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 "dvo.h"
33
34/*
35 * register definitions for the i82807aa.
36 *
37 * Documentation on this chipset can be found in datasheet #29069001 at
38 * intel.com.
39 */
40
41/*
42 * VCH Revision & GMBus Base Addr
43 */
44#define VR00		0x00
45# define VR00_BASE_ADDRESS_MASK		0x007f
46
47/*
48 * Functionality Enable
49 */
50#define VR01		0x01
51
52/*
53 * Enable the panel fitter
54 */
55# define VR01_PANEL_FIT_ENABLE		(1 << 3)
56/*
57 * Enables the LCD display.
58 *
59 * This must not be set while VR01_DVO_BYPASS_ENABLE is set.
60 */
61# define VR01_LCD_ENABLE		(1 << 2)
62/** Enables the DVO repeater. */
63# define VR01_DVO_BYPASS_ENABLE		(1 << 1)
64/** Enables the DVO clock */
65# define VR01_DVO_ENABLE		(1 << 0)
66/** Enable dithering for 18bpp panels. Not documented. */
67# define VR01_DITHER_ENABLE             (1 << 4)
68
69/*
70 * LCD Interface Format
71 */
72#define VR10		0x10
73/** Enables LVDS output instead of CMOS */
74# define VR10_LVDS_ENABLE		(1 << 4)
75/** Enables 18-bit LVDS output. */
76# define VR10_INTERFACE_1X18		(0 << 2)
77/** Enables 24-bit LVDS or CMOS output */
78# define VR10_INTERFACE_1X24		(1 << 2)
79/** Enables 2x18-bit LVDS or CMOS output. */
80# define VR10_INTERFACE_2X18		(2 << 2)
81/** Enables 2x24-bit LVDS output */
82# define VR10_INTERFACE_2X24		(3 << 2)
83/** Mask that defines the depth of the pipeline */
84# define VR10_INTERFACE_DEPTH_MASK      (3 << 2)
85
86/*
87 * VR20 LCD Horizontal Display Size
88 */
89#define VR20	0x20
90
91/*
92 * LCD Vertical Display Size
93 */
94#define VR21	0x21
95
96/*
97 * Panel power down status
98 */
99#define VR30		0x30
100/** Read only bit indicating that the panel is not in a safe poweroff state. */
101# define VR30_PANEL_ON			(1 << 15)
102
103#define VR40		0x40
104# define VR40_STALL_ENABLE		(1 << 13)
105# define VR40_VERTICAL_INTERP_ENABLE	(1 << 12)
106# define VR40_ENHANCED_PANEL_FITTING	(1 << 11)
107# define VR40_HORIZONTAL_INTERP_ENABLE	(1 << 10)
108# define VR40_AUTO_RATIO_ENABLE		(1 << 9)
109# define VR40_CLOCK_GATING_ENABLE	(1 << 8)
110
111/*
112 * Panel Fitting Vertical Ratio
113 * (((image_height - 1) << 16) / ((panel_height - 1))) >> 2
114 */
115#define VR41		0x41
116
117/*
118 * Panel Fitting Horizontal Ratio
119 * (((image_width - 1) << 16) / ((panel_width - 1))) >> 2
120 */
121#define VR42		0x42
122
123/*
124 * Horizontal Image Size
125 */
126#define VR43		0x43
127
128/* VR80 GPIO 0
129 */
130#define VR80	    0x80
131#define VR81	    0x81
132#define VR82	    0x82
133#define VR83	    0x83
134#define VR84	    0x84
135#define VR85	    0x85
136#define VR86	    0x86
137#define VR87	    0x87
138
139/* VR88 GPIO 8
140 */
141#define VR88	    0x88
142
143/* Graphics BIOS scratch 0
144 */
145#define VR8E	    0x8E
146# define VR8E_PANEL_TYPE_MASK		(0xf << 0)
147# define VR8E_PANEL_INTERFACE_CMOS	(0 << 4)
148# define VR8E_PANEL_INTERFACE_LVDS	(1 << 4)
149# define VR8E_FORCE_DEFAULT_PANEL	(1 << 5)
150
151/* Graphics BIOS scratch 1
152 */
153#define VR8F	    0x8F
154# define VR8F_VCH_PRESENT		(1 << 0)
155# define VR8F_DISPLAY_CONN		(1 << 1)
156# define VR8F_POWER_MASK		(0x3c)
157# define VR8F_POWER_POS			(2)
158
159/* Some Bios implementations do not restore the DVO state upon
160 * resume from standby. Thus, this driver has to handle it
161 * instead. The following list contains all registers that
162 * require saving.
163 */
164static const uint16_t backup_addresses[] = {
165	0x11, 0x12,
166	0x18, 0x19, 0x1a, 0x1f,
167	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
168	0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
169	0x8e, 0x8f,
170	0x10		/* this must come last */
171};
172
173
174struct ivch_priv {
175	bool quiet;
176
177	uint16_t width, height;
178
179	/* Register backup */
180
181	uint16_t reg_backup[ARRAY_SIZE(backup_addresses)];
182};
183
184
185static void ivch_dump_regs(struct intel_dvo_device *dvo);
186/**
187 * Reads a register on the ivch.
188 *
189 * Each of the 256 registers are 16 bits long.
190 */
191static bool ivch_read(struct intel_dvo_device *dvo, int addr, uint16_t *data)
192{
193	struct ivch_priv *priv = dvo->dev_priv;
194	struct i2c_adapter *adapter = dvo->i2c_bus;
195	u8 out_buf[1];
196	u8 in_buf[2];
197
198	struct i2c_msg msgs[] = {
199		{
200			.addr = dvo->slave_addr,
201			.flags = I2C_M_RD,
202			.len = 0,
203		},
204		{
205			.addr = 0,
206			.flags = I2C_M_NOSTART,
207			.len = 1,
208			.buf = out_buf,
209		},
210		{
211			.addr = dvo->slave_addr,
212			.flags = I2C_M_RD | I2C_M_NOSTART,
213			.len = 2,
214			.buf = in_buf,
215		}
216	};
217
218	out_buf[0] = addr;
219
220	if (i2c_transfer(adapter, msgs, 3) == 3) {
221		*data = (in_buf[1] << 8) | in_buf[0];
222		return true;
223	}
224
225	if (!priv->quiet) {
226		DRM_DEBUG_KMS("Unable to read register 0x%02x from "
227				"%s:%02x.\n",
228			  addr, adapter->name, dvo->slave_addr);
229	}
230	return false;
231}
232
233/** Writes a 16-bit register on the ivch */
234static bool ivch_write(struct intel_dvo_device *dvo, int addr, uint16_t data)
235{
236	struct ivch_priv *priv = dvo->dev_priv;
237	struct i2c_adapter *adapter = dvo->i2c_bus;
238	u8 out_buf[3];
239	struct i2c_msg msg = {
240		.addr = dvo->slave_addr,
241		.flags = 0,
242		.len = 3,
243		.buf = out_buf,
244	};
245
246	out_buf[0] = addr;
247	out_buf[1] = data & 0xff;
248	out_buf[2] = data >> 8;
249
250	if (i2c_transfer(adapter, &msg, 1) == 1)
251		return true;
252
253	if (!priv->quiet) {
254		DRM_DEBUG_KMS("Unable to write register 0x%02x to %s:%d.\n",
255			  addr, adapter->name, dvo->slave_addr);
256	}
257
258	return false;
259}
260
261/** Probes the given bus and slave address for an ivch */
262static bool ivch_init(struct intel_dvo_device *dvo,
263		      struct i2c_adapter *adapter)
264{
265	struct ivch_priv *priv;
266	uint16_t temp;
267	int i;
268
269	priv = kzalloc(sizeof(struct ivch_priv), GFP_KERNEL);
270	if (priv == NULL)
271		return false;
272
273	dvo->i2c_bus = adapter;
274	dvo->dev_priv = priv;
275	priv->quiet = true;
276
277	if (!ivch_read(dvo, VR00, &temp))
278		goto out;
279	priv->quiet = false;
280
281	/* Since the identification bits are probably zeroes, which doesn't seem
282	 * very unique, check that the value in the base address field matches
283	 * the address it's responding on.
284	 */
285	if ((temp & VR00_BASE_ADDRESS_MASK) != dvo->slave_addr) {
286		DRM_DEBUG_KMS("ivch detect failed due to address mismatch "
287			  "(%d vs %d)\n",
288			  (temp & VR00_BASE_ADDRESS_MASK), dvo->slave_addr);
289		goto out;
290	}
291
292	ivch_read(dvo, VR20, &priv->width);
293	ivch_read(dvo, VR21, &priv->height);
294
295	/* Make a backup of the registers to be able to restore them
296	 * upon suspend.
297	 */
298	for (i = 0; i < ARRAY_SIZE(backup_addresses); i++)
299		ivch_read(dvo, backup_addresses[i], priv->reg_backup + i);
300
301	ivch_dump_regs(dvo);
302
303	return true;
304
305out:
306	kfree(priv);
307	return false;
308}
309
310static enum drm_connector_status ivch_detect(struct intel_dvo_device *dvo)
311{
312	return connector_status_connected;
313}
314
315static enum drm_mode_status ivch_mode_valid(struct intel_dvo_device *dvo,
316					    struct drm_display_mode *mode)
317{
318	if (mode->clock > 112000)
319		return MODE_CLOCK_HIGH;
320
321	return MODE_OK;
322}
323
324/* Restore the DVO registers after a resume
325 * from RAM. Registers have been saved during
326 * the initialization.
327 */
328static void ivch_reset(struct intel_dvo_device *dvo)
329{
330	struct ivch_priv *priv = dvo->dev_priv;
331	int i;
332
333	DRM_DEBUG_KMS("Resetting the IVCH registers\n");
334
335	ivch_write(dvo, VR10, 0x0000);
336
337	for (i = 0; i < ARRAY_SIZE(backup_addresses); i++)
338		ivch_write(dvo, backup_addresses[i], priv->reg_backup[i]);
339}
340
341/** Sets the power state of the panel connected to the ivch */
342static void ivch_dpms(struct intel_dvo_device *dvo, bool enable)
343{
344	int i;
345	uint16_t vr01, vr30, backlight;
346
347	ivch_reset(dvo);
348
349	/* Set the new power state of the panel. */
350	if (!ivch_read(dvo, VR01, &vr01))
351		return;
352
353	if (enable)
354		backlight = 1;
355	else
356		backlight = 0;
357
358	ivch_write(dvo, VR80, backlight);
359
360	if (enable)
361		vr01 |= VR01_LCD_ENABLE | VR01_DVO_ENABLE;
362	else
363		vr01 &= ~(VR01_LCD_ENABLE | VR01_DVO_ENABLE);
364
365	ivch_write(dvo, VR01, vr01);
366
367	/* Wait for the panel to make its state transition */
368	for (i = 0; i < 100; i++) {
369		if (!ivch_read(dvo, VR30, &vr30))
370			break;
371
372		if (((vr30 & VR30_PANEL_ON) != 0) == enable)
373			break;
374		udelay(1000);
375	}
376	/* wait some more; vch may fail to resync sometimes without this */
377	udelay(16 * 1000);
378}
379
380static bool ivch_get_hw_state(struct intel_dvo_device *dvo)
381{
382	uint16_t vr01;
383
384	ivch_reset(dvo);
385
386	/* Set the new power state of the panel. */
387	if (!ivch_read(dvo, VR01, &vr01))
388		return false;
389
390	if (vr01 & VR01_LCD_ENABLE)
391		return true;
392	else
393		return false;
394}
395
396static void ivch_mode_set(struct intel_dvo_device *dvo,
397			  const struct drm_display_mode *mode,
398			  const struct drm_display_mode *adjusted_mode)
399{
400	struct ivch_priv *priv = dvo->dev_priv;
401	uint16_t vr40 = 0;
402	uint16_t vr01 = 0;
403	uint16_t vr10;
404
405	ivch_reset(dvo);
406
407	vr10 = priv->reg_backup[ARRAY_SIZE(backup_addresses) - 1];
408
409	/* Enable dithering for 18 bpp pipelines */
410	vr10 &= VR10_INTERFACE_DEPTH_MASK;
411	if (vr10 == VR10_INTERFACE_2X18 || vr10 == VR10_INTERFACE_1X18)
412		vr01 = VR01_DITHER_ENABLE;
413
414	vr40 = (VR40_STALL_ENABLE | VR40_VERTICAL_INTERP_ENABLE |
415		VR40_HORIZONTAL_INTERP_ENABLE);
416
417	if (mode->hdisplay != adjusted_mode->crtc_hdisplay ||
418	    mode->vdisplay != adjusted_mode->crtc_vdisplay) {
419		uint16_t x_ratio, y_ratio;
420
421		vr01 |= VR01_PANEL_FIT_ENABLE;
422		vr40 |= VR40_CLOCK_GATING_ENABLE;
423		x_ratio = (((mode->hdisplay - 1) << 16) /
424			   (adjusted_mode->crtc_hdisplay - 1)) >> 2;
425		y_ratio = (((mode->vdisplay - 1) << 16) /
426			   (adjusted_mode->crtc_vdisplay - 1)) >> 2;
427		ivch_write(dvo, VR42, x_ratio);
428		ivch_write(dvo, VR41, y_ratio);
429	} else {
430		vr01 &= ~VR01_PANEL_FIT_ENABLE;
431		vr40 &= ~VR40_CLOCK_GATING_ENABLE;
432	}
433	vr40 &= ~VR40_AUTO_RATIO_ENABLE;
434
435	ivch_write(dvo, VR01, vr01);
436	ivch_write(dvo, VR40, vr40);
437}
438
439static void ivch_dump_regs(struct intel_dvo_device *dvo)
440{
441	uint16_t val;
442
443	ivch_read(dvo, VR00, &val);
444	DRM_DEBUG_KMS("VR00: 0x%04x\n", val);
445	ivch_read(dvo, VR01, &val);
446	DRM_DEBUG_KMS("VR01: 0x%04x\n", val);
447	ivch_read(dvo, VR10, &val);
448	DRM_DEBUG_KMS("VR10: 0x%04x\n", val);
449	ivch_read(dvo, VR30, &val);
450	DRM_DEBUG_KMS("VR30: 0x%04x\n", val);
451	ivch_read(dvo, VR40, &val);
452	DRM_DEBUG_KMS("VR40: 0x%04x\n", val);
453
454	/* GPIO registers */
455	ivch_read(dvo, VR80, &val);
456	DRM_DEBUG_KMS("VR80: 0x%04x\n", val);
457	ivch_read(dvo, VR81, &val);
458	DRM_DEBUG_KMS("VR81: 0x%04x\n", val);
459	ivch_read(dvo, VR82, &val);
460	DRM_DEBUG_KMS("VR82: 0x%04x\n", val);
461	ivch_read(dvo, VR83, &val);
462	DRM_DEBUG_KMS("VR83: 0x%04x\n", val);
463	ivch_read(dvo, VR84, &val);
464	DRM_DEBUG_KMS("VR84: 0x%04x\n", val);
465	ivch_read(dvo, VR85, &val);
466	DRM_DEBUG_KMS("VR85: 0x%04x\n", val);
467	ivch_read(dvo, VR86, &val);
468	DRM_DEBUG_KMS("VR86: 0x%04x\n", val);
469	ivch_read(dvo, VR87, &val);
470	DRM_DEBUG_KMS("VR87: 0x%04x\n", val);
471	ivch_read(dvo, VR88, &val);
472	DRM_DEBUG_KMS("VR88: 0x%04x\n", val);
473
474	/* Scratch register 0 - AIM Panel type */
475	ivch_read(dvo, VR8E, &val);
476	DRM_DEBUG_KMS("VR8E: 0x%04x\n", val);
477
478	/* Scratch register 1 - Status register */
479	ivch_read(dvo, VR8F, &val);
480	DRM_DEBUG_KMS("VR8F: 0x%04x\n", val);
481}
482
483static void ivch_destroy(struct intel_dvo_device *dvo)
484{
485	struct ivch_priv *priv = dvo->dev_priv;
486
487	if (priv) {
488		kfree(priv);
489		dvo->dev_priv = NULL;
490	}
491}
492
493struct intel_dvo_dev_ops ivch_ops = {
494	.init = ivch_init,
495	.dpms = ivch_dpms,
496	.get_hw_state = ivch_get_hw_state,
497	.mode_valid = ivch_mode_valid,
498	.mode_set = ivch_mode_set,
499	.detect = ivch_detect,
500	.dump_regs = ivch_dump_regs,
501	.destroy = ivch_destroy,
502};
503