metronomefb.c

Linux环境下视频显示卡设备的驱动程序源代码

/*
 * linux/drivers/video/metronomefb.c -- FB driver for Metronome controller
 *
 * Copyright (C) 2008, Jaya Kumar
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file COPYING in the main directory of this archive for
 * more details.
 *
 * Layout is based on skeletonfb.c by James Simmons and Geert Uytterhoeven.
 *
 * This work was made possible by help and equipment support from E-Ink
 * Corporation. http://support.eink.com/community
 *
 * This driver is written to be used with the Metronome display controller.
 * It is intended to be architecture independent. A board specific driver
 * must be used to perform all the physical IO interactions. An example
 * is provided as am200epd.c
 *
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/list.h>
#include <linux/firmware.h>
#include <linux/dma-mapping.h>
#include <linux/uaccess.h>
#include <linux/irq.h>

#include <video/metronomefb.h>

#include <asm/unaligned.h>

/* Display specific information */
#define DPY_W 832
#define DPY_H 622

static int user_wfm_size;

/* frame differs from image. frame includes non-visible pixels */
struct epd_frame {
	int fw; /* frame width */
	int fh; /* frame height */
	u16 config[4];
	int wfm_size;
};

static struct epd_frame epd_frame_table[] = {
	{
		.fw = 832,
		.fh = 622,
		.config = {
			15 /* sdlew */
			| 2 << 8 /* sdosz */
			| 0 << 11 /* sdor */
			| 0 << 12 /* sdces */
			| 0 << 15, /* sdcer */
			42 /* gdspl */
			| 1 << 8 /* gdr1 */
			| 1 << 9 /* sdshr */
			| 0 << 15, /* gdspp */
			18 /* gdspw */
			| 0 << 15, /* dispc */
			599 /* vdlc */
			| 0 << 11 /* dsi */
			| 0 << 12, /* dsic */
		},
		.wfm_size = 47001,
	},
	{
		.fw = 1088,
		.fh = 791,
		.config = {
			0x0104,
			0x031f,
			0x0088,
			0x02ff,
		},
		.wfm_size = 46770,
	},
	{
		.fw = 1200,
		.fh = 842,
		.config = {
			0x0101,
			0x030e,
			0x0012,
			0x0280,
		},
		.wfm_size = 46770,
	},
};

static struct fb_fix_screeninfo metronomefb_fix __devinitdata = {
	.id =		"metronomefb",
	.type =		FB_TYPE_PACKED_PIXELS,
	.visual =	FB_VISUAL_STATIC_PSEUDOCOLOR,
	.xpanstep =	0,
	.ypanstep =	0,
	.ywrapstep =	0,
	.line_length =	DPY_W,
	.accel =	FB_ACCEL_NONE,
};

static struct fb_var_screeninfo metronomefb_var __devinitdata = {
	.xres		= DPY_W,
	.yres		= DPY_H,
	.xres_virtual	= DPY_W,
	.yres_virtual	= DPY_H,
	.bits_per_pixel	= 8,
	.grayscale	= 1,
	.nonstd		= 1,
	.red =		{ 4, 3, 0 },
	.green =	{ 0, 0, 0 },
	.blue =		{ 0, 0, 0 },
	.transp =	{ 0, 0, 0 },
};

/* the waveform structure that is coming from userspace firmware */
struct waveform_hdr {
	u8 stuff[32];

	u8 wmta[3];
	u8 fvsn;

	u8 luts;
	u8 mc;
	u8 trc;
	u8 stuff3;

	u8 endb;
	u8 swtb;
	u8 stuff2a[2];

	u8 stuff2b[3];
	u8 wfm_cs;
} __attribute__ ((packed));

/* main metronomefb functions */
static u8 calc_cksum(int start, int end, u8 *mem)
{
	u8 tmp = 0;
	int i;

	for (i = start; i < end; i++)
		tmp += mem[i];

	return tmp;
}

static u16 calc_img_cksum(u16 *start, int length)
{
	u16 tmp = 0;

	while (length--)
		tmp += *start++;

	return tmp;
}

/* here we decode the incoming waveform file and populate metromem */
static int __devinit load_waveform(u8 *mem, size_t size, int m, int t,
				struct metronomefb_par *par)
{
	int tta;
	int wmta;
	int trn = 0;
	int i;
	unsigned char v;
	u8 cksum;
	int cksum_idx;
	int wfm_idx, owfm_idx;
	int mem_idx = 0;
	struct waveform_hdr *wfm_hdr;
	u8 *metromem = par->metromem_wfm;
	struct device *dev = par->info->dev;

	if (user_wfm_size)
		epd_frame_table[par->dt].wfm_size = user_wfm_size;

	if (size != epd_frame_table[par->dt].wfm_size) {
		dev_err(dev, "Error: unexpected size %Zd != %d\n", size,
					epd_frame_table[par->dt].wfm_size);
		return -EINVAL;
	}

	wfm_hdr = (struct waveform_hdr *) mem;

	if (wfm_hdr->fvsn != 1) {
		dev_err(dev, "Error: bad fvsn %x\n", wfm_hdr->fvsn);
		return -EINVAL;
	}
	if (wfm_hdr->luts != 0) {
		dev_err(dev, "Error: bad luts %x\n", wfm_hdr->luts);
		return -EINVAL;
	}
	cksum = calc_cksum(32, 47, mem);
	if (cksum != wfm_hdr->wfm_cs) {
		dev_err(dev, "Error: bad cksum %x != %x\n", cksum,
					wfm_hdr->wfm_cs);
		return -EINVAL;
	}
	wfm_hdr->mc += 1;
	wfm_hdr->trc += 1;
	for (i = 0; i < 5; i++) {
		if (*(wfm_hdr->stuff2a + i) != 0) {
			dev_err(dev, "Error: unexpected value in padding\n");
			return -EINVAL;
		}
	}

	/* calculating trn. trn is something used to index into
	the waveform. presumably selecting the right one for the
	desired temperature. it works out the offset of the first
	v that exceeds the specified temperature */
	if ((sizeof(*wfm_hdr) + wfm_hdr->trc) > size)
		return -EINVAL;

	for (i = sizeof(*wfm_hdr); i <= sizeof(*wfm_hdr) + wfm_hdr->trc; i++) {
		if (mem[i] > t) {
			trn = i - sizeof(*wfm_hdr) - 1;
			break;
		}
	}

	/* check temperature range table checksum */
	cksum_idx = sizeof(*wfm_hdr) + wfm_hdr->trc + 1;
	if (cksum_idx > size)
		return -EINVAL;
	cksum = calc_cksum(sizeof(*wfm_hdr), cksum_idx, mem);
	if (cksum != mem[cksum_idx]) {
		dev_err(dev, "Error: bad temperature range table cksum"
				" %x != %x\n", cksum, mem[cksum_idx]);
		return -EINVAL;
	}

	/* check waveform mode table address checksum */
	wmta = get_unaligned_le32(wfm_hdr->wmta) & 0x00FFFFFF;
	cksum_idx = wmta + m*4 + 3;
	if (cksum_idx > size)
		return -EINVAL;
	cksum = calc_cksum(cksum_idx - 3, cksum_idx, mem);
	if (cksum != mem[cksum_idx]) {
		dev_err(dev, "Error: bad mode table address cksum"
				" %x != %x\n", cksum, mem[cksum_idx]);
		return -EINVAL;
	}

	/* check waveform temperature table address checksum */
	tta = get_unaligned_le32(mem + wmta + m * 4) & 0x00FFFFFF;
	cksum_idx = tta + trn*4 + 3;
	if (cksum_idx > size)
		return -EINVAL;
	cksum = calc_cksum(cksum_idx - 3, cksum_idx, mem);
	if (cksum != mem[cksum_idx]) {
		dev_err(dev, "Error: bad temperature table address cksum"
			" %x != %x\n", cksum, mem[cksum_idx]);
		return -EINVAL;
	}

	/* here we do the real work of putting the waveform into the
	metromem buffer. this does runlength decoding of the waveform */
	wfm_idx = get_unaligned_le32(mem + tta + trn * 4) & 0x00FFFFFF;
	owfm_idx = wfm_idx;
	if (wfm_idx > size)
		return -EINVAL;
	while (wfm_idx < size) {
		unsigned char rl;
		v = mem[wfm_idx++];
		if (v == wfm_hdr->swtb) {
			while (((v = mem[wfm_idx++]) != wfm_hdr->swtb) &&
				wfm_idx < size)
				metromem[mem_idx++] = v;

			continue;
		}

		if (v == wfm_hdr->endb)
			break;

		rl = mem[wfm_idx++];
		for (i = 0; i <= rl; i++)
			metromem[mem_idx++] = v;
	}

	cksum_idx = wfm_idx;
	if (cksum_idx > size)
		return -EINVAL;
	cksum = calc_cksum(owfm_idx, cksum_idx, mem);
	if (cksum != mem[cksum_idx]) {
		dev_err(dev, "Error: bad waveform data cksum"
				" %x != %x\n", cksum, mem[cksum_idx]);
		return -EINVAL;
	}
	par->frame_count = (mem_idx/64);

	return 0;
}

static int metronome_display_cmd(struct metronomefb_par *par)
{
	int i;
	u16 cs;
	u16 opcode;
	static u8 borderval;

	/* setup display command
	we can't immediately set the opcode since the controller
	will try parse the command before we've set it all up
	so we just set cs here and set the opcode at the end */

	if (par->metromem_cmd->opcode == 0xCC40)
		opcode = cs = 0xCC41;
	else
		opcode = cs = 0xCC40;

	/* set the args ( 2 bytes ) for display */
	i = 0;
	par->metromem_cmd->args[i] = 	1 << 3 /* border update */
					| ((borderval++ % 4) & 0x0F) << 4
					| (par->frame_count - 1) << 8;
	cs += par->metromem_cmd->args[i++];

	/* the rest are 0 */
	memset((u8 *) (par->metromem_cmd->args + i), 0, (32-i)*2);

	par->metromem_cmd->csum = cs;
	par->metromem_cmd->opcode = opcode; /* display cmd */

	return par->board->met_wait_event_intr(par);
}

static int __devinit metronome_powerup_cmd(struct metronomefb_par *par)
{
	int i;
	u16 cs;

	/* setup power up command */
	par->metromem_cmd->opcode = 0x1234; /* pwr up pseudo cmd */
	cs = par->metromem_cmd->opcode;

	/* set pwr1,2,3 to 1024 */
	for (i = 0; i < 3; i++) {
		par->metromem_cmd->args[i] = 1024;
		cs += par->metromem_cmd->args[i];
	}

	/* the rest are 0 */
	memset((u8 *) (par->metromem_cmd->args + i), 0, (32-i)*2);

	par->metromem_cmd->csum = cs;

	msleep(1);
	par->board->set_rst(par, 1);

	msleep(1);
	par->board->set_stdby(par, 1);

	return par->board->met_wait_event(par);
}

static int __devinit metronome_config_cmd(struct metronomefb_par *par)
{
	/* setup config command
	we can't immediately set the opcode since the controller
	will try parse the command before we've set it all up */

	memcpy(par->metromem_cmd->args, epd_frame_table[par->dt].config,
		sizeof(epd_frame_table[par->dt].config));
	/* the rest are 0 */
	memset((u8 *) (par->metromem_cmd->args + 4), 0, (32-4)*2);

	par->metromem_cmd->csum = 0xCC10;
	par->metromem_cmd->csum += calc_img_cksum(par->metromem_cmd->args, 4);
	par->metromem_cmd->opcode = 0xCC10; /* config cmd */

	return par->board->met_wait_event(par);
}

static int __devinit metronome_init_cmd(struct metronomefb_par *par)
{
	int i;
	u16 cs;

	/* setup init command
	we can't immediately set the opcode since the controller
	will try parse the command before we've set it all up
	so we just set cs here and set the opcode at the end */