Revert "i2c: Replace list-based mechanism for handling userspace-created clients"

This reverts commit 3cfe39b3a845593a485ab1c716615979004ef9f6. Mux
handling is not sufficiently implemented. It needs more time.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index c31fd1dba3bd..4955d9e76c5f 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -313,6 +313,8 @@ 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
@@ -333,7 +335,6 @@ struct i2c_client {
 #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 +346,7 @@ 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 +753,9 @@ 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;