mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Antony Pavlov <antonynpavlov@gmail.com>
To: barebox@lists.infradead.org
Subject: [RFC] commands: i2c_write: enable raw write to address
Date: Thu,  8 Feb 2018 10:48:56 +0300	[thread overview]
Message-ID: <20180208074856.3701-1-antonynpavlov@gmail.com> (raw)

Sometimes for communication with a simple I2C devices
(e.g. PCF8574 or TM1650) it's necessary to send only
one data byte into the I2C device.
Current i2c_write command makes this impossible because
you can't just pass 'device address' and 'register number'
(or 'device address' and 'one data byte') to the command.
You always have to pass all three parameters:
'device address', 'register number' and 'data'.

This commit fixes the problem.

Sample usage:

  barebox@barebox sandbox:/ i2c_write -a 0x24 0x01

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
---
 commands/i2c.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/commands/i2c.c b/commands/i2c.c
index b74c53509f..21c39fe5af 100644
--- a/commands/i2c.c
+++ b/commands/i2c.c
@@ -115,7 +115,7 @@ static int do_i2c_write(int argc, char *argv[])
 
 	count = argc - optind;
 
-	if ((addr < 0) || (reg < 0) || (count == 0) || (addr > 0x7F))
+	if ((addr < 0) || (count == 0) || (addr > 0x7F))
 		return COMMAND_ERROR_USAGE;
 
 	adapter = i2c_get_adapter(bus);
@@ -131,7 +131,11 @@ static int do_i2c_write(int argc, char *argv[])
 	for (i = 0; i < count; i++)
 		*(buf + i) = (char) simple_strtol(argv[optind+i], NULL, 0);
 
-	ret = i2c_write_reg(&client, reg | wide, buf, count);
+	if (reg > 0) {
+		ret = i2c_write_reg(&client, reg | wide, buf, count);
+	} else {
+		ret = i2c_master_send(&client, buf, count);
+	}
 	if (ret != count) {
 		if (verbose)
 			printf("write aborted, count(%i) != writestatus(%i)\n",
-- 
2.15.1


_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox

             reply	other threads:[~2018-02-08  7:49 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-08  7:48 Antony Pavlov [this message]
2018-02-09  8:36 ` Sascha Hauer
2018-02-09 11:22   ` Antony Pavlov
2018-02-13  8:19     ` Sascha Hauer
2018-02-14  6:19       ` Antony Pavlov
2018-02-16  7:53         ` Sascha Hauer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180208074856.3701-1-antonynpavlov@gmail.com \
    --to=antonynpavlov@gmail.com \
    --cc=barebox@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox