HDMI: Add edid read and clear functions

Add edid read and clear function for panel driver to use.

Change-Id: I64e91266ed20de4bfbfdfe4bbd1e426a414e1503
Signed-off-by: Dandawate Saket <dsaket@ti.com>

2 files changed, 63 insertions, 1 deletions

diff --git a/drivers/video/omap2/dss/dss.h b/drivers/video/omap2/dss/dss.h
index 3c3df510eae..981fcf86d72 100755
--- a/drivers/video/omap2/dss/dss.h
+++ b/drivers/video/omap2/dss/dss.h
@@ -502,6 +502,9 @@ void sel_i2c(void);
 void sel_hdmi(void);
 int omapdss_hdmi_display_set_mode(struct omap_dss_device *dssdev,
                                         struct fb_videomode *mode);
+u8 *hdmi_read_valid_edid(void);
+void omapdss_hdmi_clear_edid(void);
+ssize_t omapdss_get_edid(char *buf);
 int hdmi_panel_init(void);
 void hdmi_panel_exit(void);
 #if defined(CONFIG_OMAP4_DSS_HDMI_AUDIO) || \
diff --git a/drivers/video/omap2/dss/hdmi.c b/drivers/video/omap2/dss/hdmi.c
index da50133b621..43f55938a58 100755
--- a/drivers/video/omap2/dss/hdmi.c
+++ b/drivers/video/omap2/dss/hdmi.c
@@ -48,10 +48,11 @@
 #include "dss_features.h"
 
 /* HDMI EDID Length move this */
-#define HDMI_EDID_MAX_LENGTH                    256
+#define HDMI_EDID_MAX_LENGTH                    512
 #define EDID_TIMING_DESCRIPTOR_SIZE             0x12
 #define EDID_DESCRIPTOR_BLOCK0_ADDRESS          0x36
 #define EDID_DESCRIPTOR_BLOCK1_ADDRESS          0x80
+#define EDID_HDMI_VENDOR_SPECIFIC_DATA_BLOCK    128
 #define EDID_SIZE_BLOCK0_TIMING_DESCRIPTOR      4
 #define EDID_SIZE_BLOCK1_TIMING_DESCRIPTOR      4
 
@@ -64,6 +65,8 @@ static struct {
 #endif
         int code;
         int mode;
+        u8 edid[HDMI_EDID_MAX_LENGTH];
+        bool edid_set;
         bool custom_set;
 
         struct hdmi_ip_data ip_data;
@@ -94,6 +97,8 @@ static struct {
         struct omap_dss_output output;
 } hdmi;
 
+static const u8 edid_header[8] = {0x0, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x0};
+
 /*
  * Logic for the below structure :
  * user enters the CEA or VESA timings by specifying the HDMI/DVI code.
@@ -616,6 +621,45 @@ end:	return cm;
 
 }
 
+u8 *hdmi_read_valid_edid(void)
+{
+        int ret, i;
+
+        if (hdmi.edid_set)
+                return hdmi.edid;
+
+        memset(hdmi.edid, 0, HDMI_EDID_MAX_LENGTH);
+
+        hdmi_runtime_get();
+
+        ret = hdmi.ip_data.ops->read_edid(&hdmi.ip_data, hdmi.edid,
+                                                  HDMI_EDID_MAX_LENGTH);
+
+        hdmi_runtime_put();
+
+        for (i = 0; i < HDMI_EDID_MAX_LENGTH; i += 16)
+                DSSDBG("edid[%03x] = %02x %02x %02x %02x %02x %02x %02x %02x "\
+                        "%02x %02x %02x %02x %02x %02x %02x %02x\n", i,
+                        hdmi.edid[i], hdmi.edid[i + 1], hdmi.edid[i + 2],
+                        hdmi.edid[i + 3], hdmi.edid[i + 4], hdmi.edid[i + 5],
+                        hdmi.edid[i + 6], hdmi.edid[i + 7], hdmi.edid[i + 8],
+                        hdmi.edid[i + 9], hdmi.edid[i + 10], hdmi.edid[i + 11],
+                        hdmi.edid[i + 12], hdmi.edid[i + 13], hdmi.edid[i + 14],
+                        hdmi.edid[i + 15]);
+
+        if (ret) {
+                DSSWARN("failed to read E-EDID\n");
+                return NULL;
+        }
+        if (memcmp(hdmi.edid, edid_header, sizeof(edid_header))) {
+                DSSWARN("failed to read E-EDID: wrong header\n");
+                return NULL;
+        }
+        hdmi.edid_set = true;
+
+        return hdmi.edid;
+}
+
 unsigned long hdmi_get_pixel_clock(void)
 {
         /* HDMI Pixel Clock in Mhz */
@@ -1271,6 +1315,19 @@ void omapdss_hdmi_core_disable(struct omap_dss_device *dssdev)
         mutex_unlock(&hdmi.lock);
 }
 
+void omapdss_hdmi_clear_edid(void)
+{
+        hdmi.edid_set = false;
+        hdmi.custom_set = false;
+}
+
+ssize_t omapdss_get_edid(char *buf)
+{
+        ssize_t size = hdmi.edid_set ? HDMI_EDID_MAX_LENGTH : 0;
+        memcpy(buf, hdmi.edid, size);
+        return size;
+}
+
 static irqreturn_t hdmi_irq_handler(int irq, void *arg)
 {
         int r = 0;
@@ -1968,6 +2025,8 @@ static int __init omapdss_hdmihw_probe(struct platform_device *pdev)
                 goto err_panel_init;
         }
 
+        hdmi.edid_set = false;
+
         dss_debugfs_create_file("hdmi", hdmi_dump_regs);
 
         hdmi_init_output(pdev);