Commit 87cf5127 authored by Quan Nguyen's avatar Quan Nguyen Committed by Wolfram Sang

i2c: core-smbus: Expose PEC calculate function for generic use

Expose the PEC calculation i2c_smbus_pec() for generic use.
Signed-off-by: default avatarQuan Nguyen <quan@os.amperecomputing.com>
Acked-by: default avatarMatt Johnston <matt@codeconstruct.com.au>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent 31df7195
......@@ -37,8 +37,15 @@ static u8 crc8(u16 data)
return (u8)(data >> 8);
}
/* Incremental CRC8 over count bytes in the array pointed to by p */
static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count)
/**
* i2c_smbus_pec - Incremental CRC8 over the given input data array
* @crc: previous return crc8 value
* @p: pointer to data buffer.
* @count: number of bytes in data buffer.
*
* Incremental CRC8 over count bytes in the array pointed to by p
*/
u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count)
{
int i;
......@@ -46,6 +53,7 @@ static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count)
crc = crc8((crc ^ p[i]) << 8);
return crc;
}
EXPORT_SYMBOL(i2c_smbus_pec);
/* Assume a 7-bit address, which is reasonable for SMBus */
static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg)
......
......@@ -148,6 +148,7 @@ s32 __i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
/* Now follow the 'nice' access routines. These also document the calling
conventions of i2c_smbus_xfer. */
u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count);
s32 i2c_smbus_read_byte(const struct i2c_client *client);
s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value);
s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command);
......
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