ALSA: hda: hda_cs_dsp_ctl: Add Library to support CS_DSP ALSA controls

The cs35l41 part contains a DSP which is able to run firmware.
The cs_dsp library can be used to control the DSP.
These controls can be exposed to userspace using ALSA controls.
This library adds apis to be able to interface between
cs_dsp and hda drivers and expose the relevant controls as
ALSA controls.

[ Note: the dependency of CONFIG_SND_HDA_CS_DSP_CONTROLS Kconfig is
  corrected.  Also, this Kconfig isn't enabled now but will be
  actually enabled in a later patch -- tiwai ]

Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
Signed-off-by: Vitaly Rodionov <vitalyr@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20220630002335.366545-2-vitalyr@opensource.cirrus.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

MAINTAINERS

@@ -4755,6 +4755,7 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/sound/cirrus,cs*
 F:	include/dt-bindings/sound/cs*
 F:	sound/pci/hda/cs*
+F:	sound/pci/hda/hda_cs_dsp_ctl.*
 F:	sound/soc/codecs/cs*
 
 CIRRUS LOGIC DSP FIRMWARE DRIVER

sound/pci/hda/Kconfig

@@ -96,6 +96,10 @@ config SND_HDA_SCODEC_CS35L41
 	select SND_HDA_GENERIC
 	select REGMAP_IRQ
 
+config SND_HDA_CS_DSP_CONTROLS
+	tristate
+	select CS_DSP
+
 config SND_HDA_SCODEC_CS35L41_I2C
 	tristate "Build CS35L41 HD-audio side codec support for I2C Bus"
 	depends on I2C

sound/pci/hda/Makefile

@@ -31,6 +31,7 @@ snd-hda-codec-hdmi-objs :=	patch_hdmi.o hda_eld.o
 snd-hda-scodec-cs35l41-objs :=		cs35l41_hda.o
 snd-hda-scodec-cs35l41-i2c-objs :=	cs35l41_hda_i2c.o
 snd-hda-scodec-cs35l41-spi-objs :=	cs35l41_hda_spi.o
+snd-hda-cs-dsp-ctls-objs :=		hda_cs_dsp_ctl.o
 
 # common driver
 obj-$(CONFIG_SND_HDA) := snd-hda-codec.o
@@ -54,6 +55,7 @@ obj-$(CONFIG_SND_HDA_CODEC_HDMI) += snd-hda-codec-hdmi.o
 obj-$(CONFIG_SND_HDA_SCODEC_CS35L41) += snd-hda-scodec-cs35l41.o
 obj-$(CONFIG_SND_HDA_SCODEC_CS35L41_I2C) += snd-hda-scodec-cs35l41-i2c.o
 obj-$(CONFIG_SND_HDA_SCODEC_CS35L41_SPI) += snd-hda-scodec-cs35l41-spi.o
+obj-$(CONFIG_SND_HDA_CS_DSP_CONTROLS) += snd-hda-cs-dsp-ctls.o
 
 # this must be the last entry after codec drivers;
 # otherwise the codec patches won't be hooked before the PCI probe

sound/pci/hda/hda_cs_dsp_ctl.c

@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// HDA DSP ALSA Control Driver
+//
+// Copyright 2022 Cirrus Logic, Inc.
+//
+// Author: Stefan Binding <sbinding@opensource.cirrus.com>
+
+#include <linux/module.h>
+#include <sound/soc.h>
+#include <linux/firmware/cirrus/cs_dsp.h>
+#include <linux/firmware/cirrus/wmfw.h>
+#include "hda_cs_dsp_ctl.h"
+
+#define ADSP_MAX_STD_CTRL_SIZE               512
+
+struct hda_cs_dsp_coeff_ctl {
+	struct cs_dsp_coeff_ctl *cs_ctl;
+	struct snd_card *card;
+	struct snd_kcontrol *kctl;
+};
+
+static const char * const hda_cs_dsp_fw_text[HDA_CS_DSP_NUM_FW] = {
+	[HDA_CS_DSP_FW_SPK_PROT] = "Prot",
+	[HDA_CS_DSP_FW_SPK_CALI] = "Cali",
+	[HDA_CS_DSP_FW_SPK_DIAG] = "Diag",
+	[HDA_CS_DSP_FW_MISC] =     "Misc",
+};
+
+static int hda_cs_dsp_coeff_info(struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+	struct hda_cs_dsp_coeff_ctl *ctl = (struct hda_cs_dsp_coeff_ctl *)snd_kcontrol_chip(kctl);
+	struct cs_dsp_coeff_ctl *cs_ctl = ctl->cs_ctl;
+
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_BYTES;
+	uinfo->count = cs_ctl->len;
+
+	return 0;
+}
+
+static int hda_cs_dsp_coeff_put(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+	struct hda_cs_dsp_coeff_ctl *ctl = (struct hda_cs_dsp_coeff_ctl *)snd_kcontrol_chip(kctl);
+	struct cs_dsp_coeff_ctl *cs_ctl = ctl->cs_ctl;
+	char *p = ucontrol->value.bytes.data;
+	int ret = 0;
+
+	mutex_lock(&cs_ctl->dsp->pwr_lock);
+	ret = cs_dsp_coeff_write_ctrl(cs_ctl, 0, p, cs_ctl->len);
+	mutex_unlock(&cs_ctl->dsp->pwr_lock);
+
+	return ret;
+}
+
+static int hda_cs_dsp_coeff_get(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *ucontrol)
+{
+	struct hda_cs_dsp_coeff_ctl *ctl = (struct hda_cs_dsp_coeff_ctl *)snd_kcontrol_chip(kctl);
+	struct cs_dsp_coeff_ctl *cs_ctl = ctl->cs_ctl;
+	char *p = ucontrol->value.bytes.data;
+	int ret;
+
+	mutex_lock(&cs_ctl->dsp->pwr_lock);
+	ret = cs_dsp_coeff_read_ctrl(cs_ctl, 0, p, cs_ctl->len);
+	mutex_unlock(&cs_ctl->dsp->pwr_lock);
+
+	return ret;
+}
+
+static unsigned int wmfw_convert_flags(unsigned int in)
+{
+	unsigned int out, rd, wr, vol;
+
+	rd = SNDRV_CTL_ELEM_ACCESS_READ;
+	wr = SNDRV_CTL_ELEM_ACCESS_WRITE;
+	vol = SNDRV_CTL_ELEM_ACCESS_VOLATILE;
+
+	out = 0;
+
+	if (in) {
+		out |= rd;
+		if (in & WMFW_CTL_FLAG_WRITEABLE)
+			out |= wr;
+		if (in & WMFW_CTL_FLAG_VOLATILE)
+			out |= vol;
+	} else {
+		out |= rd | wr | vol;
+	}
+
+	return out;
+}
+
+static int hda_cs_dsp_add_kcontrol(struct hda_cs_dsp_coeff_ctl *ctl, const char *name)
+{
+	struct cs_dsp_coeff_ctl *cs_ctl = ctl->cs_ctl;
+	struct snd_kcontrol_new kcontrol = {0};
+	struct snd_kcontrol *kctl;
+	int ret = 0;
+
+	if (cs_ctl->len > ADSP_MAX_STD_CTRL_SIZE) {
+		dev_err(cs_ctl->dsp->dev, "KControl %s: length %zu exceeds maximum %d\n", name,
+			cs_ctl->len, ADSP_MAX_STD_CTRL_SIZE);
+		return -EINVAL;
+	}
+
+	kcontrol.name = name;
+	kcontrol.info = hda_cs_dsp_coeff_info;
+	kcontrol.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
+	kcontrol.access = wmfw_convert_flags(cs_ctl->flags);
+	kcontrol.get = hda_cs_dsp_coeff_get;
+	kcontrol.put = hda_cs_dsp_coeff_put;
+
+	/* Save ctl inside private_data, ctl is owned by cs_dsp,
+	 * and will be freed when cs_dsp removes the control */
+	kctl = snd_ctl_new1(&kcontrol, (void *)ctl);
+	if (!kctl) {
+		ret = -ENOMEM;
+		return ret;
+	}
+
+	ret = snd_ctl_add(ctl->card, kctl);
+	if (ret) {
+		dev_err(cs_ctl->dsp->dev, "Failed to add KControl %s = %d\n", kcontrol.name, ret);
+		return ret;
+	}
+
+	dev_dbg(cs_ctl->dsp->dev, "Added KControl: %s\n", kcontrol.name);
+	ctl->kctl = kctl;
+
+	return 0;
+}
+
+int hda_cs_dsp_control_add(struct cs_dsp_coeff_ctl *cs_ctl, struct hda_cs_dsp_ctl_info *info)
+{
+	struct cs_dsp *cs_dsp = cs_ctl->dsp;
+	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
+	struct hda_cs_dsp_coeff_ctl *ctl;
+	const char *region_name;
+	int ret;
+
+	if (cs_ctl->flags & WMFW_CTL_FLAG_SYS)
+		return 0;
+
+	region_name = cs_dsp_mem_region_name(cs_ctl->alg_region.type);
+	if (!region_name) {
+		dev_err(cs_dsp->dev, "Unknown region type: %d\n", cs_ctl->alg_region.type);
+		return -EINVAL;
+	}
+
+	ret = scnprintf(name, SNDRV_CTL_ELEM_ID_NAME_MAXLEN, "%s %s %.12s %x", info->device_name,
+			cs_dsp->name, hda_cs_dsp_fw_text[info->fw_type], cs_ctl->alg_region.alg);
+
+	if (cs_ctl->subname) {
+		int avail = SNDRV_CTL_ELEM_ID_NAME_MAXLEN - ret - 2;
+		int skip = 0;
+
+		/* Truncate the subname from the start if it is too long */
+		if (cs_ctl->subname_len > avail)
+			skip = cs_ctl->subname_len - avail;
+
+		snprintf(name + ret, SNDRV_CTL_ELEM_ID_NAME_MAXLEN - ret,
+			 " %.*s", cs_ctl->subname_len - skip, cs_ctl->subname + skip);
+	}
+
+	ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
+	if (!ctl)
+		return -ENOMEM;
+
+	ctl->cs_ctl = cs_ctl;
+	ctl->card = info->card;
+	cs_ctl->priv = ctl;
+
+	ret = hda_cs_dsp_add_kcontrol(ctl, name);
+	if (ret) {
+		dev_err(cs_dsp->dev, "Error (%d) adding control %s\n", ret, name);
+		kfree(ctl);
+		return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(hda_cs_dsp_control_add, SND_HDA_CS_DSP_CONTROLS);
+
+void hda_cs_dsp_control_remove(struct cs_dsp_coeff_ctl *cs_ctl)
+{
+	struct hda_cs_dsp_coeff_ctl *ctl = cs_ctl->priv;
+
+	kfree(ctl);
+}
+EXPORT_SYMBOL_NS_GPL(hda_cs_dsp_control_remove, SND_HDA_CS_DSP_CONTROLS);
+
+MODULE_DESCRIPTION("CS_DSP ALSA Control HDA Library");
+MODULE_AUTHOR("Stefan Binding, <sbinding@opensource.cirrus.com>");
+MODULE_LICENSE("GPL");

sound/pci/hda/hda_cs_dsp_ctl.h

@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * HDA DSP ALSA Control Driver
+ *
+ * Copyright 2022 Cirrus Logic, Inc.
+ *
+ * Author: Stefan Binding <sbinding@opensource.cirrus.com>
+ */
+
+#ifndef __HDA_CS_DSP_CTL_H__
+#define __HDA_CS_DSP_CTL_H__
+
+#include <sound/soc.h>
+#include <linux/firmware/cirrus/cs_dsp.h>
+
+enum hda_cs_dsp_fw_id {
+	HDA_CS_DSP_FW_SPK_PROT,
+	HDA_CS_DSP_FW_SPK_CALI,
+	HDA_CS_DSP_FW_SPK_DIAG,
+	HDA_CS_DSP_FW_MISC,
+	HDA_CS_DSP_NUM_FW
+};
+
+struct hda_cs_dsp_ctl_info {
+	struct snd_card *card;
+	enum hda_cs_dsp_fw_id fw_type;
+	const char *device_name;
+};
+
+int hda_cs_dsp_control_add(struct cs_dsp_coeff_ctl *cs_ctl, struct hda_cs_dsp_ctl_info *info);
+void hda_cs_dsp_control_remove(struct cs_dsp_coeff_ctl *cs_ctl);
+
+#endif /*__HDA_CS_DSP_CTL_H__*/