2 * linux/arch/arm/plat-omap/i2c.c
4 * Helper module for board specific I2C bus registration
6 * Copyright (C) 2007 Nokia Corporation.
8 * Contact: Jarkko Nikula <jhnikula@gmail.com>
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * version 2 as published by the Free Software Foundation.
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
26 #include <linux/kernel.h>
27 #include <linux/platform_device.h>
28 #include <linux/i2c.h>
29 #include <linux/slab.h>
30 #include <linux/err.h>
31 #include <linux/clk.h>
33 #include <mach/irqs.h>
35 #include <plat/omap_device.h>
37 #define OMAP_I2C_SIZE 0x3f
38 #define OMAP1_I2C_BASE 0xfffb3800
39 #define OMAP1_INT_I2C (32 + 4)
41 static const char name
[] = "omap_i2c";
43 #define I2C_RESOURCE_BUILDER(base, irq) \
46 .end = (base) + OMAP_I2C_SIZE, \
47 .flags = IORESOURCE_MEM, \
51 .flags = IORESOURCE_IRQ, \
54 static struct resource i2c_resources
[][2] = {
55 { I2C_RESOURCE_BUILDER(0, 0) },
58 #define I2C_DEV_BUILDER(bus_id, res, data) \
62 .num_resources = ARRAY_SIZE(res), \
65 .platform_data = (data), \
69 #define MAX_OMAP_I2C_HWMOD_NAME_LEN 16
70 #define OMAP_I2C_MAX_CONTROLLERS 4
71 static struct omap_i2c_bus_platform_data i2c_pdata
[OMAP_I2C_MAX_CONTROLLERS
];
72 static struct platform_device omap_i2c_devices
[] = {
73 I2C_DEV_BUILDER(1, i2c_resources
[0], &i2c_pdata
[0]),
76 #define OMAP_I2C_CMDLINE_SETUP (BIT(31))
78 static int __init
omap_i2c_nr_ports(void)
82 if (cpu_class_is_omap1())
84 else if (cpu_is_omap24xx())
86 else if (cpu_is_omap34xx())
88 else if (cpu_is_omap44xx())
94 static inline int omap1_i2c_add_bus(int bus_id
)
96 struct platform_device
*pdev
;
97 struct omap_i2c_bus_platform_data
*pdata
;
100 omap1_i2c_mux_pins(bus_id
);
102 pdev
= &omap_i2c_devices
[bus_id
- 1];
103 res
= pdev
->resource
;
104 res
[0].start
= OMAP1_I2C_BASE
;
105 res
[0].end
= res
[0].start
+ OMAP_I2C_SIZE
;
106 res
[1].start
= OMAP1_INT_I2C
;
107 pdata
= &i2c_pdata
[bus_id
- 1];
109 /* all OMAP1 have IP version 1 register set */
110 pdata
->rev
= OMAP_I2C_IP_VERSION_1
;
112 /* all OMAP1 I2C are implemented like this */
113 pdata
->flags
= OMAP_I2C_FLAG_NO_FIFO
|
114 OMAP_I2C_FLAG_SIMPLE_CLOCK
|
115 OMAP_I2C_FLAG_16BIT_DATA_REG
|
116 OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK
;
118 /* how the cpu bus is wired up differs for 7xx only */
120 if (cpu_is_omap7xx())
121 pdata
->flags
|= OMAP_I2C_FLAG_BUS_SHIFT_1
;
123 pdata
->flags
|= OMAP_I2C_FLAG_BUS_SHIFT_2
;
125 return platform_device_register(pdev
);
129 #ifdef CONFIG_ARCH_OMAP2PLUS
130 static inline int omap2_i2c_add_bus(int bus_id
)
133 struct omap_hwmod
*oh
;
134 struct platform_device
*pdev
;
135 char oh_name
[MAX_OMAP_I2C_HWMOD_NAME_LEN
];
136 struct omap_i2c_bus_platform_data
*pdata
;
137 struct omap_i2c_dev_attr
*dev_attr
;
139 omap2_i2c_mux_pins(bus_id
);
141 l
= snprintf(oh_name
, MAX_OMAP_I2C_HWMOD_NAME_LEN
, "i2c%d", bus_id
);
142 WARN(l
>= MAX_OMAP_I2C_HWMOD_NAME_LEN
,
143 "String buffer overflow in I2C%d device setup\n", bus_id
);
144 oh
= omap_hwmod_lookup(oh_name
);
146 pr_err("Could not look up %s\n", oh_name
);
150 pdata
= &i2c_pdata
[bus_id
- 1];
152 * pass the hwmod class's CPU-specific knowledge of I2C IP revision in
153 * use, and functionality implementation flags, up to the OMAP I2C
154 * driver via platform data
156 pdata
->rev
= oh
->class->rev
;
158 dev_attr
= (struct omap_i2c_dev_attr
*)oh
->dev_attr
;
159 pdata
->flags
= dev_attr
->flags
;
161 pdev
= omap_device_build(name
, bus_id
, oh
, pdata
,
162 sizeof(struct omap_i2c_bus_platform_data
),
164 WARN(IS_ERR(pdev
), "Could not build omap_device for %s\n", name
);
166 return PTR_RET(pdev
);
169 static inline int omap2_i2c_add_bus(int bus_id
)
175 static int __init
omap_i2c_add_bus(int bus_id
)
177 if (cpu_class_is_omap1())
178 return omap1_i2c_add_bus(bus_id
);
180 return omap2_i2c_add_bus(bus_id
);
184 * omap_i2c_bus_setup - Process command line options for the I2C bus speed
185 * @str: String of options
187 * This function allow to override the default I2C bus speed for given I2C
188 * bus with a command line option.
190 * Format: i2c_bus=bus_id,clkrate (in kHz)
192 * Returns 1 on success, 0 otherwise.
194 static int __init
omap_i2c_bus_setup(char *str
)
199 ports
= omap_i2c_nr_ports();
200 get_options(str
, 3, ints
);
201 if (ints
[0] < 2 || ints
[1] < 1 || ints
[1] > ports
)
203 i2c_pdata
[ints
[1] - 1].clkrate
= ints
[2];
204 i2c_pdata
[ints
[1] - 1].clkrate
|= OMAP_I2C_CMDLINE_SETUP
;
208 __setup("i2c_bus=", omap_i2c_bus_setup
);
211 * Register busses defined in command line but that are not registered with
212 * omap_register_i2c_bus from board initialization code.
214 static int __init
omap_register_i2c_bus_cmdline(void)
218 for (i
= 0; i
< ARRAY_SIZE(i2c_pdata
); i
++)
219 if (i2c_pdata
[i
].clkrate
& OMAP_I2C_CMDLINE_SETUP
) {
220 i2c_pdata
[i
].clkrate
&= ~OMAP_I2C_CMDLINE_SETUP
;
221 err
= omap_i2c_add_bus(i
+ 1);
229 subsys_initcall(omap_register_i2c_bus_cmdline
);
232 * omap_register_i2c_bus - register I2C bus with device descriptors
233 * @bus_id: bus id counting from number 1
234 * @clkrate: clock rate of the bus in kHz
235 * @info: pointer into I2C device descriptor table or NULL
236 * @len: number of descriptors in the table
238 * Returns 0 on success or an error code.
240 int __init
omap_register_i2c_bus(int bus_id
, u32 clkrate
,
241 struct i2c_board_info
const *info
,
246 BUG_ON(bus_id
< 1 || bus_id
> omap_i2c_nr_ports());
249 err
= i2c_register_board_info(bus_id
, info
, len
);
254 if (!i2c_pdata
[bus_id
- 1].clkrate
)
255 i2c_pdata
[bus_id
- 1].clkrate
= clkrate
;
257 i2c_pdata
[bus_id
- 1].clkrate
&= ~OMAP_I2C_CMDLINE_SETUP
;
259 return omap_i2c_add_bus(bus_id
);