intelfb: add preliminary i2c support
[linux-2.6.git] / drivers / video / intelfb / intelfb_i2c.c
1 /**************************************************************************
2
3  Copyright 2006 Dave Airlie <airlied@linux.ie>
4
5 All Rights Reserved.
6
7 Permission is hereby granted, free of charge, to any person obtaining a
8 copy of this software and associated documentation files (the "Software"),
9 to deal in the Software without restriction, including without limitation
10 on the rights to use, copy, modify, merge, publish, distribute, sub
11 license, and/or sell copies of the Software, and to permit persons to whom
12 the Software is furnished to do so, subject to the following conditions:
13
14 The above copyright notice and this permission notice (including the next
15 paragraph) shall be included in all copies or substantial portions of the
16 Software.
17
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 THE COPYRIGHT HOLDERS AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 USE OR OTHER DEALINGS IN THE SOFTWARE.
25
26 **************************************************************************/
27
28 #include <linux/config.h>
29 #include <linux/module.h>
30 #include <linux/kernel.h>
31 #include <linux/sched.h>
32 #include <linux/delay.h>
33 #include <linux/pci.h>
34 #include <linux/fb.h>
35
36 #include <linux/i2c.h>
37 #include <linux/i2c-id.h>
38 #include <linux/i2c-algo-bit.h>
39
40 #include <asm/io.h>
41
42 #include "intelfb.h"
43 #include "intelfbhw.h"
44
45 /* bit locations in the registers */
46 #define SCL_DIR_MASK            0x0001
47 #define SCL_DIR                 0x0002
48 #define SCL_VAL_MASK            0x0004
49 #define SCL_VAL_OUT             0x0008
50 #define SCL_VAL_IN              0x0010
51 #define SDA_DIR_MASK            0x0100
52 #define SDA_DIR                 0x0200
53 #define SDA_VAL_MASK            0x0400
54 #define SDA_VAL_OUT             0x0800
55 #define SDA_VAL_IN              0x1000
56
57 static void intelfb_gpio_setscl(void *data, int state)
58 {
59         struct intelfb_i2c_chan *chan = data;
60         struct intelfb_info *dinfo = chan->dinfo;
61         u32 val;
62
63         OUTREG(chan->reg, (state ? SCL_VAL_OUT : 0) | SCL_DIR | SCL_DIR_MASK | SCL_VAL_MASK);
64         val = INREG(chan->reg);
65 }
66
67 static void intelfb_gpio_setsda(void *data, int state)
68 {
69         struct intelfb_i2c_chan *chan = data;
70         struct intelfb_info *dinfo = chan->dinfo;
71         u32 val;
72
73         OUTREG(chan->reg, (state ? SDA_VAL_OUT : 0) | SDA_DIR | SDA_DIR_MASK | SDA_VAL_MASK);
74         val = INREG(chan->reg);
75 }
76
77 static int intelfb_gpio_getscl(void *data)
78 {
79         struct intelfb_i2c_chan *chan = data;
80         struct intelfb_info *dinfo = chan->dinfo;
81         u32 val;
82
83         OUTREG(chan->reg, SCL_DIR_MASK);
84         OUTREG(chan->reg, 0);
85         val = INREG(chan->reg);
86         return ((val & SCL_VAL_IN) != 0);
87 }
88
89 static int intelfb_gpio_getsda(void *data)
90 {
91         struct intelfb_i2c_chan *chan = data;
92         struct intelfb_info *dinfo = chan->dinfo;
93         u32 val;
94
95         OUTREG(chan->reg, SDA_DIR_MASK);
96         OUTREG(chan->reg, 0);
97         val = INREG(chan->reg);
98         return ((val & SDA_VAL_IN) != 0);
99 }
100
101 static int intelfb_setup_i2c_bus(struct intelfb_info *dinfo,
102                                                                  struct intelfb_i2c_chan *chan,
103                                                                  const u32 reg, const char *name)
104 {
105         int rc;
106
107         chan->dinfo                                     = dinfo;
108         chan->reg                                       = reg;
109         snprintf(chan->adapter.name, I2C_NAME_SIZE, "intelfb %s", name);
110         chan->adapter.owner                     = THIS_MODULE;
111         chan->adapter.id                        = I2C_HW_B_INTELFB;
112         chan->adapter.algo_data         = &chan->algo;
113         chan->adapter.dev.parent        = &chan->dinfo->pdev->dev;
114         chan->algo.setsda                       = intelfb_gpio_setsda;
115         chan->algo.setscl                       = intelfb_gpio_setscl;
116         chan->algo.getsda                       = intelfb_gpio_getsda;
117         chan->algo.getscl                       = intelfb_gpio_getscl;
118         chan->algo.udelay                       = 40;
119         chan->algo.timeout                      = 20;
120         chan->algo.data                         = chan;
121
122         i2c_set_adapdata(&chan->adapter, chan);
123
124         /* Raise SCL and SDA */
125         intelfb_gpio_setsda(chan, 1);
126         intelfb_gpio_setscl(chan, 1);
127         udelay(20);
128
129         rc = i2c_bit_add_bus(&chan->adapter);
130         if (rc == 0)
131                 DBG_MSG("I2C bus %s registered.\n", name);
132         else
133                 WRN_MSG("Failed to register I2C bus %s.\n", name);
134         return rc;
135 }
136
137 void intelfb_create_i2c_busses(struct intelfb_info *dinfo)
138 {
139         int i = 0;
140
141         /* everyone has at least a single analog output */
142         dinfo->num_outputs = 1;
143         dinfo->output[i].type = INTELFB_OUTPUT_ANALOG;
144
145         /* setup the DDC bus for analog output */
146         intelfb_setup_i2c_bus(dinfo, &dinfo->output[i].ddc_bus, GPIOA, "CRTDDC_A");
147         i++;
148
149     /* need to add the output busses for each device
150        - this function is very incomplete
151        - i915GM has LVDS and TVOUT for example
152     */
153     switch(dinfo->chipset) {
154         case INTEL_830M:
155         case INTEL_845G:
156         case INTEL_855GM:
157         case INTEL_865G:
158                 dinfo->output[i].type = INTELFB_OUTPUT_DVO;
159                 intelfb_setup_i2c_bus(dinfo, &dinfo->output[i].ddc_bus, GPIOD, "DVODDC_D");
160                 intelfb_setup_i2c_bus(dinfo, &dinfo->output[i].i2c_bus, GPIOE, "DVOI2C_E");
161                 i++;
162                 break;
163         case INTEL_915G:
164         case INTEL_915GM:
165                 /* has  some LVDS + tv-out */
166         case INTEL_945G:
167         case INTEL_945GM:
168                 /* SDVO ports have a single control bus - 2 devices */
169                 dinfo->output[i].type = INTELFB_OUTPUT_SDVO;
170                 intelfb_setup_i2c_bus(dinfo, &dinfo->output[i].i2c_bus, GPIOE, "SDVOCTRL_E");
171                 /* TODO: initialize the SDVO */
172 //              I830SDVOInit(pScrn, i, DVOB);
173                 i++;
174
175                 /* set up SDVOC */
176                 dinfo->output[i].type = INTELFB_OUTPUT_SDVO;
177                 dinfo->output[i].i2c_bus = dinfo->output[i - 1].i2c_bus;
178                 /* TODO: initialize the SDVO */
179 //              I830SDVOInit(pScrn, i, DVOC);
180                 i++;
181                 break;
182         }
183         dinfo->num_outputs = i;
184 }