1 files changed, 99 insertions, 0 deletions
diff --git a/drivers/video/omap2/displays/panel-generic-dpi.c b/drivers/video/omap2/displays/panel-generic-dpi.c
index 687c9c7d219..851833669fe 100644
--- a/drivers/video/omap2/displays/panel-generic-dpi.c
+++ b/drivers/video/omap2/displays/panel-generic-dpi.c
@@ -33,6 +33,8 @@
 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
+#include <linux/i2c.h>
+#include "../../edid.h"
 
 #include <plat/panel-generic-dpi.h>
 
@@ -380,6 +382,100 @@ static int generic_dpi_panel_check_timings(struct omap_dss_device *dssdev,
 	return dpi_check_timings(dssdev, timings);
 }
 
+/* i2c / edid support */
+
+#define DDC_ADDR 0x50
+
+static int do_probe_ddc_edid(struct i2c_adapter *adapter,
+		unsigned char *buf, int block, int len)
+{
+	unsigned char start = block * EDID_LENGTH;
+	int i;
+	struct i2c_msg msgs[] = {
+		{
+			.addr   = DDC_ADDR,
+			.flags  = 0,
+			.len    = 1,
+			.buf    = &start,
+		}, {
+			.addr   = DDC_ADDR,
+			.flags  = I2C_M_RD,
+			.len    = len,
+			.buf    = buf,
+		}
+	};
+
+	/* try at least 3 times, avoid miss for time-out */
+	for (i = 0; i < 3; i++) {
+		if (i2c_transfer(adapter, msgs, 2) == 2)
+			return 0;
+	}
+
+	return -1;
+}
+
+static int generic_dpi_panel_get_edid(struct omap_dss_device *dssdev,
+		u8 *buf, int len)
+{
+	struct panel_generic_dpi_data *panel_data = get_panel_data(dssdev);
+	struct i2c_adapter *adapter;
+	int i;
+	u8 *edid, *new;
+
+	adapter = i2c_get_adapter(panel_data->i2c_bus_num);
+	if (!adapter) {
+		printk(KERN_ERR "Invalid I2C adapter, bus number: %d\n",
+				panel_data->i2c_bus_num);
+		return -EINVAL;
+	}
+
+	if ((edid = kmalloc(EDID_LENGTH, GFP_KERNEL)) == NULL)
+		return -EINVAL;
+
+	if (do_probe_ddc_edid(adapter, edid, 0, EDID_LENGTH))
+		goto out;
+
+	/* if there are extensions, probe more */
+	if (edid[0x7e] != 0) {
+		new = krealloc(edid, (edid[0x7e] + 1) * EDID_LENGTH,
+					GFP_KERNEL);
+		if (!new)
+			goto out;
+		edid = new;
+
+		for (i = 1; i <= edid[0x7e]; i++) {
+			if (do_probe_ddc_edid(adapter,
+					edid + i * EDID_LENGTH,
+					i, EDID_LENGTH))
+				goto out;
+		}
+	}
+
+	if (edid) {
+		memcpy(buf, edid, len);
+		kfree(edid);
+		return 0;
+	}
+
+out:
+	kfree(edid);
+	return -EINVAL;
+}
+
+static bool generic_dpi_panel_is_detected(struct omap_dss_device *dssdev)
+{
+	struct panel_generic_dpi_data *panel_data = get_panel_data(dssdev);
+	struct i2c_adapter *adapter;
+	unsigned char out;
+
+	adapter = i2c_get_adapter(panel_data->i2c_bus_num);
+	if (!adapter) {
+		return omapdss_default_is_detected(dssdev);
+	}
+
+	return (do_probe_ddc_edid(adapter, &out, 0, 1) == 0);
+}
+
 static struct omap_dss_driver dpi_driver = {
 	.probe		= generic_dpi_panel_probe,
 	.remove		= generic_dpi_panel_remove,
@@ -393,6 +489,9 @@ static struct omap_dss_driver dpi_driver = {
 	.get_timings	= generic_dpi_panel_get_timings,
 	.check_timings	= generic_dpi_panel_check_timings,
 
+	.get_edid	= generic_dpi_panel_get_edid,
+	.is_detected	= generic_dpi_panel_is_detected,
+
 	.driver         = {
 		.name   = "generic_dpi_panel",
 		.owner  = THIS_MODULE,