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/of.h> 36 #include <linux/platform_device.h> 37 #include <linux/shmem_fs.h> 38 #include <linux/slab.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_fbdev_generic.h> 44 #include <drm/drm_gem_dma_helper.h> 45 #include <drm/drm_gem_framebuffer_helper.h> 46 #include <drm/drm_module.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; 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 ret = -EINVAL; 97 goto out_bridge; 98 } 99 100 ret = tve200_display_init(dev); 101 if (ret) { 102 dev_err(dev->dev, "failed to init display\n"); 103 goto out_bridge; 104 } 105 106 ret = drm_simple_display_pipe_attach_bridge(&priv->pipe, 107 bridge); 108 if (ret) { 109 dev_err(dev->dev, "failed to attach bridge\n"); 110 goto out_bridge; 111 } 112 113 priv->panel = panel; 114 priv->connector = drm_panel_bridge_connector(bridge); 115 priv->bridge = bridge; 116 117 dev_info(dev->dev, "attached to panel %s\n", 118 dev_name(panel->dev)); 119 120 ret = drm_vblank_init(dev, 1); 121 if (ret) { 122 dev_err(dev->dev, "failed to init vblank\n"); 123 goto out_bridge; 124 } 125 126 drm_mode_config_reset(dev); 127 drm_kms_helper_poll_init(dev); 128 129 goto finish; 130 131 out_bridge: 132 if (panel) 133 drm_panel_bridge_remove(bridge); 134 drm_mode_config_cleanup(dev); 135 finish: 136 return ret; 137 } 138 139 DEFINE_DRM_GEM_DMA_FOPS(drm_fops); 140 141 static const struct drm_driver tve200_drm_driver = { 142 .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC, 143 .ioctls = NULL, 144 .fops = &drm_fops, 145 .name = "tve200", 146 .desc = DRIVER_DESC, 147 .date = "20170703", 148 .major = 1, 149 .minor = 0, 150 .patchlevel = 0, 151 DRM_GEM_DMA_DRIVER_OPS, 152 }; 153 154 static int tve200_probe(struct platform_device *pdev) 155 { 156 struct device *dev = &pdev->dev; 157 struct tve200_drm_dev_private *priv; 158 struct drm_device *drm; 159 struct resource *res; 160 int irq; 161 int ret; 162 163 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 164 if (!priv) 165 return -ENOMEM; 166 167 drm = drm_dev_alloc(&tve200_drm_driver, dev); 168 if (IS_ERR(drm)) 169 return PTR_ERR(drm); 170 platform_set_drvdata(pdev, drm); 171 priv->drm = drm; 172 drm->dev_private = priv; 173 174 /* Clock the silicon so we can access the registers */ 175 priv->pclk = devm_clk_get(dev, "PCLK"); 176 if (IS_ERR(priv->pclk)) { 177 dev_err(dev, "unable to get PCLK\n"); 178 ret = PTR_ERR(priv->pclk); 179 goto dev_unref; 180 } 181 ret = clk_prepare_enable(priv->pclk); 182 if (ret) { 183 dev_err(dev, "failed to enable PCLK\n"); 184 goto dev_unref; 185 } 186 187 /* This clock is for the pixels (27MHz) */ 188 priv->clk = devm_clk_get(dev, "TVE"); 189 if (IS_ERR(priv->clk)) { 190 dev_err(dev, "unable to get TVE clock\n"); 191 ret = PTR_ERR(priv->clk); 192 goto clk_disable; 193 } 194 195 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 196 priv->regs = devm_ioremap_resource(dev, res); 197 if (IS_ERR(priv->regs)) { 198 dev_err(dev, "%s failed mmio\n", __func__); 199 ret = -EINVAL; 200 goto clk_disable; 201 } 202 203 irq = platform_get_irq(pdev, 0); 204 if (irq < 0) { 205 ret = irq; 206 goto clk_disable; 207 } 208 209 /* turn off interrupts before requesting the irq */ 210 writel(0, priv->regs + TVE200_INT_EN); 211 212 ret = devm_request_irq(dev, irq, tve200_irq, 0, "tve200", priv); 213 if (ret) { 214 dev_err(dev, "failed to request irq %d\n", ret); 215 goto clk_disable; 216 } 217 218 ret = tve200_modeset_init(drm); 219 if (ret) 220 goto clk_disable; 221 222 ret = drm_dev_register(drm, 0); 223 if (ret < 0) 224 goto clk_disable; 225 226 /* 227 * Passing in 16 here will make the RGB565 mode the default 228 * Passing in 32 will use XRGB8888 mode 229 */ 230 drm_fbdev_generic_setup(drm, 16); 231 232 return 0; 233 234 clk_disable: 235 clk_disable_unprepare(priv->pclk); 236 dev_unref: 237 drm_dev_put(drm); 238 return ret; 239 } 240 241 static int tve200_remove(struct platform_device *pdev) 242 { 243 struct drm_device *drm = platform_get_drvdata(pdev); 244 struct tve200_drm_dev_private *priv = drm->dev_private; 245 246 drm_dev_unregister(drm); 247 if (priv->panel) 248 drm_panel_bridge_remove(priv->bridge); 249 drm_mode_config_cleanup(drm); 250 clk_disable_unprepare(priv->pclk); 251 drm_dev_put(drm); 252 253 return 0; 254 } 255 256 static const struct of_device_id tve200_of_match[] = { 257 { 258 .compatible = "faraday,tve200", 259 }, 260 {}, 261 }; 262 263 static struct platform_driver tve200_driver = { 264 .driver = { 265 .name = "tve200", 266 .of_match_table = of_match_ptr(tve200_of_match), 267 }, 268 .probe = tve200_probe, 269 .remove = tve200_remove, 270 }; 271 drm_module_platform_driver(tve200_driver); 272 273 MODULE_DESCRIPTION(DRIVER_DESC); 274 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>"); 275 MODULE_LICENSE("GPL"); 276