usb: typec: Add support for UCSI interface

UCSI - USB Type-C Connector System Software Interface - is a
specification that defines set of registers and data
structures for controlling the USB Type-C ports. It's
designed for systems where an embedded controller (EC) is in
charge of the USB Type-C PHY or USB Power Delivery
controller. It is designed for systems with EC, but it is
not limited to them, and for example some USB Power Delivery
controllers will use it as their direct control interface.

With UCSI the EC (or USB PD controller) acts as the port
manager, implementing all USB Type-C and Power Delivery state
machines. The OS can use the interfaces for reading the
status of the ports and controlling basic operations like
role swapping.

The UCSI specification highlights the fact that it does not
define the interface method (PCI/I2C/ACPI/etc.).
Therefore the driver is implemented as library and every
supported interface method needs its own driver. Driver for
ACPI is provided in separate patch following this one.

The initial driver includes support for all required
features from UCSI specification version 1.0 (getting
connector capabilities and status, and support for power and
data role swapping), but none of the optional UCSI features
(alternate modes, power source capabilities, and cable
capabilities).

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/Kconfig

@@ -19,4 +19,6 @@ config TYPEC_WCOVE
 	  To compile this driver as module, choose M here: the module will be
 	  called typec_wcove
 
+source "drivers/usb/typec/ucsi/Kconfig"
+
 endmenu

drivers/usb/typec/Makefile

@@ -1,2 +1,3 @@
 obj-$(CONFIG_TYPEC)		+= typec.o
 obj-$(CONFIG_TYPEC_WCOVE)	+= typec_wcove.o
+obj-$(CONFIG_TYPEC_UCSI)	+= ucsi/

drivers/usb/typec/ucsi/Kconfig

@@ -0,0 +1,23 @@
+config TYPEC_UCSI
+	tristate "USB Type-C Connector System Software Interface driver"
+	depends on !CPU_BIG_ENDIAN
+	select TYPEC
+	help
+	  USB Type-C Connector System Software Interface (UCSI) is a
+	  specification for an interface that allows the operating system to
+	  control the USB Type-C ports. On UCSI system the USB Type-C ports
+	  function autonomously by default, but in order to get the status of
+	  the ports and support basic operations like role swapping, the driver
+	  is required. UCSI is available on most of the new Intel based systems
+	  that are equipped with Embedded Controller and USB Type-C ports.
+
+	  UCSI specification does not define the interface method, so depending
+	  on the platform, ACPI, PCI, I2C, etc. may be used. Therefore this
+	  driver only provides the core part, and separate drivers are needed
+	  for every supported interface method.
+
+	  The UCSI specification can be downloaded from:
+	  http://www.intel.com/content/www/us/en/io/universal-serial-bus/usb-type-c-ucsi-spec.html
+
+	  To compile the driver as a module, choose M here: the module will be
+	  called typec_ucsi.

drivers/usb/typec/ucsi/Makefile

@@ -0,0 +1,7 @@
+CFLAGS_trace.o			:= -I$(src)
+
+obj-$(CONFIG_TYPEC_UCSI)	+= typec_ucsi.o
+
+typec_ucsi-y			:= ucsi.o
+
+typec_ucsi-$(CONFIG_FTRACE)	+= trace.o

drivers/usb/typec/ucsi/debug.h

@@ -0,0 +1,64 @@
+#ifndef __UCSI_DEBUG_H
+#define __UCSI_DEBUG_H
+
+#include "ucsi.h"
+
+static const char * const ucsi_cmd_strs[] = {
+	[0]				= "Unknown command",
+	[UCSI_PPM_RESET]		= "PPM_RESET",
+	[UCSI_CANCEL]			= "CANCEL",
+	[UCSI_CONNECTOR_RESET]		= "CONNECTOR_RESET",
+	[UCSI_ACK_CC_CI]		= "ACK_CC_CI",
+	[UCSI_SET_NOTIFICATION_ENABLE]	= "SET_NOTIFICATION_ENABLE",
+	[UCSI_GET_CAPABILITY]		= "GET_CAPABILITY",
+	[UCSI_GET_CONNECTOR_CAPABILITY]	= "GET_CONNECTOR_CAPABILITY",
+	[UCSI_SET_UOM]			= "SET_UOM",
+	[UCSI_SET_UOR]			= "SET_UOR",
+	[UCSI_SET_PDM]			= "SET_PDM",
+	[UCSI_SET_PDR]			= "SET_PDR",
+	[UCSI_GET_ALTERNATE_MODES]	= "GET_ALTERNATE_MODES",
+	[UCSI_GET_CAM_SUPPORTED]	= "GET_CAM_SUPPORTED",
+	[UCSI_GET_CURRENT_CAM]		= "GET_CURRENT_CAM",
+	[UCSI_SET_NEW_CAM]		= "SET_NEW_CAM",
+	[UCSI_GET_PDOS]			= "GET_PDOS",
+	[UCSI_GET_CABLE_PROPERTY]	= "GET_CABLE_PROPERTY",
+	[UCSI_GET_CONNECTOR_STATUS]	= "GET_CONNECTOR_STATUS",
+	[UCSI_GET_ERROR_STATUS]		= "GET_ERROR_STATUS",
+};
+
+static inline const char *ucsi_cmd_str(u64 raw_cmd)
+{
+	u8 cmd = raw_cmd & GENMASK(7, 0);
+
+	return ucsi_cmd_strs[(cmd >= ARRAY_SIZE(ucsi_cmd_strs)) ? 0 : cmd];
+}
+
+static const char * const ucsi_ack_strs[] = {
+	[0]				= "",
+	[UCSI_ACK_EVENT]		= "event",
+	[UCSI_ACK_CMD]			= "command",
+};
+
+static inline const char *ucsi_ack_str(u8 ack)
+{
+	return ucsi_ack_strs[(ack >= ARRAY_SIZE(ucsi_ack_strs)) ? 0 : ack];
+}
+
+static inline const char *ucsi_cci_str(u32 cci)
+{
+	if (cci & GENMASK(7, 0)) {
+		if (cci & BIT(29))
+			return "Event pending (ACK completed)";
+		if (cci & BIT(31))
+			return "Event pending (command completed)";
+		return "Connector Change";
+	}
+	if (cci & BIT(29))
+		return "ACK completed";
+	if (cci & BIT(31))
+		return "Command completed";
+
+	return "";
+}
+
+#endif /* __UCSI_DEBUG_H */

drivers/usb/typec/ucsi/trace.c

@@ -0,0 +1,2 @@
+#define CREATE_TRACE_POINTS
+#include "trace.h"

drivers/usb/typec/ucsi/trace.h

@@ -0,0 +1,143 @@
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM ucsi
+
+#if !defined(__UCSI_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define __UCSI_TRACE_H
+
+#include <linux/tracepoint.h>
+#include "ucsi.h"
+#include "debug.h"
+
+DECLARE_EVENT_CLASS(ucsi_log_ack,
+	TP_PROTO(u8 ack),
+	TP_ARGS(ack),
+	TP_STRUCT__entry(
+		__field(u8, ack)
+	),
+	TP_fast_assign(
+		__entry->ack = ack;
+	),
+	TP_printk("ACK %s", ucsi_ack_str(__entry->ack))
+);
+
+DEFINE_EVENT(ucsi_log_ack, ucsi_ack,
+	TP_PROTO(u8 ack),
+	TP_ARGS(ack)
+);
+
+DECLARE_EVENT_CLASS(ucsi_log_control,
+	TP_PROTO(struct ucsi_control *ctrl),
+	TP_ARGS(ctrl),
+	TP_STRUCT__entry(
+		__field(u64, ctrl)
+	),
+	TP_fast_assign(
+		__entry->ctrl = ctrl->raw_cmd;
+	),
+	TP_printk("control=%08llx (%s)", __entry->ctrl,
+		ucsi_cmd_str(__entry->ctrl))
+);
+
+DEFINE_EVENT(ucsi_log_control, ucsi_command,
+	TP_PROTO(struct ucsi_control *ctrl),
+	TP_ARGS(ctrl)
+);
+
+DECLARE_EVENT_CLASS(ucsi_log_command,
+	TP_PROTO(struct ucsi_control *ctrl, int ret),
+	TP_ARGS(ctrl, ret),
+	TP_STRUCT__entry(
+		__field(u64, ctrl)
+		__field(int, ret)
+	),
+	TP_fast_assign(
+		__entry->ctrl = ctrl->raw_cmd;
+		__entry->ret = ret;
+	),
+	TP_printk("%s -> %s (err=%d)", ucsi_cmd_str(__entry->ctrl),
+		__entry->ret < 0 ? "FAIL" : "OK",
+		__entry->ret < 0 ? __entry->ret : 0)
+);
+
+DEFINE_EVENT(ucsi_log_command, ucsi_run_command,
+	TP_PROTO(struct ucsi_control *ctrl, int ret),
+	TP_ARGS(ctrl, ret)
+);
+
+DEFINE_EVENT(ucsi_log_command, ucsi_reset_ppm,
+	TP_PROTO(struct ucsi_control *ctrl, int ret),
+	TP_ARGS(ctrl, ret)
+);
+
+DECLARE_EVENT_CLASS(ucsi_log_cci,
+	TP_PROTO(u32 cci),
+	TP_ARGS(cci),
+	TP_STRUCT__entry(
+		__field(u32, cci)
+	),
+	TP_fast_assign(
+		__entry->cci = cci;
+	),
+	TP_printk("CCI=%08x %s", __entry->cci, ucsi_cci_str(__entry->cci))
+);
+
+DEFINE_EVENT(ucsi_log_cci, ucsi_notify,
+	TP_PROTO(u32 cci),
+	TP_ARGS(cci)
+);
+
+DECLARE_EVENT_CLASS(ucsi_log_connector_status,
+	TP_PROTO(int port, struct ucsi_connector_status *status),
+	TP_ARGS(port, status),
+	TP_STRUCT__entry(
+		__field(int, port)
+		__field(u16, change)
+		__field(u8, opmode)
+		__field(u8, connected)
+		__field(u8, pwr_dir)
+		__field(u8, partner_flags)
+		__field(u8, partner_type)
+		__field(u32, request_data_obj)
+		__field(u8, bc_status)
+	),
+	TP_fast_assign(
+		__entry->port = port - 1;
+		__entry->change = status->change;
+		__entry->opmode = status->pwr_op_mode;
+		__entry->connected = status->connected;
+		__entry->pwr_dir = status->pwr_dir;
+		__entry->partner_flags = status->partner_flags;
+		__entry->partner_type = status->partner_type;
+		__entry->request_data_obj = status->request_data_obj;
+		__entry->bc_status = status->bc_status;
+	),
+	TP_printk("port%d status: change=%04x, opmode=%x, connected=%d, "
+		"sourcing=%d, partner_flags=%x, partner_type=%x, "
+		"request_data_obj=%08x, BC status=%x", __entry->port,
+		__entry->change, __entry->opmode, __entry->connected,
+		__entry->pwr_dir, __entry->partner_flags, __entry->partner_type,
+		__entry->request_data_obj, __entry->bc_status)
+);
+
+DEFINE_EVENT(ucsi_log_connector_status, ucsi_connector_change,
+	TP_PROTO(int port, struct ucsi_connector_status *status),
+	TP_ARGS(port, status)
+);
+
+DEFINE_EVENT(ucsi_log_connector_status, ucsi_register_port,
+	TP_PROTO(int port, struct ucsi_connector_status *status),
+	TP_ARGS(port, status)
+);
+
+#endif /* __UCSI_TRACE_H */
+
+/* This part must be outside protection */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE trace
+
+#include <trace/define_trace.h>