fbdev: sh_mobile_hdmi: implement locking

The SH-Mobile HDMI driver runs in several contexts: ISR, delayed work-queue,
task context, when called from the sh_mobile_lcdc framebuffer driver. This
creates ample race possibilities. Even though most these races are purely
theoretical, it is better to close them. To trace fb_info validity we install a
notification callback in the HDMI driver, and the only way for it to get to
driver internal data is by using struct sh_mobile_lcdc_chan, therefore it had
to be extracted into a separate common header.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/drivers/video/sh_mobile_lcdcfb.h b/drivers/video/sh_mobile_lcdcfb.h
new file mode 100644
index 0000000..6fcfc0f
--- /dev/null
+++ b/drivers/video/sh_mobile_lcdcfb.h
@@ -0,0 +1,37 @@
+#ifndef SH_MOBILE_LCDCFB_H
+#define SH_MOBILE_LCDCFB_H
+
+#include <linux/completion.h>
+#include <linux/fb.h>
+#include <linux/wait.h>
+
+/* per-channel registers */
+enum { LDDCKPAT1R, LDDCKPAT2R, LDMT1R, LDMT2R, LDMT3R, LDDFR, LDSM1R,
+       LDSM2R, LDSA1R, LDMLSR, LDHCNR, LDHSYNR, LDVLNR, LDVSYNR, LDPMR,
+       LDHAJR,
+       NR_CH_REGS };
+
+#define PALETTE_NR 16
+
+struct sh_mobile_lcdc_priv;
+struct fb_info;
+
+struct sh_mobile_lcdc_chan {
+	struct sh_mobile_lcdc_priv *lcdc;
+	unsigned long *reg_offs;
+	unsigned long ldmt1r_value;
+	unsigned long enabled; /* ME and SE in LDCNT2R */
+	struct sh_mobile_lcdc_chan_cfg cfg;
+	u32 pseudo_palette[PALETTE_NR];
+	unsigned long saved_ch_regs[NR_CH_REGS];
+	struct fb_info *info;
+	dma_addr_t dma_handle;
+	struct fb_deferred_io defio;
+	struct scatterlist *sglist;
+	unsigned long frame_end;
+	unsigned long pan_offset;
+	wait_queue_head_t frame_end_wait;
+	struct completion vsync_completion;
+};
+
+#endif