fbdev: sh_mobile_hdmi: add support for E-EDID parsing

Many HDMI clients implement enhanced EDID blocks, which often contain
additional supported video modes. This patch implements parsing of such
E-EDID blocks.

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_hdmi.c b/drivers/video/sh_mobile_hdmi.c
index 3b4cf987fb4377dbf33a6e89a23a62e6a71d9e82..76f9fac9020ff7967b424e998ef0c16cdb71a658 100644 (file)
--- a/drivers/video/sh_mobile_hdmi.c
+++ b/drivers/video/sh_mobile_hdmi.c
@@ -211,6 +211,9 @@ struct sh_hdmi {
        enum hotplug_state hp_state;    /* hot-plug status */
        u8 preprogrammed_vic;           /* use a pre-programmed VIC or
                                           the external mode */
+       u8 edid_block_addr;
+       u8 edid_segment_nr;
+       u8 edid_blocks;
        struct clk *hdmi_clk;
        struct device *dev;
        struct fb_info *info;
@@ -756,7 +759,38 @@ static int sh_hdmi_read_edid(struct sh_hdmi *hdmi, unsigned long *hdmi_rate,
        printk(KERN_CONT "\n");
 #endif
 
-       fb_edid_to_monspecs(edid, &hdmi->monspec);
+       if (!hdmi->edid_blocks) {
+               fb_edid_to_monspecs(edid, &hdmi->monspec);
+               hdmi->edid_blocks = edid[126] + 1;
+
+               dev_dbg(hdmi->dev, "%d main modes, %d extension blocks\n",
+                       hdmi->monspec.modedb_len, hdmi->edid_blocks - 1);
+       } else {
+               dev_dbg(hdmi->dev, "Extension %u detected, DTD start %u\n",
+                       edid[0], edid[2]);
+               fb_edid_add_monspecs(edid, &hdmi->monspec);
+       }
+
+       if (hdmi->edid_blocks > hdmi->edid_segment_nr * 2 +
+           (hdmi->edid_block_addr >> 7) + 1) {
+               /* More blocks to read */
+               if (hdmi->edid_block_addr) {
+                       hdmi->edid_block_addr = 0;
+                       hdmi->edid_segment_nr++;
+               } else {
+                       hdmi->edid_block_addr = 0x80;
+               }
+               /* Set EDID word address  */
+               hdmi_write(hdmi, hdmi->edid_block_addr, HDMI_EDID_WORD_ADDRESS);
+               /* Enable EDID interrupt */
+               hdmi_write(hdmi, 0xC6, HDMI_INTERRUPT_MASK_1);
+               /* Set EDID segment pointer - starts reading EDID */
+               hdmi_write(hdmi, hdmi->edid_segment_nr, HDMI_EDID_SEGMENT_POINTER);
+               return -EAGAIN;
+       }
+
+       /* All E-EDID blocks ready */
+       dev_dbg(hdmi->dev, "%d main and extended modes\n", hdmi->monspec.modedb_len);
 
        fb_get_options("sh_mobile_lcdc", &forced);
        if (forced && *forced) {
@@ -903,32 +937,34 @@ static irqreturn_t sh_hdmi_hotplug(int irq, void *dev_id)
                /* Check, if hot plug & MSENS pin status are both high */
                if ((msens & 0xC0) == 0xC0) {
                        /* Display plug in */
+                       hdmi->edid_segment_nr = 0;
+                       hdmi->edid_block_addr = 0;
+                       hdmi->edid_blocks = 0;
                        hdmi->hp_state = HDMI_HOTPLUG_CONNECTED;
 
                        /* Set EDID word address  */
                        hdmi_write(hdmi, 0x00, HDMI_EDID_WORD_ADDRESS);
-                       /* Set EDID segment pointer */
-                       hdmi_write(hdmi, 0x00, HDMI_EDID_SEGMENT_POINTER);
                        /* Enable EDID interrupt */
                        hdmi_write(hdmi, 0xC6, HDMI_INTERRUPT_MASK_1);
+                       /* Set EDID segment pointer - starts reading EDID */
+                       hdmi_write(hdmi, 0x00, HDMI_EDID_SEGMENT_POINTER);
                } else if (!(status1 & 0x80)) {
                        /* Display unplug, beware multiple interrupts */
-                       if (hdmi->hp_state != HDMI_HOTPLUG_DISCONNECTED)
+                       if (hdmi->hp_state != HDMI_HOTPLUG_DISCONNECTED) {
+                               hdmi->hp_state = HDMI_HOTPLUG_DISCONNECTED;
                                schedule_delayed_work(&hdmi->edid_work, 0);
-
-                       hdmi->hp_state = HDMI_HOTPLUG_DISCONNECTED;
+                       }
                        /* display_off will switch back to mode_a */
                }
        } else if (status1 & 2) {
                /* EDID error interrupt: retry */
                /* Set EDID word address  */
-               hdmi_write(hdmi, 0x00, HDMI_EDID_WORD_ADDRESS);
+               hdmi_write(hdmi, hdmi->edid_block_addr, HDMI_EDID_WORD_ADDRESS);
                /* Set EDID segment pointer */
-               hdmi_write(hdmi, 0x00, HDMI_EDID_SEGMENT_POINTER);
+               hdmi_write(hdmi, hdmi->edid_segment_nr, HDMI_EDID_SEGMENT_POINTER);
        } else if (status1 & 4) {
                /* Disable EDID interrupt */
                hdmi_write(hdmi, 0xC0, HDMI_INTERRUPT_MASK_1);
-               hdmi->hp_state = HDMI_HOTPLUG_EDID_DONE;
                schedule_delayed_work(&hdmi->edid_work, msecs_to_jiffies(10));
        }
 
@@ -1056,7 +1092,7 @@ static void sh_hdmi_edid_work_fn(struct work_struct *work)
 
        mutex_lock(&hdmi->mutex);
 
-       if (hdmi->hp_state == HDMI_HOTPLUG_EDID_DONE) {
+       if (hdmi->hp_state == HDMI_HOTPLUG_CONNECTED) {
                unsigned long parent_rate = 0, hdmi_rate;
 
                /* A device has been plugged in */
@@ -1066,6 +1102,8 @@ static void sh_hdmi_edid_work_fn(struct work_struct *work)
                if (ret < 0)
                        goto out;
 
+               hdmi->hp_state = HDMI_HOTPLUG_EDID_DONE;
+
                /* Reconfigure the clock */
                ret = sh_hdmi_clk_configure(hdmi, hdmi_rate, parent_rate);
                if (ret < 0)
@@ -1119,7 +1157,7 @@ static void sh_hdmi_edid_work_fn(struct work_struct *work)
        }
 
 out:
-       if (ret < 0)
+       if (ret < 0 && ret != -EAGAIN)
                hdmi->hp_state = HDMI_HOTPLUG_DISCONNECTED;
        mutex_unlock(&hdmi->mutex);