[PATCH v3 13/17] ALSA: hda: cs35l41: Read Speaker Calibration data from UEFI variables

[Vitaly Rodionov <vitalyr@opensource.cirrus.com>]

From: Stefan Binding <sbinding@opensource.cirrus.com>

Speaker Calibration data, specific to an individual speaker is
stored inside UEFI variables during calibration, and can be
used by the DSP.

Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
Signed-off-by: Vitaly Rodionov <vitalyr@opensource.cirrus.com>
---

Changes since v2:
 - Fixed building without CONFIG_EFI
 
 sound/pci/hda/cs35l41_hda.c | 63 +++++++++++++++++++++++++++++++++++++
 sound/pci/hda/cs35l41_hda.h | 15 +++++++++
 2 files changed, 78 insertions(+)

diff --git a/sound/pci/hda/cs35l41_hda.c b/sound/pci/hda/cs35l41_hda.c
index 9c622104bf01..016f97f61c34 100644
--- a/sound/pci/hda/cs35l41_hda.c
+++ b/sound/pci/hda/cs35l41_hda.c
@@ -26,6 +26,9 @@
 #define HALO_STATE_DSP_CTL_NAME		"HALO_STATE"
 #define HALO_STATE_DSP_CTL_TYPE		5
 #define HALO_STATE_DSP_CTL_ALG		262308
+#define CAL_R_DSP_CTL_NAME		"CAL_R"
+#define CAL_R_DSP_CTL_TYPE		5
+#define CAL_R_DSP_CTL_ALG		205
 
 static const struct reg_sequence cs35l41_hda_config[] = {
 	{ CS35L41_PLL_CLK_CTRL,		0x00000430 }, // 3072000Hz, BCLK Input, PLL_REFCLK_EN = 1
@@ -282,6 +285,61 @@ static int cs35l41_request_firmware_files(struct cs35l41_hda *cs35l41,
 	return ret;
 }
 
+#if IS_ENABLED(CONFIG_EFI)
+static int cs35l41_apply_calibration(struct cs35l41_hda *cs35l41)
+{
+	static efi_guid_t efi_guid = EFI_GUID(0x02f9af02, 0x7734, 0x4233, 0xb4, 0x3d, 0x93, 0xfe,
+					      0x5a, 0xa3, 0x5d, 0xb3);
+	static efi_char16_t efi_name[] = L"CirrusSmartAmpCalibrationData";
+	const struct cs35l41_amp_efi_data *efi_data;
+	const struct cs35l41_amp_cal_data *cl;
+	unsigned long data_size = 0;
+	efi_status_t status;
+	int ret = 0;
+	u8 *data = NULL;
+	u32 attr;
+	u32 r0;
+
+	/* Get real size of UEFI variable */
+	status = efi.get_variable(efi_name, &efi_guid, &attr, &data_size, data);
+	if (status == EFI_BUFFER_TOO_SMALL) {
+		ret = -ENODEV;
+		/* Allocate data buffer of data_size bytes */
+		data = vmalloc(data_size);
+		if (!data)
+			return -ENOMEM;
+		/* Get variable contents into buffer */
+		status = efi.get_variable(efi_name, &efi_guid, &attr, &data_size, data);
+		if (status == EFI_SUCCESS) {
+			efi_data = (struct cs35l41_amp_efi_data *)data;
+			dev_dbg(cs35l41->dev, "Calibration: Size=%d, Amp Count=%d\n",
+				efi_data->size, efi_data->count);
+			if (efi_data->count > cs35l41->index) {
+				cl = &efi_data->data[cs35l41->index];
+				dev_dbg(cs35l41->dev,
+					"Calibration: Ambient=%02x, Status=%02x, R0=%d\n",
+					cl->calAmbient, cl->calStatus, cl->calR);
+				r0 = cpu_to_be32(cl->calR);
+				ret = hda_cs_dsp_write_ctl(&cs35l41->cs_dsp, CAL_R_DSP_CTL_NAME,
+							   CAL_R_DSP_CTL_TYPE, CAL_R_DSP_CTL_ALG,
+							   &r0, 4);
+				if (ret)
+					dev_err(cs35l41->dev, "Cannot Write Control: %s - %d\n",
+						CAL_R_DSP_CTL_NAME, ret);
+			}
+		}
+		vfree(data);
+	}
+	return ret;
+}
+#else
+static int cs35l41_apply_calibration(struct cs35l41_hda *cs35l41)
+{
+	dev_warn(cs35l41->dev, "Calibration not supported without EFI support.\n");
+	return 0;
+}
+#endif
+
 static int cs35l41_init_dsp(struct cs35l41_hda *cs35l41)
 {
 	const struct firmware *coeff_firmware = NULL;
@@ -314,7 +372,12 @@ static int cs35l41_init_dsp(struct cs35l41_hda *cs35l41)
 
 	ret = cs_dsp_power_up(dsp, wmfw_firmware, wmfw_filename, coeff_firmware, coeff_filename,
 			      FW_NAME);
+	if (ret)
+		goto err_release;
+
+	ret = cs35l41_apply_calibration(cs35l41);
 
+err_release:
 	if (wmfw_firmware)
 		release_firmware(wmfw_firmware);
 	if (coeff_firmware)
diff --git a/sound/pci/hda/cs35l41_hda.h b/sound/pci/hda/cs35l41_hda.h
index 54521a013e78..3cf9871fbed2 100644
--- a/sound/pci/hda/cs35l41_hda.h
+++ b/sound/pci/hda/cs35l41_hda.h
@@ -10,6 +10,7 @@
 #ifndef __CS35L41_HDA_H__
 #define __CS35L41_HDA_H__
 
+#include <linux/efi.h>
 #include <linux/regulator/consumer.h>
 #include <linux/gpio/consumer.h>
 #include <linux/device.h>
@@ -18,6 +19,20 @@
 #include <linux/firmware/cirrus/cs_dsp.h>
 #include <linux/firmware/cirrus/wmfw.h>
 
+struct cs35l41_amp_cal_data {
+	u32 calTarget[2];
+	u32 calTime[2];
+	s8 calAmbient;
+	u8 calStatus;
+	u16 calR;
+} __packed;
+
+struct cs35l41_amp_efi_data {
+	u32 size;
+	u32 count;
+	struct cs35l41_amp_cal_data data[];
+} __packed;
+
 enum cs35l41_hda_spk_pos {
 	CS35l41_LEFT,
 	CS35l41_RIGHT,
-- 
2.34.1