[U-Boot] [PATCH 11/17] edid: Add I2C command for printing the EDID
Simon Glass
sjg at chromium.org
Sat Nov 3 01:27:27 CET 2012
From: Tom Wai-Hong Tam <waihong at chromium.org>
Add a single command to read the EDID information over I2C.
For example:
SMDK5250 # i2c dev 7
Setting bus to 7
SMDK5250 # i2c edid 50
EDID version: 1.4
Product ID code: 305c
Manufacturer: AUO
Serial number: 00000000
Manufactured in week: 0 year: 2011
Video input definition: digital signal, voltage level 0, blank to black
Monitor is non-RGB
Maximum visible display size: 26 cm x 14 cm
Power management features: no active off, no suspend, no standby
Estabilished timings:
Standard timings:
1366x768 60 Hz (detailed)
1366x768 60 Hz (detailed)
Monitor ID: 2VD2K.B116XW
Signed-off-by: Tom Wai-Hong Tam <waihong at chromium.org>
Signed-off-by: Sean Paul <seanpaul at chromium.org>
Signed-off-by: Simon Glass <sjg at chromium.org>
---
README | 7 +++++++
common/cmd_i2c.c | 39 +++++++++++++++++++++++++++++++++++++++
2 files changed, 46 insertions(+), 0 deletions(-)
diff --git a/README b/README
index 31e25fe..daa95cb 100644
--- a/README
+++ b/README
@@ -1465,6 +1465,13 @@ CBFS (Coreboot Filesystem) support
Normally display is black on white background; define
CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
+
+ CONFIG_I2C_EDI
+
+ Enables an 'i2c edid' command which can read EDID
+ information over I2C from an attached LCD display.
+
+
- Splash Screen Support: CONFIG_SPLASH_SCREEN
If this option is set, the environment is checked for
diff --git a/common/cmd_i2c.c b/common/cmd_i2c.c
index 82e63e1..e7f7b55 100644
--- a/common/cmd_i2c.c
+++ b/common/cmd_i2c.c
@@ -78,6 +78,7 @@
#include <common.h>
#include <command.h>
+#include <edid.h>
#include <environment.h>
#include <i2c.h>
#include <malloc.h>
@@ -1246,6 +1247,38 @@ static int do_sdram (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
}
#endif
+/*
+ * Syntax:
+ * i2c edid {i2c_chip}
+ */
+#if defined(CONFIG_I2C_EDID)
+int do_edid(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
+{
+ u_char chip;
+ struct edid1_info edid;
+
+ if (argc < 2) {
+ cmd_usage(cmdtp);
+ return 1;
+ }
+
+ chip = simple_strtoul(argv[1], NULL, 16);
+ if (i2c_read(chip, 0, 1, (uchar *)&edid, sizeof(edid)) != 0) {
+ puts("Error reading EDID content.\n");
+ return 1;
+ }
+
+ if (edid_check_info(&edid)) {
+ puts("Content isn't valid EDID.\n");
+ return 1;
+ }
+
+ edid_print_info(&edid);
+ return 0;
+
+}
+#endif /* CONFIG_I2C_EDID */
+
#if defined(CONFIG_I2C_MUX)
static int do_i2c_add_bus(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
{
@@ -1335,6 +1368,9 @@ static cmd_tbl_t cmd_i2c_sub[] = {
#if defined(CONFIG_I2C_MULTI_BUS)
U_BOOT_CMD_MKENT(dev, 1, 1, do_i2c_bus_num, "", ""),
#endif /* CONFIG_I2C_MULTI_BUS */
+#if defined(CONFIG_I2C_EDID)
+ U_BOOT_CMD_MKENT(edid, 1, 1, do_edid, "", ""),
+#endif /* CONFIG_I2C_EDID */
U_BOOT_CMD_MKENT(loop, 3, 1, do_i2c_loop, "", ""),
U_BOOT_CMD_MKENT(md, 3, 1, do_i2c_md, "", ""),
U_BOOT_CMD_MKENT(mm, 2, 1, do_i2c_mm, "", ""),
@@ -1387,6 +1423,9 @@ U_BOOT_CMD(
#if defined(CONFIG_I2C_MULTI_BUS)
"i2c dev [dev] - show or set current I2C bus\n"
#endif /* CONFIG_I2C_MULTI_BUS */
+#if defined(CONFIG_I2C_EDID)
+ "i2c edid chip - print EDID configuration information\n"
+#endif /* CONFIG_I2C_EDID */
"i2c loop chip address[.0, .1, .2] [# of objects] - looping read of device\n"
"i2c md chip address[.0, .1, .2] [# of objects] - read from I2C device\n"
"i2c mm chip address[.0, .1, .2] - write to I2C device (auto-incrementing)\n"
--
1.7.7.3
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