sa1100fb.c

Linux环境下视频显示卡设备的驱动程序源代码

	}

	DPRINTK("DBAR1 = 0x%08x\n", DBAR1);
	DPRINTK("DBAR2 = 0x%08x\n", DBAR2);
	DPRINTK("LCCR0 = 0x%08x\n", LCCR0);
	DPRINTK("LCCR1 = 0x%08x\n", LCCR1);
	DPRINTK("LCCR2 = 0x%08x\n", LCCR2);
	DPRINTK("LCCR3 = 0x%08x\n", LCCR3);
}

static void sa1100fb_disable_controller(struct sa1100fb_info *fbi)
{
	DECLARE_WAITQUEUE(wait, current);

	DPRINTK("Disabling LCD controller\n");

	if (machine_is_shannon()) {
		GPCR |= SHANNON_GPIO_DISP_EN;
	}	

	set_current_state(TASK_UNINTERRUPTIBLE);
	add_wait_queue(&fbi->ctrlr_wait, &wait);

	LCSR = 0xffffffff;	/* Clear LCD Status Register */
	LCCR0 &= ~LCCR0_LDM;	/* Enable LCD Disable Done Interrupt */
	LCCR0 &= ~LCCR0_LEN;	/* Disable LCD Controller */

	schedule_timeout(20 * HZ / 1000);
	remove_wait_queue(&fbi->ctrlr_wait, &wait);
}

/*
 *  sa1100fb_handle_irq: Handle 'LCD DONE' interrupts.
 */
static irqreturn_t sa1100fb_handle_irq(int irq, void *dev_id)
{
	struct sa1100fb_info *fbi = dev_id;
	unsigned int lcsr = LCSR;

	if (lcsr & LCSR_LDD) {
		LCCR0 |= LCCR0_LDM;
		wake_up(&fbi->ctrlr_wait);
	}

	LCSR = lcsr;
	return IRQ_HANDLED;
}

/*
 * This function must be called from task context only, since it will
 * sleep when disabling the LCD controller, or if we get two contending
 * processes trying to alter state.
 */
static void set_ctrlr_state(struct sa1100fb_info *fbi, u_int state)
{
	u_int old_state;

	mutex_lock(&fbi->ctrlr_lock);

	old_state = fbi->state;

	/*
	 * Hack around fbcon initialisation.
	 */
	if (old_state == C_STARTUP && state == C_REENABLE)
		state = C_ENABLE;

	switch (state) {
	case C_DISABLE_CLKCHANGE:
		/*
		 * Disable controller for clock change.  If the
		 * controller is already disabled, then do nothing.
		 */
		if (old_state != C_DISABLE && old_state != C_DISABLE_PM) {
			fbi->state = state;
			sa1100fb_disable_controller(fbi);
		}
		break;

	case C_DISABLE_PM:
	case C_DISABLE:
		/*
		 * Disable controller
		 */
		if (old_state != C_DISABLE) {
			fbi->state = state;

			__sa1100fb_backlight_power(fbi, 0);
			if (old_state != C_DISABLE_CLKCHANGE)
				sa1100fb_disable_controller(fbi);
			__sa1100fb_lcd_power(fbi, 0);
		}
		break;

	case C_ENABLE_CLKCHANGE:
		/*
		 * Enable the controller after clock change.  Only
		 * do this if we were disabled for the clock change.
		 */
		if (old_state == C_DISABLE_CLKCHANGE) {
			fbi->state = C_ENABLE;
			sa1100fb_enable_controller(fbi);
		}
		break;

	case C_REENABLE:
		/*
		 * Re-enable the controller only if it was already
		 * enabled.  This is so we reprogram the control
		 * registers.
		 */
		if (old_state == C_ENABLE) {
			sa1100fb_disable_controller(fbi);
			sa1100fb_setup_gpio(fbi);
			sa1100fb_enable_controller(fbi);
		}
		break;

	case C_ENABLE_PM:
		/*
		 * Re-enable the controller after PM.  This is not
		 * perfect - think about the case where we were doing
		 * a clock change, and we suspended half-way through.
		 */
		if (old_state != C_DISABLE_PM)
			break;
		/* fall through */

	case C_ENABLE:
		/*
		 * Power up the LCD screen, enable controller, and
		 * turn on the backlight.
		 */
		if (old_state != C_ENABLE) {
			fbi->state = C_ENABLE;
			sa1100fb_setup_gpio(fbi);
			__sa1100fb_lcd_power(fbi, 1);
			sa1100fb_enable_controller(fbi);
			__sa1100fb_backlight_power(fbi, 1);
		}
		break;
	}
	mutex_unlock(&fbi->ctrlr_lock);
}

/*
 * Our LCD controller task (which is called when we blank or unblank)
 * via keventd.
 */
static void sa1100fb_task(struct work_struct *w)
{
	struct sa1100fb_info *fbi = container_of(w, struct sa1100fb_info, task);
	u_int state = xchg(&fbi->task_state, -1);

	set_ctrlr_state(fbi, state);
}

#ifdef CONFIG_CPU_FREQ
/*
 * Calculate the minimum DMA period over all displays that we own.
 * This, together with the SDRAM bandwidth defines the slowest CPU
 * frequency that can be selected.
 */
static unsigned int sa1100fb_min_dma_period(struct sa1100fb_info *fbi)
{
#if 0
	unsigned int min_period = (unsigned int)-1;
	int i;

	for (i = 0; i < MAX_NR_CONSOLES; i++) {
		struct display *disp = &fb_display[i];
		unsigned int period;

		/*
		 * Do we own this display?
		 */
		if (disp->fb_info != &fbi->fb)
			continue;

		/*
		 * Ok, calculate its DMA period
		 */
		period = sa1100fb_display_dma_period(&disp->var);
		if (period < min_period)
			min_period = period;
	}

	return min_period;
#else
	/*
	 * FIXME: we need to verify _all_ consoles.
	 */
	return sa1100fb_display_dma_period(&fbi->fb.var);
#endif
}

/*
 * CPU clock speed change handler.  We need to adjust the LCD timing
 * parameters when the CPU clock is adjusted by the power management
 * subsystem.
 */
static int
sa1100fb_freq_transition(struct notifier_block *nb, unsigned long val,
			 void *data)
{
	struct sa1100fb_info *fbi = TO_INF(nb, freq_transition);
	struct cpufreq_freqs *f = data;
	u_int pcd;

	switch (val) {
	case CPUFREQ_PRECHANGE:
		set_ctrlr_state(fbi, C_DISABLE_CLKCHANGE);
		break;

	case CPUFREQ_POSTCHANGE:
		pcd = get_pcd(fbi->fb.var.pixclock, f->new);
		fbi->reg_lccr3 = (fbi->reg_lccr3 & ~0xff) | LCCR3_PixClkDiv(pcd);
		set_ctrlr_state(fbi, C_ENABLE_CLKCHANGE);
		break;
	}
	return 0;
}

static int
sa1100fb_freq_policy(struct notifier_block *nb, unsigned long val,
		     void *data)
{
	struct sa1100fb_info *fbi = TO_INF(nb, freq_policy);
	struct cpufreq_policy *policy = data;

	switch (val) {
	case CPUFREQ_ADJUST:
	case CPUFREQ_INCOMPATIBLE:
		printk(KERN_DEBUG "min dma period: %d ps, "
			"new clock %d kHz\n", sa1100fb_min_dma_period(fbi),
			policy->max);
		/* todo: fill in min/max values */
		break;
	case CPUFREQ_NOTIFY:
		do {} while(0);
		/* todo: panic if min/max values aren't fulfilled 
		 * [can't really happen unless there's a bug in the
		 * CPU policy verififcation process *
		 */
		break;
	}
	return 0;
}
#endif

#ifdef CONFIG_PM
/*
 * Power management hooks.  Note that we won't be called from IRQ context,
 * unlike the blank functions above, so we may sleep.
 */
static int sa1100fb_suspend(struct platform_device *dev, pm_message_t state)
{
	struct sa1100fb_info *fbi = platform_get_drvdata(dev);

	set_ctrlr_state(fbi, C_DISABLE_PM);
	return 0;
}

static int sa1100fb_resume(struct platform_device *dev)
{
	struct sa1100fb_info *fbi = platform_get_drvdata(dev);

	set_ctrlr_state(fbi, C_ENABLE_PM);
	return 0;
}
#else
#define sa1100fb_suspend	NULL
#define sa1100fb_resume		NULL
#endif

/*
 * sa1100fb_map_video_memory():
 *      Allocates the DRAM memory for the frame buffer.  This buffer is  
 *	remapped into a non-cached, non-buffered, memory region to  
 *      allow palette and pixel writes to occur without flushing the 
 *      cache.  Once this area is remapped, all virtual memory
 *      access to the video memory should occur at the new region.
 */
static int __init sa1100fb_map_video_memory(struct sa1100fb_info *fbi)
{
	/*
	 * We reserve one page for the palette, plus the size
	 * of the framebuffer.
	 */
	fbi->map_size = PAGE_ALIGN(fbi->fb.fix.smem_len + PAGE_SIZE);
	fbi->map_cpu = dma_alloc_writecombine(fbi->dev, fbi->map_size,
					      &fbi->map_dma, GFP_KERNEL);

	if (fbi->map_cpu) {
		fbi->fb.screen_base = fbi->map_cpu + PAGE_SIZE;
		fbi->screen_dma = fbi->map_dma + PAGE_SIZE;
		/*
		 * FIXME: this is actually the wrong thing to place in
		 * smem_start.  But fbdev suffers from the problem that
		 * it needs an API which doesn't exist (in this case,
		 * dma_writecombine_mmap)
		 */
		fbi->fb.fix.smem_start = fbi->screen_dma;
	}

	return fbi->map_cpu ? 0 : -ENOMEM;
}

/* Fake monspecs to fill in fbinfo structure */
static struct fb_monspecs monspecs __initdata = {
	.hfmin	= 30000,
	.hfmax	= 70000,
	.vfmin	= 50,
	.vfmax	= 65,
};


static struct sa1100fb_info * __init sa1100fb_init_fbinfo(struct device *dev)
{
	struct sa1100fb_mach_info *inf;
	struct sa1100fb_info *fbi;

	fbi = kmalloc(sizeof(struct sa1100fb_info) + sizeof(u32) * 16,
		      GFP_KERNEL);
	if (!fbi)
		return NULL;

	memset(fbi, 0, sizeof(struct sa1100fb_info));
	fbi->dev = dev;

	strcpy(fbi->fb.fix.id, SA1100_NAME);

	fbi->fb.fix.type	= FB_TYPE_PACKED_PIXELS;
	fbi->fb.fix.type_aux	= 0;
	fbi->fb.fix.xpanstep	= 0;
	fbi->fb.fix.ypanstep	= 0;
	fbi->fb.fix.ywrapstep	= 0;
	fbi->fb.fix.accel	= FB_ACCEL_NONE;

	fbi->fb.var.nonstd	= 0;
	fbi->fb.var.activate	= FB_ACTIVATE_NOW;
	fbi->fb.var.height	= -1;
	fbi->fb.var.width	= -1;
	fbi->fb.var.accel_flags	= 0;
	fbi->fb.var.vmode	= FB_VMODE_NONINTERLACED;

	fbi->fb.fbops		= &sa1100fb_ops;
	fbi->fb.flags		= FBINFO_DEFAULT;
	fbi->fb.monspecs	= monspecs;
	fbi->fb.pseudo_palette	= (fbi + 1);

	fbi->rgb[RGB_8]		= &rgb_8;
	fbi->rgb[RGB_16]	= &def_rgb_16;

	inf = sa1100fb_get_machine_info(fbi);

	/*
	 * People just don't seem to get this.  We don't support
	 * anything but correct entries now, so panic if someone
	 * does something stupid.
	 */
	if (inf->lccr3 & (LCCR3_VrtSnchL|LCCR3_HorSnchL|0xff) ||
	    inf->pixclock == 0)
		panic("sa1100fb error: invalid LCCR3 fields set or zero "
			"pixclock.");

	fbi->max_xres			= inf->xres;
	fbi->fb.var.xres		= inf->xres;
	fbi->fb.var.xres_virtual	= inf->xres;
	fbi->max_yres			= inf->yres;
	fbi->fb.var.yres		= inf->yres;
	fbi->fb.var.yres_virtual	= inf->yres;
	fbi->max_bpp			= inf->bpp;
	fbi->fb.var.bits_per_pixel	= inf->bpp;
	fbi->fb.var.pixclock		= inf->pixclock;
	fbi->fb.var.hsync_len		= inf->hsync_len;
	fbi->fb.var.left_margin		= inf->left_margin;
	fbi->fb.var.right_margin	= inf->right_margin;
	fbi->fb.var.vsync_len		= inf->vsync_len;
	fbi->fb.var.upper_margin	= inf->upper_margin;
	fbi->fb.var.lower_margin	= inf->lower_margin;
	fbi->fb.var.sync		= inf->sync;
	fbi->fb.var.grayscale		= inf->cmap_greyscale;
	fbi->cmap_inverse		= inf->cmap_inverse;
	fbi->cmap_static		= inf->cmap_static;
	fbi->lccr0			= inf->lccr0;
	fbi->lccr3			= inf->lccr3;
	fbi->state			= C_STARTUP;
	fbi->task_state			= (u_char)-1;
	fbi->fb.fix.smem_len		= fbi->max_xres * fbi->max_yres *
					  fbi->max_bpp / 8;

	init_waitqueue_head(&fbi->ctrlr_wait);
	INIT_WORK(&fbi->task, sa1100fb_task);
	mutex_init(&fbi->ctrlr_lock);

	return fbi;
}

static int __init sa1100fb_probe(struct platform_device *pdev)
{
	struct sa1100fb_info *fbi;
	int ret, irq;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
		return -EINVAL;

	if (!request_mem_region(0xb0100000, 0x10000, "LCD"))
		return -EBUSY;

	fbi = sa1100fb_init_fbinfo(&pdev->dev);
	ret = -ENOMEM;
	if (!fbi)
		goto failed;

	/* Initialize video memory */
	ret = sa1100fb_map_video_memory(fbi);
	if (ret)
		goto failed;

	ret = request_irq(irq, sa1100fb_handle_irq, IRQF_DISABLED,
			  "LCD", fbi);
	if (ret) {
		printk(KERN_ERR "sa1100fb: request_irq failed: %d\n", ret);
		goto failed;
	}

#ifdef ASSABET_PAL_VIDEO
	if (machine_is_assabet())
		ASSABET_BCR_clear(ASSABET_BCR_LCD_ON);
#endif

	/*
	 * This makes sure that our colour bitfield
	 * descriptors are correctly initialised.
	 */
	sa1100fb_check_var(&fbi->fb.var, &fbi->fb);

	platform_set_drvdata(pdev, fbi);

	ret = register_framebuffer(&fbi->fb);
	if (ret < 0)
		goto err_free_irq;

#ifdef CONFIG_CPU_FREQ
	fbi->freq_transition.notifier_call = sa1100fb_freq_transition;
	fbi->freq_policy.notifier_call = sa1100fb_freq_policy;
	cpufreq_register_notifier(&fbi->freq_transition, CPUFREQ_TRANSITION_NOTIFIER);
	cpufreq_register_notifier(&fbi->freq_policy, CPUFREQ_POLICY_NOTIFIER);
#endif

	/* This driver cannot be unloaded at the moment */
	return 0;

 err_free_irq:
	free_irq(irq, fbi);
 failed:
	platform_set_drvdata(pdev, NULL);
	kfree(fbi);
	release_mem_region(0xb0100000, 0x10000);
	return ret;
}

static struct platform_driver sa1100fb_driver = {
	.probe		= sa1100fb_probe,
	.suspend	= sa1100fb_suspend,
	.resume		= sa1100fb_resume,
	.driver		= {
		.name	= "sa11x0-fb",
	},
};

int __init sa1100fb_init(void)
{
	if (fb_get_options("sa1100fb", NULL))
		return -ENODEV;

	return platform_driver_register(&sa1100fb_driver);
}

int __init sa1100fb_setup(char *options)
{
#if 0
	char *this_opt;

	if (!options || !*options)
		return 0;

	while ((this_opt = strsep(&options, ",")) != NULL) {

		if (!strncmp(this_opt, "bpp:", 4))
			current_par.max_bpp =
			    simple_strtoul(this_opt + 4, NULL, 0);

		if (!strncmp(this_opt, "lccr0:", 6))
			lcd_shadow.lccr0 =
			    simple_strtoul(this_opt + 6, NULL, 0);
		if (!strncmp(this_opt, "lccr1:", 6)) {
			lcd_shadow.lccr1 =
			    simple_strtoul(this_opt + 6, NULL, 0);
			current_par.max_xres =
			    (lcd_shadow.lccr1 & 0x3ff) + 16;
		}
		if (!strncmp(this_opt, "lccr2:", 6)) {
			lcd_shadow.lccr2 =
			    simple_strtoul(this_opt + 6, NULL, 0);
			current_par.max_yres =
			    (lcd_shadow.
			     lccr0 & LCCR0_SDS) ? ((lcd_shadow.
						    lccr2 & 0x3ff) +
						   1) *
			    2 : ((lcd_shadow.lccr2 & 0x3ff) + 1);
		}
		if (!strncmp(this_opt, "lccr3:", 6))
			lcd_shadow.lccr3 =
			    simple_strtoul(this_opt + 6, NULL, 0);
	}
#endif
	return 0;
}

module_init(sa1100fb_init);
MODULE_DESCRIPTION("StrongARM-1100/1110 framebuffer driver");
MODULE_LICENSE("GPL");