diff options
Diffstat (limited to 'drivers/i2c/i2c-core-smbus.c')
| -rw-r--r-- | drivers/i2c/i2c-core-smbus.c | 46 |
1 files changed, 20 insertions, 26 deletions
diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c index f5c9787992e9..d2d32c0fd8c3 100644 --- a/drivers/i2c/i2c-core-smbus.c +++ b/drivers/i2c/i2c-core-smbus.c @@ -323,8 +323,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, */ unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; - int num = read_write == I2C_SMBUS_READ ? 2 : 1; - int i; + int nmsgs = read_write == I2C_SMBUS_READ ? 2 : 1; u8 partial_pec = 0; int status; struct i2c_msg msg[2] = { @@ -340,6 +339,8 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, .buf = msgbuf1, }, }; + bool wants_pec = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK + && size != I2C_SMBUS_I2C_BLOCK_DATA); msgbuf0[0] = command; switch (size) { @@ -348,13 +349,13 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, /* Special case: The read/write field is used as data */ msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? I2C_M_RD : 0); - num = 1; + nmsgs = 1; break; case I2C_SMBUS_BYTE: if (read_write == I2C_SMBUS_READ) { /* Special case: only a read! */ msg[0].flags = I2C_M_RD | flags; - num = 1; + nmsgs = 1; } break; case I2C_SMBUS_BYTE_DATA: @@ -375,7 +376,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, } break; case I2C_SMBUS_PROC_CALL: - num = 2; /* Special case */ + nmsgs = 2; /* Special case */ read_write = I2C_SMBUS_READ; msg[0].len = 3; msg[1].len = 2; @@ -398,12 +399,11 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, } i2c_smbus_try_get_dmabuf(&msg[0], command); - for (i = 1; i < msg[0].len; i++) - msg[0].buf[i] = data->block[i - 1]; + memcpy(msg[0].buf + 1, data->block, msg[0].len - 1); } break; case I2C_SMBUS_BLOCK_PROC_CALL: - num = 2; /* Another special case */ + nmsgs = 2; /* Another special case */ read_write = I2C_SMBUS_READ; if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { dev_err(&adapter->dev, @@ -414,8 +414,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, msg[0].len = data->block[0] + 2; i2c_smbus_try_get_dmabuf(&msg[0], command); - for (i = 1; i < msg[0].len; i++) - msg[0].buf[i] = data->block[i - 1]; + memcpy(msg[0].buf + 1, data->block, msg[0].len - 1); msg[1].flags |= I2C_M_RECV_LEN; msg[1].len = 1; /* block length will be added by @@ -437,8 +436,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, msg[0].len = data->block[0] + 1; i2c_smbus_try_get_dmabuf(&msg[0], command); - for (i = 1; i <= data->block[0]; i++) - msg[0].buf[i] = data->block[i]; + memcpy(msg[0].buf + 1, data->block + 1, data->block[0]); } break; default: @@ -446,33 +444,31 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, return -EOPNOTSUPP; } - i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK - && size != I2C_SMBUS_I2C_BLOCK_DATA); - if (i) { + if (wants_pec) { /* Compute PEC if first message is a write */ if (!(msg[0].flags & I2C_M_RD)) { - if (num == 1) /* Write only */ + if (nmsgs == 1) /* Write only */ i2c_smbus_add_pec(&msg[0]); else /* Write followed by read */ partial_pec = i2c_smbus_msg_pec(0, &msg[0]); } /* Ask for PEC if last message is a read */ - if (msg[num-1].flags & I2C_M_RD) - msg[num-1].len++; + if (msg[nmsgs - 1].flags & I2C_M_RD) + msg[nmsgs - 1].len++; } - status = __i2c_transfer(adapter, msg, num); + status = __i2c_transfer(adapter, msg, nmsgs); if (status < 0) goto cleanup; - if (status != num) { + if (status != nmsgs) { status = -EIO; goto cleanup; } status = 0; /* Check PEC if last message is a read */ - if (i && (msg[num-1].flags & I2C_M_RD)) { - status = i2c_smbus_check_pec(partial_pec, &msg[num-1]); + if (wants_pec && (msg[nmsgs - 1].flags & I2C_M_RD)) { + status = i2c_smbus_check_pec(partial_pec, &msg[nmsgs - 1]); if (status < 0) goto cleanup; } @@ -490,8 +486,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, data->word = msgbuf1[0] | (msgbuf1[1] << 8); break; case I2C_SMBUS_I2C_BLOCK_DATA: - for (i = 0; i < data->block[0]; i++) - data->block[i + 1] = msg[1].buf[i]; + memcpy(data->block + 1, msg[1].buf, data->block[0]); break; case I2C_SMBUS_BLOCK_DATA: case I2C_SMBUS_BLOCK_PROC_CALL: @@ -502,8 +497,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, status = -EPROTO; goto cleanup; } - for (i = 0; i < msg[1].buf[0] + 1; i++) - data->block[i] = msg[1].buf[i]; + memcpy(data->block, msg[1].buf, msg[1].buf[0] + 1); break; } |