1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Helper module for board specific I2C bus registration |
4 | * |
5 | * Copyright (C) 2009 Nokia Corporation. |
6 | */ |
7 | |
8 | #include <linux/i2c.h> |
9 | #include <linux/platform_data/i2c-omap.h> |
10 | |
11 | #include "mux.h" |
12 | #include "soc.h" |
13 | #include "i2c.h" |
14 | |
15 | #define OMAP_I2C_SIZE 0x3f |
16 | #define OMAP1_I2C_BASE 0xfffb3800 |
17 | |
18 | static const char name[] = "omap_i2c" ; |
19 | |
20 | static struct resource i2c_resources[2] = { |
21 | }; |
22 | |
23 | static struct platform_device omap_i2c_devices[1] = { |
24 | }; |
25 | |
26 | static void __init omap1_i2c_mux_pins(int bus_id) |
27 | { |
28 | omap_cfg_reg(reg_cfg: I2C_SDA); |
29 | omap_cfg_reg(reg_cfg: I2C_SCL); |
30 | } |
31 | |
32 | int __init omap_i2c_add_bus(struct omap_i2c_bus_platform_data *pdata, |
33 | int bus_id) |
34 | { |
35 | struct platform_device *pdev; |
36 | struct resource *res; |
37 | |
38 | if (bus_id > 1) |
39 | return -EINVAL; |
40 | |
41 | omap1_i2c_mux_pins(bus_id); |
42 | |
43 | pdev = &omap_i2c_devices[bus_id - 1]; |
44 | pdev->id = bus_id; |
45 | pdev->name = name; |
46 | pdev->num_resources = ARRAY_SIZE(i2c_resources); |
47 | res = i2c_resources; |
48 | res[0].start = OMAP1_I2C_BASE; |
49 | res[0].end = res[0].start + OMAP_I2C_SIZE; |
50 | res[0].flags = IORESOURCE_MEM; |
51 | res[1].start = INT_I2C; |
52 | res[1].flags = IORESOURCE_IRQ; |
53 | pdev->resource = res; |
54 | |
55 | /* all OMAP1 have IP version 1 register set */ |
56 | pdata->rev = OMAP_I2C_IP_VERSION_1; |
57 | |
58 | /* all OMAP1 I2C are implemented like this */ |
59 | pdata->flags = OMAP_I2C_FLAG_NO_FIFO | |
60 | OMAP_I2C_FLAG_SIMPLE_CLOCK | |
61 | OMAP_I2C_FLAG_16BIT_DATA_REG | |
62 | OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK; |
63 | |
64 | /* how the cpu bus is wired up differs for 7xx only */ |
65 | |
66 | pdata->flags |= OMAP_I2C_FLAG_BUS_SHIFT_2; |
67 | |
68 | pdev->dev.platform_data = pdata; |
69 | |
70 | return platform_device_register(pdev); |
71 | } |
72 | |
73 | #define OMAP_I2C_MAX_CONTROLLERS 4 |
74 | static struct omap_i2c_bus_platform_data i2c_pdata[OMAP_I2C_MAX_CONTROLLERS]; |
75 | |
76 | #define OMAP_I2C_CMDLINE_SETUP (BIT(31)) |
77 | |
78 | /** |
79 | * omap_i2c_bus_setup - Process command line options for the I2C bus speed |
80 | * @str: String of options |
81 | * |
82 | * This function allow to override the default I2C bus speed for given I2C |
83 | * bus with a command line option. |
84 | * |
85 | * Format: i2c_bus=bus_id,clkrate (in kHz) |
86 | * |
87 | * Returns 1 on success, 0 otherwise. |
88 | */ |
89 | static int __init omap_i2c_bus_setup(char *str) |
90 | { |
91 | int ints[3]; |
92 | |
93 | get_options(str, nints: 3, ints); |
94 | if (ints[0] < 2 || ints[1] < 1 || |
95 | ints[1] > OMAP_I2C_MAX_CONTROLLERS) |
96 | return 0; |
97 | i2c_pdata[ints[1] - 1].clkrate = ints[2]; |
98 | i2c_pdata[ints[1] - 1].clkrate |= OMAP_I2C_CMDLINE_SETUP; |
99 | |
100 | return 1; |
101 | } |
102 | __setup("i2c_bus=" , omap_i2c_bus_setup); |
103 | |
104 | /* |
105 | * Register busses defined in command line but that are not registered with |
106 | * omap_register_i2c_bus from board initialization code. |
107 | */ |
108 | int __init omap_register_i2c_bus_cmdline(void) |
109 | { |
110 | int i, err = 0; |
111 | |
112 | for (i = 0; i < ARRAY_SIZE(i2c_pdata); i++) |
113 | if (i2c_pdata[i].clkrate & OMAP_I2C_CMDLINE_SETUP) { |
114 | i2c_pdata[i].clkrate &= ~OMAP_I2C_CMDLINE_SETUP; |
115 | err = omap_i2c_add_bus(pdata: &i2c_pdata[i], bus_id: i + 1); |
116 | if (err) |
117 | goto out; |
118 | } |
119 | |
120 | out: |
121 | return err; |
122 | } |
123 | |
124 | /** |
125 | * omap_register_i2c_bus - register I2C bus with device descriptors |
126 | * @bus_id: bus id counting from number 1 |
127 | * @clkrate: clock rate of the bus in kHz |
128 | * @info: pointer into I2C device descriptor table or NULL |
129 | * @len: number of descriptors in the table |
130 | * |
131 | * Returns 0 on success or an error code. |
132 | */ |
133 | int __init omap_register_i2c_bus(int bus_id, u32 clkrate, |
134 | struct i2c_board_info const *info, |
135 | unsigned len) |
136 | { |
137 | int err; |
138 | |
139 | BUG_ON(bus_id < 1 || bus_id > OMAP_I2C_MAX_CONTROLLERS); |
140 | |
141 | if (info) { |
142 | err = i2c_register_board_info(busnum: bus_id, info, n: len); |
143 | if (err) |
144 | return err; |
145 | } |
146 | |
147 | if (!i2c_pdata[bus_id - 1].clkrate) |
148 | i2c_pdata[bus_id - 1].clkrate = clkrate; |
149 | |
150 | i2c_pdata[bus_id - 1].clkrate &= ~OMAP_I2C_CMDLINE_SETUP; |
151 | |
152 | return omap_i2c_add_bus(pdata: &i2c_pdata[bus_id - 1], bus_id); |
153 | } |
154 | |
155 | static int __init omap_i2c_cmdline(void) |
156 | { |
157 | return omap_register_i2c_bus_cmdline(); |
158 | } |
159 | subsys_initcall(omap_i2c_cmdline); |
160 | |