[PATCH v2 1/3] usb: typec: ucsi: Provide interface for UCSI transport

[Pavan Holla <pholla@chromium.org>]

The ucsi.h include can be used by driver implementations that
provide transport for UCSI commands.

Signed-off-by: Pavan Holla <pholla@chromium.org>
---
 MAINTAINERS              |  1 +
 include/linux/usb/ucsi.h | 66 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index aa3b947fb080..e799d67a8fa5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -22987,6 +22987,7 @@ F:	Documentation/ABI/testing/sysfs-class-typec
 F:	Documentation/driver-api/usb/typec.rst
 F:	drivers/usb/typec/
 F:	include/linux/usb/typec.h
+F:	include/linux/usb/ucsi.h
 
 USB TYPEC INTEL PMC MUX DRIVER
 M:	Heikki Krogerus <heikki.krogerus@linux.intel.com>
diff --git a/include/linux/usb/ucsi.h b/include/linux/usb/ucsi.h
new file mode 100644
index 000000000000..3ec1db968070
--- /dev/null
+++ b/include/linux/usb/ucsi.h
@@ -0,0 +1,66 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __LINUX_USB_UCSI_H
+#define __LINUX_USB_UCSI_H
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/types.h>
+
+/* -------------------------------------------------------------------------- */
+
+struct ucsi;
+struct ucsi_altmode;
+
+/* UCSI offsets (Bytes) */
+#define UCSI_VERSION			0
+#define UCSI_CCI			4
+#define UCSI_CONTROL			8
+#define UCSI_MESSAGE_IN			16
+#define UCSI_MESSAGE_OUT		32
+#define UCSIv2_MESSAGE_OUT		272
+
+/* Command Status and Connector Change Indication (CCI) bits */
+#define UCSI_CCI_CONNECTOR(_c_)		(((_c_) & GENMASK(7, 1)) >> 1)
+#define UCSI_CCI_LENGTH(_c_)		(((_c_) & GENMASK(15, 8)) >> 8)
+#define UCSI_CCI_NOT_SUPPORTED		BIT(25)
+#define UCSI_CCI_CANCEL_COMPLETE	BIT(26)
+#define UCSI_CCI_RESET_COMPLETE		BIT(27)
+#define UCSI_CCI_BUSY			BIT(28)
+#define UCSI_CCI_ACK_COMPLETE		BIT(29)
+#define UCSI_CCI_ERROR			BIT(30)
+#define UCSI_CCI_COMMAND_COMPLETE	BIT(31)
+
+/**
+ * struct ucsi_operations - UCSI I/O operations
+ * @read: Read operation
+ * @sync_write: Blocking write operation
+ * @async_write: Non-blocking write operation
+ * @update_altmodes: Squashes duplicate DP altmodes
+ *
+ * Read and write routines for UCSI interface. @sync_write must wait for the
+ * Command Completion Event from the PPM before returning, and @async_write must
+ * return immediately after sending the data to the PPM.
+ */
+struct ucsi_operations {
+	int (*read)(struct ucsi *ucsi, unsigned int offset,
+		    void *val, size_t val_len);
+	int (*sync_write)(struct ucsi *ucsi, unsigned int offset,
+			  const void *val, size_t val_len);
+	int (*async_write)(struct ucsi *ucsi, unsigned int offset,
+			   const void *val, size_t val_len);
+	bool (*update_altmodes)(struct ucsi *ucsi, struct ucsi_altmode *orig,
+				struct ucsi_altmode *updated);
+};
+
+struct ucsi *ucsi_create(struct device *dev, const struct ucsi_operations *ops);
+void ucsi_destroy(struct ucsi *ucsi);
+int ucsi_register(struct ucsi *ucsi);
+void ucsi_unregister(struct ucsi *ucsi);
+int ucsi_resume(struct ucsi *ucsi);
+void *ucsi_get_drvdata(struct ucsi *ucsi);
+void ucsi_set_drvdata(struct ucsi *ucsi, void *data);
+
+void ucsi_connector_change(struct ucsi *ucsi, u8 num);
+
+#endif /* __LINUX_USB_UCSI_H */

-- 
2.44.0.396.g6e790dbe36-goog