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Sender: "kyletso via sendgmr" <kyletso@kyletso.ntc.corp.google.com>
Date:   Sun, 14 Feb 2021 19:17:30 +0800
Message-Id: <20210214111730.1436506-1-kyletso@google.com>
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Subject: [PATCH v3] usb: typec: tcpm: Export partner Source Capabilities
From:   Kyle Tso <kyletso@google.com>
To:     linux@roeck-us.net, heikki.krogerus@linux.intel.com,
        gregkh@linuxfoundation.org
Cc:     badhri@google.com, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, Kyle Tso <kyletso@google.com>
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Precedence: bulk

Export a function for other drivers to get the partner Source
Capabilities.

Signed-off-by: Kyle Tso <kyletso@google.com>
---
Changes since v1:
- add a put function to free the memory

Changes since v2:
- bring back the function tcpm_copy_pdos

 drivers/usb/typec/tcpm/tcpm.c | 47 +++++++++++++++++++++++++++++++++++
 include/linux/usb/tcpm.h      |  2 ++
 2 files changed, 49 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index be0b6469dd3d..1679c75e5a3d 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -5739,6 +5739,53 @@ static int tcpm_fw_get_caps(struct tcpm_port *port,
 	return 0;
 }
 
+static int tcpm_copy_pdos(u32 *dest_pdo, const u32 *src_pdo, unsigned int nr_pdo)
+{
+	unsigned int i;
+
+	if (nr_pdo > PDO_MAX_OBJECTS)
+		nr_pdo = PDO_MAX_OBJECTS;
+
+	for (i = 0; i < nr_pdo; i++)
+		dest_pdo[i] = src_pdo[i];
+
+	return nr_pdo;
+}
+
+/*
+ * Don't call this function in interrupt context. Caller needs to free the
+ * memory by calling tcpm_put_partner_src_caps.
+ */
+int tcpm_get_partner_src_caps(struct tcpm_port *port, u32 **src_pdo)
+{
+	unsigned int nr_pdo;
+
+	mutex_lock(&port->lock);
+	if (port->nr_source_caps == 0) {
+		mutex_unlock(&port->lock);
+		return -ENODATA;
+	}
+
+	*src_pdo = kcalloc(port->nr_source_caps, sizeof(u32), GFP_KERNEL);
+	if (!src_pdo) {
+		mutex_unlock(&port->lock);
+		return -ENOMEM;
+	}
+
+	nr_pdo = tcpm_copy_pdos(*src_pdo, port->source_caps,
+				port->nr_source_caps);
+	mutex_unlock(&port->lock);
+	return nr_pdo;
+}
+EXPORT_SYMBOL_GPL(tcpm_get_partner_src_caps);
+
+void tcpm_put_partner_src_caps(u32 **src_pdo)
+{
+	kfree(*src_pdo);
+	*src_pdo = NULL;
+}
+EXPORT_SYMBOL_GPL(tcpm_put_partner_src_caps);
+
 /* Power Supply access to expose source power information */
 enum tcpm_psy_online_states {
 	TCPM_PSY_OFFLINE = 0,
diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h
index 42fcfbe10590..f83d9ff89a13 100644
--- a/include/linux/usb/tcpm.h
+++ b/include/linux/usb/tcpm.h
@@ -161,5 +161,7 @@ void tcpm_pd_transmit_complete(struct tcpm_port *port,
 			       enum tcpm_transmit_status status);
 void tcpm_pd_hard_reset(struct tcpm_port *port);
 void tcpm_tcpc_reset(struct tcpm_port *port);
+int tcpm_get_partner_src_caps(struct tcpm_port *port, u32 **pdo);
+void tcpm_put_partner_src_caps(u32 **pdo);
 
 #endif /* __LINUX_USB_TCPM_H */
-- 
2.30.0.478.g8a0d178c01-goog