ASoC: cs-amp-lib: Add function to write calibration to UEFI

Add cs_amp_set_efi_calibration_data() to write an amp calibration
blob to UEFI calibration variable.

The UEFI variable will be updated or created as necessary.

- If a Vendor-specific variable exists it will be updated,
  else if the Cirrus variable exists it will be update
  else the Cirrus variable will be created.

Some collateral changes are required:

- cs_amp_convert_efi_status() now specifically handles
  EFI_WRITE_PROTECTED error.

- cs_amp_get_cal_efi_buffer() can optionally return the name,
  guid and attr of the variable it found.

- cs_amp_get_cal_efi_buffer() will update the 'size' field of
  the returned data blob if it is zero. The BIOS could have
  pre-allocated the UEFI variable as zero-filled

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20251021105022.1013685-9-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/sound/cs-amp-lib.h b/include/sound/cs-amp-lib.h
index 2e5616a5e1f7..240bc53a9307 100644
--- a/include/sound/cs-amp-lib.h
+++ b/include/sound/cs-amp-lib.h
@@ -55,6 +55,8 @@ int cs_amp_write_ambient_temp(struct cs_dsp *dsp,
 			      u32 temp);
 int cs_amp_get_efi_calibration_data(struct device *dev, u64 target_uid, int amp_index,
 				    struct cirrus_amp_cal_data *out_data);
+int cs_amp_set_efi_calibration_data(struct device *dev, int amp_index, int num_amps,
+				    const struct cirrus_amp_cal_data *in_data);
 int cs_amp_get_vendor_spkid(struct device *dev);
 struct dentry *cs_amp_create_debugfs(struct device *dev);