[i];
+ break;
+ }
+ return 0;
+}
+
+
+s32 i2c_smbus_xfer(struct i2c_adapter * adapter, u16 addr, unsigned short flags,
+ char read_write, u8 command, int size,
+ union i2c_smbus_data * data)
+{
+ s32 res;
+ int swpec = 0;
+ u8 partial = 0;
+
+ flags &= I2C_M_TEN | I2C_CLIENT_PEC;
+ if((flags & I2C_CLIENT_PEC) &&
+ !(i2c_check_functionality(adapter, I2C_FUNC_SMBUS_HWPEC_CALC))) {
+ swpec = 1;
+ if(read_write == I2C_SMBUS_READ &&
+ size == I2C_SMBUS_BLOCK_DATA)
+ size = I2C_SMBUS_BLOCK_DATA_PEC;
+ else if(size == I2C_SMBUS_PROC_CALL)
+ size = I2C_SMBUS_PROC_CALL_PEC;
+ else if(size == I2C_SMBUS_BLOCK_PROC_CALL) {
+ i2c_smbus_add_pec(addr, command,
+ I2C_SMBUS_BLOCK_DATA, data);
+ partial = data->block[data->block[0] + 1];
+ size = I2C_SMBUS_BLOCK_PROC_CALL_PEC;
+ } else if(read_write == I2C_SMBUS_WRITE &&
+ size != I2C_SMBUS_QUICK &&
+ size != I2C_SMBUS_I2C_BLOCK_DATA)
+ size = i2c_smbus_add_pec(addr, command, size, data);
+ }
+
+ if (adapter->algo->smbus_xfer) {
+ down(&adapter->bus_lock);
+ res = adapter->algo->smbus_xfer(adapter,addr,flags,read_write,
+ command,size,data);
+ up(&adapter->bus_lock);
+ } else
+ res = i2c_smbus_xfer_emulated(adapter,addr,flags,read_write,
+ command,size,data);
+
+ if(res >= 0 && swpec &&
+ size != I2C_SMBUS_QUICK && size != I2C_SMBUS_I2C_BLOCK_DATA &&
+ (read_write == I2C_SMBUS_READ || size == I2C_SMBUS_PROC_CALL_PEC ||
+ size == I2C_SMBUS_BLOCK_PROC_CALL_PEC)) {
+ if(i2c_smbus_check_pec(addr, command, size, partial, data))
+ return -1;
+ }
+ return res;
+}
+
+
+EXPORT_SYMBOL(i2c_add_adapter);
+EXPORT_SYMBOL(i2c_del_adapter);
+EXPORT_SYMBOL(i2c_add_driver);
+EXPORT_SYMBOL(i2c_del_driver);
+EXPORT_SYMBOL(i2c_attach_client);
+EXPORT_SYMBOL(i2c_detach_client);
+EXPORT_SYMBOL(i2c_use_client);
+EXPORT_SYMBOL(i2c_release_client);
+EXPORT_SYMBOL(i2c_clients_command);
+EXPORT_SYMBOL(i2c_check_addr);
+
+EXPORT_SYMBOL(i2c_master_send);
+EXPORT_SYMBOL(i2c_master_recv);
+EXPORT_SYMBOL(i2c_control);
+EXPORT_SYMBOL(i2c_transfer);
+EXPORT_SYMBOL(i2c_adapter_id);
+EXPORT_SYMBOL(i2c_get_adapter);
+EXPORT_SYMBOL(i2c_put_adapter);
+EXPORT_SYMBOL(i2c_probe);
+
+EXPORT_SYMBOL(i2c_smbus_xfer);
+EXPORT_SYMBOL(i2c_smbus_write_quick);
+EXPORT_SYMBOL(i2c_smbus_read_byte);
+EXPORT_SYMBOL(i2c_smbus_write_byte);
+EXPORT_SYMBOL(i2c_smbus_read_byte_data);
+EXPORT_SYMBOL(i2c_smbus_write_byte_data);
+EXPORT_SYMBOL(i2c_smbus_read_word_data);
+EXPORT_SYMBOL(i2c_smbus_write_word_data);
+EXPORT_SYMBOL(i2c_smbus_write_block_data);
+EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data);
+
+MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
+MODULE_DESCRIPTION("I2C-Bus main module");
+MODULE_LICENSE("GPL");