Add VSYNC interrupt support and an ioctl that allows waiting for it.
Interrupts are turned on only when needed.
Signed-off-by: Pawel Osciak <p.osciak@xxxxxxxxxxx>
Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
---
arch/arm/plat-samsung/include/plat/regs-fb.h | 1 +
drivers/video/s3c-fb.c | 166 +++++++++++++++++++++++++-
2 files changed, 166 insertions(+), 1 deletions(-)
diff --git a/arch/arm/plat-samsung/include/plat/regs-fb.h b/arch/arm/plat-samsung/include/plat/regs-fb.h
index dbb6c0a..564594e 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 de427d9..2e82adf 100644
--- a/drivers/video/s3c-fb.c
+++ b/drivers/video/s3c-fb.c
@@ -21,6 +21,8 @@
#include <linux/clk.h>
#include <linux/fb.h>
#include <linux/io.h>
+#include <linux/uaccess.h>
+#include <linux/interrupt.h>
#include <mach/map.h>
#include <plat/regs-fb-v4.h>
@@ -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))
@@ -156,6 +163,16 @@ struct s3c_fb_win {
};
/**
+ * 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.
* @regs_res: The resource we claimed for the IO registers.
@@ -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);
--
1.7.1.569.g6f426
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