[PATCH 5/5] input/rmi4/rmi_smbus.c: don't increment rmiaddr in rmi_smb_read_block()

From: Hans Verkuil <hverkuil-cisco@xs4all.nl>
To: linux-media@vger.kernel.org
Cc: linux-input@vger.kernel.org,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	Nick Dyer <nick@shmanahar.org>,
	Lucas Stach <l.stach@pengutronix.de>,
	Christopher Heiny <cheiny@synaptics.com>,
	Vandana BN <bnvandana@gmail.com>,
	Hans Verkuil <hverkuil-cisco@xs4all.nl>
Subject: [PATCH 5/5] input/rmi4/rmi_smbus.c: don't increment rmiaddr in rmi_smb_read_block()
Date: Tue, 19 Nov 2019 11:51:18 +0100	[thread overview]
Message-ID: <20191119105118.54285-6-hverkuil-cisco@xs4all.nl> (raw)
In-Reply-To: <20191119105118.54285-1-hverkuil-cisco@xs4all.nl>

This increment of rmi_smbus causes garbage to be returned.
The first read of SMB_MAX_COUNT bytes is fine, but after that
it is nonsense. Trial-and-error showed that by dropping the
increment of rmiaddr everything is fine and the F54 function
properly works.

Even going back to the original code when F54 was added, I
could not make it work without this patch. So I do not understand
how this ever worked.

My guess is that the same change is needed in rmi_smb_write_block,
but I wouldn't know how to test this.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
---
 drivers/input/rmi4/rmi_smbus.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/input/rmi4/rmi_smbus.c b/drivers/input/rmi4/rmi_smbus.c
index 2407ea43de59..79ecea5edacc 100644
--- a/drivers/input/rmi4/rmi_smbus.c
+++ b/drivers/input/rmi4/rmi_smbus.c
@@ -215,7 +215,6 @@ static int rmi_smb_read_block(struct rmi_transport_dev *xport, u16 rmiaddr,
 		/* prepare to read next block of bytes */
 		cur_len -= SMB_MAX_COUNT;
 		databuff += SMB_MAX_COUNT;
-		rmiaddr += SMB_MAX_COUNT;
 	}
 
 	retval = 0;
-- 
2.23.0

