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path: root/drivers/i2c/busses/i2c-stub.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-stub.c')
-rw-r--r--drivers/i2c/busses/i2c-stub.c79
1 files changed, 57 insertions, 22 deletions
diff --git a/drivers/i2c/busses/i2c-stub.c b/drivers/i2c/busses/i2c-stub.c
index a54adc50d162..84df29da1ddc 100644
--- a/drivers/i2c/busses/i2c-stub.c
+++ b/drivers/i2c/busses/i2c-stub.c
@@ -24,24 +24,41 @@
24#include <linux/init.h> 24#include <linux/init.h>
25#include <linux/module.h> 25#include <linux/module.h>
26#include <linux/kernel.h> 26#include <linux/kernel.h>
27#include <linux/slab.h>
27#include <linux/errno.h> 28#include <linux/errno.h>
28#include <linux/i2c.h> 29#include <linux/i2c.h>
29 30
30static unsigned short chip_addr; 31#define MAX_CHIPS 10
31module_param(chip_addr, ushort, S_IRUGO);
32MODULE_PARM_DESC(chip_addr, "Chip address (between 0x03 and 0x77)\n");
33 32
34static u8 stub_pointer; 33static unsigned short chip_addr[MAX_CHIPS];
35static u8 stub_bytes[256]; 34module_param_array(chip_addr, ushort, NULL, S_IRUGO);
36static u16 stub_words[256]; 35MODULE_PARM_DESC(chip_addr,
36 "Chip addresses (up to 10, between 0x03 and 0x77)\n");
37
38struct stub_chip {
39 u8 pointer;
40 u8 bytes[256];
41 u16 words[256];
42};
43
44static struct stub_chip *stub_chips;
37 45
38/* Return -1 on error. */ 46/* Return -1 on error. */
39static s32 stub_xfer(struct i2c_adapter * adap, u16 addr, unsigned short flags, 47static s32 stub_xfer(struct i2c_adapter * adap, u16 addr, unsigned short flags,
40 char read_write, u8 command, int size, union i2c_smbus_data * data) 48 char read_write, u8 command, int size, union i2c_smbus_data * data)
41{ 49{
42 s32 ret; 50 s32 ret;
43 51 int i;
44 if (addr != chip_addr) 52 struct stub_chip *chip = NULL;
53
54 /* Search for the right chip */
55 for (i = 0; i < MAX_CHIPS && chip_addr[i]; i++) {
56 if (addr == chip_addr[i]) {
57 chip = stub_chips + i;
58 break;
59 }
60 }
61 if (!chip)
45 return -ENODEV; 62 return -ENODEV;
46 63
47 switch (size) { 64 switch (size) {
@@ -53,12 +70,12 @@ static s32 stub_xfer(struct i2c_adapter * adap, u16 addr, unsigned short flags,
53 70
54 case I2C_SMBUS_BYTE: 71 case I2C_SMBUS_BYTE:
55 if (read_write == I2C_SMBUS_WRITE) { 72 if (read_write == I2C_SMBUS_WRITE) {
56 stub_pointer = command; 73 chip->pointer = command;
57 dev_dbg(&adap->dev, "smbus byte - addr 0x%02x, " 74 dev_dbg(&adap->dev, "smbus byte - addr 0x%02x, "
58 "wrote 0x%02x.\n", 75 "wrote 0x%02x.\n",
59 addr, command); 76 addr, command);
60 } else { 77 } else {
61 data->byte = stub_bytes[stub_pointer++]; 78 data->byte = chip->bytes[chip->pointer++];
62 dev_dbg(&adap->dev, "smbus byte - addr 0x%02x, " 79 dev_dbg(&adap->dev, "smbus byte - addr 0x%02x, "
63 "read 0x%02x.\n", 80 "read 0x%02x.\n",
64 addr, data->byte); 81 addr, data->byte);
@@ -69,29 +86,29 @@ static s32 stub_xfer(struct i2c_adapter * adap, u16 addr, unsigned short flags,
69 86
70 case I2C_SMBUS_BYTE_DATA: 87 case I2C_SMBUS_BYTE_DATA:
71 if (read_write == I2C_SMBUS_WRITE) { 88 if (read_write == I2C_SMBUS_WRITE) {
72 stub_bytes[command] = data->byte; 89 chip->bytes[command] = data->byte;
73 dev_dbg(&adap->dev, "smbus byte data - addr 0x%02x, " 90 dev_dbg(&adap->dev, "smbus byte data - addr 0x%02x, "
74 "wrote 0x%02x at 0x%02x.\n", 91 "wrote 0x%02x at 0x%02x.\n",
75 addr, data->byte, command); 92 addr, data->byte, command);
76 } else { 93 } else {
77 data->byte = stub_bytes[command]; 94 data->byte = chip->bytes[command];
78 dev_dbg(&adap->dev, "smbus byte data - addr 0x%02x, " 95 dev_dbg(&adap->dev, "smbus byte data - addr 0x%02x, "
79 "read 0x%02x at 0x%02x.\n", 96 "read 0x%02x at 0x%02x.\n",
80 addr, data->byte, command); 97 addr, data->byte, command);
81 } 98 }
82 stub_pointer = command + 1; 99 chip->pointer = command + 1;
83 100
84 ret = 0; 101 ret = 0;
85 break; 102 break;
86 103
87 case I2C_SMBUS_WORD_DATA: 104 case I2C_SMBUS_WORD_DATA:
88 if (read_write == I2C_SMBUS_WRITE) { 105 if (read_write == I2C_SMBUS_WRITE) {
89 stub_words[command] = data->word; 106 chip->words[command] = data->word;
90 dev_dbg(&adap->dev, "smbus word data - addr 0x%02x, " 107 dev_dbg(&adap->dev, "smbus word data - addr 0x%02x, "
91 "wrote 0x%04x at 0x%02x.\n", 108 "wrote 0x%04x at 0x%02x.\n",
92 addr, data->word, command); 109 addr, data->word, command);
93 } else { 110 } else {
94 data->word = stub_words[command]; 111 data->word = chip->words[command];
95 dev_dbg(&adap->dev, "smbus word data - addr 0x%02x, " 112 dev_dbg(&adap->dev, "smbus word data - addr 0x%02x, "
96 "read 0x%04x at 0x%02x.\n", 113 "read 0x%04x at 0x%02x.\n",
97 addr, data->word, command); 114 addr, data->word, command);
@@ -129,23 +146,41 @@ static struct i2c_adapter stub_adapter = {
129 146
130static int __init i2c_stub_init(void) 147static int __init i2c_stub_init(void)
131{ 148{
132 if (!chip_addr) { 149 int i, ret;
150
151 if (!chip_addr[0]) {
133 printk(KERN_ERR "i2c-stub: Please specify a chip address\n"); 152 printk(KERN_ERR "i2c-stub: Please specify a chip address\n");
134 return -ENODEV; 153 return -ENODEV;
135 } 154 }
136 if (chip_addr < 0x03 || chip_addr > 0x77) { 155
137 printk(KERN_ERR "i2c-stub: Invalid chip address 0x%02x\n", 156 for (i = 0; i < MAX_CHIPS && chip_addr[i]; i++) {
138 chip_addr); 157 if (chip_addr[i] < 0x03 || chip_addr[i] > 0x77) {
139 return -EINVAL; 158 printk(KERN_ERR "i2c-stub: Invalid chip address "
159 "0x%02x\n", chip_addr[i]);
160 return -EINVAL;
161 }
162
163 printk(KERN_INFO "i2c-stub: Virtual chip at 0x%02x\n",
164 chip_addr[i]);
140 } 165 }
141 166
142 printk(KERN_INFO "i2c-stub: Virtual chip at 0x%02x\n", chip_addr); 167 /* Allocate memory for all chips at once */
143 return i2c_add_adapter(&stub_adapter); 168 stub_chips = kzalloc(i * sizeof(struct stub_chip), GFP_KERNEL);
169 if (!stub_chips) {
170 printk(KERN_ERR "i2c-stub: Out of memory\n");
171 return -ENOMEM;
172 }
173
174 ret = i2c_add_adapter(&stub_adapter);
175 if (ret)
176 kfree(stub_chips);
177 return ret;
144} 178}
145 179
146static void __exit i2c_stub_exit(void) 180static void __exit i2c_stub_exit(void)
147{ 181{
148 i2c_del_adapter(&stub_adapter); 182 i2c_del_adapter(&stub_adapter);
183 kfree(stub_chips);
149} 184}
150 185
151MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>"); 186MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");