xref: /netbsd-src/sys/dev/usb/usbnet.h (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: usbnet.h,v 1.22 2021/12/11 19:24:21 mrg Exp $	*/
2 
3 /*
4  * Copyright (c) 2019 Matthew R. Green
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #ifndef _DEV_USB_USBNET_H
30 #define _DEV_USB_USBNET_H
31 
32 /*
33  * Common code/data shared by all USB ethernet drivers (using these routines.)
34  *
35  * This framework provides the following features for USB ethernet drivers:
36  *
37  * - USB endpoint pipe handling
38  * - rx and tx chain handling
39  * - generic handlers or support for several struct ifnet callbacks
40  * - MII bus locking
41  * - interrupt handling
42  * - partial autoconf handling
43  *
44  * Consumers of this interface need to:
45  *
46  * - replace most softc members with "struct usbnet" usage, in particular
47  *   use usbnet pointer for ifp->if_softc, and device_private (real softc
48  *   can be stored in un_sc member)
49  * - use MII bus lock / access methods
50  * - usbnet_attach() to initialise and allocate rx/tx chains
51  * - usbnet_attach_ifp() to attach the interface, and either ether_ifattach()
52  *   for ethernet devices, or if_alloc_sadl()/bpf_attach() pair otherwise.
53  * - usbnet_detach() to clean them up
54  * - usbnet_activate() for autoconf
55  * - interface ioctl and start have direct frontends with callbacks for
56  *   device specific handling:
57  *   - ioctl can use either a device-specific override (useful for special
58  *     cases), but provides a normal handler with callback to handle
59  *     ENETRESET conditions that should be sufficient for most users
60  *   - start uses usbnet transmit prepare callback (uno_tx_prepare)
61  * - interface init and stop have helper functions
62  *   - device specific init should use usbnet_init_rx_tx() to open pipes
63  *     to the device and setup the rx/tx chains for use after any device
64  *     specific setup
65  *   - usbnet_stop() must be called with the un_lock held, and will
66  *     call the device-specific usbnet stop callback, which enables the
67  *     standard init calls stop idiom.
68  * - interrupt handling:
69  *   - for rx, usbnet_init_rx_tx() will enable the receive pipes and
70  *     call the rx_loop callback to handle device specific processing of
71  *     packets, which can use usbnet_enqueue() to provide data to the
72  *     higher layers
73  *   - for tx, usbnet_start (if_start) will pull entries out of the
74  *     transmit queue and use the transmit prepare callback (uno_tx_prepare)
75  *     for the given mbuf.  the usb callback will use usbnet_txeof() for
76  *     the transmit completion function (internal to usbnet)
77  *   - there is special interrupt pipe handling
78  * - timer/tick:
79  *   - the uno_tick callback will be called once a second if present.
80  */
81 
82 #include <sys/device.h>
83 #include <sys/mbuf.h>
84 #include <sys/rndsource.h>
85 #include <sys/mutex.h>
86 #include <sys/module.h>
87 
88 #include <net/bpf.h>
89 #include <net/if.h>
90 #include <net/if_arp.h>
91 #include <net/if_dl.h>
92 #include <net/if_ether.h>
93 #include <net/if_media.h>
94 
95 #include <dev/mii/mii.h>
96 #include <dev/mii/miivar.h>
97 
98 #include <dev/usb/usb.h>
99 #include <dev/usb/usbdi.h>
100 #include <dev/usb/usbdivar.h>
101 #include <dev/usb/usbdi_util.h>
102 #include <dev/usb/usbdevs.h>
103 
104 /*
105  * Per-transfer data.
106  *
107  * Front-end must set un_rx_list_cnt and un_tx_list_cnt before
108  * calling usbnet_attach(), and then call usbnet_rx_tx_init()
109  * which will allocate the chain arrays, and must be NULL to
110  * indicate the first call.
111  */
112 struct usbnet;
113 struct usbnet_chain {
114 	struct usbnet		*unc_un;
115 	struct usbd_xfer	*unc_xfer;
116 	uint8_t			*unc_buf;
117 };
118 
119 /*
120  * Extend this as necessary.  axe(4) claims to want 6 total, but
121  * does not implement them.
122  */
123 enum usbnet_ep {
124 	USBNET_ENDPT_RX,
125 	USBNET_ENDPT_TX,
126 	USBNET_ENDPT_INTR,
127 	USBNET_ENDPT_MAX,
128 };
129 
130 /* Interface stop callback. */
131 typedef void (*usbnet_stop_cb)(struct ifnet *, int);
132 /* Interface ioctl callback. */
133 typedef int (*usbnet_ioctl_cb)(struct ifnet *, u_long, void *);
134 /* Initialise device callback. */
135 typedef int (*usbnet_init_cb)(struct ifnet *);
136 
137 /* MII read register callback. */
138 typedef int (*usbnet_mii_read_reg_cb)(struct usbnet *, int reg,
139 				      int phy, uint16_t *val);
140 /* MII write register callback. */
141 typedef int (*usbnet_mii_write_reg_cb)(struct usbnet *, int reg,
142 				       int phy, uint16_t val);
143 /* MII status change callback. */
144 typedef void (*usbnet_mii_statchg_cb)(struct ifnet *);
145 
146 /* Prepare packet to send callback, returns length. */
147 typedef unsigned (*usbnet_tx_prepare_cb)(struct usbnet *, struct mbuf *,
148 					 struct usbnet_chain *);
149 /* Receive some packets callback. */
150 typedef void (*usbnet_rx_loop_cb)(struct usbnet *, struct usbnet_chain *,
151 				  uint32_t);
152 /* Tick callback. */
153 typedef void (*usbnet_tick_cb)(struct usbnet *);
154 /* Interrupt pipe callback. */
155 typedef void (*usbnet_intr_cb)(struct usbnet *, usbd_status);
156 
157 /*
158  * LOCKING
159  * =======
160  *
161  * The following annotations indicate which locks are held when
162  * usbnet_ops functions are invoked:
163  *
164  * I -> IFNET_LOCK (if_ioctl_lock)
165  * C -> CORE_LOCK (usbnet core_lock)
166  * T -> TX_LOCK (usbnet tx_lock)
167  * R -> RX_LOCK (usbnet rx_lock)
168  * n -> no locks held
169  *
170  * Note that when CORE_LOCK is held, IFNET_LOCK may or may not also
171  * be held.
172  *
173  * Note that the IFNET_LOCK **may not be held** for some ioctl
174  * operations (add/delete multicast addresses, for example).
175  *
176  * Busy reference counts are maintained across calls to: uno_stop,
177  * uno_read_reg, uno_write_reg, uno_statchg, and uno_tick.
178  */
179 struct usbnet_ops {
180 	usbnet_stop_cb		uno_stop;		/* C */
181 	usbnet_ioctl_cb		uno_ioctl;		/* I (maybe) */
182 	usbnet_ioctl_cb		uno_override_ioctl;	/* I (maybe) */
183 	usbnet_init_cb		uno_init;		/* I */
184 	usbnet_mii_read_reg_cb	uno_read_reg;		/* C */
185 	usbnet_mii_write_reg_cb uno_write_reg;		/* C */
186 	usbnet_mii_statchg_cb	uno_statchg;		/* C */
187 	usbnet_tx_prepare_cb	uno_tx_prepare;		/* T */
188 	usbnet_rx_loop_cb	uno_rx_loop;		/* R */
189 	usbnet_tick_cb		uno_tick;		/* n */
190 	usbnet_intr_cb		uno_intr;		/* n */
191 };
192 
193 /*
194  * USB interrupt pipe support.  Use this if usbd_open_pipe_intr() should
195  * be used for the interrupt pipe.
196  */
197 struct usbnet_intr {
198 	/*
199 	 * Point un_intr to this structure to use usbd_open_pipe_intr() not
200 	 * usbd_open_pipe() for USBNET_ENDPT_INTR, with this buffer, size,
201 	 * and interval.
202 	 */
203 	void			*uni_buf;
204 	unsigned		uni_bufsz;
205 	unsigned		uni_interval;
206 };
207 
208 /*
209  * Structure to setup MII.  Use the USBNET_MII_DECL_DEFAULT() macro for
210  * sane default.  Pass a copy to usbnet_attach_ifp().  Not used
211  * after the usbnet_attach_ifp() function returns.
212  */
213 struct usbnet_mii {
214 	int			un_mii_flags;
215 	int			un_mii_capmask;
216 	int			un_mii_phyloc;
217 	int			un_mii_offset;
218 };
219 
220 #define USBNET_MII_DECL(name, capmask, loc, off, flags)	\
221 	struct usbnet_mii name = {			\
222 		.un_mii_capmask = capmask,		\
223 		.un_mii_phyloc = loc,			\
224 		.un_mii_offset = off,			\
225 		.un_mii_flags = flags,			\
226 	}
227 #define USBNET_MII_DECL_DEFAULT(name)				\
228 	USBNET_MII_DECL(name, 0xffffffff, MII_PHY_ANY, MII_OFFSET_ANY, 0)
229 
230 /*
231  * Generic USB ethernet structure.  Use this as ifp->if_softc and set as
232  * device_private() in attach unless already using struct usbnet here.
233  *
234  * Devices without MII should call usbnet_attach_ifp() with have_mii set
235  * to true, and should ensure that the un_statchg_cb callback sets the
236  * un_link member.  Devices without MII have this forced to true.
237  */
238 struct usbnet_private;
239 struct usbnet {
240 	/*
241 	 * This section should be filled in before calling
242 	 * usbnet_attach().
243 	 */
244 	void			*un_sc;			/* real softc */
245 	device_t		un_dev;
246 	struct usbd_interface	*un_iface;
247 	struct usbd_device	*un_udev;
248 	const struct usbnet_ops	*un_ops;
249 	struct usbnet_intr	*un_intr;
250 
251 	/* Inputs for rx/tx chain control. */
252 	unsigned		un_rx_bufsz;
253 	unsigned		un_tx_bufsz;
254 	unsigned		un_rx_list_cnt;
255 	unsigned		un_tx_list_cnt;
256 	int			un_rx_xfer_flags;
257 	int			un_tx_xfer_flags;
258 
259 	/*
260 	 * This section should be filled in before calling
261 	 * usbnet_attach_ifp().
262 	 *
263 	 * XXX This should be of type "uByte".  enum usbnet_ep
264 	 * is the index.  Fix this in a kernel version bump.
265 	 */
266 	enum usbnet_ep		un_ed[USBNET_ENDPT_MAX];
267 
268 	/* MII specific. Not used without MII. */
269 	int			un_phyno;
270 	/* Ethernet specific. All zeroes indicates non-Ethernet. */
271 	uint8_t			un_eaddr[ETHER_ADDR_LEN];
272 
273 	/*
274 	 * This section is for driver to use, not touched by usbnet.
275 	 */
276 	unsigned		un_flags;
277 
278 	/*
279 	 * This section is private to usbnet. Don't touch.
280 	 */
281 	struct usbnet_private	*un_pri;
282 };
283 
284 /* Various accessors. */
285 
286 void usbnet_set_link(struct usbnet *, bool);
287 void usbnet_set_dying(struct usbnet *, bool);
288 
289 struct ifnet *usbnet_ifp(struct usbnet *);
290 struct ethercom *usbnet_ec(struct usbnet *);
291 struct mii_data *usbnet_mii(struct usbnet *);
292 krndsource_t *usbnet_rndsrc(struct usbnet *);
293 void *usbnet_softc(struct usbnet *);
294 
295 bool usbnet_havelink(struct usbnet *);
296 bool usbnet_isdying(struct usbnet *);
297 
298 
299 /*
300  * Locking.  Note that the isowned() are implemented here so that
301  * empty-KASSERT() causes them to be elided for non-DIAG builds.
302  */
303 void	usbnet_lock_core(struct usbnet *);
304 void	usbnet_unlock_core(struct usbnet *);
305 kmutex_t *usbnet_mutex_core(struct usbnet *);
306 static __inline__ void
307 usbnet_isowned_core(struct usbnet *un)
308 {
309 	KASSERT(mutex_owned(usbnet_mutex_core(un)));
310 }
311 
312 void	usbnet_busy(struct usbnet *);
313 void	usbnet_unbusy(struct usbnet *);
314 
315 void	usbnet_lock_rx(struct usbnet *);
316 void	usbnet_unlock_rx(struct usbnet *);
317 kmutex_t *usbnet_mutex_rx(struct usbnet *);
318 static __inline__ void
319 usbnet_isowned_rx(struct usbnet *un)
320 {
321 	KASSERT(mutex_owned(usbnet_mutex_rx(un)));
322 }
323 
324 void	usbnet_lock_tx(struct usbnet *);
325 void	usbnet_unlock_tx(struct usbnet *);
326 kmutex_t *usbnet_mutex_tx(struct usbnet *);
327 static __inline__ void
328 usbnet_isowned_tx(struct usbnet *un)
329 {
330 	KASSERT(mutex_owned(usbnet_mutex_tx(un)));
331 }
332 
333 /*
334  * Endpoint / rx/tx chain management:
335  *
336  * usbnet_attach() initialises usbnet and allocates rx and tx chains
337  * usbnet_init_rx_tx() open pipes, initialises the rx/tx chains for use
338  * usbnet_stop() stops pipes, cleans (not frees) rx/tx chains, locked
339  *               version assumes un_lock is held
340  * usbnet_detach() frees the rx/tx chains
341  *
342  * Setup un_ed[] with valid end points before calling usbnet_attach().
343  * Call usbnet_init_rx_tx() to initialise pipes, which will be open
344  * upon success.
345  */
346 int	usbnet_init_rx_tx(struct usbnet * const);
347 
348 /* MII. */
349 int	usbnet_mii_readreg(device_t, int, int, uint16_t *);
350 int	usbnet_mii_writereg(device_t, int, int, uint16_t);
351 void	usbnet_mii_statchg(struct ifnet *);
352 
353 /* interrupt handling */
354 void	usbnet_enqueue(struct usbnet * const, uint8_t *, size_t, int,
355 		       uint32_t, int);
356 void	usbnet_input(struct usbnet * const, uint8_t *, size_t);
357 
358 /* autoconf */
359 void	usbnet_attach(struct usbnet *un, const char *);
360 void	usbnet_attach_ifp(struct usbnet *, unsigned, unsigned,
361 			  const struct usbnet_mii *);
362 int	usbnet_detach(device_t, int);
363 int	usbnet_activate(device_t, devact_t);
364 
365 /* stop backend */
366 void	usbnet_stop(struct usbnet *, struct ifnet *, int);
367 
368 /* module hook up */
369 
370 #ifdef _MODULE
371 #define USBNET_INIT(name)						\
372 	error = config_init_component(cfdriver_ioconf_##name,		\
373 	    cfattach_ioconf_##name, cfdata_ioconf_##name);
374 #define USBNET_FINI(name)						\
375 	error = config_fini_component(cfdriver_ioconf_##name,		\
376 	    cfattach_ioconf_##name, cfdata_ioconf_##name);
377 #else
378 #define USBNET_INIT(name)
379 #define USBNET_FINI(name)
380 #endif
381 
382 #define USBNET_MODULE(name)						\
383 									\
384 MODULE(MODULE_CLASS_DRIVER, if_##name, "usbnet");			\
385 									\
386 static int								\
387 if_##name##_modcmd(modcmd_t cmd, void *aux)				\
388 {									\
389 	int error = 0;							\
390 									\
391 	switch (cmd) {							\
392 	case MODULE_CMD_INIT:						\
393 		USBNET_INIT(name)					\
394 		return error;						\
395 	case MODULE_CMD_FINI:						\
396 		USBNET_FINI(name)					\
397 		return error;						\
398 	default:							\
399 		return ENOTTY;						\
400 	}								\
401 }
402 
403 #endif /* _DEV_USB_USBNET_H */
404