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Diffstat (limited to 'drivers/media/rc/imon_raw.c')
-rw-r--r--drivers/media/rc/imon_raw.c217
1 files changed, 217 insertions, 0 deletions
diff --git a/drivers/media/rc/imon_raw.c b/drivers/media/rc/imon_raw.c
new file mode 100644
index 000000000..b02ded52f
--- /dev/null
+++ b/drivers/media/rc/imon_raw.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright (C) 2018 Sean Young <sean@mess.org>
+
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/usb/input.h>
+#include <media/rc-core.h>
+
+/* Each bit is 250us */
+#define BIT_DURATION 250
+
+struct imon {
+ struct device *dev;
+ struct urb *ir_urb;
+ struct rc_dev *rcdev;
+ __be64 *ir_buf;
+ char phys[64];
+};
+
+/*
+ * The first 5 bytes of data represent IR pulse or space. Each bit, starting
+ * from highest bit in the first byte, represents 250µs of data. It is 1
+ * for space and 0 for pulse.
+ *
+ * The station sends 10 packets, and the 7th byte will be number 1 to 10, so
+ * when we receive 10 we assume all the data has arrived.
+ */
+static void imon_ir_data(struct imon *imon)
+{
+ struct ir_raw_event rawir = {};
+ u64 data = be64_to_cpup(imon->ir_buf);
+ u8 packet_no = data & 0xff;
+ int offset = 40;
+ int bit;
+
+ if (packet_no == 0xff)
+ return;
+
+ dev_dbg(imon->dev, "data: %*ph", 8, imon->ir_buf);
+
+ /*
+ * Only the first 5 bytes contain IR data. Right shift so we move
+ * the IR bits to the lower 40 bits.
+ */
+ data >>= 24;
+
+ do {
+ /*
+ * Find highest set bit which is less or equal to offset
+ *
+ * offset is the bit above (base 0) where we start looking.
+ *
+ * data & (BIT_ULL(offset) - 1) masks off any unwanted bits,
+ * so we have just bits less than offset.
+ *
+ * fls will tell us the highest bit set plus 1 (or 0 if no
+ * bits are set).
+ */
+ rawir.pulse = !rawir.pulse;
+ bit = fls64(data & (BIT_ULL(offset) - 1));
+ if (bit < offset) {
+ dev_dbg(imon->dev, "%s: %d bits",
+ rawir.pulse ? "pulse" : "space", offset - bit);
+ rawir.duration = (offset - bit) * BIT_DURATION;
+ ir_raw_event_store_with_filter(imon->rcdev, &rawir);
+
+ offset = bit;
+ }
+
+ data = ~data;
+ } while (offset > 0);
+
+ if (packet_no == 0x0a && !imon->rcdev->idle) {
+ ir_raw_event_set_idle(imon->rcdev, true);
+ ir_raw_event_handle(imon->rcdev);
+ }
+}
+
+static void imon_ir_rx(struct urb *urb)
+{
+ struct imon *imon = urb->context;
+ int ret;
+
+ switch (urb->status) {
+ case 0:
+ imon_ir_data(imon);
+ break;
+ case -ECONNRESET:
+ case -ENOENT:
+ case -ESHUTDOWN:
+ usb_unlink_urb(urb);
+ return;
+ case -EPIPE:
+ default:
+ dev_dbg(imon->dev, "error: urb status = %d", urb->status);
+ break;
+ }
+
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret && ret != -ENODEV)
+ dev_warn(imon->dev, "failed to resubmit urb: %d", ret);
+}
+
+static int imon_probe(struct usb_interface *intf,
+ const struct usb_device_id *id)
+{
+ struct usb_endpoint_descriptor *ir_ep = NULL;
+ struct usb_host_interface *idesc;
+ struct usb_device *udev;
+ struct rc_dev *rcdev;
+ struct imon *imon;
+ int i, ret;
+
+ udev = interface_to_usbdev(intf);
+ idesc = intf->cur_altsetting;
+
+ for (i = 0; i < idesc->desc.bNumEndpoints; i++) {
+ struct usb_endpoint_descriptor *ep = &idesc->endpoint[i].desc;
+
+ if (usb_endpoint_is_int_in(ep)) {
+ ir_ep = ep;
+ break;
+ }
+ }
+
+ if (!ir_ep) {
+ dev_err(&intf->dev, "IR endpoint missing");
+ return -ENODEV;
+ }
+
+ imon = devm_kmalloc(&intf->dev, sizeof(*imon), GFP_KERNEL);
+ if (!imon)
+ return -ENOMEM;
+
+ imon->ir_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!imon->ir_urb)
+ return -ENOMEM;
+
+ imon->ir_buf = kmalloc(sizeof(__be64), GFP_KERNEL);
+ if (!imon->ir_buf) {
+ ret = -ENOMEM;
+ goto free_urb;
+ }
+
+ imon->dev = &intf->dev;
+ usb_fill_int_urb(imon->ir_urb, udev,
+ usb_rcvintpipe(udev, ir_ep->bEndpointAddress),
+ imon->ir_buf, sizeof(__be64),
+ imon_ir_rx, imon, ir_ep->bInterval);
+
+ rcdev = devm_rc_allocate_device(&intf->dev, RC_DRIVER_IR_RAW);
+ if (!rcdev) {
+ ret = -ENOMEM;
+ goto free_urb;
+ }
+
+ usb_make_path(udev, imon->phys, sizeof(imon->phys));
+
+ rcdev->device_name = "iMON Station";
+ rcdev->driver_name = KBUILD_MODNAME;
+ rcdev->input_phys = imon->phys;
+ usb_to_input_id(udev, &rcdev->input_id);
+ rcdev->dev.parent = &intf->dev;
+ rcdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
+ rcdev->map_name = RC_MAP_IMON_RSC;
+ rcdev->rx_resolution = BIT_DURATION;
+ rcdev->priv = imon;
+
+ ret = devm_rc_register_device(&intf->dev, rcdev);
+ if (ret)
+ goto free_urb;
+
+ imon->rcdev = rcdev;
+
+ ret = usb_submit_urb(imon->ir_urb, GFP_KERNEL);
+ if (ret)
+ goto free_urb;
+
+ usb_set_intfdata(intf, imon);
+
+ return 0;
+
+free_urb:
+ usb_free_urb(imon->ir_urb);
+ kfree(imon->ir_buf);
+ return ret;
+}
+
+static void imon_disconnect(struct usb_interface *intf)
+{
+ struct imon *imon = usb_get_intfdata(intf);
+
+ usb_kill_urb(imon->ir_urb);
+ usb_free_urb(imon->ir_urb);
+ kfree(imon->ir_buf);
+}
+
+static const struct usb_device_id imon_table[] = {
+ /* SoundGraph iMON (IR only) -- sg_imon.inf */
+ { USB_DEVICE(0x04e8, 0xff30) },
+ {}
+};
+
+static struct usb_driver imon_driver = {
+ .name = KBUILD_MODNAME,
+ .probe = imon_probe,
+ .disconnect = imon_disconnect,
+ .id_table = imon_table
+};
+
+module_usb_driver(imon_driver);
+
+MODULE_DESCRIPTION("Early raw iMON IR devices");
+MODULE_AUTHOR("Sean Young <sean@mess.org>");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(usb, imon_table);