drm/udl: initial UDL driver (v4)

This is an initial drm/kms driver for the displaylink devices.

Supports fb_defio,
supports KMS dumb interface
supports 24bpp via conversion to 16bpp, hw can do this better.
supports hot unplug using new drm core features.

On an unplug, it disables connector polling, unplugs connectors
from sysfs, unplugs fbdev layer (using Kay's API), drops all the
USB device URBs, and call the drm core to unplug the device.

This driver is based in large parts on udlfb.c so I've licensed
it under GPLv2.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 227 insertions, 0 deletions

diff --git a/drivers/gpu/drm/udl/udl_gem.c b/drivers/gpu/drm/udl/udl_gem.c
new file mode 100644
index 000000000000..852642dc1187
--- /dev/null
+++ b/drivers/gpu/drm/udl/udl_gem.c
@@ -0,0 +1,227 @@
+/*
+ * Copyright (C) 2012 Red Hat
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License v2. See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+#include "drmP.h"
+#include "udl_drv.h"
+#include <linux/shmem_fs.h>
+
+struct udl_gem_object *udl_gem_alloc_object(struct drm_device *dev,
+                                            size_t size)
+{
+        struct udl_gem_object *obj;
+
+        obj = kzalloc(sizeof(*obj), GFP_KERNEL);
+        if (obj == NULL)
+                return NULL;
+
+        if (drm_gem_object_init(dev, &obj->base, size) != 0) {
+                kfree(obj);
+                return NULL;
+        }
+
+        return obj;
+}
+
+static int
+udl_gem_create(struct drm_file *file,
+               struct drm_device *dev,
+               uint64_t size,
+               uint32_t *handle_p)
+{
+        struct udl_gem_object *obj;
+        int ret;
+        u32 handle;
+
+        size = roundup(size, PAGE_SIZE);
+
+        obj = udl_gem_alloc_object(dev, size);
+        if (obj == NULL)
+                return -ENOMEM;
+
+        ret = drm_gem_handle_create(file, &obj->base, &handle);
+        if (ret) {
+                drm_gem_object_release(&obj->base);
+                kfree(obj);
+                return ret;
+        }
+
+        drm_gem_object_unreference(&obj->base);
+        *handle_p = handle;
+        return 0;
+}
+
+int udl_dumb_create(struct drm_file *file,
+                    struct drm_device *dev,
+                    struct drm_mode_create_dumb *args)
+{
+        args->pitch = args->width * ((args->bpp + 1) / 8);
+        args->size = args->pitch * args->height;
+        return udl_gem_create(file, dev,
+                              args->size, &args->handle);
+}
+
+int udl_dumb_destroy(struct drm_file *file, struct drm_device *dev,
+                     uint32_t handle)
+{
+        return drm_gem_handle_delete(file, handle);
+}
+
+int udl_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+        struct udl_gem_object *obj = to_udl_bo(vma->vm_private_data);
+        struct page *page;
+        unsigned int page_offset;
+        int ret = 0;
+
+        page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
+                PAGE_SHIFT;
+
+        if (!obj->pages)
+                return VM_FAULT_SIGBUS;
+
+        page = obj->pages[page_offset];
+        ret = vm_insert_page(vma, (unsigned long)vmf->virtual_address, page);
+        switch (ret) {
+        case -EAGAIN:
+                set_need_resched();
+        case 0:
+        case -ERESTARTSYS:
+                return VM_FAULT_NOPAGE;
+        case -ENOMEM:
+                return VM_FAULT_OOM;
+        default:
+                return VM_FAULT_SIGBUS;
+        }
+}
+
+int udl_gem_init_object(struct drm_gem_object *obj)
+{
+        BUG();
+
+        return 0;
+}
+
+static int udl_gem_get_pages(struct udl_gem_object *obj, gfp_t gfpmask)
+{
+        int page_count, i;
+        struct page *page;
+        struct inode *inode;
+        struct address_space *mapping;
+
+        if (obj->pages)
+                return 0;
+
+        page_count = obj->base.size / PAGE_SIZE;
+        BUG_ON(obj->pages != NULL);
+        obj->pages = drm_malloc_ab(page_count, sizeof(struct page *));
+        if (obj->pages == NULL)
+                return -ENOMEM;
+
+        inode = obj->base.filp->f_path.dentry->d_inode;
+        mapping = inode->i_mapping;
+        gfpmask |= mapping_gfp_mask(mapping);
+
+        for (i = 0; i < page_count; i++) {
+                page = shmem_read_mapping_page_gfp(mapping, i, gfpmask);
+                if (IS_ERR(page))
+                        goto err_pages;
+                obj->pages[i] = page;
+        }
+
+        return 0;
+err_pages:
+        while (i--)
+                page_cache_release(obj->pages[i]);
+        drm_free_large(obj->pages);
+        obj->pages = NULL;
+        return PTR_ERR(page);
+}
+
+static void udl_gem_put_pages(struct udl_gem_object *obj)
+{
+        int page_count = obj->base.size / PAGE_SIZE;
+        int i;
+
+        for (i = 0; i < page_count; i++)
+                page_cache_release(obj->pages[i]);
+
+        drm_free_large(obj->pages);
+        obj->pages = NULL;
+}
+
+int udl_gem_vmap(struct udl_gem_object *obj)
+{
+        int page_count = obj->base.size / PAGE_SIZE;
+        int ret;
+
+        ret = udl_gem_get_pages(obj, GFP_KERNEL);
+        if (ret)
+                return ret;
+
+        obj->vmapping = vmap(obj->pages, page_count, 0, PAGE_KERNEL);
+        if (!obj->vmapping)
+                return -ENOMEM;
+        return 0;
+}
+
+void udl_gem_vunmap(struct udl_gem_object *obj)
+{
+        if (obj->vmapping)
+                vunmap(obj->vmapping);
+
+        udl_gem_put_pages(obj);
+}
+
+void udl_gem_free_object(struct drm_gem_object *gem_obj)
+{
+        struct udl_gem_object *obj = to_udl_bo(gem_obj);
+
+        if (obj->vmapping)
+                udl_gem_vunmap(obj);
+
+        if (obj->pages)
+                udl_gem_put_pages(obj);
+
+        if (gem_obj->map_list.map)
+                drm_gem_free_mmap_offset(gem_obj);
+}
+
+/* the dumb interface doesn't work with the GEM straight MMAP
+   interface, it expects to do MMAP on the drm fd, like normal */
+int udl_gem_mmap(struct drm_file *file, struct drm_device *dev,
+                 uint32_t handle, uint64_t *offset)
+{
+        struct udl_gem_object *gobj;
+        struct drm_gem_object *obj;
+        int ret = 0;
+
+        mutex_lock(&dev->struct_mutex);
+        obj = drm_gem_object_lookup(dev, file, handle);
+        if (obj == NULL) {
+                ret = -ENOENT;
+                goto unlock;
+        }
+        gobj = to_udl_bo(obj);
+
+        ret = udl_gem_get_pages(gobj, GFP_KERNEL);
+        if (ret)
+                return ret;
+        if (!gobj->base.map_list.map) {
+                ret = drm_gem_create_mmap_offset(obj);
+                if (ret)
+                        goto out;
+        }
+
+        *offset = (u64)gobj->base.map_list.hash.key << PAGE_SHIFT;
+
+out:
+        drm_gem_object_unreference(&gobj->base);
+unlock:
+        mutex_unlock(&dev->struct_mutex);
+        return ret;
+}