[PATCH v2 3/3] [ARM] s3c-fb: Added wait for VSYNC support.
Pawel Osciak
p.osciak at samsung.com
Thu Sep 3 08:44:51 EDT 2009
Added FBIO_WAITFORVSYNC ioctl that allows sleeping on vsync
waitqueue.
Reviewed-by: Marek Szyprowski <m.szyprowski at samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park at samsung.com>
Signed-off-by: Pawel Osciak <p.osciak at samsung.com>
---
drivers/video/s3c-fb.c | 170 +++++++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 168 insertions(+), 2 deletions(-)
diff --git a/drivers/video/s3c-fb.c b/drivers/video/s3c-fb.c
index 3dd4327..001a1a1 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 <mach/regs-fb.h>
@@ -48,6 +50,13 @@
__raw_writel(v, r); } while(0)
#endif /* FB_S3C_DEBUG_REGWRITE */
+/* Bit in irq_flags used to mark that interrupts are activated in device */
+#define S3C_FB_IRQ_ENABLED_BIT 0
+
+#ifndef FBIO_WAITFORVSYNC
+#define FBIO_WAITFORVSYNC _IOW('F', 0x20, __u32)
+#endif
+
struct s3c_fb;
/**
@@ -59,6 +68,7 @@ struct s3c_fb;
* @pseudo_palette: For use in TRUECOLOUR modes for entries 0..15/
* @index: The window number of this window.
* @palette: The bitfields for changing r/g/b into a hardware palette entry.
+ * @vsync: Vsync handling helper.
*/
struct s3c_fb_win {
struct s3c_fb_pd_win *windata;
@@ -72,6 +82,16 @@ struct s3c_fb_win {
};
/**
+ * struct s3c_fb_vsync - vsync information for display.
+ * @vsync_queue: A queue for processes waiting for vsync.
+ * @vsync_count: Vsync interrupt count.
+ */
+struct s3c_fb_vsync {
+ wait_queue_head_t vsync_queue;
+ unsigned long vsync_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.
@@ -80,6 +100,8 @@ 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 number for the device (acquired from platform data).
+ * @vsync_info: VSYNC-related information (count, queues...)
*/
struct s3c_fb {
struct device *dev;
@@ -87,10 +109,15 @@ struct s3c_fb {
struct clk *bus_clk;
void __iomem *regs;
- unsigned char enabled;
+ unsigned char enabled;
struct s3c_fb_platdata *pdata;
struct s3c_fb_win *windows[S3C_FB_MAX_WIN];
+
+ unsigned int irq_no;
+ unsigned long irq_flags;
+
+ struct s3c_fb_vsync vsync_info;
};
/**
@@ -643,6 +670,103 @@ static int s3c_fb_blank(int blank_mode, struct fb_info *info)
}
/**
+ * s3c_fb_enable_irq() - enable interrupts in hardware.
+ * @sfb: The base resources for the hardware.
+ */
+static int s3c_fb_enable_irq(struct s3c_fb *sfb)
+{
+ u32 irq_ctrl_reg;
+ void __iomem *regs = sfb->regs;
+
+ if (!test_and_set_bit(S3C_FB_IRQ_ENABLED_BIT, &sfb->irq_flags)) {
+ /* IRQ was 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);
+ }
+
+ return 0;
+}
+
+/**
+ * s3c_fb_disable_irq() - disable interrupts in hardware.
+ * @sfb: The base resources for the hardware.
+ */
+static int s3c_fb_disable_irq(struct s3c_fb *sfb)
+{
+ u32 irq_ctrl_reg;
+ void __iomem *regs = sfb->regs;
+
+ if (test_and_clear_bit(S3C_FB_IRQ_ENABLED_BIT, &sfb->irq_flags)) {
+ /* IRQ was 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);
+ }
+
+ return 0;
+}
+
+static irqreturn_t s3c_fb_interrupt(int irq, void *dev_id)
+{
+ u32 irq_sts_reg;
+ struct s3c_fb *sfb = dev_id;
+ void __iomem *regs = sfb->regs;
+
+ 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.vsync_count++;
+ wake_up_interruptible(&sfb->vsync_info.vsync_queue);
+ }
+
+ /* We support only waiting for VSYNC interrupt for now,
+ * so it's safe to disable irqs here. */
+ s3c_fb_disable_irq(sfb);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * s3c_fb_wait_for_vsync() - sleep until next VSYNC interrupt or timeout.
+ * @sfb: The base resources for the hardware.
+ * @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;
+
+ s3c_fb_enable_irq(sfb);
+ count = sfb->vsync_info.vsync_count;
+ ret = wait_event_interruptible_timeout(sfb->vsync_info.vsync_queue,
+ count != sfb->vsync_info.vsync_count,
+ HZ / 10);
+ if (ret == 0)
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+/**
* s3c_fb_pan_display() - Pan the display.
*
* Note, that the offsets can be written to the device at any time, as their
@@ -697,6 +821,27 @@ static int s3c_fb_pan_display(struct fb_var_screeninfo *var,
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;
+
+ switch (cmd) {
+ case FBIO_WAITFORVSYNC: {
+ u32 crtc;
+ if (get_user(crtc, (u32 __user *)arg))
+ return -EFAULT;
+
+ return s3c_fb_wait_for_vsync(sfb, crtc);
+ }
+ default:
+ return -ENOTTY;
+ }
+
+ return 0;
+}
+
static struct fb_ops s3c_fb_ops = {
.owner = THIS_MODULE,
.fb_check_var = s3c_fb_check_var,
@@ -706,6 +851,7 @@ static struct fb_ops s3c_fb_ops = {
.fb_fillrect = cfb_fillrect,
.fb_copyarea = cfb_copyarea,
.fb_imageblit = cfb_imageblit,
+ .fb_ioctl = s3c_fb_ioctl,
.fb_pan_display = s3c_fb_pan_display,
};
@@ -931,6 +1077,7 @@ static int __devinit s3c_fb_probe(struct platform_device *pdev)
sfb->dev = dev;
sfb->pdata = pd;
+ init_waitqueue_head(&sfb->vsync_info.vsync_queue);
sfb->bus_clk = clk_get(dev, "lcd");
if (IS_ERR(sfb->bus_clk)) {
@@ -962,6 +1109,20 @@ 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_interrupt,
+ 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 */
@@ -986,7 +1147,7 @@ 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;
}
}
@@ -994,6 +1155,9 @@ 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);
@@ -1026,6 +1190,8 @@ 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);
--
1.6.4.2.253.g0b1fac
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