[PATCH 6/6] ASoC: SDCA: Add support for GE Entity properties

[Charles Keepax <ckeepax@opensource.cirrus.com>]

Add support for parsing the Group Entity properties from DisCo/ACPI.
Group Entities allow control of several other Entities, typically
Selector Units, from a single control.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---
 include/sound/sdca_function.h   |  48 ++++++++++++
 sound/soc/sdca/sdca_functions.c | 129 ++++++++++++++++++++++++++++++++
 2 files changed, 177 insertions(+)

diff --git a/include/sound/sdca_function.h b/include/sound/sdca_function.h
index d7489e3c7e471..253654568a41e 100644
--- a/include/sound/sdca_function.h
+++ b/include/sound/sdca_function.h
@@ -44,6 +44,11 @@ struct sdca_function_desc;
  */
 #define SDCA_MAX_DELAY_COUNT 256
 
+/*
+ * Sanity check on size of affected controls data, can be expanded if needed.
+ */
+#define SDCA_MAX_AFFECTED_COUNT 2048
+
 /**
  * enum sdca_function_type - SDCA Function Type codes
  * @SDCA_FUNCTION_TYPE_SMART_AMP: Amplifier with protection features.
@@ -927,11 +932,51 @@ enum sdca_entity_type {
 	SDCA_ENTITY_TYPE_HIDE				= 0x31,
 };
 
+/**
+ * struct sdca_ge_control - control entry in the affected controls list
+ * @id: Entity ID of the Control affected.
+ * @sel: Control Selector of the Control affected.
+ * @cn: Control Number of the Control affected.
+ * @val: Value written to Control for this Mode.
+ */
+struct sdca_ge_control {
+	int id;
+	int sel;
+	int cn;
+	int val;
+};
+
+/**
+ * struct sdca_ge_mode - mode entry in the affected controls list
+ * @controls: Dynamically allocated array of controls written for this Mode.
+ * @num_controls: Number of controls written in this Mode.
+ * @val: GE Selector Mode value.
+ */
+struct sdca_ge_mode {
+	struct sdca_ge_control *controls;
+	int num_controls;
+	int val;
+};
+
+/**
+ * struct sdca_entity_ge - information specific to Group Entities
+ * @kctl: ALSA control pointer that can be used by linked Entities.
+ * @modes: Dynamically allocated array of Modes and the Controls written
+ * in each mode.
+ * @num_modes: Number of Modes.
+ */
+struct sdca_entity_ge {
+	struct snd_kcontrol_new *kctl;
+	struct sdca_ge_mode *modes;
+	int num_modes;
+};
+
 /**
  * struct sdca_entity - information for one SDCA Entity
  * @label: String such as "OT 12".
  * @id: Identifier used for addressing.
  * @type: Type code for the Entity.
+ * @group: Pointer to Group Entity controlling this one, NULL if N/A.
  * @sources: Dynamically allocated array pointing to each input Entity
  * connected to this Entity.
  * @controls: Dynamically allocated array of Controls.
@@ -940,12 +985,14 @@ enum sdca_entity_type {
  * @iot: Input/Output Terminal specific Entity properties.
  * @cs: Clock Source specific Entity properties.
  * @pde: Power Domain Entity specific Entity properties.
+ * @ge: Group Entity specific Entity properties.
  */
 struct sdca_entity {
 	const char *label;
 	int id;
 	enum sdca_entity_type type;
 
+	struct sdca_entity *group;
 	struct sdca_entity **sources;
 	struct sdca_control *controls;
 	int num_sources;
@@ -954,6 +1001,7 @@ struct sdca_entity {
 		struct sdca_entity_iot iot;
 		struct sdca_entity_cs cs;
 		struct sdca_entity_pde pde;
+		struct sdca_entity_ge ge;
 	};
 };
 
diff --git a/sound/soc/sdca/sdca_functions.c b/sound/soc/sdca/sdca_functions.c
index 0cc25fb9679b4..c8efdc5301b53 100644
--- a/sound/soc/sdca/sdca_functions.c
+++ b/sound/soc/sdca/sdca_functions.c
@@ -1136,6 +1136,92 @@ static int find_sdca_entity_pde(struct device *dev,
 	return 0;
 }
 
+struct raw_ge_mode {
+	u8 val;
+	u8 num_controls;
+	struct {
+		u8 id;
+		u8 sel;
+		u8 cn;
+		__le32 val;
+	} __packed controls[] __counted_by(num_controls);
+} __packed;
+
+static int find_sdca_entity_ge(struct device *dev,
+			       struct fwnode_handle *entity_node,
+			       struct sdca_entity *entity)
+{
+	struct sdca_entity_ge *group = &entity->ge;
+	u8 *affected_list __free(kfree) = NULL;
+	u8 *affected_iter;
+	int num_affected;
+	int i, j;
+
+	num_affected = fwnode_property_count_u8(entity_node,
+						"mipi-sdca-ge-selectedmode-controls-affected");
+	if (!num_affected || num_affected == -EINVAL) {
+		return 0;
+	} else if (num_affected < 0) {
+		dev_err(dev, "%s: failed to read affected controls: %d\n",
+			entity->label, num_affected);
+		return num_affected;
+	} else if (num_affected > SDCA_MAX_AFFECTED_COUNT) {
+		dev_err(dev, "%s: maximum affected controls size exceeded\n",
+			entity->label);
+		return -EINVAL;
+	}
+
+	affected_list = kcalloc(num_affected, sizeof(*affected_list), GFP_KERNEL);
+	if (!affected_list)
+		return -ENOMEM;
+
+	fwnode_property_read_u8_array(entity_node,
+				      "mipi-sdca-ge-selectedmode-controls-affected",
+				      affected_list, num_affected);
+
+	group->num_modes = *affected_list;
+	affected_iter = affected_list + 1;
+
+	group->modes = devm_kcalloc(dev, group->num_modes, sizeof(*group->modes),
+				    GFP_KERNEL);
+	if (!group->modes)
+		return -ENOMEM;
+
+	for (i = 0; i < group->num_modes; i++) {
+		struct raw_ge_mode *raw = (struct raw_ge_mode *)affected_iter;
+		struct sdca_ge_mode *mode = &group->modes[i];
+
+		affected_iter += sizeof(*raw);
+		if (affected_iter > affected_list + num_affected)
+			goto bad_list;
+
+		mode->val = raw->val;
+		mode->num_controls = raw->num_controls;
+
+		affected_iter += mode->num_controls * sizeof(raw->controls[0]);
+		if (affected_iter > affected_list + num_affected)
+			goto bad_list;
+
+		mode->controls = devm_kcalloc(dev, mode->num_controls,
+					      sizeof(*mode->controls), GFP_KERNEL);
+		if (!mode->controls)
+			return -ENOMEM;
+
+		for (j = 0; j < mode->num_controls; j++) {
+			mode->controls[j].id = raw->controls[j].id;
+			mode->controls[j].sel = raw->controls[j].sel;
+			mode->controls[j].cn = raw->controls[j].cn;
+			mode->controls[j].val = le32_to_cpu(raw->controls[j].val);
+		}
+	}
+
+	return 0;
+
+bad_list:
+	dev_err(dev, "%s: malformed affected controls list\n", entity->label);
+	return -EINVAL;
+}
+
 static int find_sdca_entity(struct device *dev,
 			    struct fwnode_handle *function_node,
 			    struct fwnode_handle *entity_node,
@@ -1174,6 +1260,9 @@ static int find_sdca_entity(struct device *dev,
 	case SDCA_ENTITY_TYPE_PDE:
 		ret = find_sdca_entity_pde(dev, entity_node, entity);
 		break;
+	case SDCA_ENTITY_TYPE_GE:
+		ret = find_sdca_entity_ge(dev, entity_node, entity);
+		break;
 	default:
 		break;
 	}
@@ -1384,6 +1473,42 @@ static int find_sdca_entity_connection_pde(struct device *dev,
 	return 0;
 }
 
+static int find_sdca_entity_connection_ge(struct device *dev,
+					  struct sdca_function_data *function,
+					  struct fwnode_handle *entity_node,
+					  struct sdca_entity *entity)
+{
+	int i, j;
+
+	for (i = 0; i < entity->ge.num_modes; i++) {
+		struct sdca_ge_mode *mode = &entity->ge.modes[i];
+
+		for (j = 0; j < mode->num_controls; j++) {
+			struct sdca_ge_control *affected = &mode->controls[j];
+			struct sdca_entity *managed;
+
+			managed = find_sdca_entity_by_id(function, affected->id);
+			if (!managed) {
+				dev_err(dev, "%s: failed to find entity with id %#x\n",
+					entity->label, affected->id);
+				return -EINVAL;
+			}
+
+			if (managed->group && managed->group != entity) {
+				dev_err(dev,
+					"%s: entity controlled by two groups %s, %s\n",
+					managed->label, managed->group->label,
+					entity->label);
+				return -EINVAL;
+			}
+
+			managed->group = entity;
+		}
+	}
+
+	return 0;
+}
+
 static int find_sdca_entity_connection(struct device *dev,
 				       struct sdca_function_data *function,
 				       struct fwnode_handle *entity_node,
@@ -1404,6 +1529,10 @@ static int find_sdca_entity_connection(struct device *dev,
 		ret = find_sdca_entity_connection_pde(dev, function,
 						      entity_node, entity);
 		break;
+	case SDCA_ENTITY_TYPE_GE:
+		ret = find_sdca_entity_connection_ge(dev, function,
+						     entity_node, entity);
+		break;
 	default:
 		ret = 0;
 		break;
-- 
2.39.5