[U-Boot] [PATCH] common/i2c: Add i2c write command
York Sun
yorksun at freescale.com
Sun Sep 16 20:02:30 CEST 2012
Add i2c write command to write data from memory to i2c devices.
Signed-off-by: York Sun <yorksun at freescale.com>
---
common/cmd_i2c.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 50 insertions(+)
diff --git a/common/cmd_i2c.c b/common/cmd_i2c.c
index 2cdc4ed..6099115 100644
--- a/common/cmd_i2c.c
+++ b/common/cmd_i2c.c
@@ -223,6 +223,54 @@ static int do_i2c_read ( cmd_tbl_t *cmdtp, int flag, int argc, char * const argv
return 0;
}
+static int do_i2c_write(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+ u_char chip;
+ uint devaddr, alen, length;
+ u_char *memaddr;
+
+ if (argc != 5)
+ return cmd_usage(cmdtp);
+
+ /*
+ * memaddr is the address where to store things in memory
+ */
+ memaddr = (u_char *)simple_strtoul(argv[1], NULL, 16);
+
+ /*
+ * I2C chip address
+ */
+ chip = simple_strtoul(argv[2], NULL, 16);
+
+ /*
+ * I2C data address within the chip. This can be 1 or
+ * 2 bytes long. Some day it might be 3 bytes long :-).
+ */
+ devaddr = simple_strtoul(argv[3], NULL, 16);
+ alen = get_alen(argv[3]);
+ if (alen > 3)
+ return cmd_usage(cmdtp);
+
+ /*
+ * Length is the number of objects, not number of bytes.
+ */
+ length = simple_strtoul(argv[4], NULL, 16);
+
+ while (length-- > 0) {
+ if (i2c_write(chip, devaddr++, alen, memaddr++, 1) != 0) {
+ puts("Error writing to the chip.\n");
+ return 1;
+ }
+/*
+ * No write delay with FRAM devices.
+ */
+#if !defined(CONFIG_SYS_I2C_FRAM)
+ udelay(11000);
+#endif
+ }
+ return 0;
+}
+
/*
* Syntax:
* i2c md {i2c_chip} {addr}{.0, .1, .2} {len}
@@ -1282,6 +1330,7 @@ static cmd_tbl_t cmd_i2c_sub[] = {
U_BOOT_CMD_MKENT(nm, 2, 1, do_i2c_nm, "", ""),
U_BOOT_CMD_MKENT(probe, 0, 1, do_i2c_probe, "", ""),
U_BOOT_CMD_MKENT(read, 5, 1, do_i2c_read, "", ""),
+ U_BOOT_CMD_MKENT(write, 5, 0, do_i2c_write, "", ""),
U_BOOT_CMD_MKENT(reset, 0, 1, do_i2c_reset, "", ""),
#if defined(CONFIG_CMD_SDRAM)
U_BOOT_CMD_MKENT(sdram, 1, 1, do_sdram, "", ""),
@@ -1333,6 +1382,7 @@ U_BOOT_CMD(
"i2c nm chip address[.0, .1, .2] - write to I2C device (constant address)\n"
"i2c probe - show devices on the I2C bus\n"
"i2c read chip address[.0, .1, .2] length memaddress - read to memory \n"
+ "i2c write memaddress chip address[.0, .1, .2] length - write memory to i2c\n"
"i2c reset - re-init the I2C Controller\n"
#if defined(CONFIG_CMD_SDRAM)
"i2c sdram chip - print SDRAM configuration information\n"
--
1.7.9.5
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