Subject: i2c-stub: Use a single array for byte and word operations This mimics the behavior of actual SMBus chips better. Signed-off-by: Jean Delvare Cc: Mark M. Hoffman --- Documentation/i2c/i2c-stub | 3 --- drivers/i2c/busses/i2c-stub.c | 15 ++++++++------- 2 files changed, 8 insertions(+), 10 deletions(-) --- linux-2.6.24-rc1.orig/Documentation/i2c/i2c-stub 2007-11-05 09:52:39.000000000 +0100 +++ linux-2.6.24-rc1/Documentation/i2c/i2c-stub 2007-11-05 16:32:17.000000000 +0100 @@ -35,9 +35,6 @@ int chip_addr[10]: CAVEATS: -There are independent arrays for byte/data and word/data commands. Depending -on if/how a target driver mixes them, you'll need to be careful. - If your target driver polls some byte or word waiting for it to change, the stub could lock it up. Use i2cset to unlock it. --- linux-2.6.24-rc1.orig/drivers/i2c/busses/i2c-stub.c 2007-10-24 09:59:28.000000000 +0200 +++ linux-2.6.24-rc1/drivers/i2c/busses/i2c-stub.c 2007-11-05 16:41:06.000000000 +0100 @@ -1,8 +1,8 @@ /* - i2c-stub.c - Part of lm_sensors, Linux kernel modules for hardware - monitoring + i2c-stub.c - I2C/SMBus chip emulator Copyright (c) 2004 Mark M. Hoffman + Copyright (C) 2007 Jean Delvare This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -37,8 +37,8 @@ MODULE_PARM_DESC(chip_addr, struct stub_chip { u8 pointer; - u8 bytes[256]; - u16 words[256]; + u16 words[256]; /* Byte operations use the LSB as per SMBus + specification */ }; static struct stub_chip *stub_chips; @@ -75,7 +75,7 @@ static s32 stub_xfer(struct i2c_adapter "wrote 0x%02x.\n", addr, command); } else { - data->byte = chip->bytes[chip->pointer++]; + data->byte = chip->words[chip->pointer++] & 0xff; dev_dbg(&adap->dev, "smbus byte - addr 0x%02x, " "read 0x%02x.\n", addr, data->byte); @@ -86,12 +86,13 @@ static s32 stub_xfer(struct i2c_adapter case I2C_SMBUS_BYTE_DATA: if (read_write == I2C_SMBUS_WRITE) { - chip->bytes[command] = data->byte; + chip->words[command] &= 0xff00; + chip->words[command] |= data->byte; dev_dbg(&adap->dev, "smbus byte data - addr 0x%02x, " "wrote 0x%02x at 0x%02x.\n", addr, data->byte, command); } else { - data->byte = chip->bytes[command]; + data->byte = chip->words[command] & 0xff; dev_dbg(&adap->dev, "smbus byte data - addr 0x%02x, " "read 0x%02x at 0x%02x.\n", addr, data->byte, command);