omap: Use separate init_irq functions to avoid cpu_is_omap tests early
[linux-2.6.git] / arch / arm / plat-omap / i2c.c
1 /*
2  * linux/arch/arm/plat-omap/i2c.c
3  *
4  * Helper module for board specific I2C bus registration
5  *
6  * Copyright (C) 2007 Nokia Corporation.
7  *
8  * Contact: Jarkko Nikula <jhnikula@gmail.com>
9  *
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.
13  *
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.
18  *
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
22  * 02110-1301 USA
23  *
24  */
25
26 #include <linux/kernel.h>
27 #include <linux/platform_device.h>
28 #include <linux/i2c.h>
29 #include <linux/i2c-omap.h>
30 #include <linux/slab.h>
31 #include <linux/err.h>
32 #include <linux/clk.h>
33
34 #include <mach/irqs.h>
35 #include <plat/mux.h>
36 #include <plat/i2c.h>
37 #include <plat/omap-pm.h>
38 #include <plat/omap_device.h>
39
40 #define OMAP_I2C_SIZE           0x3f
41 #define OMAP1_I2C_BASE          0xfffb3800
42
43 static const char name[] = "omap_i2c";
44
45 #define I2C_RESOURCE_BUILDER(base, irq)                 \
46         {                                               \
47                 .start  = (base),                       \
48                 .end    = (base) + OMAP_I2C_SIZE,       \
49                 .flags  = IORESOURCE_MEM,               \
50         },                                              \
51         {                                               \
52                 .start  = (irq),                        \
53                 .flags  = IORESOURCE_IRQ,               \
54         },
55
56 static struct resource i2c_resources[][2] = {
57         { I2C_RESOURCE_BUILDER(0, 0) },
58 };
59
60 #define I2C_DEV_BUILDER(bus_id, res, data)              \
61         {                                               \
62                 .id     = (bus_id),                     \
63                 .name   = name,                         \
64                 .num_resources  = ARRAY_SIZE(res),      \
65                 .resource       = (res),                \
66                 .dev            = {                     \
67                         .platform_data  = (data),       \
68                 },                                      \
69         }
70
71 #define MAX_OMAP_I2C_HWMOD_NAME_LEN     16
72 #define OMAP_I2C_MAX_CONTROLLERS 4
73 static struct omap_i2c_bus_platform_data i2c_pdata[OMAP_I2C_MAX_CONTROLLERS];
74 static struct platform_device omap_i2c_devices[] = {
75         I2C_DEV_BUILDER(1, i2c_resources[0], &i2c_pdata[0]),
76 };
77
78 #define OMAP_I2C_CMDLINE_SETUP  (BIT(31))
79
80 static int __init omap_i2c_nr_ports(void)
81 {
82         int ports = 0;
83
84         if (cpu_class_is_omap1())
85                 ports = 1;
86         else if (cpu_is_omap24xx())
87                 ports = 2;
88         else if (cpu_is_omap34xx())
89                 ports = 3;
90         else if (cpu_is_omap44xx())
91                 ports = 4;
92
93         return ports;
94 }
95
96 static inline int omap1_i2c_add_bus(int bus_id)
97 {
98         struct platform_device *pdev;
99         struct omap_i2c_bus_platform_data *pdata;
100         struct resource *res;
101
102         omap1_i2c_mux_pins(bus_id);
103
104         pdev = &omap_i2c_devices[bus_id - 1];
105         res = pdev->resource;
106         res[0].start = OMAP1_I2C_BASE;
107         res[0].end = res[0].start + OMAP_I2C_SIZE;
108         res[1].start = INT_I2C;
109         pdata = &i2c_pdata[bus_id - 1];
110
111         return platform_device_register(pdev);
112 }
113
114
115 #ifdef CONFIG_ARCH_OMAP2PLUS
116 /*
117  * XXX This function is a temporary compatibility wrapper - only
118  * needed until the I2C driver can be converted to call
119  * omap_pm_set_max_dev_wakeup_lat() and handle a return code.
120  */
121 static void omap_pm_set_max_mpu_wakeup_lat_compat(struct device *dev, long t)
122 {
123         omap_pm_set_max_mpu_wakeup_lat(dev, t);
124 }
125
126 static struct omap_device_pm_latency omap_i2c_latency[] = {
127         [0] = {
128                 .deactivate_func        = omap_device_idle_hwmods,
129                 .activate_func          = omap_device_enable_hwmods,
130                 .flags                  = OMAP_DEVICE_LATENCY_AUTO_ADJUST,
131         },
132 };
133
134 static inline int omap2_i2c_add_bus(int bus_id)
135 {
136         int l;
137         struct omap_hwmod *oh;
138         struct omap_device *od;
139         char oh_name[MAX_OMAP_I2C_HWMOD_NAME_LEN];
140         struct omap_i2c_bus_platform_data *pdata;
141
142         omap2_i2c_mux_pins(bus_id);
143
144         l = snprintf(oh_name, MAX_OMAP_I2C_HWMOD_NAME_LEN, "i2c%d", bus_id);
145         WARN(l >= MAX_OMAP_I2C_HWMOD_NAME_LEN,
146                 "String buffer overflow in I2C%d device setup\n", bus_id);
147         oh = omap_hwmod_lookup(oh_name);
148         if (!oh) {
149                         pr_err("Could not look up %s\n", oh_name);
150                         return -EEXIST;
151         }
152
153         pdata = &i2c_pdata[bus_id - 1];
154         /*
155          * When waiting for completion of a i2c transfer, we need to
156          * set a wake up latency constraint for the MPU. This is to
157          * ensure quick enough wakeup from idle, when transfer
158          * completes.
159          * Only omap3 has support for constraints
160          */
161         if (cpu_is_omap34xx())
162                 pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
163         od = omap_device_build(name, bus_id, oh, pdata,
164                         sizeof(struct omap_i2c_bus_platform_data),
165                         omap_i2c_latency, ARRAY_SIZE(omap_i2c_latency), 0);
166         WARN(IS_ERR(od), "Could not build omap_device for %s\n", name);
167
168         return PTR_ERR(od);
169 }
170 #else
171 static inline int omap2_i2c_add_bus(int bus_id)
172 {
173         return 0;
174 }
175 #endif
176
177 static int __init omap_i2c_add_bus(int bus_id)
178 {
179         if (cpu_class_is_omap1())
180                 return omap1_i2c_add_bus(bus_id);
181         else
182                 return omap2_i2c_add_bus(bus_id);
183 }
184
185 /**
186  * omap_i2c_bus_setup - Process command line options for the I2C bus speed
187  * @str: String of options
188  *
189  * This function allow to override the default I2C bus speed for given I2C
190  * bus with a command line option.
191  *
192  * Format: i2c_bus=bus_id,clkrate (in kHz)
193  *
194  * Returns 1 on success, 0 otherwise.
195  */
196 static int __init omap_i2c_bus_setup(char *str)
197 {
198         int ports;
199         int ints[3];
200
201         ports = omap_i2c_nr_ports();
202         get_options(str, 3, ints);
203         if (ints[0] < 2 || ints[1] < 1 || ints[1] > ports)
204                 return 0;
205         i2c_pdata[ints[1] - 1].clkrate = ints[2];
206         i2c_pdata[ints[1] - 1].clkrate |= OMAP_I2C_CMDLINE_SETUP;
207
208         return 1;
209 }
210 __setup("i2c_bus=", omap_i2c_bus_setup);
211
212 /*
213  * Register busses defined in command line but that are not registered with
214  * omap_register_i2c_bus from board initialization code.
215  */
216 static int __init omap_register_i2c_bus_cmdline(void)
217 {
218         int i, err = 0;
219
220         for (i = 0; i < ARRAY_SIZE(i2c_pdata); i++)
221                 if (i2c_pdata[i].clkrate & OMAP_I2C_CMDLINE_SETUP) {
222                         i2c_pdata[i].clkrate &= ~OMAP_I2C_CMDLINE_SETUP;
223                         err = omap_i2c_add_bus(i + 1);
224                         if (err)
225                                 goto out;
226                 }
227
228 out:
229         return err;
230 }
231 subsys_initcall(omap_register_i2c_bus_cmdline);
232
233 /**
234  * omap_register_i2c_bus - register I2C bus with device descriptors
235  * @bus_id: bus id counting from number 1
236  * @clkrate: clock rate of the bus in kHz
237  * @info: pointer into I2C device descriptor table or NULL
238  * @len: number of descriptors in the table
239  *
240  * Returns 0 on success or an error code.
241  */
242 int __init omap_register_i2c_bus(int bus_id, u32 clkrate,
243                           struct i2c_board_info const *info,
244                           unsigned len)
245 {
246         int err;
247
248         BUG_ON(bus_id < 1 || bus_id > omap_i2c_nr_ports());
249
250         if (info) {
251                 err = i2c_register_board_info(bus_id, info, len);
252                 if (err)
253                         return err;
254         }
255
256         if (!i2c_pdata[bus_id - 1].clkrate)
257                 i2c_pdata[bus_id - 1].clkrate = clkrate;
258
259         i2c_pdata[bus_id - 1].clkrate &= ~OMAP_I2C_CMDLINE_SETUP;
260
261         return omap_i2c_add_bus(bus_id);
262 }