I2C slave interface drivers have to calculate the PEC themselves
in the i2c slave event handler. This will be used for an in-progress
driver for MCTP I2C transport.
Signed-off-by: Matt Johnston <matt@xxxxxxxxxxxxxxxxxxxx>
---
drivers/i2c/i2c-core-smbus.c | 3 ++-
include/linux/i2c.h | 2 ++
2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
index d2d32c0fd8c3..27a06b80decb 100644
--- a/drivers/i2c/i2c-core-smbus.c
+++ b/drivers/i2c/i2c-core-smbus.c
@@ -38,7 +38,7 @@ static u8 crc8(u16 data)
}
/* Incremental CRC8 over count bytes in the array pointed to by p */
-static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count)
+u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count)
{
int i;
@@ -46,6 +46,7 @@ static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count)
crc = crc8((crc ^ p[i]) << 8);
return crc;
}
+EXPORT_SYMBOL_GPL(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)
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index e8f2ac8c9c3d..9e5e5e8192c3 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -186,6 +186,8 @@ s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client,
u8 *values);
int i2c_get_device_id(const struct i2c_client *client,
struct i2c_device_identity *id);
+
+u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count);
#endif /* I2C */
/**
--
2.30.2
