1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Intel Wireless WiMAX Connection 2400m
4  * Linux driver model glue for USB device, reset & fw upload
5  *
6  * Copyright (C) 2007-2008 Intel Corporation <linux-wimax@intel.com>
7  * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
8  * Yanir Lubetkin <yanirx.lubetkin@intel.com>
9  *
10  * See i2400m-usb.h for a general description of this driver.
11  *
12  * This file implements driver model glue, and hook ups for the
13  * generic driver to implement the bus-specific functions (device
14  * communication setup/tear down, firmware upload and resetting).
15  *
16  * ROADMAP
17  *
18  * i2400mu_probe()
19  *   alloc_netdev()...
20  *     i2400mu_netdev_setup()
21  *       i2400mu_init()
22  *       i2400m_netdev_setup()
23  *   i2400m_setup()...
24  *
25  * i2400mu_disconnect
26  *   i2400m_release()
27  *   free_netdev()
28  *
29  * i2400mu_suspend()
30  *   i2400m_cmd_enter_powersave()
31  *   i2400mu_notification_release()
32  *
33  * i2400mu_resume()
34  *   i2400mu_notification_setup()
35  *
36  * i2400mu_bus_dev_start()        Called by i2400m_dev_start() [who is
37  *   i2400mu_tx_setup()           called by i2400m_setup()]
38  *   i2400mu_rx_setup()
39  *   i2400mu_notification_setup()
40  *
41  * i2400mu_bus_dev_stop()         Called by i2400m_dev_stop() [who is
42  *   i2400mu_notification_release()  called by i2400m_release()]
43  *   i2400mu_rx_release()
44  *   i2400mu_tx_release()
45  *
46  * i2400mu_bus_reset()            Called by i2400m_reset
47  *   __i2400mu_reset()
48  *     __i2400mu_send_barker()
49  *   usb_reset_device()
50  */
51 #include "i2400m-usb.h"
52 #include <linux/wimax/i2400m.h>
53 #include <linux/debugfs.h>
54 #include <linux/slab.h>
55 #include <linux/module.h>
56 
57 
58 #define D_SUBMODULE usb
59 #include "usb-debug-levels.h"
60 
61 static char i2400mu_debug_params[128];
62 module_param_string(debug, i2400mu_debug_params, sizeof(i2400mu_debug_params),
63 		    0644);
64 MODULE_PARM_DESC(debug,
65 		 "String of space-separated NAME:VALUE pairs, where NAMEs "
66 		 "are the different debug submodules and VALUE are the "
67 		 "initial debug value to set.");
68 
69 /* Our firmware file name */
70 static const char *i2400mu_bus_fw_names_5x50[] = {
71 #define I2400MU_FW_FILE_NAME_v1_5 "i2400m-fw-usb-1.5.sbcf"
72 	I2400MU_FW_FILE_NAME_v1_5,
73 #define I2400MU_FW_FILE_NAME_v1_4 "i2400m-fw-usb-1.4.sbcf"
74 	I2400MU_FW_FILE_NAME_v1_4,
75 	NULL,
76 };
77 
78 
79 static const char *i2400mu_bus_fw_names_6050[] = {
80 #define I6050U_FW_FILE_NAME_v1_5 "i6050-fw-usb-1.5.sbcf"
81 	I6050U_FW_FILE_NAME_v1_5,
82 	NULL,
83 };
84 
85 
86 static
i2400mu_bus_dev_start(struct i2400m * i2400m)87 int i2400mu_bus_dev_start(struct i2400m *i2400m)
88 {
89 	int result;
90 	struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
91 	struct device *dev = &i2400mu->usb_iface->dev;
92 
93 	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
94 	result = i2400mu_tx_setup(i2400mu);
95 	if (result < 0)
96 		goto error_usb_tx_setup;
97 	result = i2400mu_rx_setup(i2400mu);
98 	if (result < 0)
99 		goto error_usb_rx_setup;
100 	result = i2400mu_notification_setup(i2400mu);
101 	if (result < 0)
102 		goto error_notif_setup;
103 	d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result);
104 	return result;
105 
106 error_notif_setup:
107 	i2400mu_rx_release(i2400mu);
108 error_usb_rx_setup:
109 	i2400mu_tx_release(i2400mu);
110 error_usb_tx_setup:
111 	d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
112 	return result;
113 }
114 
115 
116 static
i2400mu_bus_dev_stop(struct i2400m * i2400m)117 void i2400mu_bus_dev_stop(struct i2400m *i2400m)
118 {
119 	struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
120 	struct device *dev = &i2400mu->usb_iface->dev;
121 
122 	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
123 	i2400mu_notification_release(i2400mu);
124 	i2400mu_rx_release(i2400mu);
125 	i2400mu_tx_release(i2400mu);
126 	d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
127 }
128 
129 
130 /*
131  * Sends a barker buffer to the device
132  *
133  * This helper will allocate a kmalloced buffer and use it to transmit
134  * (then free it). Reason for this is that other arches cannot use
135  * stack/vmalloc/text areas for DMA transfers.
136  *
137  * Error recovery here is simpler: anything is considered a hard error
138  * and will move the reset code to use a last-resort bus-based reset.
139  */
140 static
__i2400mu_send_barker(struct i2400mu * i2400mu,const __le32 * barker,size_t barker_size,unsigned endpoint)141 int __i2400mu_send_barker(struct i2400mu *i2400mu,
142 			  const __le32 *barker,
143 			  size_t barker_size,
144 			  unsigned endpoint)
145 {
146 	struct usb_endpoint_descriptor *epd = NULL;
147 	int pipe, actual_len, ret;
148 	struct device *dev = &i2400mu->usb_iface->dev;
149 	void *buffer;
150 	int do_autopm = 1;
151 
152 	ret = usb_autopm_get_interface(i2400mu->usb_iface);
153 	if (ret < 0) {
154 		dev_err(dev, "RESET: can't get autopm: %d\n", ret);
155 		do_autopm = 0;
156 	}
157 	ret = -ENOMEM;
158 	buffer = kmalloc(barker_size, GFP_KERNEL);
159 	if (buffer == NULL)
160 		goto error_kzalloc;
161 	epd = usb_get_epd(i2400mu->usb_iface, endpoint);
162 	pipe = usb_sndbulkpipe(i2400mu->usb_dev, epd->bEndpointAddress);
163 	memcpy(buffer, barker, barker_size);
164 retry:
165 	ret = usb_bulk_msg(i2400mu->usb_dev, pipe, buffer, barker_size,
166 			   &actual_len, 200);
167 	switch (ret) {
168 	case 0:
169 		if (actual_len != barker_size) {	/* Too short? drop it */
170 			dev_err(dev, "E: %s: short write (%d B vs %zu "
171 				"expected)\n",
172 				__func__, actual_len, barker_size);
173 			ret = -EIO;
174 		}
175 		break;
176 	case -EPIPE:
177 		/*
178 		 * Stall -- maybe the device is choking with our
179 		 * requests. Clear it and give it some time. If they
180 		 * happen to often, it might be another symptom, so we
181 		 * reset.
182 		 *
183 		 * No error handling for usb_clear_halt(0; if it
184 		 * works, the retry works; if it fails, this switch
185 		 * does the error handling for us.
186 		 */
187 		if (edc_inc(&i2400mu->urb_edc,
188 			    10 * EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
189 			dev_err(dev, "E: %s: too many stalls in "
190 				"URB; resetting device\n", __func__);
191 			usb_queue_reset_device(i2400mu->usb_iface);
192 			/* fallthrough */
193 		} else {
194 			usb_clear_halt(i2400mu->usb_dev, pipe);
195 			msleep(10);	/* give the device some time */
196 			goto retry;
197 		}
198 		fallthrough;
199 	case -EINVAL:			/* while removing driver */
200 	case -ENODEV:			/* dev disconnect ... */
201 	case -ENOENT:			/* just ignore it */
202 	case -ESHUTDOWN:		/* and exit */
203 	case -ECONNRESET:
204 		ret = -ESHUTDOWN;
205 		break;
206 	default:			/* Some error? */
207 		if (edc_inc(&i2400mu->urb_edc,
208 			    EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
209 			dev_err(dev, "E: %s: maximum errors in URB "
210 				"exceeded; resetting device\n",
211 				__func__);
212 			usb_queue_reset_device(i2400mu->usb_iface);
213 		} else {
214 			dev_warn(dev, "W: %s: cannot send URB: %d\n",
215 				 __func__, ret);
216 			goto retry;
217 		}
218 	}
219 	kfree(buffer);
220 error_kzalloc:
221 	if (do_autopm)
222 		usb_autopm_put_interface(i2400mu->usb_iface);
223 	return ret;
224 }
225 
226 
227 /*
228  * Reset a device at different levels (warm, cold or bus)
229  *
230  * @i2400m: device descriptor
231  * @reset_type: soft, warm or bus reset (I2400M_RT_WARM/SOFT/BUS)
232  *
233  * Warm and cold resets get a USB reset if they fail.
234  *
235  * Warm reset:
236  *
237  * The device will be fully reset internally, but won't be
238  * disconnected from the USB bus (so no reenumeration will
239  * happen). Firmware upload will be necessary.
240  *
241  * The device will send a reboot barker in the notification endpoint
242  * that will trigger the driver to reinitialize the state
243  * automatically from notif.c:i2400m_notification_grok() into
244  * i2400m_dev_bootstrap_delayed().
245  *
246  * Cold and bus (USB) reset:
247  *
248  * The device will be fully reset internally, disconnected from the
249  * USB bus an a reenumeration will happen. Firmware upload will be
250  * necessary. Thus, we don't do any locking or struct
251  * reinitialization, as we are going to be fully disconnected and
252  * reenumerated.
253  *
254  * Note we need to return -ENODEV if a warm reset was requested and we
255  * had to resort to a bus reset. See i2400m_op_reset(), wimax_reset()
256  * and wimax_dev->op_reset.
257  *
258  * WARNING: no driver state saved/fixed
259  */
260 static
i2400mu_bus_reset(struct i2400m * i2400m,enum i2400m_reset_type rt)261 int i2400mu_bus_reset(struct i2400m *i2400m, enum i2400m_reset_type rt)
262 {
263 	int result;
264 	struct i2400mu *i2400mu =
265 		container_of(i2400m, struct i2400mu, i2400m);
266 	struct device *dev = i2400m_dev(i2400m);
267 	static const __le32 i2400m_WARM_BOOT_BARKER[4] = {
268 		cpu_to_le32(I2400M_WARM_RESET_BARKER),
269 		cpu_to_le32(I2400M_WARM_RESET_BARKER),
270 		cpu_to_le32(I2400M_WARM_RESET_BARKER),
271 		cpu_to_le32(I2400M_WARM_RESET_BARKER),
272 	};
273 	static const __le32 i2400m_COLD_BOOT_BARKER[4] = {
274 		cpu_to_le32(I2400M_COLD_RESET_BARKER),
275 		cpu_to_le32(I2400M_COLD_RESET_BARKER),
276 		cpu_to_le32(I2400M_COLD_RESET_BARKER),
277 		cpu_to_le32(I2400M_COLD_RESET_BARKER),
278 	};
279 
280 	d_fnstart(3, dev, "(i2400m %p rt %u)\n", i2400m, rt);
281 	if (rt == I2400M_RT_WARM)
282 		result = __i2400mu_send_barker(
283 			i2400mu, i2400m_WARM_BOOT_BARKER,
284 			sizeof(i2400m_WARM_BOOT_BARKER),
285 			i2400mu->endpoint_cfg.bulk_out);
286 	else if (rt == I2400M_RT_COLD)
287 		result = __i2400mu_send_barker(
288 			i2400mu, i2400m_COLD_BOOT_BARKER,
289 			sizeof(i2400m_COLD_BOOT_BARKER),
290 			i2400mu->endpoint_cfg.reset_cold);
291 	else if (rt == I2400M_RT_BUS) {
292 		result = usb_reset_device(i2400mu->usb_dev);
293 		switch (result) {
294 		case 0:
295 		case -EINVAL:	/* device is gone */
296 		case -ENODEV:
297 		case -ENOENT:
298 		case -ESHUTDOWN:
299 			result = 0;
300 			break;	/* We assume the device is disconnected */
301 		default:
302 			dev_err(dev, "USB reset failed (%d), giving up!\n",
303 				result);
304 		}
305 	} else {
306 		result = -EINVAL;	/* shut gcc up in certain arches */
307 		BUG();
308 	}
309 	if (result < 0
310 	    && result != -EINVAL	/* device is gone */
311 	    && rt != I2400M_RT_BUS) {
312 		/*
313 		 * Things failed -- resort to lower level reset, that
314 		 * we queue in another context; the reason for this is
315 		 * that the pre and post reset functionality requires
316 		 * the i2400m->init_mutex; RT_WARM and RT_COLD can
317 		 * come from areas where i2400m->init_mutex is taken.
318 		 */
319 		dev_err(dev, "%s reset failed (%d); trying USB reset\n",
320 			rt == I2400M_RT_WARM ? "warm" : "cold", result);
321 		usb_queue_reset_device(i2400mu->usb_iface);
322 		result = -ENODEV;
323 	}
324 	d_fnend(3, dev, "(i2400m %p rt %u) = %d\n", i2400m, rt, result);
325 	return result;
326 }
327 
i2400mu_get_drvinfo(struct net_device * net_dev,struct ethtool_drvinfo * info)328 static void i2400mu_get_drvinfo(struct net_device *net_dev,
329                                 struct ethtool_drvinfo *info)
330 {
331 	struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
332 	struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
333 	struct usb_device *udev = i2400mu->usb_dev;
334 
335 	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
336 	strlcpy(info->fw_version, i2400m->fw_name ? : "",
337 		sizeof(info->fw_version));
338 	usb_make_path(udev, info->bus_info, sizeof(info->bus_info));
339 }
340 
341 static const struct ethtool_ops i2400mu_ethtool_ops = {
342 	.get_drvinfo = i2400mu_get_drvinfo,
343 	.get_link = ethtool_op_get_link,
344 };
345 
346 static
i2400mu_netdev_setup(struct net_device * net_dev)347 void i2400mu_netdev_setup(struct net_device *net_dev)
348 {
349 	struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
350 	struct i2400mu *i2400mu = container_of(i2400m, struct i2400mu, i2400m);
351 	i2400mu_init(i2400mu);
352 	i2400m_netdev_setup(net_dev);
353 	net_dev->ethtool_ops = &i2400mu_ethtool_ops;
354 }
355 
356 
357 /*
358  * Debug levels control; see debug.h
359  */
360 struct d_level D_LEVEL[] = {
361 	D_SUBMODULE_DEFINE(usb),
362 	D_SUBMODULE_DEFINE(fw),
363 	D_SUBMODULE_DEFINE(notif),
364 	D_SUBMODULE_DEFINE(rx),
365 	D_SUBMODULE_DEFINE(tx),
366 };
367 size_t D_LEVEL_SIZE = ARRAY_SIZE(D_LEVEL);
368 
369 static
i2400mu_debugfs_add(struct i2400mu * i2400mu)370 void i2400mu_debugfs_add(struct i2400mu *i2400mu)
371 {
372 	struct dentry *dentry = i2400mu->i2400m.wimax_dev.debugfs_dentry;
373 
374 	dentry = debugfs_create_dir("i2400m-usb", dentry);
375 	i2400mu->debugfs_dentry = dentry;
376 
377 	d_level_register_debugfs("dl_", usb, dentry);
378 	d_level_register_debugfs("dl_", fw, dentry);
379 	d_level_register_debugfs("dl_", notif, dentry);
380 	d_level_register_debugfs("dl_", rx, dentry);
381 	d_level_register_debugfs("dl_", tx, dentry);
382 
383 	/* Don't touch these if you don't know what you are doing */
384 	debugfs_create_u8("rx_size_auto_shrink", 0600, dentry,
385 			  &i2400mu->rx_size_auto_shrink);
386 
387 	debugfs_create_size_t("rx_size", 0600, dentry, &i2400mu->rx_size);
388 }
389 
390 
391 static struct device_type i2400mu_type = {
392 	.name	= "wimax",
393 };
394 
395 /*
396  * Probe a i2400m interface and register it
397  *
398  * @iface:   USB interface to link to
399  * @id:      USB class/subclass/protocol id
400  * @returns: 0 if ok, < 0 errno code on error.
401  *
402  * Alloc a net device, initialize the bus-specific details and then
403  * calls the bus-generic initialization routine. That will register
404  * the wimax and netdev devices, upload the firmware [using
405  * _bus_bm_*()], call _bus_dev_start() to finalize the setup of the
406  * communication with the device and then will start to talk to it to
407  * finnish setting it up.
408  */
409 static
i2400mu_probe(struct usb_interface * iface,const struct usb_device_id * id)410 int i2400mu_probe(struct usb_interface *iface,
411 		  const struct usb_device_id *id)
412 {
413 	int result;
414 	struct net_device *net_dev;
415 	struct device *dev = &iface->dev;
416 	struct i2400m *i2400m;
417 	struct i2400mu *i2400mu;
418 	struct usb_device *usb_dev = interface_to_usbdev(iface);
419 
420 	if (iface->cur_altsetting->desc.bNumEndpoints < 4)
421 		return -ENODEV;
422 
423 	if (usb_dev->speed != USB_SPEED_HIGH)
424 		dev_err(dev, "device not connected as high speed\n");
425 
426 	/* Allocate instance [calls i2400m_netdev_setup() on it]. */
427 	result = -ENOMEM;
428 	net_dev = alloc_netdev(sizeof(*i2400mu), "wmx%d", NET_NAME_UNKNOWN,
429 			       i2400mu_netdev_setup);
430 	if (net_dev == NULL) {
431 		dev_err(dev, "no memory for network device instance\n");
432 		goto error_alloc_netdev;
433 	}
434 	SET_NETDEV_DEV(net_dev, dev);
435 	SET_NETDEV_DEVTYPE(net_dev, &i2400mu_type);
436 	i2400m = net_dev_to_i2400m(net_dev);
437 	i2400mu = container_of(i2400m, struct i2400mu, i2400m);
438 	i2400m->wimax_dev.net_dev = net_dev;
439 	i2400mu->usb_dev = usb_get_dev(usb_dev);
440 	i2400mu->usb_iface = iface;
441 	usb_set_intfdata(iface, i2400mu);
442 
443 	i2400m->bus_tx_block_size = I2400MU_BLK_SIZE;
444 	/*
445 	 * Room required in the Tx queue for USB message to accommodate
446 	 * a smallest payload while allocating header space is 16 bytes.
447 	 * Adding this room  for the new tx message increases the
448 	 * possibilities of including any payload with size <= 16 bytes.
449 	 */
450 	i2400m->bus_tx_room_min = I2400MU_BLK_SIZE;
451 	i2400m->bus_pl_size_max = I2400MU_PL_SIZE_MAX;
452 	i2400m->bus_setup = NULL;
453 	i2400m->bus_dev_start = i2400mu_bus_dev_start;
454 	i2400m->bus_dev_stop = i2400mu_bus_dev_stop;
455 	i2400m->bus_release = NULL;
456 	i2400m->bus_tx_kick = i2400mu_bus_tx_kick;
457 	i2400m->bus_reset = i2400mu_bus_reset;
458 	i2400m->bus_bm_retries = I2400M_USB_BOOT_RETRIES;
459 	i2400m->bus_bm_cmd_send = i2400mu_bus_bm_cmd_send;
460 	i2400m->bus_bm_wait_for_ack = i2400mu_bus_bm_wait_for_ack;
461 	i2400m->bus_bm_mac_addr_impaired = 0;
462 
463 	switch (id->idProduct) {
464 	case USB_DEVICE_ID_I6050:
465 	case USB_DEVICE_ID_I6050_2:
466 	case USB_DEVICE_ID_I6150:
467 	case USB_DEVICE_ID_I6150_2:
468 	case USB_DEVICE_ID_I6150_3:
469 	case USB_DEVICE_ID_I6250:
470 		i2400mu->i6050 = 1;
471 		break;
472 	default:
473 		break;
474 	}
475 
476 	if (i2400mu->i6050) {
477 		i2400m->bus_fw_names = i2400mu_bus_fw_names_6050;
478 		i2400mu->endpoint_cfg.bulk_out = 0;
479 		i2400mu->endpoint_cfg.notification = 3;
480 		i2400mu->endpoint_cfg.reset_cold = 2;
481 		i2400mu->endpoint_cfg.bulk_in = 1;
482 	} else {
483 		i2400m->bus_fw_names = i2400mu_bus_fw_names_5x50;
484 		i2400mu->endpoint_cfg.bulk_out = 0;
485 		i2400mu->endpoint_cfg.notification = 1;
486 		i2400mu->endpoint_cfg.reset_cold = 2;
487 		i2400mu->endpoint_cfg.bulk_in = 3;
488 	}
489 #ifdef CONFIG_PM
490 	iface->needs_remote_wakeup = 1;		/* autosuspend (15s delay) */
491 	device_init_wakeup(dev, 1);
492 	pm_runtime_set_autosuspend_delay(&usb_dev->dev, 15000);
493 	usb_enable_autosuspend(usb_dev);
494 #endif
495 
496 	result = i2400m_setup(i2400m, I2400M_BRI_MAC_REINIT);
497 	if (result < 0) {
498 		dev_err(dev, "cannot setup device: %d\n", result);
499 		goto error_setup;
500 	}
501 	i2400mu_debugfs_add(i2400mu);
502 	return 0;
503 
504 error_setup:
505 	usb_set_intfdata(iface, NULL);
506 	usb_put_dev(i2400mu->usb_dev);
507 	free_netdev(net_dev);
508 error_alloc_netdev:
509 	return result;
510 }
511 
512 
513 /*
514  * Disconnect a i2400m from the system.
515  *
516  * i2400m_stop() has been called before, so al the rx and tx contexts
517  * have been taken down already. Make sure the queue is stopped,
518  * unregister netdev and i2400m, free and kill.
519  */
520 static
i2400mu_disconnect(struct usb_interface * iface)521 void i2400mu_disconnect(struct usb_interface *iface)
522 {
523 	struct i2400mu *i2400mu = usb_get_intfdata(iface);
524 	struct i2400m *i2400m = &i2400mu->i2400m;
525 	struct net_device *net_dev = i2400m->wimax_dev.net_dev;
526 	struct device *dev = &iface->dev;
527 
528 	d_fnstart(3, dev, "(iface %p i2400m %p)\n", iface, i2400m);
529 
530 	debugfs_remove_recursive(i2400mu->debugfs_dentry);
531 	i2400m_release(i2400m);
532 	usb_set_intfdata(iface, NULL);
533 	usb_put_dev(i2400mu->usb_dev);
534 	free_netdev(net_dev);
535 	d_fnend(3, dev, "(iface %p i2400m %p) = void\n", iface, i2400m);
536 }
537 
538 
539 /*
540  * Get the device ready for USB port or system standby and hibernation
541  *
542  * USB port and system standby are handled the same.
543  *
544  * When the system hibernates, the USB device is powered down and then
545  * up, so we don't really have to do much here, as it will be seen as
546  * a reconnect. Still for simplicity we consider this case the same as
547  * suspend, so that the device has a chance to do notify the base
548  * station (if connected).
549  *
550  * So at the end, the three cases require common handling.
551  *
552  * If at the time of this call the device's firmware is not loaded,
553  * nothing has to be done. Note we can be "loose" about not reading
554  * i2400m->updown under i2400m->init_mutex. If it happens to change
555  * inmediately, other parts of the call flow will fail and effectively
556  * catch it.
557  *
558  * If the firmware is loaded, we need to:
559  *
560  *  - tell the device to go into host interface power save mode, wait
561  *    for it to ack
562  *
563  *    This is quite more interesting than it is; we need to execute a
564  *    command, but this time, we don't want the code in usb-{tx,rx}.c
565  *    to call the usb_autopm_get/put_interface() barriers as it'd
566  *    deadlock, so we need to decrement i2400mu->do_autopm, that acts
567  *    as a poor man's semaphore. Ugly, but it works.
568  *
569  *    As well, the device might refuse going to sleep for whichever
570  *    reason. In this case we just fail. For system suspend/hibernate,
571  *    we *can't* fail. We check PMSG_IS_AUTO to see if the
572  *    suspend call comes from the USB stack or from the system and act
573  *    in consequence.
574  *
575  *  - stop the notification endpoint polling
576  */
577 static
i2400mu_suspend(struct usb_interface * iface,pm_message_t pm_msg)578 int i2400mu_suspend(struct usb_interface *iface, pm_message_t pm_msg)
579 {
580 	int result = 0;
581 	struct device *dev = &iface->dev;
582 	struct i2400mu *i2400mu = usb_get_intfdata(iface);
583 	unsigned is_autosuspend = 0;
584 	struct i2400m *i2400m = &i2400mu->i2400m;
585 
586 #ifdef CONFIG_PM
587 	if (PMSG_IS_AUTO(pm_msg))
588 		is_autosuspend = 1;
589 #endif
590 
591 	d_fnstart(3, dev, "(iface %p pm_msg %u)\n", iface, pm_msg.event);
592 	rmb();		/* see i2400m->updown's documentation  */
593 	if (i2400m->updown == 0)
594 		goto no_firmware;
595 	if (i2400m->state == I2400M_SS_DATA_PATH_CONNECTED && is_autosuspend) {
596 		/* ugh -- the device is connected and this suspend
597 		 * request is an autosuspend one (not a system standby
598 		 * / hibernate).
599 		 *
600 		 * The only way the device can go to standby is if the
601 		 * link with the base station is in IDLE mode; that
602 		 * were the case, we'd be in status
603 		 * I2400M_SS_CONNECTED_IDLE. But we are not.
604 		 *
605 		 * If we *tell* him to go power save now, it'll reset
606 		 * as a precautionary measure, so if this is an
607 		 * autosuspend thing, say no and it'll come back
608 		 * later, when the link is IDLE
609 		 */
610 		result = -EBADF;
611 		d_printf(1, dev, "fw up, link up, not-idle, autosuspend: "
612 			 "not entering powersave\n");
613 		goto error_not_now;
614 	}
615 	d_printf(1, dev, "fw up: entering powersave\n");
616 	atomic_dec(&i2400mu->do_autopm);
617 	result = i2400m_cmd_enter_powersave(i2400m);
618 	atomic_inc(&i2400mu->do_autopm);
619 	if (result < 0 && !is_autosuspend) {
620 		/* System suspend, can't fail */
621 		dev_err(dev, "failed to suspend, will reset on resume\n");
622 		result = 0;
623 	}
624 	if (result < 0)
625 		goto error_enter_powersave;
626 	i2400mu_notification_release(i2400mu);
627 	d_printf(1, dev, "powersave requested\n");
628 error_enter_powersave:
629 error_not_now:
630 no_firmware:
631 	d_fnend(3, dev, "(iface %p pm_msg %u) = %d\n",
632 		iface, pm_msg.event, result);
633 	return result;
634 }
635 
636 
637 static
i2400mu_resume(struct usb_interface * iface)638 int i2400mu_resume(struct usb_interface *iface)
639 {
640 	int ret = 0;
641 	struct device *dev = &iface->dev;
642 	struct i2400mu *i2400mu = usb_get_intfdata(iface);
643 	struct i2400m *i2400m = &i2400mu->i2400m;
644 
645 	d_fnstart(3, dev, "(iface %p)\n", iface);
646 	rmb();		/* see i2400m->updown's documentation  */
647 	if (i2400m->updown == 0) {
648 		d_printf(1, dev, "fw was down, no resume needed\n");
649 		goto out;
650 	}
651 	d_printf(1, dev, "fw was up, resuming\n");
652 	i2400mu_notification_setup(i2400mu);
653 	/* USB has flow control, so we don't need to give it time to
654 	 * come back; otherwise, we'd use something like a get-state
655 	 * command... */
656 out:
657 	d_fnend(3, dev, "(iface %p) = %d\n", iface, ret);
658 	return ret;
659 }
660 
661 
662 static
i2400mu_reset_resume(struct usb_interface * iface)663 int i2400mu_reset_resume(struct usb_interface *iface)
664 {
665 	int result;
666 	struct device *dev = &iface->dev;
667 	struct i2400mu *i2400mu = usb_get_intfdata(iface);
668 	struct i2400m *i2400m = &i2400mu->i2400m;
669 
670 	d_fnstart(3, dev, "(iface %p)\n", iface);
671 	result = i2400m_dev_reset_handle(i2400m, "device reset on resume");
672 	d_fnend(3, dev, "(iface %p) = %d\n", iface, result);
673 	return result < 0 ? result : 0;
674 }
675 
676 
677 /*
678  * Another driver or user space is triggering a reset on the device
679  * which contains the interface passed as an argument. Cease IO and
680  * save any device state you need to restore.
681  *
682  * If you need to allocate memory here, use GFP_NOIO or GFP_ATOMIC, if
683  * you are in atomic context.
684  */
685 static
i2400mu_pre_reset(struct usb_interface * iface)686 int i2400mu_pre_reset(struct usb_interface *iface)
687 {
688 	struct i2400mu *i2400mu = usb_get_intfdata(iface);
689 	return i2400m_pre_reset(&i2400mu->i2400m);
690 }
691 
692 
693 /*
694  * The reset has completed.  Restore any saved device state and begin
695  * using the device again.
696  *
697  * If you need to allocate memory here, use GFP_NOIO or GFP_ATOMIC, if
698  * you are in atomic context.
699  */
700 static
i2400mu_post_reset(struct usb_interface * iface)701 int i2400mu_post_reset(struct usb_interface *iface)
702 {
703 	struct i2400mu *i2400mu = usb_get_intfdata(iface);
704 	return i2400m_post_reset(&i2400mu->i2400m);
705 }
706 
707 
708 static
709 struct usb_device_id i2400mu_id_table[] = {
710 	{ USB_DEVICE(0x8086, USB_DEVICE_ID_I6050) },
711 	{ USB_DEVICE(0x8086, USB_DEVICE_ID_I6050_2) },
712 	{ USB_DEVICE(0x8087, USB_DEVICE_ID_I6150) },
713 	{ USB_DEVICE(0x8087, USB_DEVICE_ID_I6150_2) },
714 	{ USB_DEVICE(0x8087, USB_DEVICE_ID_I6150_3) },
715 	{ USB_DEVICE(0x8086, USB_DEVICE_ID_I6250) },
716 	{ USB_DEVICE(0x8086, 0x0181) },
717 	{ USB_DEVICE(0x8086, 0x1403) },
718 	{ USB_DEVICE(0x8086, 0x1405) },
719 	{ USB_DEVICE(0x8086, 0x0180) },
720 	{ USB_DEVICE(0x8086, 0x0182) },
721 	{ USB_DEVICE(0x8086, 0x1406) },
722 	{ USB_DEVICE(0x8086, 0x1403) },
723 	{ },
724 };
725 MODULE_DEVICE_TABLE(usb, i2400mu_id_table);
726 
727 
728 static
729 struct usb_driver i2400mu_driver = {
730 	.name = KBUILD_MODNAME,
731 	.suspend = i2400mu_suspend,
732 	.resume = i2400mu_resume,
733 	.reset_resume = i2400mu_reset_resume,
734 	.probe = i2400mu_probe,
735 	.disconnect = i2400mu_disconnect,
736 	.pre_reset = i2400mu_pre_reset,
737 	.post_reset = i2400mu_post_reset,
738 	.id_table = i2400mu_id_table,
739 	.supports_autosuspend = 1,
740 };
741 
742 static
i2400mu_driver_init(void)743 int __init i2400mu_driver_init(void)
744 {
745 	d_parse_params(D_LEVEL, D_LEVEL_SIZE, i2400mu_debug_params,
746 		       "i2400m_usb.debug");
747 	return usb_register(&i2400mu_driver);
748 }
749 module_init(i2400mu_driver_init);
750 
751 
752 static
i2400mu_driver_exit(void)753 void __exit i2400mu_driver_exit(void)
754 {
755 	usb_deregister(&i2400mu_driver);
756 }
757 module_exit(i2400mu_driver_exit);
758 
759 MODULE_AUTHOR("Intel Corporation <linux-wimax@intel.com>");
760 MODULE_DESCRIPTION("Driver for USB based Intel Wireless WiMAX Connection 2400M "
761 		   "(5x50 & 6050)");
762 MODULE_LICENSE("GPL");
763 MODULE_FIRMWARE(I2400MU_FW_FILE_NAME_v1_5);
764 MODULE_FIRMWARE(I6050U_FW_FILE_NAME_v1_5);
765