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(adapter, msgs, 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(adapter, &msg, 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(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, &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, &priv->width);
294	ivch_read(dvo, VR21, &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, backup_addresses[i], priv->reg_backup + i);
301
302	ivch_dump_regs(dvo);
303
304	return true;
305
306out:
307	kfree(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, 0x0000);
337
338	for (i = 0; i < ARRAY_SIZE(backup_addresses); i++)
339		ivch_write(dvo, backup_addresses[i], 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, &vr01))
352		return;
353
354	if (enable)
355		backlight = 1;
356	else
357		backlight = 0;
358
359	ivch_write(dvo, VR80, 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, 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, &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, &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, x_ratio);
429		ivch_write(dvo, VR41, 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, vr01);
437	ivch_write(dvo, VR40, vr40);
438}
439
440static void ivch_dump_regs(struct intel_dvo_device *dvo)
441{
442	u16 val;
443
444	ivch_read(dvo, VR00, &val);
445	DRM_DEBUG_KMS("VR00: 0x%04x\n", val);
446	ivch_read(dvo, VR01, &val);
447	DRM_DEBUG_KMS("VR01: 0x%04x\n", val);
448	ivch_read(dvo, VR10, &val);
449	DRM_DEBUG_KMS("VR10: 0x%04x\n", val);
450	ivch_read(dvo, VR30, &val);
451	DRM_DEBUG_KMS("VR30: 0x%04x\n", val);
452	ivch_read(dvo, VR40, &val);
453	DRM_DEBUG_KMS("VR40: 0x%04x\n", val);
454
455	/* GPIO registers */
456	ivch_read(dvo, VR80, &val);
457	DRM_DEBUG_KMS("VR80: 0x%04x\n", val);
458	ivch_read(dvo, VR81, &val);
459	DRM_DEBUG_KMS("VR81: 0x%04x\n", val);
460	ivch_read(dvo, VR82, &val);
461	DRM_DEBUG_KMS("VR82: 0x%04x\n", val);
462	ivch_read(dvo, VR83, &val);
463	DRM_DEBUG_KMS("VR83: 0x%04x\n", val);
464	ivch_read(dvo, VR84, &val);
465	DRM_DEBUG_KMS("VR84: 0x%04x\n", val);
466	ivch_read(dvo, VR85, &val);
467	DRM_DEBUG_KMS("VR85: 0x%04x\n", val);
468	ivch_read(dvo, VR86, &val);
469	DRM_DEBUG_KMS("VR86: 0x%04x\n", val);
470	ivch_read(dvo, VR87, &val);
471	DRM_DEBUG_KMS("VR87: 0x%04x\n", val);
472	ivch_read(dvo, VR88, &val);
473	DRM_DEBUG_KMS("VR88: 0x%04x\n", val);
474
475	/* Scratch register 0 - AIM Panel type */
476	ivch_read(dvo, VR8E, &val);
477	DRM_DEBUG_KMS("VR8E: 0x%04x\n", val);
478
479	/* Scratch register 1 - Status register */
480	ivch_read(dvo, VR8F, &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(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