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 /* 10 */ 11 12 #include <linux/serio.h> 13 #include "iforce.h" 14 15 struct iforce_serio { 16 struct iforce iforce; 17 18 struct serio *serio; 19 int idx, pkt, len, id; 20 u8 csum; 21 u8 expect_packet; 22 u8 cmd_response[IFORCE_MAX_LENGTH]; 23 u8 cmd_response_len; 24 u8 data_in[IFORCE_MAX_LENGTH]; 25 }; 26 27 static void iforce_serio_xmit(struct iforce *iforce) 28 { 29 struct iforce_serio *iforce_serio = container_of(iforce, 30 struct iforce_serio, 31 iforce); 32 unsigned char cs; 33 int i; 34 unsigned long flags; 35 36 if (test_and_set_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags)) { 37 set_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags); 38 return; 39 } 40 41 spin_lock_irqsave(&iforce->xmit_lock, flags); 42 43 again: 44 if (iforce->xmit.head == iforce->xmit.tail) { 45 clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags); 46 spin_unlock_irqrestore(&iforce->xmit_lock, flags); 47 return; 48 } 49 50 cs = 0x2b; 51 52 serio_write(iforce_serio->serio, 0x2b); 53 54 serio_write(iforce_serio->serio, iforce->xmit.buf[iforce->xmit.tail]); 55 cs ^= iforce->xmit.buf[iforce->xmit.tail]; 56 XMIT_INC(iforce->xmit.tail, 1); 57 58 for (i=iforce->xmit.buf[iforce->xmit.tail]; i >= 0; --i) { 59 serio_write(iforce_serio->serio, 60 iforce->xmit.buf[iforce->xmit.tail]); 61 cs ^= iforce->xmit.buf[iforce->xmit.tail]; 62 XMIT_INC(iforce->xmit.tail, 1); 63 } 64 65 serio_write(iforce_serio->serio, cs); 66 67 if (test_and_clear_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags)) 68 goto again; 69 70 clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags); 71 72 spin_unlock_irqrestore(&iforce->xmit_lock, flags); 73 } 74 75 static int iforce_serio_get_id(struct iforce *iforce, u8 id, 76 u8 *response_data, size_t *response_len) 77 { 78 struct iforce_serio *iforce_serio = container_of(iforce, 79 struct iforce_serio, 80 iforce); 81 82 iforce_serio->expect_packet = HI(FF_CMD_QUERY); 83 iforce_serio->cmd_response_len = 0; 84 85 iforce_send_packet(iforce, FF_CMD_QUERY, &id); 86 87 wait_event_interruptible_timeout(iforce->wait, 88 !iforce_serio->expect_packet, HZ); 89 90 if (iforce_serio->expect_packet) { 91 iforce_serio->expect_packet = 0; 92 return -ETIMEDOUT; 93 } 94 95 if (iforce_serio->cmd_response[0] != id) 96 return -EIO; 97 98 memcpy(response_data, iforce_serio->cmd_response, 99 iforce_serio->cmd_response_len); 100 *response_len = iforce_serio->cmd_response_len; 101 102 return 0; 103 } 104 105 static int iforce_serio_start_io(struct iforce *iforce) 106 { 107 /* No special handling required */ 108 return 0; 109 } 110 111 static void iforce_serio_stop_io(struct iforce *iforce) 112 { 113 //TODO: Wait for the last packets to be sent 114 } 115 116 static const struct iforce_xport_ops iforce_serio_xport_ops = { 117 .xmit = iforce_serio_xmit, 118 .get_id = iforce_serio_get_id, 119 .start_io = iforce_serio_start_io, 120 .stop_io = iforce_serio_stop_io, 121 }; 122 123 static void iforce_serio_write_wakeup(struct serio *serio) 124 { 125 struct iforce *iforce = serio_get_drvdata(serio); 126 127 iforce_serio_xmit(iforce); 128 } 129 130 static irqreturn_t iforce_serio_irq(struct serio *serio, 131 unsigned char data, unsigned int flags) 132 { 133 struct iforce_serio *iforce_serio = serio_get_drvdata(serio); 134 struct iforce *iforce = &iforce_serio->iforce; 135 136 if (!iforce_serio->pkt) { 137 if (data == 0x2b) 138 iforce_serio->pkt = 1; 139 goto out; 140 } 141 142 if (!iforce_serio->id) { 143 if (data > 3 && data != 0xff) 144 iforce_serio->pkt = 0; 145 else 146 iforce_serio->id = data; 147 goto out; 148 } 149 150 if (!iforce_serio->len) { 151 if (data > IFORCE_MAX_LENGTH) { 152 iforce_serio->pkt = 0; 153 iforce_serio->id = 0; 154 } else { 155 iforce_serio->len = data; 156 } 157 goto out; 158 } 159 160 if (iforce_serio->idx < iforce_serio->len) { 161 iforce_serio->data_in[iforce_serio->idx++] = data; 162 iforce_serio->csum += data; 163 goto out; 164 } 165 166 if (iforce_serio->idx == iforce_serio->len) { 167 /* Handle command completion */ 168 if (iforce_serio->expect_packet == iforce_serio->id) { 169 iforce_serio->expect_packet = 0; 170 memcpy(iforce_serio->cmd_response, 171 iforce_serio->data_in, IFORCE_MAX_LENGTH); 172 iforce_serio->cmd_response_len = iforce_serio->len; 173 174 /* Signal that command is done */ 175 wake_up(&iforce->wait); 176 } else if (likely(iforce->type)) { 177 iforce_process_packet(iforce, iforce_serio->id, 178 iforce_serio->data_in, 179 iforce_serio->len); 180 } 181 182 iforce_serio->pkt = 0; 183 iforce_serio->id = 0; 184 iforce_serio->len = 0; 185 iforce_serio->idx = 0; 186 iforce_serio->csum = 0; 187 } 188 out: 189 return IRQ_HANDLED; 190 } 191 192 static int iforce_serio_connect(struct serio *serio, struct serio_driver *drv) 193 { 194 struct iforce_serio *iforce_serio; 195 int err; 196 197 iforce_serio = kzalloc(sizeof(*iforce_serio), GFP_KERNEL); 198 if (!iforce_serio) 199 return -ENOMEM; 200 201 iforce_serio->iforce.xport_ops = &iforce_serio_xport_ops; 202 203 iforce_serio->serio = serio; 204 serio_set_drvdata(serio, iforce_serio); 205 206 err = serio_open(serio, drv); 207 if (err) 208 goto fail1; 209 210 err = iforce_init_device(&serio->dev, BUS_RS232, &iforce_serio->iforce); 211 if (err) 212 goto fail2; 213 214 return 0; 215 216 fail2: serio_close(serio); 217 fail1: serio_set_drvdata(serio, NULL); 218 kfree(iforce_serio); 219 return err; 220 } 221 222 static void iforce_serio_disconnect(struct serio *serio) 223 { 224 struct iforce_serio *iforce_serio = serio_get_drvdata(serio); 225 226 input_unregister_device(iforce_serio->iforce.dev); 227 serio_close(serio); 228 serio_set_drvdata(serio, NULL); 229 kfree(iforce_serio); 230 } 231 232 static const struct serio_device_id iforce_serio_ids[] = { 233 { 234 .type = SERIO_RS232, 235 .proto = SERIO_IFORCE, 236 .id = SERIO_ANY, 237 .extra = SERIO_ANY, 238 }, 239 { 0 } 240 }; 241 242 MODULE_DEVICE_TABLE(serio, iforce_serio_ids); 243 244 struct serio_driver iforce_serio_drv = { 245 .driver = { 246 .name = "iforce", 247 }, 248 .description = "RS232 I-Force joysticks and wheels driver", 249 .id_table = iforce_serio_ids, 250 .write_wakeup = iforce_serio_write_wakeup, 251 .interrupt = iforce_serio_irq, 252 .connect = iforce_serio_connect, 253 .disconnect = iforce_serio_disconnect, 254 }; 255 256 module_serio_driver(iforce_serio_drv); 257 258 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>, Johann Deneux <johann.deneux@gmail.com>"); 259 MODULE_DESCRIPTION("RS232 I-Force joysticks and wheels driver"); 260 MODULE_LICENSE("GPL"); 261