Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Prashant Malani <pmalani@chromium.org>
To:     linux-kernel@vger.kernel.org
Cc:     Prashant Malani <pmalani@chromium.org>,
        Benson Leung <bleung@chromium.org>,
        Enric Balletbo i Serra <enric.balletbo@collabora.com>,
        Guenter Roeck <groeck@chromium.org>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Mark Brown <broonie@kernel.org>,
        Pi-Hsun Shih <pihsun@chromium.org>,
        Utkarsh Patel <utkarsh.h.patel@intel.com>,
        Yu-Hsuan Hsu <yuhsuan@chromium.org>
Subject: [PATCH] platform/chrome: cros_ec_typec: Handle hard reset
Date:   Wed, 14 Apr 2021 19:14:53 -0700
Message-Id: <20210415021456.1805797-1-pmalani@chromium.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

The Chrome Embedded Controller (EC) generates a hard reset type C event
when a USB Power Delivery (PD) hard reset is encountered. Handle this
event by unregistering the partner and cable on the associated port and
clearing the event flag.

Also update the EC command header to include the new event bit. This bit
is included in the latest version of the Chrome EC headers[1].

[1] https://chromium.googlesource.com/chromiumos/platform/ec/+/refs/heads/main/include/ec_commands.h

Cc: Benson Leung <bleung@chromium.org>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
---
 drivers/platform/chrome/cros_ec_typec.c        | 13 +++++++++++++
 include/linux/platform_data/cros_ec_commands.h |  1 +
 2 files changed, 14 insertions(+)

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index d3df1717a5fd..22052f569f2a 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -905,6 +905,19 @@ static void cros_typec_handle_status(struct cros_typec_data *typec, int port_num
 		return;
 	}
 
+	/* If we got a hard reset, unregister everything and return. */
+	if (resp.events & PD_STATUS_EVENT_HARD_RESET) {
+		cros_typec_remove_partner(typec, port_num);
+		cros_typec_remove_cable(typec, port_num);
+
+		ret = cros_typec_send_clear_event(typec, port_num,
+						  PD_STATUS_EVENT_HARD_RESET);
+		if (ret < 0)
+			dev_warn(typec->dev,
+				 "Failed hard reset event clear, port: %d\n", port_num);
+		return;
+	}
+
 	/* Handle any events appropriately. */
 	if (resp.events & PD_STATUS_EVENT_SOP_DISC_DONE && !typec->ports[port_num]->sop_disc_done) {
 		u16 sop_revision;
diff --git a/include/linux/platform_data/cros_ec_commands.h b/include/linux/platform_data/cros_ec_commands.h
index 5ff8597ceabd..9156078c6fc6 100644
--- a/include/linux/platform_data/cros_ec_commands.h
+++ b/include/linux/platform_data/cros_ec_commands.h
@@ -5678,6 +5678,7 @@ enum tcpc_cc_polarity {
 
 #define PD_STATUS_EVENT_SOP_DISC_DONE		BIT(0)
 #define PD_STATUS_EVENT_SOP_PRIME_DISC_DONE	BIT(1)
+#define PD_STATUS_EVENT_HARD_RESET		BIT(2)
 
 struct ec_params_typec_status {
 	uint8_t port;
-- 
2.31.1.295.g9ea45b61b8-goog