Commit ba98645c authored by Wolfram Sang's avatar Wolfram Sang Committed by Wolfram Sang

i2c: add i2c_master_{send|recv}_dmasafe

Use the new helper to create variants of i2c_master_{send|recv} which
mark their buffers as DMA safe.
Signed-off-by: default avatarWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 8a91732b
...@@ -80,6 +80,22 @@ static inline int i2c_master_recv(const struct i2c_client *client, ...@@ -80,6 +80,22 @@ static inline int i2c_master_recv(const struct i2c_client *client,
return i2c_transfer_buffer_flags(client, buf, count, I2C_M_RD); 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 * i2c_master_send - issue a single I2C message in master transmit mode
* @client: Handle to slave device * @client: Handle to slave device
...@@ -94,6 +110,22 @@ static inline int i2c_master_send(const struct i2c_client *client, ...@@ -94,6 +110,22 @@ static inline int i2c_master_send(const struct i2c_client *client,
return i2c_transfer_buffer_flags(client, (char *)buf, count, 0); 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. /* Transfer num messages.
*/ */
extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment