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Diffstat (limited to 'include/linux/i2c.h')
-rw-r--r--include/linux/i2c.h112
1 files changed, 88 insertions, 24 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 0f774406fad0..419a38e7c315 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -55,7 +55,7 @@ typedef int (*i2c_slave_cb_t)(struct i2c_client *, enum i2c_slave_event, u8 *);
struct module;
struct property_entry;
-#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
+#if IS_ENABLED(CONFIG_I2C)
/*
* The master routines are the ones normally used to transmit data to devices
* on a bus (or read from them). Apart from two basic transfer functions to
@@ -63,10 +63,68 @@ struct property_entry;
* transmit an arbitrary number of messages without interruption.
* @count must be be less than 64k since msg.len is u16.
*/
-extern int i2c_master_send(const struct i2c_client *client, const char *buf,
- int count);
-extern int i2c_master_recv(const struct i2c_client *client, char *buf,
- int count);
+extern int i2c_transfer_buffer_flags(const struct i2c_client *client,
+ char *buf, int count, u16 flags);
+
+/**
+ * i2c_master_recv - issue a single I2C message in master receive mode
+ * @client: Handle to slave device
+ * @buf: Where to store data read from slave
+ * @count: How many bytes to read, must be less than 64k since msg.len is u16
+ *
+ * Returns negative errno, or else the number of bytes read.
+ */
+static inline int i2c_master_recv(const struct i2c_client *client,
+ char *buf, int count)
+{
+ return i2c_transfer_buffer_flags(client, buf, count, I2C_M_RD);
+};
+
+/**
+ * i2c_master_recv_dmasafe - issue a single I2C message in master receive mode
+ * using a DMA safe buffer
+ * @client: Handle to slave device
+ * @buf: Where to store data read from slave, must be safe to use with DMA
+ * @count: How many bytes to read, must be less than 64k since msg.len is u16
+ *
+ * Returns negative errno, or else the number of bytes read.
+ */
+static inline int i2c_master_recv_dmasafe(const struct i2c_client *client,
+ char *buf, int count)
+{
+ return i2c_transfer_buffer_flags(client, buf, count,
+ I2C_M_RD | I2C_M_DMA_SAFE);
+};
+
+/**
+ * i2c_master_send - issue a single I2C message in master transmit mode
+ * @client: Handle to slave device
+ * @buf: Data that will be written to the slave
+ * @count: How many bytes to write, must be less than 64k since msg.len is u16
+ *
+ * Returns negative errno, or else the number of bytes written.
+ */
+static inline int i2c_master_send(const struct i2c_client *client,
+ const char *buf, int count)
+{
+ return i2c_transfer_buffer_flags(client, (char *)buf, count, 0);
+};
+
+/**
+ * i2c_master_send_dmasafe - issue a single I2C message in master transmit mode
+ * using a DMA safe buffer
+ * @client: Handle to slave device
+ * @buf: Data that will be written to the slave, must be safe to use with DMA
+ * @count: How many bytes to write, must be less than 64k since msg.len is u16
+ *
+ * Returns negative errno, or else the number of bytes written.
+ */
+static inline int i2c_master_send_dmasafe(const struct i2c_client *client,
+ const char *buf, int count)
+{
+ return i2c_transfer_buffer_flags(client, (char *)buf, count,
+ I2C_M_DMA_SAFE);
+};
/* Transfer num messages.
*/
@@ -354,7 +412,7 @@ struct i2c_board_info {
.type = dev_type, .addr = (dev_addr)
-#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
+#if IS_ENABLED(CONFIG_I2C)
/* Add-on boards should register/unregister their devices; e.g. a board
* with integrated I2C, a config eeprom, sensors, and a codec that's
* used in conjunction with the primary hardware.
@@ -485,40 +543,43 @@ struct i2c_timings {
/**
* struct i2c_bus_recovery_info - I2C bus recovery information
* @recover_bus: Recover routine. Either pass driver's recover_bus() routine, or
- * i2c_generic_scl_recovery() or i2c_generic_gpio_recovery().
+ * i2c_generic_scl_recovery().
* @get_scl: This gets current value of SCL line. Mandatory for generic SCL
- * recovery. Used internally for generic GPIO recovery.
- * @set_scl: This sets/clears SCL line. Mandatory for generic SCL recovery. Used
- * internally for generic GPIO recovery.
+ * recovery. Populated internally for generic GPIO recovery.
+ * @set_scl: This sets/clears the SCL line. Mandatory for generic SCL recovery.
+ * Populated internally for generic GPIO recovery.
* @get_sda: This gets current value of SDA line. Optional for generic SCL
- * recovery. Used internally, if sda_gpio is a valid GPIO, for generic GPIO
- * recovery.
+ * recovery. Populated internally, if sda_gpio is a valid GPIO, for generic
+ * GPIO recovery.
+ * @set_sda: This sets/clears the SDA line. Optional for generic SCL recovery.
+ * Populated internally, if sda_gpio is a valid GPIO, for generic GPIO
+ * recovery.
* @prepare_recovery: This will be called before starting recovery. Platform may
* configure padmux here for SDA/SCL line or something else they want.
* @unprepare_recovery: This will be called after completing recovery. Platform
* may configure padmux here for SDA/SCL line or something else they want.
- * @scl_gpio: gpio number of the SCL line. Only required for GPIO recovery.
- * @sda_gpio: gpio number of the SDA line. Only required for GPIO recovery.
+ * @scl_gpiod: gpiod of the SCL line. Only required for GPIO recovery.
+ * @sda_gpiod: gpiod of the SDA line. Only required for GPIO recovery.
*/
struct i2c_bus_recovery_info {
- int (*recover_bus)(struct i2c_adapter *);
+ int (*recover_bus)(struct i2c_adapter *adap);
- int (*get_scl)(struct i2c_adapter *);
- void (*set_scl)(struct i2c_adapter *, int val);
- int (*get_sda)(struct i2c_adapter *);
+ int (*get_scl)(struct i2c_adapter *adap);
+ void (*set_scl)(struct i2c_adapter *adap, int val);
+ int (*get_sda)(struct i2c_adapter *adap);
+ void (*set_sda)(struct i2c_adapter *adap, int val);
- void (*prepare_recovery)(struct i2c_adapter *);
- void (*unprepare_recovery)(struct i2c_adapter *);
+ void (*prepare_recovery)(struct i2c_adapter *adap);
+ void (*unprepare_recovery)(struct i2c_adapter *adap);
/* gpio recovery */
- int scl_gpio;
- int sda_gpio;
+ struct gpio_desc *scl_gpiod;
+ struct gpio_desc *sda_gpiod;
};
int i2c_recover_bus(struct i2c_adapter *adap);
/* Generic recovery routines */
-int i2c_generic_gpio_recovery(struct i2c_adapter *adap);
int i2c_generic_scl_recovery(struct i2c_adapter *adap);
/**
@@ -706,7 +767,7 @@ i2c_unlock_adapter(struct i2c_adapter *adapter)
/* administration...
*/
-#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
+#if IS_ENABLED(CONFIG_I2C)
extern int i2c_add_adapter(struct i2c_adapter *);
extern void i2c_del_adapter(struct i2c_adapter *);
extern int i2c_add_numbered_adapter(struct i2c_adapter *);
@@ -769,6 +830,9 @@ static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg)
return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0);
}
+u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold);
+void i2c_release_dma_safe_msg_buf(struct i2c_msg *msg, u8 *buf);
+
int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr);
/**
* module_i2c_driver() - Helper macro for registering a modular I2C driver