root/include/video/udlfb.h

#ifndef UDLFB_H
#define UDLFB_H

/*
 * TODO: Propose standard fb.h ioctl for reporting damage,
 * using _IOWR() and one of the existing area structs from fb.h
 * Consider these ioctls deprecated, but they're still used by the
 * DisplayLink X server as yet - need both to be modified in tandem
 * when new ioctl(s) are ready.
 */
#define DLFB_IOCTL_RETURN_EDID   0xAD
#define DLFB_IOCTL_REPORT_DAMAGE 0xAA
struct dloarea {
        int x, y;
        int w, h;
        int x2, y2;
};

struct urb_node {
        struct list_head entry;
        struct dlfb_data *dev;
        struct delayed_work release_urb_work;
        struct urb *urb;
};

struct urb_list {
        struct list_head list;
        spinlock_t lock;
        struct semaphore limit_sem;
        int available;
        int count;
        size_t size;
};

struct dlfb_data {
        struct usb_device *udev;
        struct device *gdev; /* &udev->dev */
        struct fb_info *info;
        struct urb_list urbs;
        struct kref kref;
        char *backing_buffer;
        int fb_count;
        bool virtualized; /* true when physical usb device not present */
        struct delayed_work init_framebuffer_work;
        struct delayed_work free_framebuffer_work;
        atomic_t usb_active; /* 0 = update virtual buffer, but no usb traffic */
        atomic_t lost_pixels; /* 1 = a render op failed. Need screen refresh */
        char *edid; /* null until we read edid from hw or get from sysfs */
        size_t edid_size;
        int sku_pixel_limit;
        int base16;
        int base8;
        u32 pseudo_palette[256];
        int blank_mode; /*one of FB_BLANK_ */
        /* blit-only rendering path metrics, exposed through sysfs */
        atomic_t bytes_rendered; /* raw pixel-bytes driver asked to render */
        atomic_t bytes_identical; /* saved effort with backbuffer comparison */
        atomic_t bytes_sent; /* to usb, after compression including overhead */
        atomic_t cpu_kcycles_used; /* transpired during pixel processing */
};

#define NR_USB_REQUEST_I2C_SUB_IO 0x02
#define NR_USB_REQUEST_CHANNEL 0x12

/* -BULK_SIZE as per usb-skeleton. Can we get full page and avoid overhead? */
#define BULK_SIZE 512
#define MAX_TRANSFER (PAGE_SIZE*16 - BULK_SIZE)
#define WRITES_IN_FLIGHT (4)

#define MAX_VENDOR_DESCRIPTOR_SIZE 256

#define GET_URB_TIMEOUT HZ
#define FREE_URB_TIMEOUT (HZ*2)

#define BPP                     2
#define MAX_CMD_PIXELS          255

#define RLX_HEADER_BYTES        7
#define MIN_RLX_PIX_BYTES       4
#define MIN_RLX_CMD_BYTES       (RLX_HEADER_BYTES + MIN_RLX_PIX_BYTES)

#define RLE_HEADER_BYTES        6
#define MIN_RLE_PIX_BYTES       3
#define MIN_RLE_CMD_BYTES       (RLE_HEADER_BYTES + MIN_RLE_PIX_BYTES)

#define RAW_HEADER_BYTES        6
#define MIN_RAW_PIX_BYTES       2
#define MIN_RAW_CMD_BYTES       (RAW_HEADER_BYTES + MIN_RAW_PIX_BYTES)

#define DL_DEFIO_WRITE_DELAY    5 /* fb_deferred_io.delay in jiffies */
#define DL_DEFIO_WRITE_DISABLE  (HZ*60) /* "disable" with long delay */

/* remove these once align.h patch is taken into kernel */
#define DL_ALIGN_UP(x, a) ALIGN(x, a)
#define DL_ALIGN_DOWN(x, a) ALIGN(x-(a-1), a)

#endif