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-rw-r--r--include/linux/i2c.h48
1 files changed, 38 insertions, 10 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index fb9af6a0fe9c..08be0d21864c 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -35,6 +35,8 @@
35#include <linux/sched.h> /* for completion */ 35#include <linux/sched.h> /* for completion */
36#include <linux/mutex.h> 36#include <linux/mutex.h>
37 37
38extern struct bus_type i2c_bus_type;
39
38/* --- General options ------------------------------------------------ */ 40/* --- General options ------------------------------------------------ */
39 41
40struct i2c_msg; 42struct i2c_msg;
@@ -43,6 +45,7 @@ struct i2c_adapter;
43struct i2c_client; 45struct i2c_client;
44struct i2c_driver; 46struct i2c_driver;
45union i2c_smbus_data; 47union i2c_smbus_data;
48struct i2c_board_info;
46 49
47/* 50/*
48 * The master routines are the ones normally used to transmit data to devices 51 * The master routines are the ones normally used to transmit data to devices
@@ -69,9 +72,8 @@ extern s32 i2c_smbus_xfer (struct i2c_adapter * adapter, u16 addr,
69 union i2c_smbus_data * data); 72 union i2c_smbus_data * data);
70 73
71/* Now follow the 'nice' access routines. These also document the calling 74/* Now follow the 'nice' access routines. These also document the calling
72 conventions of smbus_access. */ 75 conventions of i2c_smbus_xfer. */
73 76
74extern s32 i2c_smbus_write_quick(struct i2c_client * client, u8 value);
75extern s32 i2c_smbus_read_byte(struct i2c_client * client); 77extern s32 i2c_smbus_read_byte(struct i2c_client * client);
76extern s32 i2c_smbus_write_byte(struct i2c_client * client, u8 value); 78extern s32 i2c_smbus_write_byte(struct i2c_client * client, u8 value);
77extern s32 i2c_smbus_read_byte_data(struct i2c_client * client, u8 command); 79extern s32 i2c_smbus_read_byte_data(struct i2c_client * client, u8 command);
@@ -93,15 +95,33 @@ extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
93 u8 command, u8 length, 95 u8 command, u8 length,
94 const u8 *values); 96 const u8 *values);
95 97
96/* 98/**
97 * A driver is capable of handling one or more physical devices present on 99 * struct i2c_driver - represent an I2C device driver
98 * I2C adapters. This information is used to inform the driver of adapter 100 * @class: What kind of i2c device we instantiate (for detect)
99 * events. 101 * @detect: Callback for device detection
102 * @address_data: The I2C addresses to probe, ignore or force (for detect)
103 * @clients: List of detected clients we created (for i2c-core use only)
100 * 104 *
101 * The driver.owner field should be set to the module owner of this driver. 105 * The driver.owner field should be set to the module owner of this driver.
102 * The driver.name field should be set to the name of this driver. 106 * The driver.name field should be set to the name of this driver.
107 *
108 * For automatic device detection, both @detect and @address_data must
109 * be defined. @class should also be set, otherwise only devices forced
110 * with module parameters will be created. The detect function must
111 * fill at least the name field of the i2c_board_info structure it is
112 * handed upon successful detection, and possibly also the flags field.
113 *
114 * If @detect is missing, the driver will still work fine for enumerated
115 * devices. Detected devices simply won't be supported. This is expected
116 * for the many I2C/SMBus devices which can't be detected reliably, and
117 * the ones which can always be enumerated in practice.
118 *
119 * The i2c_client structure which is handed to the @detect callback is
120 * not a real i2c_client. It is initialized just enough so that you can
121 * call i2c_smbus_read_byte_data and friends on it. Don't do anything
122 * else with it. In particular, calling dev_dbg and friends on it is
123 * not allowed.
103 */ 124 */
104
105struct i2c_driver { 125struct i2c_driver {
106 int id; 126 int id;
107 unsigned int class; 127 unsigned int class;
@@ -141,6 +161,11 @@ struct i2c_driver {
141 161
142 struct device_driver driver; 162 struct device_driver driver;
143 const struct i2c_device_id *id_table; 163 const struct i2c_device_id *id_table;
164
165 /* Device detection callback for automatic device creation */
166 int (*detect)(struct i2c_client *, int kind, struct i2c_board_info *);
167 const struct i2c_client_address_data *address_data;
168 struct list_head clients;
144}; 169};
145#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) 170#define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
146 171
@@ -156,6 +181,7 @@ struct i2c_driver {
156 * @dev: Driver model device node for the slave. 181 * @dev: Driver model device node for the slave.
157 * @irq: indicates the IRQ generated by this device (if any) 182 * @irq: indicates the IRQ generated by this device (if any)
158 * @list: list of active/busy clients (DEPRECATED) 183 * @list: list of active/busy clients (DEPRECATED)
184 * @detected: member of an i2c_driver.clients list
159 * @released: used to synchronize client releases & detaches and references 185 * @released: used to synchronize client releases & detaches and references
160 * 186 *
161 * An i2c_client identifies a single device (i.e. chip) connected to an 187 * An i2c_client identifies a single device (i.e. chip) connected to an
@@ -171,8 +197,9 @@ struct i2c_client {
171 struct i2c_adapter *adapter; /* the adapter we sit on */ 197 struct i2c_adapter *adapter; /* the adapter we sit on */
172 struct i2c_driver *driver; /* and our access routines */ 198 struct i2c_driver *driver; /* and our access routines */
173 struct device dev; /* the device structure */ 199 struct device dev; /* the device structure */
174 int irq; /* irq issued by device (or -1) */ 200 int irq; /* irq issued by device */
175 struct list_head list; /* DEPRECATED */ 201 struct list_head list; /* DEPRECATED */
202 struct list_head detected;
176 struct completion released; 203 struct completion released;
177}; 204};
178#define to_i2c_client(d) container_of(d, struct i2c_client, dev) 205#define to_i2c_client(d) container_of(d, struct i2c_client, dev)
@@ -350,10 +377,11 @@ static inline void i2c_set_adapdata (struct i2c_adapter *dev, void *data)
350#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */ 377#define I2C_CLASS_HWMON (1<<0) /* lm_sensors, ... */
351#define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */ 378#define I2C_CLASS_TV_ANALOG (1<<1) /* bttv + friends */
352#define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */ 379#define I2C_CLASS_TV_DIGITAL (1<<2) /* dvb cards */
353#define I2C_CLASS_DDC (1<<3) /* i2c-matroxfb ? */ 380#define I2C_CLASS_DDC (1<<3) /* DDC bus on graphics adapters */
354#define I2C_CLASS_CAM_ANALOG (1<<4) /* camera with analog CCD */ 381#define I2C_CLASS_CAM_ANALOG (1<<4) /* camera with analog CCD */
355#define I2C_CLASS_CAM_DIGITAL (1<<5) /* most webcams */ 382#define I2C_CLASS_CAM_DIGITAL (1<<5) /* most webcams */
356#define I2C_CLASS_SOUND (1<<6) /* sound devices */ 383#define I2C_CLASS_SOUND (1<<6) /* sound devices */
384#define I2C_CLASS_SPD (1<<7) /* SPD EEPROMs and similar */
357#define I2C_CLASS_ALL (UINT_MAX) /* all of the above */ 385#define I2C_CLASS_ALL (UINT_MAX) /* all of the above */
358 386
359/* i2c_client_address_data is the struct for holding default client 387/* i2c_client_address_data is the struct for holding default client
@@ -537,7 +565,7 @@ union i2c_smbus_data {
537 /* and one more for user-space compatibility */ 565 /* and one more for user-space compatibility */
538}; 566};
539 567
540/* smbus_access read or write markers */ 568/* i2c_smbus_xfer read or write markers */
541#define I2C_SMBUS_READ 1 569#define I2C_SMBUS_READ 1
542#define I2C_SMBUS_WRITE 0 570#define I2C_SMBUS_WRITE 0
543 571