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* [PATCH 1/2] i2c_probe: limit slave addresses to [0x04, 0x77]
@ 2019-01-25 20:59 Uwe Kleine-König
  2019-01-25 20:59 ` [PATCH 2/2] i2c_probe: Use a quick write transfer instead of writing a zero Uwe Kleine-König
  2019-01-28  9:01 ` [PATCH 1/2] i2c_probe: limit slave addresses to [0x04, 0x77] Sascha Hauer
  0 siblings, 2 replies; 3+ messages in thread
From: Uwe Kleine-König @ 2019-01-25 20:59 UTC (permalink / raw)
  To: barebox

Adresses below 0x04 and above 0x77 are reserved in the i2c bus
specification, so don't probe these addresses unless requested
explicitly.

Also do more strict boundary checking:

 - ensure start address is greater or equal to zero;
 - don't decrease stopaddr after checking it being greater or equal to
   startaddr.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 commands/i2c.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/commands/i2c.c b/commands/i2c.c
index 2f7f820d4d55..65ff7378ec14 100644
--- a/commands/i2c.c
+++ b/commands/i2c.c
@@ -44,7 +44,7 @@ static void i2c_probe_range(struct i2c_adapter *adapter, int startaddr, int stop
 static int do_i2c_probe(int argc, char *argv[])
 {
 	struct i2c_adapter *adapter = NULL;
-	int startaddr = 0, stopaddr = 0x7f;
+	int startaddr = 4, stopaddr = 0x77;
 
 	if (argc > 1) {
 		adapter = i2c_get_adapter(simple_strtoul(argv[1], NULL, 0));
@@ -57,13 +57,15 @@ static int do_i2c_probe(int argc, char *argv[])
 	if (argc > 3)
 		stopaddr = simple_strtol(argv[3], NULL, 0);
 
+	if (stopaddr > 0x7f)
+		stopaddr = 0x7f;
+
+	if (startaddr < 0)
+		startaddr = 0;
 
 	if (startaddr > stopaddr)
 		return COMMAND_ERROR_USAGE;
 
-	if (stopaddr > 0x7F)
-		stopaddr = 0x7F;
-
 	if (adapter) {
 		i2c_probe_range(adapter, startaddr, stopaddr);
 	} else {
-- 
2.20.1


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end of thread, other threads:[~2019-01-28  9:01 UTC | newest]

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-- links below jump to the message on this page --
2019-01-25 20:59 [PATCH 1/2] i2c_probe: limit slave addresses to [0x04, 0x77] Uwe Kleine-König
2019-01-25 20:59 ` [PATCH 2/2] i2c_probe: Use a quick write transfer instead of writing a zero Uwe Kleine-König
2019-01-28  9:01 ` [PATCH 1/2] i2c_probe: limit slave addresses to [0x04, 0x77] Sascha Hauer

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