usb: typec: Add driver for DisplayPort alternate mode

DisplayPort USB Type-C Alt Mode allows DisplayPort displays
and adapters to be attached to the USB Type-C ports on the
system.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 95 insertions, 0 deletions

diff --git a/include/linux/usb/typec_dp.h b/include/linux/usb/typec_dp.h
new file mode 100644
index 000000000000..55ae781d60a9
--- /dev/null
+++ b/include/linux/usb/typec_dp.h
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __USB_TYPEC_DP_H
+#define __USB_TYPEC_DP_H
+
+#include <linux/usb/typec_altmode.h>
+
+#define USB_TYPEC_DP_SID	0xff01
+#define USB_TYPEC_DP_MODE	1
+
+/*
+ * Connector states matching the pin assignments in DisplayPort Alt Mode
+ * Specification.
+ *
+ * These values are meant primarily to be used by the mux drivers, but they are
+ * also used as the "value" part in the alternate mode notification chain, so
+ * receivers of those notifications will always see them.
+ *
+ * Note. DisplayPort USB Type-C Alt Mode Specification version 1.0b deprecated
+ * pin assignments A, B and F, but they are still defined here for legacy
+ * purposes.
+ */
+enum {
+	TYPEC_DP_STATE_A = TYPEC_STATE_MODAL,	/* Not supported after v1.0b */
+	TYPEC_DP_STATE_B,			/* Not supported after v1.0b */
+	TYPEC_DP_STATE_C,
+	TYPEC_DP_STATE_D,
+	TYPEC_DP_STATE_E,
+	TYPEC_DP_STATE_F,			/* Not supported after v1.0b */
+};
+
+/*
+ * struct typec_displayport_data - DisplayPort Alt Mode specific data
+ * @status: Status Update command VDO content
+ * @conf: Configure command VDO content
+ *
+ * This structure is delivered as the data part with the notifications. It
+ * contains the VDOs from the two DisplayPort Type-C alternate mode specific
+ * commands: Status Update and Configure.
+ *
+ * @status will show for example the status of the HPD signal.
+ */
+struct typec_displayport_data {
+	u32 status;
+	u32 conf;
+};
+
+enum {
+	DP_PIN_ASSIGN_A, /* Not supported after v1.0b */
+	DP_PIN_ASSIGN_B, /* Not supported after v1.0b */
+	DP_PIN_ASSIGN_C,
+	DP_PIN_ASSIGN_D,
+	DP_PIN_ASSIGN_E,
+	DP_PIN_ASSIGN_F, /* Not supported after v1.0b */
+};
+
+/* DisplayPort alt mode specific commands */
+#define DP_CMD_STATUS_UPDATE		VDO_CMD_VENDOR(0)
+#define DP_CMD_CONFIGURE		VDO_CMD_VENDOR(1)
+
+/* DisplayPort Capabilities VDO bits (returned with Discover Modes) */
+#define DP_CAP_CAPABILITY(_cap_)	((_cap_) & 3)
+#define   DP_CAP_UFP_D			1
+#define   DP_CAP_DFP_D			2
+#define   DP_CAP_DFP_D_AND_UFP_D	3
+#define DP_CAP_DP_SIGNALING		BIT(2) /* Always set */
+#define DP_CAP_GEN2			BIT(3) /* Reserved after v1.0b */
+#define DP_CAP_RECEPTACLE		BIT(6)
+#define DP_CAP_USB			BIT(7)
+#define DP_CAP_DFP_D_PIN_ASSIGN(_cap_)	(((_cap_) & GENMASK(15, 8)) >> 8)
+#define DP_CAP_UFP_D_PIN_ASSIGN(_cap_)	(((_cap_) & GENMASK(23, 16)) >> 16)
+
+/* DisplayPort Status Update VDO bits */
+#define DP_STATUS_CONNECTION(_status_)	((_status_) & 3)
+#define   DP_STATUS_CON_DISABLED	0
+#define   DP_STATUS_CON_DFP_D		1
+#define   DP_STATUS_CON_UFP_D		2
+#define   DP_STATUS_CON_BOTH		3
+#define DP_STATUS_POWER_LOW		BIT(2)
+#define DP_STATUS_ENABLED		BIT(3)
+#define DP_STATUS_PREFER_MULTI_FUNC	BIT(4)
+#define DP_STATUS_SWITCH_TO_USB		BIT(5)
+#define DP_STATUS_EXIT_DP_MODE		BIT(6)
+#define DP_STATUS_HPD_STATE		BIT(7) /* 0 = HPD_Low, 1 = HPD_High */
+#define DP_STATUS_IRQ_HPD		BIT(8)
+
+/* DisplayPort Configurations VDO bits */
+#define DP_CONF_CURRENTLY(_conf_)	((_conf_) & 3)
+#define DP_CONF_UFP_U_AS_DFP_D		BIT(0)
+#define DP_CONF_UFP_U_AS_UFP_D		BIT(1)
+#define DP_CONF_SIGNALING_DP		BIT(2)
+#define DP_CONF_SIGNALING_GEN_2		BIT(3) /* Reserved after v1.0b */
+#define DP_CONF_PIN_ASSIGNEMENT_SHIFT	8
+#define DP_CONF_PIN_ASSIGNEMENT_MASK	GENMASK(15, 8)
+
+#endif /* __USB_TYPEC_DP_H */