acpi: Support generating a multi-function _DSM for devices
Add a function to generate ACPI code for a _DSM method for a device.
This includes functions for starting and ending each part of the _DSM.
Signed-off-by: Simon Glass <sjg@chromium.org>
[bmeng: fix the "new blank line at EOF" git warning]
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/lib/acpi/acpi_device.c b/lib/acpi/acpi_device.c
index 3c75b6d..8248664 100644
--- a/lib/acpi/acpi_device.c
+++ b/lib/acpi/acpi_device.c
@@ -487,6 +487,49 @@
return 0;
}
+int acpi_device_write_dsm_i2c_hid(struct acpi_ctx *ctx,
+ int hid_desc_reg_offset)
+{
+ int ret;
+
+ acpigen_write_dsm_start(ctx);
+ ret = acpigen_write_dsm_uuid_start(ctx, ACPI_DSM_I2C_HID_UUID);
+ if (ret)
+ return log_ret(ret);
+
+ acpigen_write_dsm_uuid_start_cond(ctx, 0);
+ /* ToInteger (Arg1, Local2) */
+ acpigen_write_to_integer(ctx, ARG1_OP, LOCAL2_OP);
+ /* If (LEqual (Local2, 0x0)) */
+ acpigen_write_if_lequal_op_int(ctx, LOCAL2_OP, 0x0);
+ /* Return (Buffer (One) { 0x1f }) */
+ acpigen_write_return_singleton_buffer(ctx, 0x1f);
+ acpigen_pop_len(ctx); /* Pop : If */
+ /* Else */
+ acpigen_write_else(ctx);
+ /* If (LEqual (Local2, 0x1)) */
+ acpigen_write_if_lequal_op_int(ctx, LOCAL2_OP, 0x1);
+ /* Return (Buffer (One) { 0x3f }) */
+ acpigen_write_return_singleton_buffer(ctx, 0x3f);
+ acpigen_pop_len(ctx); /* Pop : If */
+ /* Else */
+ acpigen_write_else(ctx);
+ /* Return (Buffer (One) { 0x0 }) */
+ acpigen_write_return_singleton_buffer(ctx, 0x0);
+ acpigen_pop_len(ctx); /* Pop : Else */
+ acpigen_pop_len(ctx); /* Pop : Else */
+ acpigen_write_dsm_uuid_end_cond(ctx);
+
+ acpigen_write_dsm_uuid_start_cond(ctx, 1);
+ acpigen_write_return_byte(ctx, hid_desc_reg_offset);
+ acpigen_write_dsm_uuid_end_cond(ctx);
+
+ acpigen_write_dsm_uuid_end(ctx);
+ acpigen_write_dsm_end(ctx);
+
+ 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)