diff options
Diffstat (limited to 'drivers/media/rc/imon_raw.c')
| -rw-r--r-- | drivers/media/rc/imon_raw.c | 217 |
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); |