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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * udlfb.c -- Framebuffer driver for DisplayLink USB controller4 *5 * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>6 * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>7 * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>8 *9 * Layout is based on skeletonfb by James Simmons and Geert Uytterhoeven,10 * usb-skeleton by GregKH.11 *12 * Device-specific portions based on information from Displaylink, with work13 * from Florian Echtler, Henrik Bjerregaard Pedersen, and others.14 */15 16#include <linux/module.h>17#include <linux/kernel.h>18#include <linux/init.h>19#include <linux/usb.h>20#include <linux/uaccess.h>21#include <linux/mm.h>22#include <linux/fb.h>23#include <linux/vmalloc.h>24#include <linux/slab.h>25#include <linux/delay.h>26#include <linux/unaligned.h>27#include <video/udlfb.h>28#include "edid.h"29 30#define OUT_EP_NUM	1	/* The endpoint number we will use */31 32static const struct fb_fix_screeninfo dlfb_fix = {33	.id =           "udlfb",34	.type =         FB_TYPE_PACKED_PIXELS,35	.visual =       FB_VISUAL_TRUECOLOR,36	.xpanstep =     0,37	.ypanstep =     0,38	.ywrapstep =    0,39	.accel =        FB_ACCEL_NONE,40};41 42static const u32 udlfb_info_flags = FBINFO_READS_FAST |43		FBINFO_VIRTFB |44		FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT |45		FBINFO_HWACCEL_COPYAREA | FBINFO_MISC_ALWAYS_SETPAR;46 47/*48 * There are many DisplayLink-based graphics products, all with unique PIDs.49 * So we match on DisplayLink's VID + Vendor-Defined Interface Class (0xff)50 * We also require a match on SubClass (0x00) and Protocol (0x00),51 * which is compatible with all known USB 2.0 era graphics chips and firmware,52 * but allows DisplayLink to increment those for any future incompatible chips53 */54static const struct usb_device_id id_table[] = {55	{.idVendor = 0x17e9,56	 .bInterfaceClass = 0xff,57	 .bInterfaceSubClass = 0x00,58	 .bInterfaceProtocol = 0x00,59	 .match_flags = USB_DEVICE_ID_MATCH_VENDOR |60		USB_DEVICE_ID_MATCH_INT_CLASS |61		USB_DEVICE_ID_MATCH_INT_SUBCLASS |62		USB_DEVICE_ID_MATCH_INT_PROTOCOL,63	},64	{},65};66MODULE_DEVICE_TABLE(usb, id_table);67 68/* module options */69static bool console = true; /* Allow fbcon to open framebuffer */70static bool fb_defio = true;  /* Detect mmap writes using page faults */71static bool shadow = true; /* Optionally disable shadow framebuffer */72static int pixel_limit; /* Optionally force a pixel resolution limit */73 74struct dlfb_deferred_free {75	struct list_head list;76	void *mem;77};78 79static int dlfb_realloc_framebuffer(struct dlfb_data *dlfb, struct fb_info *info, u32 new_len);80 81/* dlfb keeps a list of urbs for efficient bulk transfers */82static void dlfb_urb_completion(struct urb *urb);83static struct urb *dlfb_get_urb(struct dlfb_data *dlfb);84static int dlfb_submit_urb(struct dlfb_data *dlfb, struct urb * urb, size_t len);85static int dlfb_alloc_urb_list(struct dlfb_data *dlfb, int count, size_t size);86static void dlfb_free_urb_list(struct dlfb_data *dlfb);87 88/*89 * All DisplayLink bulk operations start with 0xAF, followed by specific code90 * All operations are written to buffers which then later get sent to device91 */92static char *dlfb_set_register(char *buf, u8 reg, u8 val)93{94	*buf++ = 0xAF;95	*buf++ = 0x20;96	*buf++ = reg;97	*buf++ = val;98	return buf;99}100 101static char *dlfb_vidreg_lock(char *buf)102{103	return dlfb_set_register(buf, 0xFF, 0x00);104}105 106static char *dlfb_vidreg_unlock(char *buf)107{108	return dlfb_set_register(buf, 0xFF, 0xFF);109}110 111/*112 * Map FB_BLANK_* to DisplayLink register113 * DLReg FB_BLANK_*114 * ----- -----------------------------115 *  0x00 FB_BLANK_UNBLANK (0)116 *  0x01 FB_BLANK (1)117 *  0x03 FB_BLANK_VSYNC_SUSPEND (2)118 *  0x05 FB_BLANK_HSYNC_SUSPEND (3)119 *  0x07 FB_BLANK_POWERDOWN (4) Note: requires modeset to come back120 */121static char *dlfb_blanking(char *buf, int fb_blank)122{123	u8 reg;124 125	switch (fb_blank) {126	case FB_BLANK_POWERDOWN:127		reg = 0x07;128		break;129	case FB_BLANK_HSYNC_SUSPEND:130		reg = 0x05;131		break;132	case FB_BLANK_VSYNC_SUSPEND:133		reg = 0x03;134		break;135	case FB_BLANK_NORMAL:136		reg = 0x01;137		break;138	default:139		reg = 0x00;140	}141 142	buf = dlfb_set_register(buf, 0x1F, reg);143 144	return buf;145}146 147static char *dlfb_set_color_depth(char *buf, u8 selection)148{149	return dlfb_set_register(buf, 0x00, selection);150}151 152static char *dlfb_set_base16bpp(char *wrptr, u32 base)153{154	/* the base pointer is 16 bits wide, 0x20 is hi byte. */155	wrptr = dlfb_set_register(wrptr, 0x20, base >> 16);156	wrptr = dlfb_set_register(wrptr, 0x21, base >> 8);157	return dlfb_set_register(wrptr, 0x22, base);158}159 160/*161 * DisplayLink HW has separate 16bpp and 8bpp framebuffers.162 * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer163 */164static char *dlfb_set_base8bpp(char *wrptr, u32 base)165{166	wrptr = dlfb_set_register(wrptr, 0x26, base >> 16);167	wrptr = dlfb_set_register(wrptr, 0x27, base >> 8);168	return dlfb_set_register(wrptr, 0x28, base);169}170 171static char *dlfb_set_register_16(char *wrptr, u8 reg, u16 value)172{173	wrptr = dlfb_set_register(wrptr, reg, value >> 8);174	return dlfb_set_register(wrptr, reg+1, value);175}176 177/*178 * This is kind of weird because the controller takes some179 * register values in a different byte order than other registers.180 */181static char *dlfb_set_register_16be(char *wrptr, u8 reg, u16 value)182{183	wrptr = dlfb_set_register(wrptr, reg, value);184	return dlfb_set_register(wrptr, reg+1, value >> 8);185}186 187/*188 * LFSR is linear feedback shift register. The reason we have this is189 * because the display controller needs to minimize the clock depth of190 * various counters used in the display path. So this code reverses the191 * provided value into the lfsr16 value by counting backwards to get192 * the value that needs to be set in the hardware comparator to get the193 * same actual count. This makes sense once you read above a couple of194 * times and think about it from a hardware perspective.195 */196static u16 dlfb_lfsr16(u16 actual_count)197{198	u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */199 200	while (actual_count--) {201		lv =	 ((lv << 1) |202			(((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1))203			& 0xFFFF;204	}205 206	return (u16) lv;207}208 209/*210 * This does LFSR conversion on the value that is to be written.211 * See LFSR explanation above for more detail.212 */213static char *dlfb_set_register_lfsr16(char *wrptr, u8 reg, u16 value)214{215	return dlfb_set_register_16(wrptr, reg, dlfb_lfsr16(value));216}217 218/*219 * This takes a standard fbdev screeninfo struct and all of its monitor mode220 * details and converts them into the DisplayLink equivalent register commands.221 */222static char *dlfb_set_vid_cmds(char *wrptr, struct fb_var_screeninfo *var)223{224	u16 xds, yds;225	u16 xde, yde;226	u16 yec;227 228	/* x display start */229	xds = var->left_margin + var->hsync_len;230	wrptr = dlfb_set_register_lfsr16(wrptr, 0x01, xds);231	/* x display end */232	xde = xds + var->xres;233	wrptr = dlfb_set_register_lfsr16(wrptr, 0x03, xde);234 235	/* y display start */236	yds = var->upper_margin + var->vsync_len;237	wrptr = dlfb_set_register_lfsr16(wrptr, 0x05, yds);238	/* y display end */239	yde = yds + var->yres;240	wrptr = dlfb_set_register_lfsr16(wrptr, 0x07, yde);241 242	/* x end count is active + blanking - 1 */243	wrptr = dlfb_set_register_lfsr16(wrptr, 0x09,244			xde + var->right_margin - 1);245 246	/* libdlo hardcodes hsync start to 1 */247	wrptr = dlfb_set_register_lfsr16(wrptr, 0x0B, 1);248 249	/* hsync end is width of sync pulse + 1 */250	wrptr = dlfb_set_register_lfsr16(wrptr, 0x0D, var->hsync_len + 1);251 252	/* hpixels is active pixels */253	wrptr = dlfb_set_register_16(wrptr, 0x0F, var->xres);254 255	/* yendcount is vertical active + vertical blanking */256	yec = var->yres + var->upper_margin + var->lower_margin +257			var->vsync_len;258	wrptr = dlfb_set_register_lfsr16(wrptr, 0x11, yec);259 260	/* libdlo hardcodes vsync start to 0 */261	wrptr = dlfb_set_register_lfsr16(wrptr, 0x13, 0);262 263	/* vsync end is width of vsync pulse */264	wrptr = dlfb_set_register_lfsr16(wrptr, 0x15, var->vsync_len);265 266	/* vpixels is active pixels */267	wrptr = dlfb_set_register_16(wrptr, 0x17, var->yres);268 269	/* convert picoseconds to 5kHz multiple for pclk5k = x * 1E12/5k */270	wrptr = dlfb_set_register_16be(wrptr, 0x1B,271			200*1000*1000/var->pixclock);272 273	return wrptr;274}275 276/*277 * This takes a standard fbdev screeninfo struct that was fetched or prepared278 * and then generates the appropriate command sequence that then drives the279 * display controller.280 */281static int dlfb_set_video_mode(struct dlfb_data *dlfb,282				struct fb_var_screeninfo *var)283{284	char *buf;285	char *wrptr;286	int retval;287	int writesize;288	struct urb *urb;289 290	if (!atomic_read(&dlfb->usb_active))291		return -EPERM;292 293	urb = dlfb_get_urb(dlfb);294	if (!urb)295		return -ENOMEM;296 297	buf = (char *) urb->transfer_buffer;298 299	/*300	* This first section has to do with setting the base address on the301	* controller * associated with the display. There are 2 base302	* pointers, currently, we only * use the 16 bpp segment.303	*/304	wrptr = dlfb_vidreg_lock(buf);305	wrptr = dlfb_set_color_depth(wrptr, 0x00);306	/* set base for 16bpp segment to 0 */307	wrptr = dlfb_set_base16bpp(wrptr, 0);308	/* set base for 8bpp segment to end of fb */309	wrptr = dlfb_set_base8bpp(wrptr, dlfb->info->fix.smem_len);310 311	wrptr = dlfb_set_vid_cmds(wrptr, var);312	wrptr = dlfb_blanking(wrptr, FB_BLANK_UNBLANK);313	wrptr = dlfb_vidreg_unlock(wrptr);314 315	writesize = wrptr - buf;316 317	retval = dlfb_submit_urb(dlfb, urb, writesize);318 319	dlfb->blank_mode = FB_BLANK_UNBLANK;320 321	return retval;322}323 324static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma)325{326	unsigned long start = vma->vm_start;327	unsigned long size = vma->vm_end - vma->vm_start;328	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;329	unsigned long page, pos;330 331	if (info->fbdefio)332		return fb_deferred_io_mmap(info, vma);333 334	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);335 336	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))337		return -EINVAL;338	if (size > info->fix.smem_len)339		return -EINVAL;340	if (offset > info->fix.smem_len - size)341		return -EINVAL;342 343	pos = (unsigned long)info->fix.smem_start + offset;344 345	dev_dbg(info->dev, "mmap() framebuffer addr:%lu size:%lu\n",346		pos, size);347 348	while (size > 0) {349		page = vmalloc_to_pfn((void *)pos);350		if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED))351			return -EAGAIN;352 353		start += PAGE_SIZE;354		pos += PAGE_SIZE;355		if (size > PAGE_SIZE)356			size -= PAGE_SIZE;357		else358			size = 0;359	}360 361	return 0;362}363 364/*365 * Trims identical data from front and back of line366 * Sets new front buffer address and width367 * And returns byte count of identical pixels368 * Assumes CPU natural alignment (unsigned long)369 * for back and front buffer ptrs and width370 */371static int dlfb_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes)372{373	int j, k;374	const unsigned long *back = (const unsigned long *) bback;375	const unsigned long *front = (const unsigned long *) *bfront;376	const int width = *width_bytes / sizeof(unsigned long);377	int identical;378	int start = width;379	int end = width;380 381	for (j = 0; j < width; j++) {382		if (back[j] != front[j]) {383			start = j;384			break;385		}386	}387 388	for (k = width - 1; k > j; k--) {389		if (back[k] != front[k]) {390			end = k+1;391			break;392		}393	}394 395	identical = start + (width - end);396	*bfront = (u8 *) &front[start];397	*width_bytes = (end - start) * sizeof(unsigned long);398 399	return identical * sizeof(unsigned long);400}401 402/*403 * Render a command stream for an encoded horizontal line segment of pixels.404 *405 * A command buffer holds several commands.406 * It always begins with a fresh command header407 * (the protocol doesn't require this, but we enforce it to allow408 * multiple buffers to be potentially encoded and sent in parallel).409 * A single command encodes one contiguous horizontal line of pixels410 *411 * The function relies on the client to do all allocation, so that412 * rendering can be done directly to output buffers (e.g. USB URBs).413 * The function fills the supplied command buffer, providing information414 * on where it left off, so the client may call in again with additional415 * buffers if the line will take several buffers to complete.416 *417 * A single command can transmit a maximum of 256 pixels,418 * regardless of the compression ratio (protocol design limit).419 * To the hardware, 0 for a size byte means 256420 *421 * Rather than 256 pixel commands which are either rl or raw encoded,422 * the rlx command simply assumes alternating raw and rl spans within one cmd.423 * This has a slightly larger header overhead, but produces more even results.424 * It also processes all data (read and write) in a single pass.425 * Performance benchmarks of common cases show it having just slightly better426 * compression than 256 pixel raw or rle commands, with similar CPU consumpion.427 * But for very rl friendly data, will compress not quite as well.428 */429static void dlfb_compress_hline(430	const uint16_t **pixel_start_ptr,431	const uint16_t *const pixel_end,432	uint32_t *device_address_ptr,433	uint8_t **command_buffer_ptr,434	const uint8_t *const cmd_buffer_end,435	unsigned long back_buffer_offset,436	int *ident_ptr)437{438	const uint16_t *pixel = *pixel_start_ptr;439	uint32_t dev_addr  = *device_address_ptr;440	uint8_t *cmd = *command_buffer_ptr;441 442	while ((pixel_end > pixel) &&443	       (cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) {444		uint8_t *raw_pixels_count_byte = NULL;445		uint8_t *cmd_pixels_count_byte = NULL;446		const uint16_t *raw_pixel_start = NULL;447		const uint16_t *cmd_pixel_start, *cmd_pixel_end = NULL;448 449		if (back_buffer_offset &&450		    *pixel == *(u16 *)((u8 *)pixel + back_buffer_offset)) {451			pixel++;452			dev_addr += BPP;453			(*ident_ptr)++;454			continue;455		}456 457		*cmd++ = 0xAF;458		*cmd++ = 0x6B;459		*cmd++ = dev_addr >> 16;460		*cmd++ = dev_addr >> 8;461		*cmd++ = dev_addr;462 463		cmd_pixels_count_byte = cmd++; /*  we'll know this later */464		cmd_pixel_start = pixel;465 466		raw_pixels_count_byte = cmd++; /*  we'll know this later */467		raw_pixel_start = pixel;468 469		cmd_pixel_end = pixel + min3(MAX_CMD_PIXELS + 1UL,470					(unsigned long)(pixel_end - pixel),471					(unsigned long)(cmd_buffer_end - 1 - cmd) / BPP);472 473		if (back_buffer_offset) {474			/* note: the framebuffer may change under us, so we must test for underflow */475			while (cmd_pixel_end - 1 > pixel &&476			       *(cmd_pixel_end - 1) == *(u16 *)((u8 *)(cmd_pixel_end - 1) + back_buffer_offset))477				cmd_pixel_end--;478		}479 480		while (pixel < cmd_pixel_end) {481			const uint16_t * const repeating_pixel = pixel;482			u16 pixel_value = *pixel;483 484			put_unaligned_be16(pixel_value, cmd);485			if (back_buffer_offset)486				*(u16 *)((u8 *)pixel + back_buffer_offset) = pixel_value;487			cmd += 2;488			pixel++;489 490			if (unlikely((pixel < cmd_pixel_end) &&491				     (*pixel == pixel_value))) {492				/* go back and fill in raw pixel count */493				*raw_pixels_count_byte = ((repeating_pixel -494						raw_pixel_start) + 1) & 0xFF;495 496				do {497					if (back_buffer_offset)498						*(u16 *)((u8 *)pixel + back_buffer_offset) = pixel_value;499					pixel++;500				} while ((pixel < cmd_pixel_end) &&501					 (*pixel == pixel_value));502 503				/* immediately after raw data is repeat byte */504				*cmd++ = ((pixel - repeating_pixel) - 1) & 0xFF;505 506				/* Then start another raw pixel span */507				raw_pixel_start = pixel;508				raw_pixels_count_byte = cmd++;509			}510		}511 512		if (pixel > raw_pixel_start) {513			/* finalize last RAW span */514			*raw_pixels_count_byte = (pixel-raw_pixel_start) & 0xFF;515		} else {516			/* undo unused byte */517			cmd--;518		}519 520		*cmd_pixels_count_byte = (pixel - cmd_pixel_start) & 0xFF;521		dev_addr += (u8 *)pixel - (u8 *)cmd_pixel_start;522	}523 524	if (cmd_buffer_end - MIN_RLX_CMD_BYTES <= cmd) {525		/* Fill leftover bytes with no-ops */526		if (cmd_buffer_end > cmd)527			memset(cmd, 0xAF, cmd_buffer_end - cmd);528		cmd = (uint8_t *) cmd_buffer_end;529	}530 531	*command_buffer_ptr = cmd;532	*pixel_start_ptr = pixel;533	*device_address_ptr = dev_addr;534}535 536/*537 * There are 3 copies of every pixel: The front buffer that the fbdev538 * client renders to, the actual framebuffer across the USB bus in hardware539 * (that we can only write to, slowly, and can never read), and (optionally)540 * our shadow copy that tracks what's been sent to that hardware buffer.541 */542static int dlfb_render_hline(struct dlfb_data *dlfb, struct urb **urb_ptr,543			      const char *front, char **urb_buf_ptr,544			      u32 byte_offset, u32 byte_width,545			      int *ident_ptr, int *sent_ptr)546{547	const u8 *line_start, *line_end, *next_pixel;548	u32 dev_addr = dlfb->base16 + byte_offset;549	struct urb *urb = *urb_ptr;550	u8 *cmd = *urb_buf_ptr;551	u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length;552	unsigned long back_buffer_offset = 0;553 554	line_start = (u8 *) (front + byte_offset);555	next_pixel = line_start;556	line_end = next_pixel + byte_width;557 558	if (dlfb->backing_buffer) {559		int offset;560		const u8 *back_start = (u8 *) (dlfb->backing_buffer561						+ byte_offset);562 563		back_buffer_offset = (unsigned long)back_start - (unsigned long)line_start;564 565		*ident_ptr += dlfb_trim_hline(back_start, &next_pixel,566			&byte_width);567 568		offset = next_pixel - line_start;569		line_end = next_pixel + byte_width;570		dev_addr += offset;571		back_start += offset;572		line_start += offset;573	}574 575	while (next_pixel < line_end) {576 577		dlfb_compress_hline((const uint16_t **) &next_pixel,578			     (const uint16_t *) line_end, &dev_addr,579			(u8 **) &cmd, (u8 *) cmd_end, back_buffer_offset,580			ident_ptr);581 582		if (cmd >= cmd_end) {583			int len = cmd - (u8 *) urb->transfer_buffer;584			if (dlfb_submit_urb(dlfb, urb, len))585				return 1; /* lost pixels is set */586			*sent_ptr += len;587			urb = dlfb_get_urb(dlfb);588			if (!urb)589				return 1; /* lost_pixels is set */590			*urb_ptr = urb;591			cmd = urb->transfer_buffer;592			cmd_end = &cmd[urb->transfer_buffer_length];593		}594	}595 596	*urb_buf_ptr = cmd;597 598	return 0;599}600 601static int dlfb_handle_damage(struct dlfb_data *dlfb, int x, int y, int width, int height)602{603	int i, ret;604	char *cmd;605	cycles_t start_cycles, end_cycles;606	int bytes_sent = 0;607	int bytes_identical = 0;608	struct urb *urb;609	int aligned_x;610 611	start_cycles = get_cycles();612 613	mutex_lock(&dlfb->render_mutex);614 615	aligned_x = DL_ALIGN_DOWN(x, sizeof(unsigned long));616	width = DL_ALIGN_UP(width + (x-aligned_x), sizeof(unsigned long));617	x = aligned_x;618 619	if ((width <= 0) ||620	    (x + width > dlfb->info->var.xres) ||621	    (y + height > dlfb->info->var.yres)) {622		ret = -EINVAL;623		goto unlock_ret;624	}625 626	if (!atomic_read(&dlfb->usb_active)) {627		ret = 0;628		goto unlock_ret;629	}630 631	urb = dlfb_get_urb(dlfb);632	if (!urb) {633		ret = 0;634		goto unlock_ret;635	}636	cmd = urb->transfer_buffer;637 638	for (i = y; i < y + height ; i++) {639		const int line_offset = dlfb->info->fix.line_length * i;640		const int byte_offset = line_offset + (x * BPP);641 642		if (dlfb_render_hline(dlfb, &urb,643				      (char *) dlfb->info->fix.smem_start,644				      &cmd, byte_offset, width * BPP,645				      &bytes_identical, &bytes_sent))646			goto error;647	}648 649	if (cmd > (char *) urb->transfer_buffer) {650		int len;651		if (cmd < (char *) urb->transfer_buffer + urb->transfer_buffer_length)652			*cmd++ = 0xAF;653		/* Send partial buffer remaining before exiting */654		len = cmd - (char *) urb->transfer_buffer;655		dlfb_submit_urb(dlfb, urb, len);656		bytes_sent += len;657	} else658		dlfb_urb_completion(urb);659 660error:661	atomic_add(bytes_sent, &dlfb->bytes_sent);662	atomic_add(bytes_identical, &dlfb->bytes_identical);663	atomic_add(width*height*2, &dlfb->bytes_rendered);664	end_cycles = get_cycles();665	atomic_add(((unsigned int) ((end_cycles - start_cycles)666		    >> 10)), /* Kcycles */667		   &dlfb->cpu_kcycles_used);668 669	ret = 0;670 671unlock_ret:672	mutex_unlock(&dlfb->render_mutex);673	return ret;674}675 676static void dlfb_init_damage(struct dlfb_data *dlfb)677{678	dlfb->damage_x = INT_MAX;679	dlfb->damage_x2 = 0;680	dlfb->damage_y = INT_MAX;681	dlfb->damage_y2 = 0;682}683 684static void dlfb_damage_work(struct work_struct *w)685{686	struct dlfb_data *dlfb = container_of(w, struct dlfb_data, damage_work);687	int x, x2, y, y2;688 689	spin_lock_irq(&dlfb->damage_lock);690	x = dlfb->damage_x;691	x2 = dlfb->damage_x2;692	y = dlfb->damage_y;693	y2 = dlfb->damage_y2;694	dlfb_init_damage(dlfb);695	spin_unlock_irq(&dlfb->damage_lock);696 697	if (x < x2 && y < y2)698		dlfb_handle_damage(dlfb, x, y, x2 - x, y2 - y);699}700 701static void dlfb_offload_damage(struct dlfb_data *dlfb, int x, int y, int width, int height)702{703	unsigned long flags;704	int x2 = x + width;705	int y2 = y + height;706 707	if (x >= x2 || y >= y2)708		return;709 710	spin_lock_irqsave(&dlfb->damage_lock, flags);711	dlfb->damage_x = min(x, dlfb->damage_x);712	dlfb->damage_x2 = max(x2, dlfb->damage_x2);713	dlfb->damage_y = min(y, dlfb->damage_y);714	dlfb->damage_y2 = max(y2, dlfb->damage_y2);715	spin_unlock_irqrestore(&dlfb->damage_lock, flags);716 717	schedule_work(&dlfb->damage_work);718}719 720/*721 * NOTE: fb_defio.c is holding info->fbdefio.mutex722 *   Touching ANY framebuffer memory that triggers a page fault723 *   in fb_defio will cause a deadlock, when it also tries to724 *   grab the same mutex.725 */726static void dlfb_dpy_deferred_io(struct fb_info *info, struct list_head *pagereflist)727{728	struct fb_deferred_io_pageref *pageref;729	struct dlfb_data *dlfb = info->par;730	struct urb *urb;731	char *cmd;732	cycles_t start_cycles, end_cycles;733	int bytes_sent = 0;734	int bytes_identical = 0;735	int bytes_rendered = 0;736 737	mutex_lock(&dlfb->render_mutex);738 739	if (!fb_defio)740		goto unlock_ret;741 742	if (!atomic_read(&dlfb->usb_active))743		goto unlock_ret;744 745	start_cycles = get_cycles();746 747	urb = dlfb_get_urb(dlfb);748	if (!urb)749		goto unlock_ret;750 751	cmd = urb->transfer_buffer;752 753	/* walk the written page list and render each to device */754	list_for_each_entry(pageref, pagereflist, list) {755		if (dlfb_render_hline(dlfb, &urb, (char *) info->fix.smem_start,756				      &cmd, pageref->offset, PAGE_SIZE,757				      &bytes_identical, &bytes_sent))758			goto error;759		bytes_rendered += PAGE_SIZE;760	}761 762	if (cmd > (char *) urb->transfer_buffer) {763		int len;764		if (cmd < (char *) urb->transfer_buffer + urb->transfer_buffer_length)765			*cmd++ = 0xAF;766		/* Send partial buffer remaining before exiting */767		len = cmd - (char *) urb->transfer_buffer;768		dlfb_submit_urb(dlfb, urb, len);769		bytes_sent += len;770	} else771		dlfb_urb_completion(urb);772 773error:774	atomic_add(bytes_sent, &dlfb->bytes_sent);775	atomic_add(bytes_identical, &dlfb->bytes_identical);776	atomic_add(bytes_rendered, &dlfb->bytes_rendered);777	end_cycles = get_cycles();778	atomic_add(((unsigned int) ((end_cycles - start_cycles)779		    >> 10)), /* Kcycles */780		   &dlfb->cpu_kcycles_used);781unlock_ret:782	mutex_unlock(&dlfb->render_mutex);783}784 785static int dlfb_get_edid(struct dlfb_data *dlfb, char *edid, int len)786{787	int i, ret;788	char *rbuf;789 790	rbuf = kmalloc(2, GFP_KERNEL);791	if (!rbuf)792		return 0;793 794	for (i = 0; i < len; i++) {795		ret = usb_control_msg(dlfb->udev,796				      usb_rcvctrlpipe(dlfb->udev, 0), 0x02,797				      (0x80 | (0x02 << 5)), i << 8, 0xA1,798				      rbuf, 2, USB_CTRL_GET_TIMEOUT);799		if (ret < 2) {800			dev_err(&dlfb->udev->dev,801				"Read EDID byte %d failed: %d\n", i, ret);802			i--;803			break;804		}805		edid[i] = rbuf[1];806	}807 808	kfree(rbuf);809 810	return i;811}812 813static int dlfb_ops_ioctl(struct fb_info *info, unsigned int cmd,814				unsigned long arg)815{816 817	struct dlfb_data *dlfb = info->par;818 819	if (!atomic_read(&dlfb->usb_active))820		return 0;821 822	/* TODO: Update X server to get this from sysfs instead */823	if (cmd == DLFB_IOCTL_RETURN_EDID) {824		void __user *edid = (void __user *)arg;825		if (copy_to_user(edid, dlfb->edid, dlfb->edid_size))826			return -EFAULT;827		return 0;828	}829 830	/* TODO: Help propose a standard fb.h ioctl to report mmap damage */831	if (cmd == DLFB_IOCTL_REPORT_DAMAGE) {832		struct dloarea area;833 834		if (copy_from_user(&area, (void __user *)arg,835				  sizeof(struct dloarea)))836			return -EFAULT;837 838		/*839		 * If we have a damage-aware client, turn fb_defio "off"840		 * To avoid perf imact of unnecessary page fault handling.841		 * Done by resetting the delay for this fb_info to a very842		 * long period. Pages will become writable and stay that way.843		 * Reset to normal value when all clients have closed this fb.844		 */845		if (info->fbdefio)846			info->fbdefio->delay = DL_DEFIO_WRITE_DISABLE;847 848		if (area.x < 0)849			area.x = 0;850 851		if (area.x > info->var.xres)852			area.x = info->var.xres;853 854		if (area.y < 0)855			area.y = 0;856 857		if (area.y > info->var.yres)858			area.y = info->var.yres;859 860		dlfb_handle_damage(dlfb, area.x, area.y, area.w, area.h);861	}862 863	return 0;864}865 866/* taken from vesafb */867static int868dlfb_ops_setcolreg(unsigned regno, unsigned red, unsigned green,869	       unsigned blue, unsigned transp, struct fb_info *info)870{871	int err = 0;872 873	if (regno >= info->cmap.len)874		return 1;875 876	if (regno < 16) {877		if (info->var.red.offset == 10) {878			/* 1:5:5:5 */879			((u32 *) (info->pseudo_palette))[regno] =880			    ((red & 0xf800) >> 1) |881			    ((green & 0xf800) >> 6) | ((blue & 0xf800) >> 11);882		} else {883			/* 0:5:6:5 */884			((u32 *) (info->pseudo_palette))[regno] =885			    ((red & 0xf800)) |886			    ((green & 0xfc00) >> 5) | ((blue & 0xf800) >> 11);887		}888	}889 890	return err;891}892 893/*894 * It's common for several clients to have framebuffer open simultaneously.895 * e.g. both fbcon and X. Makes things interesting.896 * Assumes caller is holding info->lock (for open and release at least)897 */898static int dlfb_ops_open(struct fb_info *info, int user)899{900	struct dlfb_data *dlfb = info->par;901 902	/*903	 * fbcon aggressively connects to first framebuffer it finds,904	 * preventing other clients (X) from working properly. Usually905	 * not what the user wants. Fail by default with option to enable.906	 */907	if ((user == 0) && (!console))908		return -EBUSY;909 910	/* If the USB device is gone, we don't accept new opens */911	if (dlfb->virtualized)912		return -ENODEV;913 914	dlfb->fb_count++;915 916	if (fb_defio && (info->fbdefio == NULL)) {917		/* enable defio at last moment if not disabled by client */918 919		struct fb_deferred_io *fbdefio;920 921		fbdefio = kzalloc(sizeof(struct fb_deferred_io), GFP_KERNEL);922 923		if (fbdefio) {924			fbdefio->delay = DL_DEFIO_WRITE_DELAY;925			fbdefio->sort_pagereflist = true;926			fbdefio->deferred_io = dlfb_dpy_deferred_io;927		}928 929		info->fbdefio = fbdefio;930		fb_deferred_io_init(info);931	}932 933	dev_dbg(info->dev, "open, user=%d fb_info=%p count=%d\n",934		user, info, dlfb->fb_count);935 936	return 0;937}938 939static void dlfb_ops_destroy(struct fb_info *info)940{941	struct dlfb_data *dlfb = info->par;942 943	cancel_work_sync(&dlfb->damage_work);944 945	mutex_destroy(&dlfb->render_mutex);946 947	if (info->cmap.len != 0)948		fb_dealloc_cmap(&info->cmap);949	if (info->monspecs.modedb)950		fb_destroy_modedb(info->monspecs.modedb);951	vfree(info->screen_buffer);952 953	fb_destroy_modelist(&info->modelist);954 955	while (!list_empty(&dlfb->deferred_free)) {956		struct dlfb_deferred_free *d = list_entry(dlfb->deferred_free.next, struct dlfb_deferred_free, list);957		list_del(&d->list);958		vfree(d->mem);959		kfree(d);960	}961	vfree(dlfb->backing_buffer);962	kfree(dlfb->edid);963	dlfb_free_urb_list(dlfb);964	usb_put_dev(dlfb->udev);965	kfree(dlfb);966 967	/* Assume info structure is freed after this point */968	framebuffer_release(info);969}970 971/*972 * Assumes caller is holding info->lock mutex (for open and release at least)973 */974static int dlfb_ops_release(struct fb_info *info, int user)975{976	struct dlfb_data *dlfb = info->par;977 978	dlfb->fb_count--;979 980	if ((dlfb->fb_count == 0) && (info->fbdefio)) {981		fb_deferred_io_cleanup(info);982		kfree(info->fbdefio);983		info->fbdefio = NULL;984	}985 986	dev_dbg(info->dev, "release, user=%d count=%d\n", user, dlfb->fb_count);987 988	return 0;989}990 991/*992 * Check whether a video mode is supported by the DisplayLink chip993 * We start from monitor's modes, so don't need to filter that here994 */995static int dlfb_is_valid_mode(struct fb_videomode *mode, struct dlfb_data *dlfb)996{997	if (mode->xres * mode->yres > dlfb->sku_pixel_limit)998		return 0;999 1000	return 1;1001}1002 1003static void dlfb_var_color_format(struct fb_var_screeninfo *var)1004{1005	const struct fb_bitfield red = { 11, 5, 0 };1006	const struct fb_bitfield green = { 5, 6, 0 };1007	const struct fb_bitfield blue = { 0, 5, 0 };1008 1009	var->bits_per_pixel = 16;1010	var->red = red;1011	var->green = green;1012	var->blue = blue;1013}1014 1015static int dlfb_ops_check_var(struct fb_var_screeninfo *var,1016				struct fb_info *info)1017{1018	struct fb_videomode mode;1019	struct dlfb_data *dlfb = info->par;1020 1021	/* set device-specific elements of var unrelated to mode */1022	dlfb_var_color_format(var);1023 1024	fb_var_to_videomode(&mode, var);1025 1026	if (!dlfb_is_valid_mode(&mode, dlfb))1027		return -EINVAL;1028 1029	return 0;1030}1031 1032static int dlfb_ops_set_par(struct fb_info *info)1033{1034	struct dlfb_data *dlfb = info->par;1035	int result;1036	u16 *pix_framebuffer;1037	int i;1038	struct fb_var_screeninfo fvs;1039	u32 line_length = info->var.xres * (info->var.bits_per_pixel / 8);1040 1041	/* clear the activate field because it causes spurious miscompares */1042	fvs = info->var;1043	fvs.activate = 0;1044	fvs.vmode &= ~FB_VMODE_SMOOTH_XPAN;1045 1046	if (!memcmp(&dlfb->current_mode, &fvs, sizeof(struct fb_var_screeninfo)))1047		return 0;1048 1049	result = dlfb_realloc_framebuffer(dlfb, info, info->var.yres * line_length);1050	if (result)1051		return result;1052 1053	result = dlfb_set_video_mode(dlfb, &info->var);1054 1055	if (result)1056		return result;1057 1058	dlfb->current_mode = fvs;1059	info->fix.line_length = line_length;1060 1061	if (dlfb->fb_count == 0) {1062 1063		/* paint greenscreen */1064 1065		pix_framebuffer = (u16 *)info->screen_buffer;1066		for (i = 0; i < info->fix.smem_len / 2; i++)1067			pix_framebuffer[i] = 0x37e6;1068	}1069 1070	dlfb_handle_damage(dlfb, 0, 0, info->var.xres, info->var.yres);1071 1072	return 0;1073}1074 1075/* To fonzi the jukebox (e.g. make blanking changes take effect) */1076static char *dlfb_dummy_render(char *buf)1077{1078	*buf++ = 0xAF;1079	*buf++ = 0x6A; /* copy */1080	*buf++ = 0x00; /* from address*/1081	*buf++ = 0x00;1082	*buf++ = 0x00;1083	*buf++ = 0x01; /* one pixel */1084	*buf++ = 0x00; /* to address */1085	*buf++ = 0x00;1086	*buf++ = 0x00;1087	return buf;1088}1089 1090/*1091 * In order to come back from full DPMS off, we need to set the mode again1092 */1093static int dlfb_ops_blank(int blank_mode, struct fb_info *info)1094{1095	struct dlfb_data *dlfb = info->par;1096	char *bufptr;1097	struct urb *urb;1098 1099	dev_dbg(info->dev, "blank, mode %d --> %d\n",1100		dlfb->blank_mode, blank_mode);1101 1102	if ((dlfb->blank_mode == FB_BLANK_POWERDOWN) &&1103	    (blank_mode != FB_BLANK_POWERDOWN)) {1104 1105		/* returning from powerdown requires a fresh modeset */1106		dlfb_set_video_mode(dlfb, &info->var);1107	}1108 1109	urb = dlfb_get_urb(dlfb);1110	if (!urb)1111		return 0;1112 1113	bufptr = (char *) urb->transfer_buffer;1114	bufptr = dlfb_vidreg_lock(bufptr);1115	bufptr = dlfb_blanking(bufptr, blank_mode);1116	bufptr = dlfb_vidreg_unlock(bufptr);1117 1118	/* seems like a render op is needed to have blank change take effect */1119	bufptr = dlfb_dummy_render(bufptr);1120 1121	dlfb_submit_urb(dlfb, urb, bufptr -1122			(char *) urb->transfer_buffer);1123 1124	dlfb->blank_mode = blank_mode;1125 1126	return 0;1127}1128 1129static void dlfb_ops_damage_range(struct fb_info *info, off_t off, size_t len)1130{1131	struct dlfb_data *dlfb = info->par;1132	int start = max((int)(off / info->fix.line_length), 0);1133	int lines = min((u32)((len / info->fix.line_length) + 1), (u32)info->var.yres);1134 1135	dlfb_handle_damage(dlfb, 0, start, info->var.xres, lines);1136}1137 1138static void dlfb_ops_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height)1139{1140	struct dlfb_data *dlfb = info->par;1141 1142	dlfb_offload_damage(dlfb, x, y, width, height);1143}1144 1145FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(dlfb_ops,1146				   dlfb_ops_damage_range,1147				   dlfb_ops_damage_area)1148 1149static const struct fb_ops dlfb_ops = {1150	.owner = THIS_MODULE,1151	__FB_DEFAULT_DEFERRED_OPS_RDWR(dlfb_ops),1152	.fb_setcolreg = dlfb_ops_setcolreg,1153	__FB_DEFAULT_DEFERRED_OPS_DRAW(dlfb_ops),1154	.fb_mmap = dlfb_ops_mmap,1155	.fb_ioctl = dlfb_ops_ioctl,1156	.fb_open = dlfb_ops_open,1157	.fb_release = dlfb_ops_release,1158	.fb_blank = dlfb_ops_blank,1159	.fb_check_var = dlfb_ops_check_var,1160	.fb_set_par = dlfb_ops_set_par,1161	.fb_destroy = dlfb_ops_destroy,1162};1163 1164 1165static void dlfb_deferred_vfree(struct dlfb_data *dlfb, void *mem)1166{1167	struct dlfb_deferred_free *d = kmalloc(sizeof(struct dlfb_deferred_free), GFP_KERNEL);1168	if (!d)1169		return;1170	d->mem = mem;1171	list_add(&d->list, &dlfb->deferred_free);1172}1173 1174/*1175 * Assumes &info->lock held by caller1176 * Assumes no active clients have framebuffer open1177 */1178static int dlfb_realloc_framebuffer(struct dlfb_data *dlfb, struct fb_info *info, u32 new_len)1179{1180	u32 old_len = info->fix.smem_len;1181	const void *old_fb = info->screen_buffer;1182	unsigned char *new_fb;1183	unsigned char *new_back = NULL;1184 1185	new_len = PAGE_ALIGN(new_len);1186 1187	if (new_len > old_len) {1188		/*1189		 * Alloc system memory for virtual framebuffer1190		 */1191		new_fb = vmalloc(new_len);1192		if (!new_fb) {1193			dev_err(info->dev, "Virtual framebuffer alloc failed\n");1194			return -ENOMEM;1195		}1196		memset(new_fb, 0xff, new_len);1197 1198		if (info->screen_buffer) {1199			memcpy(new_fb, old_fb, old_len);1200			dlfb_deferred_vfree(dlfb, info->screen_buffer);1201		}1202 1203		info->screen_buffer = new_fb;1204		info->fix.smem_len = new_len;1205		info->fix.smem_start = (unsigned long) new_fb;1206		info->flags = udlfb_info_flags;1207 1208		/*1209		 * Second framebuffer copy to mirror the framebuffer state1210		 * on the physical USB device. We can function without this.1211		 * But with imperfect damage info we may send pixels over USB1212		 * that were, in fact, unchanged - wasting limited USB bandwidth1213		 */1214		if (shadow)1215			new_back = vzalloc(new_len);1216		if (!new_back)1217			dev_info(info->dev,1218				 "No shadow/backing buffer allocated\n");1219		else {1220			dlfb_deferred_vfree(dlfb, dlfb->backing_buffer);1221			dlfb->backing_buffer = new_back;1222		}1223	}1224	return 0;1225}1226 1227/*1228 * 1) Get EDID from hw, or use sw default1229 * 2) Parse into various fb_info structs1230 * 3) Allocate virtual framebuffer memory to back highest res mode1231 *1232 * Parses EDID into three places used by various parts of fbdev:1233 * fb_var_screeninfo contains the timing of the monitor's preferred mode1234 * fb_info.monspecs is full parsed EDID info, including monspecs.modedb1235 * fb_info.modelist is a linked list of all monitor & VESA modes which work1236 *1237 * If EDID is not readable/valid, then modelist is all VESA modes,1238 * monspecs is NULL, and fb_var_screeninfo is set to safe VESA mode1239 * Returns 0 if successful1240 */1241static int dlfb_setup_modes(struct dlfb_data *dlfb,1242			   struct fb_info *info,1243			   char *default_edid, size_t default_edid_size)1244{1245	char *edid;1246	int i, result = 0, tries = 3;1247	struct device *dev = info->device;1248	struct fb_videomode *mode;1249	const struct fb_videomode *default_vmode = NULL;1250 1251	if (info->dev) {1252		/* only use mutex if info has been registered */1253		mutex_lock(&info->lock);1254		/* parent device is used otherwise */1255		dev = info->dev;1256	}1257 1258	edid = kmalloc(EDID_LENGTH, GFP_KERNEL);1259	if (!edid) {1260		result = -ENOMEM;1261		goto error;1262	}1263 1264	fb_destroy_modelist(&info->modelist);1265	memset(&info->monspecs, 0, sizeof(info->monspecs));1266 1267	/*1268	 * Try to (re)read EDID from hardware first1269	 * EDID data may return, but not parse as valid1270	 * Try again a few times, in case of e.g. analog cable noise1271	 */1272	while (tries--) {1273 1274		i = dlfb_get_edid(dlfb, edid, EDID_LENGTH);1275 1276		if (i >= EDID_LENGTH)1277			fb_edid_to_monspecs(edid, &info->monspecs);1278 1279		if (info->monspecs.modedb_len > 0) {1280			dlfb->edid = edid;1281			dlfb->edid_size = i;1282			break;1283		}1284	}1285 1286	/* If that fails, use a previously returned EDID if available */1287	if (info->monspecs.modedb_len == 0) {1288		dev_err(dev, "Unable to get valid EDID from device/display\n");1289 1290		if (dlfb->edid) {1291			fb_edid_to_monspecs(dlfb->edid, &info->monspecs);1292			if (info->monspecs.modedb_len > 0)1293				dev_err(dev, "Using previously queried EDID\n");1294		}1295	}1296 1297	/* If that fails, use the default EDID we were handed */1298	if (info->monspecs.modedb_len == 0) {1299		if (default_edid_size >= EDID_LENGTH) {1300			fb_edid_to_monspecs(default_edid, &info->monspecs);1301			if (info->monspecs.modedb_len > 0) {1302				memcpy(edid, default_edid, default_edid_size);1303				dlfb->edid = edid;1304				dlfb->edid_size = default_edid_size;1305				dev_err(dev, "Using default/backup EDID\n");1306			}1307		}1308	}1309 1310	/* If we've got modes, let's pick a best default mode */1311	if (info->monspecs.modedb_len > 0) {1312 1313		for (i = 0; i < info->monspecs.modedb_len; i++) {1314			mode = &info->monspecs.modedb[i];1315			if (dlfb_is_valid_mode(mode, dlfb)) {1316				fb_add_videomode(mode, &info->modelist);1317			} else {1318				dev_dbg(dev, "Specified mode %dx%d too big\n",1319					mode->xres, mode->yres);1320				if (i == 0)1321					/* if we've removed top/best mode */1322					info->monspecs.misc1323						&= ~FB_MISC_1ST_DETAIL;1324			}1325		}1326 1327		default_vmode = fb_find_best_display(&info->monspecs,1328						     &info->modelist);1329	}1330 1331	/* If everything else has failed, fall back to safe default mode */1332	if (default_vmode == NULL) {1333 1334		struct fb_videomode fb_vmode = {0};1335 1336		/*1337		 * Add the standard VESA modes to our modelist1338		 * Since we don't have EDID, there may be modes that1339		 * overspec monitor and/or are incorrect aspect ratio, etc.1340		 * But at least the user has a chance to choose1341		 */1342		for (i = 0; i < VESA_MODEDB_SIZE; i++) {1343			mode = (struct fb_videomode *)&vesa_modes[i];1344			if (dlfb_is_valid_mode(mode, dlfb))1345				fb_add_videomode(mode, &info->modelist);1346			else1347				dev_dbg(dev, "VESA mode %dx%d too big\n",1348					mode->xres, mode->yres);1349		}1350 1351		/*1352		 * default to resolution safe for projectors1353		 * (since they are most common case without EDID)1354		 */1355		fb_vmode.xres = 800;1356		fb_vmode.yres = 600;1357		fb_vmode.refresh = 60;1358		default_vmode = fb_find_nearest_mode(&fb_vmode,1359						     &info->modelist);1360	}1361 1362	/* If we have good mode and no active clients*/1363	if ((default_vmode != NULL) && (dlfb->fb_count == 0)) {1364 1365		fb_videomode_to_var(&info->var, default_vmode);1366		dlfb_var_color_format(&info->var);1367 1368		/*1369		 * with mode size info, we can now alloc our framebuffer.1370		 */1371		memcpy(&info->fix, &dlfb_fix, sizeof(dlfb_fix));1372	} else1373		result = -EINVAL;1374 1375error:1376	if (edid && (dlfb->edid != edid))1377		kfree(edid);1378 1379	if (info->dev)1380		mutex_unlock(&info->lock);1381 1382	return result;1383}1384 1385static ssize_t metrics_bytes_rendered_show(struct device *fbdev,1386				   struct device_attribute *a, char *buf) {1387	struct fb_info *fb_info = dev_get_drvdata(fbdev);1388	struct dlfb_data *dlfb = fb_info->par;1389	return sysfs_emit(buf, "%u\n",1390			atomic_read(&dlfb->bytes_rendered));1391}1392 1393static ssize_t metrics_bytes_identical_show(struct device *fbdev,1394				   struct device_attribute *a, char *buf) {1395	struct fb_info *fb_info = dev_get_drvdata(fbdev);1396	struct dlfb_data *dlfb = fb_info->par;1397	return sysfs_emit(buf, "%u\n",1398			atomic_read(&dlfb->bytes_identical));1399}1400 1401static ssize_t metrics_bytes_sent_show(struct device *fbdev,1402				   struct device_attribute *a, char *buf) {1403	struct fb_info *fb_info = dev_get_drvdata(fbdev);1404	struct dlfb_data *dlfb = fb_info->par;1405	return sysfs_emit(buf, "%u\n",1406			atomic_read(&dlfb->bytes_sent));1407}1408 1409static ssize_t metrics_cpu_kcycles_used_show(struct device *fbdev,1410				   struct device_attribute *a, char *buf) {1411	struct fb_info *fb_info = dev_get_drvdata(fbdev);1412	struct dlfb_data *dlfb = fb_info->par;1413	return sysfs_emit(buf, "%u\n",1414			atomic_read(&dlfb->cpu_kcycles_used));1415}1416 1417static ssize_t edid_show(1418			struct file *filp,1419			struct kobject *kobj, struct bin_attribute *a,1420			 char *buf, loff_t off, size_t count) {1421	struct device *fbdev = kobj_to_dev(kobj);1422	struct fb_info *fb_info = dev_get_drvdata(fbdev);1423	struct dlfb_data *dlfb = fb_info->par;1424 1425	if (dlfb->edid == NULL)1426		return 0;1427 1428	if ((off >= dlfb->edid_size) || (count > dlfb->edid_size))1429		return 0;1430 1431	if (off + count > dlfb->edid_size)1432		count = dlfb->edid_size - off;1433 1434	memcpy(buf, dlfb->edid, count);1435 1436	return count;1437}1438 1439static ssize_t edid_store(1440			struct file *filp,1441			struct kobject *kobj, struct bin_attribute *a,1442			char *src, loff_t src_off, size_t src_size) {1443	struct device *fbdev = kobj_to_dev(kobj);1444	struct fb_info *fb_info = dev_get_drvdata(fbdev);1445	struct dlfb_data *dlfb = fb_info->par;1446	int ret;1447 1448	/* We only support write of entire EDID at once, no offset*/1449	if ((src_size != EDID_LENGTH) || (src_off != 0))1450		return -EINVAL;1451 1452	ret = dlfb_setup_modes(dlfb, fb_info, src, src_size);1453	if (ret)1454		return ret;1455 1456	if (!dlfb->edid || memcmp(src, dlfb->edid, src_size))1457		return -EINVAL;1458 1459	ret = dlfb_ops_set_par(fb_info);1460	if (ret)1461		return ret;1462 1463	return src_size;1464}1465 1466static ssize_t metrics_reset_store(struct device *fbdev,1467			   struct device_attribute *attr,1468			   const char *buf, size_t count)1469{1470	struct fb_info *fb_info = dev_get_drvdata(fbdev);1471	struct dlfb_data *dlfb = fb_info->par;1472 1473	atomic_set(&dlfb->bytes_rendered, 0);1474	atomic_set(&dlfb->bytes_identical, 0);1475	atomic_set(&dlfb->bytes_sent, 0);1476	atomic_set(&dlfb->cpu_kcycles_used, 0);1477 1478	return count;1479}1480 1481static const struct bin_attribute edid_attr = {1482	.attr.name = "edid",1483	.attr.mode = 0666,1484	.size = EDID_LENGTH,1485	.read = edid_show,1486	.write = edid_store1487};1488 1489static const struct device_attribute fb_device_attrs[] = {1490	__ATTR_RO(metrics_bytes_rendered),1491	__ATTR_RO(metrics_bytes_identical),1492	__ATTR_RO(metrics_bytes_sent),1493	__ATTR_RO(metrics_cpu_kcycles_used),1494	__ATTR(metrics_reset, S_IWUSR, NULL, metrics_reset_store),1495};1496 1497/*1498 * This is necessary before we can communicate with the display controller.1499 */1500static int dlfb_select_std_channel(struct dlfb_data *dlfb)1501{1502	int ret;1503	static const u8 set_def_chn[] = {1504				0x57, 0xCD, 0xDC, 0xA7,1505				0x1C, 0x88, 0x5E, 0x15,1506				0x60, 0xFE, 0xC6, 0x97,1507				0x16, 0x3D, 0x47, 0xF2  };1508 1509	ret = usb_control_msg_send(dlfb->udev, 0, NR_USB_REQUEST_CHANNEL,1510			(USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,1511			&set_def_chn, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT,1512			GFP_KERNEL);1513 1514	return ret;1515}1516 1517static int dlfb_parse_vendor_descriptor(struct dlfb_data *dlfb,1518					struct usb_interface *intf)1519{1520	char *desc;1521	char *buf;1522	char *desc_end;1523	int total_len;1524 1525	buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL);1526	if (!buf)1527		return false;1528	desc = buf;1529 1530	total_len = usb_get_descriptor(interface_to_usbdev(intf),1531					0x5f, /* vendor specific */1532					0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);1533 1534	/* if not found, look in configuration descriptor */1535	if (total_len < 0) {1536		if (0 == usb_get_extra_descriptor(intf->cur_altsetting,1537			0x5f, &desc))1538			total_len = (int) desc[0];1539	}1540 1541	if (total_len > 5) {1542		dev_info(&intf->dev,1543			 "vendor descriptor length: %d data: %11ph\n",1544			 total_len, desc);1545 1546		if ((desc[0] != total_len) || /* descriptor length */1547		    (desc[1] != 0x5f) ||   /* vendor descriptor type */1548		    (desc[2] != 0x01) ||   /* version (2 bytes) */1549		    (desc[3] != 0x00) ||1550		    (desc[4] != total_len - 2)) /* length after type */1551			goto unrecognized;1552 1553		desc_end = desc + total_len;1554		desc += 5; /* the fixed header we've already parsed */1555 1556		while (desc < desc_end) {1557			u8 length;1558			u16 key;1559 1560			key = *desc++;1561			key |= (u16)*desc++ << 8;1562			length = *desc++;1563 1564			switch (key) {1565			case 0x0200: { /* max_area */1566				u32 max_area = *desc++;1567				max_area |= (u32)*desc++ << 8;1568				max_area |= (u32)*desc++ << 16;1569				max_area |= (u32)*desc++ << 24;1570				dev_warn(&intf->dev,1571					 "DL chip limited to %d pixel modes\n",1572					 max_area);1573				dlfb->sku_pixel_limit = max_area;1574				break;1575			}1576			default:1577				break;1578			}1579			desc += length;1580		}1581	} else {1582		dev_info(&intf->dev, "vendor descriptor not available (%d)\n",1583			 total_len);1584	}1585 1586	goto success;1587 1588unrecognized:1589	/* allow udlfb to load for now even if firmware unrecognized */1590	dev_err(&intf->dev, "Unrecognized vendor firmware descriptor\n");1591 1592success:1593	kfree(buf);1594	return true;1595}1596 1597static int dlfb_usb_probe(struct usb_interface *intf,1598			  const struct usb_device_id *id)1599{1600	int i;1601	const struct device_attribute *attr;1602	struct dlfb_data *dlfb;1603	struct fb_info *info;1604	int retval;1605	struct usb_device *usbdev = interface_to_usbdev(intf);1606	static u8 out_ep[] = {OUT_EP_NUM + USB_DIR_OUT, 0};1607 1608	/* usb initialization */1609	dlfb = kzalloc(sizeof(*dlfb), GFP_KERNEL);1610	if (!dlfb) {1611		dev_err(&intf->dev, "%s: failed to allocate dlfb\n", __func__);1612		return -ENOMEM;1613	}1614 1615	INIT_LIST_HEAD(&dlfb->deferred_free);1616 1617	dlfb->udev = usb_get_dev(usbdev);1618	usb_set_intfdata(intf, dlfb);1619 1620	if (!usb_check_bulk_endpoints(intf, out_ep)) {1621		dev_err(&intf->dev, "Invalid DisplayLink device!\n");1622		retval = -EINVAL;1623		goto error;1624	}1625 1626	dev_dbg(&intf->dev, "console enable=%d\n", console);1627	dev_dbg(&intf->dev, "fb_defio enable=%d\n", fb_defio);1628	dev_dbg(&intf->dev, "shadow enable=%d\n", shadow);1629 1630	dlfb->sku_pixel_limit = 2048 * 1152; /* default to maximum */1631 1632	if (!dlfb_parse_vendor_descriptor(dlfb, intf)) {1633		dev_err(&intf->dev,1634			"firmware not recognized, incompatible device?\n");1635		retval = -ENODEV;1636		goto error;1637	}1638 1639	if (pixel_limit) {1640		dev_warn(&intf->dev,1641			 "DL chip limit of %d overridden to %d\n",1642			 dlfb->sku_pixel_limit, pixel_limit);1643		dlfb->sku_pixel_limit = pixel_limit;1644	}1645 1646 1647	/* allocates framebuffer driver structure, not framebuffer memory */1648	info = framebuffer_alloc(0, &dlfb->udev->dev);1649	if (!info) {1650		retval = -ENOMEM;1651		goto error;1652	}1653 1654	dlfb->info = info;1655	info->par = dlfb;1656	info->pseudo_palette = dlfb->pseudo_palette;1657	dlfb->ops = dlfb_ops;1658	info->fbops = &dlfb->ops;1659 1660	mutex_init(&dlfb->render_mutex);1661	dlfb_init_damage(dlfb);1662	spin_lock_init(&dlfb->damage_lock);1663	INIT_WORK(&dlfb->damage_work, dlfb_damage_work);1664 1665	INIT_LIST_HEAD(&info->modelist);1666 1667	if (!dlfb_alloc_urb_list(dlfb, WRITES_IN_FLIGHT, MAX_TRANSFER)) {1668		retval = -ENOMEM;1669		dev_err(&intf->dev, "unable to allocate urb list\n");1670		goto error;1671	}1672 1673	/* We don't register a new USB class. Our client interface is dlfbev */1674 1675	retval = fb_alloc_cmap(&info->cmap, 256, 0);1676	if (retval < 0) {1677		dev_err(info->device, "cmap allocation failed: %d\n", retval);1678		goto error;1679	}1680 1681	retval = dlfb_setup_modes(dlfb, info, NULL, 0);1682	if (retval != 0) {1683		dev_err(info->device,1684			"unable to find common mode for display and adapter\n");1685		goto error;1686	}1687 1688	/* ready to begin using device */1689 1690	atomic_set(&dlfb->usb_active, 1);1691	dlfb_select_std_channel(dlfb);1692 1693	dlfb_ops_check_var(&info->var, info);1694	retval = dlfb_ops_set_par(info);1695	if (retval)1696		goto error;1697 1698	retval = register_framebuffer(info);1699	if (retval < 0) {1700		dev_err(info->device, "unable to register framebuffer: %d\n",1701			retval);1702		goto error;1703	}1704 1705	for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) {1706		attr = &fb_device_attrs[i];1707		retval = device_create_file(info->dev, attr);1708		if (retval)1709			dev_warn(info->device,1710				 "failed to create '%s' attribute: %d\n",1711				 attr->attr.name, retval);1712	}1713 1714	retval = device_create_bin_file(info->dev, &edid_attr);1715	if (retval)1716		dev_warn(info->device, "failed to create '%s' attribute: %d\n",1717			 edid_attr.attr.name, retval);1718 1719	dev_info(info->device,1720		 "%s is DisplayLink USB device (%dx%d, %dK framebuffer memory)\n",1721		 dev_name(info->dev), info->var.xres, info->var.yres,1722		 ((dlfb->backing_buffer) ?1723		 info->fix.smem_len * 2 : info->fix.smem_len) >> 10);1724	return 0;1725 1726error:1727	if (dlfb->info) {1728		dlfb_ops_destroy(dlfb->info);1729	} else {1730		usb_put_dev(dlfb->udev);1731		kfree(dlfb);1732	}1733	return retval;1734}1735 1736static void dlfb_usb_disconnect(struct usb_interface *intf)1737{1738	struct dlfb_data *dlfb;1739	struct fb_info *info;1740	int i;1741 1742	dlfb = usb_get_intfdata(intf);1743	info = dlfb->info;1744 1745	dev_dbg(&intf->dev, "USB disconnect starting\n");1746 1747	/* we virtualize until all fb clients release. Then we free */1748	dlfb->virtualized = true;1749 1750	/* When non-active we'll update virtual framebuffer, but no new urbs */1751	atomic_set(&dlfb->usb_active, 0);1752 1753	/* this function will wait for all in-flight urbs to complete */1754	dlfb_free_urb_list(dlfb);1755 1756	/* remove udlfb's sysfs interfaces */1757	for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++)1758		device_remove_file(info->dev, &fb_device_attrs[i]);1759	device_remove_bin_file(info->dev, &edid_attr);1760 1761	unregister_framebuffer(info);1762}1763 1764static struct usb_driver dlfb_driver = {1765	.name = "udlfb",1766	.probe = dlfb_usb_probe,1767	.disconnect = dlfb_usb_disconnect,1768	.id_table = id_table,1769};1770 1771module_usb_driver(dlfb_driver);1772 1773static void dlfb_urb_completion(struct urb *urb)1774{1775	struct urb_node *unode = urb->context;1776	struct dlfb_data *dlfb = unode->dlfb;1777	unsigned long flags;1778 1779	switch (urb->status) {1780	case 0:1781		/* success */1782		break;1783	case -ECONNRESET:1784	case -ENOENT:1785	case -ESHUTDOWN:1786		/* sync/async unlink faults aren't errors */1787		break;1788	default:1789		dev_err(&dlfb->udev->dev,1790			"%s - nonzero write bulk status received: %d\n",1791			__func__, urb->status);1792		atomic_set(&dlfb->lost_pixels, 1);1793		break;1794	}1795 1796	urb->transfer_buffer_length = dlfb->urbs.size; /* reset to actual */1797 1798	spin_lock_irqsave(&dlfb->urbs.lock, flags);1799	list_add_tail(&unode->entry, &dlfb->urbs.list);1800	dlfb->urbs.available++;1801	spin_unlock_irqrestore(&dlfb->urbs.lock, flags);1802 1803	up(&dlfb->urbs.limit_sem);1804}1805 1806static void dlfb_free_urb_list(struct dlfb_data *dlfb)1807{1808	int count = dlfb->urbs.count;1809	struct list_head *node;1810	struct urb_node *unode;1811	struct urb *urb;1812 1813	/* keep waiting and freeing, until we've got 'em all */1814	while (count--) {1815		down(&dlfb->urbs.limit_sem);1816 1817		spin_lock_irq(&dlfb->urbs.lock);1818 1819		node = dlfb->urbs.list.next; /* have reserved one with sem */1820		list_del_init(node);1821 1822		spin_unlock_irq(&dlfb->urbs.lock);1823 1824		unode = list_entry(node, struct urb_node, entry);1825		urb = unode->urb;1826 1827		/* Free each separately allocated piece */1828		usb_free_coherent(urb->dev, dlfb->urbs.size,1829				  urb->transfer_buffer, urb->transfer_dma);1830		usb_free_urb(urb);1831		kfree(node);1832	}1833 1834	dlfb->urbs.count = 0;1835}1836 1837static int dlfb_alloc_urb_list(struct dlfb_data *dlfb, int count, size_t size)1838{1839	struct urb *urb;1840	struct urb_node *unode;1841	char *buf;1842	size_t wanted_size = count * size;1843 1844	spin_lock_init(&dlfb->urbs.lock);1845 1846retry:1847	dlfb->urbs.size = size;1848	INIT_LIST_HEAD(&dlfb->urbs.list);1849 1850	sema_init(&dlfb->urbs.limit_sem, 0);1851	dlfb->urbs.count = 0;1852	dlfb->urbs.available = 0;1853 1854	while (dlfb->urbs.count * size < wanted_size) {1855		unode = kzalloc(sizeof(*unode), GFP_KERNEL);1856		if (!unode)1857			break;1858		unode->dlfb = dlfb;1859 1860		urb = usb_alloc_urb(0, GFP_KERNEL);1861		if (!urb) {1862			kfree(unode);1863			break;1864		}1865		unode->urb = urb;1866 1867		buf = usb_alloc_coherent(dlfb->udev, size, GFP_KERNEL,1868					 &urb->transfer_dma);1869		if (!buf) {1870			kfree(unode);1871			usb_free_urb(urb);1872			if (size > PAGE_SIZE) {1873				size /= 2;1874				dlfb_free_urb_list(dlfb);1875				goto retry;1876			}1877			break;1878		}1879 1880		/* urb->transfer_buffer_length set to actual before submit */1881		usb_fill_bulk_urb(urb, dlfb->udev,1882			usb_sndbulkpipe(dlfb->udev, OUT_EP_NUM),1883			buf, size, dlfb_urb_completion, unode);1884		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;1885 1886		list_add_tail(&unode->entry, &dlfb->urbs.list);1887 1888		up(&dlfb->urbs.limit_sem);1889		dlfb->urbs.count++;1890		dlfb->urbs.available++;1891	}1892 1893	return dlfb->urbs.count;1894}1895 1896static struct urb *dlfb_get_urb(struct dlfb_data *dlfb)1897{1898	int ret;1899	struct list_head *entry;1900	struct urb_node *unode;1901 1902	/* Wait for an in-flight buffer to complete and get re-queued */1903	ret = down_timeout(&dlfb->urbs.limit_sem, GET_URB_TIMEOUT);1904	if (ret) {1905		atomic_set(&dlfb->lost_pixels, 1);1906		dev_warn(&dlfb->udev->dev,1907			 "wait for urb interrupted: %d available: %d\n",1908			 ret, dlfb->urbs.available);1909		return NULL;1910	}1911 1912	spin_lock_irq(&dlfb->urbs.lock);1913 1914	BUG_ON(list_empty(&dlfb->urbs.list)); /* reserved one with limit_sem */1915	entry = dlfb->urbs.list.next;1916	list_del_init(entry);1917	dlfb->urbs.available--;1918 1919	spin_unlock_irq(&dlfb->urbs.lock);1920 1921	unode = list_entry(entry, struct urb_node, entry);1922	return unode->urb;1923}1924 1925static int dlfb_submit_urb(struct dlfb_data *dlfb, struct urb *urb, size_t len)1926{1927	int ret;1928 1929	BUG_ON(len > dlfb->urbs.size);1930 1931	urb->transfer_buffer_length = len; /* set to actual payload len */1932	ret = usb_submit_urb(urb, GFP_KERNEL);1933	if (ret) {1934		dlfb_urb_completion(urb); /* because no one else will */1935		atomic_set(&dlfb->lost_pixels, 1);1936		dev_err(&dlfb->udev->dev, "submit urb error: %d\n", ret);1937	}1938	return ret;1939}1940 1941module_param(console, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);1942MODULE_PARM_DESC(console, "Allow fbcon to open framebuffer");1943 1944module_param(fb_defio, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);1945MODULE_PARM_DESC(fb_defio, "Page fault detection of mmap writes");1946 1947module_param(shadow, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);1948MODULE_PARM_DESC(shadow, "Shadow vid mem. Disable to save mem but lose perf");1949 1950module_param(pixel_limit, int, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP);1951MODULE_PARM_DESC(pixel_limit, "Force limit on max mode (in x*y pixels)");1952 1953MODULE_AUTHOR("Roberto De Ioris <roberto@unbit.it>, "1954	      "Jaya Kumar <jayakumar.lkml@gmail.com>, "1955	      "Bernie Thompson <bernie@plugable.com>");1956MODULE_DESCRIPTION("DisplayLink kernel framebuffer driver");1957MODULE_LICENSE("GPL");1958 1959