[PATCH 7.1 07/21] Input: rmi4 - fix register descriptor address calculation

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

7.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dmitry Torokhov <dmitry.torokhov@gmail.com>

commit a98518e72439fd42cbfe641c2896543cb088e3d1 upstream.

When reading the register descriptor, the base address is incremented by
1 to read the presence register block. However, after reading the
presence register block, the address is incorrectly incremented by only
1 byte (++addr) instead of the actual size of the presence block
(size_presence_reg). This causes the subsequent structure block read to
read from the wrong memory location if the presence block is larger than
1 byte.

Fix this by advancing the address by size_presence_reg.

Fixes: 2b6a321da9a2 ("Input: synaptics-rmi4 - add support for Synaptics RMI4 devices")
Cc: stable@vger.kernel.org
Assisted-by: Gemini:gemini-3.1-pro
Link: https://patch.msgid.link/20260505045952.1570713-1-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/input/rmi4/rmi_driver.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/input/rmi4/rmi_driver.c
+++ b/drivers/input/rmi4/rmi_driver.c
@@ -594,7 +594,7 @@ int rmi_read_register_desc(struct rmi_de
 	ret = rmi_read_block(d, addr, buf, size_presence_reg);
 	if (ret)
 		return ret;
-	++addr;
+	addr += size_presence_reg;
 
 	if (buf[0] == 0) {
 		presense_offset = 3;