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1// SPDX-License-Identifier: GPL-2.0+2//3// Copyright (C) 2018 Sean Young <sean@mess.org>4 5#include <linux/module.h>6#include <linux/usb.h>7#include <linux/usb/input.h>8#include <media/rc-core.h>9 10/* Each bit is 250us */11#define BIT_DURATION 25012 13struct imon {14 struct device *dev;15 struct urb *ir_urb;16 struct rc_dev *rcdev;17 __be64 *ir_buf;18 char phys[64];19};20 21/*22 * The first 5 bytes of data represent IR pulse or space. Each bit, starting23 * from highest bit in the first byte, represents 250µs of data. It is 124 * for space and 0 for pulse.25 *26 * The station sends 10 packets, and the 7th byte will be number 1 to 10, so27 * when we receive 10 we assume all the data has arrived.28 */29static void imon_ir_data(struct imon *imon)30{31 struct ir_raw_event rawir = {};32 u64 data = be64_to_cpup(imon->ir_buf);33 u8 packet_no = data & 0xff;34 int offset = 40;35 int bit;36 37 if (packet_no == 0xff)38 return;39 40 dev_dbg(imon->dev, "data: %*ph", 8, imon->ir_buf);41 42 /*43 * Only the first 5 bytes contain IR data. Right shift so we move44 * the IR bits to the lower 40 bits.45 */46 data >>= 24;47 48 do {49 /*50 * Find highest set bit which is less or equal to offset51 *52 * offset is the bit above (base 0) where we start looking.53 *54 * data & (BIT_ULL(offset) - 1) masks off any unwanted bits,55 * so we have just bits less than offset.56 *57 * fls will tell us the highest bit set plus 1 (or 0 if no58 * bits are set).59 */60 rawir.pulse = !rawir.pulse;61 bit = fls64(data & (BIT_ULL(offset) - 1));62 if (bit < offset) {63 dev_dbg(imon->dev, "%s: %d bits",64 rawir.pulse ? "pulse" : "space", offset - bit);65 rawir.duration = (offset - bit) * BIT_DURATION;66 ir_raw_event_store_with_filter(imon->rcdev, &rawir);67 68 offset = bit;69 }70 71 data = ~data;72 } while (offset > 0);73 74 if (packet_no == 0x0a && !imon->rcdev->idle) {75 ir_raw_event_set_idle(imon->rcdev, true);76 ir_raw_event_handle(imon->rcdev);77 }78}79 80static void imon_ir_rx(struct urb *urb)81{82 struct imon *imon = urb->context;83 int ret;84 85 switch (urb->status) {86 case 0:87 imon_ir_data(imon);88 break;89 case -ECONNRESET:90 case -ENOENT:91 case -ESHUTDOWN:92 usb_unlink_urb(urb);93 return;94 case -EPIPE:95 default:96 dev_dbg(imon->dev, "error: urb status = %d", urb->status);97 break;98 }99 100 ret = usb_submit_urb(urb, GFP_ATOMIC);101 if (ret && ret != -ENODEV)102 dev_warn(imon->dev, "failed to resubmit urb: %d", ret);103}104 105static int imon_probe(struct usb_interface *intf,106 const struct usb_device_id *id)107{108 struct usb_endpoint_descriptor *ir_ep = NULL;109 struct usb_host_interface *idesc;110 struct usb_device *udev;111 struct rc_dev *rcdev;112 struct imon *imon;113 int i, ret;114 115 udev = interface_to_usbdev(intf);116 idesc = intf->cur_altsetting;117 118 for (i = 0; i < idesc->desc.bNumEndpoints; i++) {119 struct usb_endpoint_descriptor *ep = &idesc->endpoint[i].desc;120 121 if (usb_endpoint_is_int_in(ep)) {122 ir_ep = ep;123 break;124 }125 }126 127 if (!ir_ep) {128 dev_err(&intf->dev, "IR endpoint missing");129 return -ENODEV;130 }131 132 imon = devm_kmalloc(&intf->dev, sizeof(*imon), GFP_KERNEL);133 if (!imon)134 return -ENOMEM;135 136 imon->ir_urb = usb_alloc_urb(0, GFP_KERNEL);137 if (!imon->ir_urb)138 return -ENOMEM;139 140 imon->ir_buf = kmalloc(sizeof(__be64), GFP_KERNEL);141 if (!imon->ir_buf) {142 ret = -ENOMEM;143 goto free_urb;144 }145 146 imon->dev = &intf->dev;147 usb_fill_int_urb(imon->ir_urb, udev,148 usb_rcvintpipe(udev, ir_ep->bEndpointAddress),149 imon->ir_buf, sizeof(__be64),150 imon_ir_rx, imon, ir_ep->bInterval);151 152 rcdev = devm_rc_allocate_device(&intf->dev, RC_DRIVER_IR_RAW);153 if (!rcdev) {154 ret = -ENOMEM;155 goto free_urb;156 }157 158 usb_make_path(udev, imon->phys, sizeof(imon->phys));159 160 rcdev->device_name = "iMON Station";161 rcdev->driver_name = KBUILD_MODNAME;162 rcdev->input_phys = imon->phys;163 usb_to_input_id(udev, &rcdev->input_id);164 rcdev->dev.parent = &intf->dev;165 rcdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;166 rcdev->map_name = RC_MAP_IMON_RSC;167 rcdev->rx_resolution = BIT_DURATION;168 rcdev->priv = imon;169 170 ret = devm_rc_register_device(&intf->dev, rcdev);171 if (ret)172 goto free_urb;173 174 imon->rcdev = rcdev;175 176 ret = usb_submit_urb(imon->ir_urb, GFP_KERNEL);177 if (ret)178 goto free_urb;179 180 usb_set_intfdata(intf, imon);181 182 return 0;183 184free_urb:185 usb_free_urb(imon->ir_urb);186 kfree(imon->ir_buf);187 return ret;188}189 190static void imon_disconnect(struct usb_interface *intf)191{192 struct imon *imon = usb_get_intfdata(intf);193 194 usb_kill_urb(imon->ir_urb);195 usb_free_urb(imon->ir_urb);196 kfree(imon->ir_buf);197}198 199static const struct usb_device_id imon_table[] = {200 /* SoundGraph iMON (IR only) -- sg_imon.inf */201 { USB_DEVICE(0x04e8, 0xff30) },202 {}203};204 205static struct usb_driver imon_driver = {206 .name = KBUILD_MODNAME,207 .probe = imon_probe,208 .disconnect = imon_disconnect,209 .id_table = imon_table210};211 212module_usb_driver(imon_driver);213 214MODULE_DESCRIPTION("Early raw iMON IR devices");215MODULE_AUTHOR("Sean Young <sean@mess.org>");216MODULE_LICENSE("GPL");217MODULE_DEVICE_TABLE(usb, imon_table);218