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
  39 #include <drm/drm_atomic_helper.h>
  40 #include <drm/drm_bridge.h>
  41 #include <drm/drm_drv.h>
  42 #include <drm/drm_fb_cma_helper.h>
  43 #include <drm/drm_fb_helper.h>
  44 #include <drm/drm_gem_cma_helper.h>
  45 #include <drm/drm_gem_framebuffer_helper.h>
  46 #include <drm/drm_of.h>
  47 #include <drm/drm_panel.h>
  48 #include <drm/drm_probe_helper.h>
  49 #include <drm/drm_vblank.h>
  50
  51 #include "tve200_drm.h"
  52
  53 #define DRIVER_DESC      "DRM module for Faraday TVE200"
  54
  55 static const struct drm_mode_config_funcs mode_config_funcs = {
  56         .fb_create = drm_gem_fb_create,
  57         .atomic_check = drm_atomic_helper_check,
  58         .atomic_commit = drm_atomic_helper_commit,
  59 };
  60
  61 static int tve200_modeset_init(struct drm_device *dev)
  62 {
  63         struct drm_mode_config *mode_config;
  64         struct tve200_drm_dev_private *priv = dev->dev_private;
  65         struct drm_panel *panel;
  66         struct drm_bridge *bridge;
  67         int ret = 0;
  68
  69         drm_mode_config_init(dev);
  70         mode_config = &dev->mode_config;
  71         mode_config->funcs = &mode_config_funcs;
  72         mode_config->min_width = 352;
  73         mode_config->max_width = 720;
  74         mode_config->min_height = 240;
  75         mode_config->max_height = 576;
  76
  77         ret = drm_of_find_panel_or_bridge(dev->dev->of_node,
  78                                           0, 0, &panel, &bridge);
  79         if (ret && ret != -ENODEV)
  80                 return ret;
  81         if (panel) {
  82                 bridge = drm_panel_bridge_add_typed(panel,
  83                                                     DRM_MODE_CONNECTOR_Unknown);
  84                 if (IS_ERR(bridge)) {
  85                         ret = PTR_ERR(bridge);
  86                         goto out_bridge;
  87                 }
  88         } else {
  89                 /*
  90                  * TODO: when we are using a different bridge than a panel
  91                  * (such as a dumb VGA connector) we need to devise a different
  92                  * method to get the connector out of the bridge.
  93                  */
  94                 dev_err(dev->dev, "the bridge is not a panel\n");
  95                 goto out_bridge;
  96         }
  97
  98         ret = tve200_display_init(dev);
  99         if (ret) {
 100                 dev_err(dev->dev, "failed to init display\n");
 101                 goto out_bridge;
 102         }
 103
 104         ret = drm_simple_display_pipe_attach_bridge(&priv->pipe,
 105                                                     bridge);
 106         if (ret) {
 107                 dev_err(dev->dev, "failed to attach bridge\n");
 108                 goto out_bridge;
 109         }
 110
 111         priv->panel = panel;
 112         priv->connector = drm_panel_bridge_connector(bridge);
 113         priv->bridge = bridge;
 114
 115         dev_info(dev->dev, "attached to panel %s\n",
 116                  dev_name(panel->dev));
 117
 118         ret = drm_vblank_init(dev, 1);
 119         if (ret) {
 120                 dev_err(dev->dev, "failed to init vblank\n");
 121                 goto out_bridge;
 122         }
 123
 124         drm_mode_config_reset(dev);
 125         drm_kms_helper_poll_init(dev);
 126
 127         goto finish;
 128
 129 out_bridge:
 130         if (panel)
 131                 drm_panel_bridge_remove(bridge);
 132         drm_mode_config_cleanup(dev);
 133 finish:
 134         return ret;
 135 }
 136
 137 DEFINE_DRM_GEM_CMA_FOPS(drm_fops);
 138
 139 static const struct drm_driver tve200_drm_driver = {
 140         .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
 141         .ioctls = NULL,
 142         .fops = &drm_fops,
 143         .name = "tve200",
 144         .desc = DRIVER_DESC,
 145         .date = "20170703",
 146         .major = 1,
 147         .minor = 0,
 148         .patchlevel = 0,
 149         DRM_GEM_CMA_DRIVER_OPS,
 150 };
 151
 152 static int tve200_probe(struct platform_device *pdev)
 153 {
 154         struct device *dev = &pdev->dev;
 155         struct tve200_drm_dev_private *priv;
 156         struct drm_device *drm;
 157         struct resource *res;
 158         int irq;
 159         int ret;
 160
 161         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 162         if (!priv)
 163                 return -ENOMEM;
 164
 165         drm = drm_dev_alloc(&tve200_drm_driver, dev);
 166         if (IS_ERR(drm))
 167                 return PTR_ERR(drm);
 168         platform_set_drvdata(pdev, drm);
 169         priv->drm = drm;
 170         drm->dev_private = priv;
 171
 172         /* Clock the silicon so we can access the registers */
 173         priv->pclk = devm_clk_get(dev, "PCLK");
 174         if (IS_ERR(priv->pclk)) {
 175                 dev_err(dev, "unable to get PCLK\n");
 176                 ret = PTR_ERR(priv->pclk);
 177                 goto dev_unref;
 178         }
 179         ret = clk_prepare_enable(priv->pclk);
 180         if (ret) {
 181                 dev_err(dev, "failed to enable PCLK\n");
 182                 goto dev_unref;
 183         }
 184
 185         /* This clock is for the pixels (27MHz) */
 186         priv->clk = devm_clk_get(dev, "TVE");
 187         if (IS_ERR(priv->clk)) {
 188                 dev_err(dev, "unable to get TVE clock\n");
 189                 ret = PTR_ERR(priv->clk);
 190                 goto clk_disable;
 191         }
 192
 193         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 194         priv->regs = devm_ioremap_resource(dev, res);
 195         if (IS_ERR(priv->regs)) {
 196                 dev_err(dev, "%s failed mmio\n", __func__);
 197                 ret = -EINVAL;
 198                 goto clk_disable;
 199         }
 200
 201         irq = platform_get_irq(pdev, 0);
 202         if (irq < 0) {
 203                 ret = irq;
 204                 goto clk_disable;
 205         }
 206
 207         /* turn off interrupts before requesting the irq */
 208         writel(0, priv->regs + TVE200_INT_EN);
 209
 210         ret = devm_request_irq(dev, irq, tve200_irq, 0, "tve200", priv);
 211         if (ret) {
 212                 dev_err(dev, "failed to request irq %d\n", ret);
 213                 goto clk_disable;
 214         }
 215
 216         ret = tve200_modeset_init(drm);
 217         if (ret)
 218                 goto clk_disable;
 219
 220         ret = drm_dev_register(drm, 0);
 221         if (ret < 0)
 222                 goto clk_disable;
 223
 224         /*
 225          * Passing in 16 here will make the RGB565 mode the default
 226          * Passing in 32 will use XRGB8888 mode
 227          */
 228         drm_fbdev_generic_setup(drm, 16);
 229
 230         return 0;
 231
 232 clk_disable:
 233         clk_disable_unprepare(priv->pclk);
 234 dev_unref:
 235         drm_dev_put(drm);
 236         return ret;
 237 }
 238
 239 static int tve200_remove(struct platform_device *pdev)
 240 {
 241         struct drm_device *drm = platform_get_drvdata(pdev);
 242         struct tve200_drm_dev_private *priv = drm->dev_private;
 243
 244         drm_dev_unregister(drm);
 245         if (priv->panel)
 246                 drm_panel_bridge_remove(priv->bridge);
 247         drm_mode_config_cleanup(drm);
 248         clk_disable_unprepare(priv->pclk);
 249         drm_dev_put(drm);
 250
 251         return 0;
 252 }
 253
 254 static const struct of_device_id tve200_of_match[] = {
 255         {
 256                 .compatible = "faraday,tve200",
 257         },
 258         {},
 259 };
 260
 261 static struct platform_driver tve200_driver = {
 262         .driver = {
 263                 .name           = "tve200",
 264                 .of_match_table = of_match_ptr(tve200_of_match),
 265         },
 266         .probe = tve200_probe,
 267         .remove = tve200_remove,
 268 };
 269 module_platform_driver(tve200_driver);
 270
 271 MODULE_DESCRIPTION(DRIVER_DESC);
 272 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
 273 MODULE_LICENSE("GPL");