Carl van Schaik | d157ad4 | 2018-07-03 11:34:44 +1000 | [diff] [blame] | 1 | /* |
| 2 | * drivers/char/okl4_pipe.c |
| 3 | * |
| 4 | * Copyright (c) 2015 General Dynamics |
| 5 | * Copyright (c) 2015 Open Kernel Labs, Inc. |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | * |
| 11 | * OKL4 Microvisor Pipes driver. |
| 12 | * |
| 13 | * Clients using this driver must have vclient names of the form |
| 14 | * "pipe%d", where %d is the pipe number, which must be |
| 15 | * unique and less than MAX_PIPES. |
| 16 | */ |
| 17 | |
| 18 | /* #define DEBUG 1 */ |
| 19 | /* #define VERBOSE_DEBUG 1 */ |
| 20 | |
| 21 | #include <linux/init.h> |
| 22 | #include <linux/err.h> |
| 23 | #include <linux/string.h> |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/module.h> |
| 26 | #include <linux/interrupt.h> |
| 27 | #include <linux/platform_device.h> |
| 28 | #include <linux/mutex.h> |
| 29 | #include <linux/delay.h> |
| 30 | #include <linux/workqueue.h> |
| 31 | #include <linux/slab.h> |
| 32 | #include <linux/version.h> |
| 33 | #include <linux/fs.h> |
| 34 | #include <linux/cdev.h> |
| 35 | #include <linux/poll.h> |
| 36 | #include <linux/sched.h> |
| 37 | #include <linux/wait.h> |
| 38 | #include <linux/of.h> |
| 39 | #include <asm/uaccess.h> |
| 40 | #include <asm-generic/okl4_virq.h> |
| 41 | |
| 42 | #include <microvisor/microvisor.h> |
| 43 | #if defined(CONFIG_OKL4_VIRTUALISATION) |
| 44 | #include <asm/okl4-microvisor/okl4tags.h> |
| 45 | #include <asm/okl4-microvisor/microvisor_bus.h> |
| 46 | #include <asm/okl4-microvisor/virq.h> |
| 47 | #endif |
| 48 | |
| 49 | #if LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0) |
| 50 | #define __devinit |
| 51 | #define __devexit |
| 52 | #define __devexit_p(x) x |
| 53 | #endif |
| 54 | |
| 55 | #define DRIVER_NAME "okl4-pipe" |
| 56 | #define DEVICE_NAME "okl4-pipe" |
| 57 | |
| 58 | #ifndef CONFIG_OF |
| 59 | #error "okl4-pipe driver only supported on device tree kernels" |
| 60 | #endif |
| 61 | |
| 62 | #define MAX_PIPES 8 |
| 63 | |
| 64 | #ifdef CONFIG_OKL4_INTERLEAVED_PRIORITIES |
| 65 | extern int vcpu_prio_normal; |
| 66 | #endif |
| 67 | |
| 68 | static int okl4_pipe_major; |
| 69 | static struct class *okl4_pipe_class; |
| 70 | |
| 71 | /* This can be extended if required */ |
| 72 | struct okl4_pipe_mv { |
| 73 | int pipe_id; |
| 74 | }; |
| 75 | |
| 76 | struct okl4_pipe { |
| 77 | struct okl4_pipe_data_buffer *write_buf; |
| 78 | okl4_kcap_t pipe_tx_kcap; |
| 79 | okl4_kcap_t pipe_rx_kcap; |
| 80 | int tx_irq; |
| 81 | int rx_irq; |
| 82 | size_t max_msg_size; |
| 83 | int ref_count; |
| 84 | struct mutex pipe_mutex; |
| 85 | spinlock_t pipe_lock; |
| 86 | |
| 87 | struct platform_device *pdev; |
| 88 | struct cdev cdev; |
| 89 | |
| 90 | bool reset; |
| 91 | bool tx_maybe_avail; |
| 92 | bool rx_maybe_avail; |
| 93 | |
| 94 | wait_queue_head_t rx_wait_q; |
| 95 | wait_queue_head_t tx_wait_q; |
| 96 | wait_queue_head_t poll_wait_q; |
| 97 | |
| 98 | char *rx_buf; |
| 99 | size_t rx_buf_count; |
| 100 | }; |
| 101 | static struct okl4_pipe pipes[MAX_PIPES]; |
| 102 | |
| 103 | static okl4_error_t |
| 104 | okl4_pipe_control(okl4_kcap_t kcap, uint8_t control) |
| 105 | { |
| 106 | okl4_pipe_control_t x = 0; |
| 107 | |
| 108 | okl4_pipe_control_setdoop(&x, true); |
| 109 | okl4_pipe_control_setoperation(&x, control); |
| 110 | return _okl4_sys_pipe_control(kcap, x); |
| 111 | } |
| 112 | |
| 113 | static irqreturn_t |
| 114 | okl4_pipe_tx_irq(int irq, void *dev) |
| 115 | { |
| 116 | struct okl4_pipe *pipe = dev; |
| 117 | okl4_pipe_state_t payload = okl4_get_virq_payload(irq); |
| 118 | |
| 119 | spin_lock(&pipe->pipe_lock); |
| 120 | if (okl4_pipe_state_gettxavailable(&payload)) |
| 121 | pipe->tx_maybe_avail = true; |
| 122 | if (okl4_pipe_state_getreset(&payload)) { |
| 123 | pipe->reset = true; |
| 124 | pipe->tx_maybe_avail = true; |
| 125 | } |
| 126 | spin_unlock(&pipe->pipe_lock); |
| 127 | |
| 128 | wake_up_interruptible(&pipe->tx_wait_q); |
| 129 | wake_up_interruptible(&pipe->poll_wait_q); |
| 130 | |
| 131 | return IRQ_HANDLED; |
| 132 | } |
| 133 | |
| 134 | static irqreturn_t |
| 135 | okl4_pipe_rx_irq(int irq, void *dev) |
| 136 | { |
| 137 | struct okl4_pipe *pipe = dev; |
| 138 | okl4_pipe_state_t payload = okl4_get_virq_payload(irq); |
| 139 | |
| 140 | spin_lock(&pipe->pipe_lock); |
| 141 | if (okl4_pipe_state_getrxavailable(&payload)) |
| 142 | pipe->rx_maybe_avail = true; |
| 143 | if (okl4_pipe_state_getreset(&payload)) { |
| 144 | pipe->reset = true; |
| 145 | pipe->rx_maybe_avail = true; |
| 146 | } |
| 147 | spin_unlock(&pipe->pipe_lock); |
| 148 | |
| 149 | wake_up_interruptible(&pipe->rx_wait_q); |
| 150 | wake_up_interruptible(&pipe->poll_wait_q); |
| 151 | |
| 152 | return IRQ_HANDLED; |
| 153 | } |
| 154 | |
| 155 | static ssize_t |
| 156 | okl4_pipe_read(struct file *filp, char __user *buf, size_t count, |
| 157 | loff_t *f_pos) |
| 158 | { |
| 159 | struct okl4_pipe_mv *priv = filp->private_data; |
| 160 | int pipe_id = priv->pipe_id; |
| 161 | struct okl4_pipe *pipe = &pipes[pipe_id]; |
| 162 | struct _okl4_sys_pipe_recv_return recv_return; |
| 163 | uint32_t *buffer = NULL; |
| 164 | size_t recv = 0; |
| 165 | |
| 166 | if (!count) |
| 167 | return 0; |
| 168 | |
| 169 | again: |
| 170 | if (pipe->reset) |
| 171 | return -EPIPE; |
| 172 | |
| 173 | if (!pipe->rx_maybe_avail && (filp->f_flags & O_NONBLOCK)) |
| 174 | return -EAGAIN; |
| 175 | |
| 176 | if (wait_event_interruptible(pipe->rx_wait_q, pipe->rx_maybe_avail)) |
| 177 | return -ERESTARTSYS; |
| 178 | |
| 179 | if (mutex_lock_interruptible(&pipe->pipe_mutex)) |
| 180 | return -ERESTARTSYS; |
| 181 | |
| 182 | /* Receive buffered data first */ |
| 183 | if (pipe->rx_buf_count) { |
| 184 | recv = min(pipe->rx_buf_count, count); |
| 185 | |
| 186 | if (copy_to_user(buf, pipe->rx_buf, recv)) { |
| 187 | mutex_unlock(&pipe->pipe_mutex); |
| 188 | return -EFAULT; |
| 189 | } |
| 190 | |
| 191 | pipe->rx_buf_count -= recv; |
| 192 | |
| 193 | if (pipe->rx_buf_count) { |
| 194 | memmove(pipe->rx_buf, pipe->rx_buf + recv, |
| 195 | pipe->max_msg_size - recv); |
| 196 | } |
| 197 | |
| 198 | buf += recv; |
| 199 | count -= recv; |
| 200 | if (!count) { |
| 201 | mutex_unlock(&pipe->pipe_mutex); |
| 202 | return recv; |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | buffer = kmalloc(pipe->max_msg_size + sizeof(uint32_t), GFP_KERNEL); |
| 207 | |
| 208 | if (!buffer) { |
| 209 | mutex_unlock(&pipe->pipe_mutex); |
| 210 | return -ENOMEM; |
| 211 | } |
| 212 | |
| 213 | while (count) { |
| 214 | okl4_error_t ret; |
| 215 | size_t size; |
| 216 | |
| 217 | spin_lock_irq(&pipe->pipe_lock); |
| 218 | recv_return = _okl4_sys_pipe_recv(pipe->pipe_rx_kcap, |
| 219 | pipe->max_msg_size + sizeof(uint32_t), |
| 220 | (void *)buffer); |
| 221 | ret = recv_return.error; |
| 222 | |
| 223 | if (ret == OKL4_ERROR_PIPE_NOT_READY || |
| 224 | ret == OKL4_ERROR_PIPE_EMPTY) { |
| 225 | pipe->rx_maybe_avail = false; |
| 226 | if (!recv) { |
| 227 | if (!(filp->f_flags & O_NONBLOCK)) { |
| 228 | spin_unlock_irq(&pipe->pipe_lock); |
| 229 | mutex_unlock(&pipe->pipe_mutex); |
| 230 | kfree(buffer); |
| 231 | goto again; |
| 232 | } |
| 233 | recv = -EAGAIN; |
| 234 | } |
| 235 | goto error; |
| 236 | } else if (ret != OKL4_OK) { |
| 237 | dev_err(&pipe->pdev->dev, |
| 238 | "pipe send returned error %d in okl4_pipe driver!\n", |
| 239 | (int)ret); |
| 240 | if (!recv) |
| 241 | recv = -ENXIO; |
| 242 | goto error; |
| 243 | } |
| 244 | |
| 245 | spin_unlock_irq(&pipe->pipe_lock); |
| 246 | |
| 247 | size = buffer[0]; |
| 248 | if (size > pipe->max_msg_size) { |
| 249 | /* pipe error */ |
| 250 | if (!recv) |
| 251 | recv = -EPROTO; |
| 252 | goto out; |
| 253 | } |
| 254 | |
| 255 | /* Save extra received data */ |
| 256 | if (size > count) { |
| 257 | pipe->rx_buf_count = size - count; |
| 258 | memcpy(pipe->rx_buf, (char*)&buffer[1] + count, |
| 259 | size - count); |
| 260 | size = count; |
| 261 | } |
| 262 | |
| 263 | if (copy_to_user(buf, &buffer[1], size)) { |
| 264 | if (!recv) |
| 265 | recv = -EFAULT; |
| 266 | goto out; |
| 267 | } |
| 268 | |
| 269 | |
| 270 | count -= size; |
| 271 | buf += size; |
| 272 | recv += size; |
| 273 | } |
| 274 | out: |
| 275 | mutex_unlock(&pipe->pipe_mutex); |
| 276 | |
| 277 | kfree(buffer); |
| 278 | return recv; |
| 279 | error: |
| 280 | spin_unlock_irq(&pipe->pipe_lock); |
| 281 | goto out; |
| 282 | } |
| 283 | |
| 284 | static ssize_t |
| 285 | okl4_pipe_write(struct file *filp, const char __user *buf, size_t count, |
| 286 | loff_t *f_pos) |
| 287 | { |
| 288 | struct okl4_pipe_mv *priv = filp->private_data; |
| 289 | int pipe_id = priv->pipe_id; |
| 290 | struct okl4_pipe *pipe = &pipes[pipe_id]; |
| 291 | uint32_t *buffer = NULL; |
| 292 | size_t sent = 0; |
| 293 | |
| 294 | if (!count) |
| 295 | return 0; |
| 296 | |
| 297 | again: |
| 298 | if (pipe->reset) |
| 299 | return -EPIPE; |
| 300 | |
| 301 | if (!pipe->tx_maybe_avail && (filp->f_flags & O_NONBLOCK)) |
| 302 | return -EAGAIN; |
| 303 | |
| 304 | if (wait_event_interruptible(pipe->tx_wait_q, pipe->tx_maybe_avail)) |
| 305 | return -ERESTARTSYS; |
| 306 | |
| 307 | if (mutex_lock_interruptible(&pipe->pipe_mutex)) |
| 308 | return -ERESTARTSYS; |
| 309 | |
| 310 | buffer = kmalloc(pipe->max_msg_size + sizeof(uint32_t), GFP_KERNEL); |
| 311 | |
| 312 | if (!buffer) { |
| 313 | mutex_unlock(&pipe->pipe_mutex); |
| 314 | return -ENOMEM; |
| 315 | } |
| 316 | |
| 317 | while (count) { |
| 318 | okl4_error_t ret; |
| 319 | size_t size = min(count, pipe->max_msg_size); |
| 320 | size_t pipe_size = roundup(size + sizeof(uint32_t), |
| 321 | sizeof(uint32_t)); |
| 322 | |
| 323 | if (copy_from_user(&buffer[1], buf, size)) { |
| 324 | if (!sent) |
| 325 | sent = -EFAULT; |
| 326 | break; |
| 327 | } |
| 328 | |
| 329 | buffer[0] = size; |
| 330 | |
| 331 | spin_lock_irq(&pipe->pipe_lock); |
| 332 | ret = _okl4_sys_pipe_send(pipe->pipe_tx_kcap, pipe_size, |
| 333 | (void *)buffer); |
| 334 | if (ret == OKL4_ERROR_PIPE_NOT_READY || |
| 335 | ret == OKL4_ERROR_PIPE_FULL) { |
| 336 | pipe->tx_maybe_avail = false; |
| 337 | spin_unlock_irq(&pipe->pipe_lock); |
| 338 | if (!sent) { |
| 339 | if (filp->f_flags & O_NONBLOCK) { |
| 340 | sent = -EAGAIN; |
| 341 | break; |
| 342 | } |
| 343 | mutex_unlock(&pipe->pipe_mutex); |
| 344 | kfree(buffer); |
| 345 | goto again; |
| 346 | } |
| 347 | break; |
| 348 | } else if (ret != OKL4_OK) { |
| 349 | dev_err(&pipe->pdev->dev, |
| 350 | "pipe send returned error %d in okl4_pipe driver!\n", |
| 351 | (int)ret); |
| 352 | if (!sent) |
| 353 | sent = -ENXIO; |
| 354 | spin_unlock_irq(&pipe->pipe_lock); |
| 355 | break; |
| 356 | } |
| 357 | spin_unlock_irq(&pipe->pipe_lock); |
| 358 | |
| 359 | count -= size; |
| 360 | buf += size; |
| 361 | sent += size; |
| 362 | } |
| 363 | mutex_unlock(&pipe->pipe_mutex); |
| 364 | |
| 365 | kfree(buffer); |
| 366 | return sent; |
| 367 | } |
| 368 | |
| 369 | |
| 370 | static unsigned int |
| 371 | okl4_pipe_poll(struct file *filp, struct poll_table_struct *poll_table) |
| 372 | { |
| 373 | struct okl4_pipe_mv *priv = filp->private_data; |
| 374 | int pipe_id = priv->pipe_id; |
| 375 | struct okl4_pipe *pipe = &pipes[pipe_id]; |
| 376 | unsigned int ret = 0; |
| 377 | |
| 378 | poll_wait(filp, &pipe->poll_wait_q, poll_table); |
| 379 | |
| 380 | spin_lock_irq(&pipe->pipe_lock); |
| 381 | |
| 382 | if (pipe->rx_maybe_avail) |
| 383 | ret |= POLLIN | POLLRDNORM; |
| 384 | if (pipe->tx_maybe_avail) |
| 385 | ret |= POLLOUT | POLLWRNORM; |
| 386 | if (pipe->reset) |
| 387 | ret = POLLHUP; |
| 388 | |
| 389 | spin_unlock_irq(&pipe->pipe_lock); |
| 390 | |
| 391 | return ret; |
| 392 | } |
| 393 | |
| 394 | static int |
| 395 | okl4_pipe_open(struct inode *inode, struct file *filp) |
| 396 | { |
| 397 | struct okl4_pipe *pipe = container_of(inode->i_cdev, |
| 398 | struct okl4_pipe, cdev); |
| 399 | struct okl4_pipe_mv *priv = dev_get_drvdata(&pipe->pdev->dev); |
| 400 | |
| 401 | filp->private_data = priv; |
| 402 | if (!pipe->ref_count) { |
| 403 | pipe->rx_buf = kmalloc(pipe->max_msg_size, GFP_KERNEL); |
| 404 | if (!pipe->rx_buf) |
| 405 | return -ENOMEM; |
| 406 | |
| 407 | mutex_init(&pipe->pipe_mutex); |
| 408 | spin_lock_init(&pipe->pipe_lock); |
| 409 | |
| 410 | pipe->rx_buf_count = 0; |
| 411 | pipe->reset = false; |
| 412 | pipe->tx_maybe_avail = true; |
| 413 | pipe->rx_maybe_avail = true; |
| 414 | |
| 415 | okl4_pipe_control(pipe->pipe_tx_kcap, |
| 416 | OKL4_PIPE_CONTROL_OP_SET_TX_READY); |
| 417 | okl4_pipe_control(pipe->pipe_rx_kcap, |
| 418 | OKL4_PIPE_CONTROL_OP_SET_RX_READY); |
| 419 | } |
| 420 | pipe->ref_count++; |
| 421 | return 0; |
| 422 | } |
| 423 | |
| 424 | static int |
| 425 | okl4_pipe_close(struct inode *inode, struct file *filp) |
| 426 | { |
| 427 | struct okl4_pipe *pipe = container_of(inode->i_cdev, |
| 428 | struct okl4_pipe, cdev); |
| 429 | |
| 430 | pipe->ref_count--; |
| 431 | if (!pipe->ref_count) { |
| 432 | okl4_pipe_control(pipe->pipe_rx_kcap, |
| 433 | OKL4_PIPE_CONTROL_OP_RESET); |
| 434 | okl4_pipe_control(pipe->pipe_tx_kcap, |
| 435 | OKL4_PIPE_CONTROL_OP_RESET); |
| 436 | |
| 437 | if (pipe->rx_buf) |
| 438 | kfree(pipe->rx_buf); |
| 439 | pipe->rx_buf = NULL; |
| 440 | pipe->rx_buf_count = 0; |
| 441 | } |
| 442 | |
| 443 | return 0; |
| 444 | } |
| 445 | |
| 446 | struct file_operations okl4_pipe_fops = { |
| 447 | .owner = THIS_MODULE, |
| 448 | .read = okl4_pipe_read, |
| 449 | .write = okl4_pipe_write, |
| 450 | .open = okl4_pipe_open, |
| 451 | .release = okl4_pipe_close, |
| 452 | .poll = okl4_pipe_poll, |
| 453 | }; |
| 454 | |
| 455 | static int __devinit |
| 456 | okl4_pipe_probe(struct platform_device *pdev) |
| 457 | { |
| 458 | struct okl4_pipe *pipe; |
| 459 | int err, pipe_id; |
| 460 | struct okl4_pipe_mv *priv; |
| 461 | dev_t dev_num; |
| 462 | struct device *device = NULL; |
| 463 | u32 reg[2]; |
| 464 | struct resource *irq; |
| 465 | |
| 466 | priv = devm_kzalloc(&pdev->dev, sizeof(struct okl4_pipe_mv), |
| 467 | GFP_KERNEL); |
| 468 | if (priv == NULL) { |
| 469 | err = -ENOMEM; |
| 470 | goto fail_alloc_priv; |
| 471 | } |
| 472 | |
| 473 | dev_set_drvdata(&pdev->dev, priv); |
| 474 | |
| 475 | pipe_id = of_alias_get_id(pdev->dev.of_node, "pipe"); |
| 476 | if (pipe_id < 0) { |
| 477 | err = -ENXIO; |
| 478 | goto fail_pipe_id; |
| 479 | } |
| 480 | |
| 481 | if (pipe_id < 0 || pipe_id >= MAX_PIPES) { |
| 482 | err = -ENXIO; |
| 483 | goto fail_pipe_id; |
| 484 | } |
| 485 | |
| 486 | if (of_property_read_u32_array(pdev->dev.of_node, "reg", reg, 2)) { |
| 487 | dev_err(&pdev->dev, "need 2 reg resources\n"); |
| 488 | err = -ENODEV; |
| 489 | goto fail_pipe_id; |
| 490 | } |
| 491 | |
| 492 | /* Populate the private structure */ |
| 493 | priv->pipe_id = pipe_id; |
| 494 | |
| 495 | pipe = &pipes[pipe_id]; |
| 496 | |
| 497 | /* Set up and register the pipe device */ |
| 498 | pipe->pdev = pdev; |
| 499 | dev_set_name(&pdev->dev, "%s%d", DEVICE_NAME, (int)pipe_id); |
| 500 | |
| 501 | pipe->ref_count = 0; |
| 502 | pipe->pipe_tx_kcap = reg[0]; |
| 503 | pipe->pipe_rx_kcap = reg[1]; |
| 504 | pipe->max_msg_size = 64; |
| 505 | |
| 506 | irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); |
| 507 | if (!irq) { |
| 508 | dev_err(&pdev->dev, "no tx irq resource?\n"); |
| 509 | err = -ENODEV; |
| 510 | goto fail_irq_resource; |
| 511 | } |
| 512 | pipe->tx_irq = irq->start; |
| 513 | irq = platform_get_resource(pdev, IORESOURCE_IRQ, 1); |
| 514 | if (!irq) { |
| 515 | dev_err(&pdev->dev, "no rx irq resource?\n"); |
| 516 | err = -ENODEV; |
| 517 | goto fail_irq_resource; |
| 518 | } |
| 519 | pipe->rx_irq = irq->start; |
| 520 | |
| 521 | pipe->write_buf = kmalloc(sizeof(pipe->write_buf), GFP_KERNEL); |
| 522 | if (!pipe->write_buf) { |
| 523 | dev_err(&pdev->dev, "cannot allocate write buffer\n"); |
| 524 | err = -ENOMEM; |
| 525 | goto fail_malloc_write; |
| 526 | } |
| 527 | |
| 528 | init_waitqueue_head(&pipe->rx_wait_q); |
| 529 | init_waitqueue_head(&pipe->tx_wait_q); |
| 530 | init_waitqueue_head(&pipe->poll_wait_q); |
| 531 | |
| 532 | err = devm_request_irq(&pdev->dev, pipe->rx_irq, |
| 533 | okl4_pipe_rx_irq, 0, dev_name(&pdev->dev), |
| 534 | pipe); |
| 535 | if (err) { |
| 536 | dev_err(&pdev->dev, "cannot register rx irq %d: %d\n", |
| 537 | (int)pipe->rx_irq, (int)err); |
| 538 | goto fail_request_rx_irq; |
| 539 | } |
| 540 | |
| 541 | err = devm_request_irq(&pdev->dev, pipe->tx_irq, |
| 542 | okl4_pipe_tx_irq, 0, dev_name(&pdev->dev), |
| 543 | pipe); |
| 544 | if (err) { |
| 545 | dev_err(&pdev->dev, "cannot register tx irq %d: %d\n", |
| 546 | (int)pipe->tx_irq, (int)err); |
| 547 | goto fail_request_tx_irq; |
| 548 | } |
| 549 | |
| 550 | dev_num = MKDEV(okl4_pipe_major, pipe_id); |
| 551 | |
| 552 | cdev_init(&pipe->cdev, &okl4_pipe_fops); |
| 553 | pipe->cdev.owner = THIS_MODULE; |
| 554 | err = cdev_add(&pipe->cdev, dev_num, 1); |
| 555 | if (err) { |
| 556 | dev_err(&pdev->dev, "cannot add device: %d\n", (int)err); |
| 557 | goto fail_cdev_add; |
| 558 | } |
| 559 | |
| 560 | device = device_create(okl4_pipe_class, NULL, dev_num, NULL, |
| 561 | DEVICE_NAME "%d", pipe_id); |
| 562 | if (IS_ERR(device)) { |
| 563 | err = PTR_ERR(device); |
| 564 | dev_err(&pdev->dev, "cannot create device: %d\n", (int)err); |
| 565 | goto fail_device_create; |
| 566 | } |
| 567 | |
| 568 | return 0; |
| 569 | |
| 570 | fail_device_create: |
| 571 | cdev_del(&pipe->cdev); |
| 572 | fail_cdev_add: |
| 573 | devm_free_irq(&pdev->dev, pipe->tx_irq, pipe); |
| 574 | fail_request_tx_irq: |
| 575 | devm_free_irq(&pdev->dev, pipe->rx_irq, pipe); |
| 576 | fail_request_rx_irq: |
| 577 | kfree(pipe->write_buf); |
| 578 | fail_malloc_write: |
| 579 | fail_irq_resource: |
| 580 | fail_pipe_id: |
| 581 | dev_set_drvdata(&pdev->dev, NULL); |
| 582 | devm_kfree(&pdev->dev, priv); |
| 583 | fail_alloc_priv: |
| 584 | return err; |
| 585 | } |
| 586 | |
| 587 | static int __devexit |
| 588 | okl4_pipe_remove(struct platform_device *pdev) |
| 589 | { |
| 590 | struct okl4_pipe *pipe; |
| 591 | struct okl4_pipe_mv *priv = dev_get_drvdata(&pdev->dev); |
| 592 | |
| 593 | if (priv->pipe_id < 0 || priv->pipe_id >= MAX_PIPES) |
| 594 | return -ENXIO; |
| 595 | |
| 596 | pipe = &pipes[priv->pipe_id]; |
| 597 | |
| 598 | cdev_del(&pipe->cdev); |
| 599 | |
| 600 | devm_free_irq(&pdev->dev, pipe->tx_irq, pipe); |
| 601 | devm_free_irq(&pdev->dev, pipe->rx_irq, pipe); |
| 602 | |
| 603 | kfree(pipe->write_buf); |
| 604 | |
| 605 | dev_set_drvdata(&pdev->dev, NULL); |
| 606 | devm_kfree(&pdev->dev, priv); |
| 607 | |
| 608 | return 0; |
| 609 | } |
| 610 | |
| 611 | static const struct of_device_id okl4_pipe_match[] = { |
| 612 | { |
| 613 | .compatible = "okl,pipe", |
| 614 | }, |
| 615 | {}, |
| 616 | }; |
| 617 | MODULE_DEVICE_TABLE(of, okl4_pipe_match); |
| 618 | |
| 619 | static struct platform_driver okl4_pipe_driver = { |
| 620 | .probe = okl4_pipe_probe, |
| 621 | .remove = __devexit_p(okl4_pipe_remove), |
| 622 | .driver = { |
| 623 | .name = DRIVER_NAME, |
| 624 | .owner = THIS_MODULE, |
| 625 | .of_match_table = okl4_pipe_match, |
| 626 | }, |
| 627 | }; |
| 628 | |
| 629 | static int __init |
| 630 | okl4_pipe_init(void) |
| 631 | { |
| 632 | int err; |
| 633 | dev_t dev_num = 0; |
| 634 | |
| 635 | err = alloc_chrdev_region(&dev_num, 0, MAX_PIPES, DEVICE_NAME); |
| 636 | if (err < 0) { |
| 637 | printk("%s: cannot allocate device region\n", __func__); |
| 638 | goto fail_alloc_chrdev_region; |
| 639 | } |
| 640 | okl4_pipe_major = MAJOR(dev_num); |
| 641 | |
| 642 | okl4_pipe_class = class_create(THIS_MODULE, DEVICE_NAME); |
| 643 | if (IS_ERR(okl4_pipe_class)) { |
| 644 | err = PTR_ERR(okl4_pipe_class); |
| 645 | goto fail_class_create; |
| 646 | } |
| 647 | |
| 648 | /* Register the driver with the microvisor bus */ |
| 649 | err = platform_driver_register(&okl4_pipe_driver); |
| 650 | if (err) |
| 651 | goto fail_driver_register; |
| 652 | |
| 653 | return 0; |
| 654 | |
| 655 | fail_driver_register: |
| 656 | class_destroy(okl4_pipe_class); |
| 657 | fail_class_create: |
| 658 | unregister_chrdev_region(dev_num, MAX_PIPES); |
| 659 | fail_alloc_chrdev_region: |
| 660 | return err; |
| 661 | } |
| 662 | |
| 663 | static void __exit |
| 664 | okl4_pipe_exit(void) |
| 665 | { |
| 666 | dev_t dev_num = MKDEV(okl4_pipe_major, 0); |
| 667 | |
| 668 | platform_driver_unregister(&okl4_pipe_driver); |
| 669 | class_destroy(okl4_pipe_class); |
| 670 | unregister_chrdev_region(dev_num, MAX_PIPES); |
| 671 | } |
| 672 | |
| 673 | module_init(okl4_pipe_init); |
| 674 | module_exit(okl4_pipe_exit); |
| 675 | |
| 676 | MODULE_DESCRIPTION("OKL4 pipe driver"); |
| 677 | MODULE_AUTHOR("John Clarke <johnc@cog.systems>"); |