[PATCH 4.19 28/92] Revert "Input: synaptics-rmi4 - dont increment rmiaddr for SMBus transfers"

From: Greg Kroah-Hartman
Date: Tue Jan 28 2020 - 09:32:04 EST


From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>

commit 8ff771f8c8d55d95f102cf88a970e541a8bd6bcf upstream.

This reverts commit a284e11c371e446371675668d8c8120a27227339.

This causes problems (drifting cursor) with at least the F11 function that
reads more than 32 bytes.

The real issue is in the F54 driver, and so this should be fixed there, and
not in rmi_smbus.c.

So first revert this bad commit, then fix the real problem in F54 in another
patch.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Reported-by: Timo Kaufmann <timokau@xxxxxxxx>
Fixes: a284e11c371e ("Input: synaptics-rmi4 - don't increment rmiaddr for SMBus transfers")
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20200115124819.3191024-2-hverkuil-cisco@xxxxxxxxx
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/input/rmi4/rmi_smbus.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/input/rmi4/rmi_smbus.c
+++ b/drivers/input/rmi4/rmi_smbus.c
@@ -166,6 +166,7 @@ static int rmi_smb_write_block(struct rm
/* prepare to write next block of bytes */
cur_len -= SMB_MAX_COUNT;
databuff += SMB_MAX_COUNT;
+ rmiaddr += SMB_MAX_COUNT;
}
exit:
mutex_unlock(&rmi_smb->page_mutex);
@@ -217,6 +218,7 @@ static int rmi_smb_read_block(struct rmi
/* prepare to read next block of bytes */
cur_len -= SMB_MAX_COUNT;
databuff += SMB_MAX_COUNT;
+ rmiaddr += SMB_MAX_COUNT;
}

retval = 0;