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-rw-r--r--drivers/net/wimax/i2400m/usb-notif.c269
-rw-r--r--drivers/net/wimax/i2400m/usb-rx.c417
-rw-r--r--drivers/net/wimax/i2400m/usb-tx.c229
3 files changed, 915 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 000000000000..9702c22b2497
--- /dev/null
+++ b/drivers/net/wimax/i2400m/usb-notif.c
@@ -0,0 +1,269 @@
1/*
2 * Intel Wireless WiMAX Connection 2400m over USB
3 * Notification handling
4 *
5 *
6 * Copyright (C) 2007-2008 Intel Corporation. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * * Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * * Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 * * Neither the name of Intel Corporation nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
28 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
32 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 *
34 *
35 * Intel Corporation <linux-wimax@intel.com>
36 * Yanir Lubetkin <yanirx.lubetkin@intel.com>
37 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
38 * - Initial implementation
39 *
40 *
41 * The notification endpoint is active when the device is not in boot
42 * mode; in here we just read and get notifications; based on those,
43 * we act to either reinitialize the device after a reboot or to
44 * submit a RX request.
45 *
46 * ROADMAP
47 *
48 * i2400mu_usb_notification_setup()
49 *
50 * i2400mu_usb_notification_release()
51 *
52 * i2400mu_usb_notification_cb() Called when a URB is ready
53 * i2400mu_notif_grok()
54 * i2400m_dev_reset_handle()
55 * i2400mu_rx_kick()
56 */
57#include <linux/usb.h>
58#include "i2400m-usb.h"
59
60
61#define D_SUBMODULE notif
62#include "usb-debug-levels.h"
63
64
65static const
66__le32 i2400m_ZERO_BARKER[4] = { 0, 0, 0, 0 };
67
68
69/*
70 * Process a received notification
71 *
72 * In normal operation mode, we can only receive two types of payloads
73 * on the notification endpoint:
74 *
75 * - a reboot barker, we do a bootstrap (the device has reseted).
76 *
77 * - a block of zeroes: there is pending data in the IN endpoint
78 */
79static
80int i2400mu_notification_grok(struct i2400mu *i2400mu, const void *buf,
81 size_t buf_len)
82{
83 int ret;
84 struct device *dev = &i2400mu->usb_iface->dev;
85 struct i2400m *i2400m = &i2400mu->i2400m;
86
87 d_fnstart(4, dev, "(i2400m %p buf %p buf_len %zu)\n",
88 i2400mu, buf, buf_len);
89 ret = -EIO;
90 if (buf_len < sizeof(i2400m_NBOOT_BARKER))
91 /* Not a bug, just ignore */
92 goto error_bad_size;
93 if (!memcmp(i2400m_NBOOT_BARKER, buf, sizeof(i2400m_NBOOT_BARKER))
94 || !memcmp(i2400m_SBOOT_BARKER, buf, sizeof(i2400m_SBOOT_BARKER)))
95 ret = i2400m_dev_reset_handle(i2400m);
96 else if (!memcmp(i2400m_ZERO_BARKER, buf, sizeof(i2400m_ZERO_BARKER))) {
97 i2400mu_rx_kick(i2400mu);
98 ret = 0;
99 } else { /* Unknown or unexpected data in the notif message */
100 char prefix[64];
101 ret = -EIO;
102 dev_err(dev, "HW BUG? Unknown/unexpected data in notification "
103 "message (%zu bytes)\n", buf_len);
104 snprintf(prefix, sizeof(prefix), "%s %s: ",
105 dev_driver_string(dev) , dev->bus_id);
106 if (buf_len > 64) {
107 print_hex_dump(KERN_ERR, prefix, DUMP_PREFIX_OFFSET,
108 8, 4, buf, 64, 0);
109 printk(KERN_ERR "%s... (only first 64 bytes "
110 "dumped)\n", prefix);
111 } else
112 print_hex_dump(KERN_ERR, prefix, DUMP_PREFIX_OFFSET,
113 8, 4, buf, buf_len, 0);
114 }
115error_bad_size:
116 d_fnend(4, dev, "(i2400m %p buf %p buf_len %zu) = %d\n",
117 i2400mu, buf, buf_len, ret);
118 return ret;
119}
120
121
122/*
123 * URB callback for the notification endpoint
124 *
125 * @urb: the urb received from the notification endpoint
126 *
127 * This function will just process the USB side of the transaction,
128 * checking everything is fine, pass the processing to
129 * i2400m_notification_grok() and resubmit the URB.
130 */
131static
132void i2400mu_notification_cb(struct urb *urb)
133{
134 int ret;
135 struct i2400mu *i2400mu = urb->context;
136 struct device *dev = &i2400mu->usb_iface->dev;
137
138 d_fnstart(4, dev, "(urb %p status %d actual_length %d)\n",
139 urb, urb->status, urb->actual_length);
140 ret = urb->status;
141 switch (ret) {
142 case 0:
143 ret = i2400mu_notification_grok(i2400mu, urb->transfer_buffer,
144 urb->actual_length);
145 if (ret == -EIO && edc_inc(&i2400mu->urb_edc, EDC_MAX_ERRORS,
146 EDC_ERROR_TIMEFRAME))
147 goto error_exceeded;
148 if (ret == -ENOMEM) /* uff...power cycle? shutdown? */
149 goto error_exceeded;
150 break;
151 case -EINVAL: /* while removing driver */
152 case -ENODEV: /* dev disconnect ... */
153 case -ENOENT: /* ditto */
154 case -ESHUTDOWN: /* URB killed */
155 case -ECONNRESET: /* disconnection */
156 goto out; /* Notify around */
157 default: /* Some error? */
158 if (edc_inc(&i2400mu->urb_edc,
159 EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME))
160 goto error_exceeded;
161 dev_err(dev, "notification: URB error %d, retrying\n",
162 urb->status);
163 }
164 usb_mark_last_busy(i2400mu->usb_dev);
165 ret = usb_submit_urb(i2400mu->notif_urb, GFP_ATOMIC);
166 switch (ret) {
167 case 0:
168 case -EINVAL: /* while removing driver */
169 case -ENODEV: /* dev disconnect ... */
170 case -ENOENT: /* ditto */
171 case -ESHUTDOWN: /* URB killed */
172 case -ECONNRESET: /* disconnection */
173 break; /* just ignore */
174 default: /* Some error? */
175 dev_err(dev, "notification: cannot submit URB: %d\n", ret);
176 goto error_submit;
177 }
178 d_fnend(4, dev, "(urb %p status %d actual_length %d) = void\n",
179 urb, urb->status, urb->actual_length);
180 return;
181
182error_exceeded:
183 dev_err(dev, "maximum errors in notification URB exceeded; "
184 "resetting device\n");
185error_submit:
186 usb_queue_reset_device(i2400mu->usb_iface);
187out:
188 d_fnend(4, dev, "(urb %p status %d actual_length %d) = void\n",
189 urb, urb->status, urb->actual_length);
190 return;
191}
192
193
194/*
195 * setup the notification endpoint
196 *
197 * @i2400m: device descriptor
198 *
199 * This procedure prepares the notification urb and handler for receiving
200 * unsolicited barkers from the device.
201 */
202int i2400mu_notification_setup(struct i2400mu *i2400mu)
203{
204 struct device *dev = &i2400mu->usb_iface->dev;
205 int usb_pipe, ret = 0;
206 struct usb_endpoint_descriptor *epd;
207 char *buf;
208
209 d_fnstart(4, dev, "(i2400m %p)\n", i2400mu);
210 buf = kmalloc(I2400MU_MAX_NOTIFICATION_LEN, GFP_KERNEL | GFP_DMA);
211 if (buf == NULL) {
212 dev_err(dev, "notification: buffer allocation failed\n");
213 ret = -ENOMEM;
214 goto error_buf_alloc;
215 }
216
217 i2400mu->notif_urb = usb_alloc_urb(0, GFP_KERNEL);
218 if (!i2400mu->notif_urb) {
219 ret = -ENOMEM;
220 dev_err(dev, "notification: cannot allocate URB\n");
221 goto error_alloc_urb;
222 }
223 epd = usb_get_epd(i2400mu->usb_iface, I2400MU_EP_NOTIFICATION);
224 usb_pipe = usb_rcvintpipe(i2400mu->usb_dev, epd->bEndpointAddress);
225 usb_fill_int_urb(i2400mu->notif_urb, i2400mu->usb_dev, usb_pipe,
226 buf, I2400MU_MAX_NOTIFICATION_LEN,
227 i2400mu_notification_cb, i2400mu, epd->bInterval);
228 ret = usb_submit_urb(i2400mu->notif_urb, GFP_KERNEL);
229 if (ret != 0) {
230 dev_err(dev, "notification: cannot submit URB: %d\n", ret);
231 goto error_submit;
232 }
233 d_fnend(4, dev, "(i2400m %p) = %d\n", i2400mu, ret);
234 return ret;
235
236error_submit:
237 usb_free_urb(i2400mu->notif_urb);
238error_alloc_urb:
239 kfree(buf);
240error_buf_alloc:
241 d_fnend(4, dev, "(i2400m %p) = %d\n", i2400mu, ret);
242 return ret;
243}
244
245
246/*
247 * Tear down of the notification mechanism
248 *
249 * @i2400m: device descriptor
250 *
251 * Kill the interrupt endpoint urb, free any allocated resources.
252 *
253 * We need to check if we have done it before as for example,
254 * _suspend() call this; if after a suspend() we get a _disconnect()
255 * (as the case is when hibernating), nothing bad happens.
256 */
257void i2400mu_notification_release(struct i2400mu *i2400mu)
258{
259 struct device *dev = &i2400mu->usb_iface->dev;
260
261 d_fnstart(4, dev, "(i2400mu %p)\n", i2400mu);
262 if (i2400mu->notif_urb != NULL) {
263 usb_kill_urb(i2400mu->notif_urb);
264 kfree(i2400mu->notif_urb->transfer_buffer);
265 usb_free_urb(i2400mu->notif_urb);
266 i2400mu->notif_urb = NULL;
267 }
268 d_fnend(4, dev, "(i2400mu %p)\n", i2400mu);
269}
diff --git a/drivers/net/wimax/i2400m/usb-rx.c b/drivers/net/wimax/i2400m/usb-rx.c
new file mode 100644
index 000000000000..074cc1f89853
--- /dev/null
+++ b/drivers/net/wimax/i2400m/usb-rx.c
@@ -0,0 +1,417 @@
1/*
2 * Intel Wireless WiMAX Connection 2400m
3 * USB RX handling
4 *
5 *
6 * Copyright (C) 2007-2008 Intel Corporation. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * * Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * * Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 * * Neither the name of Intel Corporation nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
28 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
32 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 *
34 *
35 * Intel Corporation <linux-wimax@intel.com>
36 * Yanir Lubetkin <yanirx.lubetkin@intel.com>
37 * - Initial implementation
38 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
39 * - Use skb_clone(), break up processing in chunks
40 * - Split transport/device specific
41 * - Make buffer size dynamic to exert less memory pressure
42 *
43 *
44 * This handles the RX path on USB.
45 *
46 * When a notification is received that says 'there is RX data ready',
47 * we call i2400mu_rx_kick(); that wakes up the RX kthread, which
48 * reads a buffer from USB and passes it to i2400m_rx() in the generic
49 * handling code. The RX buffer has an specific format that is
50 * described in rx.c.
51 *
52 * We use a kernel thread in a loop because:
53 *
54 * - we want to be able to call the USB power management get/put
55 * functions (blocking) before each transaction.
56 *
57 * - We might get a lot of notifications and we don't want to submit
58 * a zillion reads; by serializing, we are throttling.
59 *
60 * - RX data processing can get heavy enough so that it is not
61 * appropiate for doing it in the USB callback; thus we run it in a
62 * process context.
63 *
64 * We provide a read buffer of an arbitrary size (short of a page); if
65 * the callback reports -EOVERFLOW, it means it was too small, so we
66 * just double the size and retry (being careful to append, as
67 * sometimes the device provided some data). Every now and then we
68 * check if the average packet size is smaller than the current packet
69 * size and if so, we halve it. At the end, the size of the
70 * preallocated buffer should be following the average received
71 * transaction size, adapting dynamically to it.
72 *
73 * ROADMAP
74 *
75 * i2400mu_rx_kick() Called from notif.c when we get a
76 * 'data ready' notification
77 * i2400mu_rxd() Kernel RX daemon
78 * i2400mu_rx() Receive USB data
79 * i2400m_rx() Send data to generic i2400m RX handling
80 *
81 * i2400mu_rx_setup() called from i2400mu_bus_dev_start()
82 *
83 * i2400mu_rx_release() called from i2400mu_bus_dev_stop()
84 */
85#include <linux/workqueue.h>
86#include <linux/usb.h>
87#include "i2400m-usb.h"
88
89
90#define D_SUBMODULE rx
91#include "usb-debug-levels.h"
92
93/*
94 * Dynamic RX size
95 *
96 * We can't let the rx_size be a multiple of 512 bytes (the RX
97 * endpoint's max packet size). On some USB host controllers (we
98 * haven't been able to fully characterize which), if the device is
99 * about to send (for example) X bytes and we only post a buffer to
100 * receive n*512, it will fail to mark that as babble (so that
101 * i2400mu_rx() [case -EOVERFLOW] can resize the buffer and get the
102 * rest).
103 *
104 * So on growing or shrinking, if it is a multiple of the
105 * maxpacketsize, we remove some (instead of incresing some, so in a
106 * buddy allocator we try to waste less space).
107 *
108 * Note we also need a hook for this on i2400mu_rx() -- when we do the
109 * first read, we are sure we won't hit this spot because
110 * i240mm->rx_size has been set properly. However, if we have to
111 * double because of -EOVERFLOW, when we launch the read to get the
112 * rest of the data, we *have* to make sure that also is not a
113 * multiple of the max_pkt_size.
114 */
115
116static
117size_t i2400mu_rx_size_grow(struct i2400mu *i2400mu)
118{
119 struct device *dev = &i2400mu->usb_iface->dev;
120 size_t rx_size;
121 const size_t max_pkt_size = 512;
122
123 rx_size = 2 * i2400mu->rx_size;
124 if (rx_size % max_pkt_size == 0) {
125 rx_size -= 8;
126 d_printf(1, dev,
127 "RX: expected size grew to %zu [adjusted -8] "
128 "from %zu\n",
129 rx_size, i2400mu->rx_size);
130 } else
131 d_printf(1, dev,
132 "RX: expected size grew to %zu from %zu\n",
133 rx_size, i2400mu->rx_size);
134 return rx_size;
135}
136
137
138static
139void i2400mu_rx_size_maybe_shrink(struct i2400mu *i2400mu)
140{
141 const size_t max_pkt_size = 512;
142 struct device *dev = &i2400mu->usb_iface->dev;
143
144 if (unlikely(i2400mu->rx_size_cnt >= 100
145 && i2400mu->rx_size_auto_shrink)) {
146 size_t avg_rx_size =
147 i2400mu->rx_size_acc / i2400mu->rx_size_cnt;
148 size_t new_rx_size = i2400mu->rx_size / 2;
149 if (avg_rx_size < new_rx_size) {
150 if (new_rx_size % max_pkt_size == 0) {
151 new_rx_size -= 8;
152 d_printf(1, dev,
153 "RX: expected size shrank to %zu "
154 "[adjusted -8] from %zu\n",
155 new_rx_size, i2400mu->rx_size);
156 } else
157 d_printf(1, dev,
158 "RX: expected size shrank to %zu "
159 "from %zu\n",
160 new_rx_size, i2400mu->rx_size);
161 i2400mu->rx_size = new_rx_size;
162 i2400mu->rx_size_cnt = 0;
163 i2400mu->rx_size_acc = i2400mu->rx_size;
164 }
165 }
166}
167
168/*
169 * Receive a message with payloads from the USB bus into an skb
170 *
171 * @i2400mu: USB device descriptor
172 * @rx_skb: skb where to place the received message
173 *
174 * Deals with all the USB-specifics of receiving, dynamically
175 * increasing the buffer size if so needed. Returns the payload in the
176 * skb, ready to process. On a zero-length packet, we retry.
177 *
178 * On soft USB errors, we retry (until they become too frequent and
179 * then are promoted to hard); on hard USB errors, we reset the
180 * device. On other errors (skb realloacation, we just drop it and
181 * hope for the next invocation to solve it).
182 *
183 * Returns: pointer to the skb if ok, ERR_PTR on error.
184 * NOTE: this function might realloc the skb (if it is too small),
185 * so always update with the one returned.
186 * ERR_PTR() is < 0 on error.
187 */
188static
189struct sk_buff *i2400mu_rx(struct i2400mu *i2400mu, struct sk_buff *rx_skb)
190{
191 int result = 0;
192 struct device *dev = &i2400mu->usb_iface->dev;
193 int usb_pipe, read_size, rx_size, do_autopm;
194 struct usb_endpoint_descriptor *epd;
195 const size_t max_pkt_size = 512;
196
197 d_fnstart(4, dev, "(i2400mu %p)\n", i2400mu);
198 do_autopm = atomic_read(&i2400mu->do_autopm);
199 result = do_autopm ?
200 usb_autopm_get_interface(i2400mu->usb_iface) : 0;
201 if (result < 0) {
202 dev_err(dev, "RX: can't get autopm: %d\n", result);
203 do_autopm = 0;
204 }
205 epd = usb_get_epd(i2400mu->usb_iface, I2400MU_EP_BULK_IN);
206 usb_pipe = usb_rcvbulkpipe(i2400mu->usb_dev, epd->bEndpointAddress);
207retry:
208 rx_size = skb_end_pointer(rx_skb) - rx_skb->data - rx_skb->len;
209 if (unlikely(rx_size % max_pkt_size == 0)) {
210 rx_size -= 8;
211 d_printf(1, dev, "RX: rx_size adapted to %d [-8]\n", rx_size);
212 }
213 result = usb_bulk_msg(
214 i2400mu->usb_dev, usb_pipe, rx_skb->data + rx_skb->len,
215 rx_size, &read_size, HZ);
216 usb_mark_last_busy(i2400mu->usb_dev);
217 switch (result) {
218 case 0:
219 if (read_size == 0)
220 goto retry; /* ZLP, just resubmit */
221 skb_put(rx_skb, read_size);
222 break;
223 case -EINVAL: /* while removing driver */
224 case -ENODEV: /* dev disconnect ... */
225 case -ENOENT: /* just ignore it */
226 case -ESHUTDOWN:
227 case -ECONNRESET:
228 break;
229 case -EOVERFLOW: { /* too small, reallocate */
230 struct sk_buff *new_skb;
231 rx_size = i2400mu_rx_size_grow(i2400mu);
232 if (rx_size <= (1 << 16)) /* cap it */
233 i2400mu->rx_size = rx_size;
234 else if (printk_ratelimit()) {
235 dev_err(dev, "BUG? rx_size up to %d\n", rx_size);
236 result = -EINVAL;
237 goto out;
238 }
239 skb_put(rx_skb, read_size);
240 new_skb = skb_copy_expand(rx_skb, 0, rx_size - rx_skb->len,
241 GFP_KERNEL);
242 if (new_skb == NULL) {
243 if (printk_ratelimit())
244 dev_err(dev, "RX: Can't reallocate skb to %d; "
245 "RX dropped\n", rx_size);
246 kfree(rx_skb);
247 result = 0;
248 goto out; /* drop it...*/
249 }
250 kfree_skb(rx_skb);
251 rx_skb = new_skb;
252 i2400mu->rx_size_cnt = 0;
253 i2400mu->rx_size_acc = i2400mu->rx_size;
254 d_printf(1, dev, "RX: size changed to %d, received %d, "
255 "copied %d, capacity %ld\n",
256 rx_size, read_size, rx_skb->len,
257 (long) (skb_end_pointer(new_skb) - new_skb->head));
258 goto retry;
259 }
260 /* In most cases, it happens due to the hardware scheduling a
261 * read when there was no data - unfortunately, we have no way
262 * to tell this timeout from a USB timeout. So we just ignore
263 * it. */
264 case -ETIMEDOUT:
265 dev_err(dev, "RX: timeout: %d\n", result);
266 result = 0;
267 break;
268 default: /* Any error */
269 if (edc_inc(&i2400mu->urb_edc,
270 EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME))
271 goto error_reset;
272 dev_err(dev, "RX: error receiving URB: %d, retrying\n", result);
273 goto retry;
274 }
275out:
276 if (do_autopm)
277 usb_autopm_put_interface(i2400mu->usb_iface);
278 d_fnend(4, dev, "(i2400mu %p) = %p\n", i2400mu, rx_skb);
279 return rx_skb;
280
281error_reset:
282 dev_err(dev, "RX: maximum errors in URB exceeded; "
283 "resetting device\n");
284 usb_queue_reset_device(i2400mu->usb_iface);
285 rx_skb = ERR_PTR(result);
286 goto out;
287}
288
289
290/*
291 * Kernel thread for USB reception of data
292 *
293 * This thread waits for a kick; once kicked, it will allocate an skb
294 * and receive a single message to it from USB (using
295 * i2400mu_rx()). Once received, it is passed to the generic i2400m RX
296 * code for processing.
297 *
298 * When done processing, it runs some dirty statistics to verify if
299 * the last 100 messages received were smaller than half of the
300 * current RX buffer size. In that case, the RX buffer size is
301 * halved. This will helps lowering the pressure on the memory
302 * allocator.
303 *
304 * Hard errors force the thread to exit.
305 */
306static
307int i2400mu_rxd(void *_i2400mu)
308{
309 int result = 0;
310 struct i2400mu *i2400mu = _i2400mu;
311 struct i2400m *i2400m = &i2400mu->i2400m;
312 struct device *dev = &i2400mu->usb_iface->dev;
313 struct net_device *net_dev = i2400m->wimax_dev.net_dev;
314 size_t pending;
315 int rx_size;
316 struct sk_buff *rx_skb;
317
318 d_fnstart(4, dev, "(i2400mu %p)\n", i2400mu);
319 while (1) {
320 d_printf(2, dev, "TX: waiting for messages\n");
321 pending = 0;
322 wait_event_interruptible(
323 i2400mu->rx_wq,
324 (kthread_should_stop() /* check this first! */
325 || (pending = atomic_read(&i2400mu->rx_pending_count)))
326 );
327 if (kthread_should_stop())
328 break;
329 if (pending == 0)
330 continue;
331 rx_size = i2400mu->rx_size;
332 d_printf(2, dev, "RX: reading up to %d bytes\n", rx_size);
333 rx_skb = __netdev_alloc_skb(net_dev, rx_size, GFP_KERNEL);
334 if (rx_skb == NULL) {
335 dev_err(dev, "RX: can't allocate skb [%d bytes]\n",
336 rx_size);
337 msleep(50); /* give it some time? */
338 continue;
339 }
340
341 /* Receive the message with the payloads */
342 rx_skb = i2400mu_rx(i2400mu, rx_skb);
343 result = PTR_ERR(rx_skb);
344 if (IS_ERR(rx_skb))
345 goto out;
346 atomic_dec(&i2400mu->rx_pending_count);
347 if (rx_skb->len == 0) { /* some ignorable condition */
348 kfree_skb(rx_skb);
349 continue;
350 }
351
352 /* Deliver the message to the generic i2400m code */
353 i2400mu->rx_size_cnt++;
354 i2400mu->rx_size_acc += rx_skb->len;
355 result = i2400m_rx(i2400m, rx_skb);
356 if (result == -EIO
357 && edc_inc(&i2400mu->urb_edc,
358 EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
359 goto error_reset;
360 }
361
362 /* Maybe adjust RX buffer size */
363 i2400mu_rx_size_maybe_shrink(i2400mu);
364 }
365 result = 0;
366out:
367 d_fnend(4, dev, "(i2400mu %p) = %d\n", i2400mu, result);
368 return result;
369
370error_reset:
371 dev_err(dev, "RX: maximum errors in received buffer exceeded; "
372 "resetting device\n");
373 usb_queue_reset_device(i2400mu->usb_iface);
374 goto out;
375}
376
377
378/*
379 * Start reading from the device
380 *
381 * @i2400m: device instance
382 *
383 * Notify the RX thread that there is data pending.
384 */
385void i2400mu_rx_kick(struct i2400mu *i2400mu)
386{
387 struct i2400m *i2400m = &i2400mu->i2400m;
388 struct device *dev = &i2400mu->usb_iface->dev;
389
390 d_fnstart(3, dev, "(i2400mu %p)\n", i2400m);
391 atomic_inc(&i2400mu->rx_pending_count);
392 wake_up_all(&i2400mu->rx_wq);
393 d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
394}
395
396
397int i2400mu_rx_setup(struct i2400mu *i2400mu)
398{
399 int result = 0;
400 struct i2400m *i2400m = &i2400mu->i2400m;
401 struct device *dev = &i2400mu->usb_iface->dev;
402 struct wimax_dev *wimax_dev = &i2400m->wimax_dev;
403
404 i2400mu->rx_kthread = kthread_run(i2400mu_rxd, i2400mu, "%s-rx",
405 wimax_dev->name);
406 if (IS_ERR(i2400mu->rx_kthread)) {
407 result = PTR_ERR(i2400mu->rx_kthread);
408 dev_err(dev, "RX: cannot start thread: %d\n", result);
409 }
410 return result;
411}
412
413void i2400mu_rx_release(struct i2400mu *i2400mu)
414{
415 kthread_stop(i2400mu->rx_kthread);
416}
417
diff --git a/drivers/net/wimax/i2400m/usb-tx.c b/drivers/net/wimax/i2400m/usb-tx.c
new file mode 100644
index 000000000000..dfd893356f49
--- /dev/null
+++ b/drivers/net/wimax/i2400m/usb-tx.c
@@ -0,0 +1,229 @@
1/*
2 * Intel Wireless WiMAX Connection 2400m
3 * USB specific TX handling
4 *
5 *
6 * Copyright (C) 2007-2008 Intel Corporation. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * * Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * * Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 * * Neither the name of Intel Corporation nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
28 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
32 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 *
34 *
35 * Intel Corporation <linux-wimax@intel.com>
36 * Yanir Lubetkin <yanirx.lubetkin@intel.com>
37 * - Initial implementation
38 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
39 * - Split transport/device specific
40 *
41 *
42 * Takes the TX messages in the i2400m's driver TX FIFO and sends them
43 * to the device until there are no more.
44 *
45 * If we fail sending the message, we just drop it. There isn't much
46 * we can do at this point. We could also retry, but the USB stack has
47 * already retried and still failed, so there is not much of a
48 * point. As well, most of the traffic is network, which has recovery
49 * methods for dropped packets.
50 *
51 * For sending we just obtain a FIFO buffer to send, send it to the
52 * USB bulk out, tell the TX FIFO code we have sent it; query for
53 * another one, etc... until done.
54 *
55 * We use a thread so we can call usb_autopm_enable() and
56 * usb_autopm_disable() for each transaction; this way when the device
57 * goes idle, it will suspend. It also has less overhead than a
58 * dedicated workqueue, as it is being used for a single task.
59 *
60 * ROADMAP
61 *
62 * i2400mu_tx_setup()
63 * i2400mu_tx_release()
64 *
65 * i2400mu_bus_tx_kick() - Called by the tx.c code when there
66 * is new data in the FIFO.
67 * i2400mu_txd()
68 * i2400m_tx_msg_get()
69 * i2400m_tx_msg_sent()
70 */
71#include "i2400m-usb.h"
72
73
74#define D_SUBMODULE tx
75#include "usb-debug-levels.h"
76
77
78/*
79 * Get the next TX message in the TX FIFO and send it to the device
80 *
81 * Note that any iteration consumes a message to be sent, no matter if
82 * it succeeds or fails (we have no real way to retry or complain).
83 *
84 * Return: 0 if ok, < 0 errno code on hard error.
85 */
86static
87int i2400mu_tx(struct i2400mu *i2400mu, struct i2400m_msg_hdr *tx_msg,
88 size_t tx_msg_size)
89{
90 int result = 0;
91 struct i2400m *i2400m = &i2400mu->i2400m;
92 struct device *dev = &i2400mu->usb_iface->dev;
93 int usb_pipe, sent_size, do_autopm;
94 struct usb_endpoint_descriptor *epd;
95
96 d_fnstart(4, dev, "(i2400mu %p)\n", i2400mu);
97 do_autopm = atomic_read(&i2400mu->do_autopm);
98 result = do_autopm ?
99 usb_autopm_get_interface(i2400mu->usb_iface) : 0;
100 if (result < 0) {
101 dev_err(dev, "TX: can't get autopm: %d\n", result);
102 do_autopm = 0;
103 }
104 epd = usb_get_epd(i2400mu->usb_iface, I2400MU_EP_BULK_OUT);
105 usb_pipe = usb_sndbulkpipe(i2400mu->usb_dev, epd->bEndpointAddress);
106retry:
107 result = usb_bulk_msg(i2400mu->usb_dev, usb_pipe,
108 tx_msg, tx_msg_size, &sent_size, HZ);
109 usb_mark_last_busy(i2400mu->usb_dev);
110 switch (result) {
111 case 0:
112 if (sent_size != tx_msg_size) { /* Too short? drop it */
113 dev_err(dev, "TX: short write (%d B vs %zu "
114 "expected)\n", sent_size, tx_msg_size);
115 result = -EIO;
116 }
117 break;
118 case -EINVAL: /* while removing driver */
119 case -ENODEV: /* dev disconnect ... */
120 case -ENOENT: /* just ignore it */
121 case -ESHUTDOWN: /* and exit */
122 case -ECONNRESET:
123 result = -ESHUTDOWN;
124 break;
125 default: /* Some error? */
126 if (edc_inc(&i2400mu->urb_edc,
127 EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
128 dev_err(dev, "TX: maximum errors in URB "
129 "exceeded; resetting device\n");
130 usb_queue_reset_device(i2400mu->usb_iface);
131 } else {
132 dev_err(dev, "TX: cannot send URB; retrying. "
133 "tx_msg @%zu %zu B [%d sent]: %d\n",
134 (void *) tx_msg - i2400m->tx_buf,
135 tx_msg_size, sent_size, result);
136 goto retry;
137 }
138 }
139 if (do_autopm)
140 usb_autopm_put_interface(i2400mu->usb_iface);
141 d_fnend(4, dev, "(i2400mu %p) = result\n", i2400mu);
142 return result;
143}
144
145
146/*
147 * Get the next TX message in the TX FIFO and send it to the device
148 *
149 * Note we exit the loop if i2400mu_tx() fails; that funtion only
150 * fails on hard error (failing to tx a buffer not being one of them,
151 * see its doc).
152 *
153 * Return: 0
154 */
155static
156int i2400mu_txd(void *_i2400mu)
157{
158 int result = 0;
159 struct i2400mu *i2400mu = _i2400mu;
160 struct i2400m *i2400m = &i2400mu->i2400m;
161 struct device *dev = &i2400mu->usb_iface->dev;
162 struct i2400m_msg_hdr *tx_msg;
163 size_t tx_msg_size;
164
165 d_fnstart(4, dev, "(i2400mu %p)\n", i2400mu);
166
167 while (1) {
168 d_printf(2, dev, "TX: waiting for messages\n");
169 tx_msg = NULL;
170 wait_event_interruptible(
171 i2400mu->tx_wq,
172 (kthread_should_stop() /* check this first! */
173 || (tx_msg = i2400m_tx_msg_get(i2400m, &tx_msg_size)))
174 );
175 if (kthread_should_stop())
176 break;
177 WARN_ON(tx_msg == NULL); /* should not happen...*/
178 d_printf(2, dev, "TX: submitting %zu bytes\n", tx_msg_size);
179 d_dump(5, dev, tx_msg, tx_msg_size);
180 /* Yeah, we ignore errors ... not much we can do */
181 i2400mu_tx(i2400mu, tx_msg, tx_msg_size);
182 i2400m_tx_msg_sent(i2400m); /* ack it, advance the FIFO */
183 if (result < 0)
184 break;
185 }
186 d_fnend(4, dev, "(i2400mu %p) = %d\n", i2400mu, result);
187 return result;
188}
189
190
191/*
192 * i2400m TX engine notifies us that there is data in the FIFO ready
193 * for TX
194 *
195 * If there is a URB in flight, don't do anything; when it finishes,
196 * it will see there is data in the FIFO and send it. Else, just
197 * submit a write.
198 */
199void i2400mu_bus_tx_kick(struct i2400m *i2400m)
200{
201 struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
202 struct device *dev = &i2400mu->usb_iface->dev;
203
204 d_fnstart(3, dev, "(i2400m %p) = void\n", i2400m);
205 wake_up_all(&i2400mu->tx_wq);
206 d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
207}
208
209
210int i2400mu_tx_setup(struct i2400mu *i2400mu)
211{
212 int result = 0;
213 struct i2400m *i2400m = &i2400mu->i2400m;
214 struct device *dev = &i2400mu->usb_iface->dev;
215 struct wimax_dev *wimax_dev = &i2400m->wimax_dev;
216
217 i2400mu->tx_kthread = kthread_run(i2400mu_txd, i2400mu, "%s-tx",
218 wimax_dev->name);
219 if (IS_ERR(i2400mu->tx_kthread)) {
220 result = PTR_ERR(i2400mu->tx_kthread);
221 dev_err(dev, "TX: cannot start thread: %d\n", result);
222 }
223 return result;
224}
225
226void i2400mu_tx_release(struct i2400mu *i2400mu)
227{
228 kthread_stop(i2400mu->tx_kthread);
229}
generated by cgit v1.2.2 (git 2.25.0) at 2025-12-08 12:33:55 -0500