blob: 63dbdb5080f59a641ffd2b1407ba8b34c1f83393 [file] [log] [blame]
From ba02dea17614ea02ad362efc3178c73c3f1d333e Mon Sep 17 00:00:00 2001
From: Wolfram Sang <wsa+renesas@sang-engineering.com>
Date: Sat, 28 Apr 2018 22:01:02 +0200
Subject: [PATCH 1609/1795] i2c: rcar: enhance comment to avoid regressions
Give a clear testcase for people wishing to change this code. It is also
a reminder for me if people ask about it.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
(cherry picked from commit b1437dcb973de79d1f9bca55c6056e8b40ff7ba7)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
drivers/i2c/busses/i2c-rcar.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index c6915b835396..9d8d5b91220f 100644
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -542,6 +542,8 @@ static void rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
* If next received data is the _LAST_, go to STOP phase. Might be
* overwritten by REP START when setting up a new msg. Not elegant
* but the only stable sequence for REP START I have found so far.
+ * If you want to change this code, make sure sending one transfer with
+ * four messages (WR-RD-WR-RD) works!
*/
if (priv->pos + 1 >= msg->len)
rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
--
2.19.0