2 * Greybus "AP" USB driver for "ES2" controller chips
4 * Copyright 2014-2015 Google Inc.
5 * Copyright 2014-2015 Linaro Ltd.
7 * Released under the GPLv2 only.
9 #include <linux/kthread.h>
10 #include <linux/sizes.h>
11 #include <linux/usb.h>
12 #include <linux/kfifo.h>
13 #include <linux/debugfs.h>
14 #include <asm/unaligned.h>
17 #include "kernel_ver.h"
19 /* Memory sizes for the buffers sent to/from the ES1 controller */
20 #define ES1_GBUF_MSG_SIZE_MAX 2048
22 static const struct usb_device_id id_table[] = {
23 /* Made up numbers for the SVC USB Bridge in ES2 */
24 { USB_DEVICE(0xffff, 0x0002) },
27 MODULE_DEVICE_TABLE(usb, id_table);
29 #define APB1_LOG_SIZE SZ_16K
30 static struct dentry *apb1_log_dentry;
31 static struct dentry *apb1_log_enable_dentry;
32 static struct task_struct *apb1_log_task;
33 static DEFINE_KFIFO(apb1_log_fifo, char, APB1_LOG_SIZE);
35 /* Number of cport present on USB bridge */
38 /* Number of bulk in and bulk out couple */
42 * Number of CPort IN urbs in flight at any point in time.
43 * Adjust if we are having stalls in the USB buffer due to not enough urbs in
46 #define NUM_CPORT_IN_URB 4
48 /* Number of CPort OUT urbs in flight at any point in time.
49 * Adjust if we get messages saying we are out of urbs in the system log.
51 #define NUM_CPORT_OUT_URB (8 * NUM_BULKS)
53 /* vendor request AP message */
54 #define REQUEST_SVC 0x01
56 /* vendor request APB1 log */
57 #define REQUEST_LOG 0x02
59 /* vendor request to map a cport to bulk in and bulk out endpoints */
60 #define REQUEST_EP_MAPPING 0x03
63 * @endpoint: bulk in endpoint for CPort data
64 * @urb: array of urbs for the CPort in messages
65 * @buffer: array of buffers for the @cport_in_urb urbs
69 struct urb *urb[NUM_CPORT_IN_URB];
70 u8 *buffer[NUM_CPORT_IN_URB];
74 * @endpoint: bulk out endpoint for CPort data
76 struct es1_cport_out {
81 * es1_ap_dev - ES1 USB Bridge to AP structure
82 * @usb_dev: pointer to the USB device we are.
83 * @usb_intf: pointer to the USB interface we are bound to.
84 * @hd: pointer to our greybus_host_device structure
85 * @control_endpoint: endpoint to send data to SVC
87 * @cport_in: endpoint, urbs and buffer for cport in messages
88 * @cport_out: endpoint for for cport out messages
89 * @cport_out_urb: array of urbs for the CPort out messages
90 * @cport_out_urb_busy: array of flags to see if the @cport_out_urb is busy or
92 * @cport_out_urb_cancelled: array of flags indicating whether the
93 * corresponding @cport_out_urb is being cancelled
94 * @cport_out_urb_lock: locks the @cport_out_urb_busy "list"
97 struct usb_device *usb_dev;
98 struct usb_interface *usb_intf;
99 struct greybus_host_device *hd;
101 __u8 control_endpoint;
103 struct es1_cport_in cport_in[NUM_BULKS];
104 struct es1_cport_out cport_out[NUM_BULKS];
105 struct urb *cport_out_urb[NUM_CPORT_OUT_URB];
106 bool cport_out_urb_busy[NUM_CPORT_OUT_URB];
107 bool cport_out_urb_cancelled[NUM_CPORT_OUT_URB];
108 spinlock_t cport_out_urb_lock;
110 int cport_to_ep[CPORT_MAX];
119 static inline struct es1_ap_dev *hd_to_es1(struct greybus_host_device *hd)
121 return (struct es1_ap_dev *)&hd->hd_priv;
124 static void cport_out_callback(struct urb *urb);
125 static void usb_log_enable(struct es1_ap_dev *es1);
126 static void usb_log_disable(struct es1_ap_dev *es1);
128 static int cport_to_ep(struct es1_ap_dev *es1, u16 cport_id)
130 if (cport_id >= CPORT_MAX)
132 return es1->cport_to_ep[cport_id];
135 #define ES1_TIMEOUT 500 /* 500 ms for the SVC to do something */
137 static int ep_in_use(struct es1_ap_dev *es1, int bulk_ep_set)
141 for (i = 0; i < CPORT_MAX; i++) {
142 if (es1->cport_to_ep[i] == bulk_ep_set)
148 int map_cport_to_ep(struct es1_ap_dev *es1,
149 u16 cport_id, int bulk_ep_set)
152 struct cport_to_ep *cport_to_ep;
154 if (bulk_ep_set == 0 || bulk_ep_set >= NUM_BULKS)
156 if (cport_id >= CPORT_MAX)
158 if (bulk_ep_set && ep_in_use(es1, bulk_ep_set))
161 cport_to_ep = kmalloc(sizeof(*cport_to_ep), GFP_KERNEL);
165 es1->cport_to_ep[cport_id] = bulk_ep_set;
166 cport_to_ep->cport_id = cpu_to_le16(cport_id);
167 cport_to_ep->endpoint_in = es1->cport_in[bulk_ep_set].endpoint;
168 cport_to_ep->endpoint_out = es1->cport_out[bulk_ep_set].endpoint;
170 retval = usb_control_msg(es1->usb_dev,
171 usb_sndctrlpipe(es1->usb_dev,
172 es1->control_endpoint),
174 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
177 sizeof(*cport_to_ep),
179 if (retval == sizeof(*cport_to_ep))
186 int unmap_cport(struct es1_ap_dev *es1, u16 cport_id)
188 return map_cport_to_ep(es1, cport_id, 0);
191 static struct urb *next_free_urb(struct es1_ap_dev *es1, gfp_t gfp_mask)
193 struct urb *urb = NULL;
197 spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
199 /* Look in our pool of allocated urbs first, as that's the "fastest" */
200 for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
201 if (es1->cport_out_urb_busy[i] == false &&
202 es1->cport_out_urb_cancelled[i] == false) {
203 es1->cport_out_urb_busy[i] = true;
204 urb = es1->cport_out_urb[i];
208 spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
213 * Crap, pool is empty, complain to the syslog and go allocate one
214 * dynamically as we have to succeed.
216 dev_err(&es1->usb_dev->dev,
217 "No free CPort OUT urbs, having to dynamically allocate one!\n");
218 return usb_alloc_urb(0, gfp_mask);
221 static void free_urb(struct es1_ap_dev *es1, struct urb *urb)
226 * See if this was an urb in our pool, if so mark it "free", otherwise
227 * we need to free it ourselves.
229 spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
230 for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
231 if (urb == es1->cport_out_urb[i]) {
232 es1->cport_out_urb_busy[i] = false;
237 spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
239 /* If urb is not NULL, then we need to free this urb */
244 * We (ab)use the operation-message header pad bytes to transfer the
245 * cport id in order to minimise overhead.
248 gb_message_cport_pack(struct gb_operation_msg_hdr *header, u16 cport_id)
250 header->pad[0] = cport_id;
253 /* Clear the pad bytes used for the CPort id */
254 static void gb_message_cport_clear(struct gb_operation_msg_hdr *header)
259 /* Extract the CPort id packed into the header, and clear it */
260 static u16 gb_message_cport_unpack(struct gb_operation_msg_hdr *header)
262 u16 cport_id = header->pad[0];
264 gb_message_cport_clear(header);
270 * Returns zero if the message was successfully queued, or a negative errno
273 static int message_send(struct greybus_host_device *hd, u16 cport_id,
274 struct gb_message *message, gfp_t gfp_mask)
276 struct es1_ap_dev *es1 = hd_to_es1(hd);
277 struct usb_device *udev = es1->usb_dev;
285 * The data actually transferred will include an indication
286 * of where the data should be sent. Do one last check of
287 * the target CPort id before filling it in.
289 if (!cport_id_valid(cport_id)) {
290 pr_err("invalid destination cport 0x%02x\n", cport_id);
294 /* Find a free urb */
295 urb = next_free_urb(es1, gfp_mask);
299 spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
300 message->hcpriv = urb;
301 spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
303 /* Pack the cport id into the message header */
304 gb_message_cport_pack(message->header, cport_id);
306 buffer_size = sizeof(*message->header) + message->payload_size;
308 bulk_ep_set = cport_to_ep(es1, cport_id);
309 usb_fill_bulk_urb(urb, udev,
310 usb_sndbulkpipe(udev,
311 es1->cport_out[bulk_ep_set].endpoint),
312 message->buffer, buffer_size,
313 cport_out_callback, message);
314 retval = usb_submit_urb(urb, gfp_mask);
316 pr_err("error %d submitting URB\n", retval);
318 spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
319 message->hcpriv = NULL;
320 spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
323 gb_message_cport_clear(message->header);
332 * Can not be called in atomic context.
334 static void message_cancel(struct gb_message *message)
336 struct greybus_host_device *hd = message->operation->connection->hd;
337 struct es1_ap_dev *es1 = hd_to_es1(hd);
343 spin_lock_irq(&es1->cport_out_urb_lock);
344 urb = message->hcpriv;
346 /* Prevent dynamically allocated urb from being deallocated. */
349 /* Prevent pre-allocated urb from being reused. */
350 for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
351 if (urb == es1->cport_out_urb[i]) {
352 es1->cport_out_urb_cancelled[i] = true;
356 spin_unlock_irq(&es1->cport_out_urb_lock);
360 if (i < NUM_CPORT_OUT_URB) {
361 spin_lock_irq(&es1->cport_out_urb_lock);
362 es1->cport_out_urb_cancelled[i] = false;
363 spin_unlock_irq(&es1->cport_out_urb_lock);
369 static struct greybus_host_driver es1_driver = {
370 .hd_priv_size = sizeof(struct es1_ap_dev),
371 .message_send = message_send,
372 .message_cancel = message_cancel,
375 /* Common function to report consistent warnings based on URB status */
376 static int check_urb_status(struct urb *urb)
378 struct device *dev = &urb->dev->dev;
379 int status = urb->status;
386 dev_err(dev, "%s: overflow actual length is %d\n",
387 __func__, urb->actual_length);
393 /* device is gone, stop sending */
396 dev_err(dev, "%s: unknown status %d\n", __func__, status);
401 static void ap_disconnect(struct usb_interface *interface)
403 struct es1_ap_dev *es1;
404 struct usb_device *udev;
408 es1 = usb_get_intfdata(interface);
412 usb_log_disable(es1);
414 /* Tear down everything! */
415 for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
416 struct urb *urb = es1->cport_out_urb[i];
422 es1->cport_out_urb[i] = NULL;
423 es1->cport_out_urb_busy[i] = false; /* just to be anal */
426 for (bulk_in = 0; bulk_in < NUM_BULKS; bulk_in++) {
427 struct es1_cport_in *cport_in = &es1->cport_in[bulk_in];
428 for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
429 struct urb *urb = cport_in->urb[i];
435 kfree(cport_in->buffer[i]);
436 cport_in->buffer[i] = NULL;
440 usb_set_intfdata(interface, NULL);
442 greybus_remove_hd(es1->hd);
447 static void cport_in_callback(struct urb *urb)
449 struct greybus_host_device *hd = urb->context;
450 struct device *dev = &urb->dev->dev;
451 struct gb_operation_msg_hdr *header;
452 int status = check_urb_status(urb);
457 if ((status == -EAGAIN) || (status == -EPROTO))
459 dev_err(dev, "urb cport in error %d (dropped)\n", status);
463 if (urb->actual_length < sizeof(*header)) {
464 dev_err(dev, "%s: short message received\n", __func__);
468 /* Extract the CPort id, which is packed in the message header */
469 header = urb->transfer_buffer;
470 cport_id = gb_message_cport_unpack(header);
472 if (cport_id_valid(cport_id))
473 greybus_data_rcvd(hd, cport_id, urb->transfer_buffer,
476 dev_err(dev, "%s: invalid cport id 0x%02x received\n",
479 /* put our urb back in the request pool */
480 retval = usb_submit_urb(urb, GFP_ATOMIC);
482 dev_err(dev, "%s: error %d in submitting urb.\n",
486 static void cport_out_callback(struct urb *urb)
488 struct gb_message *message = urb->context;
489 struct greybus_host_device *hd = message->operation->connection->hd;
490 struct es1_ap_dev *es1 = hd_to_es1(hd);
491 int status = check_urb_status(urb);
494 gb_message_cport_clear(message->header);
497 * Tell the submitter that the message send (attempt) is
498 * complete, and report the status.
500 greybus_message_sent(hd, message, status);
502 spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
503 message->hcpriv = NULL;
504 spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
509 #define APB1_LOG_MSG_SIZE 64
510 static void apb1_log_get(struct es1_ap_dev *es1, char *buf)
514 /* SVC messages go down our control pipe */
516 retval = usb_control_msg(es1->usb_dev,
517 usb_rcvctrlpipe(es1->usb_dev,
518 es1->control_endpoint),
520 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
526 kfifo_in(&apb1_log_fifo, buf, retval);
527 } while (retval > 0);
530 static int apb1_log_poll(void *data)
532 struct es1_ap_dev *es1 = data;
535 buf = kmalloc(APB1_LOG_MSG_SIZE, GFP_KERNEL);
539 while (!kthread_should_stop()) {
541 apb1_log_get(es1, buf);
549 static ssize_t apb1_log_read(struct file *f, char __user *buf,
550 size_t count, loff_t *ppos)
556 if (count > APB1_LOG_SIZE)
557 count = APB1_LOG_SIZE;
559 tmp_buf = kmalloc(count, GFP_KERNEL);
563 copied = kfifo_out(&apb1_log_fifo, tmp_buf, count);
564 ret = simple_read_from_buffer(buf, count, ppos, tmp_buf, copied);
571 static const struct file_operations apb1_log_fops = {
572 .read = apb1_log_read,
575 static void usb_log_enable(struct es1_ap_dev *es1)
577 if (!IS_ERR_OR_NULL(apb1_log_task))
580 /* get log from APB1 */
581 apb1_log_task = kthread_run(apb1_log_poll, es1, "apb1_log");
582 if (IS_ERR(apb1_log_task))
584 apb1_log_dentry = debugfs_create_file("apb1_log", S_IRUGO,
585 gb_debugfs_get(), NULL,
589 static void usb_log_disable(struct es1_ap_dev *es1)
591 if (IS_ERR_OR_NULL(apb1_log_task))
594 debugfs_remove(apb1_log_dentry);
595 apb1_log_dentry = NULL;
597 kthread_stop(apb1_log_task);
598 apb1_log_task = NULL;
601 static ssize_t apb1_log_enable_read(struct file *f, char __user *buf,
602 size_t count, loff_t *ppos)
605 int enable = !IS_ERR_OR_NULL(apb1_log_task);
607 sprintf(tmp_buf, "%d\n", enable);
608 return simple_read_from_buffer(buf, count, ppos, tmp_buf, 3);
611 static ssize_t apb1_log_enable_write(struct file *f, const char __user *buf,
612 size_t count, loff_t *ppos)
616 struct es1_ap_dev *es1 = (struct es1_ap_dev *)f->f_inode->i_private;
618 retval = kstrtoint_from_user(buf, count, 10, &enable);
625 usb_log_disable(es1);
630 static const struct file_operations apb1_log_enable_fops = {
631 .read = apb1_log_enable_read,
632 .write = apb1_log_enable_write,
636 * The ES1 USB Bridge device contains 4 endpoints
637 * 1 Control - usual USB stuff + AP -> SVC messages
638 * 1 Interrupt IN - SVC -> AP messages
639 * 1 Bulk IN - CPort data in
640 * 1 Bulk OUT - CPort data out
642 static int ap_probe(struct usb_interface *interface,
643 const struct usb_device_id *id)
645 struct es1_ap_dev *es1;
646 struct greybus_host_device *hd;
647 struct usb_device *udev;
648 struct usb_host_interface *iface_desc;
649 struct usb_endpoint_descriptor *endpoint;
652 int retval = -ENOMEM;
655 /* We need to fit a CPort ID in one byte of a message header */
656 BUILD_BUG_ON(CPORT_ID_MAX > U8_MAX);
658 udev = usb_get_dev(interface_to_usbdev(interface));
660 hd = greybus_create_hd(&es1_driver, &udev->dev, ES1_GBUF_MSG_SIZE_MAX);
668 es1->usb_intf = interface;
670 spin_lock_init(&es1->cport_out_urb_lock);
671 usb_set_intfdata(interface, es1);
673 /* Control endpoint is the pipe to talk to this AP, so save it off */
674 endpoint = &udev->ep0.desc;
675 es1->control_endpoint = endpoint->bEndpointAddress;
677 /* find all 3 of our endpoints */
678 iface_desc = interface->cur_altsetting;
679 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
680 endpoint = &iface_desc->endpoint[i].desc;
682 if (usb_endpoint_is_bulk_in(endpoint)) {
683 es1->cport_in[bulk_in++].endpoint =
684 endpoint->bEndpointAddress;
685 } else if (usb_endpoint_is_bulk_out(endpoint)) {
686 es1->cport_out[bulk_out++].endpoint =
687 endpoint->bEndpointAddress;
690 "Unknown endpoint type found, address %x\n",
691 endpoint->bEndpointAddress);
694 if ((bulk_in == 0) ||
696 dev_err(&udev->dev, "Not enough endpoints found in device, aborting!\n");
700 /* Allocate buffers for our cport in messages and start them up */
701 for (bulk_in = 0; bulk_in < NUM_BULKS; bulk_in++) {
702 struct es1_cport_in *cport_in = &es1->cport_in[bulk_in];
703 for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
707 urb = usb_alloc_urb(0, GFP_KERNEL);
710 buffer = kmalloc(ES1_GBUF_MSG_SIZE_MAX, GFP_KERNEL);
714 usb_fill_bulk_urb(urb, udev,
715 usb_rcvbulkpipe(udev,
717 buffer, ES1_GBUF_MSG_SIZE_MAX,
718 cport_in_callback, hd);
719 cport_in->urb[i] = urb;
720 cport_in->buffer[i] = buffer;
721 retval = usb_submit_urb(urb, GFP_KERNEL);
727 /* Allocate urbs for our CPort OUT messages */
728 for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
731 urb = usb_alloc_urb(0, GFP_KERNEL);
735 es1->cport_out_urb[i] = urb;
736 es1->cport_out_urb_busy[i] = false; /* just to be anal */
739 apb1_log_enable_dentry = debugfs_create_file("apb1_log_enable",
741 gb_debugfs_get(), es1,
742 &apb1_log_enable_fops);
745 ap_disconnect(interface);
750 static struct usb_driver es1_ap_driver = {
751 .name = "es2_ap_driver",
753 .disconnect = ap_disconnect,
754 .id_table = id_table,
757 module_usb_driver(es1_ap_driver);
759 MODULE_LICENSE("GPL v2");
760 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");