From efdc846d2f7190c8f3092c09975c0ebba30a95ba Mon Sep 17 00:00:00 2001 From: Pawel Osciak Date: Tue, 10 Aug 2010 18:02:38 -0700 Subject: [PATCH] s3c-fb: add wait for VSYNC ioctl Add VSYNC interrupt support and an ioctl that allows waiting for it. Interrupts are turned on only when needed. Signed-off-by: Pawel Osciak Signed-off-by: Kyungmin Park Cc: InKi Dae Cc: Ben Dooks Cc: Marek Szyprowski Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm/plat-samsung/include/plat/regs-fb.h | 1 + drivers/video/s3c-fb.c | 166 ++++++++++++++++++- 2 files changed, 166 insertions(+), 1 deletion(-) diff --git a/arch/arm/plat-samsung/include/plat/regs-fb.h b/arch/arm/plat-samsung/include/plat/regs-fb.h index dbb6c0afef47..564594e89efe 100644 --- a/arch/arm/plat-samsung/include/plat/regs-fb.h +++ b/arch/arm/plat-samsung/include/plat/regs-fb.h @@ -300,6 +300,7 @@ #define VIDINTCON0_FRAMESEL0_FRONTPORCH (0x3 << 15) #define VIDINTCON0_FRAMESEL1 (1 << 13) +#define VIDINTCON0_FRAMESEL1_MASK (0x3 << 13) #define VIDINTCON0_FRAMESEL1_NONE (0x0 << 13) #define VIDINTCON0_FRAMESEL1_BACKPORCH (0x1 << 13) #define VIDINTCON0_FRAMESEL1_VSYNC (0x2 << 13) diff --git a/drivers/video/s3c-fb.c b/drivers/video/s3c-fb.c index de427d928f48..2e82adf9ab6d 100644 --- a/drivers/video/s3c-fb.c +++ b/drivers/video/s3c-fb.c @@ -21,6 +21,8 @@ #include #include #include +#include +#include #include #include @@ -48,6 +50,11 @@ __raw_writel(v, r); } while(0) #endif /* FB_S3C_DEBUG_REGWRITE */ +/* irq_flags bits */ +#define S3C_FB_VSYNC_IRQ_EN 0 + +#define VSYNC_TIMEOUT_MSEC 50 + struct s3c_fb; #define VALID_BPP(x) (1 << ((x) - 1)) @@ -155,6 +162,16 @@ struct s3c_fb_win { unsigned int index; }; +/** + * struct s3c_fb_vsync - vsync information + * @wait: a queue for processes waiting for vsync + * @count: vsync interrupt count + */ +struct s3c_fb_vsync { + wait_queue_head_t wait; + unsigned int count; +}; + /** * struct s3c_fb - overall hardware state of the hardware * @dev: The device that we bound to, for printing, etc. @@ -165,6 +182,9 @@ struct s3c_fb_win { * @enabled: A bitmask of enabled hardware windows. * @pdata: The platform configuration data passed with the device. * @windows: The hardware windows that have been claimed. + * @irq_no: IRQ line number + * @irq_flags: irq flags + * @vsync_info: VSYNC-related information (count, queues...) */ struct s3c_fb { struct device *dev; @@ -177,6 +197,10 @@ struct s3c_fb { struct s3c_fb_platdata *pdata; struct s3c_fb_win *windows[S3C_FB_MAX_WIN]; + + int irq_no; + unsigned long irq_flags; + struct s3c_fb_vsync vsync_info; }; /** @@ -798,6 +822,124 @@ static int s3c_fb_pan_display(struct fb_var_screeninfo *var, return 0; } +/** + * s3c_fb_enable_irq() - enable framebuffer interrupts + * @sfb: main hardware state + */ +static void s3c_fb_enable_irq(struct s3c_fb *sfb) +{ + void __iomem *regs = sfb->regs; + u32 irq_ctrl_reg; + + if (!test_and_set_bit(S3C_FB_VSYNC_IRQ_EN, &sfb->irq_flags)) { + /* IRQ disabled, enable it */ + irq_ctrl_reg = readl(regs + VIDINTCON0); + + irq_ctrl_reg |= VIDINTCON0_INT_ENABLE; + irq_ctrl_reg |= VIDINTCON0_INT_FRAME; + + irq_ctrl_reg &= ~VIDINTCON0_FRAMESEL0_MASK; + irq_ctrl_reg |= VIDINTCON0_FRAMESEL0_VSYNC; + irq_ctrl_reg &= ~VIDINTCON0_FRAMESEL1_MASK; + irq_ctrl_reg |= VIDINTCON0_FRAMESEL1_NONE; + + writel(irq_ctrl_reg, regs + VIDINTCON0); + } +} + +/** + * s3c_fb_disable_irq() - disable framebuffer interrupts + * @sfb: main hardware state + */ +static void s3c_fb_disable_irq(struct s3c_fb *sfb) +{ + void __iomem *regs = sfb->regs; + u32 irq_ctrl_reg; + + if (test_and_clear_bit(S3C_FB_VSYNC_IRQ_EN, &sfb->irq_flags)) { + /* IRQ enabled, disable it */ + irq_ctrl_reg = readl(regs + VIDINTCON0); + + irq_ctrl_reg &= ~VIDINTCON0_INT_FRAME; + irq_ctrl_reg &= ~VIDINTCON0_INT_ENABLE; + + writel(irq_ctrl_reg, regs + VIDINTCON0); + } +} + +static irqreturn_t s3c_fb_irq(int irq, void *dev_id) +{ + struct s3c_fb *sfb = dev_id; + void __iomem *regs = sfb->regs; + u32 irq_sts_reg; + + irq_sts_reg = readl(regs + VIDINTCON1); + + if (irq_sts_reg & VIDINTCON1_INT_FRAME) { + + /* VSYNC interrupt, accept it */ + writel(VIDINTCON1_INT_FRAME, regs + VIDINTCON1); + + sfb->vsync_info.count++; + wake_up_interruptible(&sfb->vsync_info.wait); + } + + /* We only support waiting for VSYNC for now, so it's safe + * to always disable irqs here. + */ + s3c_fb_disable_irq(sfb); + + return IRQ_HANDLED; +} + +/** + * s3c_fb_wait_for_vsync() - sleep until next VSYNC interrupt or timeout + * @sfb: main hardware state + * @crtc: head index. + */ +static int s3c_fb_wait_for_vsync(struct s3c_fb *sfb, u32 crtc) +{ + unsigned long count; + int ret; + + if (crtc != 0) + return -ENODEV; + + count = sfb->vsync_info.count; + s3c_fb_enable_irq(sfb); + ret = wait_event_interruptible_timeout(sfb->vsync_info.wait, + count != sfb->vsync_info.count, + msecs_to_jiffies(VSYNC_TIMEOUT_MSEC)); + if (ret == 0) + return -ETIMEDOUT; + + return 0; +} + +static int s3c_fb_ioctl(struct fb_info *info, unsigned int cmd, + unsigned long arg) +{ + struct s3c_fb_win *win = info->par; + struct s3c_fb *sfb = win->parent; + int ret; + u32 crtc; + + switch (cmd) { + case FBIO_WAITFORVSYNC: + if (get_user(crtc, (u32 __user *)arg)) { + ret = -EFAULT; + break; + } + + ret = s3c_fb_wait_for_vsync(sfb, crtc); + break; + default: + ret = -ENOTTY; + } + + return ret; +} + static struct fb_ops s3c_fb_ops = { .owner = THIS_MODULE, .fb_check_var = s3c_fb_check_var, @@ -808,6 +950,7 @@ static struct fb_ops s3c_fb_ops = { .fb_copyarea = cfb_copyarea, .fb_imageblit = cfb_imageblit, .fb_pan_display = s3c_fb_pan_display, + .fb_ioctl = s3c_fb_ioctl, }; /** @@ -914,6 +1057,8 @@ static int __devinit s3c_fb_probe_win(struct s3c_fb *sfb, unsigned int win_no, dev_dbg(sfb->dev, "probing window %d, variant %p\n", win_no, variant); + init_waitqueue_head(&sfb->vsync_info.wait); + palette_size = variant->palette_sz * 4; fbinfo = framebuffer_alloc(sizeof(struct s3c_fb_win) + @@ -1093,6 +1238,20 @@ static int __devinit s3c_fb_probe(struct platform_device *pdev) goto err_req_region; } + res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!res) { + dev_err(dev, "failed to acquire irq resource\n"); + ret = -ENOENT; + goto err_ioremap; + } + sfb->irq_no = res->start; + ret = request_irq(sfb->irq_no, s3c_fb_irq, + 0, "s3c_fb", sfb); + if (ret) { + dev_err(dev, "irq request failed\n"); + goto err_ioremap; + } + dev_dbg(dev, "got resources (regs %p), probing windows\n", sfb->regs); /* setup gpio and output polarity controls */ @@ -1127,7 +1286,7 @@ static int __devinit s3c_fb_probe(struct platform_device *pdev) dev_err(dev, "failed to create window %d\n", win); for (; win >= 0; win--) s3c_fb_release_win(sfb, sfb->windows[win]); - goto err_ioremap; + goto err_irq; } } @@ -1135,6 +1294,9 @@ static int __devinit s3c_fb_probe(struct platform_device *pdev) return 0; +err_irq: + free_irq(sfb->irq_no, sfb); + err_ioremap: iounmap(sfb->regs); @@ -1167,6 +1329,8 @@ static int __devexit s3c_fb_remove(struct platform_device *pdev) if (sfb->windows[win]) s3c_fb_release_win(sfb, sfb->windows[win]); + free_irq(sfb->irq_no, sfb); + iounmap(sfb->regs); clk_disable(sfb->bus_clk); -- 2.20.1