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8#include <linux/delay.h>
9#include <linux/gpio/consumer.h>
10#include <linux/i2c.h>
11#include <linux/module.h>
12#include <linux/of.h>
13#include <drm/drm_atomic_helper.h>
14#include <drm/drm_bridge.h>
15#include <drm/drm_crtc.h>
16#include <drm/drm_edid.h>
17#include <drm/drm_of.h>
18#include <drm/drm_panel.h>
19#include <drm/drm_print.h>
20#include <drm/drm_probe_helper.h>
21
22#define PTN3460_EDID_ADDR 0x0
23#define PTN3460_EDID_EMULATION_ADDR 0x84
24#define PTN3460_EDID_ENABLE_EMULATION 0
25#define PTN3460_EDID_EMULATION_SELECTION 1
26#define PTN3460_EDID_SRAM_LOAD_ADDR 0x85
27
28struct ptn3460_bridge {
29 struct drm_connector connector;
30 struct i2c_client *client;
31 struct drm_bridge bridge;
32 struct drm_bridge *panel_bridge;
33 struct gpio_desc *gpio_pd_n;
34 struct gpio_desc *gpio_rst_n;
35 u32 edid_emulation;
36 bool enabled;
37};
38
39static inline struct ptn3460_bridge *
40 bridge_to_ptn3460(struct drm_bridge *bridge)
41{
42 return container_of(bridge, struct ptn3460_bridge, bridge);
43}
44
45static inline struct ptn3460_bridge *
46 connector_to_ptn3460(struct drm_connector *connector)
47{
48 return container_of(connector, struct ptn3460_bridge, connector);
49}
50
51static int ptn3460_read_bytes(struct ptn3460_bridge *ptn_bridge, char addr,
52 u8 *buf, int len)
53{
54 int ret;
55
56 ret = i2c_master_send(ptn_bridge->client, &addr, 1);
57 if (ret <= 0) {
58 DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
59 return ret;
60 }
61
62 ret = i2c_master_recv(ptn_bridge->client, buf, len);
63 if (ret <= 0) {
64 DRM_ERROR("Failed to recv i2c data, ret=%d\n", ret);
65 return ret;
66 }
67
68 return 0;
69}
70
71static int ptn3460_write_byte(struct ptn3460_bridge *ptn_bridge, char addr,
72 char val)
73{
74 int ret;
75 char buf[2];
76
77 buf[0] = addr;
78 buf[1] = val;
79
80 ret = i2c_master_send(ptn_bridge->client, buf, ARRAY_SIZE(buf));
81 if (ret <= 0) {
82 DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
83 return ret;
84 }
85
86 return 0;
87}
88
89static int ptn3460_select_edid(struct ptn3460_bridge *ptn_bridge)
90{
91 int ret;
92 char val;
93
94
95 ret = ptn3460_write_byte(ptn_bridge, PTN3460_EDID_SRAM_LOAD_ADDR,
96 ptn_bridge->edid_emulation);
97 if (ret) {
98 DRM_ERROR("Failed to transfer EDID to sram, ret=%d\n", ret);
99 return ret;
100 }
101
102
103 val = 1 << PTN3460_EDID_ENABLE_EMULATION |
104 ptn_bridge->edid_emulation << PTN3460_EDID_EMULATION_SELECTION;
105
106 ret = ptn3460_write_byte(ptn_bridge, PTN3460_EDID_EMULATION_ADDR, val);
107 if (ret) {
108 DRM_ERROR("Failed to write EDID value, ret=%d\n", ret);
109 return ret;
110 }
111
112 return 0;
113}
114
115static void ptn3460_pre_enable(struct drm_bridge *bridge)
116{
117 struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge);
118 int ret;
119
120 if (ptn_bridge->enabled)
121 return;
122
123 gpiod_set_value(ptn_bridge->gpio_pd_n, 1);
124
125 gpiod_set_value(ptn_bridge->gpio_rst_n, 0);
126 usleep_range(10, 20);
127 gpiod_set_value(ptn_bridge->gpio_rst_n, 1);
128
129
130
131
132
133
134 msleep(90);
135
136 ret = ptn3460_select_edid(ptn_bridge);
137 if (ret)
138 DRM_ERROR("Select EDID failed ret=%d\n", ret);
139
140 ptn_bridge->enabled = true;
141}
142
143static void ptn3460_disable(struct drm_bridge *bridge)
144{
145 struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge);
146
147 if (!ptn_bridge->enabled)
148 return;
149
150 ptn_bridge->enabled = false;
151
152 gpiod_set_value(ptn_bridge->gpio_rst_n, 1);
153 gpiod_set_value(ptn_bridge->gpio_pd_n, 0);
154}
155
156
157static struct edid *ptn3460_get_edid(struct drm_bridge *bridge,
158 struct drm_connector *connector)
159{
160 struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge);
161 bool power_off;
162 u8 *edid;
163 int ret;
164
165 power_off = !ptn_bridge->enabled;
166 ptn3460_pre_enable(&ptn_bridge->bridge);
167
168 edid = kmalloc(EDID_LENGTH, GFP_KERNEL);
169 if (!edid) {
170 DRM_ERROR("Failed to allocate EDID\n");
171 goto out;
172 }
173
174 ret = ptn3460_read_bytes(ptn_bridge, PTN3460_EDID_ADDR, edid,
175 EDID_LENGTH);
176 if (ret) {
177 kfree(edid);
178 edid = NULL;
179 goto out;
180 }
181
182out:
183 if (power_off)
184 ptn3460_disable(&ptn_bridge->bridge);
185
186 return (struct edid *)edid;
187}
188
189static int ptn3460_connector_get_modes(struct drm_connector *connector)
190{
191 struct ptn3460_bridge *ptn_bridge = connector_to_ptn3460(connector);
192 struct edid *edid;
193 int num_modes;
194
195 edid = ptn3460_get_edid(&ptn_bridge->bridge, connector);
196 drm_connector_update_edid_property(connector, edid);
197 num_modes = drm_add_edid_modes(connector, edid);
198 kfree(edid);
199
200 return num_modes;
201}
202
203static const struct drm_connector_helper_funcs ptn3460_connector_helper_funcs = {
204 .get_modes = ptn3460_connector_get_modes,
205};
206
207static const struct drm_connector_funcs ptn3460_connector_funcs = {
208 .fill_modes = drm_helper_probe_single_connector_modes,
209 .destroy = drm_connector_cleanup,
210 .reset = drm_atomic_helper_connector_reset,
211 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
212 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
213};
214
215static int ptn3460_bridge_attach(struct drm_bridge *bridge,
216 enum drm_bridge_attach_flags flags)
217{
218 struct ptn3460_bridge *ptn_bridge = bridge_to_ptn3460(bridge);
219 int ret;
220
221
222 ret = drm_bridge_attach(bridge->encoder, ptn_bridge->panel_bridge,
223 bridge, flags | DRM_BRIDGE_ATTACH_NO_CONNECTOR);
224 if (ret < 0)
225 return ret;
226
227 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
228 return 0;
229
230 if (!bridge->encoder) {
231 DRM_ERROR("Parent encoder object not found");
232 return -ENODEV;
233 }
234
235 ptn_bridge->connector.polled = DRM_CONNECTOR_POLL_HPD;
236 ret = drm_connector_init(bridge->dev, &ptn_bridge->connector,
237 &ptn3460_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
238 if (ret) {
239 DRM_ERROR("Failed to initialize connector with drm\n");
240 return ret;
241 }
242 drm_connector_helper_add(&ptn_bridge->connector,
243 &ptn3460_connector_helper_funcs);
244 drm_connector_register(&ptn_bridge->connector);
245 drm_connector_attach_encoder(&ptn_bridge->connector,
246 bridge->encoder);
247
248 drm_helper_hpd_irq_event(ptn_bridge->connector.dev);
249
250 return ret;
251}
252
253static const struct drm_bridge_funcs ptn3460_bridge_funcs = {
254 .pre_enable = ptn3460_pre_enable,
255 .disable = ptn3460_disable,
256 .attach = ptn3460_bridge_attach,
257 .get_edid = ptn3460_get_edid,
258};
259
260static int ptn3460_probe(struct i2c_client *client,
261 const struct i2c_device_id *id)
262{
263 struct device *dev = &client->dev;
264 struct ptn3460_bridge *ptn_bridge;
265 struct drm_bridge *panel_bridge;
266 struct drm_panel *panel;
267 int ret;
268
269 ptn_bridge = devm_kzalloc(dev, sizeof(*ptn_bridge), GFP_KERNEL);
270 if (!ptn_bridge) {
271 return -ENOMEM;
272 }
273
274 ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, &panel, NULL);
275 if (ret)
276 return ret;
277
278 panel_bridge = devm_drm_panel_bridge_add(dev, panel);
279 if (IS_ERR(panel_bridge))
280 return PTR_ERR(panel_bridge);
281
282 ptn_bridge->panel_bridge = panel_bridge;
283 ptn_bridge->client = client;
284
285 ptn_bridge->gpio_pd_n = devm_gpiod_get(&client->dev, "powerdown",
286 GPIOD_OUT_HIGH);
287 if (IS_ERR(ptn_bridge->gpio_pd_n)) {
288 ret = PTR_ERR(ptn_bridge->gpio_pd_n);
289 dev_err(dev, "cannot get gpio_pd_n %d\n", ret);
290 return ret;
291 }
292
293
294
295
296
297 ptn_bridge->gpio_rst_n = devm_gpiod_get(&client->dev, "reset",
298 GPIOD_OUT_LOW);
299 if (IS_ERR(ptn_bridge->gpio_rst_n)) {
300 ret = PTR_ERR(ptn_bridge->gpio_rst_n);
301 DRM_ERROR("cannot get gpio_rst_n %d\n", ret);
302 return ret;
303 }
304
305 ret = of_property_read_u32(dev->of_node, "edid-emulation",
306 &ptn_bridge->edid_emulation);
307 if (ret) {
308 dev_err(dev, "Can't read EDID emulation value\n");
309 return ret;
310 }
311
312 ptn_bridge->bridge.funcs = &ptn3460_bridge_funcs;
313 ptn_bridge->bridge.ops = DRM_BRIDGE_OP_EDID;
314 ptn_bridge->bridge.type = DRM_MODE_CONNECTOR_LVDS;
315 ptn_bridge->bridge.of_node = dev->of_node;
316 drm_bridge_add(&ptn_bridge->bridge);
317
318 i2c_set_clientdata(client, ptn_bridge);
319
320 return 0;
321}
322
323static int ptn3460_remove(struct i2c_client *client)
324{
325 struct ptn3460_bridge *ptn_bridge = i2c_get_clientdata(client);
326
327 drm_bridge_remove(&ptn_bridge->bridge);
328
329 return 0;
330}
331
332static const struct i2c_device_id ptn3460_i2c_table[] = {
333 {"ptn3460", 0},
334 {},
335};
336MODULE_DEVICE_TABLE(i2c, ptn3460_i2c_table);
337
338static const struct of_device_id ptn3460_match[] = {
339 { .compatible = "nxp,ptn3460" },
340 {},
341};
342MODULE_DEVICE_TABLE(of, ptn3460_match);
343
344static struct i2c_driver ptn3460_driver = {
345 .id_table = ptn3460_i2c_table,
346 .probe = ptn3460_probe,
347 .remove = ptn3460_remove,
348 .driver = {
349 .name = "nxp,ptn3460",
350 .of_match_table = ptn3460_match,
351 },
352};
353module_i2c_driver(ptn3460_driver);
354
355MODULE_AUTHOR("Sean Paul <seanpaul@chromium.org>");
356MODULE_DESCRIPTION("NXP ptn3460 eDP-LVDS converter driver");
357MODULE_LICENSE("GPL v2");
358
