xref: /linux/Documentation/i2c/busses/i2c-ocores.rst (revision 906fd46a65383cd639e5eec72a047efc33045d86)
1========================
2Kernel driver i2c-ocores
3========================
4
5Supported adapters:
6  * OpenCores.org I2C controller by Richard Herveille (see datasheet link)
7    https://opencores.org/project/i2c/overview
8
9Author: Peter Korsgaard <peter@korsgaard.com>
10
11Description
12-----------
13
14i2c-ocores is an i2c bus driver for the OpenCores.org I2C controller
15IP core by Richard Herveille.
16
17Usage
18-----
19
20i2c-ocores uses the platform bus, so you need to provide a struct
21platform_device with the base address and interrupt number. The
22dev.platform_data of the device should also point to a struct
23ocores_i2c_platform_data (see linux/platform_data/i2c-ocores.h) describing the
24distance between registers and the input clock speed.
25There is also a possibility to attach a list of i2c_board_info which
26the i2c-ocores driver will add to the bus upon creation.
27
28E.G. something like::
29
30  static struct resource ocores_resources[] = {
31	[0] = {
32		.start	= MYI2C_BASEADDR,
33		.end	= MYI2C_BASEADDR + 8,
34		.flags	= IORESOURCE_MEM,
35	},
36	[1] = {
37		.start	= MYI2C_IRQ,
38		.end	= MYI2C_IRQ,
39		.flags	= IORESOURCE_IRQ,
40	},
41  };
42
43  /* optional board info */
44  struct i2c_board_info ocores_i2c_board_info[] = {
45	{
46		I2C_BOARD_INFO("tsc2003", 0x48),
47		.platform_data = &tsc2003_platform_data,
48		.irq = TSC_IRQ
49	},
50	{
51		I2C_BOARD_INFO("adv7180", 0x42 >> 1),
52		.irq = ADV_IRQ
53	}
54  };
55
56  static struct ocores_i2c_platform_data myi2c_data = {
57	.regstep	= 2,		/* two bytes between registers */
58	.clock_khz	= 50000,	/* input clock of 50MHz */
59	.devices	= ocores_i2c_board_info, /* optional table of devices */
60	.num_devices	= ARRAY_SIZE(ocores_i2c_board_info), /* table size */
61  };
62
63  static struct platform_device myi2c = {
64	.name			= "ocores-i2c",
65	.dev = {
66		.platform_data	= &myi2c_data,
67	},
68	.num_resources		= ARRAY_SIZE(ocores_resources),
69	.resource		= ocores_resources,
70  };
71