1 files changed, 127 insertions, 0 deletions
diff --git a/sound/soc/sdca/sdca_hid.c b/sound/soc/sdca/sdca_hid.c
new file mode 100644
index 000000000000..967f7ec6fb79
--- /dev/null
+++ b/sound/soc/sdca/sdca_hid.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+
+/*
+ * The MIPI SDCA specification is available for public downloads at
+ * https://www.mipi.org/mipi-sdca-v1-0-download
+ */
+
+#include <linux/acpi.h>
+#include <linux/byteorder/generic.h>
+#include <linux/cleanup.h>
+#include <linux/device.h>
+#include <linux/dev_printk.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/soundwire/sdw.h>
+#include <linux/types.h>
+#include <sound/sdca.h>
+#include <sound/sdca_function.h>
+#include <sound/sdca_hid.h>
+
+static int sdwhid_parse(struct hid_device *hid)
+{
+	struct sdca_entity *entity = hid->driver_data;
+	unsigned int rsize;
+	int ret;
+
+	rsize = le16_to_cpu(entity->hide.hid_desc.rpt_desc.wDescriptorLength);
+
+	if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
+		dev_err(&hid->dev, "invalid size of report descriptor (%u)\n", rsize);
+		return -EINVAL;
+	}
+
+	ret = hid_parse_report(hid, entity->hide.hid_report_desc, rsize);
+
+	if (!ret)
+		return 0;
+
+	dev_err(&hid->dev, "parsing report descriptor failed\n");
+	return ret;
+}
+
+static int sdwhid_start(struct hid_device *hid)
+{
+	return 0;
+}
+
+static void sdwhid_stop(struct hid_device *hid)
+{
+}
+
+static int sdwhid_raw_request(struct hid_device *hid, unsigned char reportnum,
+			      __u8 *buf, size_t len, unsigned char rtype, int reqtype)
+{
+	switch (reqtype) {
+	case HID_REQ_GET_REPORT:
+		/* not implemented yet */
+		return 0;
+	case HID_REQ_SET_REPORT:
+		/* not implemented yet */
+		return 0;
+	default:
+		return -EIO;
+	}
+}
+
+static int sdwhid_open(struct hid_device *hid)
+{
+	return 0;
+}
+
+static void sdwhid_close(struct hid_device *hid)
+{
+}
+
+static const struct hid_ll_driver sdw_hid_driver = {
+	.parse = sdwhid_parse,
+	.start = sdwhid_start,
+	.stop = sdwhid_stop,
+	.open = sdwhid_open,
+	.close = sdwhid_close,
+	.raw_request = sdwhid_raw_request,
+};
+
+int sdca_add_hid_device(struct device *dev, struct sdca_entity *entity)
+{
+	struct sdw_bus *bus;
+	struct hid_device *hid;
+	struct sdw_slave *slave = dev_to_sdw_dev(dev);
+	int ret;
+
+	bus = slave->bus;
+
+	hid = hid_allocate_device();
+	if (IS_ERR(hid))
+		return PTR_ERR(hid);
+
+	hid->ll_driver = &sdw_hid_driver;
+
+	hid->dev.parent = dev;
+	hid->bus = BUS_SDW;
+	hid->version = le16_to_cpu(entity->hide.hid_desc.bcdHID);
+
+	snprintf(hid->name, sizeof(hid->name),
+		 "HID sdw:%01x:%01x:%04x:%04x:%02x",
+		 bus->controller_id, bus->link_id, slave->id.mfg_id,
+		 slave->id.part_id, slave->id.class_id);
+
+	snprintf(hid->phys, sizeof(hid->phys), "%s", dev->bus->name);
+
+	hid->driver_data = entity;
+
+	ret = hid_add_device(hid);
+	if (ret && ret != -ENODEV) {
+		dev_err(dev, "can't add hid device: %d\n", ret);
+		hid_destroy_device(hid);
+		return ret;
+	}
+
+	entity->hide.hid = hid;
+
+	return 0;
+}
+EXPORT_SYMBOL_NS(sdca_add_hid_device, "SND_SOC_SDCA");
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("SDCA HID library");