/*
* 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;
};
struct i2400m_endpoint_cfg {
unsigned char bulk_out;
unsigned char notification;
unsigned char reset_cold;
unsigned char bulk_in;
};
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: length 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 occurrences
* 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 {
I2400M_USB_BOOT_RETRIES = 3,
I2400MU_MAX_NOTIFICATION_LEN = 256,
I2400MU_BLK_SIZE = 16,
I2400MU_PL_SIZE_MAX = 0x3EFF,
/* Device IDs */
USB_DEVICE_ID_I6050 = 0x0186,
USB_DEVICE_ID_I6050_2 = 0x0188,
USB_DEVICE_ID_I6250 = 0x0187,
};
/**
* 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 shrunk
* 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 i2400m_endpoint_cfg endpoint_cfg;
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;
unsigned i6050:1; /* 1 if this is a 6050 based SKU */
};
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__ */
