drivers/gpu/drm/xlnx/zynqmp_dpsub.c

   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 <[email protected]>
   9  * - Laurent Pinchart <[email protected]>
  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
  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
  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  */
  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  */
  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
  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
 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
 210 void zynqmp_dpsub_release(struct zynqmp_dpsub *dpsub)
 211 {
 212         kfree(dpsub->disp);
 213         kfree(dpsub->dp);
 214         kfree(dpsub);
 215 }
 216
 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         if (dpsub->dma_enabled) {
 260                 ret = zynqmp_dpsub_drm_init(dpsub);
 261                 if (ret)
 262                         goto err_disp;
 263         } else {
 264                 drm_bridge_add(dpsub->bridge);
 265         }
 266
 267         dev_info(&pdev->dev, "ZynqMP DisplayPort Subsystem driver probed");
 268
 269         return 0;
 270
 271 err_disp:
 272         zynqmp_disp_remove(dpsub);
 273 err_dp:
 274         zynqmp_dp_remove(dpsub);
 275 err_pm:
 276         pm_runtime_disable(&pdev->dev);
 277         clk_disable_unprepare(dpsub->apb_clk);
 278 err_mem:
 279         of_reserved_mem_device_release(&pdev->dev);
 280         if (!dpsub->drm)
 281                 zynqmp_dpsub_release(dpsub);
 282         return ret;
 283 }
 284
 285 static 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         else
 292                 drm_bridge_remove(dpsub->bridge);
 293
 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
 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_new             = 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");