drivers/i2c/cs42l42: Add driver for generating device in SSDT

This driver uses the ACPI Device Property interface to generate
the required parameters into the _DSD table format expected by
the kernel

This was tested on the octopus/variants/fleex ainboard to ensure
that the SSDT contained the equivalent parameters that are provided
by the current DSDT object

Signed-off-by: Vitaly Rodionov <vitaly.rodionov@cirrus.corp-partner.google.com>
Change-Id: I7c3145b20a1ba743d91eb64b93cb001db3854c5d
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52395
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: EricR Lai <ericr_lai@compal.corp-partner.google.com>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/drivers/i2c/cs42l42/Kconfig

@@ -0,0 +1,3 @@
+config DRIVERS_I2C_CS42L42
+	bool
+	depends on HAVE_ACPI_TABLES

src/drivers/i2c/cs42l42/Makefile.inc

@@ -0,0 +1 @@
+ramstage-$(CONFIG_DRIVERS_I2C_CS42L42) += cs42l42.c

src/drivers/i2c/cs42l42/chip.h

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+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <acpi/acpi_device.h>
+
+enum cs42l42_ts_dbnc_rise {
+	RISE_DEB_0_MS = 0,
+	RISE_DEB_125_MS = 1,
+	RISE_DEB_250_MS = 2,
+	RISE_DEB_500_MS = 3,
+	RISE_DEB_750_MS = 4,
+	RISE_DEB_1000_MS = 5,
+	RISE_DEB_1250_MS = 6,
+	RISE_DEB_1500_MS = 7,
+};
+
+enum cs42l42_ts_dbnc_fall {
+	FALL_DEB_0_MS = 0,
+	FALL_DEB_125_MS = 1,
+	FALL_DEB_250_MS = 2,
+	FALL_DEB_500_MS = 3,
+	FALL_DEB_750_MS = 4,
+	FALL_DEB_1000_MS = 5,
+	FALL_DEB_1250_MS = 6,
+	FALL_DEB_1500_MS = 7,
+};
+
+enum cs42l42_hs_bias_ramp_rate {
+	HSBIAS_RAMP_FAST_RISE_SLOW_FALL = 0,
+	HSBIAS_RAMP_FAST = 1,
+	HSBIAS_RAMP_SLOW = 2,
+	HSBIAS_RAMP_SLOWEST = 3,
+};
+
+/*
+ * Cirrus Logic  CS42L42 Audio Codec devicetree bindings
+ * linux/Documentation/devicetree/bindings/sound/cs42l42.txt
+ */
+struct drivers_i2c_cs42l42_config {
+	/* Interrupt configuration */
+	struct acpi_irq irq;
+
+	/* Use GPIO based interrupt instead of PIRQ */
+	struct acpi_gpio irq_gpio;
+
+	/* Use GPIO based reset gpio */
+	struct acpi_gpio reset_gpio;
+
+	/* I2C Bus Frequency in Hertz (default 400kHz) */
+	unsigned int bus_speed;
+
+	/* Define cs42L42 parameters */
+	/*
+	 * cirrus,ts-inv : Boolean property. For jacks that invert the tip sense
+	 * polarity. Normal jacks will short tip sense pin to HS1 when headphones are
+	 * plugged in and leave tip sense floating when not plugged in. Inverting jacks
+	 * short tip sense when unplugged and float when plugged in.
+	 * false = Non-inverted
+	 * true  = Inverted
+	 * Default = Non-inverted
+	 */
+	bool ts_inv;
+	/*
+	 * cirrus,ts-dbnc-rise : Debounce the rising edge of TIP_SENSE_PLUG. With no
+	 * debounce, the tip sense pin might be noisy on a plug event.
+	 * Default = RISE_DEB_1000_MS
+	 */
+	enum cs42l42_ts_dbnc_rise ts_dbnc_rise;
+	/*
+	 * cirrus,ts-dbnc-fall : Debounce the falling edge of TIP_SENSE_UNPLUG.
+	 * With no debounce, the tip sense pin might be noisy on an unplug event.
+	 * Default = FALL_DEB_1000_MS
+	 */
+	enum cs42l42_ts_dbnc_fall ts_dbnc_fall;
+	/*
+	 * cirrus,btn-det-init-dbnce : This sets how long the driver sleeps after
+	 * enabling button detection interrupts. After auto-detection and before
+	 * servicing button interrupts, the HS bias needs time to settle. If you
+	 * don't wait, there is possibility for erroneous button interrupt.
+	 * Value in ms, 0 - 200.
+	 * Default = 100ms
+	 */
+	unsigned int btn_det_init_dbnce;
+	/*
+	 * cirrus,btn-det-event-dbnce : This sets how long the driver delays after
+	 * receiving a button press interrupt. With level detect interrupts, you want
+	 * to wait a small amount of time to make sure the button press is making a
+	 * clean connection with the bias resistors.
+	 * Value in ms, 0 - 20.
+	 * Default = 10ms
+	 */
+	unsigned int btn_det_event_dbnce;
+	/*
+	 * cirrus,bias-lvls : For a level-detect headset button scheme, each button
+	 * will bias the mic pin to a certain voltage. To determine which button was
+	 * pressed, the driver will compare this biased voltage to sequential,
+	 * decreasing voltages and will stop when a comparator is tripped,
+	 * indicating a comparator voltage < bias voltage. This value represents a
+	 * percentage of the internally generated HS bias voltage. For different
+	 * hardware setups, a designer might want to tweak this. This is an array of
+	 * descending values for the comparator voltage.
+	 * Array of 4 values
+	 * Each 0-63
+	 * < x1 x2 x3 x4 >
+	 * Default = < 15 8 4 1>
+	 */
+	uint64_t bias_lvls[4];
+	/* headset bias ramp rate */
+	enum cs42l42_hs_bias_ramp_rate hs_bias_ramp_rate;
+};

src/drivers/i2c/cs42l42/cs42l42.c

@@ -0,0 +1,122 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <acpi/acpi.h>
+#include <acpi/acpi_device.h>
+#include <acpi/acpigen.h>
+#include <console/console.h>
+#include <device/i2c_simple.h>
+#include <device/device.h>
+#include <device/path.h>
+
+#include "chip.h"
+
+#define CS42L42_ACPI_NAME	"CRUS"
+#define CS42L42_ACPI_HID	"10134242"
+
+static void cs42l42_fill_ssdt(const struct device *dev)
+{
+	struct drivers_i2c_cs42l42_config *config = dev->chip_info;
+	const char *scope = acpi_device_scope(dev);
+	const char *path = acpi_device_path(dev);
+	struct acpi_i2c i2c = {
+		.address = dev->path.i2c.device,
+		.mode_10bit = dev->path.i2c.mode_10bit,
+		.speed = config->bus_speed ? : I2C_SPEED_FAST,
+		.resource = scope,
+	};
+	struct acpi_dp *dsd;
+	int gpio_index = 0;
+
+	if (!scope)
+		return;
+
+	/* Device */
+	acpigen_write_scope(scope);
+	acpigen_write_device(acpi_device_name(dev));
+	acpigen_write_name_string("_HID", CS42L42_ACPI_HID);
+	acpigen_write_name_integer("_UID", 0);
+	acpigen_write_name_string("_DDN", dev->chip_ops->name);
+	acpigen_write_STA(acpi_device_status(dev));
+
+	/* Resources */
+	acpigen_write_name("_CRS");
+	acpigen_write_resourcetemplate_header();
+	acpi_device_write_i2c(&i2c);
+	/* Use either Interrupt() or GpioInt() */
+	if (config->irq_gpio.pin_count)
+		acpi_device_write_gpio(&config->irq_gpio);
+	else
+		acpi_device_write_interrupt(&config->irq);
+
+	/* for cs42l42reset gpio */
+	if (config->reset_gpio.pin_count)
+		acpi_device_write_gpio(&config->reset_gpio);
+
+	acpigen_write_resourcetemplate_footer();
+
+	/* AAD Child Device Properties */
+	dsd = acpi_dp_new_table("_DSD");
+	if (config->irq_gpio.pin_count)
+		acpi_dp_add_gpio(dsd, "irq-gpios", path,
+			 gpio_index++,  /* Index = 0 */
+			 0,  /* Pin = 0 (There is a single pin in the GPIO resource). */
+			 config->irq_gpio.active_low);
+	if (config->reset_gpio.pin_count)
+		acpi_dp_add_gpio(dsd, "reset-gpios", path,
+			 gpio_index++,  /* Index = 0 or 1 (if irq gpio is written). */
+			 0,  /* Pin = 0 (There is a single pin in the GPIO resource). */
+			 config->reset_gpio.active_low);
+	acpi_dp_add_integer(dsd, "cirrus,ts-inv", config->ts_inv ? 1 : 0);
+	acpi_dp_add_integer(dsd, "cirrus,ts-dbnc-rise", config->ts_dbnc_rise);
+	acpi_dp_add_integer(dsd, "cirrus,ts-dbnc-fall", config->ts_dbnc_fall);
+	acpi_dp_add_integer(dsd, "cirrus,btn-det-init-dbnce", config->btn_det_init_dbnce);
+
+	if (config->btn_det_init_dbnce > 200) {
+		printk(BIOS_ERR, "%s: Incorrect btn_det_init_dbnce(%d). Using default of 100ms\n",
+				__func__, config->btn_det_init_dbnce);
+		config->btn_det_init_dbnce = 100;
+	}
+
+	acpi_dp_add_integer(dsd, "cirrus,btn-det-event-dbnce", config->btn_det_event_dbnce);
+
+	if (config->btn_det_event_dbnce > 100) {
+		printk(BIOS_ERR, "%s: Incorrect btn_det_event_dbnce(%d). Using default of 10ms\n",
+				__func__, config->btn_det_event_dbnce);
+		config->btn_det_event_dbnce = 10;
+	}
+
+	acpi_dp_add_integer_array(dsd, "cirrus,bias-lvls", config->bias_lvls, 4);
+	acpi_dp_add_integer(dsd, "cirrus,hs-bias-ramp-rate", config->hs_bias_ramp_rate);
+
+	/* Write Device Property Hierarchy */
+	acpi_dp_write(dsd);
+
+	acpigen_pop_len(); /* Device */
+	acpigen_pop_len(); /* Scope */
+
+	printk(BIOS_INFO, "%s: %s address 0%xh irq %d\n",
+	       acpi_device_path(dev), dev->chip_ops->name,
+	       dev->path.i2c.device, config->irq.pin);
+}
+
+static const char *cs42l42_acpi_name(const struct device *dev)
+{
+	return CS42L42_ACPI_NAME;
+}
+
+static struct device_operations cs42l42_ops = {
+	.read_resources		= noop_read_resources,
+	.set_resources		= noop_set_resources,
+	.acpi_name		= cs42l42_acpi_name,
+	.acpi_fill_ssdt		= cs42l42_fill_ssdt,
+};
+
+static void cs42l42_enable(struct device *dev)
+{
+	dev->ops = &cs42l42_ops;
+}
+
+struct chip_operations drivers_i2c_cs42l42_ops = {
+	CHIP_NAME("Cirrus Logic CS42l42 Audio Codec")
+	.enable_dev = cs42l42_enable
+};