atmel_lcdfb: add board parameter specify framebuffer memory size

Specify how much physically continuous, DMA capable memory will be
allocated at driver initialization time.  This allow to create framebuffer
device with larger virtual resolution.  Combine with y-panning this can be
used to implement double buffering acceleration method.

Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index 16e47eb..9c59259 100644 (file)
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -242,9 +242,11 @@ static int atmel_lcdfb_alloc_video_memory(struct atmel_lcdfb_info *sinfo)
 {
        struct fb_info *info = sinfo->info;
        struct fb_var_screeninfo *var = &info->var;
+       unsigned int smem_len;
 
-       info->fix.smem_len = (var->xres_virtual * var->yres_virtual
-                           * ((var->bits_per_pixel + 7) / 8));
+       smem_len = (var->xres_virtual * var->yres_virtual
+                   * ((var->bits_per_pixel + 7) / 8));
+       info->fix.smem_len = max(smem_len, sinfo->smem_len);
 
        info->screen_base = dma_alloc_writecombine(info->device, info->fix.smem_len,
                                        (dma_addr_t *)&info->fix.smem_start, GFP_KERNEL);
@@ -796,6 +798,7 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
                sinfo->default_monspecs = pdata_sinfo->default_monspecs;
                sinfo->atmel_lcdfb_power_control = pdata_sinfo->atmel_lcdfb_power_control;
                sinfo->guard_time = pdata_sinfo->guard_time;
+               sinfo->smem_len = pdata_sinfo->smem_len;
                sinfo->lcdcon_is_backlight = pdata_sinfo->lcdcon_is_backlight;
                sinfo->lcd_wiring_mode = pdata_sinfo->lcd_wiring_mode;
        } else {

diff --git a/include/video/atmel_lcdc.h b/include/video/atmel_lcdc.h
index 613173b..920c4e9 100644 (file)
--- a/include/video/atmel_lcdc.h
+++ b/include/video/atmel_lcdc.h
@@ -41,6 +41,7 @@ struct atmel_lcdfb_info {
        struct work_struct      task;
 
        unsigned int            guard_time;
+       unsigned int            smem_len;
        struct platform_device  *pdev;
        struct clk              *bus_clk;
        struct clk              *lcdc_clk;