1/*
2 * Copyright (C) 2010 Francisco Jerez.
3 * All Rights Reserved.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the
14 * next paragraph) shall be included in all copies or substantial
15 * portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
20 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 *
25 */
26
27#include <linux/module.h>
28
29#include <drm/drm_drv.h>
30#include <drm/drm_encoder_slave.h>
31#include <drm/drm_print.h>
32#include <drm/drm_probe_helper.h>
33#include <drm/i2c/sil164.h>
34
35struct sil164_priv {
36	struct sil164_encoder_params config;
37	struct i2c_client *duallink_slave;
38
39	uint8_t saved_state[0x10];
40	uint8_t saved_slave_state[0x10];
41};
42
43#define to_sil164_priv(x) \
44	((struct sil164_priv *)to_encoder_slave(x)->slave_priv)
45
46#define sil164_dbg(client, format, ...) do {				\
47		if (drm_debug_enabled(DRM_UT_KMS))			\
48			dev_printk(KERN_DEBUG, &client->dev,		\
49				   "%s: " format, __func__, ## __VA_ARGS__); \
50	} while (0)
51#define sil164_info(client, format, ...)		\
52	dev_info(&client->dev, format, __VA_ARGS__)
53#define sil164_err(client, format, ...)			\
54	dev_err(&client->dev, format, __VA_ARGS__)
55
56#define SIL164_I2C_ADDR_MASTER			0x38
57#define SIL164_I2C_ADDR_SLAVE			0x39
58
59/* HW register definitions */
60
61#define SIL164_VENDOR_LO			0x0
62#define SIL164_VENDOR_HI			0x1
63#define SIL164_DEVICE_LO			0x2
64#define SIL164_DEVICE_HI			0x3
65#define SIL164_REVISION				0x4
66#define SIL164_FREQ_MIN				0x6
67#define SIL164_FREQ_MAX				0x7
68#define SIL164_CONTROL0				0x8
69#  define SIL164_CONTROL0_POWER_ON		0x01
70#  define SIL164_CONTROL0_EDGE_RISING		0x02
71#  define SIL164_CONTROL0_INPUT_24BIT		0x04
72#  define SIL164_CONTROL0_DUAL_EDGE		0x08
73#  define SIL164_CONTROL0_HSYNC_ON		0x10
74#  define SIL164_CONTROL0_VSYNC_ON		0x20
75#define SIL164_DETECT				0x9
76#  define SIL164_DETECT_INTR_STAT		0x01
77#  define SIL164_DETECT_HOTPLUG_STAT		0x02
78#  define SIL164_DETECT_RECEIVER_STAT		0x04
79#  define SIL164_DETECT_INTR_MODE_RECEIVER	0x00
80#  define SIL164_DETECT_INTR_MODE_HOTPLUG	0x08
81#  define SIL164_DETECT_OUT_MODE_HIGH		0x00
82#  define SIL164_DETECT_OUT_MODE_INTR		0x10
83#  define SIL164_DETECT_OUT_MODE_RECEIVER	0x20
84#  define SIL164_DETECT_OUT_MODE_HOTPLUG	0x30
85#  define SIL164_DETECT_VSWING_STAT		0x80
86#define SIL164_CONTROL1				0xa
87#  define SIL164_CONTROL1_DESKEW_ENABLE		0x10
88#  define SIL164_CONTROL1_DESKEW_INCR_SHIFT	5
89#define SIL164_GPIO				0xb
90#define SIL164_CONTROL2				0xc
91#  define SIL164_CONTROL2_FILTER_ENABLE		0x01
92#  define SIL164_CONTROL2_FILTER_SETTING_SHIFT	1
93#  define SIL164_CONTROL2_DUALLINK_MASTER	0x40
94#  define SIL164_CONTROL2_SYNC_CONT		0x80
95#define SIL164_DUALLINK				0xd
96#  define SIL164_DUALLINK_ENABLE		0x10
97#  define SIL164_DUALLINK_SKEW_SHIFT		5
98#define SIL164_PLLZONE				0xe
99#  define SIL164_PLLZONE_STAT			0x08
100#  define SIL164_PLLZONE_FORCE_ON		0x10
101#  define SIL164_PLLZONE_FORCE_HIGH		0x20
102
103/* HW access functions */
104
105static void
106sil164_write(struct i2c_client *client, uint8_t addr, uint8_t val)
107{
108	uint8_t buf[] = {addr, val};
109	int ret;
110
111	ret = i2c_master_send(client, buf, ARRAY_SIZE(buf));
112	if (ret < 0)
113		sil164_err(client, "Error %d writing to subaddress 0x%x\n",
114			   ret, addr);
115}
116
117static uint8_t
118sil164_read(struct i2c_client *client, uint8_t addr)
119{
120	uint8_t val;
121	int ret;
122
123	ret = i2c_master_send(client, &addr, sizeof(addr));
124	if (ret < 0)
125		goto fail;
126
127	ret = i2c_master_recv(client, &val, sizeof(val));
128	if (ret < 0)
129		goto fail;
130
131	return val;
132
133fail:
134	sil164_err(client, "Error %d reading from subaddress 0x%x\n",
135		   ret, addr);
136	return 0;
137}
138
139static void
140sil164_save_state(struct i2c_client *client, uint8_t *state)
141{
142	int i;
143
144	for (i = 0x8; i <= 0xe; i++)
145		state[i] = sil164_read(client, i);
146}
147
148static void
149sil164_restore_state(struct i2c_client *client, uint8_t *state)
150{
151	int i;
152
153	for (i = 0x8; i <= 0xe; i++)
154		sil164_write(client, i, state[i]);
155}
156
157static void
158sil164_set_power_state(struct i2c_client *client, bool on)
159{
160	uint8_t control0 = sil164_read(client, SIL164_CONTROL0);
161
162	if (on)
163		control0 |= SIL164_CONTROL0_POWER_ON;
164	else
165		control0 &= ~SIL164_CONTROL0_POWER_ON;
166
167	sil164_write(client, SIL164_CONTROL0, control0);
168}
169
170static void
171sil164_init_state(struct i2c_client *client,
172		  struct sil164_encoder_params *config,
173		  bool duallink)
174{
175	sil164_write(client, SIL164_CONTROL0,
176		     SIL164_CONTROL0_HSYNC_ON |
177		     SIL164_CONTROL0_VSYNC_ON |
178		     (config->input_edge ? SIL164_CONTROL0_EDGE_RISING : 0) |
179		     (config->input_width ? SIL164_CONTROL0_INPUT_24BIT : 0) |
180		     (config->input_dual ? SIL164_CONTROL0_DUAL_EDGE : 0));
181
182	sil164_write(client, SIL164_DETECT,
183		     SIL164_DETECT_INTR_STAT |
184		     SIL164_DETECT_OUT_MODE_RECEIVER);
185
186	sil164_write(client, SIL164_CONTROL1,
187		     (config->input_skew ? SIL164_CONTROL1_DESKEW_ENABLE : 0) |
188		     (((config->input_skew + 4) & 0x7)
189		      << SIL164_CONTROL1_DESKEW_INCR_SHIFT));
190
191	sil164_write(client, SIL164_CONTROL2,
192		     SIL164_CONTROL2_SYNC_CONT |
193		     (config->pll_filter ? 0 : SIL164_CONTROL2_FILTER_ENABLE) |
194		     (4 << SIL164_CONTROL2_FILTER_SETTING_SHIFT));
195
196	sil164_write(client, SIL164_PLLZONE, 0);
197
198	if (duallink)
199		sil164_write(client, SIL164_DUALLINK,
200			     SIL164_DUALLINK_ENABLE |
201			     (((config->duallink_skew + 4) & 0x7)
202			      << SIL164_DUALLINK_SKEW_SHIFT));
203	else
204		sil164_write(client, SIL164_DUALLINK, 0);
205}
206
207/* DRM encoder functions */
208
209static void
210sil164_encoder_set_config(struct drm_encoder *encoder, void *params)
211{
212	struct sil164_priv *priv = to_sil164_priv(encoder);
213
214	priv->config = *(struct sil164_encoder_params *)params;
215}
216
217static void
218sil164_encoder_dpms(struct drm_encoder *encoder, int mode)
219{
220	struct sil164_priv *priv = to_sil164_priv(encoder);
221	bool on = (mode == DRM_MODE_DPMS_ON);
222	bool duallink = (on && encoder->crtc->mode.clock > 165000);
223
224	sil164_set_power_state(drm_i2c_encoder_get_client(encoder), on);
225
226	if (priv->duallink_slave)
227		sil164_set_power_state(priv->duallink_slave, duallink);
228}
229
230static void
231sil164_encoder_save(struct drm_encoder *encoder)
232{
233	struct sil164_priv *priv = to_sil164_priv(encoder);
234
235	sil164_save_state(drm_i2c_encoder_get_client(encoder),
236			  priv->saved_state);
237
238	if (priv->duallink_slave)
239		sil164_save_state(priv->duallink_slave,
240				  priv->saved_slave_state);
241}
242
243static void
244sil164_encoder_restore(struct drm_encoder *encoder)
245{
246	struct sil164_priv *priv = to_sil164_priv(encoder);
247
248	sil164_restore_state(drm_i2c_encoder_get_client(encoder),
249			     priv->saved_state);
250
251	if (priv->duallink_slave)
252		sil164_restore_state(priv->duallink_slave,
253				     priv->saved_slave_state);
254}
255
256static int
257sil164_encoder_mode_valid(struct drm_encoder *encoder,
258			  struct drm_display_mode *mode)
259{
260	struct sil164_priv *priv = to_sil164_priv(encoder);
261
262	if (mode->clock < 32000)
263		return MODE_CLOCK_LOW;
264
265	if (mode->clock > 330000 ||
266	    (mode->clock > 165000 && !priv->duallink_slave))
267		return MODE_CLOCK_HIGH;
268
269	return MODE_OK;
270}
271
272static void
273sil164_encoder_mode_set(struct drm_encoder *encoder,
274			struct drm_display_mode *mode,
275			struct drm_display_mode *adjusted_mode)
276{
277	struct sil164_priv *priv = to_sil164_priv(encoder);
278	bool duallink = adjusted_mode->clock > 165000;
279
280	sil164_init_state(drm_i2c_encoder_get_client(encoder),
281			  &priv->config, duallink);
282
283	if (priv->duallink_slave)
284		sil164_init_state(priv->duallink_slave,
285				  &priv->config, duallink);
286
287	sil164_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
288}
289
290static enum drm_connector_status
291sil164_encoder_detect(struct drm_encoder *encoder,
292		      struct drm_connector *connector)
293{
294	struct i2c_client *client = drm_i2c_encoder_get_client(encoder);
295
296	if (sil164_read(client, SIL164_DETECT) & SIL164_DETECT_HOTPLUG_STAT)
297		return connector_status_connected;
298	else
299		return connector_status_disconnected;
300}
301
302static int
303sil164_encoder_get_modes(struct drm_encoder *encoder,
304			 struct drm_connector *connector)
305{
306	return 0;
307}
308
309static int
310sil164_encoder_create_resources(struct drm_encoder *encoder,
311				struct drm_connector *connector)
312{
313	return 0;
314}
315
316static int
317sil164_encoder_set_property(struct drm_encoder *encoder,
318			    struct drm_connector *connector,
319			    struct drm_property *property,
320			    uint64_t val)
321{
322	return 0;
323}
324
325static void
326sil164_encoder_destroy(struct drm_encoder *encoder)
327{
328	struct sil164_priv *priv = to_sil164_priv(encoder);
329
330	i2c_unregister_device(priv->duallink_slave);
331
332	kfree(priv);
333	drm_i2c_encoder_destroy(encoder);
334}
335
336static const struct drm_encoder_slave_funcs sil164_encoder_funcs = {
337	.set_config = sil164_encoder_set_config,
338	.destroy = sil164_encoder_destroy,
339	.dpms = sil164_encoder_dpms,
340	.save = sil164_encoder_save,
341	.restore = sil164_encoder_restore,
342	.mode_valid = sil164_encoder_mode_valid,
343	.mode_set = sil164_encoder_mode_set,
344	.detect = sil164_encoder_detect,
345	.get_modes = sil164_encoder_get_modes,
346	.create_resources = sil164_encoder_create_resources,
347	.set_property = sil164_encoder_set_property,
348};
349
350/* I2C driver functions */
351
352static int
353sil164_probe(struct i2c_client *client)
354{
355	int vendor = sil164_read(client, SIL164_VENDOR_HI) << 8 |
356		sil164_read(client, SIL164_VENDOR_LO);
357	int device = sil164_read(client, SIL164_DEVICE_HI) << 8 |
358		sil164_read(client, SIL164_DEVICE_LO);
359	int rev = sil164_read(client, SIL164_REVISION);
360
361	if (vendor != 0x1 || device != 0x6) {
362		sil164_dbg(client, "Unknown device %x:%x.%x\n",
363			   vendor, device, rev);
364		return -ENODEV;
365	}
366
367	sil164_info(client, "Detected device %x:%x.%x\n",
368		    vendor, device, rev);
369
370	return 0;
371}
372
373static struct i2c_client *
374sil164_detect_slave(struct i2c_client *client)
375{
376	struct i2c_adapter *adap = client->adapter;
377	struct i2c_msg msg = {
378		.addr = SIL164_I2C_ADDR_SLAVE,
379		.len = 0,
380	};
381	const struct i2c_board_info info = {
382		I2C_BOARD_INFO("sil164", SIL164_I2C_ADDR_SLAVE)
383	};
384
385	if (i2c_transfer(adap, &msg, 1) != 1) {
386		sil164_dbg(adap, "No dual-link slave found.");
387		return NULL;
388	}
389
390	return i2c_new_client_device(adap, &info);
391}
392
393static int
394sil164_encoder_init(struct i2c_client *client,
395		    struct drm_device *dev,
396		    struct drm_encoder_slave *encoder)
397{
398	struct sil164_priv *priv;
399	struct i2c_client *slave_client;
400
401	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
402	if (!priv)
403		return -ENOMEM;
404
405	encoder->slave_priv = priv;
406	encoder->slave_funcs = &sil164_encoder_funcs;
407
408	slave_client = sil164_detect_slave(client);
409	if (!IS_ERR(slave_client))
410		priv->duallink_slave = slave_client;
411
412	return 0;
413}
414
415static const struct i2c_device_id sil164_ids[] = {
416	{ "sil164", 0 },
417	{ }
418};
419MODULE_DEVICE_TABLE(i2c, sil164_ids);
420
421static struct drm_i2c_encoder_driver sil164_driver = {
422	.i2c_driver = {
423		.probe = sil164_probe,
424		.driver = {
425			.name = "sil164",
426		},
427		.id_table = sil164_ids,
428	},
429	.encoder_init = sil164_encoder_init,
430};
431
432/* Module initialization */
433
434static int __init
435sil164_init(void)
436{
437	return drm_i2c_encoder_register(THIS_MODULE, &sil164_driver);
438}
439
440static void __exit
441sil164_exit(void)
442{
443	drm_i2c_encoder_unregister(&sil164_driver);
444}
445
446MODULE_AUTHOR("Francisco Jerez <currojerez@riseup.net>");
447MODULE_DESCRIPTION("Silicon Image sil164 TMDS transmitter driver");
448MODULE_LICENSE("GPL and additional rights");
449
450module_init(sil164_init);
451module_exit(sil164_exit);
452