Video/Framebuffer: add fuctional power management support to Blackfin BF54x LQ043 framebuffer driver

Fix bug: does nor properply resume after suspend mem
Fix for PM_SUSPEND_MEM: Save and restore peripheral base and DMA registers

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/bf54x-lq043fb.c

@@ -733,7 +733,6 @@ static int bfin_bf54x_remove(struct platform_device *pdev)
 static int bfin_bf54x_suspend(struct platform_device *pdev, pm_message_t state)
 {
 	struct fb_info *fbinfo = platform_get_drvdata(pdev);
-	struct bfin_bf54xfb_info *info = fbinfo->par;
 
 	bfin_write_EPPI0_CONTROL(bfin_read_EPPI0_CONTROL() & ~EPPI_EN);
 	disable_dma(CH_EPPI0);
@@ -747,8 +746,18 @@ static int bfin_bf54x_resume(struct platform_device *pdev)
 	struct fb_info *fbinfo = platform_get_drvdata(pdev);
 	struct bfin_bf54xfb_info *info = fbinfo->par;
 
-	enable_dma(CH_EPPI0);
-	bfin_write_EPPI0_CONTROL(bfin_read_EPPI0_CONTROL() | EPPI_EN);
+	if (info->lq043_open_cnt) {
+
+		bfin_write_EPPI0_CONTROL(0);
+		SSYNC();
+
+		config_dma(info);
+		config_ppi(info);
+
+		/* start dma */
+		enable_dma(CH_EPPI0);
+		bfin_write_EPPI0_CONTROL(bfin_read_EPPI0_CONTROL() | EPPI_EN);
+	}
 
 	return 0;
 }