diff options
Diffstat (limited to 'drivers/net/wimax/i2400m/usb-notif.c')
| -rw-r--r-- | drivers/net/wimax/i2400m/usb-notif.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/drivers/net/wimax/i2400m/usb-notif.c b/drivers/net/wimax/i2400m/usb-notif.c new file mode 100644 index 000000000..fc1355d98 --- /dev/null +++ b/drivers/net/wimax/i2400m/usb-notif.c @@ -0,0 +1,259 @@ +/* + * Intel Wireless WiMAX Connection 2400m over USB + * Notification handling + * + * + * Copyright (C) 2007-2008 Intel Corporation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * + * Intel Corporation <linux-wimax@intel.com> + * Yanir Lubetkin <yanirx.lubetkin@intel.com> + * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> + * - Initial implementation + * + * + * The notification endpoint is active when the device is not in boot + * mode; in here we just read and get notifications; based on those, + * we act to either reinitialize the device after a reboot or to + * submit a RX request. + * + * ROADMAP + * + * i2400mu_usb_notification_setup() + * + * i2400mu_usb_notification_release() + * + * i2400mu_usb_notification_cb() Called when a URB is ready + * i2400mu_notif_grok() + * i2400m_is_boot_barker() + * i2400m_dev_reset_handle() + * i2400mu_rx_kick() + */ +#include <linux/usb.h> +#include <linux/slab.h> +#include "i2400m-usb.h" + + +#define D_SUBMODULE notif +#include "usb-debug-levels.h" + + +static const +__le32 i2400m_ZERO_BARKER[4] = { 0, 0, 0, 0 }; + + +/* + * Process a received notification + * + * In normal operation mode, we can only receive two types of payloads + * on the notification endpoint: + * + * - a reboot barker, we do a bootstrap (the device has reseted). + * + * - a block of zeroes: there is pending data in the IN endpoint + */ +static +int i2400mu_notification_grok(struct i2400mu *i2400mu, const void *buf, + size_t buf_len) +{ + int ret; + struct device *dev = &i2400mu->usb_iface->dev; + struct i2400m *i2400m = &i2400mu->i2400m; + + d_fnstart(4, dev, "(i2400m %p buf %p buf_len %zu)\n", + i2400mu, buf, buf_len); + ret = -EIO; + if (buf_len < sizeof(i2400m_ZERO_BARKER)) + /* Not a bug, just ignore */ + goto error_bad_size; + ret = 0; + if (!memcmp(i2400m_ZERO_BARKER, buf, sizeof(i2400m_ZERO_BARKER))) { + i2400mu_rx_kick(i2400mu); + goto out; + } + ret = i2400m_is_boot_barker(i2400m, buf, buf_len); + if (unlikely(ret >= 0)) + ret = i2400m_dev_reset_handle(i2400m, "device rebooted"); + else /* Unknown or unexpected data in the notif message */ + i2400m_unknown_barker(i2400m, buf, buf_len); +error_bad_size: +out: + d_fnend(4, dev, "(i2400m %p buf %p buf_len %zu) = %d\n", + i2400mu, buf, buf_len, ret); + return ret; +} + + +/* + * URB callback for the notification endpoint + * + * @urb: the urb received from the notification endpoint + * + * This function will just process the USB side of the transaction, + * checking everything is fine, pass the processing to + * i2400m_notification_grok() and resubmit the URB. + */ +static +void i2400mu_notification_cb(struct urb *urb) +{ + int ret; + struct i2400mu *i2400mu = urb->context; + struct device *dev = &i2400mu->usb_iface->dev; + + d_fnstart(4, dev, "(urb %p status %d actual_length %d)\n", + urb, urb->status, urb->actual_length); + ret = urb->status; + switch (ret) { + case 0: + ret = i2400mu_notification_grok(i2400mu, urb->transfer_buffer, + urb->actual_length); + if (ret == -EIO && edc_inc(&i2400mu->urb_edc, EDC_MAX_ERRORS, + EDC_ERROR_TIMEFRAME)) + goto error_exceeded; + if (ret == -ENOMEM) /* uff...power cycle? shutdown? */ + goto error_exceeded; + break; + case -EINVAL: /* while removing driver */ + case -ENODEV: /* dev disconnect ... */ + case -ENOENT: /* ditto */ + case -ESHUTDOWN: /* URB killed */ + case -ECONNRESET: /* disconnection */ + goto out; /* Notify around */ + default: /* Some error? */ + if (edc_inc(&i2400mu->urb_edc, + EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) + goto error_exceeded; + dev_err(dev, "notification: URB error %d, retrying\n", + urb->status); + } + usb_mark_last_busy(i2400mu->usb_dev); + ret = usb_submit_urb(i2400mu->notif_urb, GFP_ATOMIC); + switch (ret) { + case 0: + case -EINVAL: /* while removing driver */ + case -ENODEV: /* dev disconnect ... */ + case -ENOENT: /* ditto */ + case -ESHUTDOWN: /* URB killed */ + case -ECONNRESET: /* disconnection */ + break; /* just ignore */ + default: /* Some error? */ + dev_err(dev, "notification: cannot submit URB: %d\n", ret); + goto error_submit; + } + d_fnend(4, dev, "(urb %p status %d actual_length %d) = void\n", + urb, urb->status, urb->actual_length); + return; + +error_exceeded: + dev_err(dev, "maximum errors in notification URB exceeded; " + "resetting device\n"); +error_submit: + usb_queue_reset_device(i2400mu->usb_iface); +out: + d_fnend(4, dev, "(urb %p status %d actual_length %d) = void\n", + urb, urb->status, urb->actual_length); +} + + +/* + * setup the notification endpoint + * + * @i2400m: device descriptor + * + * This procedure prepares the notification urb and handler for receiving + * unsolicited barkers from the device. + */ +int i2400mu_notification_setup(struct i2400mu *i2400mu) +{ + struct device *dev = &i2400mu->usb_iface->dev; + int usb_pipe, ret = 0; + struct usb_endpoint_descriptor *epd; + char *buf; + + d_fnstart(4, dev, "(i2400m %p)\n", i2400mu); + buf = kmalloc(I2400MU_MAX_NOTIFICATION_LEN, GFP_KERNEL | GFP_DMA); + if (buf == NULL) { + ret = -ENOMEM; + goto error_buf_alloc; + } + + i2400mu->notif_urb = usb_alloc_urb(0, GFP_KERNEL); + if (!i2400mu->notif_urb) { + ret = -ENOMEM; + dev_err(dev, "notification: cannot allocate URB\n"); + goto error_alloc_urb; + } + epd = usb_get_epd(i2400mu->usb_iface, + i2400mu->endpoint_cfg.notification); + usb_pipe = usb_rcvintpipe(i2400mu->usb_dev, epd->bEndpointAddress); + usb_fill_int_urb(i2400mu->notif_urb, i2400mu->usb_dev, usb_pipe, + buf, I2400MU_MAX_NOTIFICATION_LEN, + i2400mu_notification_cb, i2400mu, epd->bInterval); + ret = usb_submit_urb(i2400mu->notif_urb, GFP_KERNEL); + if (ret != 0) { + dev_err(dev, "notification: cannot submit URB: %d\n", ret); + goto error_submit; + } + d_fnend(4, dev, "(i2400m %p) = %d\n", i2400mu, ret); + return ret; + +error_submit: + usb_free_urb(i2400mu->notif_urb); +error_alloc_urb: + kfree(buf); +error_buf_alloc: + d_fnend(4, dev, "(i2400m %p) = %d\n", i2400mu, ret); + return ret; +} + + +/* + * Tear down of the notification mechanism + * + * @i2400m: device descriptor + * + * Kill the interrupt endpoint urb, free any allocated resources. + * + * We need to check if we have done it before as for example, + * _suspend() call this; if after a suspend() we get a _disconnect() + * (as the case is when hibernating), nothing bad happens. + */ +void i2400mu_notification_release(struct i2400mu *i2400mu) +{ + struct device *dev = &i2400mu->usb_iface->dev; + + d_fnstart(4, dev, "(i2400mu %p)\n", i2400mu); + if (i2400mu->notif_urb != NULL) { + usb_kill_urb(i2400mu->notif_urb); + kfree(i2400mu->notif_urb->transfer_buffer); + usb_free_urb(i2400mu->notif_urb); + i2400mu->notif_urb = NULL; + } + d_fnend(4, dev, "(i2400mu %p)\n", i2400mu); +} |