/* 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> */
+ SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and
+ Jean Delvare <khali@linux-fr.org> */
-#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/idr.h>
#include <linux/seq_file.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/completion.h>
#include <asm/uaccess.h>
+#include "i2c-core.h"
+
static LIST_HEAD(adapters);
static LIST_HEAD(drivers);
-static DECLARE_MUTEX(core_lists);
+static DEFINE_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 */
+#define is_newstyle_driver(d) ((d)->probe || (d)->remove)
+
+/* ------------------------------------------------------------------------- */
+
static int i2c_device_match(struct device *dev, struct device_driver *drv)
{
- return 1;
-}
+ struct i2c_client *client = to_i2c_client(dev);
+ struct i2c_driver *driver = to_i2c_driver(drv);
-static int i2c_bus_suspend(struct device * dev, pm_message_t state)
-{
- int rc = 0;
+ /* make legacy i2c drivers bypass driver model probing entirely;
+ * such drivers scan each i2c adapter/bus themselves.
+ */
+ if (!is_newstyle_driver(driver))
+ return 0;
- if (dev->driver && dev->driver->suspend)
- rc = dev->driver->suspend(dev,state,0);
- return rc;
+ /* new style drivers use the same kind of driver matching policy
+ * as platform devices or SPI: compare device and driver IDs.
+ */
+ return strcmp(client->driver_name, drv->name) == 0;
}
-static int i2c_bus_resume(struct device * dev)
+#ifdef CONFIG_HOTPLUG
+
+/* uevent helps with hotplug: modprobe -q $(MODALIAS) */
+static int i2c_device_uevent(struct device *dev, char **envp, int num_envp,
+ char *buffer, int buffer_size)
{
- int rc = 0;
-
- if (dev->driver && dev->driver->resume)
- rc = dev->driver->resume(dev,0);
- return rc;
+ struct i2c_client *client = to_i2c_client(dev);
+ int i = 0, length = 0;
+
+ /* by definition, legacy drivers can't hotplug */
+ if (dev->driver || !client->driver_name)
+ return 0;
+
+ if (add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length,
+ "MODALIAS=%s", client->driver_name))
+ return -ENOMEM;
+ envp[i] = NULL;
+ dev_dbg(dev, "uevent\n");
+ return 0;
}
-static struct bus_type i2c_bus_type = {
- .name = "i2c",
- .match = i2c_device_match,
- .suspend = i2c_bus_suspend,
- .resume = i2c_bus_resume,
-};
+#else
+#define i2c_device_uevent NULL
+#endif /* CONFIG_HOTPLUG */
static int i2c_device_probe(struct device *dev)
{
- return -ENODEV;
+ struct i2c_client *client = to_i2c_client(dev);
+ struct i2c_driver *driver = to_i2c_driver(dev->driver);
+
+ if (!driver->probe)
+ return -ENODEV;
+ client->driver = driver;
+ dev_dbg(dev, "probe\n");
+ return driver->probe(client);
}
static int i2c_device_remove(struct device *dev)
{
- return 0;
+ struct i2c_client *client = to_i2c_client(dev);
+ struct i2c_driver *driver;
+ int status;
+
+ if (!dev->driver)
+ return 0;
+
+ driver = to_i2c_driver(dev->driver);
+ if (driver->remove) {
+ dev_dbg(dev, "remove\n");
+ status = driver->remove(client);
+ } else {
+ dev->driver = NULL;
+ status = 0;
+ }
+ if (status == 0)
+ client->driver = NULL;
+ return status;
}
-static void i2c_adapter_dev_release(struct device *dev)
+static void i2c_device_shutdown(struct device *dev)
{
- struct i2c_adapter *adap = dev_to_i2c_adapter(dev);
- complete(&adap->dev_released);
-}
+ struct i2c_driver *driver;
-static struct device_driver i2c_adapter_driver = {
- .name = "i2c_adapter",
- .bus = &i2c_bus_type,
- .probe = i2c_device_probe,
- .remove = i2c_device_remove,
-};
+ if (!dev->driver)
+ return;
+ driver = to_i2c_driver(dev->driver);
+ if (driver->shutdown)
+ driver->shutdown(to_i2c_client(dev));
+}
-static void i2c_adapter_class_dev_release(struct class_device *dev)
+static int i2c_device_suspend(struct device * dev, pm_message_t mesg)
{
- struct i2c_adapter *adap = class_dev_to_i2c_adapter(dev);
- complete(&adap->class_dev_released);
-}
+ struct i2c_driver *driver;
-static struct class i2c_adapter_class = {
- .name = "i2c-adapter",
- .release = &i2c_adapter_class_dev_release,
-};
+ if (!dev->driver)
+ return 0;
+ driver = to_i2c_driver(dev->driver);
+ if (!driver->suspend)
+ return 0;
+ return driver->suspend(to_i2c_client(dev), mesg);
+}
-static ssize_t show_adapter_name(struct device *dev, struct device_attribute *attr, char *buf)
+static int i2c_device_resume(struct device * dev)
{
- 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);
+ struct i2c_driver *driver;
+ if (!dev->driver)
+ return 0;
+ driver = to_i2c_driver(dev->driver);
+ if (!driver->resume)
+ return 0;
+ return driver->resume(to_i2c_client(dev));
+}
static void i2c_client_release(struct device *dev)
{
complete(&client->released);
}
+static void i2c_client_dev_release(struct device *dev)
+{
+ kfree(to_i2c_client(dev));
+}
+
static ssize_t show_client_name(struct device *dev, struct device_attribute *attr, 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,
-};
+static ssize_t show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ return client->driver_name
+ ? sprintf(buf, "%s\n", client->driver_name)
+ : 0;
+}
+static struct device_attribute i2c_dev_attrs[] = {
+ __ATTR(name, S_IRUGO, show_client_name, NULL),
+ /* modalias helps coldplug: modprobe $(cat .../modalias) */
+ __ATTR(modalias, S_IRUGO, show_modalias, NULL),
+ { },
+};
-/* ---------------------------------------------------
- * registering functions
- * ---------------------------------------------------
+struct bus_type i2c_bus_type = {
+ .name = "i2c",
+ .dev_attrs = i2c_dev_attrs,
+ .match = i2c_device_match,
+ .uevent = i2c_device_uevent,
+ .probe = i2c_device_probe,
+ .remove = i2c_device_remove,
+ .shutdown = i2c_device_shutdown,
+ .suspend = i2c_device_suspend,
+ .resume = i2c_device_resume,
+};
+EXPORT_SYMBOL_GPL(i2c_bus_type);
+
+/**
+ * i2c_new_device - instantiate an i2c device for use with a new style driver
+ * @adap: the adapter managing the device
+ * @info: describes one I2C device; bus_num is ignored
+ * Context: can sleep
+ *
+ * Create a device to work with a new style i2c driver, where binding is
+ * handled through driver model probe()/remove() methods. This call is not
+ * appropriate for use by mainboad initialization logic, which usually runs
+ * during an arch_initcall() long before any i2c_adapter could exist.
+ *
+ * This returns the new i2c client, which may be saved for later use with
+ * i2c_unregister_device(); or NULL to indicate an error.
*/
+struct i2c_client *
+i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info)
+{
+ struct i2c_client *client;
+ int status;
+
+ client = kzalloc(sizeof *client, GFP_KERNEL);
+ if (!client)
+ return NULL;
+
+ client->adapter = adap;
+
+ client->dev.platform_data = info->platform_data;
+ client->flags = info->flags;
+ client->addr = info->addr;
+ client->irq = info->irq;
+
+ strlcpy(client->driver_name, info->driver_name,
+ sizeof(client->driver_name));
+ strlcpy(client->name, info->type, sizeof(client->name));
-/* -----
- * 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.
+ /* a new style driver may be bound to this device when we
+ * return from this function, or any later moment (e.g. maybe
+ * hotplugging will load the driver module). and the device
+ * refcount model is the standard driver model one.
+ */
+ status = i2c_attach_client(client);
+ if (status < 0) {
+ kfree(client);
+ client = NULL;
+ }
+ return client;
+}
+EXPORT_SYMBOL_GPL(i2c_new_device);
+
+
+/**
+ * i2c_unregister_device - reverse effect of i2c_new_device()
+ * @client: value returned from i2c_new_device()
+ * Context: can sleep
*/
-int i2c_add_adapter(struct i2c_adapter *adap)
+void i2c_unregister_device(struct i2c_client *client)
{
- int id, res = 0;
- struct list_head *item;
- struct i2c_driver *driver;
+ struct i2c_adapter *adapter = client->adapter;
+ struct i2c_driver *driver = client->driver;
+
+ if (driver && !is_newstyle_driver(driver)) {
+ dev_err(&client->dev, "can't unregister devices "
+ "with legacy drivers\n");
+ WARN_ON(1);
+ return;
+ }
- down(&core_lists);
+ mutex_lock(&adapter->clist_lock);
+ list_del(&client->list);
+ mutex_unlock(&adapter->clist_lock);
- if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) {
- res = -ENOMEM;
- goto out_unlock;
- }
+ device_unregister(&client->dev);
+}
+EXPORT_SYMBOL_GPL(i2c_unregister_device);
- res = idr_get_new(&i2c_adapter_idr, NULL, &id);
- if (res < 0) {
- if (res == -EAGAIN)
- res = -ENOMEM;
- goto out_unlock;
+
+/* ------------------------------------------------------------------------- */
+
+/* I2C bus adapters -- one roots each I2C or SMBUS segment */
+
+void i2c_adapter_dev_release(struct device *dev)
+{
+ struct i2c_adapter *adap = to_i2c_adapter(dev);
+ complete(&adap->dev_released);
+}
+
+static ssize_t
+show_adapter_name(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct i2c_adapter *adap = to_i2c_adapter(dev);
+ return sprintf(buf, "%s\n", adap->name);
+}
+
+static struct device_attribute i2c_adapter_attrs[] = {
+ __ATTR(name, S_IRUGO, show_adapter_name, NULL),
+ { },
+};
+
+struct class i2c_adapter_class = {
+ .owner = THIS_MODULE,
+ .name = "i2c-adapter",
+ .dev_attrs = i2c_adapter_attrs,
+};
+
+static void i2c_scan_static_board_info(struct i2c_adapter *adapter)
+{
+ struct i2c_devinfo *devinfo;
+
+ mutex_lock(&__i2c_board_lock);
+ list_for_each_entry(devinfo, &__i2c_board_list, list) {
+ if (devinfo->busnum == adapter->nr
+ && !i2c_new_device(adapter,
+ &devinfo->board_info))
+ printk(KERN_ERR "i2c-core: can't create i2c%d-%04x\n",
+ i2c_adapter_id(adapter),
+ devinfo->board_info.addr);
}
+ mutex_unlock(&__i2c_board_lock);
+}
- adap->nr = id & MAX_ID_MASK;
- init_MUTEX(&adap->bus_lock);
- init_MUTEX(&adap->clist_lock);
- list_add_tail(&adap->list,&adapters);
+static int i2c_register_adapter(struct i2c_adapter *adap)
+{
+ int res = 0;
+ struct list_head *item;
+ struct i2c_driver *driver;
+
+ mutex_init(&adap->bus_lock);
+ mutex_init(&adap->clist_lock);
INIT_LIST_HEAD(&adap->clients);
+ mutex_lock(&core_lists);
+ list_add_tail(&adap->list, &adapters);
+
/* 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)
+ if (adap->dev.parent == NULL) {
adap->dev.parent = &platform_bus;
+ pr_debug("I2C adapter driver [%s] forgot to specify "
+ "physical device\n", adap->name);
+ }
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);
+ adap->dev.class = &i2c_adapter_class;
+ res = device_register(&adap->dev);
+ if (res)
+ goto out_list;
+
+ dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->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);
+ /* create pre-declared device nodes for new-style drivers */
+ if (adap->nr < __i2c_first_dynamic_bus_num)
+ i2c_scan_static_board_info(adap);
- /* inform drivers of new adapters */
+ /* let legacy drivers scan this bus for matching devices */
list_for_each(item,&drivers) {
driver = list_entry(item, struct i2c_driver, list);
- if (driver->flags & I2C_DF_NOTIFY)
+ if (driver->attach_adapter)
/* 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);
+ mutex_unlock(&core_lists);
return res;
+
+out_list:
+ list_del(&adap->list);
+ idr_remove(&i2c_adapter_idr, adap->nr);
+ goto out_unlock;
}
+/**
+ * i2c_add_adapter - declare i2c adapter, use dynamic bus number
+ * @adapter: the adapter to add
+ * Context: can sleep
+ *
+ * This routine is used to declare an I2C adapter when its bus number
+ * doesn't matter. Examples: for I2C adapters dynamically added by
+ * USB links or PCI plugin cards.
+ *
+ * When this returns zero, a new bus number was allocated and stored
+ * in adap->nr, and the specified adapter became available for clients.
+ * Otherwise, a negative errno value is returned.
+ */
+int i2c_add_adapter(struct i2c_adapter *adapter)
+{
+ int id, res = 0;
+
+retry:
+ if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0)
+ return -ENOMEM;
+
+ mutex_lock(&core_lists);
+ /* "above" here means "above or equal to", sigh */
+ res = idr_get_new_above(&i2c_adapter_idr, adapter,
+ __i2c_first_dynamic_bus_num, &id);
+ mutex_unlock(&core_lists);
+ if (res < 0) {
+ if (res == -EAGAIN)
+ goto retry;
+ return res;
+ }
+
+ adapter->nr = id;
+ return i2c_register_adapter(adapter);
+}
+EXPORT_SYMBOL(i2c_add_adapter);
+
+/**
+ * i2c_add_numbered_adapter - declare i2c adapter, use static bus number
+ * @adap: the adapter to register (with adap->nr initialized)
+ * Context: can sleep
+ *
+ * This routine is used to declare an I2C adapter when its bus number
+ * matters. Example: for I2C adapters from system-on-chip CPUs, or
+ * otherwise built in to the system's mainboard, and where i2c_board_info
+ * is used to properly configure I2C devices.
+ *
+ * If no devices have pre-been declared for this bus, then be sure to
+ * register the adapter before any dynamically allocated ones. Otherwise
+ * the required bus ID may not be available.
+ *
+ * When this returns zero, the specified adapter became available for
+ * clients using the bus number provided in adap->nr. Also, the table
+ * of I2C devices pre-declared using i2c_register_board_info() is scanned,
+ * and the appropriate driver model device nodes are created. Otherwise, a
+ * negative errno value is returned.
+ */
+int i2c_add_numbered_adapter(struct i2c_adapter *adap)
+{
+ int id;
+ int status;
+
+ if (adap->nr & ~MAX_ID_MASK)
+ return -EINVAL;
+
+retry:
+ if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0)
+ return -ENOMEM;
+
+ mutex_lock(&core_lists);
+ /* "above" here means "above or equal to", sigh;
+ * we need the "equal to" result to force the result
+ */
+ status = idr_get_new_above(&i2c_adapter_idr, adap, adap->nr, &id);
+ if (status == 0 && id != adap->nr) {
+ status = -EBUSY;
+ idr_remove(&i2c_adapter_idr, id);
+ }
+ mutex_unlock(&core_lists);
+ if (status == -EAGAIN)
+ goto retry;
+
+ if (status == 0)
+ status = i2c_register_adapter(adap);
+ return status;
+}
+EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter);
+
+/**
+ * i2c_del_adapter - unregister I2C adapter
+ * @adap: the adapter being unregistered
+ * Context: can sleep
+ *
+ * This unregisters an I2C adapter which was previously registered
+ * by @i2c_add_adapter or @i2c_add_numbered_adapter.
+ */
int i2c_del_adapter(struct i2c_adapter *adap)
{
struct list_head *item, *_n;
struct i2c_client *client;
int res = 0;
- down(&core_lists);
+ mutex_lock(&core_lists);
/* First make sure that this adapter was ever added */
list_for_each_entry(adap_from_list, &adapters, list) {
break;
}
if (adap_from_list != adap) {
- pr_debug("I2C: Attempting to delete an unregistered "
- "adapter\n");
+ pr_debug("i2c-core: attempting to delete unregistered "
+ "adapter [%s]\n", adap->name);
res = -EINVAL;
goto out_unlock;
}
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);
+ dev_err(&adap->dev, "detach_adapter failed "
+ "for driver [%s]\n",
+ driver->driver.name);
goto out_unlock;
}
}
/* detach any active clients. This must be done first, because
- * it can fail; in which case we give upp. */
+ * it can fail; in which case we give up. */
list_for_each_safe(item, _n, &adap->clients) {
+ struct i2c_driver *driver;
+
client = list_entry(item, struct i2c_client, list);
+ driver = client->driver;
+
+ /* new style, follow standard driver model */
+ if (!driver || is_newstyle_driver(driver)) {
+ i2c_unregister_device(client);
+ continue;
+ }
- /* 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. ",
+ /* legacy drivers create and remove clients themselves */
+ if ((res = driver->detach_client(client))) {
+ dev_err(&adap->dev, "detach_client failed for client "
+ "[%s] at address 0x%02x\n", client->name,
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 */
+ /* free bus id */
idr_remove(&i2c_adapter_idr, adap->nr);
- dev_dbg(&adap->dev, "adapter unregistered\n");
+ dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name);
out_unlock:
- up(&core_lists);
+ mutex_unlock(&core_lists);
return res;
}
+EXPORT_SYMBOL(i2c_del_adapter);
-/* -----
- * What follows is the "upwards" interface: commands for talking to clients,
- * which implement the functions to access the physical information of the
- * chips.
+/* ------------------------------------------------------------------------- */
+
+/*
+ * An i2c_driver is used with one or more i2c_client (device) nodes to access
+ * i2c slave chips, on a bus instance associated with some i2c_adapter. There
+ * are two models for binding the driver to its device: "new style" drivers
+ * follow the standard Linux driver model and just respond to probe() calls
+ * issued if the driver core sees they match(); "legacy" drivers create device
+ * nodes themselves.
*/
-int i2c_add_driver(struct i2c_driver *driver)
+int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
{
- struct list_head *item;
- struct i2c_adapter *adapter;
- int res = 0;
-
- down(&core_lists);
+ int res;
+
+ /* new style driver methods can't mix with legacy ones */
+ if (is_newstyle_driver(driver)) {
+ if (driver->attach_adapter || driver->detach_adapter
+ || driver->detach_client) {
+ printk(KERN_WARNING
+ "i2c-core: driver [%s] is confused\n",
+ driver->driver.name);
+ return -EINVAL;
+ }
+ }
/* add the driver to the list of i2c drivers in the driver core */
- driver->driver.name = driver->name;
+ driver->driver.owner = owner;
driver->driver.bus = &i2c_bus_type;
- driver->driver.probe = i2c_device_probe;
- driver->driver.remove = i2c_device_remove;
+ /* for new style drivers, when registration returns the driver core
+ * will have called probe() for all matching-but-unbound devices.
+ */
res = driver_register(&driver->driver);
if (res)
- goto out_unlock;
-
+ return res;
+
+ mutex_lock(&core_lists);
+
list_add_tail(&driver->list,&drivers);
- pr_debug("i2c-core: driver %s registered.\n", driver->name);
+ pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name);
+
+ /* legacy drivers scan i2c busses directly */
+ if (driver->attach_adapter) {
+ struct i2c_adapter *adapter;
- /* 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);
+ list_for_each_entry(adapter, &adapters, list) {
driver->attach_adapter(adapter);
}
}
- out_unlock:
- up(&core_lists);
- return res;
+ mutex_unlock(&core_lists);
+ return 0;
}
+EXPORT_SYMBOL(i2c_register_driver);
-int i2c_del_driver(struct i2c_driver *driver)
+/**
+ * i2c_del_driver - unregister I2C driver
+ * @driver: the driver being unregistered
+ * Context: can sleep
+ */
+void 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);
+ mutex_lock(&core_lists);
+
+ /* new-style driver? */
+ if (is_newstyle_driver(driver))
+ goto unregister;
/* 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
+ * 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;
+ if (driver->detach_adapter(adap)) {
+ dev_err(&adap->dev, "detach_adapter failed "
+ "for driver [%s]\n",
+ driver->driver.name);
}
} 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,
+ dev_dbg(&adap->dev, "detaching client [%s] "
+ "at 0x%02x\n", client->name,
+ client->addr);
+ if (driver->detach_client(client)) {
+ dev_err(&adap->dev, "detach_client "
+ "failed for client [%s] at "
+ "0x%02x\n", client->name,
client->addr);
- goto out_unlock;
}
}
}
}
+ unregister:
driver_unregister(&driver->driver);
list_del(&driver->list);
- pr_debug("i2c-core: driver unregistered: %s\n", driver->name);
+ pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name);
- out_unlock:
- up(&core_lists);
- return 0;
+ mutex_unlock(&core_lists);
}
+EXPORT_SYMBOL(i2c_del_driver);
+
+/* ------------------------------------------------------------------------- */
static int __i2c_check_addr(struct i2c_adapter *adapter, unsigned int addr)
{
{
int rval;
- down(&adapter->clist_lock);
+ mutex_lock(&adapter->clist_lock);
rval = __i2c_check_addr(adapter, addr);
- up(&adapter->clist_lock);
+ mutex_unlock(&adapter->clist_lock);
return rval;
}
+EXPORT_SYMBOL(i2c_check_addr);
int i2c_attach_client(struct i2c_client *client)
{
struct i2c_adapter *adapter = client->adapter;
+ int res = 0;
- down(&adapter->clist_lock);
+ mutex_lock(&adapter->clist_lock);
if (__i2c_check_addr(client->adapter, client->addr)) {
- up(&adapter->clist_lock);
- return -EBUSY;
+ res = -EBUSY;
+ goto out_unlock;
}
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->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;
-
+
+ if (client->driver)
+ client->dev.driver = &client->driver->driver;
+
+ if (client->driver && !is_newstyle_driver(client->driver)) {
+ client->dev.release = i2c_client_release;
+ client->dev.uevent_suppress = 1;
+ } else
+ client->dev.release = i2c_client_dev_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);
-
+ dev_dbg(&adapter->dev, "client [%s] registered with bus id %s\n",
+ client->name, client->dev.bus_id);
+ res = device_register(&client->dev);
+ if (res)
+ goto out_list;
+ mutex_unlock(&adapter->clist_lock);
+
+ if (adapter->client_register) {
+ if (adapter->client_register(client)) {
+ dev_dbg(&adapter->dev, "client_register "
+ "failed for client [%s] at 0x%02x\n",
+ client->name, client->addr);
+ }
+ }
+
return 0;
-}
+out_list:
+ list_del(&client->list);
+ dev_err(&adapter->dev, "Failed to attach i2c client %s at 0x%02x "
+ "(%d)\n", client->name, client->addr, res);
+out_unlock:
+ mutex_unlock(&adapter->clist_lock);
+ return res;
+}
+EXPORT_SYMBOL(i2c_attach_client);
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))
+
+ if (client->usage_count > 0) {
+ dev_warn(&client->dev, "Client [%s] still busy, "
+ "can't detach\n", client->name);
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);
+ "client_unregister [%s] failed, "
+ "client not detached\n", client->name);
goto out;
}
}
- down(&adapter->clist_lock);
+ mutex_lock(&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);
+ mutex_unlock(&adapter->clist_lock);
wait_for_completion(&client->released);
out:
return res;
}
+EXPORT_SYMBOL(i2c_detach_client);
static int i2c_inc_use_client(struct i2c_client *client)
{
- if (!try_module_get(client->driver->owner))
+ if (!try_module_get(client->driver->driver.owner))
return -ENODEV;
if (!try_module_get(client->adapter->owner)) {
- module_put(client->driver->owner);
+ module_put(client->driver->driver.owner);
return -ENODEV;
}
static void i2c_dec_use_client(struct i2c_client *client)
{
- module_put(client->driver->owner);
+ module_put(client->driver->driver.owner);
module_put(client->adapter->owner);
}
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++;
- }
+ client->usage_count++;
return 0;
- busy:
- i2c_dec_use_client(client);
- return -EBUSY;
}
+EXPORT_SYMBOL(i2c_use_client);
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;
- }
+ if (!client->usage_count) {
+ pr_debug("i2c-core: %s used one too many times\n",
+ __FUNCTION__);
+ return -EPERM;
}
-
+
+ client->usage_count--;
i2c_dec_use_client(client);
-
+
return 0;
}
+EXPORT_SYMBOL(i2c_release_client);
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);
+ mutex_lock(&adap->clist_lock);
list_for_each(item,&adap->clients) {
client = list_entry(item, struct i2c_client, list);
- if (!try_module_get(client->driver->owner))
+ if (!try_module_get(client->driver->driver.owner))
continue;
if (NULL != client->driver->command) {
- up(&adap->clist_lock);
+ mutex_unlock(&adap->clist_lock);
client->driver->command(client,cmd,arg);
- down(&adap->clist_lock);
+ mutex_lock(&adap->clist_lock);
}
- module_put(client->driver->owner);
+ module_put(client->driver->driver.owner);
}
- up(&adap->clist_lock);
+ mutex_unlock(&adap->clist_lock);
}
+EXPORT_SYMBOL(i2c_clients_command);
static int __init i2c_init(void)
{
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);
}
#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);
+ "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD)
+ ? 'R' : 'W', msgs[ret].addr, msgs[ret].len,
+ (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : "");
}
#endif
- down(&adap->bus_lock);
+ mutex_lock_nested(&adap->bus_lock, adap->level);
ret = adap->algo->master_xfer(adap,msgs,num);
- up(&adap->bus_lock);
+ mutex_unlock(&adap->bus_lock);
return ret;
} else {
return -ENOSYS;
}
}
+EXPORT_SYMBOL(i2c_transfer);
int i2c_master_send(struct i2c_client *client,const char *buf ,int count)
{
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;
- }
+ msg.addr = client->addr;
+ msg.flags = client->flags & I2C_M_TEN;
+ msg.len = count;
+ msg.buf = (char *)buf;
+
+ ret = i2c_transfer(adap, &msg, 1);
+
+ /* If everything went ok (i.e. 1 msg transmitted), return #bytes
+ transmitted, else error code. */
+ return (ret == 1) ? count : ret;
}
+EXPORT_SYMBOL(i2c_master_send);
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;
- }
-}
+ msg.addr = client->addr;
+ msg.flags = client->flags & I2C_M_TEN;
+ msg.flags |= I2C_M_RD;
+ msg.len = count;
+ msg.buf = buf;
+
+ ret = i2c_transfer(adap, &msg, 1);
+
+ /* If everything went ok (i.e. 1 msg transmitted), return #bytes
+ transmitted, else error code. */
+ return (ret == 1) ? count : ret;
+}
+EXPORT_SYMBOL(i2c_master_recv);
int i2c_control(struct i2c_client *client,
unsigned int cmd, unsigned long arg)
}
return ret;
}
+EXPORT_SYMBOL(i2c_control);
/* ----------------------------------------------------
* the i2c address scanning function
* Will not work for 10-bit addresses!
* ----------------------------------------------------
*/
+static int i2c_probe_address(struct i2c_adapter *adapter, int addr, int kind,
+ int (*found_proc) (struct i2c_adapter *, int, int))
+{
+ int err;
+
+ /* Make sure the address is valid */
+ if (addr < 0x03 || addr > 0x77) {
+ dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n",
+ addr);
+ return -EINVAL;
+ }
+
+ /* Skip if already in use */
+ if (i2c_check_addr(adapter, addr))
+ return 0;
+
+ /* Make sure there is something at this address, unless forced */
+ if (kind < 0) {
+ if (i2c_smbus_xfer(adapter, addr, 0, 0, 0,
+ I2C_SMBUS_QUICK, NULL) < 0)
+ return 0;
+
+ /* prevent 24RF08 corruption */
+ if ((addr & ~0x0f) == 0x50)
+ i2c_smbus_xfer(adapter, addr, 0, 0, 0,
+ I2C_SMBUS_QUICK, NULL);
+ }
+
+ /* Finally call the custom detection function */
+ err = found_proc(adapter, addr, kind);
+ /* -ENODEV can be returned if there is a chip at the given address
+ but it isn't supported by this chip driver. We catch it here as
+ this isn't an error. */
+ if (err == -ENODEV)
+ err = 0;
+
+ if (err)
+ dev_warn(&adapter->dev, "Client creation failed at 0x%x (%d)\n",
+ addr, err);
+ return err;
+}
+
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 i, 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;
+ /* Force entries are done first, and are not affected by ignore
+ entries */
+ if (address_data->forces) {
+ unsigned short **forces = address_data->forces;
+ int kind;
+
+ for (kind = 0; forces[kind]; kind++) {
+ for (i = 0; forces[kind][i] != I2C_CLIENT_END;
+ i += 2) {
+ if (forces[kind][i] == adap_id
+ || forces[kind][i] == ANY_I2C_BUS) {
+ dev_dbg(&adapter->dev, "found force "
+ "parameter for adapter %d, "
+ "addr 0x%02x, kind %d\n",
+ adap_id, forces[kind][i + 1],
+ kind);
+ err = i2c_probe_address(adapter,
+ forces[kind][i + 1],
+ kind, found_proc);
+ if (err)
+ return err;
+ }
+ }
+ }
+ }
- for (addr = 0x00; addr <= 0x7f; addr++) {
+ /* Stop here if we can't use SMBUS_QUICK */
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_QUICK)) {
+ if (address_data->probe[0] == I2C_CLIENT_END
+ && address_data->normal_i2c[0] == I2C_CLIENT_END)
+ return 0;
- /* Skip if already in use */
- if (i2c_check_addr(adapter,addr))
- continue;
+ dev_warn(&adapter->dev, "SMBus Quick command not supported, "
+ "can't probe for chips\n");
+ return -1;
+ }
- /* 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;
- }
+ /* Probe entries are done second, and are not affected by ignore
+ entries either */
+ for (i = 0; address_data->probe[i] != I2C_CLIENT_END; i += 2) {
+ if (address_data->probe[i] == adap_id
+ || address_data->probe[i] == ANY_I2C_BUS) {
+ dev_dbg(&adapter->dev, "found probe parameter for "
+ "adapter %d, addr 0x%02x\n", adap_id,
+ address_data->probe[i + 1]);
+ err = i2c_probe_address(adapter,
+ address_data->probe[i + 1],
+ -1, found_proc);
+ if (err)
+ return err;
}
- 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;
+ /* Normal entries are done last, unless shadowed by an ignore entry */
+ for (i = 0; address_data->normal_i2c[i] != I2C_CLIENT_END; i += 1) {
+ int j, ignore;
+
+ ignore = 0;
+ for (j = 0; address_data->ignore[j] != I2C_CLIENT_END;
+ j += 2) {
+ if ((address_data->ignore[j] == adap_id ||
+ address_data->ignore[j] == ANY_I2C_BUS)
+ && address_data->ignore[j + 1]
+ == address_data->normal_i2c[i]) {
+ dev_dbg(&adapter->dev, "found ignore "
+ "parameter for adapter %d, "
+ "addr 0x%02x\n", adap_id,
+ address_data->ignore[j + 1]);
+ ignore = 1;
+ break;
}
}
- if (found)
+ if (ignore)
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);
- }
- }
+ dev_dbg(&adapter->dev, "found normal entry for adapter %d, "
+ "addr 0x%02x\n", adap_id,
+ address_data->normal_i2c[i]);
+ err = i2c_probe_address(adapter, address_data->normal_i2c[i],
+ -1, found_proc);
+ if (err)
+ return err;
+ }
- 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);
- }
+ return 0;
+}
+EXPORT_SYMBOL(i2c_probe);
+
+struct i2c_client *
+i2c_new_probed_device(struct i2c_adapter *adap,
+ struct i2c_board_info *info,
+ unsigned short const *addr_list)
+{
+ int i;
+
+ /* Stop here if the bus doesn't support probing */
+ if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) {
+ dev_err(&adap->dev, "Probing not supported\n");
+ return NULL;
+ }
+
+ mutex_lock(&adap->clist_lock);
+ for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) {
+ /* Check address validity */
+ if (addr_list[i] < 0x03 || addr_list[i] > 0x77) {
+ dev_warn(&adap->dev, "Invalid 7-bit address "
+ "0x%02x\n", addr_list[i]);
+ continue;
}
- 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);
- }
+ /* Check address availability */
+ if (__i2c_check_addr(adap, addr_list[i])) {
+ dev_dbg(&adap->dev, "Address 0x%02x already in "
+ "use, not probing\n", addr_list[i]);
+ continue;
}
- 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);
- }
+
+ /* Test address responsiveness
+ The default probe method is a quick write, but it is known
+ to corrupt the 24RF08 EEPROMs due to a state machine bug,
+ and could also irreversibly write-protect some EEPROMs, so
+ for address ranges 0x30-0x37 and 0x50-0x5f, we use a byte
+ read instead. Also, some bus drivers don't implement
+ quick write, so we fallback to a byte read it that case
+ too. */
+ if ((addr_list[i] & ~0x07) == 0x30
+ || (addr_list[i] & ~0x0f) == 0x50
+ || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) {
+ if (i2c_smbus_xfer(adap, addr_list[i], 0,
+ I2C_SMBUS_READ, 0,
+ I2C_SMBUS_BYTE, NULL) >= 0)
+ break;
+ } else {
+ if (i2c_smbus_xfer(adap, addr_list[i], 0,
+ I2C_SMBUS_WRITE, 0,
+ I2C_SMBUS_QUICK, NULL) >= 0)
+ break;
}
- if (!found)
- continue;
+ }
+ mutex_unlock(&adap->clist_lock);
- /* 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;
+ if (addr_list[i] == I2C_CLIENT_END) {
+ dev_dbg(&adap->dev, "Probing failed, no device found\n");
+ return NULL;
}
- return 0;
-}
-/*
- * return id number for a specific adapter
- */
-int i2c_adapter_id(struct i2c_adapter *adap)
-{
- return adap->nr;
+ info->addr = addr_list[i];
+ return i2c_new_device(adap, info);
}
+EXPORT_SYMBOL_GPL(i2c_new_probed_device);
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;
+
+ mutex_lock(&core_lists);
+ adapter = (struct i2c_adapter *)idr_find(&i2c_adapter_idr, id);
+ if (adapter && !try_module_get(adapter->owner))
+ adapter = NULL;
+
+ mutex_unlock(&core_lists);
+ return adapter;
}
+EXPORT_SYMBOL(i2c_get_adapter);
void i2c_put_adapter(struct i2c_adapter *adap)
{
module_put(adap->owner);
}
+EXPORT_SYMBOL(i2c_put_adapter);
/* The SMBus parts */
-#define POLY (0x1070U << 3)
+#define POLY (0x1070U << 3)
static u8
crc8(u16 data)
{
int i;
-
+
for(i = 0; i < 8; i++) {
- if (data & 0x8000)
+ 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)
+/* Incremental CRC8 over count bytes in the array pointed to by p */
+static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count)
{
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);
+ crc = crc8((crc ^ p[i]) << 8);
return crc;
}
-static u8 i2c_smbus_pec(int count, u8 *first, u8 *rest)
+/* Assume a 7-bit address, which is reasonable for SMBus */
+static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg)
{
- return i2c_smbus_partial_pec(0, count, first, rest);
+ /* The address will be sent first */
+ u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD);
+ pec = i2c_smbus_pec(pec, &addr, 1);
+
+ /* The data buffer follows */
+ return i2c_smbus_pec(pec, msg->buf, msg->len);
}
-/* 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)
+/* Used for write only transactions */
+static inline void i2c_smbus_add_pec(struct i2c_msg *msg)
{
- 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;
+ msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg);
+ msg->len++;
}
-static int i2c_smbus_check_pec(u16 addr, u8 command, int size, u8 partial,
- union i2c_smbus_data *data)
+/* Return <0 on CRC error
+ If there was a write before this read (most cases) we need to take the
+ partial CRC from the write part into account.
+ Note that this function does modify the message (we need to decrease the
+ message length to hide the CRC byte from the caller). */
+static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg)
{
- u8 buf[3], rpec, cpec;
+ u8 rpec = msg->buf[--msg->len];
+ cpec = i2c_smbus_msg_pec(cpec, msg);
- 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;
+ 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);
+ value,0,I2C_SMBUS_QUICK,NULL);
}
+EXPORT_SYMBOL(i2c_smbus_write_quick);
s32 i2c_smbus_read_byte(struct i2c_client *client)
{
I2C_SMBUS_READ,0,I2C_SMBUS_BYTE, &data))
return -1;
else
- return 0x0FF & data.byte;
+ return data.byte;
}
+EXPORT_SYMBOL(i2c_smbus_read_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);
+ I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL);
}
+EXPORT_SYMBOL(i2c_smbus_write_byte);
s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command)
{
I2C_SMBUS_READ,command, I2C_SMBUS_BYTE_DATA,&data))
return -1;
else
- return 0x0FF & data.byte;
+ return data.byte;
}
+EXPORT_SYMBOL(i2c_smbus_read_byte_data);
s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value)
{
I2C_SMBUS_WRITE,command,
I2C_SMBUS_BYTE_DATA,&data);
}
+EXPORT_SYMBOL(i2c_smbus_write_byte_data);
s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command)
{
I2C_SMBUS_READ,command, I2C_SMBUS_WORD_DATA, &data))
return -1;
else
- return 0x0FFFF & data.word;
+ return data.word;
}
+EXPORT_SYMBOL(i2c_smbus_read_word_data);
s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value)
{
I2C_SMBUS_WRITE,command,
I2C_SMBUS_WORD_DATA,&data);
}
+EXPORT_SYMBOL(i2c_smbus_write_word_data);
+
+/* Returns the number of read bytes */
+s32 i2c_smbus_read_block_data(struct i2c_client *client, u8 command,
+ u8 *values)
+{
+ union i2c_smbus_data data;
+
+ if (i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+ I2C_SMBUS_READ, command,
+ I2C_SMBUS_BLOCK_DATA, &data))
+ return -1;
+
+ memcpy(values, &data.block[1], data.block[0]);
+ return data.block[0];
+}
+EXPORT_SYMBOL(i2c_smbus_read_block_data);
s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command,
- u8 length, u8 *values)
+ u8 length, const 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;
+ memcpy(&data.block[1], values, length);
return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
I2C_SMBUS_WRITE,command,
I2C_SMBUS_BLOCK_DATA,&data);
}
+EXPORT_SYMBOL(i2c_smbus_write_block_data);
/* Returns the number of read bytes */
-s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, u8 *values)
+s32 i2c_smbus_read_i2c_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;
+ data.block[0] = length;
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];
- }
+
+ memcpy(values, &data.block[1], data.block[0]);
+ return data.block[0];
+}
+EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data);
+
+s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command,
+ u8 length, const u8 *values)
+{
+ union i2c_smbus_data data;
+
+ if (length > I2C_SMBUS_BLOCK_MAX)
+ length = I2C_SMBUS_BLOCK_MAX;
+ data.block[0] = length;
+ memcpy(data.block + 1, values, length);
+ return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+ I2C_SMBUS_WRITE, command,
+ I2C_SMBUS_I2C_BLOCK_DATA, &data);
}
+EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data);
-/* Simulate a SMBus command using the i2c protocol
+/* 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,
+static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
unsigned short flags,
- char read_write, u8 command, int size,
+ 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];
+ unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3];
+ unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2];
int num = read_write == I2C_SMBUS_READ?2:1;
- struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 },
+ struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 },
{ addr, flags | I2C_M_RD, 0, msgbuf1 }
};
int i;
+ u8 partial_pec = 0;
msgbuf0[0] = command;
switch(size) {
else {
msg[0].len=3;
msgbuf0[1] = data->word & 0xff;
- msgbuf0[2] = (data->word >> 8) & 0xff;
+ msgbuf0[2] = data->word >> 8;
}
break;
case I2C_SMBUS_PROC_CALL:
msg[0].len = 3;
msg[1].len = 2;
msgbuf0[1] = data->word & 0xff;
- msgbuf0[2] = (data->word >> 8) & 0xff;
+ msgbuf0[2] = data->word >> 8;
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;
+ msg[1].flags |= I2C_M_RECV_LEN;
+ msg[1].len = 1; /* block length will be added by
+ the underlying bus driver */
} else {
msg[0].len = data->block[0] + 2;
if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) {
data->block[0]);
return -1;
}
- if(size == I2C_SMBUS_BLOCK_DATA_PEC)
- (msg[0].len)++;
- for (i = 1; i <= msg[0].len; i++)
+ 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;
+ num = 2; /* Another special case */
+ read_write = I2C_SMBUS_READ;
+ if (data->block[0] > I2C_SMBUS_BLOCK_MAX) {
+ dev_err(&adapter->dev, "%s called with invalid "
+ "block proc call size (%d)\n", __FUNCTION__,
+ data->block[0]);
+ return -1;
+ }
+ msg[0].len = data->block[0] + 2;
+ for (i = 1; i < msg[0].len; i++)
+ msgbuf0[i] = data->block[i-1];
+ msg[1].flags |= I2C_M_RECV_LEN;
+ msg[1].len = 1; /* block length will be added by
+ the underlying bus driver */
+ break;
case I2C_SMBUS_I2C_BLOCK_DATA:
if (read_write == I2C_SMBUS_READ) {
- msg[1].len = I2C_SMBUS_I2C_BLOCK_MAX;
+ msg[1].len = data->block[0];
} else {
msg[0].len = data->block[0] + 1;
- if (msg[0].len > I2C_SMBUS_I2C_BLOCK_MAX + 1) {
+ if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) {
dev_err(&adapter->dev, "i2c_smbus_xfer_emulated called with "
"invalid block write size (%d)\n",
data->block[0]);
return -1;
}
+ i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK
+ && size != I2C_SMBUS_I2C_BLOCK_DATA);
+ if (i) {
+ /* Compute PEC if first message is a write */
+ if (!(msg[0].flags & I2C_M_RD)) {
+ if (num == 1) /* Write only */
+ i2c_smbus_add_pec(&msg[0]);
+ else /* Write followed by read */
+ partial_pec = i2c_smbus_msg_pec(0, &msg[0]);
+ }
+ /* Ask for PEC if last message is a read */
+ if (msg[num-1].flags & I2C_M_RD)
+ msg[num-1].len++;
+ }
+
if (i2c_transfer(adapter, msg, num) < 0)
return -1;
+ /* Check PEC if last message is a read */
+ if (i && (msg[num-1].flags & I2C_M_RD)) {
+ if (i2c_smbus_check_pec(partial_pec, &msg[num-1]) < 0)
+ return -1;
+ }
+
if (read_write == I2C_SMBUS_READ)
switch(size) {
case I2C_SMBUS_BYTE:
case I2C_SMBUS_BYTE_DATA:
data->byte = msgbuf1[0];
break;
- case I2C_SMBUS_WORD_DATA:
+ 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++)
+ for (i = 0; i < data->block[0]; i++)
data->block[i+1] = msgbuf1[i];
break;
+ case I2C_SMBUS_BLOCK_DATA:
+ case I2C_SMBUS_BLOCK_PROC_CALL:
+ for (i = 0; i < msgbuf1[0] + 1; i++)
+ data->block[i] = 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,
+ 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);
+ mutex_lock(&adapter->bus_lock);
res = adapter->algo->smbus_xfer(adapter,addr,flags,read_write,
command,size,data);
- up(&adapter->bus_lock);
+ mutex_unlock(&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");
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff