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"); 274