diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-stub.c')
-rw-r--r-- | drivers/i2c/busses/i2c-stub.c | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/drivers/i2c/busses/i2c-stub.c b/drivers/i2c/busses/i2c-stub.c index 73f481e..a54adc5 100644 --- a/drivers/i2c/busses/i2c-stub.c +++ b/drivers/i2c/busses/i2c-stub.c @@ -27,6 +27,10 @@ #include <linux/errno.h> #include <linux/i2c.h> +static unsigned short chip_addr; +module_param(chip_addr, ushort, S_IRUGO); +MODULE_PARM_DESC(chip_addr, "Chip address (between 0x03 and 0x77)\n"); + static u8 stub_pointer; static u8 stub_bytes[256]; static u16 stub_words[256]; @@ -37,6 +41,9 @@ static s32 stub_xfer(struct i2c_adapter * adap, u16 addr, unsigned short flags, { s32 ret; + if (addr != chip_addr) + return -ENODEV; + switch (size) { case I2C_SMBUS_QUICK: @@ -108,7 +115,7 @@ static u32 stub_func(struct i2c_adapter *adapter) I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA; } -static struct i2c_algorithm smbus_algorithm = { +static const struct i2c_algorithm smbus_algorithm = { .functionality = stub_func, .smbus_xfer = stub_xfer, }; @@ -122,7 +129,17 @@ static struct i2c_adapter stub_adapter = { static int __init i2c_stub_init(void) { - printk(KERN_INFO "i2c-stub loaded\n"); + if (!chip_addr) { + printk(KERN_ERR "i2c-stub: Please specify a chip address\n"); + return -ENODEV; + } + if (chip_addr < 0x03 || chip_addr > 0x77) { + printk(KERN_ERR "i2c-stub: Invalid chip address 0x%02x\n", + chip_addr); + return -EINVAL; + } + + printk(KERN_INFO "i2c-stub: Virtual chip at 0x%02x\n", chip_addr); return i2c_add_adapter(&stub_adapter); } |