On Tue, Jun 15, 2010 at 5:10 AM, Erik Gilling <konkers@xxxxxxxxxxx> wrote: > diff --git a/drivers/video/tegrafb.c b/drivers/video/tegrafb.c > new file mode 100644 > index 0000000..47b2d42 > --- /dev/null > +++ b/drivers/video/tegrafb.c > +/* palette attary used by the fbcon */ > +u32 pseudo_palette[16]; attary > + > +irqreturn_t tegra_fb_irq(int irq, void *ptr) > +{ > + struct fb_info *info = ptr; > + struct tegra_fb_info *tegra_fb = info->par; > + > + u32 reg = tegra_fb_readl(tegra_fb, DC_CMD_INT_STATUS); > + tegra_fb_writel(tegra_fb, reg, DC_CMD_INT_STATUS); > + > + tegra_fb->wait_condition = 1; > + wake_up(&tegra_fb->event_wq); > + return IRQ_HANDLED; > +} > + > +static int tegra_fb_wait_for_event(struct tegra_fb_info *tegra_fb, > + unsigned long timeout, u32 irq_mask) > +{ > + u32 reg; > + > + tegra_fb->wait_condition = 0; > + > + reg = tegra_fb_readl(tegra_fb, DC_CMD_INT_MASK); > + reg |= irq_mask; > + tegra_fb_writel(tegra_fb, reg, DC_CMD_INT_MASK); > + > + /* Clear any pending interrupt */ > + tegra_fb_writel(tegra_fb, irq_mask, DC_CMD_INT_STATUS); > + > + tegra_fb_writel(tegra_fb, irq_mask, DC_CMD_INT_ENABLE); > + > + /* Wait for the irq to fire */ > + wait_event_interruptible_timeout(tegra_fb->event_wq, > + tegra_fb->wait_condition, timeout); > + > + tegra_fb_writel(tegra_fb, 0, DC_CMD_INT_ENABLE); > + > + if (!tegra_fb->wait_condition) { > + pr_warning("%s: wait for vsync timed out\n", __func__); > + return -ETIMEDOUT; > + } > + return 0; > +} Apologies for the incremental review. The wait_condition code above looks odd to me. Typically, we just test the return value of wait_event_interruptible_timeout to see whether it timed out (returns 0 if so). But I guess the above approach works as well. > + if (tegra_fb_wait_for_event(tegra_fb, HZ/10, DC_INT_FRAME_END)) I still didn't follow how tegra_fb_activate is using the -ETIMEDOUT return value from the wait, it seems like it is just ignored. You are also doing stuff like HZ/10 and you might prefer to use msecs_to_jiffies. Thanks, jaya -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html