linux-kernel - [PATCH 5.4 026/191] Input: st1232 - do not reset the chip too early

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200102215832.776121397@linuxfoundation.org>
Date:   Thu,  2 Jan 2020 23:05:08 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Matthias Fend <Matthias.Fend@...fvision.net>,
        Dmitry Torokhov <dmitry.torokhov@...il.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.4 026/191] Input: st1232 - do not reset the chip too early

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

[ Upstream commit efd7bb08a762d4f6322054c6824bd942971ac563 ]

We should not be putting the chip into reset while interrupts are enabled
and ISR may be running. Fix this by installing a custom devm action and
powering off the device/resetting GPIO line from there. This ensures proper
ordering.

Tested-by: Matthias Fend <Matthias.Fend@...fvision.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/input/touchscreen/st1232.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/input/touchscreen/st1232.c b/drivers/input/touchscreen/st1232.c
index 1139714e72e2..1c5f8875cb79 100644
--- a/drivers/input/touchscreen/st1232.c
+++ b/drivers/input/touchscreen/st1232.c
@@ -149,6 +149,11 @@ static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron)
 		gpiod_set_value_cansleep(ts->reset_gpio, !poweron);
 }
 
+static void st1232_ts_power_off(void *data)
+{
+	st1232_ts_power(data, false);
+}
+
 static const struct st_chip_info st1232_chip_info = {
 	.have_z		= true,
 	.max_x		= 0x31f, /* 800 - 1 */
@@ -229,6 +234,13 @@ static int st1232_ts_probe(struct i2c_client *client,
 
 	st1232_ts_power(ts, true);
 
+	error = devm_add_action_or_reset(&client->dev, st1232_ts_power_off, ts);
+	if (error) {
+		dev_err(&client->dev,
+			"Failed to install power off action: %d\n", error);
+		return error;
+	}
+
 	input_dev->name = "st1232-touchscreen";
 	input_dev->id.bustype = BUS_I2C;
 	input_dev->dev.parent = &client->dev;
@@ -271,15 +283,6 @@ static int st1232_ts_probe(struct i2c_client *client,
 	return 0;
 }
 
-static int st1232_ts_remove(struct i2c_client *client)
-{
-	struct st1232_ts_data *ts = i2c_get_clientdata(client);
-
-	st1232_ts_power(ts, false);
-
-	return 0;
-}
-
 static int __maybe_unused st1232_ts_suspend(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
@@ -329,7 +332,6 @@ MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
 
 static struct i2c_driver st1232_ts_driver = {
 	.probe		= st1232_ts_probe,
-	.remove		= st1232_ts_remove,
 	.id_table	= st1232_ts_id,
 	.driver = {
 		.name	= ST1232_TS_NAME,
-- 
2.20.1