Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Daisuke Nojiri <dnojiri@chromium.org>
To:     Sebastian Reichel <sre@kernel.org>
Cc:     linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
        Daisuke Nojiri <dnojiri@chromium.org>
Subject: [PATCH] cros_pchg: Sync port status on resume
Date:   Mon, 17 Apr 2023 15:16:10 -0700
Message-ID: <20230417221610.1507341-1-dnojiri@chromium.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

When a stylus is removed (or attached) during suspend, the device detach
(or attach) events can be lost. This patch makes the peripheral device
charge driver retrieve the latest status from the EC on resume.

BUG=b:276414488
TEST=Redrix

Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
---
 .../power/supply/cros_peripheral_charger.c    | 25 ++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/power/supply/cros_peripheral_charger.c b/drivers/power/supply/cros_peripheral_charger.c
index 1379afd9698d..a204f2355be4 100644
--- a/drivers/power/supply/cros_peripheral_charger.c
+++ b/drivers/power/supply/cros_peripheral_charger.c
@@ -227,8 +227,7 @@ static int cros_pchg_get_prop(struct power_supply *psy,
 	return 0;
 }
 
-static int cros_pchg_event(const struct charger_data *charger,
-			   unsigned long host_event)
+static int cros_pchg_event(const struct charger_data *charger)
 {
 	int i;
 
@@ -256,7 +255,7 @@ static int cros_ec_notify(struct notifier_block *nb,
 	if (!(host_event & EC_MKBP_PCHG_DEVICE_EVENT))
 		return NOTIFY_DONE;
 
-	return cros_pchg_event(charger, host_event);
+	return cros_pchg_event(charger);
 }
 
 static int cros_pchg_probe(struct platform_device *pdev)
@@ -281,6 +280,8 @@ static int cros_pchg_probe(struct platform_device *pdev)
 	charger->ec_dev = ec_dev;
 	charger->ec_device = ec_device;
 
+	platform_set_drvdata(pdev, charger);
+
 	ret = cros_pchg_port_count(charger);
 	if (ret <= 0) {
 		/*
@@ -349,9 +350,27 @@ static int cros_pchg_probe(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int __maybe_unused cros_pchg_resume(struct device *dev)
+{
+	struct charger_data *charger = dev_get_drvdata(dev);
+
+	/*
+	 * Sync all ports on resume in case reports from EC are lost during
+	 * the last suspend.
+	 */
+	cros_pchg_event(charger);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(cros_pchg_pm_ops, NULL, cros_pchg_resume);
+
 static struct platform_driver cros_pchg_driver = {
 	.driver = {
 		.name = DRV_NAME,
+		.pm = &cros_pchg_pm_ops,
 	},
 	.probe = cros_pchg_probe
 };
-- 
2.39.2