1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
|
/*
* NXP PTN3460 DP/LVDS bridge driver
*
* Copyright (C) 2013 Google, Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include "drmP.h"
#include "drm_edid.h"
#include "drm_crtc.h"
#include "drm_crtc_helper.h"
#include "bridge/ptn3460.h"
#define PTN3460_EDID_ADDR 0x0
#define PTN3460_EDID_EMULATION_ADDR 0x84
#define PTN3460_EDID_ENABLE_EMULATION 0
#define PTN3460_EDID_EMULATION_SELECTION 1
#define PTN3460_EDID_SRAM_LOAD_ADDR 0x85
struct ptn3460_bridge {
struct drm_connector connector;
struct i2c_client *client;
struct drm_encoder *encoder;
struct drm_bridge *bridge;
struct edid *edid;
int gpio_pd_n;
int gpio_rst_n;
u32 edid_emulation;
bool enabled;
};
static int ptn3460_read_bytes(struct ptn3460_bridge *ptn_bridge, char addr,
u8 *buf, int len)
{
int ret;
ret = i2c_master_send(ptn_bridge->client, &addr, 1);
if (ret <= 0) {
DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
return ret;
}
ret = i2c_master_recv(ptn_bridge->client, buf, len);
if (ret <= 0) {
DRM_ERROR("Failed to recv i2c data, ret=%d\n", ret);
return ret;
}
return 0;
}
static int ptn3460_write_byte(struct ptn3460_bridge *ptn_bridge, char addr,
char val)
{
int ret;
char buf[2];
buf[0] = addr;
buf[1] = val;
ret = i2c_master_send(ptn_bridge->client, buf, ARRAY_SIZE(buf));
if (ret <= 0) {
DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
return ret;
}
return 0;
}
static int ptn3460_select_edid(struct ptn3460_bridge *ptn_bridge)
{
int ret;
char val;
/* Load the selected edid into SRAM (accessed at PTN3460_EDID_ADDR) */
ret = ptn3460_write_byte(ptn_bridge, PTN3460_EDID_SRAM_LOAD_ADDR,
ptn_bridge->edid_emulation);
if (ret) {
DRM_ERROR("Failed to transfer edid to sram, ret=%d\n", ret);
return ret;
}
/* Enable EDID emulation and select the desired EDID */
val = 1 << PTN3460_EDID_ENABLE_EMULATION |
ptn_bridge->edid_emulation << PTN3460_EDID_EMULATION_SELECTION;
ret = ptn3460_write_byte(ptn_bridge, PTN3460_EDID_EMULATION_ADDR, val);
if (ret) {
DRM_ERROR("Failed to write edid value, ret=%d\n", ret);
return ret;
}
return 0;
}
static void ptn3460_pre_enable(struct drm_bridge *bridge)
{
struct ptn3460_bridge *ptn_bridge = bridge->driver_private;
int ret;
if (ptn_bridge->enabled)
return;
if (gpio_is_valid(ptn_bridge->gpio_pd_n))
gpio_set_value(ptn_bridge->gpio_pd_n, 1);
if (gpio_is_valid(ptn_bridge->gpio_rst_n)) {
gpio_set_value(ptn_bridge->gpio_rst_n, 0);
udelay(10);
gpio_set_value(ptn_bridge->gpio_rst_n, 1);
}
/*
* There's a bug in the PTN chip where it falsely asserts hotplug before
* it is fully functional. We're forced to wait for the maximum start up
* time specified in the chip's datasheet to make sure we're really up.
*/
msleep(90);
ret = ptn3460_select_edid(ptn_bridge);
if (ret)
DRM_ERROR("Select edid failed ret=%d\n", ret);
ptn_bridge->enabled = true;
}
static void ptn3460_enable(struct drm_bridge *bridge)
{
}
static void ptn3460_disable(struct drm_bridge *bridge)
{
struct ptn3460_bridge *ptn_bridge = bridge->driver_private;
if (!ptn_bridge->enabled)
return;
ptn_bridge->enabled = false;
if (gpio_is_valid(ptn_bridge->gpio_rst_n))
gpio_set_value(ptn_bridge->gpio_rst_n, 1);
if (gpio_is_valid(ptn_bridge->gpio_pd_n))
gpio_set_value(ptn_bridge->gpio_pd_n, 0);
}
static void ptn3460_post_disable(struct drm_bridge *bridge)
{
}
void ptn3460_bridge_destroy(struct drm_bridge *bridge)
{
struct ptn3460_bridge *ptn_bridge = bridge->driver_private;
drm_bridge_cleanup(bridge);
if (gpio_is_valid(ptn_bridge->gpio_pd_n))
gpio_free(ptn_bridge->gpio_pd_n);
if (gpio_is_valid(ptn_bridge->gpio_rst_n))
gpio_free(ptn_bridge->gpio_rst_n);
/* Nothing else to free, we've got devm allocated memory */
}
struct drm_bridge_funcs ptn3460_bridge_funcs = {
.pre_enable = ptn3460_pre_enable,
.enable = ptn3460_enable,
.disable = ptn3460_disable,
.post_disable = ptn3460_post_disable,
.destroy = ptn3460_bridge_destroy,
};
int ptn3460_get_modes(struct drm_connector *connector)
{
struct ptn3460_bridge *ptn_bridge;
u8 *edid;
int ret, num_modes;
bool power_off;
ptn_bridge = container_of(connector, struct ptn3460_bridge, connector);
if (ptn_bridge->edid)
return drm_add_edid_modes(connector, ptn_bridge->edid);
power_off = !ptn_bridge->enabled;
ptn3460_pre_enable(ptn_bridge->bridge);
edid = kmalloc(EDID_LENGTH, GFP_KERNEL);
if (!edid) {
DRM_ERROR("Failed to allocate edid\n");
return 0;
}
ret = ptn3460_read_bytes(ptn_bridge, PTN3460_EDID_ADDR, edid,
EDID_LENGTH);
if (ret) {
kfree(edid);
num_modes = 0;
goto out;
}
ptn_bridge->edid = (struct edid *)edid;
drm_mode_connector_update_edid_property(connector, ptn_bridge->edid);
num_modes = drm_add_edid_modes(connector, ptn_bridge->edid);
out:
if (power_off)
ptn3460_disable(ptn_bridge->bridge);
return num_modes;
}
static int ptn3460_mode_valid(struct drm_connector *connector,
struct drm_display_mode *mode)
{
return MODE_OK;
}
struct drm_encoder *ptn3460_best_encoder(struct drm_connector *connector)
{
struct ptn3460_bridge *ptn_bridge;
ptn_bridge = container_of(connector, struct ptn3460_bridge, connector);
return ptn_bridge->encoder;
}
struct drm_connector_helper_funcs ptn3460_connector_helper_funcs = {
.get_modes = ptn3460_get_modes,
.mode_valid = ptn3460_mode_valid,
.best_encoder = ptn3460_best_encoder,
};
enum drm_connector_status ptn3460_detect(struct drm_connector *connector,
bool force)
{
return connector_status_connected;
}
void ptn3460_connector_destroy(struct drm_connector *connector)
{
drm_connector_cleanup(connector);
}
struct drm_connector_funcs ptn3460_connector_funcs = {
.dpms = drm_helper_connector_dpms,
.fill_modes = drm_helper_probe_single_connector_modes,
.detect = ptn3460_detect,
.destroy = ptn3460_connector_destroy,
};
int ptn3460_init(struct drm_device *dev, struct drm_encoder *encoder,
struct i2c_client *client, struct device_node *node)
{
int ret;
struct drm_bridge *bridge;
struct ptn3460_bridge *ptn_bridge;
bridge = devm_kzalloc(dev->dev, sizeof(*bridge), GFP_KERNEL);
if (!bridge) {
DRM_ERROR("Failed to allocate drm bridge\n");
return -ENOMEM;
}
ptn_bridge = devm_kzalloc(dev->dev, sizeof(*ptn_bridge), GFP_KERNEL);
if (!ptn_bridge) {
DRM_ERROR("Failed to allocate ptn bridge\n");
return -ENOMEM;
}
ptn_bridge->client = client;
ptn_bridge->encoder = encoder;
ptn_bridge->bridge = bridge;
ptn_bridge->gpio_pd_n = of_get_named_gpio(node, "powerdown-gpio", 0);
if (gpio_is_valid(ptn_bridge->gpio_pd_n)) {
ret = gpio_request_one(ptn_bridge->gpio_pd_n,
GPIOF_OUT_INIT_HIGH, "PTN3460_PD_N");
if (ret) {
DRM_ERROR("Request powerdown-gpio failed (%d)\n", ret);
return ret;
}
}
ptn_bridge->gpio_rst_n = of_get_named_gpio(node, "reset-gpio", 0);
if (gpio_is_valid(ptn_bridge->gpio_rst_n)) {
/*
* Request the reset pin low to avoid the bridge being
* initialized prematurely
*/
ret = gpio_request_one(
|