diff options
Diffstat (limited to 'drivers/net/wimax/i2400m/i2400m-usb.h')
| -rw-r--r-- | drivers/net/wimax/i2400m/i2400m-usb.h | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/drivers/net/wimax/i2400m/i2400m-usb.h b/drivers/net/wimax/i2400m/i2400m-usb.h new file mode 100644 index 000000000000..6f76558b170f --- /dev/null +++ b/drivers/net/wimax/i2400m/i2400m-usb.h @@ -0,0 +1,264 @@ +/* + * Intel Wireless WiMAX Connection 2400m + * USB-specific i2400m driver definitions + * + * + * 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> + * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> + * Yanir Lubetkin <yanirx.lubetkin@intel.com> + * - Initial implementation + * + * + * This driver implements the bus-specific part of the i2400m for + * USB. Check i2400m.h for a generic driver description. + * + * ARCHITECTURE + * + * This driver listens to notifications sent from the notification + * endpoint (in usb-notif.c); when data is ready to read, the code in + * there schedules a read from the device (usb-rx.c) and then passes + * the data to the generic RX code (rx.c). + * + * When the generic driver needs to send data (network or control), it + * queues up in the TX FIFO (tx.c) and that will notify the driver + * through the i2400m->bus_tx_kick() callback + * (usb-tx.c:i2400mu_bus_tx_kick) which will send the items in the + * FIFO queue. + * + * This driver, as well, implements the USB-specific ops for the generic + * driver to be able to setup/teardown communication with the device + * [i2400m_bus_dev_start() and i2400m_bus_dev_stop()], reseting the + * device [i2400m_bus_reset()] and performing firmware upload + * [i2400m_bus_bm_cmd() and i2400_bus_bm_wait_for_ack()]. + */ + +#ifndef __I2400M_USB_H__ +#define __I2400M_USB_H__ + +#include "i2400m.h" +#include <linux/kthread.h> + + +/* + * Error Density Count: cheapo error density (over time) counter + * + * Originally by Reinette Chatre <reinette.chatre@intel.com> + * + * Embed an 'struct edc' somewhere. Each time there is a soft or + * retryable error, call edc_inc() and check if the error top + * watermark has been reached. + */ +enum { + EDC_MAX_ERRORS = 10, + EDC_ERROR_TIMEFRAME = HZ, +}; + +/* error density counter */ +struct edc { + unsigned long timestart; + u16 errorcount; +}; + +static inline void edc_init(struct edc *edc) +{ + edc->timestart = jiffies; +} + +/** + * edc_inc - report a soft error and check if we are over the watermark + * + * @edc: pointer to error density counter. + * @max_err: maximum number of errors we can accept over the timeframe + * @timeframe: lenght of the timeframe (in jiffies). + * + * Returns: !0 1 if maximum acceptable errors per timeframe has been + * exceeded. 0 otherwise. + * + * This is way to determine if the number of acceptable errors per time + * period has been exceeded. It is not accurate as there are cases in which + * this scheme will not work, for example if there are periodic occurences + * of errors that straddle updates to the start time. This scheme is + * sufficient for our usage. + * + * To use, embed a 'struct edc' somewhere, initialize it with + * edc_init() and when an error hits: + * + * if (do_something_fails_with_a_soft_error) { + * if (edc_inc(&my->edc, MAX_ERRORS, MAX_TIMEFRAME)) + * Ops, hard error, do something about it + * else + * Retry or ignore, depending on whatever + * } + */ +static inline int edc_inc(struct edc *edc, u16 max_err, u16 timeframe) +{ + unsigned long now; + + now = jiffies; + if (now - edc->timestart > timeframe) { + edc->errorcount = 1; + edc->timestart = now; + } else if (++edc->errorcount > max_err) { + edc->errorcount = 0; + edc->timestart = now; + return 1; + } + return 0; +} + +/* Host-Device interface for USB */ +enum { + I2400MU_MAX_NOTIFICATION_LEN = 256, + I2400MU_BLK_SIZE = 16, + I2400MU_PL_SIZE_MAX = 0x3EFF, + + /* Endpoints */ + I2400MU_EP_BULK_OUT = 0, + I2400MU_EP_NOTIFICATION, + I2400MU_EP_RESET_COLD, + I2400MU_EP_BULK_IN, +}; + + +/** + * struct i2400mu - descriptor for a USB connected i2400m + * + * @i2400m: bus-generic i2400m implementation; has to be first (see + * it's documentation in i2400m.h). + * + * @usb_dev: pointer to our USB device + * + * @usb_iface: pointer to our USB interface + * + * @urb_edc: error density counter; used to keep a density-on-time tab + * on how many soft (retryable or ignorable) errors we get. If we + * go over the threshold, we consider the bus transport is failing + * too much and reset. + * + * @notif_urb: URB for receiving notifications from the device. + * + * @tx_kthread: thread we use for data TX. We use a thread because in + * order to do deep power saving and put the device to sleep, we + * need to call usb_autopm_*() [blocking functions]. + * + * @tx_wq: waitqueue for the TX kthread to sleep when there is no data + * to be sent; when more data is available, it is woken up by + * i2400mu_bus_tx_kick(). + * + * @rx_kthread: thread we use for data RX. We use a thread because in + * order to do deep power saving and put the device to sleep, we + * need to call usb_autopm_*() [blocking functions]. + * + * @rx_wq: waitqueue for the RX kthread to sleep when there is no data + * to receive. When data is available, it is woken up by + * usb-notif.c:i2400mu_notification_grok(). + * + * @rx_pending_count: number of rx-data-ready notifications that were + * still not handled by the RX kthread. + * + * @rx_size: current RX buffer size that is being used. + * + * @rx_size_acc: accumulator of the sizes of the previous read + * transactions. + * + * @rx_size_cnt: number of read transactions accumulated in + * @rx_size_acc. + * + * @do_autopm: disable(0)/enable(>0) calling the + * usb_autopm_get/put_interface() barriers when executing + * commands. See doc in i2400mu_suspend() for more information. + * + * @rx_size_auto_shrink: if true, the rx_size is shrinked + * automatically based on the average size of the received + * transactions. This allows the receive code to allocate smaller + * chunks of memory and thus reduce pressure on the memory + * allocator by not wasting so much space. By default it is + * enabled. + * + * @debugfs_dentry: hookup for debugfs files. + * These have to be in a separate directory, a child of + * (wimax_dev->debugfs_dentry) so they can be removed when the + * module unloads, as we don't keep each dentry. + */ +struct i2400mu { + struct i2400m i2400m; /* FIRST! See doc */ + + struct usb_device *usb_dev; + struct usb_interface *usb_iface; + struct edc urb_edc; /* Error density counter */ + + struct urb *notif_urb; + struct task_struct *tx_kthread; + wait_queue_head_t tx_wq; + + struct task_struct *rx_kthread; + wait_queue_head_t rx_wq; + atomic_t rx_pending_count; + size_t rx_size, rx_size_acc, rx_size_cnt; + atomic_t do_autopm; + u8 rx_size_auto_shrink; + + struct dentry *debugfs_dentry; +}; + + +static inline +void i2400mu_init(struct i2400mu *i2400mu) +{ + i2400m_init(&i2400mu->i2400m); + edc_init(&i2400mu->urb_edc); + init_waitqueue_head(&i2400mu->tx_wq); + atomic_set(&i2400mu->rx_pending_count, 0); + init_waitqueue_head(&i2400mu->rx_wq); + i2400mu->rx_size = PAGE_SIZE - sizeof(struct skb_shared_info); + atomic_set(&i2400mu->do_autopm, 1); + i2400mu->rx_size_auto_shrink = 1; +} + +extern int i2400mu_notification_setup(struct i2400mu *); +extern void i2400mu_notification_release(struct i2400mu *); + +extern int i2400mu_rx_setup(struct i2400mu *); +extern void i2400mu_rx_release(struct i2400mu *); +extern void i2400mu_rx_kick(struct i2400mu *); + +extern int i2400mu_tx_setup(struct i2400mu *); +extern void i2400mu_tx_release(struct i2400mu *); +extern void i2400mu_bus_tx_kick(struct i2400m *); + +extern ssize_t i2400mu_bus_bm_cmd_send(struct i2400m *, + const struct i2400m_bootrom_header *, + size_t, int); +extern ssize_t i2400mu_bus_bm_wait_for_ack(struct i2400m *, + struct i2400m_bootrom_header *, + size_t); +#endif /* #ifndef __I2400M_USB_H__ */ |