2 * NXP PTN3460 DP/LVDS bridge driver
4 * Copyright (C) 2013 Google, Inc.
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
16 #include <linux/delay.h>
17 #include <linux/gpio.h>
18 #include <linux/gpio/consumer.h>
19 #include <linux/i2c.h>
20 #include <linux/module.h>
22 #include <linux/of_gpio.h>
23 #include <drm/drm_atomic_helper.h>
24 #include <drm/drm_crtc.h>
25 #include <drm/drm_crtc_helper.h>
26 #include <drm/drm_edid.h>
27 #include <drm/drm_of.h>
28 #include <drm/drm_panel.h>
31 #define PTN3460_EDID_ADDR 0x0
32 #define PTN3460_EDID_EMULATION_ADDR 0x84
33 #define PTN3460_EDID_ENABLE_EMULATION 0
34 #define PTN3460_EDID_EMULATION_SELECTION 1
35 #define PTN3460_EDID_SRAM_LOAD_ADDR 0x85
37 struct ptn3460_bridge
{
38 struct drm_connector connector
;
39 struct i2c_client
*client
;
40 struct drm_bridge bridge
;
42 struct drm_panel
*panel
;
43 struct gpio_desc
*gpio_pd_n
;
44 struct gpio_desc
*gpio_rst_n
;
49 static inline struct ptn3460_bridge
*
50 bridge_to_ptn3460(struct drm_bridge
*bridge
)
52 return container_of(bridge
, struct ptn3460_bridge
, bridge
);
55 static inline struct ptn3460_bridge
*
56 connector_to_ptn3460(struct drm_connector
*connector
)
58 return container_of(connector
, struct ptn3460_bridge
, connector
);
61 static int ptn3460_read_bytes(struct ptn3460_bridge
*ptn_bridge
, char addr
,
66 ret
= i2c_master_send(ptn_bridge
->client
, &addr
, 1);
68 DRM_ERROR("Failed to send i2c command, ret=%d\n", ret
);
72 ret
= i2c_master_recv(ptn_bridge
->client
, buf
, len
);
74 DRM_ERROR("Failed to recv i2c data, ret=%d\n", ret
);
81 static int ptn3460_write_byte(struct ptn3460_bridge
*ptn_bridge
, char addr
,
90 ret
= i2c_master_send(ptn_bridge
->client
, buf
, ARRAY_SIZE(buf
));
92 DRM_ERROR("Failed to send i2c command, ret=%d\n", ret
);
99 static int ptn3460_select_edid(struct ptn3460_bridge
*ptn_bridge
)
104 /* Load the selected edid into SRAM (accessed at PTN3460_EDID_ADDR) */
105 ret
= ptn3460_write_byte(ptn_bridge
, PTN3460_EDID_SRAM_LOAD_ADDR
,
106 ptn_bridge
->edid_emulation
);
108 DRM_ERROR("Failed to transfer EDID to sram, ret=%d\n", ret
);
112 /* Enable EDID emulation and select the desired EDID */
113 val
= 1 << PTN3460_EDID_ENABLE_EMULATION
|
114 ptn_bridge
->edid_emulation
<< PTN3460_EDID_EMULATION_SELECTION
;
116 ret
= ptn3460_write_byte(ptn_bridge
, PTN3460_EDID_EMULATION_ADDR
, val
);
118 DRM_ERROR("Failed to write EDID value, ret=%d\n", ret
);
125 static void ptn3460_pre_enable(struct drm_bridge
*bridge
)
127 struct ptn3460_bridge
*ptn_bridge
= bridge_to_ptn3460(bridge
);
130 if (ptn_bridge
->enabled
)
133 gpiod_set_value(ptn_bridge
->gpio_pd_n
, 1);
135 gpiod_set_value(ptn_bridge
->gpio_rst_n
, 0);
136 usleep_range(10, 20);
137 gpiod_set_value(ptn_bridge
->gpio_rst_n
, 1);
139 if (drm_panel_prepare(ptn_bridge
->panel
)) {
140 DRM_ERROR("failed to prepare panel\n");
145 * There's a bug in the PTN chip where it falsely asserts hotplug before
146 * it is fully functional. We're forced to wait for the maximum start up
147 * time specified in the chip's datasheet to make sure we're really up.
151 ret
= ptn3460_select_edid(ptn_bridge
);
153 DRM_ERROR("Select EDID failed ret=%d\n", ret
);
155 ptn_bridge
->enabled
= true;
158 static void ptn3460_enable(struct drm_bridge
*bridge
)
160 struct ptn3460_bridge
*ptn_bridge
= bridge_to_ptn3460(bridge
);
162 if (drm_panel_enable(ptn_bridge
->panel
)) {
163 DRM_ERROR("failed to enable panel\n");
168 static void ptn3460_disable(struct drm_bridge
*bridge
)
170 struct ptn3460_bridge
*ptn_bridge
= bridge_to_ptn3460(bridge
);
172 if (!ptn_bridge
->enabled
)
175 ptn_bridge
->enabled
= false;
177 if (drm_panel_disable(ptn_bridge
->panel
)) {
178 DRM_ERROR("failed to disable panel\n");
182 gpiod_set_value(ptn_bridge
->gpio_rst_n
, 1);
183 gpiod_set_value(ptn_bridge
->gpio_pd_n
, 0);
186 static void ptn3460_post_disable(struct drm_bridge
*bridge
)
188 struct ptn3460_bridge
*ptn_bridge
= bridge_to_ptn3460(bridge
);
190 if (drm_panel_unprepare(ptn_bridge
->panel
)) {
191 DRM_ERROR("failed to unprepare panel\n");
196 static int ptn3460_get_modes(struct drm_connector
*connector
)
198 struct ptn3460_bridge
*ptn_bridge
;
200 int ret
, num_modes
= 0;
203 ptn_bridge
= connector_to_ptn3460(connector
);
205 if (ptn_bridge
->edid
)
206 return drm_add_edid_modes(connector
, ptn_bridge
->edid
);
208 power_off
= !ptn_bridge
->enabled
;
209 ptn3460_pre_enable(&ptn_bridge
->bridge
);
211 edid
= kmalloc(EDID_LENGTH
, GFP_KERNEL
);
213 DRM_ERROR("Failed to allocate EDID\n");
217 ret
= ptn3460_read_bytes(ptn_bridge
, PTN3460_EDID_ADDR
, edid
,
224 ptn_bridge
->edid
= (struct edid
*)edid
;
225 drm_connector_update_edid_property(connector
, ptn_bridge
->edid
);
227 num_modes
= drm_add_edid_modes(connector
, ptn_bridge
->edid
);
231 ptn3460_disable(&ptn_bridge
->bridge
);
236 static const struct drm_connector_helper_funcs ptn3460_connector_helper_funcs
= {
237 .get_modes
= ptn3460_get_modes
,
240 static const struct drm_connector_funcs ptn3460_connector_funcs
= {
241 .fill_modes
= drm_helper_probe_single_connector_modes
,
242 .destroy
= drm_connector_cleanup
,
243 .reset
= drm_atomic_helper_connector_reset
,
244 .atomic_duplicate_state
= drm_atomic_helper_connector_duplicate_state
,
245 .atomic_destroy_state
= drm_atomic_helper_connector_destroy_state
,
248 static int ptn3460_bridge_attach(struct drm_bridge
*bridge
)
250 struct ptn3460_bridge
*ptn_bridge
= bridge_to_ptn3460(bridge
);
253 if (!bridge
->encoder
) {
254 DRM_ERROR("Parent encoder object not found");
258 ptn_bridge
->connector
.polled
= DRM_CONNECTOR_POLL_HPD
;
259 ret
= drm_connector_init(bridge
->dev
, &ptn_bridge
->connector
,
260 &ptn3460_connector_funcs
, DRM_MODE_CONNECTOR_LVDS
);
262 DRM_ERROR("Failed to initialize connector with drm\n");
265 drm_connector_helper_add(&ptn_bridge
->connector
,
266 &ptn3460_connector_helper_funcs
);
267 drm_connector_register(&ptn_bridge
->connector
);
268 drm_mode_connector_attach_encoder(&ptn_bridge
->connector
,
271 if (ptn_bridge
->panel
)
272 drm_panel_attach(ptn_bridge
->panel
, &ptn_bridge
->connector
);
274 drm_helper_hpd_irq_event(ptn_bridge
->connector
.dev
);
279 static const struct drm_bridge_funcs ptn3460_bridge_funcs
= {
280 .pre_enable
= ptn3460_pre_enable
,
281 .enable
= ptn3460_enable
,
282 .disable
= ptn3460_disable
,
283 .post_disable
= ptn3460_post_disable
,
284 .attach
= ptn3460_bridge_attach
,
287 static int ptn3460_probe(struct i2c_client
*client
,
288 const struct i2c_device_id
*id
)
290 struct device
*dev
= &client
->dev
;
291 struct ptn3460_bridge
*ptn_bridge
;
294 ptn_bridge
= devm_kzalloc(dev
, sizeof(*ptn_bridge
), GFP_KERNEL
);
299 ret
= drm_of_find_panel_or_bridge(dev
->of_node
, 0, 0, &ptn_bridge
->panel
, NULL
);
303 ptn_bridge
->client
= client
;
305 ptn_bridge
->gpio_pd_n
= devm_gpiod_get(&client
->dev
, "powerdown",
307 if (IS_ERR(ptn_bridge
->gpio_pd_n
)) {
308 ret
= PTR_ERR(ptn_bridge
->gpio_pd_n
);
309 dev_err(dev
, "cannot get gpio_pd_n %d\n", ret
);
314 * Request the reset pin low to avoid the bridge being
315 * initialized prematurely
317 ptn_bridge
->gpio_rst_n
= devm_gpiod_get(&client
->dev
, "reset",
319 if (IS_ERR(ptn_bridge
->gpio_rst_n
)) {
320 ret
= PTR_ERR(ptn_bridge
->gpio_rst_n
);
321 DRM_ERROR("cannot get gpio_rst_n %d\n", ret
);
325 ret
= of_property_read_u32(dev
->of_node
, "edid-emulation",
326 &ptn_bridge
->edid_emulation
);
328 dev_err(dev
, "Can't read EDID emulation value\n");
332 ptn_bridge
->bridge
.funcs
= &ptn3460_bridge_funcs
;
333 ptn_bridge
->bridge
.of_node
= dev
->of_node
;
334 drm_bridge_add(&ptn_bridge
->bridge
);
336 i2c_set_clientdata(client
, ptn_bridge
);
341 static int ptn3460_remove(struct i2c_client
*client
)
343 struct ptn3460_bridge
*ptn_bridge
= i2c_get_clientdata(client
);
345 drm_bridge_remove(&ptn_bridge
->bridge
);
350 static const struct i2c_device_id ptn3460_i2c_table
[] = {
354 MODULE_DEVICE_TABLE(i2c
, ptn3460_i2c_table
);
356 static const struct of_device_id ptn3460_match
[] = {
357 { .compatible
= "nxp,ptn3460" },
360 MODULE_DEVICE_TABLE(of
, ptn3460_match
);
362 static struct i2c_driver ptn3460_driver
= {
363 .id_table
= ptn3460_i2c_table
,
364 .probe
= ptn3460_probe
,
365 .remove
= ptn3460_remove
,
367 .name
= "nxp,ptn3460",
368 .of_match_table
= ptn3460_match
,
371 module_i2c_driver(ptn3460_driver
);
373 MODULE_AUTHOR("Sean Paul <seanpaul@chromium.org>");
374 MODULE_DESCRIPTION("NXP ptn3460 eDP-LVDS converter driver");
375 MODULE_LICENSE("GPL v2");