/* * Greybus "AP" USB driver for "ES2" controller chips * * Copyright 2014-2015 Google Inc. * Copyright 2014-2015 Linaro Ltd. * * Released under the GPLv2 only. */ #include #include #include #include #include #include #include #include #include #include #include #include "greybus.h" #include "svc_msg.h" #include "kernel_ver.h" /* Memory sizes for the buffers sent to/from the ES1 controller */ #define ES1_SVC_MSG_SIZE (sizeof(struct svc_msg) + SZ_64K) #define ES1_GBUF_MSG_SIZE_MAX PAGE_SIZE static const struct usb_device_id id_table[] = { /* Made up numbers for the SVC USB Bridge in ES2 */ { USB_DEVICE(0xffff, 0x0002) }, { }, }; MODULE_DEVICE_TABLE(usb, id_table); #define APB1_LOG_SIZE SZ_16K static struct dentry *apb1_log_dentry; static struct dentry *apb1_log_enable_dentry; static struct task_struct *apb1_log_task; static DEFINE_KFIFO(apb1_log_fifo, char, APB1_LOG_SIZE); /* * Number of CPort IN urbs in flight at any point in time. * Adjust if we are having stalls in the USB buffer due to not enough urbs in * flight. */ #define NUM_CPORT_IN_URB 4 /* Number of CPort OUT urbs in flight at any point in time. * Adjust if we get messages saying we are out of urbs in the system log. */ #define NUM_CPORT_OUT_URB 8 /** * es1_ap_dev - ES1 USB Bridge to AP structure * @usb_dev: pointer to the USB device we are. * @usb_intf: pointer to the USB interface we are bound to. * @hd: pointer to our greybus_host_device structure * @control_endpoint: endpoint to send data to SVC * @svc_endpoint: endpoint for SVC data in * @cport_in_endpoint: bulk in endpoint for CPort data * @cport-out_endpoint: bulk out endpoint for CPort data * @svc_buffer: buffer for SVC messages coming in on @svc_endpoint * @svc_urb: urb for SVC messages coming in on @svc_endpoint * @cport_in_urb: array of urbs for the CPort in messages * @cport_in_buffer: array of buffers for the @cport_in_urb urbs * @cport_out_urb: array of urbs for the CPort out messages * @cport_out_urb_busy: array of flags to see if the @cport_out_urb is busy or * not. * @cport_out_urb_lock: locks the @cport_out_urb_busy "list" */ struct es1_ap_dev { struct usb_device *usb_dev; struct usb_interface *usb_intf; struct greybus_host_device *hd; __u8 control_endpoint; __u8 svc_endpoint; __u8 cport_in_endpoint; __u8 cport_out_endpoint; u8 *svc_buffer; struct urb *svc_urb; struct urb *cport_in_urb[NUM_CPORT_IN_URB]; u8 *cport_in_buffer[NUM_CPORT_IN_URB]; struct urb *cport_out_urb[NUM_CPORT_OUT_URB]; bool cport_out_urb_busy[NUM_CPORT_OUT_URB]; spinlock_t cport_out_urb_lock; }; static inline struct es1_ap_dev *hd_to_es1(struct greybus_host_device *hd) { return (struct es1_ap_dev *)&hd->hd_priv; } static void cport_out_callback(struct urb *urb); static void usb_log_enable(struct es1_ap_dev *es1); static void usb_log_disable(struct es1_ap_dev *es1); #define ES1_TIMEOUT 500 /* 500 ms for the SVC to do something */ static int submit_svc(struct svc_msg *svc_msg, struct greybus_host_device *hd) { struct es1_ap_dev *es1 = hd_to_es1(hd); int retval; /* SVC messages go down our control pipe */ retval = usb_control_msg(es1->usb_dev, usb_sndctrlpipe(es1->usb_dev, es1->control_endpoint), 0x01, /* vendor request AP message */ USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 0x00, 0x00, (char *)svc_msg, sizeof(*svc_msg), ES1_TIMEOUT); if (retval != sizeof(*svc_msg)) return retval; return 0; } static struct urb *next_free_urb(struct es1_ap_dev *es1, gfp_t gfp_mask) { struct urb *urb = NULL; unsigned long flags; int i; spin_lock_irqsave(&es1->cport_out_urb_lock, flags); /* Look in our pool of allocated urbs first, as that's the "fastest" */ for (i = 0; i < NUM_CPORT_OUT_URB; ++i) { if (es1->cport_out_urb_busy[i] == false) { es1->cport_out_urb_busy[i] = true; urb = es1->cport_out_urb[i]; break; } } spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags); if (urb) return urb; /* * Crap, pool is empty, complain to the syslog and go allocate one * dynamically as we have to succeed. */ dev_err(&es1->usb_dev->dev, "No free CPort OUT urbs, having to dynamically allocate one!\n"); return usb_alloc_urb(0, gfp_mask); } static void free_urb(struct es1_ap_dev *es1, struct urb *urb) { unsigned long flags; int i; /* * See if this was an urb in our pool, if so mark it "free", otherwise * we need to free it ourselves. */ spin_lock_irqsave(&es1->cport_out_urb_lock, flags); for (i = 0; i < NUM_CPORT_OUT_URB; ++i) { if (urb == es1->cport_out_urb[i]) { es1->cport_out_urb_busy[i] = false; urb = NULL; break; } } spin_unlock_irqrestore(&es1->cport_out_urb_lock, flags); /* If urb is not NULL, then we need to free this urb */ usb_free_urb(urb); } /* * Returns an opaque cookie value if successful, or a pointer coded * error otherwise. If the caller wishes to cancel the in-flight * buffer, it must supply the returned cookie to the cancel routine. */ static void *message_send(struct greybus_host_device *hd, u16 cport_id, struct gb_message *message, gfp_t gfp_mask) { struct es1_ap_dev *es1 = hd_to_es1(hd); struct usb_device *udev = es1->usb_dev; void *buffer; size_t buffer_size; int retval; struct urb *urb; buffer = message->buffer; buffer_size = sizeof(*message->header) + message->payload_size; /* * The data actually transferred will include an indication * of where the data should be sent. Do one last check of * the target CPort id before filling it in. */ if (cport_id == CPORT_ID_BAD) { pr_err("request to send inbound data buffer\n"); return ERR_PTR(-EINVAL); } /* Find a free urb */ urb = next_free_urb(es1, gfp_mask); if (!urb) return ERR_PTR(-ENOMEM); /* * We (ab)use the operation-message header pad bytes to transfer the * cport id in order to minimise overhead. */ put_unaligned_le16(cport_id, message->header->pad); usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, es1->cport_out_endpoint), buffer, buffer_size, cport_out_callback, message); retval = usb_submit_urb(urb, gfp_mask); if (retval) { pr_err("error %d submitting URB\n", retval); free_urb(es1, urb); put_unaligned_le16(0, message->header->pad); return ERR_PTR(retval); } return urb; } /* * The cookie value supplied is the value that message_send() * returned to its caller. It identifies the message that should be * canceled. This function must also handle (which is to say, * ignore) a null cookie value. */ static void message_cancel(void *cookie) { /* * We really should be defensive and track all outstanding * (sent) messages rather than trusting the cookie provided * is valid. For the time being, this will do. */ if (cookie) usb_kill_urb(cookie); } static struct greybus_host_driver es1_driver = { .hd_priv_size = sizeof(struct es1_ap_dev), .message_send = message_send, .message_cancel = message_cancel, .submit_svc = submit_svc, }; /* Common function to report consistent warnings based on URB status */ static int check_urb_status(struct urb *urb) { struct device *dev = &urb->dev->dev; int status = urb->status; switch (status) { case 0: return 0; case -EOVERFLOW: dev_err(dev, "%s: overflow actual length is %d\n", __func__, urb->actual_length); case -ECONNRESET: case -ENOENT: case -ESHUTDOWN: case -EILSEQ: case -EPROTO: /* device is gone, stop sending */ return status; } dev_err(dev, "%s: unknown status %d\n", __func__, status); return -EAGAIN; } static void ap_disconnect(struct usb_interface *interface) { struct es1_ap_dev *es1; struct usb_device *udev; int i; es1 = usb_get_intfdata(interface); if (!es1) return; usb_log_disable(es1); /* Tear down everything! */ for (i = 0; i < NUM_CPORT_OUT_URB; ++i) { struct urb *urb = es1->cport_out_urb[i]; if (!urb) break; usb_kill_urb(urb); usb_free_urb(urb); es1->cport_out_urb[i] = NULL; es1->cport_out_urb_busy[i] = false; /* just to be anal */ } for (i = 0; i < NUM_CPORT_IN_URB; ++i) { struct urb *urb = es1->cport_in_urb[i]; if (!urb) break; usb_kill_urb(urb); usb_free_urb(urb); kfree(es1->cport_in_buffer[i]); es1->cport_in_buffer[i] = NULL; } usb_kill_urb(es1->svc_urb); usb_free_urb(es1->svc_urb); es1->svc_urb = NULL; kfree(es1->svc_buffer); es1->svc_buffer = NULL; usb_set_intfdata(interface, NULL); udev = es1->usb_dev; greybus_remove_hd(es1->hd); usb_put_dev(udev); } /* Callback for when we get a SVC message */ static void svc_in_callback(struct urb *urb) { struct greybus_host_device *hd = urb->context; struct device *dev = &urb->dev->dev; int status = check_urb_status(urb); int retval; if (status) { if ((status == -EAGAIN) || (status == -EPROTO)) goto exit; dev_err(dev, "urb svc in error %d (dropped)\n", status); return; } /* We have a message, create a new message structure, add it to the * list, and wake up our thread that will process the messages. */ greybus_svc_in(hd, urb->transfer_buffer, urb->actual_length); exit: /* resubmit the urb to get more messages */ retval = usb_submit_urb(urb, GFP_ATOMIC); if (retval) dev_err(dev, "Can not submit urb for AP data: %d\n", retval); } static void cport_in_callback(struct urb *urb) { struct greybus_host_device *hd = urb->context; struct device *dev = &urb->dev->dev; struct gb_operation_msg_hdr *header; int status = check_urb_status(urb); int retval; u16 cport_id; if (status) { if ((status == -EAGAIN) || (status == -EPROTO)) goto exit; dev_err(dev, "urb cport in error %d (dropped)\n", status); return; } if (urb->actual_length < sizeof(*header)) { dev_err(dev, "%s: short message received\n", __func__); goto exit; } header = urb->transfer_buffer; cport_id = get_unaligned_le16(header->pad); put_unaligned_le16(0, header->pad); greybus_data_rcvd(hd, cport_id, urb->transfer_buffer, urb->actual_length); exit: /* put our urb back in the request pool */ retval = usb_submit_urb(urb, GFP_ATOMIC); if (retval) dev_err(dev, "%s: error %d in submitting urb.\n", __func__, retval); } static void cport_out_callback(struct urb *urb) { struct gb_message *message = urb->context; struct greybus_host_device *hd = message->operation->connection->hd; struct es1_ap_dev *es1 = hd_to_es1(hd); int status = check_urb_status(urb); /* Clear the pad bytes used for the cport id */ put_unaligned_le16(0, message->header->pad); /* * Tell the submitter that the message send (attempt) is * complete, and report the status. */ greybus_message_sent(hd, message, status); free_urb(es1, urb); } #define APB1_LOG_MSG_SIZE 64 static void apb1_log_get(struct es1_ap_dev *es1, char *buf) { int retval; /* SVC messages go down our control pipe */ do { retval = usb_control_msg(es1->usb_dev, usb_rcvctrlpipe(es1->usb_dev, es1->control_endpoint), 0x02, /* vendor request APB1 log */ USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 0x00, 0x00, buf, APB1_LOG_MSG_SIZE, ES1_TIMEOUT); if (retval > 0) kfifo_in(&apb1_log_fifo, buf, retval); } while (retval > 0); } static int apb1_log_poll(void *data) { struct es1_ap_dev *es1 = data; char *buf; buf = kmalloc(APB1_LOG_MSG_SIZE, GFP_KERNEL); if (!buf) return -ENOMEM; while (!kthread_should_stop()) { msleep(1000); apb1_log_get(es1, buf); } kfree(buf); return 0; } static ssize_t apb1_log_read(struct file *f, char __user *buf, size_t count, loff_t *ppos) { ssize_t ret; size_t copied; char *tmp_buf; if (count > APB1_LOG_SIZE) count = APB1_LOG_SIZE; tmp_buf = kmalloc(count, GFP_KERNEL); if (!tmp_buf) return -ENOMEM; copied = kfifo_out(&apb1_log_fifo, tmp_buf, count); ret = simple_read_from_buffer(buf, count, ppos, tmp_buf, copied); kfree(tmp_buf); return ret; } static const struct file_operations apb1_log_fops = { .read = apb1_log_read, }; static void usb_log_enable(struct es1_ap_dev *es1) { if (!IS_ERR_OR_NULL(apb1_log_task)) return; /* get log from APB1 */ apb1_log_task = kthread_run(apb1_log_poll, es1, "apb1_log"); if (IS_ERR(apb1_log_task)) return; apb1_log_dentry = debugfs_create_file("apb1_log", S_IRUGO, gb_debugfs_get(), NULL, &apb1_log_fops); } static void usb_log_disable(struct es1_ap_dev *es1) { if (IS_ERR_OR_NULL(apb1_log_task)) return; debugfs_remove(apb1_log_dentry); apb1_log_dentry = NULL; kthread_stop(apb1_log_task); apb1_log_task = NULL; } static ssize_t apb1_log_enable_read(struct file *f, char __user *buf, size_t count, loff_t *ppos) { char tmp_buf[3]; int enable = !IS_ERR_OR_NULL(apb1_log_task); sprintf(tmp_buf, "%d\n", enable); return simple_read_from_buffer(buf, count, ppos, tmp_buf, 3); } static ssize_t apb1_log_enable_write(struct file *f, const char __user *buf, size_t count, loff_t *ppos) { int enable; ssize_t retval; struct es1_ap_dev *es1 = (struct es1_ap_dev *)f->f_inode->i_private; retval = kstrtoint_from_user(buf, count, 10, &enable); if (retval) return retval; if (enable) usb_log_enable(es1); else usb_log_disable(es1); return count; } static const struct file_operations apb1_log_enable_fops = { .read = apb1_log_enable_read, .write = apb1_log_enable_write, }; /* * The ES1 USB Bridge device contains 4 endpoints * 1 Control - usual USB stuff + AP -> SVC messages * 1 Interrupt IN - SVC -> AP messages * 1 Bulk IN - CPort data in * 1 Bulk OUT - CPort data out */ static int ap_probe(struct usb_interface *interface, const struct usb_device_id *id) { struct es1_ap_dev *es1; struct greybus_host_device *hd; struct usb_device *udev; struct usb_host_interface *iface_desc; struct usb_endpoint_descriptor *endpoint; bool int_in_found = false; bool bulk_in_found = false; bool bulk_out_found = false; int retval = -ENOMEM; int i; u16 endo_id = 0x4755; // FIXME - get endo "ID" from the SVC u8 ap_intf_id = 0x01; // FIXME - get endo "ID" from the SVC u8 svc_interval = 0; udev = usb_get_dev(interface_to_usbdev(interface)); hd = greybus_create_hd(&es1_driver, &udev->dev, ES1_GBUF_MSG_SIZE_MAX); if (IS_ERR(hd)) { usb_put_dev(udev); return PTR_ERR(hd); } es1 = hd_to_es1(hd); es1->hd = hd; es1->usb_intf = interface; es1->usb_dev = udev; spin_lock_init(&es1->cport_out_urb_lock); usb_set_intfdata(interface, es1); /* Control endpoint is the pipe to talk to this AP, so save it off */ endpoint = &udev->ep0.desc; es1->control_endpoint = endpoint->bEndpointAddress; /* find all 3 of our endpoints */ iface_desc = interface->cur_altsetting; for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { endpoint = &iface_desc->endpoint[i].desc; if (usb_endpoint_is_int_in(endpoint)) { es1->svc_endpoint = endpoint->bEndpointAddress; svc_interval = endpoint->bInterval; int_in_found = true; } else if (usb_endpoint_is_bulk_in(endpoint)) { es1->cport_in_endpoint = endpoint->bEndpointAddress; bulk_in_found = true; } else if (usb_endpoint_is_bulk_out(endpoint)) { es1->cport_out_endpoint = endpoint->bEndpointAddress; bulk_out_found = true; } else { dev_err(&udev->dev, "Unknown endpoint type found, address %x\n", endpoint->bEndpointAddress); } } if ((int_in_found == false) || (bulk_in_found == false) || (bulk_out_found == false)) { dev_err(&udev->dev, "Not enough endpoints found in device, aborting!\n"); goto error; } /* Create our buffer and URB to get SVC messages, and start it up */ es1->svc_buffer = kmalloc(ES1_SVC_MSG_SIZE, GFP_KERNEL); if (!es1->svc_buffer) goto error; es1->svc_urb = usb_alloc_urb(0, GFP_KERNEL); if (!es1->svc_urb) goto error; usb_fill_int_urb(es1->svc_urb, udev, usb_rcvintpipe(udev, es1->svc_endpoint), es1->svc_buffer, ES1_SVC_MSG_SIZE, svc_in_callback, hd, svc_interval); /* Allocate buffers for our cport in messages and start them up */ for (i = 0; i < NUM_CPORT_IN_URB; ++i) { struct urb *urb; u8 *buffer; urb = usb_alloc_urb(0, GFP_KERNEL); if (!urb) goto error; buffer = kmalloc(ES1_GBUF_MSG_SIZE_MAX, GFP_KERNEL); if (!buffer) goto error; usb_fill_bulk_urb(urb, udev, usb_rcvbulkpipe(udev, es1->cport_in_endpoint), buffer, ES1_GBUF_MSG_SIZE_MAX, cport_in_callback, hd); es1->cport_in_urb[i] = urb; es1->cport_in_buffer[i] = buffer; retval = usb_submit_urb(urb, GFP_KERNEL); if (retval) goto error; } /* Allocate urbs for our CPort OUT messages */ for (i = 0; i < NUM_CPORT_OUT_URB; ++i) { struct urb *urb; urb = usb_alloc_urb(0, GFP_KERNEL); if (!urb) goto error; es1->cport_out_urb[i] = urb; es1->cport_out_urb_busy[i] = false; /* just to be anal */ } /* Start up our svc urb, which allows events to start flowing */ retval = usb_submit_urb(es1->svc_urb, GFP_KERNEL); if (retval) goto error; apb1_log_enable_dentry = debugfs_create_file("apb1_log_enable", (S_IWUSR | S_IRUGO), gb_debugfs_get(), es1, &apb1_log_enable_fops); /* * XXX Soon this will be initiated later, with a combination * XXX of a Control protocol probe operation and a * XXX subsequent Control protocol connected operation for * XXX the SVC connection. At that point we know we're * XXX properly connected to an Endo. */ retval = greybus_endo_setup(hd, endo_id, ap_intf_id); if (retval) goto error; return 0; error: ap_disconnect(interface); return retval; } static struct usb_driver es1_ap_driver = { .name = "es2_ap_driver", .probe = ap_probe, .disconnect = ap_disconnect, .id_table = id_table, }; module_usb_driver(es1_ap_driver); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Greg Kroah-Hartman ");