drivers/usb: Add chip driver for external USB hub
Add chip driver for soldered down external USB hub. This driver adds
ACPI objects for the hub and any downstream facing ports.
BUG=b:227761300
TEST=Build and boot to OS in Skyrim. Ensure that the hub and any
configured ports have ACPI devices defined in SSDT.
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@google.com>
Change-Id: I11d7ccc42d3dce8e136eb771f120825980e5c027
Reviewed-on: https://review.coreboot.org/c/coreboot/+/63968
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/drivers/usb/hub/Kconfig b/src/drivers/usb/hub/Kconfig
new file mode 100644
index 0000000..32eb7c5
--- /dev/null
+++ b/src/drivers/usb/hub/Kconfig
@@ -0,0 +1,8 @@
+config DRIVERS_USB_HUB
+ bool
+ default n
+ depends on HAVE_ACPI_TABLES
+ help
+ This driver is for soldered down USB Hub in the mainboard. When enabled,
+ this driver will add ACPI support for the USB hub and any devices on the
+ downstream facing ports.
diff --git a/src/drivers/usb/hub/Makefile.inc b/src/drivers/usb/hub/Makefile.inc
new file mode 100644
index 0000000..a64d622
--- /dev/null
+++ b/src/drivers/usb/hub/Makefile.inc
@@ -0,0 +1 @@
+ramstage-$(CONFIG_DRIVERS_USB_HUB) += acpi.c
diff --git a/src/drivers/usb/hub/acpi.c b/src/drivers/usb/hub/acpi.c
new file mode 100644
index 0000000..347e25e
--- /dev/null
+++ b/src/drivers/usb/hub/acpi.c
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <acpi/acpigen.h>
+#include <acpi/acpi_device.h>
+#include <stdlib.h>
+
+#include "chip.h"
+
+static const char *usb_hub_acpi_name(const struct device *dev)
+{
+ char *name;
+ const char *pattern;
+
+ /* USB ACPI driver does not have acpi_name operation defined. Hence return
+ the ACPI name for both the hub and any downstream facing ports. */
+ switch (dev->path.usb.port_type) {
+ case 0:
+ return "EHUB";
+ case 2:
+ pattern = "HS%02d";
+ break;
+ case 3:
+ pattern = "SS%02d";
+ break;
+ default:
+ return NULL;
+ }
+
+ name = malloc(ACPI_NAME_BUFFER_SIZE);
+ snprintf(name, ACPI_NAME_BUFFER_SIZE, pattern, dev->path.usb.port_id + 1);
+ name[4] = '\0';
+
+ return name;
+}
+
+static void usb_hub_add_ports(const struct device *dev)
+{
+ const struct drivers_usb_hub_config *config = config_of(dev);
+ struct device *port = NULL;
+ unsigned int child_count = 0;
+
+ while ((port = dev_bus_each_child(dev->link_list, port)) != NULL) {
+ if (child_count++ >= config->port_count) {
+ printk(BIOS_WARNING, "%s cannot be added. Port Count limit reached.\n",
+ dev_name(port));
+ continue;
+ }
+ acpigen_write_device(usb_hub_acpi_name(port));
+ acpigen_write_name_byte("_ADR", port->path.usb.port_id + 1);
+ acpigen_write_device_end();
+ }
+}
+
+static void usb_hub_acpi_fill_ssdt(const struct device *dev)
+{
+ const struct drivers_usb_hub_config *config = config_of(dev);
+ const char *scope = acpi_device_scope(dev);
+ const char *name = acpi_device_name(dev);
+
+ acpigen_write_scope(scope);
+ acpigen_write_device(name);
+ acpigen_write_ADR(0);
+ if (config->name)
+ acpigen_write_name_string("_DDN", config->name);
+ if (config->desc)
+ acpigen_write_name_unicode("_STR", config->desc);
+ usb_hub_add_ports(dev);
+ acpigen_write_device_end();
+ acpigen_write_scope_end();
+}
+
+static struct device_operations usb_hub_ops = {
+ .read_resources = noop_read_resources,
+ .set_resources = noop_set_resources,
+ .scan_bus = scan_static_bus,
+ .acpi_fill_ssdt = usb_hub_acpi_fill_ssdt,
+ .acpi_name = usb_hub_acpi_name
+};
+
+static void usb_hub_acpi_enable(struct device *dev)
+{
+ dev->ops = &usb_hub_ops;
+}
+
+struct chip_operations drivers_usb_hub_ops = {
+ CHIP_NAME("USB Hub")
+ .enable_dev = usb_hub_acpi_enable
+};
diff --git a/src/drivers/usb/hub/chip.h b/src/drivers/usb/hub/chip.h
new file mode 100644
index 0000000..d735f11
--- /dev/null
+++ b/src/drivers/usb/hub/chip.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __DRIVERS_USB_HUB_CHIP_H__
+#define __DRIVERS_USB_HUB_CHIP_H__
+
+struct drivers_usb_hub_config {
+ const char *name;
+ const char *desc;
+ unsigned int port_count; /* Number of Super-speed or High-speed ports */
+};
+
+#endif /* __DRIVERS_USB_HUB_CHIP_H__ */