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
 35static 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
 45static 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
 55static 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 */
 71bool 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 */
 82unsigned 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
 93static 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
147static 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
210void zynqmp_dpsub_release(struct zynqmp_dpsub *dpsub)
211{
212	kfree(dpsub->disp);
213	kfree(dpsub->dp);
214	kfree(dpsub);
215}
216
217static 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
271err_disp:
272	zynqmp_disp_remove(dpsub);
273err_dp:
274	zynqmp_dp_remove(dpsub);
275err_pm:
276	pm_runtime_disable(&pdev->dev);
277	clk_disable_unprepare(dpsub->apb_clk);
278err_mem:
279	of_reserved_mem_device_release(&pdev->dev);
280	if (!dpsub->drm)
281		zynqmp_dpsub_release(dpsub);
282	return ret;
283}
284
285static void zynqmp_dpsub_remove(struct platform_device *pdev)
286{
287	struct zynqmp_dpsub *dpsub = platform_get_drvdata(pdev);
288
289	if (dpsub->drm)
290		zynqmp_dpsub_drm_cleanup(dpsub);
291
292	drm_bridge_remove(dpsub->bridge);
293	zynqmp_disp_remove(dpsub);
294	zynqmp_dp_remove(dpsub);
295
296	pm_runtime_disable(&pdev->dev);
297	clk_disable_unprepare(dpsub->apb_clk);
298	of_reserved_mem_device_release(&pdev->dev);
299
300	if (!dpsub->drm)
301		zynqmp_dpsub_release(dpsub);
302}
303
304static void zynqmp_dpsub_shutdown(struct platform_device *pdev)
305{
306	struct zynqmp_dpsub *dpsub = platform_get_drvdata(pdev);
307
308	if (!dpsub->drm)
309		return;
310
311	drm_atomic_helper_shutdown(&dpsub->drm->dev);
312}
313
314static const struct of_device_id zynqmp_dpsub_of_match[] = {
315	{ .compatible = "xlnx,zynqmp-dpsub-1.7", },
316	{ /* end of table */ },
317};
318MODULE_DEVICE_TABLE(of, zynqmp_dpsub_of_match);
319
320static struct platform_driver zynqmp_dpsub_driver = {
321	.probe			= zynqmp_dpsub_probe,
322	.remove_new		= zynqmp_dpsub_remove,
323	.shutdown		= zynqmp_dpsub_shutdown,
324	.driver			= {
325		.name		= "zynqmp-dpsub",
326		.pm		= &zynqmp_dpsub_pm_ops,
327		.of_match_table	= zynqmp_dpsub_of_match,
328	},
329};
330
331drm_module_platform_driver(zynqmp_dpsub_driver);
332
333MODULE_AUTHOR("Xilinx, Inc.");
334MODULE_DESCRIPTION("ZynqMP DP Subsystem Driver");
335MODULE_LICENSE("GPL v2");