// 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);