bfin-t350mcqb-fb.c

Linux环境下视频显示卡设备的驱动程序源代码

/*
 * File:         drivers/video/bfin-t350mcqb-fb.c
 * Based on:
 * Author:       Michael Hennerich <[e-mail]>
 *
 * Created:
 * Description:  Blackfin LCD Framebufer driver
 *
 *
 * Modified:
 *               Copyright 2004-2007 Analog Devices Inc.
 *
 * Bugs:         Enter bugs at http://blackfin.uclinux.org/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see the file COPYING, or write
 * to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/backlight.h>
#include <linux/lcd.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>

#include <asm/blackfin.h>
#include <asm/irq.h>
#include <asm/dma-mapping.h>
#include <asm/dma.h>
#include <asm/portmux.h>
#include <asm/gptimers.h>

#define NO_BL_SUPPORT

#define LCD_X_RES		320	/* Horizontal Resolution */
#define LCD_Y_RES		240	/* Vertical Resolution */
#define LCD_BPP			24	/* Bit Per Pixel */

#define	DMA_BUS_SIZE		16
#define	LCD_CLK         	(12*1000*1000)	/* 12MHz */

#define CLOCKS_PER_PIX		3

	/*
	 * HS and VS timing parameters (all in number of PPI clk ticks)
	 */

#define U_LINE		1				/* Blanking Lines */

#define H_ACTPIX	(LCD_X_RES * CLOCKS_PER_PIX)	/* active horizontal pixel */
#define H_PERIOD	(408 * CLOCKS_PER_PIX)		/* HS period */
#define H_PULSE		90				/* HS pulse width */
#define H_START		204				/* first valid pixel */

#define	V_LINES		(LCD_Y_RES + U_LINE)		/* total vertical lines */
#define V_PULSE		(3 * H_PERIOD)			/* VS pulse width (1-5 H_PERIODs) */
#define V_PERIOD	(H_PERIOD * V_LINES)		/* VS period */

#define ACTIVE_VIDEO_MEM_OFFSET	(U_LINE * H_ACTPIX)

#define BFIN_LCD_NBR_PALETTE_ENTRIES	256

#define DRIVER_NAME "bfin-t350mcqb"
static char driver_name[] = DRIVER_NAME;

struct bfin_t350mcqbfb_info {
	struct fb_info *fb;
	struct device *dev;
	unsigned char *fb_buffer;	/* RGB Buffer */
	dma_addr_t dma_handle;
	int lq043_mmap;
	int lq043_open_cnt;
	int irq;
	spinlock_t lock;	/* lock */
	u32 pseudo_pal[16];
};

static int nocursor;
module_param(nocursor, int, 0644);
MODULE_PARM_DESC(nocursor, "cursor enable/disable");

#define PPI_TX_MODE		0x2
#define PPI_XFER_TYPE_11	0xC
#define PPI_PORT_CFG_01		0x10
#define PPI_PACK_EN		0x80
#define PPI_POLS_1		0x8000

static void bfin_t350mcqb_config_ppi(struct bfin_t350mcqbfb_info *fbi)
{
	bfin_write_PPI_DELAY(H_START);
	bfin_write_PPI_COUNT(H_ACTPIX-1);
	bfin_write_PPI_FRAME(V_LINES);

	bfin_write_PPI_CONTROL(PPI_TX_MODE |	   /* output mode , PORT_DIR */
				PPI_XFER_TYPE_11 | /* sync mode XFR_TYPE */
				PPI_PORT_CFG_01 |  /* two frame sync PORT_CFG */
				PPI_PACK_EN |	   /* packing enabled PACK_EN */
				PPI_POLS_1);	   /* faling edge syncs POLS */
}

static inline void bfin_t350mcqb_disable_ppi(void)
{
	bfin_write_PPI_CONTROL(bfin_read_PPI_CONTROL() & ~PORT_EN);
}

static inline void bfin_t350mcqb_enable_ppi(void)
{
	bfin_write_PPI_CONTROL(bfin_read_PPI_CONTROL() | PORT_EN);
}

static void bfin_t350mcqb_start_timers(void)
{
	unsigned long flags;

	local_irq_save(flags);
		enable_gptimers(TIMER1bit);
		enable_gptimers(TIMER0bit);
	local_irq_restore(flags);
}

static void bfin_t350mcqb_stop_timers(void)
{
	disable_gptimers(TIMER0bit | TIMER1bit);

	set_gptimer_status(0, TIMER_STATUS_TRUN0 | TIMER_STATUS_TRUN1 |
				TIMER_STATUS_TIMIL0 | TIMER_STATUS_TIMIL1 |
				 TIMER_STATUS_TOVF0 | TIMER_STATUS_TOVF1);

}

static void bfin_t350mcqb_init_timers(void)
{

	bfin_t350mcqb_stop_timers();

	set_gptimer_period(TIMER0_id, H_PERIOD);
	set_gptimer_pwidth(TIMER0_id, H_PULSE);
	set_gptimer_config(TIMER0_id, TIMER_MODE_PWM | TIMER_PERIOD_CNT |
				      TIMER_TIN_SEL | TIMER_CLK_SEL|
				      TIMER_EMU_RUN);

	set_gptimer_period(TIMER1_id, V_PERIOD);
	set_gptimer_pwidth(TIMER1_id, V_PULSE);
	set_gptimer_config(TIMER1_id, TIMER_MODE_PWM | TIMER_PERIOD_CNT |
				      TIMER_TIN_SEL | TIMER_CLK_SEL |
				      TIMER_EMU_RUN);

}

static void bfin_t350mcqb_config_dma(struct bfin_t350mcqbfb_info *fbi)
{

	set_dma_config(CH_PPI,
		       set_bfin_dma_config(DIR_READ, DMA_FLOW_AUTO,
					   INTR_DISABLE, DIMENSION_2D,
					   DATA_SIZE_16,
					   DMA_NOSYNC_KEEP_DMA_BUF));
	set_dma_x_count(CH_PPI, (LCD_X_RES * LCD_BPP) / DMA_BUS_SIZE);
	set_dma_x_modify(CH_PPI, DMA_BUS_SIZE / 8);
	set_dma_y_count(CH_PPI, V_LINES);

	set_dma_y_modify(CH_PPI, DMA_BUS_SIZE / 8);
	set_dma_start_addr(CH_PPI, (unsigned long)fbi->fb_buffer);

}

static	u16 ppi0_req_8[] = {P_PPI0_CLK, P_PPI0_FS1, P_PPI0_FS2,
			    P_PPI0_D0, P_PPI0_D1, P_PPI0_D2,
			    P_PPI0_D3, P_PPI0_D4, P_PPI0_D5,
			    P_PPI0_D6, P_PPI0_D7, 0};

static int bfin_t350mcqb_request_ports(int action)
{
	if (action) {
		if (peripheral_request_list(ppi0_req_8, DRIVER_NAME)) {
			printk(KERN_ERR "Requesting Peripherals faild\n");
			return -EFAULT;
		}
	} else
		peripheral_free_list(ppi0_req_8);

	return 0;
}

static int bfin_t350mcqb_fb_open(struct fb_info *info, int user)
{
	struct bfin_t350mcqbfb_info *fbi = info->par;

	spin_lock(&fbi->lock);
	fbi->lq043_open_cnt++;

	if (fbi->lq043_open_cnt <= 1) {

		bfin_t350mcqb_disable_ppi();
		SSYNC();

		bfin_t350mcqb_config_dma(fbi);
		bfin_t350mcqb_config_ppi(fbi);
		bfin_t350mcqb_init_timers();

		/* start dma */
		enable_dma(CH_PPI);
		bfin_t350mcqb_enable_ppi();
		bfin_t350mcqb_start_timers();
	}

	spin_unlock(&fbi->lock);

	return 0;
}

static int bfin_t350mcqb_fb_release(struct fb_info *info, int user)
{
	struct bfin_t350mcqbfb_info *fbi = info->par;

	spin_lock(&fbi->lock);

	fbi->lq043_open_cnt--;
	fbi->lq043_mmap = 0;

	if (fbi->lq043_open_cnt <= 0) {
		bfin_t350mcqb_disable_ppi();
		SSYNC();
		disable_dma(CH_PPI);
		bfin_t350mcqb_stop_timers();
		memset(fbi->fb_buffer, 0, info->fix.smem_len);
	}

	spin_unlock(&fbi->lock);

	return 0;
}

static int bfin_t350mcqb_fb_check_var(struct fb_var_screeninfo *var,
				   struct fb_info *info)
{

	switch (var->bits_per_pixel) {
	case 24:/* TRUECOLOUR, 16m */
		var->red.offset = 0;
		var->green.offset = 8;
		var->blue.offset = 16;
		var->red.length = var->green.length = var->blue.length = 8;
		var->transp.offset = 0;
		var->transp.length = 0;
		var->transp.msb_right = 0;
		var->red.msb_right = 0;
		var->green.msb_right = 0;
		var->blue.msb_right = 0;
		break;
	default:
		pr_debug("%s: depth not supported: %u BPP\n", __func__,
			 var->bits_per_pixel);
		return -EINVAL;
	}

	if (info->var.xres != var->xres || info->var.yres != var->yres ||
	    info->var.xres_virtual != var->xres_virtual ||
	    info->var.yres_virtual != var->yres_virtual) {
		pr_debug("%s: Resolution not supported: X%u x Y%u \n",
			 __func__, var->xres, var->yres);
		return -EINVAL;
	}

	/*
	 *  Memory limit
	 */

	if ((info->fix.line_length * var->yres_virtual) > info->fix.smem_len) {
		pr_debug("%s: Memory Limit requested yres_virtual = %u\n",
			 __func__, var->yres_virtual);
		return -ENOMEM;
	}

	return 0;
}

static int bfin_t350mcqb_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
{
	struct bfin_t350mcqbfb_info *fbi = info->par;

	if (fbi->lq043_mmap)
		return -1;

	spin_lock(&fbi->lock);
	fbi->lq043_mmap = 1;
	spin_unlock(&fbi->lock);

	vma->vm_start = (unsigned long)(fbi->fb_buffer + ACTIVE_VIDEO_MEM_OFFSET);

	vma->vm_end = vma->vm_start + info->fix.smem_len;
	/* For those who don't understand how mmap works, go read
	 *   Documentation/nommu-mmap.txt.
	 * For those that do, you will know that the VM_MAYSHARE flag
	 * must be set in the vma->vm_flags structure on noMMU
	 *   Other flags can be set, and are documented in
	 *   include/linux/mm.h
	 */
	vma->vm_flags |= VM_MAYSHARE | VM_SHARED;

	return 0;
}

int bfin_t350mcqb_fb_cursor(struct fb_info *info, struct fb_cursor *cursor)
{
	if (nocursor)
		return 0;
	else
		return -EINVAL;	/* just to force soft_cursor() call */
}

static int bfin_t350mcqb_fb_setcolreg(u_int regno, u_int red, u_int green,
				   u_int blue, u_int transp,
				   struct fb_info *info)
{
	if (regno >= BFIN_LCD_NBR_PALETTE_ENTRIES)
		return -EINVAL;

	if (info->var.grayscale) {
		/* grayscale = 0.30*R + 0.59*G + 0.11*B */
		red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
	}

	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {

		u32 value;
		/* Place color in the pseudopalette */