1/*
2 * Copyright © 2006 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Eric Anholt <eric@anholt.net>
25 * Thomas Richter <thor@math.tu-berlin.de>
26 *
27 * Minor modifications (Dithering enable):
28 * Thomas Richter <thor@math.tu-berlin.de>
29 *
30 */
31
32#include "intel_display_types.h"
33#include "intel_dvo_dev.h"
34
35/*
36 * register definitions for the i82807aa.
37 *
38 * Documentation on this chipset can be found in datasheet #29069001 at
39 * intel.com.
40 */
41
42/*
43 * VCH Revision & GMBus Base Addr
44 */
45#define VR00 0x00
46# define VR00_BASE_ADDRESS_MASK 0x007f
47
48/*
49 * Functionality Enable
50 */
51#define VR01 0x01
52
53/*
54 * Enable the panel fitter
55 */
56# define VR01_PANEL_FIT_ENABLE (1 << 3)
57/*
58 * Enables the LCD display.
59 *
60 * This must not be set while VR01_DVO_BYPASS_ENABLE is set.
61 */
62# define VR01_LCD_ENABLE (1 << 2)
63/* Enables the DVO repeater. */
64# define VR01_DVO_BYPASS_ENABLE (1 << 1)
65/* Enables the DVO clock */
66# define VR01_DVO_ENABLE (1 << 0)
67/* Enable dithering for 18bpp panels. Not documented. */
68# define VR01_DITHER_ENABLE (1 << 4)
69
70/*
71 * LCD Interface Format
72 */
73#define VR10 0x10
74/* Enables LVDS output instead of CMOS */
75# define VR10_LVDS_ENABLE (1 << 4)
76/* Enables 18-bit LVDS output. */
77# define VR10_INTERFACE_1X18 (0 << 2)
78/* Enables 24-bit LVDS or CMOS output */
79# define VR10_INTERFACE_1X24 (1 << 2)
80/* Enables 2x18-bit LVDS or CMOS output. */
81# define VR10_INTERFACE_2X18 (2 << 2)
82/* Enables 2x24-bit LVDS output */
83# define VR10_INTERFACE_2X24 (3 << 2)
84/* Mask that defines the depth of the pipeline */
85# define VR10_INTERFACE_DEPTH_MASK (3 << 2)
86
87/*
88 * VR20 LCD Horizontal Display Size
89 */
90#define VR20 0x20
91
92/*
93 * LCD Vertical Display Size
94 */
95#define VR21 0x21
96
97/*
98 * Panel power down status
99 */
100#define VR30 0x30
101/* Read only bit indicating that the panel is not in a safe poweroff state. */
102# define VR30_PANEL_ON (1 << 15)
103
104#define VR40 0x40
105# define VR40_STALL_ENABLE (1 << 13)
106# define VR40_VERTICAL_INTERP_ENABLE (1 << 12)
107# define VR40_ENHANCED_PANEL_FITTING (1 << 11)
108# define VR40_HORIZONTAL_INTERP_ENABLE (1 << 10)
109# define VR40_AUTO_RATIO_ENABLE (1 << 9)
110# define VR40_CLOCK_GATING_ENABLE (1 << 8)
111
112/*
113 * Panel Fitting Vertical Ratio
114 * (((image_height - 1) << 16) / ((panel_height - 1))) >> 2
115 */
116#define VR41 0x41
117
118/*
119 * Panel Fitting Horizontal Ratio
120 * (((image_width - 1) << 16) / ((panel_width - 1))) >> 2
121 */
122#define VR42 0x42
123
124/*
125 * Horizontal Image Size
126 */
127#define VR43 0x43
128
129/* VR80 GPIO 0
130 */
131#define VR80 0x80
132#define VR81 0x81
133#define VR82 0x82
134#define VR83 0x83
135#define VR84 0x84
136#define VR85 0x85
137#define VR86 0x86
138#define VR87 0x87
139
140/* VR88 GPIO 8
141 */
142#define VR88 0x88
143
144/* Graphics BIOS scratch 0
145 */
146#define VR8E 0x8E
147# define VR8E_PANEL_TYPE_MASK (0xf << 0)
148# define VR8E_PANEL_INTERFACE_CMOS (0 << 4)
149# define VR8E_PANEL_INTERFACE_LVDS (1 << 4)
150# define VR8E_FORCE_DEFAULT_PANEL (1 << 5)
151
152/* Graphics BIOS scratch 1
153 */
154#define VR8F 0x8F
155# define VR8F_VCH_PRESENT (1 << 0)
156# define VR8F_DISPLAY_CONN (1 << 1)
157# define VR8F_POWER_MASK (0x3c)
158# define VR8F_POWER_POS (2)
159
160/* Some Bios implementations do not restore the DVO state upon
161 * resume from standby. Thus, this driver has to handle it
162 * instead. The following list contains all registers that
163 * require saving.
164 */
165static const u16 backup_addresses[] = {
166 0x11, 0x12,
167 0x18, 0x19, 0x1a, 0x1f,
168 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
169 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
170 0x8e, 0x8f,
171 0x10 /* this must come last */
172};
173
174
175struct ivch_priv {
176 bool quiet;
177
178 u16 width, height;
179
180 /* Register backup */
181
182 u16 reg_backup[ARRAY_SIZE(backup_addresses)];
183};
184
185
186static void ivch_dump_regs(struct intel_dvo_device *dvo);
187/*
188 * Reads a register on the ivch.
189 *
190 * Each of the 256 registers are 16 bits long.
191 */
192static bool ivch_read(struct intel_dvo_device *dvo, int addr, u16 *data)
193{
194 struct ivch_priv *priv = dvo->dev_priv;
195 struct i2c_adapter *adapter = dvo->i2c_bus;
196 u8 out_buf[1];
197 u8 in_buf[2];
198
199 struct i2c_msg msgs[] = {
200 {
201 .addr = dvo->slave_addr,
202 .flags = I2C_M_RD,
203 .len = 0,
204 },
205 {
206 .addr = 0,
207 .flags = I2C_M_NOSTART,
208 .len = 1,
209 .buf = out_buf,
210 },
211 {
212 .addr = dvo->slave_addr,
213 .flags = I2C_M_RD | I2C_M_NOSTART,
214 .len = 2,
215 .buf = in_buf,
216 }
217 };
218
219 out_buf[0] = addr;
220
221 if (i2c_transfer(adap: adapter, msgs, num: 3) == 3) {
222 *data = (in_buf[1] << 8) | in_buf[0];
223 return true;
224 }
225
226 if (!priv->quiet) {
227 DRM_DEBUG_KMS("Unable to read register 0x%02x from "
228 "%s:%02x.\n",
229 addr, adapter->name, dvo->slave_addr);
230 }
231 return false;
232}
233
234/* Writes a 16-bit register on the ivch */
235static bool ivch_write(struct intel_dvo_device *dvo, int addr, u16 data)
236{
237 struct ivch_priv *priv = dvo->dev_priv;
238 struct i2c_adapter *adapter = dvo->i2c_bus;
239 u8 out_buf[3];
240 struct i2c_msg msg = {
241 .addr = dvo->slave_addr,
242 .flags = 0,
243 .len = 3,
244 .buf = out_buf,
245 };
246
247 out_buf[0] = addr;
248 out_buf[1] = data & 0xff;
249 out_buf[2] = data >> 8;
250
251 if (i2c_transfer(adap: adapter, msgs: &msg, num: 1) == 1)
252 return true;
253
254 if (!priv->quiet) {
255 DRM_DEBUG_KMS("Unable to write register 0x%02x to %s:%d.\n",
256 addr, adapter->name, dvo->slave_addr);
257 }
258
259 return false;
260}
261
262/* Probes the given bus and slave address for an ivch */
263static bool ivch_init(struct intel_dvo_device *dvo,
264 struct i2c_adapter *adapter)
265{
266 struct ivch_priv *priv;
267 u16 temp;
268 int i;
269
270 priv = kzalloc(size: sizeof(*priv), GFP_KERNEL);
271 if (priv == NULL)
272 return false;
273
274 dvo->i2c_bus = adapter;
275 dvo->dev_priv = priv;
276 priv->quiet = true;
277
278 if (!ivch_read(dvo, VR00, data: &temp))
279 goto out;
280 priv->quiet = false;
281
282 /* Since the identification bits are probably zeroes, which doesn't seem
283 * very unique, check that the value in the base address field matches
284 * the address it's responding on.
285 */
286 if ((temp & VR00_BASE_ADDRESS_MASK) != dvo->slave_addr) {
287 DRM_DEBUG_KMS("ivch detect failed due to address mismatch "
288 "(%d vs %d)\n",
289 (temp & VR00_BASE_ADDRESS_MASK), dvo->slave_addr);
290 goto out;
291 }
292
293 ivch_read(dvo, VR20, data: &priv->width);
294 ivch_read(dvo, VR21, data: &priv->height);
295
296 /* Make a backup of the registers to be able to restore them
297 * upon suspend.
298 */
299 for (i = 0; i < ARRAY_SIZE(backup_addresses); i++)
300 ivch_read(dvo, addr: backup_addresses[i], data: priv->reg_backup + i);
301
302 ivch_dump_regs(dvo);
303
304 return true;
305
306out:
307 kfree(objp: priv);
308 return false;
309}
310
311static enum drm_connector_status ivch_detect(struct intel_dvo_device *dvo)
312{
313 return connector_status_connected;
314}
315
316static enum drm_mode_status ivch_mode_valid(struct intel_dvo_device *dvo,
317 struct drm_display_mode *mode)
318{
319 if (mode->clock > 112000)
320 return MODE_CLOCK_HIGH;
321
322 return MODE_OK;
323}
324
325/* Restore the DVO registers after a resume
326 * from RAM. Registers have been saved during
327 * the initialization.
328 */
329static void ivch_reset(struct intel_dvo_device *dvo)
330{
331 struct ivch_priv *priv = dvo->dev_priv;
332 int i;
333
334 DRM_DEBUG_KMS("Resetting the IVCH registers\n");
335
336 ivch_write(dvo, VR10, data: 0x0000);
337
338 for (i = 0; i < ARRAY_SIZE(backup_addresses); i++)
339 ivch_write(dvo, addr: backup_addresses[i], data: priv->reg_backup[i]);
340}
341
342/* Sets the power state of the panel connected to the ivch */
343static void ivch_dpms(struct intel_dvo_device *dvo, bool enable)
344{
345 int i;
346 u16 vr01, vr30, backlight;
347
348 ivch_reset(dvo);
349
350 /* Set the new power state of the panel. */
351 if (!ivch_read(dvo, VR01, data: &vr01))
352 return;
353
354 if (enable)
355 backlight = 1;
356 else
357 backlight = 0;
358
359 ivch_write(dvo, VR80, data: backlight);
360
361 if (enable)
362 vr01 |= VR01_LCD_ENABLE | VR01_DVO_ENABLE;
363 else
364 vr01 &= ~(VR01_LCD_ENABLE | VR01_DVO_ENABLE);
365
366 ivch_write(dvo, VR01, data: vr01);
367
368 /* Wait for the panel to make its state transition */
369 for (i = 0; i < 100; i++) {
370 if (!ivch_read(dvo, VR30, data: &vr30))
371 break;
372
373 if (((vr30 & VR30_PANEL_ON) != 0) == enable)
374 break;
375 udelay(1000);
376 }
377 /* wait some more; vch may fail to resync sometimes without this */
378 udelay(16 * 1000);
379}
380
381static bool ivch_get_hw_state(struct intel_dvo_device *dvo)
382{
383 u16 vr01;
384
385 ivch_reset(dvo);
386
387 /* Set the new power state of the panel. */
388 if (!ivch_read(dvo, VR01, data: &vr01))
389 return false;
390
391 if (vr01 & VR01_LCD_ENABLE)
392 return true;
393 else
394 return false;
395}
396
397static void ivch_mode_set(struct intel_dvo_device *dvo,
398 const struct drm_display_mode *mode,
399 const struct drm_display_mode *adjusted_mode)
400{
401 struct ivch_priv *priv = dvo->dev_priv;
402 u16 vr40 = 0;
403 u16 vr01 = 0;
404 u16 vr10;
405
406 ivch_reset(dvo);
407
408 vr10 = priv->reg_backup[ARRAY_SIZE(backup_addresses) - 1];
409
410 /* Enable dithering for 18 bpp pipelines */
411 vr10 &= VR10_INTERFACE_DEPTH_MASK;
412 if (vr10 == VR10_INTERFACE_2X18 || vr10 == VR10_INTERFACE_1X18)
413 vr01 = VR01_DITHER_ENABLE;
414
415 vr40 = (VR40_STALL_ENABLE | VR40_VERTICAL_INTERP_ENABLE |
416 VR40_HORIZONTAL_INTERP_ENABLE);
417
418 if (mode->hdisplay != adjusted_mode->crtc_hdisplay ||
419 mode->vdisplay != adjusted_mode->crtc_vdisplay) {
420 u16 x_ratio, y_ratio;
421
422 vr01 |= VR01_PANEL_FIT_ENABLE;
423 vr40 |= VR40_CLOCK_GATING_ENABLE;
424 x_ratio = (((mode->hdisplay - 1) << 16) /
425 (adjusted_mode->crtc_hdisplay - 1)) >> 2;
426 y_ratio = (((mode->vdisplay - 1) << 16) /
427 (adjusted_mode->crtc_vdisplay - 1)) >> 2;
428 ivch_write(dvo, VR42, data: x_ratio);
429 ivch_write(dvo, VR41, data: y_ratio);
430 } else {
431 vr01 &= ~VR01_PANEL_FIT_ENABLE;
432 vr40 &= ~VR40_CLOCK_GATING_ENABLE;
433 }
434 vr40 &= ~VR40_AUTO_RATIO_ENABLE;
435
436 ivch_write(dvo, VR01, data: vr01);
437 ivch_write(dvo, VR40, data: vr40);
438}
439
440static void ivch_dump_regs(struct intel_dvo_device *dvo)
441{
442 u16 val;
443
444 ivch_read(dvo, VR00, data: &val);
445 DRM_DEBUG_KMS("VR00: 0x%04x\n", val);
446 ivch_read(dvo, VR01, data: &val);
447 DRM_DEBUG_KMS("VR01: 0x%04x\n", val);
448 ivch_read(dvo, VR10, data: &val);
449 DRM_DEBUG_KMS("VR10: 0x%04x\n", val);
450 ivch_read(dvo, VR30, data: &val);
451 DRM_DEBUG_KMS("VR30: 0x%04x\n", val);
452 ivch_read(dvo, VR40, data: &val);
453 DRM_DEBUG_KMS("VR40: 0x%04x\n", val);
454
455 /* GPIO registers */
456 ivch_read(dvo, VR80, data: &val);
457 DRM_DEBUG_KMS("VR80: 0x%04x\n", val);
458 ivch_read(dvo, VR81, data: &val);
459 DRM_DEBUG_KMS("VR81: 0x%04x\n", val);
460 ivch_read(dvo, VR82, data: &val);
461 DRM_DEBUG_KMS("VR82: 0x%04x\n", val);
462 ivch_read(dvo, VR83, data: &val);
463 DRM_DEBUG_KMS("VR83: 0x%04x\n", val);
464 ivch_read(dvo, VR84, data: &val);
465 DRM_DEBUG_KMS("VR84: 0x%04x\n", val);
466 ivch_read(dvo, VR85, data: &val);
467 DRM_DEBUG_KMS("VR85: 0x%04x\n", val);
468 ivch_read(dvo, VR86, data: &val);
469 DRM_DEBUG_KMS("VR86: 0x%04x\n", val);
470 ivch_read(dvo, VR87, data: &val);
471 DRM_DEBUG_KMS("VR87: 0x%04x\n", val);
472 ivch_read(dvo, VR88, data: &val);
473 DRM_DEBUG_KMS("VR88: 0x%04x\n", val);
474
475 /* Scratch register 0 - AIM Panel type */
476 ivch_read(dvo, VR8E, data: &val);
477 DRM_DEBUG_KMS("VR8E: 0x%04x\n", val);
478
479 /* Scratch register 1 - Status register */
480 ivch_read(dvo, VR8F, data: &val);
481 DRM_DEBUG_KMS("VR8F: 0x%04x\n", val);
482}
483
484static void ivch_destroy(struct intel_dvo_device *dvo)
485{
486 struct ivch_priv *priv = dvo->dev_priv;
487
488 if (priv) {
489 kfree(objp: priv);
490 dvo->dev_priv = NULL;
491 }
492}
493
494const struct intel_dvo_dev_ops ivch_ops = {
495 .init = ivch_init,
496 .dpms = ivch_dpms,
497 .get_hw_state = ivch_get_hw_state,
498 .mode_valid = ivch_mode_valid,
499 .mode_set = ivch_mode_set,
500 .detect = ivch_detect,
501 .dump_regs = ivch_dump_regs,
502 .destroy = ivch_destroy,
503};
504

source code of linux/drivers/gpu/drm/i915/display/dvo_ivch.c