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Commit 569be443e3c1329fc6725988004f5d8a32fe3be5

Authored by Jean Delvare
Committed by Jean Delvare
1 parent b3af547e19
Exists in master and in 7 other branches imx_3.0.35_4.1.0, imx_3.10.17_1.0.1_ga, imx_3.10.53_1.1.0_ga, imx_3.14.28_1.0.0_ga, smarc-imx_3.10.53_1.1.0_ga, smarc-imx_3.14.28_1.0.0_ga, smarc-l5.0.0_1.0.0-ga

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 <khali@linux-fr.org>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>

Showing 2 changed files with 8 additions and 10 deletions Side-by-side Diff

Documentation/i2c/i2c-stub
Diff comments   View file @ 569be44
... ... @@ -35,9 +35,6 @@
35 35  
36 36 CAVEATS:
37 37  
38   -There are independent arrays for byte/data and word/data commands. Depending
39   -on if/how a target driver mixes them, you'll need to be careful.
40   -
41 38 If your target driver polls some byte or word waiting for it to change, the
42 39 stub could lock it up. Use i2cset to unlock it.
43 40  
drivers/i2c/busses/i2c-stub.c
Diff comments   View file @ 569be44
1 1 /*
2   - i2c-stub.c - Part of lm_sensors, Linux kernel modules for hardware
3   - monitoring
  2 + i2c-stub.c - I2C/SMBus chip emulator
4 3  
5 4 Copyright (c) 2004 Mark M. Hoffman <mhoffman@lightlink.com>
  5 + Copyright (C) 2007 Jean Delvare <khali@linux-fr.org>
6 6  
7 7 This program is free software; you can redistribute it and/or modify
8 8 it under the terms of the GNU General Public License as published by
... ... @@ -37,8 +37,8 @@
37 37  
38 38 struct stub_chip {
39 39 u8 pointer;
40   - u8 bytes[256];
41   - u16 words[256];
  40 + u16 words[256]; /* Byte operations use the LSB as per SMBus
  41 + specification */
42 42 };
43 43  
44 44 static struct stub_chip *stub_chips;
... ... @@ -75,7 +75,7 @@
75 75 "wrote 0x%02x.\n",
76 76 addr, command);
77 77 } else {
78   - data->byte = chip->bytes[chip->pointer++];
  78 + data->byte = chip->words[chip->pointer++] & 0xff;
79 79 dev_dbg(&adap->dev, "smbus byte - addr 0x%02x, "
80 80 "read 0x%02x.\n",
81 81 addr, data->byte);
82 82  
... ... @@ -86,12 +86,13 @@
86 86  
87 87 case I2C_SMBUS_BYTE_DATA:
88 88 if (read_write == I2C_SMBUS_WRITE) {
89   - chip->bytes[command] = data->byte;
  89 + chip->words[command] &= 0xff00;
  90 + chip->words[command] |= data->byte;
90 91 dev_dbg(&adap->dev, "smbus byte data - addr 0x%02x, "
91 92 "wrote 0x%02x at 0x%02x.\n",
92 93 addr, data->byte, command);
93 94 } else {
94   - data->byte = chip->bytes[command];
  95 + data->byte = chip->words[command] & 0xff;
95 96 dev_dbg(&adap->dev, "smbus byte data - addr 0x%02x, "
96 97 "read 0x%02x at 0x%02x.\n",
97 98 addr, data->byte, command);