drivers/gpu/drm/tve200/tve200_drv.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
   4  * Parts of this file were based on sources as follows:
   5  *
   6  * Copyright (C) 2006-2008 Intel Corporation
   7  * Copyright (C) 2007 Amos Lee <amos_lee@storlinksemi.com>
   8  * Copyright (C) 2007 Dave Airlie <airlied@linux.ie>
   9  * Copyright (C) 2011 Texas Instruments
  10  * Copyright (C) 2017 Eric Anholt
  11  */
  12
  13 /**
  14  * DOC: Faraday TV Encoder TVE200 DRM Driver
  15  *
  16  * The Faraday TV Encoder TVE200 is also known as the Gemini TV Interface
  17  * Controller (TVC) and is found in the Gemini Chipset from Storlink
  18  * Semiconductor (later Storm Semiconductor, later Cortina Systems)
  19  * but also in the Grain Media GM8180 chipset. On the Gemini the module
  20  * is connected to 8 data lines and a single clock line, comprising an
  21  * 8-bit BT.656 interface.
  22  *
  23  * This is a very basic YUV display driver. The datasheet specifies that
  24  * it supports the ITU BT.656 standard. It requires a 27 MHz clock which is
  25  * the hallmark of any TV encoder supporting both PAL and NTSC.
  26  *
  27  * This driver exposes a standard KMS interface for this TV encoder.
  28  */
  29
  30 #include <linux/clk.h>
  31 #include <linux/dma-buf.h>
  32 #include <linux/irq.h>
  33 #include <linux/io.h>
  34 #include <linux/module.h>
  35 #include <linux/platform_device.h>
  36 #include <linux/shmem_fs.h>
  37 #include <linux/slab.h>
  38 #include <linux/version.h>
  39
  40 #include <drm/drm_atomic_helper.h>
  41 #include <drm/drm_bridge.h>
  42 #include <drm/drm_drv.h>
  43 #include <drm/drm_fb_cma_helper.h>
  44 #include <drm/drm_fb_helper.h>
  45 #include <drm/drm_gem_cma_helper.h>
  46 #include <drm/drm_gem_framebuffer_helper.h>
  47 #include <drm/drm_of.h>
  48 #include <drm/drm_panel.h>
  49 #include <drm/drm_probe_helper.h>
  50 #include <drm/drm_vblank.h>
  51
  52 #include "tve200_drm.h"
  53
  54 #define DRIVER_DESC      "DRM module for Faraday TVE200"
  55
  56 static const struct drm_mode_config_funcs mode_config_funcs = {
  57         .fb_create = drm_gem_fb_create,
  58         .atomic_check = drm_atomic_helper_check,
  59         .atomic_commit = drm_atomic_helper_commit,
  60 };
  61
  62 static int tve200_modeset_init(struct drm_device *dev)
  63 {
  64         struct drm_mode_config *mode_config;
  65         struct tve200_drm_dev_private *priv = dev->dev_private;
  66         struct drm_panel *panel;
  67         struct drm_bridge *bridge;
  68         int ret = 0;
  69
  70         drm_mode_config_init(dev);
  71         mode_config = &dev->mode_config;
  72         mode_config->funcs = &mode_config_funcs;
  73         mode_config->min_width = 352;
  74         mode_config->max_width = 720;
  75         mode_config->min_height = 240;
  76         mode_config->max_height = 576;
  77
  78         ret = drm_of_find_panel_or_bridge(dev->dev->of_node,
  79                                           0, 0, &panel, &bridge);
  80         if (ret && ret != -ENODEV)
  81                 return ret;
  82         if (panel) {
  83                 bridge = drm_panel_bridge_add_typed(panel,
  84                                                     DRM_MODE_CONNECTOR_Unknown);
  85                 if (IS_ERR(bridge)) {
  86                         ret = PTR_ERR(bridge);
  87                         goto out_bridge;
  88                 }
  89         } else {
  90                 /*
  91                  * TODO: when we are using a different bridge than a panel
  92                  * (such as a dumb VGA connector) we need to devise a different
  93                  * method to get the connector out of the bridge.
  94                  */
  95                 dev_err(dev->dev, "the bridge is not a panel\n");
  96                 goto out_bridge;
  97         }
  98
  99         ret = tve200_display_init(dev);
 100         if (ret) {
 101                 dev_err(dev->dev, "failed to init display\n");
 102                 goto out_bridge;
 103         }
 104
 105         ret = drm_simple_display_pipe_attach_bridge(&priv->pipe,
 106                                                     bridge);
 107         if (ret) {
 108                 dev_err(dev->dev, "failed to attach bridge\n");
 109                 goto out_bridge;
 110         }
 111
 112         priv->panel = panel;
 113         priv->connector = drm_panel_bridge_connector(bridge);
 114         priv->bridge = bridge;
 115
 116         dev_info(dev->dev, "attached to panel %s\n",
 117                  dev_name(panel->dev));
 118
 119         ret = drm_vblank_init(dev, 1);
 120         if (ret) {
 121                 dev_err(dev->dev, "failed to init vblank\n");
 122                 goto out_bridge;
 123         }
 124
 125         drm_mode_config_reset(dev);
 126         drm_kms_helper_poll_init(dev);
 127
 128         goto finish;
 129
 130 out_bridge:
 131         if (panel)
 132                 drm_panel_bridge_remove(bridge);
 133         drm_mode_config_cleanup(dev);
 134 finish:
 135         return ret;
 136 }
 137
 138 DEFINE_DRM_GEM_CMA_FOPS(drm_fops);
 139
 140 static const struct drm_driver tve200_drm_driver = {
 141         .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
 142         .ioctls = NULL,
 143         .fops = &drm_fops,
 144         .name = "tve200",
 145         .desc = DRIVER_DESC,
 146         .date = "20170703",
 147         .major = 1,
 148         .minor = 0,
 149         .patchlevel = 0,
 150         DRM_GEM_CMA_DRIVER_OPS,
 151 };
 152
 153 static int tve200_probe(struct platform_device *pdev)
 154 {
 155         struct device *dev = &pdev->dev;
 156         struct tve200_drm_dev_private *priv;
 157         struct drm_device *drm;
 158         struct resource *res;
 159         int irq;
 160         int ret;
 161
 162         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 163         if (!priv)
 164                 return -ENOMEM;
 165
 166         drm = drm_dev_alloc(&tve200_drm_driver, dev);
 167         if (IS_ERR(drm))
 168                 return PTR_ERR(drm);
 169         platform_set_drvdata(pdev, drm);
 170         priv->drm = drm;
 171         drm->dev_private = priv;
 172
 173         /* Clock the silicon so we can access the registers */
 174         priv->pclk = devm_clk_get(dev, "PCLK");
 175         if (IS_ERR(priv->pclk)) {
 176                 dev_err(dev, "unable to get PCLK\n");
 177                 ret = PTR_ERR(priv->pclk);
 178                 goto dev_unref;
 179         }
 180         ret = clk_prepare_enable(priv->pclk);
 181         if (ret) {
 182                 dev_err(dev, "failed to enable PCLK\n");
 183                 goto dev_unref;
 184         }
 185
 186         /* This clock is for the pixels (27MHz) */
 187         priv->clk = devm_clk_get(dev, "TVE");
 188         if (IS_ERR(priv->clk)) {
 189                 dev_err(dev, "unable to get TVE clock\n");
 190                 ret = PTR_ERR(priv->clk);
 191                 goto clk_disable;
 192         }
 193
 194         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 195         priv->regs = devm_ioremap_resource(dev, res);
 196         if (IS_ERR(priv->regs)) {
 197                 dev_err(dev, "%s failed mmio\n", __func__);
 198                 ret = -EINVAL;
 199                 goto clk_disable;
 200         }
 201
 202         irq = platform_get_irq(pdev, 0);
 203         if (irq < 0) {
 204                 ret = irq;
 205                 goto clk_disable;
 206         }
 207
 208         /* turn off interrupts before requesting the irq */
 209         writel(0, priv->regs + TVE200_INT_EN);
 210
 211         ret = devm_request_irq(dev, irq, tve200_irq, 0, "tve200", priv);
 212         if (ret) {
 213                 dev_err(dev, "failed to request irq %d\n", ret);
 214                 goto clk_disable;
 215         }
 216
 217         ret = tve200_modeset_init(drm);
 218         if (ret)
 219                 goto clk_disable;
 220
 221         ret = drm_dev_register(drm, 0);
 222         if (ret < 0)
 223                 goto clk_disable;
 224
 225         /*
 226          * Passing in 16 here will make the RGB565 mode the default
 227          * Passing in 32 will use XRGB8888 mode
 228          */
 229         drm_fbdev_generic_setup(drm, 16);
 230
 231         return 0;
 232
 233 clk_disable:
 234         clk_disable_unprepare(priv->pclk);
 235 dev_unref:
 236         drm_dev_put(drm);
 237         return ret;
 238 }
 239
 240 static int tve200_remove(struct platform_device *pdev)
 241 {
 242         struct drm_device *drm = platform_get_drvdata(pdev);
 243         struct tve200_drm_dev_private *priv = drm->dev_private;
 244
 245         drm_dev_unregister(drm);
 246         if (priv->panel)
 247                 drm_panel_bridge_remove(priv->bridge);
 248         drm_mode_config_cleanup(drm);
 249         clk_disable_unprepare(priv->pclk);
 250         drm_dev_put(drm);
 251
 252         return 0;
 253 }
 254
 255 static const struct of_device_id tve200_of_match[] = {
 256         {
 257                 .compatible = "faraday,tve200",
 258         },
 259         {},
 260 };
 261
 262 static struct platform_driver tve200_driver = {
 263         .driver = {
 264                 .name           = "tve200",
 265                 .of_match_table = of_match_ptr(tve200_of_match),
 266         },
 267         .probe = tve200_probe,
 268         .remove = tve200_remove,
 269 };
 270 module_platform_driver(tve200_driver);
 271
 272 MODULE_DESCRIPTION(DRIVER_DESC);
 273 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
 274 MODULE_LICENSE("GPL");