i2c: smbus: switch from loops to memcpy

When copying memory from one buffer to another, instead of open-coding
loops with byte-by-byte copies let's use memcpy() which might be a bit
faster and makes intent more clear.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
index f5c9787992e96d520cc884e88d06eb0c179c10a3..bf6bfe7c5cfe139f252f768b1756f6e240679b74 100644 (file)
--- a/drivers/i2c/i2c-core-smbus.c
+++ b/drivers/i2c/i2c-core-smbus.c
@@ -398,8 +398,7 @@ 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:
@@ -414,8 +413,7 @@ 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 +435,7 @@ 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:
@@ -490,8 +487,7 @@ 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 +498,7 @@ 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;
                }