Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ]
Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  * linux/drivers/video/savage/savagefb-i2c.c - S3 Savage DDC2
  3  *
  4  * Copyright 2004 Antonino A. Daplas <adaplas @pol.net>
  5  *
  6  * Based partly on rivafb-i2c.c
  7  *
  8  * This file is subject to the terms and conditions of the GNU General Public
  9  * License.  See the file COPYING in the main directory of this archive
 10  * for more details.
 11  */
 12 
 13 #include <linux/config.h>
 14 #include <linux/module.h>
 15 #include <linux/kernel.h>
 16 #include <linux/sched.h>
 17 #include <linux/delay.h>
 18 #include <linux/pci.h>
 19 #include <linux/fb.h>
 20 
 21 #include <asm/io.h>
 22 #include "savagefb.h"
 23 
 24 #define SAVAGE_DDC      0x50
 25 
 26 #define VGA_CR_IX       0x3d4
 27 #define VGA_CR_DATA     0x3d5
 28 
 29 #define CR_SERIAL1      0xa0    /* I2C serial communications interface */
 30 #define MM_SERIAL1      0xff20
 31 #define CR_SERIAL2      0xb1    /* DDC2 monitor communications interface */
 32 
 33 /* based on vt8365 documentation */
 34 #define PROSAVAGE_I2C_ENAB      0x10
 35 #define PROSAVAGE_I2C_SCL_OUT   0x01
 36 #define PROSAVAGE_I2C_SDA_OUT   0x02
 37 #define PROSAVAGE_I2C_SCL_IN    0x04
 38 #define PROSAVAGE_I2C_SDA_IN    0x08
 39 
 40 #define SAVAGE4_I2C_ENAB        0x00000020
 41 #define SAVAGE4_I2C_SCL_OUT     0x00000001
 42 #define SAVAGE4_I2C_SDA_OUT     0x00000002
 43 #define SAVAGE4_I2C_SCL_IN      0x00000008
 44 #define SAVAGE4_I2C_SDA_IN      0x00000010
 45 
 46 #define SET_CR_IX(base, val)    writeb((val), base + 0x8000 + VGA_CR_IX)
 47 #define SET_CR_DATA(base, val)  writeb((val), base + 0x8000 + VGA_CR_DATA)
 48 #define GET_CR_DATA(base)       readb(base + 0x8000 + VGA_CR_DATA)
 49 
 50 static void savage4_gpio_setscl(void *data, int val)
 51 {
 52         struct savagefb_i2c_chan *chan = (struct savagefb_i2c_chan *)data;
 53         unsigned int r;
 54 
 55         r = readl(chan->ioaddr + chan->reg);
 56         if(val)
 57                 r |= SAVAGE4_I2C_SCL_OUT;
 58         else
 59                 r &= ~SAVAGE4_I2C_SCL_OUT;
 60         writel(r, chan->ioaddr + chan->reg);
 61         readl(chan->ioaddr + chan->reg);        /* flush posted write */
 62 }
 63 
 64 static void savage4_gpio_setsda(void *data, int val)
 65 {
 66         struct savagefb_i2c_chan *chan = (struct savagefb_i2c_chan *)data;
 67 
 68         unsigned int r;
 69         r = readl(chan->ioaddr + chan->reg);
 70         if(val)
 71                 r |= SAVAGE4_I2C_SDA_OUT;
 72         else
 73                 r &= ~SAVAGE4_I2C_SDA_OUT;
 74         writel(r, chan->ioaddr + chan->reg);
 75         readl(chan->ioaddr + chan->reg);        /* flush posted write */
 76 }
 77 
 78 static int savage4_gpio_getscl(void *data)
 79 {
 80         struct savagefb_i2c_chan *chan = (struct savagefb_i2c_chan *)data;
 81 
 82         return (0 != (readl(chan->ioaddr + chan->reg) & SAVAGE4_I2C_SCL_IN));
 83 }
 84 
 85 static int savage4_gpio_getsda(void *data)
 86 {
 87         struct savagefb_i2c_chan *chan = (struct savagefb_i2c_chan *)data;
 88 
 89         return (0 != (readl(chan->ioaddr + chan->reg) & SAVAGE4_I2C_SDA_IN));
 90 }
 91 
 92 static void prosavage_gpio_setscl(void* data, int val)
 93 {
 94         struct savagefb_i2c_chan *chan = (struct savagefb_i2c_chan *)data;
 95         u32                       r;
 96 
 97         SET_CR_IX(chan->ioaddr, chan->reg);
 98         r = GET_CR_DATA(chan->ioaddr);
 99         r |= PROSAVAGE_I2C_ENAB;
100         if (val) {
101                 r |= PROSAVAGE_I2C_SCL_OUT;
102         } else {
103                 r &= ~PROSAVAGE_I2C_SCL_OUT;
104         }
105         SET_CR_DATA(chan->ioaddr, r);
106 }
107 
108 static void prosavage_gpio_setsda(void* data, int val)
109 {
110         struct savagefb_i2c_chan *chan = (struct savagefb_i2c_chan *)data;
111         unsigned int r;
112 
113         SET_CR_IX(chan->ioaddr, chan->reg);
114         r = GET_CR_DATA(chan->ioaddr);
115         r |= PROSAVAGE_I2C_ENAB;
116         if (val) {
117                 r |= PROSAVAGE_I2C_SDA_OUT;
118         } else {
119                 r &= ~PROSAVAGE_I2C_SDA_OUT;
120         }
121         SET_CR_DATA(chan->ioaddr, r);
122 }
123 
124 static int prosavage_gpio_getscl(void* data)
125 {
126         struct savagefb_i2c_chan *chan = (struct savagefb_i2c_chan *)data;
127 
128         SET_CR_IX(chan->ioaddr, chan->reg);
129         return (0 != (GET_CR_DATA(chan->ioaddr) & PROSAVAGE_I2C_SCL_IN));
130 }
131 
132 static int prosavage_gpio_getsda(void* data)
133 {
134         struct savagefb_i2c_chan *chan = (struct savagefb_i2c_chan *)data;
135 
136         SET_CR_IX(chan->ioaddr, chan->reg);
137         return (0 != (GET_CR_DATA(chan->ioaddr) & PROSAVAGE_I2C_SDA_IN));
138 }
139 
140 #define I2C_ALGO_SAVAGE   0x0f0000
141 static int savage_setup_i2c_bus(struct savagefb_i2c_chan *chan,
142                                 const char *name)
143 {
144         int (*add_bus)(struct i2c_adapter *) = symbol_get(i2c_bit_add_bus);
145         int rc = 0;
146 
147         if (add_bus && chan->par) {
148                 strcpy(chan->adapter.name, name);
149                 chan->adapter.owner             = THIS_MODULE;
150                 chan->adapter.id                = I2C_ALGO_SAVAGE;
151                 chan->adapter.algo_data         = &chan->algo;
152                 chan->adapter.dev.parent        = &chan->par->pcidev->dev;
153                 chan->algo.udelay               = 40;
154                 chan->algo.mdelay               = 5;
155                 chan->algo.timeout              = 20;
156                 chan->algo.data                 = chan;
157 
158                 i2c_set_adapdata(&chan->adapter, chan);
159 
160                 /* Raise SCL and SDA */
161                 chan->algo.setsda(chan, 1);
162                 chan->algo.setscl(chan, 1);
163                 udelay(20);
164 
165                 rc = add_bus(&chan->adapter);
166 
167                 if (rc == 0)
168                         dev_dbg(&chan->par->pcidev->dev,
169                                 "I2C bus %s registered.\n", name);
170                 else
171                         dev_warn(&chan->par->pcidev->dev,
172                                  "Failed to register I2C bus %s.\n", name);
173 
174                 symbol_put(i2c_bit_add_bus);
175         } else
176                 chan->par = NULL;
177 
178         return rc;
179 }
180 
181 void savagefb_create_i2c_busses(struct fb_info *info)
182 {
183         struct savagefb_par *par = (struct savagefb_par *)info->par;
184         par->chan.par   = par;
185 
186         switch(info->fix.accel) {
187         case FB_ACCEL_PROSAVAGE_DDRK:
188         case FB_ACCEL_PROSAVAGE_PM:
189                 par->chan.reg         = CR_SERIAL2;
190                 par->chan.ioaddr      = par->mmio.vbase;
191                 par->chan.algo.setsda = prosavage_gpio_setsda;
192                 par->chan.algo.setscl = prosavage_gpio_setscl;
193                 par->chan.algo.getsda = prosavage_gpio_getsda;
194                 par->chan.algo.getscl = prosavage_gpio_getscl;
195                 break;
196         case FB_ACCEL_SAVAGE4:
197                 par->chan.reg         = 0xff20;
198                 par->chan.ioaddr      = par->mmio.vbase;
199                 par->chan.algo.setsda = savage4_gpio_setsda;
200                 par->chan.algo.setscl = savage4_gpio_setscl;
201                 par->chan.algo.getsda = savage4_gpio_getsda;
202                 par->chan.algo.getscl = savage4_gpio_getscl;
203                 break;
204         default:
205                 par->chan.par = NULL;
206         }
207 
208         savage_setup_i2c_bus(&par->chan, "SAVAGE DDC2");
209 }
210 EXPORT_SYMBOL(savagefb_create_i2c_busses);
211 
212 void savagefb_delete_i2c_busses(struct fb_info *info)
213 {
214         struct savagefb_par *par = (struct savagefb_par *)info->par;
215         int (*del_bus)(struct i2c_adapter *) =
216                 symbol_get(i2c_bit_del_bus);
217 
218         if (del_bus && par->chan.par) {
219                 del_bus(&par->chan.adapter);
220                 symbol_put(i2c_bit_del_bus);
221         }
222 
223         par->chan.par = NULL;
224 }
225 EXPORT_SYMBOL(savagefb_delete_i2c_busses);
226 
227 static u8 *savage_do_probe_i2c_edid(struct savagefb_i2c_chan *chan)
228 {
229         u8 start = 0x0;
230         int (*transfer)(struct i2c_adapter *, struct i2c_msg *, int) =
231                 symbol_get(i2c_transfer);
232         struct i2c_msg msgs[] = {
233                 {
234                         .addr   = SAVAGE_DDC,
235                         .len    = 1,
236                         .buf    = &start,
237                 }, {
238                         .addr   = SAVAGE_DDC,
239                         .flags  = I2C_M_RD,
240                         .len    = EDID_LENGTH,
241                 },
242         };
243         u8 *buf = NULL;
244 
245         if (transfer && chan->par) {
246                 buf = kmalloc(EDID_LENGTH, GFP_KERNEL);
247 
248                 if (buf) {
249                         msgs[1].buf = buf;
250 
251                         if (transfer(&chan->adapter, msgs, 2) != 2) {
252                                 dev_dbg(&chan->par->pcidev->dev,
253                                         "Unable to read EDID block.\n");
254                                 kfree(buf);
255                                 buf = NULL;
256                         }
257                 }
258 
259                 symbol_put(i2c_transfer);
260         }
261 
262         return buf;
263 }
264 
265 int savagefb_probe_i2c_connector(struct savagefb_par *par, u8 **out_edid)
266 {
267         u8 *edid = NULL;
268         int i;
269 
270         for (i = 0; i < 3; i++) {
271                 /* Do the real work */
272                 edid = savage_do_probe_i2c_edid(&par->chan);
273                 if (edid)
274                         break;
275         }
276         if (out_edid)
277                 *out_edid = edid;
278         if (!edid)
279                 return 1;
280 
281         return 0;
282 }
283 EXPORT_SYMBOL(savagefb_probe_i2c_connector);
284 
285 MODULE_LICENSE("GPL");
286 
  This page was automatically generated by the LXR engine.