1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (c) 2000-2001 Vojtech Pavlik <vojtech@ucw.cz> 4 * Copyright (c) 2001, 2007 Johann Deneux <johann.deneux@gmail.com> 5 * 6 * USB/RS232 I-Force joysticks and wheels. 7 */ 8 9 #include <linux/serio.h> 10 #include "iforce.h" 11 12 struct iforce_serio { 13 struct iforce iforce; 14 15 struct serio *serio; 16 int idx, pkt, len, id; 17 u8 csum; 18 u8 expect_packet; 19 u8 cmd_response[IFORCE_MAX_LENGTH]; 20 u8 cmd_response_len; 21 u8 data_in[IFORCE_MAX_LENGTH]; 22 }; 23 24 static void iforce_serio_xmit(struct iforce *iforce) 25 { 26 struct iforce_serio *iforce_serio = container_of(iforce, 27 struct iforce_serio, 28 iforce); 29 unsigned char cs; 30 int i; 31 unsigned long flags; 32 33 if (test_and_set_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags)) { 34 set_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags); 35 return; 36 } 37 38 spin_lock_irqsave(&iforce->xmit_lock, flags); 39 40 again: 41 if (iforce->xmit.head == iforce->xmit.tail) { 42 iforce_clear_xmit_and_wake(iforce); 43 spin_unlock_irqrestore(&iforce->xmit_lock, flags); 44 return; 45 } 46 47 cs = 0x2b; 48 49 serio_write(iforce_serio->serio, 0x2b); 50 51 serio_write(iforce_serio->serio, iforce->xmit.buf[iforce->xmit.tail]); 52 cs ^= iforce->xmit.buf[iforce->xmit.tail]; 53 XMIT_INC(iforce->xmit.tail, 1); 54 55 for (i=iforce->xmit.buf[iforce->xmit.tail]; i >= 0; --i) { 56 serio_write(iforce_serio->serio, 57 iforce->xmit.buf[iforce->xmit.tail]); 58 cs ^= iforce->xmit.buf[iforce->xmit.tail]; 59 XMIT_INC(iforce->xmit.tail, 1); 60 } 61 62 serio_write(iforce_serio->serio, cs); 63 64 if (test_and_clear_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags)) 65 goto again; 66 67 iforce_clear_xmit_and_wake(iforce); 68 69 spin_unlock_irqrestore(&iforce->xmit_lock, flags); 70 } 71 72 static int iforce_serio_get_id(struct iforce *iforce, u8 id, 73 u8 *response_data, size_t *response_len) 74 { 75 struct iforce_serio *iforce_serio = container_of(iforce, 76 struct iforce_serio, 77 iforce); 78 79 iforce_serio->expect_packet = HI(FF_CMD_QUERY); 80 iforce_serio->cmd_response_len = 0; 81 82 iforce_send_packet(iforce, FF_CMD_QUERY, &id); 83 84 wait_event_interruptible_timeout(iforce->wait, 85 !iforce_serio->expect_packet, HZ); 86 87 if (iforce_serio->expect_packet) { 88 iforce_serio->expect_packet = 0; 89 return -ETIMEDOUT; 90 } 91 92 if (iforce_serio->cmd_response[0] != id) 93 return -EIO; 94 95 memcpy(response_data, iforce_serio->cmd_response, 96 iforce_serio->cmd_response_len); 97 *response_len = iforce_serio->cmd_response_len; 98 99 return 0; 100 } 101 102 static int iforce_serio_start_io(struct iforce *iforce) 103 { 104 /* No special handling required */ 105 return 0; 106 } 107 108 static void iforce_serio_stop_io(struct iforce *iforce) 109 { 110 //TODO: Wait for the last packets to be sent 111 } 112 113 static const struct iforce_xport_ops iforce_serio_xport_ops = { 114 .xmit = iforce_serio_xmit, 115 .get_id = iforce_serio_get_id, 116 .start_io = iforce_serio_start_io, 117 .stop_io = iforce_serio_stop_io, 118 }; 119 120 static void iforce_serio_write_wakeup(struct serio *serio) 121 { 122 struct iforce *iforce = serio_get_drvdata(serio); 123 124 iforce_serio_xmit(iforce); 125 } 126 127 static irqreturn_t iforce_serio_irq(struct serio *serio, 128 unsigned char data, unsigned int flags) 129 { 130 struct iforce_serio *iforce_serio = serio_get_drvdata(serio); 131 struct iforce *iforce = &iforce_serio->iforce; 132 133 if (!iforce_serio->pkt) { 134 if (data == 0x2b) 135 iforce_serio->pkt = 1; 136 goto out; 137 } 138 139 if (!iforce_serio->id) { 140 if (data > 3 && data != 0xff) 141 iforce_serio->pkt = 0; 142 else 143 iforce_serio->id = data; 144 goto out; 145 } 146 147 if (!iforce_serio->len) { 148 if (data > IFORCE_MAX_LENGTH) { 149 iforce_serio->pkt = 0; 150 iforce_serio->id = 0; 151 } else { 152 iforce_serio->len = data; 153 } 154 goto out; 155 } 156 157 if (iforce_serio->idx < iforce_serio->len) { 158 iforce_serio->data_in[iforce_serio->idx++] = data; 159 iforce_serio->csum += data; 160 goto out; 161 } 162 163 if (iforce_serio->idx == iforce_serio->len) { 164 /* Handle command completion */ 165 if (iforce_serio->expect_packet == iforce_serio->id) { 166 iforce_serio->expect_packet = 0; 167 memcpy(iforce_serio->cmd_response, 168 iforce_serio->data_in, IFORCE_MAX_LENGTH); 169 iforce_serio->cmd_response_len = iforce_serio->len; 170 171 /* Signal that command is done */ 172 wake_up_all(&iforce->wait); 173 } else if (likely(iforce->type)) { 174 iforce_process_packet(iforce, iforce_serio->id, 175 iforce_serio->data_in, 176 iforce_serio->len); 177 } 178 179 iforce_serio->pkt = 0; 180 iforce_serio->id = 0; 181 iforce_serio->len = 0; 182 iforce_serio->idx = 0; 183 iforce_serio->csum = 0; 184 } 185 out: 186 return IRQ_HANDLED; 187 } 188 189 static int iforce_serio_connect(struct serio *serio, struct serio_driver *drv) 190 { 191 struct iforce_serio *iforce_serio; 192 int err; 193 194 iforce_serio = kzalloc(sizeof(*iforce_serio), GFP_KERNEL); 195 if (!iforce_serio) 196 return -ENOMEM; 197 198 iforce_serio->iforce.xport_ops = &iforce_serio_xport_ops; 199 200 iforce_serio->serio = serio; 201 serio_set_drvdata(serio, iforce_serio); 202 203 err = serio_open(serio, drv); 204 if (err) 205 goto fail1; 206 207 err = iforce_init_device(&serio->dev, BUS_RS232, &iforce_serio->iforce); 208 if (err) 209 goto fail2; 210 211 return 0; 212 213 fail2: serio_close(serio); 214 fail1: serio_set_drvdata(serio, NULL); 215 kfree(iforce_serio); 216 return err; 217 } 218 219 static void iforce_serio_disconnect(struct serio *serio) 220 { 221 struct iforce_serio *iforce_serio = serio_get_drvdata(serio); 222 223 input_unregister_device(iforce_serio->iforce.dev); 224 serio_close(serio); 225 serio_set_drvdata(serio, NULL); 226 kfree(iforce_serio); 227 } 228 229 static const struct serio_device_id iforce_serio_ids[] = { 230 { 231 .type = SERIO_RS232, 232 .proto = SERIO_IFORCE, 233 .id = SERIO_ANY, 234 .extra = SERIO_ANY, 235 }, 236 { 0 } 237 }; 238 239 MODULE_DEVICE_TABLE(serio, iforce_serio_ids); 240 241 struct serio_driver iforce_serio_drv = { 242 .driver = { 243 .name = "iforce", 244 }, 245 .description = "RS232 I-Force joysticks and wheels driver", 246 .id_table = iforce_serio_ids, 247 .write_wakeup = iforce_serio_write_wakeup, 248 .interrupt = iforce_serio_irq, 249 .connect = iforce_serio_connect, 250 .disconnect = iforce_serio_disconnect, 251 }; 252 253 module_serio_driver(iforce_serio_drv); 254 255 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>, Johann Deneux <johann.deneux@gmail.com>"); 256 MODULE_DESCRIPTION("RS232 I-Force joysticks and wheels driver"); 257 MODULE_LICENSE("GPL"); 258