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>
18 #include "kernel_ver.h"
20 /* Memory sizes for the buffers sent to/from the ES1 controller */
21 #define ES1_SVC_MSG_SIZE (sizeof(struct svc_msg) + SZ_64K)
22 #define ES1_GBUF_MSG_SIZE_MAX 2048
24 static const struct usb_device_id id_table[] = {
25 /* Made up numbers for the SVC USB Bridge in ES2 */
26 { USB_DEVICE(0xffff, 0x0002) },
29 MODULE_DEVICE_TABLE(usb, id_table);
31 #define APB1_LOG_SIZE SZ_16K
32 static struct dentry *apb1_log_dentry;
33 static struct dentry *apb1_log_enable_dentry;
34 static struct task_struct *apb1_log_task;
35 static DEFINE_KFIFO(apb1_log_fifo, char, APB1_LOG_SIZE);
37 /* Number of cport present on USB bridge */
40 /* Number of bulk in and bulk out couple */
44 * Number of CPort IN urbs in flight at any point in time.
45 * Adjust if we are having stalls in the USB buffer due to not enough urbs in
48 #define NUM_CPORT_IN_URB 4
50 /* Number of CPort OUT urbs in flight at any point in time.
51 * Adjust if we get messages saying we are out of urbs in the system log.
53 #define NUM_CPORT_OUT_URB (8 * NUM_BULKS)
55 /* vendor request AP message */
56 #define REQUEST_SVC 0x01
58 /* vendor request APB1 log */
59 #define REQUEST_LOG 0x02
61 /* vendor request to map a cport to bulk in and bulk out endpoints */
62 #define REQUEST_EP_MAPPING 0x03
65 * @endpoint: bulk in endpoint for CPort data
66 * @urb: array of urbs for the CPort in messages
67 * @buffer: array of buffers for the @cport_in_urb urbs
71 struct urb *urb[NUM_CPORT_IN_URB];
72 u8 *buffer[NUM_CPORT_IN_URB];
76 * @endpoint: bulk out endpoint for CPort data
78 struct es1_cport_out {
83 * es1_ap_dev - ES1 USB Bridge to AP structure
84 * @usb_dev: pointer to the USB device we are.
85 * @usb_intf: pointer to the USB interface we are bound to.
86 * @hd: pointer to our greybus_host_device structure
87 * @control_endpoint: endpoint to send data to SVC
88 * @svc_endpoint: endpoint for SVC data in
90 * @svc_buffer: buffer for SVC messages coming in on @svc_endpoint
91 * @svc_urb: urb for SVC messages coming in on @svc_endpoint
92 * @cport_in: endpoint, urbs and buffer for cport in messages
93 * @cport_out: endpoint for for cport out messages
94 * @cport_out_urb: array of urbs for the CPort out messages
95 * @cport_out_urb_busy: array of flags to see if the @cport_out_urb is busy or
97 * @cport_out_urb_lock: locks the @cport_out_urb_busy "list"
100 struct usb_device *usb_dev;
101 struct usb_interface *usb_intf;
102 struct greybus_host_device *hd;
104 __u8 control_endpoint;
110 struct es1_cport_in cport_in[NUM_BULKS];
111 struct es1_cport_out cport_out[NUM_BULKS];
112 struct urb *cport_out_urb[NUM_CPORT_OUT_URB];
113 bool cport_out_urb_busy[NUM_CPORT_OUT_URB];
114 spinlock_t cport_out_urb_lock;
116 int cport_to_ep[CPORT_MAX];
125 static inline struct es1_ap_dev *hd_to_es1(struct greybus_host_device *hd)
127 return (struct es1_ap_dev *)&hd->hd_priv;
130 static void cport_out_callback(struct urb *urb);
131 static void usb_log_enable(struct es1_ap_dev *es1);
132 static void usb_log_disable(struct es1_ap_dev *es1);
134 static int cport_to_ep(struct es1_ap_dev *es1, u16 cport_id)
136 if (cport_id >= CPORT_MAX)
138 return es1->cport_to_ep[cport_id];
141 #define ES1_TIMEOUT 500 /* 500 ms for the SVC to do something */
142 static int submit_svc(struct svc_msg *svc_msg, struct greybus_host_device *hd)
144 struct es1_ap_dev *es1 = hd_to_es1(hd);
147 /* SVC messages go down our control pipe */
148 retval = usb_control_msg(es1->usb_dev,
149 usb_sndctrlpipe(es1->usb_dev,
150 es1->control_endpoint),
152 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
157 if (retval != sizeof(*svc_msg))
163 static int ep_in_use(struct es1_ap_dev *es1, int bulk_ep_set)
167 for (i = 0; i < CPORT_MAX; i++) {
168 if (es1->cport_to_ep[i] == bulk_ep_set)
174 int map_cport_to_ep(struct es1_ap_dev *es1,
175 u16 cport_id, int bulk_ep_set)
178 struct cport_to_ep *cport_to_ep;
180 if (bulk_ep_set == 0 || bulk_ep_set >= NUM_BULKS)
182 if (cport_id >= CPORT_MAX)
184 if (bulk_ep_set && ep_in_use(es1, bulk_ep_set))
187 cport_to_ep = kmalloc(sizeof(*cport_to_ep), GFP_KERNEL);
191 es1->cport_to_ep[cport_id] = bulk_ep_set;
192 cport_to_ep->cport_id = cpu_to_le16(cport_id);
193 cport_to_ep->endpoint_in = es1->cport_in[bulk_ep_set].endpoint;
194 cport_to_ep->endpoint_out = es1->cport_out[bulk_ep_set].endpoint;
196 retval = usb_control_msg(es1->usb_dev,
197 usb_sndctrlpipe(es1->usb_dev,
198 es1->control_endpoint),
200 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
203 sizeof(*cport_to_ep),
205 if (retval == sizeof(*cport_to_ep))
212 int unmap_cport(struct es1_ap_dev *es1, u16 cport_id)
214 return map_cport_to_ep(es1, cport_id, 0);
217 static struct urb *next_free_urb(struct es1_ap_dev *es1, gfp_t gfp_mask)
219 struct urb *urb = NULL;
223 spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
225 /* Look in our pool of allocated urbs first, as that's the "fastest" */
226 for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
227 if (es1->cport_out_urb_busy[i] == false) {
228 es1->cport_out_urb_busy[i] = true;
229 urb = es1->cport_out_urb[i];
233 spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
238 * Crap, pool is empty, complain to the syslog and go allocate one
239 * dynamically as we have to succeed.
241 dev_err(&es1->usb_dev->dev,
242 "No free CPort OUT urbs, having to dynamically allocate one!\n");
243 return usb_alloc_urb(0, gfp_mask);
246 static void free_urb(struct es1_ap_dev *es1, struct urb *urb)
251 * See if this was an urb in our pool, if so mark it "free", otherwise
252 * we need to free it ourselves.
254 spin_lock_irqsave(&es1->cport_out_urb_lock, flags);
255 for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
256 if (urb == es1->cport_out_urb[i]) {
257 es1->cport_out_urb_busy[i] = false;
262 spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags);
264 /* If urb is not NULL, then we need to free this urb */
269 * Returns an opaque cookie value if successful, or a pointer coded
270 * error otherwise. If the caller wishes to cancel the in-flight
271 * buffer, it must supply the returned cookie to the cancel routine.
273 static void *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;
284 buffer = message->buffer;
285 buffer_size = sizeof(*message->header) + message->payload_size;
288 * The data actually transferred will include an indication
289 * of where the data should be sent. Do one last check of
290 * the target CPort id before filling it in.
292 if (cport_id == CPORT_ID_BAD) {
293 pr_err("request to send inbound data buffer\n");
294 return ERR_PTR(-EINVAL);
297 /* Find a free urb */
298 urb = next_free_urb(es1, gfp_mask);
300 return ERR_PTR(-ENOMEM);
303 * We (ab)use the operation-message header pad bytes to transfer the
304 * cport id in order to minimise overhead.
306 put_unaligned_le16(cport_id, message->header->pad);
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),
313 cport_out_callback, message);
314 retval = usb_submit_urb(urb, gfp_mask);
316 pr_err("error %d submitting URB\n", retval);
318 put_unaligned_le16(0, message->header->pad);
319 return ERR_PTR(retval);
326 * The cookie value supplied is the value that message_send()
327 * returned to its caller. It identifies the message that should be
328 * canceled. This function must also handle (which is to say,
329 * ignore) a null cookie value.
331 static void message_cancel(void *cookie)
335 * We really should be defensive and track all outstanding
336 * (sent) messages rather than trusting the cookie provided
337 * is valid. For the time being, this will do.
340 usb_kill_urb(cookie);
343 static struct greybus_host_driver es1_driver = {
344 .hd_priv_size = sizeof(struct es1_ap_dev),
345 .message_send = message_send,
346 .message_cancel = message_cancel,
347 .submit_svc = submit_svc,
350 /* Common function to report consistent warnings based on URB status */
351 static int check_urb_status(struct urb *urb)
353 struct device *dev = &urb->dev->dev;
354 int status = urb->status;
361 dev_err(dev, "%s: overflow actual length is %d\n",
362 __func__, urb->actual_length);
368 /* device is gone, stop sending */
371 dev_err(dev, "%s: unknown status %d\n", __func__, status);
376 static void ap_disconnect(struct usb_interface *interface)
378 struct es1_ap_dev *es1;
379 struct usb_device *udev;
383 es1 = usb_get_intfdata(interface);
387 usb_log_disable(es1);
389 /* Tear down everything! */
390 for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
391 struct urb *urb = es1->cport_out_urb[i];
397 es1->cport_out_urb[i] = NULL;
398 es1->cport_out_urb_busy[i] = false; /* just to be anal */
401 for (bulk_in = 0; bulk_in < NUM_BULKS; bulk_in++) {
402 struct es1_cport_in *cport_in = &es1->cport_in[bulk_in];
403 for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
404 struct urb *urb = cport_in->urb[i];
410 kfree(cport_in->buffer[i]);
411 cport_in->buffer[i] = NULL;
415 usb_kill_urb(es1->svc_urb);
416 usb_free_urb(es1->svc_urb);
418 kfree(es1->svc_buffer);
419 es1->svc_buffer = NULL;
421 usb_set_intfdata(interface, NULL);
423 greybus_remove_hd(es1->hd);
428 /* Callback for when we get a SVC message */
429 static void svc_in_callback(struct urb *urb)
431 struct greybus_host_device *hd = urb->context;
432 struct device *dev = &urb->dev->dev;
433 int status = check_urb_status(urb);
437 if ((status == -EAGAIN) || (status == -EPROTO))
439 dev_err(dev, "urb svc in error %d (dropped)\n", status);
443 /* We have a message, create a new message structure, add it to the
444 * list, and wake up our thread that will process the messages.
446 greybus_svc_in(hd, urb->transfer_buffer, urb->actual_length);
449 /* resubmit the urb to get more messages */
450 retval = usb_submit_urb(urb, GFP_ATOMIC);
452 dev_err(dev, "Can not submit urb for AP data: %d\n", retval);
455 static void cport_in_callback(struct urb *urb)
457 struct greybus_host_device *hd = urb->context;
458 struct device *dev = &urb->dev->dev;
459 struct gb_operation_msg_hdr *header;
460 int status = check_urb_status(urb);
465 if ((status == -EAGAIN) || (status == -EPROTO))
467 dev_err(dev, "urb cport in error %d (dropped)\n", status);
471 if (urb->actual_length < sizeof(*header)) {
472 dev_err(dev, "%s: short message received\n", __func__);
476 header = urb->transfer_buffer;
477 cport_id = get_unaligned_le16(header->pad);
478 put_unaligned_le16(0, header->pad);
480 greybus_data_rcvd(hd, cport_id, urb->transfer_buffer,
483 /* put our urb back in the request pool */
484 retval = usb_submit_urb(urb, GFP_ATOMIC);
486 dev_err(dev, "%s: error %d in submitting urb.\n",
490 static void cport_out_callback(struct urb *urb)
492 struct gb_message *message = urb->context;
493 struct greybus_host_device *hd = message->operation->connection->hd;
494 struct es1_ap_dev *es1 = hd_to_es1(hd);
495 int status = check_urb_status(urb);
497 /* Clear the pad bytes used for the cport id */
498 put_unaligned_le16(0, message->header->pad);
501 * Tell the submitter that the message send (attempt) is
502 * complete, and report the status.
504 greybus_message_sent(hd, message, status);
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;
650 bool int_in_found = false;
653 int retval = -ENOMEM;
655 u16 endo_id = 0x4755; // FIXME - get endo "ID" from the SVC
656 u8 ap_intf_id = 0x01; // FIXME - get endo "ID" from the SVC
659 udev = usb_get_dev(interface_to_usbdev(interface));
661 hd = greybus_create_hd(&es1_driver, &udev->dev, ES1_GBUF_MSG_SIZE_MAX);
669 es1->usb_intf = interface;
671 spin_lock_init(&es1->cport_out_urb_lock);
672 usb_set_intfdata(interface, es1);
674 /* Control endpoint is the pipe to talk to this AP, so save it off */
675 endpoint = &udev->ep0.desc;
676 es1->control_endpoint = endpoint->bEndpointAddress;
678 /* find all 3 of our endpoints */
679 iface_desc = interface->cur_altsetting;
680 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
681 endpoint = &iface_desc->endpoint[i].desc;
683 if (usb_endpoint_is_int_in(endpoint)) {
684 es1->svc_endpoint = endpoint->bEndpointAddress;
685 svc_interval = endpoint->bInterval;
687 } else if (usb_endpoint_is_bulk_in(endpoint)) {
688 es1->cport_in[bulk_in++].endpoint =
689 endpoint->bEndpointAddress;
690 } else if (usb_endpoint_is_bulk_out(endpoint)) {
691 es1->cport_out[bulk_out++].endpoint =
692 endpoint->bEndpointAddress;
695 "Unknown endpoint type found, address %x\n",
696 endpoint->bEndpointAddress);
699 if ((int_in_found == false) ||
702 dev_err(&udev->dev, "Not enough endpoints found in device, aborting!\n");
706 /* Create our buffer and URB to get SVC messages, and start it up */
707 es1->svc_buffer = kmalloc(ES1_SVC_MSG_SIZE, GFP_KERNEL);
708 if (!es1->svc_buffer)
711 es1->svc_urb = usb_alloc_urb(0, GFP_KERNEL);
715 usb_fill_int_urb(es1->svc_urb, udev,
716 usb_rcvintpipe(udev, es1->svc_endpoint),
717 es1->svc_buffer, ES1_SVC_MSG_SIZE, svc_in_callback,
720 /* Allocate buffers for our cport in messages and start them up */
721 for (bulk_in = 0; bulk_in < NUM_BULKS; bulk_in++) {
722 struct es1_cport_in *cport_in = &es1->cport_in[bulk_in];
723 for (i = 0; i < NUM_CPORT_IN_URB; ++i) {
727 urb = usb_alloc_urb(0, GFP_KERNEL);
730 buffer = kmalloc(ES1_GBUF_MSG_SIZE_MAX, GFP_KERNEL);
734 usb_fill_bulk_urb(urb, udev,
735 usb_rcvbulkpipe(udev,
737 buffer, ES1_GBUF_MSG_SIZE_MAX,
738 cport_in_callback, hd);
739 cport_in->urb[i] = urb;
740 cport_in->buffer[i] = buffer;
741 retval = usb_submit_urb(urb, GFP_KERNEL);
747 /* Allocate urbs for our CPort OUT messages */
748 for (i = 0; i < NUM_CPORT_OUT_URB; ++i) {
751 urb = usb_alloc_urb(0, GFP_KERNEL);
755 es1->cport_out_urb[i] = urb;
756 es1->cport_out_urb_busy[i] = false; /* just to be anal */
759 /* Start up our svc urb, which allows events to start flowing */
760 retval = usb_submit_urb(es1->svc_urb, GFP_KERNEL);
764 apb1_log_enable_dentry = debugfs_create_file("apb1_log_enable",
766 gb_debugfs_get(), es1,
767 &apb1_log_enable_fops);
770 * XXX Soon this will be initiated later, with a combination
771 * XXX of a Control protocol probe operation and a
772 * XXX subsequent Control protocol connected operation for
773 * XXX the SVC connection. At that point we know we're
774 * XXX properly connected to an Endo.
776 retval = greybus_endo_setup(hd, endo_id, ap_intf_id);
782 ap_disconnect(interface);
787 static struct usb_driver es1_ap_driver = {
788 .name = "es2_ap_driver",
790 .disconnect = ap_disconnect,
791 .id_table = id_table,
794 module_usb_driver(es1_ap_driver);
796 MODULE_LICENSE("GPL v2");
797 MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");