Add stub for tas5825m driver and add it to oryp6 model

src/drivers/i2c/tas5825m/Kconfig

@@ -0,0 +1,5 @@
+config DRIVERS_I2C_TAS5825M
+	bool
+	default n
+	help
+	  Enable support for TI TAS5825M Amplifier.

src/drivers/i2c/tas5825m/Makefile.inc

@@ -0,0 +1 @@
+ramstage-$(CONFIG_DRIVERS_I2C_TAS5825M) += tas5825m.c

src/drivers/i2c/tas5825m/chip.h

@@ -0,0 +1,5 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+struct drivers_i2c_tas5825m_config {
+	//TODO
+};

src/drivers/i2c/tas5825m/tas5825m.c

@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <console/console.h>
+#include <delay.h>
+#include <device/device.h>
+#include <device/smbus.h>
+#include <device/pci.h>
+#include "chip.h"
+
+static int tas5825m_setup(struct device *dev) {
+	struct drivers_i2c_tas5825m_config *config = dev->chip_info;
+
+	if (!config) {
+		printk(BIOS_ERR, "tas5825m: failed to find config\n");
+		return -1;
+	}
+
+	//TODO: handle errors
+	int res;
+	#define R(F, E) { \
+		res = F; \
+		if (res < 0) { \
+			printk(BIOS_ERR, "tas5825m: %s\n", E); \
+			return res; \
+		} \
+	}
+
+	// Set page to 0
+	R(smbus_write_byte(dev, 0x00, 0x00), "failed to set page");
+
+	// Set book to 0
+	R(smbus_write_byte(dev, 0x7F, 0x00), "failed to set book");
+
+	// Get DIE_ID
+	R(smbus_read_byte(dev, 0x67), "failed to read die id");
+	printk(BIOS_DEBUG, "tas5825m: DIE_ID=%02X\n", res);
+
+	#undef R
+	return 0;
+}
+
+static void tas5825m_init(struct device *dev) {
+	if (dev->enabled && dev->path.type == DEVICE_PATH_I2C &&
+		ops_smbus_bus(get_pbus_smbus(dev))) {
+		printk(BIOS_DEBUG, "tas5825m at %s\n", dev_path(dev));
+		int res = tas5825m_setup(dev);
+		if (res) {
+			printk(BIOS_ERR, "tas5825m init failed: %d\n", res);
+		} else {
+			printk(BIOS_DEBUG, "tas5825m init successful\n");
+		}
+	}
+}
+
+static struct device_operations tas5825m_operations = {
+	.read_resources		= noop_read_resources,
+	.set_resources		= noop_set_resources,
+	.init			= tas5825m_init,
+};
+
+static void tas5825m_enable_dev(struct device *dev) {
+	dev->ops = &tas5825m_operations;
+}
+
+struct chip_operations drivers_i2c_tas5825m_ops = {
+	CHIP_NAME("TI TAS5825M Amplifier")
+	.enable_dev = tas5825m_enable_dev,
+};

src/mainboard/system76/oryp6/Kconfig

@@ -4,6 +4,7 @@ config BOARD_SPECIFIC_OPTIONS
 	def_bool y
 	select BOARD_ROMSIZE_KB_16384
 	select DRIVERS_I2C_HID
+	select DRIVERS_I2C_TAS5825M
 	select DRIVERS_SYSTEM76_EC
 	select EC_ACPI
 	select HAVE_ACPI_RESUME

src/mainboard/system76/oryp6/devicetree.cb

@@ -322,7 +322,11 @@ chip soc/intel/cannonlake
 		device pci 1f.1 off end # P2SB
 		device pci 1f.2 off end # Power Management Controller
 		device pci 1f.3 on  end # Intel HDA
-		device pci 1f.4 on  end # SMBus
+		device pci 1f.4 on
+			chip drivers/i2c/tas5825m
+				device i2c 4e on end # (8bit address: 0x9c)
+			end # tas5825m
+		end # SMBus
 		device pci 1f.5 on  end # PCH SPI
 		device pci 1f.6 off end # GbE
 	end