acpi: Add support for a generic power sequence

Add a way for devices to enable and disable themselves using ACPI code
that updates GPIOs. This takes several timing parameters and supports
enable, reset and stop.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

1 files changed, 99 insertions, 0 deletions

diff --git a/lib/acpi/acpi_device.c b/lib/acpi/acpi_device.c
index b628fa1337..c66cafcfee 100644
--- a/lib/acpi/acpi_device.c
+++ b/lib/acpi/acpi_device.c
@@ -386,6 +386,105 @@ int acpi_device_write_interrupt_or_gpio(struct acpi_ctx *ctx,
 	return pin;
 }
 
+/* PowerResource() with Enable and/or Reset control */
+int acpi_device_add_power_res(struct acpi_ctx *ctx, u32 tx_state_val,
+			      const char *dw0_read, const char *dw0_write,
+			      const struct gpio_desc *reset_gpio,
+			      uint reset_delay_ms, uint reset_off_delay_ms,
+			      const struct gpio_desc *enable_gpio,
+			      uint enable_delay_ms, uint enable_off_delay_ms,
+			      const struct gpio_desc *stop_gpio,
+			      uint stop_delay_ms, uint stop_off_delay_ms)
+{
+	static const char *const power_res_dev_states[] = { "_PR0", "_PR3" };
+	struct acpi_gpio reset, enable, stop;
+	bool has_reset, has_enable, has_stop;
+	int ret;
+
+	gpio_get_acpi(reset_gpio, &reset);
+	gpio_get_acpi(enable_gpio, &enable);
+	gpio_get_acpi(stop_gpio, &stop);
+	has_reset = reset.pins[0];
+	has_enable = enable.pins[0];
+	has_stop = stop.pins[0];
+
+	if (!has_reset && !has_enable && !has_stop)
+		return -EINVAL;
+
+	/* PowerResource (PRIC, 0, 0) */
+	acpigen_write_power_res(ctx, "PRIC", 0, 0, power_res_dev_states,
+				ARRAY_SIZE(power_res_dev_states));
+
+	/* Method (_STA, 0, NotSerialized) { Return (0x1) } */
+	acpigen_write_sta(ctx, 0x1);
+
+	/* Method (_ON, 0, Serialized) */
+	acpigen_write_method_serialized(ctx, "_ON", 0);
+	if (reset_gpio) {
+		ret = acpigen_set_enable_tx_gpio(ctx, tx_state_val, dw0_read,
+						 dw0_write, &reset, true);
+		if (ret)
+			return log_msg_ret("reset1", ret);
+	}
+	if (has_enable) {
+		ret = acpigen_set_enable_tx_gpio(ctx, tx_state_val, dw0_read,
+						 dw0_write, &enable, true);
+		if (ret)
+			return log_msg_ret("enable1", ret);
+		if (enable_delay_ms)
+			acpigen_write_sleep(ctx, enable_delay_ms);
+	}
+	if (has_reset) {
+		ret = acpigen_set_enable_tx_gpio(ctx, tx_state_val, dw0_read,
+						 dw0_write, &reset, false);
+		if (ret)
+			return log_msg_ret("reset2", ret);
+		if (reset_delay_ms)
+			acpigen_write_sleep(ctx, reset_delay_ms);
+	}
+	if (has_stop) {
+		ret = acpigen_set_enable_tx_gpio(ctx, tx_state_val, dw0_read,
+						 dw0_write, &stop, false);
+		if (ret)
+			return log_msg_ret("stop1", ret);
+		if (stop_delay_ms)
+			acpigen_write_sleep(ctx, stop_delay_ms);
+	}
+	acpigen_pop_len(ctx);		/* _ON method */
+
+	/* Method (_OFF, 0, Serialized) */
+	acpigen_write_method_serialized(ctx, "_OFF", 0);
+	if (has_stop) {
+		ret = acpigen_set_enable_tx_gpio(ctx, tx_state_val, dw0_read,
+						 dw0_write, &stop, true);
+		if (ret)
+			return log_msg_ret("stop2", ret);
+		if (stop_off_delay_ms)
+			acpigen_write_sleep(ctx, stop_off_delay_ms);
+	}
+	if (has_reset) {
+		ret = acpigen_set_enable_tx_gpio(ctx, tx_state_val, dw0_read,
+						 dw0_write, &reset, true);
+		if (ret)
+			return log_msg_ret("reset3", ret);
+		if (reset_off_delay_ms)
+			acpigen_write_sleep(ctx, reset_off_delay_ms);
+	}
+	if (has_enable) {
+		ret = acpigen_set_enable_tx_gpio(ctx, tx_state_val, dw0_read,
+						 dw0_write, &enable, false);
+		if (ret)
+			return log_msg_ret("enable2", ret);
+		if (enable_off_delay_ms)
+			acpigen_write_sleep(ctx, enable_off_delay_ms);
+	}
+	acpigen_pop_len(ctx);		/* _OFF method */
+
+	acpigen_pop_len(ctx);		/* PowerResource PRIC */
+
+	return 0;
+}
+
 /* ACPI 6.3 section 6.4.3.8.2.1 - I2cSerialBus() */
 static void acpi_device_write_i2c(struct acpi_ctx *ctx,
 				  const struct acpi_i2c *i2c)