From 2bb567a38950f0917aecfe1a3e46720d8bbb0020 Mon Sep 17 00:00:00 2001 From: Maurus Cuelenaere Date: Tue, 10 Aug 2010 18:02:44 -0700 Subject: [PATCH] s3c-fb: automatically calculate pixel clock when none is given Add a simple algorithm which calculates the pixel clock based on the video mode parameters. This is only done when no pixel clock is supplied through the platform data. This allows drivers to omit the pixel clock data and thus share the algorithm used for calculating it. Signed-off-by: Maurus Cuelenaere Cc: Pawel Osciak Cc: Marek Szyprowski Cc: Kyungmin Park Cc: InKi Dae Cc: Ben Dooks Cc: Russell King Tested-by: Donghwa Lee Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/video/s3c-fb.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/drivers/video/s3c-fb.c b/drivers/video/s3c-fb.c index 8ea974dd92c5..f9aca9d13d1b 100644 --- a/drivers/video/s3c-fb.c +++ b/drivers/video/s3c-fb.c @@ -1026,6 +1026,28 @@ static struct fb_ops s3c_fb_ops = { .fb_ioctl = s3c_fb_ioctl, }; +/** + * s3c_fb_missing_pixclock() - calculates pixel clock + * @mode: The video mode to change. + * + * Calculate the pixel clock when none has been given through platform data. + */ +static void __devinit s3c_fb_missing_pixclock(struct fb_videomode *mode) +{ + u64 pixclk = 1000000000000ULL; + u32 div; + + div = mode->left_margin + mode->hsync_len + mode->right_margin + + mode->xres; + div *= mode->upper_margin + mode->vsync_len + mode->lower_margin + + mode->yres; + div *= mode->refresh ? : 60; + + do_div(pixclk, div); + + mode->pixclock = pixclk; +} + /** * s3c_fb_alloc_memory() - allocate display memory for framebuffer window * @sfb: The base resources for the hardware. @@ -1364,6 +1386,9 @@ static int __devinit s3c_fb_probe(struct platform_device *pdev) if (!pd->win[win]) continue; + if (!pd->win[win]->win_mode.pixclock) + s3c_fb_missing_pixclock(&pd->win[win]->win_mode); + ret = s3c_fb_probe_win(sfb, win, fbdrv->win[win], &sfb->windows[win]); if (ret < 0) { -- 2.30.2