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 250000 12 13 struct imon { 14 struct device *dev; 15 struct urb *ir_urb; 16 struct rc_dev *rcdev; 17 u8 ir_buf[8] __aligned(__alignof__(u64)); 18 char phys[64]; 19 }; 20 21 /* 22 * The first 5 bytes of data represent IR pulse or space. Each bit, starting 23 * from highest bit in the first byte, represents 250µs of data. It is 1 24 * for space and 0 for pulse. 25 * 26 * The station sends 10 packets, and the 7th byte will be number 1 to 10, so 27 * when we receive 10 we assume all the data has arrived. 28 */ 29 static void imon_ir_data(struct imon *imon) 30 { 31 struct ir_raw_event rawir = {}; 32 u64 d = be64_to_cpup((__be64 *)imon->ir_buf) >> 24; 33 int offset = 40; 34 int bit; 35 36 dev_dbg(imon->dev, "data: %*ph", 8, imon->ir_buf); 37 38 do { 39 bit = fls64(d & (BIT_ULL(offset) - 1)); 40 if (bit < offset) { 41 dev_dbg(imon->dev, "pulse: %d bits", offset - bit); 42 rawir.pulse = true; 43 rawir.duration = (offset - bit) * BIT_DURATION; 44 ir_raw_event_store_with_filter(imon->rcdev, &rawir); 45 46 if (bit == 0) 47 break; 48 49 offset = bit; 50 } 51 52 bit = fls64(~d & (BIT_ULL(offset) - 1)); 53 dev_dbg(imon->dev, "space: %d bits", offset - bit); 54 55 rawir.pulse = false; 56 rawir.duration = (offset - bit) * BIT_DURATION; 57 ir_raw_event_store_with_filter(imon->rcdev, &rawir); 58 59 offset = bit; 60 } while (offset > 0); 61 62 if (imon->ir_buf[7] == 0x0a) { 63 ir_raw_event_set_idle(imon->rcdev, true); 64 ir_raw_event_handle(imon->rcdev); 65 } 66 } 67 68 static void imon_ir_rx(struct urb *urb) 69 { 70 struct imon *imon = urb->context; 71 int ret; 72 73 switch (urb->status) { 74 case 0: 75 if (imon->ir_buf[7] != 0xff) 76 imon_ir_data(imon); 77 break; 78 case -ECONNRESET: 79 case -ENOENT: 80 case -ESHUTDOWN: 81 usb_unlink_urb(urb); 82 return; 83 case -EPIPE: 84 default: 85 dev_dbg(imon->dev, "error: urb status = %d", urb->status); 86 break; 87 } 88 89 ret = usb_submit_urb(urb, GFP_ATOMIC); 90 if (ret && ret != -ENODEV) 91 dev_warn(imon->dev, "failed to resubmit urb: %d", ret); 92 } 93 94 static int imon_probe(struct usb_interface *intf, 95 const struct usb_device_id *id) 96 { 97 struct usb_endpoint_descriptor *ir_ep = NULL; 98 struct usb_host_interface *idesc; 99 struct usb_device *udev; 100 struct rc_dev *rcdev; 101 struct imon *imon; 102 int i, ret; 103 104 udev = interface_to_usbdev(intf); 105 idesc = intf->cur_altsetting; 106 107 for (i = 0; i < idesc->desc.bNumEndpoints; i++) { 108 struct usb_endpoint_descriptor *ep = &idesc->endpoint[i].desc; 109 110 if (usb_endpoint_is_int_in(ep)) { 111 ir_ep = ep; 112 break; 113 } 114 } 115 116 if (!ir_ep) { 117 dev_err(&intf->dev, "IR endpoint missing"); 118 return -ENODEV; 119 } 120 121 imon = devm_kmalloc(&intf->dev, sizeof(*imon), GFP_KERNEL); 122 if (!imon) 123 return -ENOMEM; 124 125 imon->ir_urb = usb_alloc_urb(0, GFP_KERNEL); 126 if (!imon->ir_urb) 127 return -ENOMEM; 128 129 imon->dev = &intf->dev; 130 usb_fill_int_urb(imon->ir_urb, udev, 131 usb_rcvintpipe(udev, ir_ep->bEndpointAddress), 132 imon->ir_buf, sizeof(imon->ir_buf), 133 imon_ir_rx, imon, ir_ep->bInterval); 134 135 rcdev = devm_rc_allocate_device(&intf->dev, RC_DRIVER_IR_RAW); 136 if (!rcdev) { 137 ret = -ENOMEM; 138 goto free_urb; 139 } 140 141 usb_make_path(udev, imon->phys, sizeof(imon->phys)); 142 143 rcdev->device_name = "iMON Station"; 144 rcdev->driver_name = KBUILD_MODNAME; 145 rcdev->input_phys = imon->phys; 146 usb_to_input_id(udev, &rcdev->input_id); 147 rcdev->dev.parent = &intf->dev; 148 rcdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER; 149 rcdev->map_name = RC_MAP_IMON_RSC; 150 rcdev->rx_resolution = BIT_DURATION; 151 rcdev->priv = imon; 152 153 ret = devm_rc_register_device(&intf->dev, rcdev); 154 if (ret) 155 goto free_urb; 156 157 imon->rcdev = rcdev; 158 159 ret = usb_submit_urb(imon->ir_urb, GFP_KERNEL); 160 if (ret) 161 goto free_urb; 162 163 usb_set_intfdata(intf, imon); 164 165 return 0; 166 167 free_urb: 168 usb_free_urb(imon->ir_urb); 169 return ret; 170 } 171 172 static void imon_disconnect(struct usb_interface *intf) 173 { 174 struct imon *imon = usb_get_intfdata(intf); 175 176 usb_kill_urb(imon->ir_urb); 177 usb_free_urb(imon->ir_urb); 178 } 179 180 static const struct usb_device_id imon_table[] = { 181 /* SoundGraph iMON (IR only) -- sg_imon.inf */ 182 { USB_DEVICE(0x04e8, 0xff30) }, 183 {} 184 }; 185 186 static struct usb_driver imon_driver = { 187 .name = KBUILD_MODNAME, 188 .probe = imon_probe, 189 .disconnect = imon_disconnect, 190 .id_table = imon_table 191 }; 192 193 module_usb_driver(imon_driver); 194 195 MODULE_DESCRIPTION("Early raw iMON IR devices"); 196 MODULE_AUTHOR("Sean Young <sean@mess.org>"); 197 MODULE_LICENSE("GPL"); 198 MODULE_DEVICE_TABLE(usb, imon_table); 199