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[PATCH] i2c: Speed up block transfers

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Speed up i2c_smbus_write_block_data and i2c_smbus_read_i2c_block_data
a bit by using memcpy instead of an explicit loop.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Jean Delvare
2006-01-18 23:14:55 +01:00
committed by Greg Kroah-Hartman
parent 93766d2de6
commit 7656032b90
1 changed files with 6 additions and 9 deletions
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15
drivers/i2c/i2c-core.c
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@@ -920,12 +920,11 @@ s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command,
u8 length, u8 *values) u8 length, u8 *values)
{ {
union i2c_smbus_data data; union i2c_smbus_data data;
int i;
if (length > I2C_SMBUS_BLOCK_MAX) if (length > I2C_SMBUS_BLOCK_MAX)
length = I2C_SMBUS_BLOCK_MAX; length = I2C_SMBUS_BLOCK_MAX;
for (i = 1; i <= length; i++)
data.block[i] = values[i-1];
data.block[0] = length; data.block[0] = length;
memcpy(&data.block[1], values, length);
return i2c_smbus_xfer(client->adapter,client->addr,client->flags, return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
I2C_SMBUS_WRITE,command, I2C_SMBUS_WRITE,command,
I2C_SMBUS_BLOCK_DATA,&data); I2C_SMBUS_BLOCK_DATA,&data);
@@ -935,16 +934,14 @@ s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command,
s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, u8 *values) s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, u8 *values)
{ {
union i2c_smbus_data data; union i2c_smbus_data data;
int i;
if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, if (i2c_smbus_xfer(client->adapter,client->addr,client->flags,
I2C_SMBUS_READ,command, I2C_SMBUS_READ,command,
I2C_SMBUS_I2C_BLOCK_DATA,&data)) I2C_SMBUS_I2C_BLOCK_DATA,&data))
return -1; return -1;
else {
for (i = 1; i <= data.block[0]; i++) memcpy(values, &data.block[1], data.block[0]);
values[i-1] = data.block[i]; return data.block[0];
return data.block[0];
}
} }
s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command, s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command,