[WIP] ec/system76/ec: Implement USB-C DP HPD

Change-Id: I0487b761a5a83b0a1897c92416d0d81219303341
Signed-off-by: Tim Crawford <tcrawford@system76.com>

src/ec/system76/ec/Makefile.mk

@@ -5,6 +5,7 @@ all-y += system76_ec.c
 
 ramstage-y += smbios.c
 ramstage-$(CONFIG_EC_SYSTEM76_EC_LOCKDOWN) += lockdown.c
+ramstage-y += usbc_mux.c
 
 smm-$(CONFIG_DEBUG_SMI) += system76_ec.c
 

src/ec/system76/ec/usbc_mux.c

@@ -0,0 +1,132 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include "system76_ec.h"
+#include <console/console.h>
+#include <delay.h>
+#include <device/usbc_mux.h>
+#include <timer.h>
+#include <types.h>
+
+#define CMD_USBC_MUX_INFO 23
+
+enum usbc_mux_flags {
+	USBC_MUX_DP = BIT(0),
+	USBC_MUX_USB = BIT(1),
+	USBC_MUX_CABLE = BIT(2),
+	USBC_MUX_POLARITY = BIT(3),
+	USBC_MUX_HPD_LVL = BIT(4),
+	USBC_MUX_HPD_IRQ = BIT(5),
+	USBC_MUX_UFP = BIT(6),
+	USBC_MUX_DBG_ACC = BIT(7),
+};
+
+static int system76_ec_get_mux_info(int port, struct usbc_mux_info *info)
+{
+	uint8_t request[1] = { port };
+	uint8_t reply[3] = { 0 };
+	uint8_t flags;
+	uint8_t pin_mode;
+	bool res;
+
+	if (!info)
+		return -1;
+
+	res = system76_ec_cmd(CMD_USBC_MUX_INFO, request, ARRAY_SIZE(request),
+			reply, ARRAY_SIZE(reply));
+	if (!res)
+		return -1;
+
+	flags = reply[1];
+	pin_mode = reply[2];
+
+	info->dp = !!(flags & USBC_MUX_DP);
+	info->usb = !!(flags & USBC_MUX_USB);
+	info->cable = !!(flags & USBC_MUX_CABLE);
+	info->polarity = !!(flags & USBC_MUX_POLARITY);
+	info->hpd_lvl = !!(flags & USBC_MUX_HPD_LVL);
+	info->hpd_irq = !!(flags & USBC_MUX_HPD_IRQ);
+	info->ufp = !!(flags & USBC_MUX_UFP);
+	info->dbg_acc = !!(flags & USBC_MUX_DBG_ACC);
+	info->dp_pin_mode = pin_mode;
+
+	printk(BIOS_SPEW, "%s: dp=%u, usb=%u\n", __func__, info->dp, info->usb);
+	printk(BIOS_SPEW, "%s: cable=%u, polarity=%u\n", __func__, info->cable, info->polarity);
+	printk(BIOS_SPEW, "%s: hpd_lvl=%u, hpd_irq=%u\n", __func__, info->hpd_lvl, info->hpd_irq);
+	printk(BIOS_SPEW, "%s: ufp=%u, dbg_acc=%u\n", __func__, info->ufp, info->dbg_acc);
+	printk(BIOS_SPEW, "%s: pin_mode=0x%x\n", __func__, info->dp_pin_mode);
+
+	return 0;
+}
+
+static int system76_ec_wait_for_connection(long timeout_ms)
+{
+	// TODO
+	return 1;
+}
+
+static int system76_ec_enter_dp_mode(int port)
+{
+	// TODO
+	return 0;
+}
+
+static int system76_ec_wait_for_dp_mode_entry(int port, long timeout_ms)
+{
+	struct usbc_mux_info info;
+
+	if (system76_ec_get_mux_info(port, &info) < 0) {
+		printk(BIOS_WARNING, "%s: could not get usbc mux info\n", __func__);
+		return -1;
+	}
+
+	if (!info.dp) {
+		printk(BIOS_WARNING, "DP mode not ready\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int system76_ec_wait_for_hpd(int port, long timeout_ms)
+{
+	struct usbc_mux_info info;
+	struct stopwatch sw;
+
+	stopwatch_init_msecs_expire(&sw, timeout_ms);
+	while (1) {
+		if (system76_ec_get_mux_info(port, &info) < 0) {
+			printk(BIOS_WARNING, "%s: could not get usbc mux info\n", __func__);
+			return -1;
+		}
+
+		if (info.hpd_lvl)
+			break;
+
+		if (stopwatch_expired(&sw)) {
+			printk(BIOS_WARNING, "HPD not ready after %ldms\n", timeout_ms);
+			return -1;
+		}
+
+		mdelay(100);
+	}
+
+	printk(BIOS_INFO, "HPD ready after %lldms\n", stopwatch_duration_msecs(&sw));
+	return 0;
+}
+
+static const struct usbc_ops system76_ec_usbc_ops = {
+	.mux_ops = {
+		.get_mux_info = system76_ec_get_mux_info,
+	},
+	.dp_ops = {
+		.wait_for_connection = system76_ec_wait_for_connection,
+		.enter_dp_mode = system76_ec_enter_dp_mode,
+		.wait_for_dp_mode_entry = system76_ec_wait_for_dp_mode_entry,
+		.wait_for_hpd = system76_ec_wait_for_hpd,
+	},
+};
+
+const struct usbc_ops *usbc_get_ops(void)
+{
+	return &system76_ec_usbc_ops;
+}

src/include/device/usbc_mux.h

@@ -3,6 +3,9 @@
 #ifndef __USBC_MUX_H__
 #define __USBC_MUX_H__
 
+#include <stdbool.h>
+#include <stdint.h>
+
 /* struct to hold all USB-C mux related variables */
 struct usbc_mux_info {
 	bool dp; /* DP connected */

src/mainboard/system76/adl/Kconfig

@@ -11,6 +11,8 @@ config BOARD_SYSTEM76_ADL_COMMON
 	select DRIVERS_INTEL_USB4_RETIMER
 	select EC_SYSTEM76_EC
 	select EC_SYSTEM76_EC_LOCKDOWN
+	select ENABLE_TCSS_DISPLAY_DETECTION
+	select ENABLE_TCSS_USB_DETECTION
 	select HAVE_ACPI_RESUME
 	select HAVE_ACPI_TABLES
 	select HAVE_CMOS_DEFAULT

src/mainboard/system76/rpl/Kconfig

@@ -9,6 +9,8 @@ config BOARD_SYSTEM76_RPL_COMMON
 	select DRIVERS_I2C_HID
 	select EC_SYSTEM76_EC
 	select EC_SYSTEM76_EC_LOCKDOWN
+	select ENABLE_TCSS_DISPLAY_DETECTION
+	select ENABLE_TCSS_USB_DETECTION
 	select HAVE_ACPI_RESUME
 	select HAVE_ACPI_TABLES
 	select HAVE_CMOS_DEFAULT