video: tegra: flesh out edid support

* read blocks in a single command instead of byte at a time
* allow reading past segment 0 (edid > 256 bytes)
* handle mutiple extention blocks
* add debugfs file for reading edid

Change-Id: Iec8182cdbccdaa2142e4bbc892202d2e8d73c23b
Signed-off-by: Erik Gilling <konkers@android.com>

diff --git a/drivers/video/tegra/dc/edid.c b/drivers/video/tegra/dc/edid.c
index 0b0b1a760a4e04b673f85a3c5cee2a30fbdbdd73..812a0087a96d4940b2dfed4d38e2d085c03ffb44 100644 (file)
--- a/drivers/video/tegra/dc/edid.c
+++ b/drivers/video/tegra/dc/edid.c
@@ -15,31 +15,181 @@
  *
  */
 
-#include <linux/i2c.h>
+#define DEBUG
+
+#include <linux/debugfs.h>
 #include <linux/fb.h>
+#include <linux/i2c.h>
+#include <linux/seq_file.h>
+#include <linux/vmalloc.h>
 
 #include "edid.h"
 
+struct tegra_edid {
+       struct i2c_client       *client;
+       struct i2c_board_info   info;
+       int                     bus;
+
+       u8                      *data;
+       unsigned                len;
+};
+
+#if defined(DEBUG) || defined(CONFIG_DEBUG_FS)
+static int tegra_edid_show(struct seq_file *s, void *unused)
+{
+       struct tegra_edid *edid = s->private;
+       int i;
+
+       for (i = 0; i < edid->len; i++) {
+               if (i % 16 == 0)
+                       seq_printf(s, "edid[%03x] =", i);
+
+               seq_printf(s, " %02x", edid->data[i]);
+
+               if (i % 16 == 15)
+                       seq_printf(s, "\n");
+       }
+
+       return 0;
+}
+#endif
+
+#ifdef CONFIG_DEBUG_FS
+static int tegra_edid_debug_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, tegra_edid_show, inode->i_private);
+}
+
+static const struct file_operations tegra_edid_debug_fops = {
+       .open           = tegra_edid_debug_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
+void tegra_edid_debug_add(struct tegra_edid *edid)
+{
+       char name[] = "edidX";
+
+       snprintf(name, sizeof(name), "edid%1d", edid->bus);
+       debugfs_create_file(name, S_IRUGO, NULL, edid, &tegra_edid_debug_fops);
+}
+#else
+void tegra_edid_debug_add(struct tegra_edid *edid)
+{
+}
+#endif
+
+#ifdef DEBUG
+static char tegra_edid_dump_buff[16 * 1024];
+
+static void tegra_edid_dump(struct tegra_edid *edid)
+{
+       struct seq_file s;
+       int i;
+       char c;
+
+       memset(&s, 0x0, sizeof(s));
+
+       s.buf = tegra_edid_dump_buff;
+       s.size = sizeof(tegra_edid_dump_buff);
+       s.private = edid;
+
+       tegra_edid_show(&s, NULL);
+
+       i = 0;
+       while (i < s.count ) {
+               if ((s.count - i) > 256) {
+                       c = s.buf[i + 256];
+                       s.buf[i + 256] = 0;
+                       printk("%s", s.buf + i);
+                       s.buf[i + 256] = c;
+               } else {
+                       printk("%s", s.buf + i);
+               }
+               i += 256;
+       }
+}
+#else
+static void tegra_edid_dump(struct tegra_edid *edid)
+{
+}
+#endif
+
+int tegra_edid_read_block(struct tegra_edid *edid, int block, u8 *data)
+{
+       u8 block_buf[] = {block >> 1};
+       u8 cmd_buf[] = {(block & 0x1) * 128};
+       int status;
+       struct i2c_msg msg[] = {
+               {
+                       .addr = 0x30,
+                       .flags = 0,
+                       .len = 1,
+                       .buf = block_buf,
+               },
+               {
+                       .addr = 0x50,
+                       .flags = 0,
+                       .len = 1,
+                       .buf = cmd_buf,
+               },
+               {
+                       .addr = 0x50,
+                       .flags = I2C_M_RD,
+                       .len = 128,
+                       .buf = data,
+               }};
+       struct i2c_msg *m;
+       int msg_len;
+
+       if (block > 1) {
+               msg_len = 3;
+               m = msg;
+       } else {
+               msg_len = 2;
+               m = &msg[1];
+       }
+
+       status = i2c_transfer(edid->client->adapter, m, msg_len);
+
+       if (status < 0)
+               return status;
+
+       if (status != msg_len)
+               return -EIO;
+
+       return 0;
+}
+
+
 int tegra_edid_get_monspecs(struct tegra_edid *edid, struct fb_monspecs *specs)
 {
-       u8 data[256];
        int i;
        int ret;
+       int extension_blocks;
+
+       ret = tegra_edid_read_block(edid, 0, edid->data);
+
+       memset(specs, 0x0, sizeof(struct fb_monspecs));
+       fb_edid_to_monspecs(edid->data, specs);
+       if (specs->modedb == NULL)
+               return -EINVAL;
+
+       extension_blocks = edid->data[0x7e];
 
-       for (i = 0; i < 256; i++) {
-               ret = i2c_smbus_read_byte_data(edid->client, i);
+       for (i = 1; i <= extension_blocks; i++) {
+               ret = tegra_edid_read_block(edid, i, edid->data + i * 128);
                if (ret < 0)
                        break;
 
-               data[i] = ret;
+               if (edid->data[i * 128] == 0x2)
+                       fb_edid_add_monspecs(edid->data + i * 128, specs);
        }
 
-       if (i != 128 && i != 256)
-               return ret;
+       edid->len = i * 128;
 
-       fb_edid_to_monspecs(data, specs);
-       if (i == 256)
-               fb_edid_add_monspecs(data + 128, specs);
+       tegra_edid_dump(edid);
 
        return 0;
 }
@@ -48,36 +198,53 @@ struct tegra_edid *tegra_edid_create(int bus)
 {
        struct tegra_edid *edid;
        struct i2c_adapter *adapter;
+       int err;
 
        edid = kzalloc(sizeof(struct tegra_edid), GFP_KERNEL);
        if (!edid)
                return ERR_PTR(-ENOMEM);
 
+       edid->data = vmalloc(SZ_32K);
+       if (!edid->data) {
+               err = -ENOMEM;
+               goto free_edid;
+       }
        strlcpy(edid->info.type, "tegra_edid", sizeof(edid->info.type));
+       edid->bus = bus;
        edid->info.addr = 0x50;
        edid->info.platform_data = edid;
-       init_waitqueue_head(&edid->wq);
 
        adapter = i2c_get_adapter(bus);
        if (!adapter) {
                pr_err("can't get adpater for bus %d\n", bus);
-               return NULL;
+               err = -EBUSY;
+               goto free_edid;
        }
-       edid->client = i2c_new_device(adapter, &edid->info);
 
+       edid->client = i2c_new_device(adapter, &edid->info);
        i2c_put_adapter(adapter);
 
        if (!edid->client) {
                pr_err("can't create new device\n");
-               return NULL;
+               err = -EBUSY;
+               goto free_edid;
        }
 
+       tegra_edid_debug_add(edid);
+
        return edid;
+
+free_edid:
+       vfree(edid->data);
+       kfree(edid);
+
+       return ERR_PTR(err);
 }
 
 void tegra_edid_destroy(struct tegra_edid *edid)
 {
        i2c_release_client(edid->client);
+       vfree(edid->data);
        kfree(edid);
 }
 

diff --git a/drivers/video/tegra/dc/edid.h b/drivers/video/tegra/dc/edid.h
index eb78abb7e7d8412616005c824a3fc9166f1c7af4..821da90a8b4fe3c926599aaec931a79966d10b89 100644 (file)
--- a/drivers/video/tegra/dc/edid.h
+++ b/drivers/video/tegra/dc/edid.h
@@ -21,13 +21,7 @@
 #include <linux/i2c.h>
 #include <linux/wait.h>
 
-struct tegra_edid {
-       struct i2c_client       *client;
-       struct i2c_board_info   info;
-
-       int                     probed;
-       wait_queue_head_t       wq;
-};
+struct tegra_edid;
 
 struct tegra_edid *tegra_edid_create(int bus);
 void tegra_edid_destroy(struct tegra_edid *edid);