niansa-misc/linux
1
0
Fork 0
mirror of synced 2025-03-06 20:59:54 +01:00
Code Issues Projects Releases Packages Wiki Activity

i2c-for-6.14-rc2

Browse source 
It turned out the new mechanism for handling created devices does not
 handle all muxing cases. Revert the changes to give a proper solution
 more time.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmenRrUACgkQFA3kzBSg
 KbaK9w//aKeNus/4PEaYikf6XoVbi8SVYMgyX/mNBhcI21koqbVjc8Mi4DTsW9VD
 p7RpSGH9QPGTMtpqoSXVjBUKf9kK4FfyDb0EJMcXWUvewBWOmcPrRmKrRsNFfEJL
 sLy37lVzOBJdUc+TipdUG2oOtMirt6SlsJt9DNZy64b9r2wB/2egjhQ8VXo1exDI
 o4pU9lboycDwp4xQ1g9CjoHKOWQmQS7ZBvLz49XzA/wC0G0JBAlmzqr83Ke1oRYM
 wLOzZH9JWGgw7tLJE0fmAQfOTCt6r3uxNmB1/h1xbHmyjFY1qHofVdZC7mXr20cs
 /Zku5wjA/8iFF6j6CiQDpZyPQJJJHxq7LQyFbYP0419GNxkZjb4KML8dZvEYuMaj
 A2DqhegQ5frqGzk+JvX6kysT/sKhZ/pW2E00X3wmHLDpu4h0/TWiloMSIDZ37LR5
 vuh8VKtK4zDLrJAi1WPXzwTvoGziT1HCcEXmoFVaTb5Us0w6Cc+5sAryYCnVYmN9
 ku2Z22bk2/e60HzZ0FjX9HOuIIcIIbjMNsUtTrykHUCRNxU960AjPxy5IBXjilk2
 v5IpYi/3ZbZEtC3ozfrwzYp4g1P4leclDndMa0fz+9IDZK6HoRmUSrB2OIMQDsC4
 aN1sK56n+oCjj8IJ3mRUYeQvMQTdncAG4g41Mx++jKePpcWYvXM=
 =uhz5
 -----END PGP SIGNATURE-----

Merge tag 'i2c-for-6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c reverts from Wolfram Sang:
 "It turned out the new mechanism for handling created devices does not
  handle all muxing cases.

  Revert the changes to give a proper solution more time"

* tag 'i2c-for-6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  Revert "i2c: Replace list-based mechanism for handling auto-detected clients"
  Revert "i2c: Replace list-based mechanism for handling userspace-created clients"
This commit is contained in:
Linus Torvalds 2025-02-08 13:35:17 -08:00
commit 74b5161d57
2 changed files with 84 additions and 41 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

115
drivers/i2c/i2c-core-base.c
View file

@ -1300,12 +1300,14 @@ new_device_store(struct device *dev, struct device_attribute *attr,
info.flags |= I2C_CLIENT_SLAVE;
}
info.flags |= I2C_CLIENT_USER;
client = i2c_new_client_device(adap, &info);
if (IS_ERR(client))
return PTR_ERR(client);
/* Keep track of the added device */
mutex_lock(&adap->userspace_clients_lock);
list_add_tail(&client->detected, &adap->userspace_clients);
mutex_unlock(&adap->userspace_clients_lock);
dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device",
info.type, info.addr);
@ -1313,15 +1315,6 @@ new_device_store(struct device *dev, struct device_attribute *attr,
}
static DEVICE_ATTR_WO(new_device);
static int __i2c_find_user_addr(struct device *dev, const void *addrp)
{
struct i2c_client *client = i2c_verify_client(dev);
unsigned short addr = *(unsigned short *)addrp;
return client && client->flags & I2C_CLIENT_USER &&
i2c_encode_flags_to_addr(client) == addr;
}
/*
* And of course let the users delete the devices they instantiated, if
* they got it wrong. This interface can only be used to delete devices
@ -1336,7 +1329,7 @@ delete_device_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_adapter *adap = to_i2c_adapter(dev);
struct device *child_dev;
struct i2c_client *client, *next;
unsigned short addr;
char end;
int res;
@ -1352,19 +1345,28 @@ delete_device_store(struct device *dev, struct device_attribute *attr,
return -EINVAL;
}
mutex_lock(&core_lock);
/* Make sure the device was added through sysfs */
child_dev = device_find_child(&adap->dev, &addr, __i2c_find_user_addr);
if (child_dev) {
i2c_unregister_device(i2c_verify_client(child_dev));
put_device(child_dev);
} else {
dev_err(dev, "Can't find userspace-created device at %#x\n", addr);
count = -ENOENT;
}
mutex_unlock(&core_lock);
res = -ENOENT;
mutex_lock_nested(&adap->userspace_clients_lock,
i2c_adapter_depth(adap));
list_for_each_entry_safe(client, next, &adap->userspace_clients,
detected) {
if (i2c_encode_flags_to_addr(client) == addr) {
dev_info(dev, "%s: Deleting device %s at 0x%02hx\n",
"delete_device", client->name, client->addr);
return count;
list_del(&client->detected);
i2c_unregister_device(client);
res = count;
break;
}
}
mutex_unlock(&adap->userspace_clients_lock);
if (res < 0)
dev_err(dev, "%s: Can't find device in list\n",
"delete_device");
return res;
}
static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL,
delete_device_store);
@ -1535,6 +1537,8 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
adap->locked_flags = 0;
rt_mutex_init(&adap->bus_lock);
rt_mutex_init(&adap->mux_lock);
mutex_init(&adap->userspace_clients_lock);
INIT_LIST_HEAD(&adap->userspace_clients);
/* Set default timeout to 1 second if not already set */
if (adap->timeout == 0)
@ -1700,6 +1704,23 @@ int i2c_add_numbered_adapter(struct i2c_adapter *adap)
}
EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter);
static void i2c_do_del_adapter(struct i2c_driver *driver,
struct i2c_adapter *adapter)
{
struct i2c_client *client, *_n;
/* Remove the devices we created ourselves as the result of hardware
* probing (using a driver's detect method) */
list_for_each_entry_safe(client, _n, &driver->clients, detected) {
if (client->adapter == adapter) {
dev_dbg(&adapter->dev, "Removing %s at 0x%x\n",
client->name, client->addr);
list_del(&client->detected);
i2c_unregister_device(client);
}
}
}
static int __unregister_client(struct device *dev, void *dummy)
{
struct i2c_client *client = i2c_verify_client(dev);
@ -1715,6 +1736,12 @@ static int __unregister_dummy(struct device *dev, void *dummy)
return 0;
}
static int __process_removed_adapter(struct device_driver *d, void *data)
{
i2c_do_del_adapter(to_i2c_driver(d), data);
return 0;
}
/**
* i2c_del_adapter - unregister I2C adapter
* @adap: the adapter being unregistered
@ -1726,6 +1753,7 @@ static int __unregister_dummy(struct device *dev, void *dummy)
void i2c_del_adapter(struct i2c_adapter *adap)
{
struct i2c_adapter *found;
struct i2c_client *client, *next;
/* First make sure that this adapter was ever added */
mutex_lock(&core_lock);
@ -1737,16 +1765,31 @@ void i2c_del_adapter(struct i2c_adapter *adap)
}
i2c_acpi_remove_space_handler(adap);
/* Tell drivers about this removal */
mutex_lock(&core_lock);
bus_for_each_drv(&i2c_bus_type, NULL, adap,
__process_removed_adapter);
mutex_unlock(&core_lock);
/* Remove devices instantiated from sysfs */
mutex_lock_nested(&adap->userspace_clients_lock,
i2c_adapter_depth(adap));
list_for_each_entry_safe(client, next, &adap->userspace_clients,
detected) {
dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name,
client->addr);
list_del(&client->detected);
i2c_unregister_device(client);
}
mutex_unlock(&adap->userspace_clients_lock);
/* Detach any active clients. This can't fail, thus we do not
* check the returned value. This is a two-pass process, because
* we can't remove the dummy devices during the first pass: they
* could have been instantiated by real devices wishing to clean
* them up properly, so we give them a chance to do that first. */
mutex_lock(&core_lock);
device_for_each_child(&adap->dev, NULL, __unregister_client);
device_for_each_child(&adap->dev, NULL, __unregister_dummy);
mutex_unlock(&core_lock);
/* device name is gone after device_unregister */
dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name);
@ -1966,6 +2009,7 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
/* add the driver to the list of i2c drivers in the driver core */
driver->driver.owner = owner;
driver->driver.bus = &i2c_bus_type;
INIT_LIST_HEAD(&driver->clients);
/* When registration returns, the driver core
* will have called probe() for all matching-but-unbound devices.
@ -1983,13 +2027,10 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
}
EXPORT_SYMBOL(i2c_register_driver);
static int __i2c_unregister_detected_client(struct device *dev, void *argp)
static int __process_removed_driver(struct device *dev, void *data)
{
struct i2c_client *client = i2c_verify_client(dev);
if (client && client->flags & I2C_CLIENT_AUTO)
i2c_unregister_device(client);
if (dev->type == &i2c_adapter_type)
i2c_do_del_adapter(data, to_i2c_adapter(dev));
return 0;
}
@ -2000,12 +2041,7 @@ static int __i2c_unregister_detected_client(struct device *dev, void *argp)
*/
void i2c_del_driver(struct i2c_driver *driver)
{
mutex_lock(&core_lock);
/* Satisfy __must_check, function can't fail */
if (driver_for_each_device(&driver->driver, NULL, NULL,
__i2c_unregister_detected_client)) {
}
mutex_unlock(&core_lock);
i2c_for_each_dev(driver, __process_removed_driver);
driver_unregister(&driver->driver);
pr_debug("driver [%s] unregistered\n", driver->driver.name);
@ -2432,7 +2468,6 @@ static int i2c_detect_address(struct i2c_client *temp_client,
/* Finally call the custom detection function */
memset(&info, 0, sizeof(struct i2c_board_info));
info.addr = addr;
info.flags = I2C_CLIENT_AUTO;
err = driver->detect(temp_client, &info);
if (err) {
/* -ENODEV is returned if the detection fails. We catch it
@ -2459,7 +2494,9 @@ static int i2c_detect_address(struct i2c_client *temp_client,
dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n",
info.type, info.addr);
client = i2c_new_client_device(adapter, &info);
if (IS_ERR(client))
if (!IS_ERR(client))
list_add_tail(&client->detected, &driver->clients);
else
dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n",
info.type, info.addr);
}

10
include/linux/i2c.h
View file

@ -244,6 +244,7 @@ enum i2c_driver_flags {
* @id_table: List of I2C devices supported by this driver
* @detect: Callback for device detection
* @address_list: The I2C addresses to probe (for detect)
* @clients: List of detected clients we created (for i2c-core use only)
* @flags: A bitmask of flags defined in &enum i2c_driver_flags
*
* The driver.owner field should be set to the module owner of this driver.
@ -298,6 +299,7 @@ struct i2c_driver {
/* Device detection callback for automatic device creation */
int (*detect)(struct i2c_client *client, struct i2c_board_info *info);
const unsigned short *address_list;
struct list_head clients;
u32 flags;
};
@ -313,6 +315,8 @@ struct i2c_driver {
* @dev: Driver model device node for the slave.
* @init_irq: IRQ that was set at initialization
* @irq: indicates the IRQ generated by this device (if any)
* @detected: member of an i2c_driver.clients list or i2c-core's
* userspace_devices list
* @slave_cb: Callback when I2C slave mode of an adapter is used. The adapter
* calls it to pass on slave events to the slave driver.
* @devres_group_id: id of the devres group that will be created for resources
@ -332,8 +336,6 @@ struct i2c_client {
#define I2C_CLIENT_SLAVE 0x20 /* we are the slave */
#define I2C_CLIENT_HOST_NOTIFY 0x40 /* We want to use I2C host notify */
#define I2C_CLIENT_WAKE 0x80 /* for board_info; true iff can wake */
#define I2C_CLIENT_AUTO 0x100 /* client was auto-detected */
#define I2C_CLIENT_USER 0x200 /* client was userspace-created */
#define I2C_CLIENT_SCCB 0x9000 /* Use Omnivision SCCB protocol */
/* Must match I2C_M_STOP|IGNORE_NAK */
@ -345,6 +347,7 @@ struct i2c_client {
struct device dev; /* the device structure */
int init_irq; /* irq set at initialization */
int irq; /* irq issued by device */
struct list_head detected;
#if IS_ENABLED(CONFIG_I2C_SLAVE)
i2c_slave_cb_t slave_cb; /* callback for slave mode */
#endif
@ -751,6 +754,9 @@ struct i2c_adapter {
char name[48];
struct completion dev_released;
struct mutex userspace_clients_lock;
struct list_head userspace_clients;
struct i2c_bus_recovery_info *bus_recovery_info;
const struct i2c_adapter_quirks *quirks;