linux-kernel - [PATCH] i2c: designware: Add disable runtime pm quirk

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 for Android: free password hash cracker in your pocket

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

Date:   Tue, 25 Jun 2019 16:30:51 +0800
From:   AceLan Kao <acelan.kao@...onical.com>
To:     Jarkko Nikula <jarkko.nikula@...ux.intel.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Mika Westerberg <mika.westerberg@...ux.intel.com>,
        linux-i2c@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH] i2c: designware: Add disable runtime pm quirk

Dell machines come with goodix touchpad IC suffer from the double click
issue if the Designware I2C adapter enters runtime suspend.

It's because the goodix re-assert the interrupt if host doesn't read the
data within 100ms and designware takes a longer time to wake up from
runtime suspend. In the case, it got a second interrupt during
resuming, so it thinks it's a double click.

There is no simple way to fix this, it's a firmware issue and goodix
agrees to fix this in their firmware on next release, but this issue
still affects the machines that don't come with an updated firmware. So,
add a quirk to mark those machines and avoid the designware from
entering runtime suspend.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=202683

Signed-off-by: AceLan Kao <acelan.kao@...onical.com>
---
 drivers/i2c/busses/i2c-designware-master.c | 30 ++++++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index d464799e40a3..4048a66355f6 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -9,6 +9,7 @@
  * Copyright (C) 2009 Provigent Ltd.
  */
 #include <linux/delay.h>
+#include <linux/dmi.h>
 #include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/export.h>
@@ -22,6 +23,25 @@
 
 #include "i2c-designware-core.h"
 
+static int no_runtime_pm;
+static const struct dmi_system_id i2c_dw_no_runtime_pm[] = {
+	{
+		.ident = "Dell Inspiron 5390",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 5390"),
+		},
+	},
+	{
+		.ident = "Dell Vostro 5390",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 5390"),
+		},
+	},
+	{ }
+};
+
 static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev)
 {
 	/* Configure Tx/Rx FIFO threshold levels */
@@ -424,7 +444,8 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 
 	dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num);
 
-	pm_runtime_get_sync(dev->dev);
+	if (!no_runtime_pm)
+		pm_runtime_get_sync(dev->dev);
 
 	if (dev_WARN_ONCE(dev->dev, dev->suspended, "Transfer while suspended\n")) {
 		ret = -ESHUTDOWN;
@@ -501,7 +522,8 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 
 done_nolock:
 	pm_runtime_mark_last_busy(dev->dev);
-	pm_runtime_put_autosuspend(dev->dev);
+	if (!no_runtime_pm)
+		pm_runtime_put_autosuspend(dev->dev);
 
 	return ret;
 }
@@ -733,6 +755,10 @@ int i2c_dw_probe(struct dw_i2c_dev *dev)
 	if (ret)
 		return ret;
 
+	no_runtime_pm = dmi_check_system(i2c_dw_no_runtime_pm);
+	if (no_runtime_pm)
+		__pm_runtime_disable(dev->dev, true);
+
 	/*
 	 * Increment PM usage count during adapter registration in order to
 	 * avoid possible spurious runtime suspend when adapter device is
-- 
2.17.1