drivers/gpu/drm/vkms/vkms_drv.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License as published by
   4  * the Free Software Foundation; either version 2 of the License, or
   5  * (at your option) any later version.
   6  */
   7
   8 /**
   9  * DOC: vkms (Virtual Kernel Modesetting)
  10  *
  11  * vkms is a software-only model of a kms driver that is useful for testing,
  12  * or for running X (or similar) on headless machines and be able to still
  13  * use the GPU. vkms aims to enable a virtual display without the need for
  14  * a hardware display capability.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <drm/drm_gem.h>
  19 #include <drm/drm_atomic_helper.h>
  20 #include <drm/drm_gem_framebuffer_helper.h>
  21 #include <drm/drm_fb_helper.h>
  22 #include <drm/drm_probe_helper.h>
  23 #include "vkms_drv.h"
  24
  25 #define DRIVER_NAME     "vkms"
  26 #define DRIVER_DESC     "Virtual Kernel Mode Setting"
  27 #define DRIVER_DATE     "20180514"
  28 #define DRIVER_MAJOR    1
  29 #define DRIVER_MINOR    0
  30
  31 static struct vkms_device *vkms_device;
  32
  33 bool enable_cursor;
  34 module_param_named(enable_cursor, enable_cursor, bool, 0444);
  35 MODULE_PARM_DESC(enable_cursor, "Enable/Disable cursor support");
  36
  37 static const struct file_operations vkms_driver_fops = {
  38         .owner          = THIS_MODULE,
  39         .open           = drm_open,
  40         .mmap           = drm_gem_mmap,
  41         .unlocked_ioctl = drm_ioctl,
  42         .compat_ioctl   = drm_compat_ioctl,
  43         .poll           = drm_poll,
  44         .read           = drm_read,
  45         .llseek         = no_llseek,
  46         .release        = drm_release,
  47 };
  48
  49 static const struct vm_operations_struct vkms_gem_vm_ops = {
  50         .fault = vkms_gem_fault,
  51         .open = drm_gem_vm_open,
  52         .close = drm_gem_vm_close,
  53 };
  54
  55 static void vkms_release(struct drm_device *dev)
  56 {
  57         struct vkms_device *vkms = container_of(dev, struct vkms_device, drm);
  58
  59         platform_device_unregister(vkms->platform);
  60         drm_atomic_helper_shutdown(&vkms->drm);
  61         drm_mode_config_cleanup(&vkms->drm);
  62         drm_dev_fini(&vkms->drm);
  63         destroy_workqueue(vkms->output.crc_workq);
  64 }
  65
  66 static struct drm_driver vkms_driver = {
  67         .driver_features        = DRIVER_MODESET | DRIVER_ATOMIC | DRIVER_GEM,
  68         .release                = vkms_release,
  69         .fops                   = &vkms_driver_fops,
  70         .dumb_create            = vkms_dumb_create,
  71         .gem_vm_ops             = &vkms_gem_vm_ops,
  72         .gem_free_object_unlocked = vkms_gem_free_object,
  73         .get_vblank_timestamp   = vkms_get_vblank_timestamp,
  74
  75         .name                   = DRIVER_NAME,
  76         .desc                   = DRIVER_DESC,
  77         .date                   = DRIVER_DATE,
  78         .major                  = DRIVER_MAJOR,
  79         .minor                  = DRIVER_MINOR,
  80 };
  81
  82 static const struct drm_mode_config_funcs vkms_mode_funcs = {
  83         .fb_create = drm_gem_fb_create,
  84         .atomic_check = drm_atomic_helper_check,
  85         .atomic_commit = drm_atomic_helper_commit,
  86 };
  87
  88 static int vkms_modeset_init(struct vkms_device *vkmsdev)
  89 {
  90         struct drm_device *dev = &vkmsdev->drm;
  91
  92         drm_mode_config_init(dev);
  93         dev->mode_config.funcs = &vkms_mode_funcs;
  94         dev->mode_config.min_width = XRES_MIN;
  95         dev->mode_config.min_height = YRES_MIN;
  96         dev->mode_config.max_width = XRES_MAX;
  97         dev->mode_config.max_height = YRES_MAX;
  98         dev->mode_config.preferred_depth = 24;
  99
 100         return vkms_output_init(vkmsdev);
 101 }
 102
 103 static int __init vkms_init(void)
 104 {
 105         int ret;
 106
 107         vkms_device = kzalloc(sizeof(*vkms_device), GFP_KERNEL);
 108         if (!vkms_device)
 109                 return -ENOMEM;
 110
 111         vkms_device->platform =
 112                 platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
 113         if (IS_ERR(vkms_device->platform)) {
 114                 ret = PTR_ERR(vkms_device->platform);
 115                 goto out_free;
 116         }
 117
 118         ret = drm_dev_init(&vkms_device->drm, &vkms_driver,
 119                            &vkms_device->platform->dev);
 120         if (ret)
 121                 goto out_unregister;
 122
 123         vkms_device->drm.irq_enabled = true;
 124
 125         ret = drm_vblank_init(&vkms_device->drm, 1);
 126         if (ret) {
 127                 DRM_ERROR("Failed to vblank\n");
 128                 goto out_fini;
 129         }
 130
 131         ret = vkms_modeset_init(vkms_device);
 132         if (ret)
 133                 goto out_fini;
 134
 135         ret = drm_dev_register(&vkms_device->drm, 0);
 136         if (ret)
 137                 goto out_fini;
 138
 139         return 0;
 140
 141 out_fini:
 142         drm_dev_fini(&vkms_device->drm);
 143
 144 out_unregister:
 145         platform_device_unregister(vkms_device->platform);
 146
 147 out_free:
 148         kfree(vkms_device);
 149         return ret;
 150 }
 151
 152 static void __exit vkms_exit(void)
 153 {
 154         if (!vkms_device) {
 155                 DRM_INFO("vkms_device is NULL.\n");
 156                 return;
 157         }
 158
 159         drm_dev_unregister(&vkms_device->drm);
 160         drm_dev_put(&vkms_device->drm);
 161
 162         kfree(vkms_device);
 163 }
 164
 165 module_init(vkms_init);
 166 module_exit(vkms_exit);
 167
 168 MODULE_AUTHOR("Haneen Mohammed <hamohammed.sa@gmail.com>");
 169 MODULE_AUTHOR("Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>");
 170 MODULE_DESCRIPTION(DRIVER_DESC);
 171 MODULE_LICENSE("GPL");