1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * ZynqMP DisplayPort Subsystem Driver
4 *
5 * Copyright (C) 2017 - 2020 Xilinx, Inc.
6 *
7 * Authors:
8 * - Hyun Woo Kwon <hyun.kwon@xilinx.com>
9 * - Laurent Pinchart <laurent.pinchart@ideasonboard.com>
10 */
11
12 #include <linux/clk.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/module.h>
15 #include <linux/of_graph.h>
16 #include <linux/of_reserved_mem.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/slab.h>
20
21 #include <drm/drm_atomic_helper.h>
22 #include <drm/drm_bridge.h>
23 #include <drm/drm_modeset_helper.h>
24 #include <drm/drm_module.h>
25
26 #include "zynqmp_disp.h"
27 #include "zynqmp_dp.h"
28 #include "zynqmp_dpsub.h"
29 #include "zynqmp_kms.h"
30
31 /* -----------------------------------------------------------------------------
32 * Power Management
33 */
34
zynqmp_dpsub_suspend(struct device * dev)35 static int __maybe_unused zynqmp_dpsub_suspend(struct device *dev)
36 {
37 struct zynqmp_dpsub *dpsub = dev_get_drvdata(dev);
38
39 if (!dpsub->drm)
40 return 0;
41
42 return drm_mode_config_helper_suspend(&dpsub->drm->dev);
43 }
44
zynqmp_dpsub_resume(struct device * dev)45 static int __maybe_unused zynqmp_dpsub_resume(struct device *dev)
46 {
47 struct zynqmp_dpsub *dpsub = dev_get_drvdata(dev);
48
49 if (!dpsub->drm)
50 return 0;
51
52 return drm_mode_config_helper_resume(&dpsub->drm->dev);
53 }
54
55 static const struct dev_pm_ops zynqmp_dpsub_pm_ops = {
56 SET_SYSTEM_SLEEP_PM_OPS(zynqmp_dpsub_suspend, zynqmp_dpsub_resume)
57 };
58
59 /* -----------------------------------------------------------------------------
60 * DPSUB Configuration
61 */
62
63 /**
64 * zynqmp_dpsub_audio_enabled - If the audio is enabled
65 * @dpsub: DisplayPort subsystem
66 *
67 * Return if the audio is enabled depending on the audio clock.
68 *
69 * Return: true if audio is enabled, or false.
70 */
zynqmp_dpsub_audio_enabled(struct zynqmp_dpsub * dpsub)71 bool zynqmp_dpsub_audio_enabled(struct zynqmp_dpsub *dpsub)
72 {
73 return !!dpsub->aud_clk;
74 }
75
76 /**
77 * zynqmp_dpsub_get_audio_clk_rate - Get the current audio clock rate
78 * @dpsub: DisplayPort subsystem
79 *
80 * Return: the current audio clock rate.
81 */
zynqmp_dpsub_get_audio_clk_rate(struct zynqmp_dpsub * dpsub)82 unsigned int zynqmp_dpsub_get_audio_clk_rate(struct zynqmp_dpsub *dpsub)
83 {
84 if (zynqmp_dpsub_audio_enabled(dpsub))
85 return 0;
86 return clk_get_rate(dpsub->aud_clk);
87 }
88
89 /* -----------------------------------------------------------------------------
90 * Probe & Remove
91 */
92
zynqmp_dpsub_init_clocks(struct zynqmp_dpsub * dpsub)93 static int zynqmp_dpsub_init_clocks(struct zynqmp_dpsub *dpsub)
94 {
95 int ret;
96
97 dpsub->apb_clk = devm_clk_get(dpsub->dev, "dp_apb_clk");
98 if (IS_ERR(dpsub->apb_clk))
99 return PTR_ERR(dpsub->apb_clk);
100
101 ret = clk_prepare_enable(dpsub->apb_clk);
102 if (ret) {
103 dev_err(dpsub->dev, "failed to enable the APB clock\n");
104 return ret;
105 }
106
107 /*
108 * Try the live PL video clock, and fall back to the PS clock if the
109 * live PL video clock isn't valid.
110 */
111 dpsub->vid_clk = devm_clk_get(dpsub->dev, "dp_live_video_in_clk");
112 if (!IS_ERR(dpsub->vid_clk))
113 dpsub->vid_clk_from_ps = false;
114 else if (PTR_ERR(dpsub->vid_clk) == -EPROBE_DEFER)
115 return PTR_ERR(dpsub->vid_clk);
116
117 if (IS_ERR_OR_NULL(dpsub->vid_clk)) {
118 dpsub->vid_clk = devm_clk_get(dpsub->dev, "dp_vtc_pixel_clk_in");
119 if (IS_ERR(dpsub->vid_clk)) {
120 dev_err(dpsub->dev, "failed to init any video clock\n");
121 return PTR_ERR(dpsub->vid_clk);
122 }
123 dpsub->vid_clk_from_ps = true;
124 }
125
126 /*
127 * Try the live PL audio clock, and fall back to the PS clock if the
128 * live PL audio clock isn't valid. Missing audio clock disables audio
129 * but isn't an error.
130 */
131 dpsub->aud_clk = devm_clk_get(dpsub->dev, "dp_live_audio_aclk");
132 if (!IS_ERR(dpsub->aud_clk)) {
133 dpsub->aud_clk_from_ps = false;
134 return 0;
135 }
136
137 dpsub->aud_clk = devm_clk_get(dpsub->dev, "dp_aud_clk");
138 if (!IS_ERR(dpsub->aud_clk)) {
139 dpsub->aud_clk_from_ps = true;
140 return 0;
141 }
142
143 dev_info(dpsub->dev, "audio disabled due to missing clock\n");
144 return 0;
145 }
146
zynqmp_dpsub_parse_dt(struct zynqmp_dpsub * dpsub)147 static int zynqmp_dpsub_parse_dt(struct zynqmp_dpsub *dpsub)
148 {
149 struct device_node *np;
150 unsigned int i;
151
152 /*
153 * For backward compatibility with old device trees that don't contain
154 * ports, consider that only the DP output port is connected if no
155 * ports child no exists.
156 */
157 np = of_get_child_by_name(dpsub->dev->of_node, "ports");
158 of_node_put(np);
159 if (!np) {
160 dev_warn(dpsub->dev, "missing ports, update DT bindings\n");
161 dpsub->connected_ports = BIT(ZYNQMP_DPSUB_PORT_OUT_DP);
162 dpsub->dma_enabled = true;
163 return 0;
164 }
165
166 /* Check which ports are connected. */
167 for (i = 0; i < ZYNQMP_DPSUB_NUM_PORTS; ++i) {
168 struct device_node *np;
169
170 np = of_graph_get_remote_node(dpsub->dev->of_node, i, -1);
171 if (np) {
172 dpsub->connected_ports |= BIT(i);
173 of_node_put(np);
174 }
175 }
176
177 /* Sanity checks. */
178 if ((dpsub->connected_ports & BIT(ZYNQMP_DPSUB_PORT_LIVE_VIDEO)) &&
179 (dpsub->connected_ports & BIT(ZYNQMP_DPSUB_PORT_LIVE_GFX))) {
180 dev_err(dpsub->dev, "only one live video input is supported\n");
181 return -EINVAL;
182 }
183
184 if ((dpsub->connected_ports & BIT(ZYNQMP_DPSUB_PORT_LIVE_VIDEO)) ||
185 (dpsub->connected_ports & BIT(ZYNQMP_DPSUB_PORT_LIVE_GFX))) {
186 if (dpsub->vid_clk_from_ps) {
187 dev_err(dpsub->dev,
188 "live video input requires PL clock\n");
189 return -EINVAL;
190 }
191 } else {
192 dpsub->dma_enabled = true;
193 }
194
195 if (dpsub->connected_ports & BIT(ZYNQMP_DPSUB_PORT_LIVE_AUDIO))
196 dev_warn(dpsub->dev, "live audio unsupported, ignoring\n");
197
198 if ((dpsub->connected_ports & BIT(ZYNQMP_DPSUB_PORT_OUT_VIDEO)) ||
199 (dpsub->connected_ports & BIT(ZYNQMP_DPSUB_PORT_OUT_AUDIO)))
200 dev_warn(dpsub->dev, "output to PL unsupported, ignoring\n");
201
202 if (!(dpsub->connected_ports & BIT(ZYNQMP_DPSUB_PORT_OUT_DP))) {
203 dev_err(dpsub->dev, "DP output port not connected\n");
204 return -EINVAL;
205 }
206
207 return 0;
208 }
209
zynqmp_dpsub_release(struct zynqmp_dpsub * dpsub)210 void zynqmp_dpsub_release(struct zynqmp_dpsub *dpsub)
211 {
212 kfree(dpsub->disp);
213 kfree(dpsub->dp);
214 kfree(dpsub);
215 }
216
zynqmp_dpsub_probe(struct platform_device * pdev)217 static int zynqmp_dpsub_probe(struct platform_device *pdev)
218 {
219 struct zynqmp_dpsub *dpsub;
220 int ret;
221
222 /* Allocate private data. */
223 dpsub = kzalloc(sizeof(*dpsub), GFP_KERNEL);
224 if (!dpsub)
225 return -ENOMEM;
226
227 dpsub->dev = &pdev->dev;
228 platform_set_drvdata(pdev, dpsub);
229
230 ret = dma_set_mask(dpsub->dev, DMA_BIT_MASK(ZYNQMP_DISP_MAX_DMA_BIT));
231 if (ret)
232 return ret;
233
234 /* Try the reserved memory. Proceed if there's none. */
235 of_reserved_mem_device_init(&pdev->dev);
236
237 ret = zynqmp_dpsub_init_clocks(dpsub);
238 if (ret < 0)
239 goto err_mem;
240
241 ret = zynqmp_dpsub_parse_dt(dpsub);
242 if (ret < 0)
243 goto err_mem;
244
245 pm_runtime_enable(&pdev->dev);
246
247 /*
248 * DP should be probed first so that the zynqmp_disp can set the output
249 * format accordingly.
250 */
251 ret = zynqmp_dp_probe(dpsub);
252 if (ret)
253 goto err_pm;
254
255 ret = zynqmp_disp_probe(dpsub);
256 if (ret)
257 goto err_dp;
258
259 drm_bridge_add(dpsub->bridge);
260
261 if (dpsub->dma_enabled) {
262 ret = zynqmp_dpsub_drm_init(dpsub);
263 if (ret)
264 goto err_disp;
265 }
266
267 dev_info(&pdev->dev, "ZynqMP DisplayPort Subsystem driver probed");
268
269 return 0;
270
271 err_disp:
272 drm_bridge_remove(dpsub->bridge);
273 zynqmp_disp_remove(dpsub);
274 err_dp:
275 zynqmp_dp_remove(dpsub);
276 err_pm:
277 pm_runtime_disable(&pdev->dev);
278 clk_disable_unprepare(dpsub->apb_clk);
279 err_mem:
280 of_reserved_mem_device_release(&pdev->dev);
281 if (!dpsub->drm)
282 zynqmp_dpsub_release(dpsub);
283 return ret;
284 }
285
zynqmp_dpsub_remove(struct platform_device * pdev)286 static void zynqmp_dpsub_remove(struct platform_device *pdev)
287 {
288 struct zynqmp_dpsub *dpsub = platform_get_drvdata(pdev);
289
290 if (dpsub->drm)
291 zynqmp_dpsub_drm_cleanup(dpsub);
292
293 drm_bridge_remove(dpsub->bridge);
294 zynqmp_disp_remove(dpsub);
295 zynqmp_dp_remove(dpsub);
296
297 pm_runtime_disable(&pdev->dev);
298 clk_disable_unprepare(dpsub->apb_clk);
299 of_reserved_mem_device_release(&pdev->dev);
300
301 if (!dpsub->drm)
302 zynqmp_dpsub_release(dpsub);
303 }
304
zynqmp_dpsub_shutdown(struct platform_device * pdev)305 static void zynqmp_dpsub_shutdown(struct platform_device *pdev)
306 {
307 struct zynqmp_dpsub *dpsub = platform_get_drvdata(pdev);
308
309 if (!dpsub->drm)
310 return;
311
312 drm_atomic_helper_shutdown(&dpsub->drm->dev);
313 }
314
315 static const struct of_device_id zynqmp_dpsub_of_match[] = {
316 { .compatible = "xlnx,zynqmp-dpsub-1.7", },
317 { /* end of table */ },
318 };
319 MODULE_DEVICE_TABLE(of, zynqmp_dpsub_of_match);
320
321 static struct platform_driver zynqmp_dpsub_driver = {
322 .probe = zynqmp_dpsub_probe,
323 .remove = zynqmp_dpsub_remove,
324 .shutdown = zynqmp_dpsub_shutdown,
325 .driver = {
326 .name = "zynqmp-dpsub",
327 .pm = &zynqmp_dpsub_pm_ops,
328 .of_match_table = zynqmp_dpsub_of_match,
329 },
330 };
331
332 drm_module_platform_driver(zynqmp_dpsub_driver);
333
334 MODULE_AUTHOR("Xilinx, Inc.");
335 MODULE_DESCRIPTION("ZynqMP DP Subsystem Driver");
336 MODULE_LICENSE("GPL v2");
337