1/*-
2 * Copyright (c) 2010 Lev Serebryakov <lev@FreeBSD.org>.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27/*
28 * This driver supports several multiport USB-to-RS232 serial adapters driven
29 * by MosChip mos7820 and mos7840, bridge chips.
30 * The adapters are sold under many different brand names.
31 *
32 * Datasheets are available at MosChip www site at
33 * http://www.moschip.com.  The datasheets don't contain full
34 * programming information for the chip.
35 *
36 * It is nornal to have only two enabled ports in devices, based on
37 * quad-port mos7840.
38 *
39 */
40#include <sys/cdefs.h>
41__FBSDID("$FreeBSD: stable/11/sys/dev/usb/serial/umcs.c 314501 2017-03-01 18:23:30Z ian $");
42
43#include <sys/stdint.h>
44#include <sys/stddef.h>
45#include <sys/param.h>
46#include <sys/queue.h>
47#include <sys/types.h>
48#include <sys/systm.h>
49#include <sys/kernel.h>
50#include <sys/bus.h>
51#include <sys/linker_set.h>
52#include <sys/module.h>
53#include <sys/lock.h>
54#include <sys/mutex.h>
55#include <sys/condvar.h>
56#include <sys/sysctl.h>
57#include <sys/sx.h>
58#include <sys/unistd.h>
59#include <sys/callout.h>
60#include <sys/malloc.h>
61#include <sys/priv.h>
62
63#include <dev/usb/usb.h>
64#include <dev/usb/usbdi.h>
65#include <dev/usb/usbdi_util.h>
66#include <dev/usb/usb_cdc.h>
67#include "usbdevs.h"
68
69#define	USB_DEBUG_VAR umcs_debug
70#include <dev/usb/usb_debug.h>
71#include <dev/usb/usb_process.h>
72
73#include <dev/usb/serial/usb_serial.h>
74
75#include <dev/usb/serial/umcs.h>
76
77#define	UMCS7840_MODVER	1
78
79#ifdef USB_DEBUG
80static int umcs_debug = 0;
81
82static SYSCTL_NODE(_hw_usb, OID_AUTO, umcs, CTLFLAG_RW, 0, "USB umcs quadport serial adapter");
83SYSCTL_INT(_hw_usb_umcs, OID_AUTO, debug, CTLFLAG_RWTUN, &umcs_debug, 0, "Debug level");
84#endif					/* USB_DEBUG */
85
86
87/*
88 * Two-port devices (both with 7820 chip and 7840 chip configured as two-port)
89 * have ports 0 and 2, with ports 1 and 3 omitted.
90 * So,PHYSICAL port numbers (indexes) on two-port device will be 0 and 2.
91 * This driver trys to use physical numbers as much as possible.
92 */
93
94/*
95 * Indexed by PHYSICAL port number.
96 * Pack non-regular registers to array to easier if-less access.
97 */
98struct umcs7840_port_registers {
99	uint8_t	reg_sp;			/* SP register. */
100	uint8_t	reg_control;		/* CONTROL register. */
101	uint8_t	reg_dcr;		/* DCR0 register. DCR1 & DCR2 can be
102					 * calculated */
103};
104
105static const struct umcs7840_port_registers umcs7840_port_registers[UMCS7840_MAX_PORTS] = {
106	{.reg_sp = MCS7840_DEV_REG_SP1,.reg_control = MCS7840_DEV_REG_CONTROL1,.reg_dcr = MCS7840_DEV_REG_DCR0_1},
107	{.reg_sp = MCS7840_DEV_REG_SP2,.reg_control = MCS7840_DEV_REG_CONTROL2,.reg_dcr = MCS7840_DEV_REG_DCR0_2},
108	{.reg_sp = MCS7840_DEV_REG_SP3,.reg_control = MCS7840_DEV_REG_CONTROL3,.reg_dcr = MCS7840_DEV_REG_DCR0_3},
109	{.reg_sp = MCS7840_DEV_REG_SP4,.reg_control = MCS7840_DEV_REG_CONTROL4,.reg_dcr = MCS7840_DEV_REG_DCR0_4},
110};
111
112enum {
113	UMCS7840_BULK_RD_EP,
114	UMCS7840_BULK_WR_EP,
115	UMCS7840_N_TRANSFERS
116};
117
118struct umcs7840_softc_oneport {
119	struct usb_xfer *sc_xfer[UMCS7840_N_TRANSFERS];	/* Control structures
120							 * for two transfers */
121
122	uint8_t	sc_lcr;			/* local line control register */
123	uint8_t	sc_mcr;			/* local modem control register */
124};
125
126struct umcs7840_softc {
127	struct ucom_super_softc sc_super_ucom;
128	struct ucom_softc sc_ucom[UMCS7840_MAX_PORTS];	/* Need to be continuous
129							 * array, so indexed by
130							 * LOGICAL port
131							 * (subunit) number */
132
133	struct usb_xfer *sc_intr_xfer;	/* Interrupt endpoint */
134
135	device_t sc_dev;		/* Device for error prints */
136	struct usb_device *sc_udev;	/* USB Device for all operations */
137	struct mtx sc_mtx;		/* ucom requires this */
138
139	uint8_t	sc_driver_done;		/* Flag when enumeration is finished */
140
141	uint8_t	sc_numports;		/* Number of ports (subunits) */
142	struct umcs7840_softc_oneport sc_ports[UMCS7840_MAX_PORTS];	/* Indexed by PHYSICAL
143									 * port number. */
144};
145
146/* prototypes */
147static usb_error_t umcs7840_get_reg_sync(struct umcs7840_softc *, uint8_t, uint8_t *);
148static usb_error_t umcs7840_set_reg_sync(struct umcs7840_softc *, uint8_t, uint8_t);
149static usb_error_t umcs7840_get_UART_reg_sync(struct umcs7840_softc *, uint8_t, uint8_t, uint8_t *);
150static usb_error_t umcs7840_set_UART_reg_sync(struct umcs7840_softc *, uint8_t, uint8_t, uint8_t);
151
152static usb_error_t umcs7840_set_baudrate(struct umcs7840_softc *, uint8_t, uint32_t);
153static usb_error_t umcs7840_calc_baudrate(uint32_t rate, uint16_t *, uint8_t *);
154
155static void	umcs7840_free(struct ucom_softc *);
156static void umcs7840_cfg_get_status(struct ucom_softc *, uint8_t *, uint8_t *);
157static void umcs7840_cfg_set_dtr(struct ucom_softc *, uint8_t);
158static void umcs7840_cfg_set_rts(struct ucom_softc *, uint8_t);
159static void umcs7840_cfg_set_break(struct ucom_softc *, uint8_t);
160static void umcs7840_cfg_param(struct ucom_softc *, struct termios *);
161static void umcs7840_cfg_open(struct ucom_softc *);
162static void umcs7840_cfg_close(struct ucom_softc *);
163
164static int umcs7840_pre_param(struct ucom_softc *, struct termios *);
165
166static void umcs7840_start_read(struct ucom_softc *);
167static void umcs7840_stop_read(struct ucom_softc *);
168
169static void umcs7840_start_write(struct ucom_softc *);
170static void umcs7840_stop_write(struct ucom_softc *);
171
172static void umcs7840_poll(struct ucom_softc *ucom);
173
174static device_probe_t umcs7840_probe;
175static device_attach_t umcs7840_attach;
176static device_detach_t umcs7840_detach;
177static void umcs7840_free_softc(struct umcs7840_softc *);
178
179static usb_callback_t umcs7840_intr_callback;
180static usb_callback_t umcs7840_read_callback1;
181static usb_callback_t umcs7840_read_callback2;
182static usb_callback_t umcs7840_read_callback3;
183static usb_callback_t umcs7840_read_callback4;
184static usb_callback_t umcs7840_write_callback1;
185static usb_callback_t umcs7840_write_callback2;
186static usb_callback_t umcs7840_write_callback3;
187static usb_callback_t umcs7840_write_callback4;
188
189static void umcs7840_read_callbackN(struct usb_xfer *, usb_error_t, uint8_t);
190static void umcs7840_write_callbackN(struct usb_xfer *, usb_error_t, uint8_t);
191
192/* Indexed by LOGICAL port number (subunit), so two-port device uses 0 & 1 */
193static usb_callback_t *umcs7840_rw_callbacks[UMCS7840_MAX_PORTS][UMCS7840_N_TRANSFERS] = {
194	{&umcs7840_read_callback1, &umcs7840_write_callback1},
195	{&umcs7840_read_callback2, &umcs7840_write_callback2},
196	{&umcs7840_read_callback3, &umcs7840_write_callback3},
197	{&umcs7840_read_callback4, &umcs7840_write_callback4},
198};
199
200static const struct usb_config umcs7840_bulk_config_data[UMCS7840_N_TRANSFERS] = {
201	[UMCS7840_BULK_RD_EP] = {
202		.type = UE_BULK,
203		.endpoint = 0x01,
204		.direction = UE_DIR_IN,
205		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
206		.bufsize = 0,		/* use wMaxPacketSize */
207		.callback = &umcs7840_read_callback1,
208		.if_index = 0,
209	},
210
211	[UMCS7840_BULK_WR_EP] = {
212		.type = UE_BULK,
213		.endpoint = 0x02,
214		.direction = UE_DIR_OUT,
215		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
216		.bufsize = 0,		/* use wMaxPacketSize */
217		.callback = &umcs7840_write_callback1,
218		.if_index = 0,
219	},
220};
221
222static const struct usb_config umcs7840_intr_config_data[1] = {
223	[0] = {
224		.type = UE_INTERRUPT,
225		.endpoint = 0x09,
226		.direction = UE_DIR_IN,
227		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
228		.bufsize = 0,		/* use wMaxPacketSize */
229		.callback = &umcs7840_intr_callback,
230		.if_index = 0,
231	},
232};
233
234static struct ucom_callback umcs7840_callback = {
235	.ucom_cfg_get_status = &umcs7840_cfg_get_status,
236
237	.ucom_cfg_set_dtr = &umcs7840_cfg_set_dtr,
238	.ucom_cfg_set_rts = &umcs7840_cfg_set_rts,
239	.ucom_cfg_set_break = &umcs7840_cfg_set_break,
240
241	.ucom_cfg_param = &umcs7840_cfg_param,
242	.ucom_cfg_open = &umcs7840_cfg_open,
243	.ucom_cfg_close = &umcs7840_cfg_close,
244
245	.ucom_pre_param = &umcs7840_pre_param,
246
247	.ucom_start_read = &umcs7840_start_read,
248	.ucom_stop_read = &umcs7840_stop_read,
249
250	.ucom_start_write = &umcs7840_start_write,
251	.ucom_stop_write = &umcs7840_stop_write,
252
253	.ucom_poll = &umcs7840_poll,
254	.ucom_free = &umcs7840_free,
255};
256
257static const STRUCT_USB_HOST_ID umcs7840_devs[] = {
258	{USB_VPI(USB_VENDOR_MOSCHIP, USB_PRODUCT_MOSCHIP_MCS7820, 0)},
259	{USB_VPI(USB_VENDOR_MOSCHIP, USB_PRODUCT_MOSCHIP_MCS7840, 0)},
260};
261
262static device_method_t umcs7840_methods[] = {
263	DEVMETHOD(device_probe, umcs7840_probe),
264	DEVMETHOD(device_attach, umcs7840_attach),
265	DEVMETHOD(device_detach, umcs7840_detach),
266	DEVMETHOD_END
267};
268
269static devclass_t umcs7840_devclass;
270
271static driver_t umcs7840_driver = {
272	.name = "umcs7840",
273	.methods = umcs7840_methods,
274	.size = sizeof(struct umcs7840_softc),
275};
276
277DRIVER_MODULE(umcs7840, uhub, umcs7840_driver, umcs7840_devclass, 0, 0);
278MODULE_DEPEND(umcs7840, ucom, 1, 1, 1);
279MODULE_DEPEND(umcs7840, usb, 1, 1, 1);
280MODULE_VERSION(umcs7840, UMCS7840_MODVER);
281USB_PNP_HOST_INFO(umcs7840_devs);
282
283static int
284umcs7840_probe(device_t dev)
285{
286	struct usb_attach_arg *uaa = device_get_ivars(dev);
287
288	if (uaa->usb_mode != USB_MODE_HOST)
289		return (ENXIO);
290	if (uaa->info.bConfigIndex != MCS7840_CONFIG_INDEX)
291		return (ENXIO);
292	if (uaa->info.bIfaceIndex != MCS7840_IFACE_INDEX)
293		return (ENXIO);
294	return (usbd_lookup_id_by_uaa(umcs7840_devs, sizeof(umcs7840_devs), uaa));
295}
296
297static int
298umcs7840_attach(device_t dev)
299{
300	struct usb_config umcs7840_config_tmp[UMCS7840_N_TRANSFERS];
301	struct usb_attach_arg *uaa = device_get_ivars(dev);
302	struct umcs7840_softc *sc = device_get_softc(dev);
303
304	uint8_t iface_index = MCS7840_IFACE_INDEX;
305	int error;
306	int subunit;
307	int n;
308	uint8_t data;
309
310	for (n = 0; n < UMCS7840_N_TRANSFERS; ++n)
311		umcs7840_config_tmp[n] = umcs7840_bulk_config_data[n];
312
313	device_set_usb_desc(dev);
314	mtx_init(&sc->sc_mtx, "umcs7840", NULL, MTX_DEF);
315	ucom_ref(&sc->sc_super_ucom);
316
317	sc->sc_dev = dev;
318	sc->sc_udev = uaa->device;
319
320	/*
321	 * Get number of ports
322	 * Documentation (full datasheet) says, that number of ports is
323	 * set as MCS7840_DEV_MODE_SELECT24S bit in MODE R/Only
324	 * register. But vendor driver uses these undocumented
325	 * register & bit.
326	 *
327	 * Experiments show, that MODE register can have `0'
328	 * (4 ports) bit on 2-port device, so use vendor driver's way.
329	 *
330	 * Also, see notes in header file for these constants.
331	 */
332	umcs7840_get_reg_sync(sc, MCS7840_DEV_REG_GPIO, &data);
333	if (data & MCS7840_DEV_GPIO_4PORTS) {
334		sc->sc_numports = 4;
335		/* Store physical port numbers in sc_portno */
336		sc->sc_ucom[0].sc_portno = 0;
337		sc->sc_ucom[1].sc_portno = 1;
338		sc->sc_ucom[2].sc_portno = 2;
339		sc->sc_ucom[3].sc_portno = 3;
340	} else {
341		sc->sc_numports = 2;
342		/* Store physical port numbers in sc_portno */
343		sc->sc_ucom[0].sc_portno = 0;
344		sc->sc_ucom[1].sc_portno = 2;	/* '1' is skipped */
345	}
346	device_printf(dev, "Chip mcs%04x, found %d active ports\n", uaa->info.idProduct, sc->sc_numports);
347	if (!umcs7840_get_reg_sync(sc, MCS7840_DEV_REG_MODE, &data)) {
348		device_printf(dev, "On-die confguration: RST: active %s, HRD: %s, PLL: %s, POR: %s, Ports: %s, EEPROM write %s, IrDA is %savailable\n",
349		    (data & MCS7840_DEV_MODE_RESET) ? "low" : "high",
350		    (data & MCS7840_DEV_MODE_SER_PRSNT) ? "yes" : "no",
351		    (data & MCS7840_DEV_MODE_PLLBYPASS) ? "bypassed" : "avail",
352		    (data & MCS7840_DEV_MODE_PORBYPASS) ? "bypassed" : "avail",
353		    (data & MCS7840_DEV_MODE_SELECT24S) ? "2" : "4",
354		    (data & MCS7840_DEV_MODE_EEPROMWR) ? "enabled" : "disabled",
355		    (data & MCS7840_DEV_MODE_IRDA) ? "" : "not ");
356	}
357	/* Setup all transfers */
358	for (subunit = 0; subunit < sc->sc_numports; ++subunit) {
359		for (n = 0; n < UMCS7840_N_TRANSFERS; ++n) {
360			/* Set endpoint address */
361			umcs7840_config_tmp[n].endpoint = umcs7840_bulk_config_data[n].endpoint + 2 * sc->sc_ucom[subunit].sc_portno;
362			umcs7840_config_tmp[n].callback = umcs7840_rw_callbacks[subunit][n];
363		}
364		error = usbd_transfer_setup(uaa->device,
365		    &iface_index, sc->sc_ports[sc->sc_ucom[subunit].sc_portno].sc_xfer, umcs7840_config_tmp,
366		    UMCS7840_N_TRANSFERS, sc, &sc->sc_mtx);
367		if (error) {
368			device_printf(dev, "allocating USB transfers failed for subunit %d of %d\n",
369			    subunit + 1, sc->sc_numports);
370			goto detach;
371		}
372	}
373	error = usbd_transfer_setup(uaa->device,
374	    &iface_index, &sc->sc_intr_xfer, umcs7840_intr_config_data,
375	    1, sc, &sc->sc_mtx);
376	if (error) {
377		device_printf(dev, "allocating USB transfers failed for interrupt\n");
378		goto detach;
379	}
380	/* clear stall at first run */
381	mtx_lock(&sc->sc_mtx);
382	for (subunit = 0; subunit < sc->sc_numports; ++subunit) {
383		usbd_xfer_set_stall(sc->sc_ports[sc->sc_ucom[subunit].sc_portno].sc_xfer[UMCS7840_BULK_RD_EP]);
384		usbd_xfer_set_stall(sc->sc_ports[sc->sc_ucom[subunit].sc_portno].sc_xfer[UMCS7840_BULK_WR_EP]);
385	}
386	mtx_unlock(&sc->sc_mtx);
387
388	error = ucom_attach(&sc->sc_super_ucom, sc->sc_ucom, sc->sc_numports, sc,
389	    &umcs7840_callback, &sc->sc_mtx);
390	if (error)
391		goto detach;
392
393	ucom_set_pnpinfo_usb(&sc->sc_super_ucom, dev);
394
395	return (0);
396
397detach:
398	umcs7840_detach(dev);
399	return (ENXIO);
400}
401
402static int
403umcs7840_detach(device_t dev)
404{
405	struct umcs7840_softc *sc = device_get_softc(dev);
406	int subunit;
407
408	ucom_detach(&sc->sc_super_ucom, sc->sc_ucom);
409
410	for (subunit = 0; subunit < sc->sc_numports; ++subunit)
411		usbd_transfer_unsetup(sc->sc_ports[sc->sc_ucom[subunit].sc_portno].sc_xfer, UMCS7840_N_TRANSFERS);
412	usbd_transfer_unsetup(&sc->sc_intr_xfer, 1);
413
414	device_claim_softc(dev);
415
416	umcs7840_free_softc(sc);
417
418	return (0);
419}
420
421UCOM_UNLOAD_DRAIN(umcs7840);
422
423static void
424umcs7840_free_softc(struct umcs7840_softc *sc)
425{
426	if (ucom_unref(&sc->sc_super_ucom)) {
427		mtx_destroy(&sc->sc_mtx);
428		device_free_softc(sc);
429	}
430}
431
432static void
433umcs7840_free(struct ucom_softc *ucom)
434{
435	umcs7840_free_softc(ucom->sc_parent);
436}
437
438static void
439umcs7840_cfg_open(struct ucom_softc *ucom)
440{
441	struct umcs7840_softc *sc = ucom->sc_parent;
442	uint16_t pn = ucom->sc_portno;
443	uint8_t data;
444
445	/* If it very first open, finish global configuration */
446	if (!sc->sc_driver_done) {
447		/*
448		 * USB enumeration is finished, pass internal memory to FIFOs
449		 * If it is done in the end of "attach", kernel panics.
450		 */
451		if (umcs7840_get_reg_sync(sc, MCS7840_DEV_REG_CONTROL1, &data))
452			return;
453		data |= MCS7840_DEV_CONTROL1_DRIVER_DONE;
454		if (umcs7840_set_reg_sync(sc, MCS7840_DEV_REG_CONTROL1, data))
455			return;
456		sc->sc_driver_done = 1;
457	}
458	/* Toggle reset bit on-off */
459	if (umcs7840_get_reg_sync(sc, umcs7840_port_registers[pn].reg_sp, &data))
460		return;
461	data |= MCS7840_DEV_SPx_UART_RESET;
462	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_sp, data))
463		return;
464	data &= ~MCS7840_DEV_SPx_UART_RESET;
465	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_sp, data))
466		return;
467
468	/* Set RS-232 mode */
469	if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_SCRATCHPAD, MCS7840_UART_SCRATCHPAD_RS232))
470		return;
471
472	/* Disable RX on time of initialization */
473	if (umcs7840_get_reg_sync(sc, umcs7840_port_registers[pn].reg_control, &data))
474		return;
475	data |= MCS7840_DEV_CONTROLx_RX_DISABLE;
476	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_control, data))
477		return;
478
479	/* Disable all interrupts */
480	if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_IER, 0))
481		return;
482
483	/* Reset FIFO -- documented */
484	if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_FCR, 0))
485		return;
486	if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_FCR,
487	    MCS7840_UART_FCR_ENABLE | MCS7840_UART_FCR_FLUSHRHR |
488	    MCS7840_UART_FCR_FLUSHTHR | MCS7840_UART_FCR_RTL_1_14))
489		return;
490
491	/* Set 8 bit, no parity, 1 stop bit -- documented */
492	sc->sc_ports[pn].sc_lcr = MCS7840_UART_LCR_DATALEN8 | MCS7840_UART_LCR_STOPB1;
493	if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_LCR, sc->sc_ports[pn].sc_lcr))
494		return;
495
496	/*
497	 * Enable DTR/RTS on modem control, enable modem interrupts --
498	 * documented
499	 */
500	sc->sc_ports[pn].sc_mcr = MCS7840_UART_MCR_DTR | MCS7840_UART_MCR_RTS | MCS7840_UART_MCR_IE;
501	if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, sc->sc_ports[pn].sc_mcr))
502		return;
503
504	/* Clearing Bulkin and Bulkout FIFO */
505	if (umcs7840_get_reg_sync(sc, umcs7840_port_registers[pn].reg_sp, &data))
506		return;
507	data |= MCS7840_DEV_SPx_RESET_OUT_FIFO | MCS7840_DEV_SPx_RESET_IN_FIFO;
508	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_sp, data))
509		return;
510	data &= ~(MCS7840_DEV_SPx_RESET_OUT_FIFO | MCS7840_DEV_SPx_RESET_IN_FIFO);
511	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_sp, data))
512		return;
513
514	/* Set speed 9600 */
515	if (umcs7840_set_baudrate(sc, pn, 9600))
516		return;
517
518
519	/* Finally enable all interrupts -- documented */
520	/*
521	 * Copied from vendor driver, I don't know why we should read LCR
522	 * here
523	 */
524	if (umcs7840_get_UART_reg_sync(sc, pn, MCS7840_UART_REG_LCR, &sc->sc_ports[pn].sc_lcr))
525		return;
526	if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_IER,
527	    MCS7840_UART_IER_RXSTAT | MCS7840_UART_IER_MODEM))
528		return;
529
530	/* Enable RX */
531	if (umcs7840_get_reg_sync(sc, umcs7840_port_registers[pn].reg_control, &data))
532		return;
533	data &= ~MCS7840_DEV_CONTROLx_RX_DISABLE;
534	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_control, data))
535		return;
536
537	DPRINTF("Port %d has been opened\n", pn);
538}
539
540static void
541umcs7840_cfg_close(struct ucom_softc *ucom)
542{
543	struct umcs7840_softc *sc = ucom->sc_parent;
544	uint16_t pn = ucom->sc_portno;
545	uint8_t data;
546
547	umcs7840_stop_read(ucom);
548	umcs7840_stop_write(ucom);
549
550	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, 0);
551	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_IER, 0);
552
553	/* Disable RX */
554	if (umcs7840_get_reg_sync(sc, umcs7840_port_registers[pn].reg_control, &data))
555		return;
556	data |= MCS7840_DEV_CONTROLx_RX_DISABLE;
557	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_control, data))
558		return;
559	DPRINTF("Port %d has been closed\n", pn);
560}
561
562static void
563umcs7840_cfg_set_dtr(struct ucom_softc *ucom, uint8_t onoff)
564{
565	struct umcs7840_softc *sc = ucom->sc_parent;
566	uint8_t pn = ucom->sc_portno;
567
568	if (onoff)
569		sc->sc_ports[pn].sc_mcr |= MCS7840_UART_MCR_DTR;
570	else
571		sc->sc_ports[pn].sc_mcr &= ~MCS7840_UART_MCR_DTR;
572
573	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, sc->sc_ports[pn].sc_mcr);
574	DPRINTF("Port %d DTR set to: %s\n", pn, onoff ? "on" : "off");
575}
576
577static void
578umcs7840_cfg_set_rts(struct ucom_softc *ucom, uint8_t onoff)
579{
580	struct umcs7840_softc *sc = ucom->sc_parent;
581	uint8_t pn = ucom->sc_portno;
582
583	if (onoff)
584		sc->sc_ports[pn].sc_mcr |= MCS7840_UART_MCR_RTS;
585	else
586		sc->sc_ports[pn].sc_mcr &= ~MCS7840_UART_MCR_RTS;
587
588	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, sc->sc_ports[pn].sc_mcr);
589	DPRINTF("Port %d RTS set to: %s\n", pn, onoff ? "on" : "off");
590}
591
592static void
593umcs7840_cfg_set_break(struct ucom_softc *ucom, uint8_t onoff)
594{
595	struct umcs7840_softc *sc = ucom->sc_parent;
596	uint8_t pn = ucom->sc_portno;
597
598	if (onoff)
599		sc->sc_ports[pn].sc_lcr |= MCS7840_UART_LCR_BREAK;
600	else
601		sc->sc_ports[pn].sc_lcr &= ~MCS7840_UART_LCR_BREAK;
602
603	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_LCR, sc->sc_ports[pn].sc_lcr);
604	DPRINTF("Port %d BREAK set to: %s\n", pn, onoff ? "on" : "off");
605}
606
607
608static void
609umcs7840_cfg_param(struct ucom_softc *ucom, struct termios *t)
610{
611	struct umcs7840_softc *sc = ucom->sc_parent;
612	uint8_t pn = ucom->sc_portno;
613	uint8_t lcr = sc->sc_ports[pn].sc_lcr;
614	uint8_t mcr = sc->sc_ports[pn].sc_mcr;
615
616	DPRINTF("Port %d config:\n", pn);
617	if (t->c_cflag & CSTOPB) {
618		DPRINTF("  2 stop bits\n");
619		lcr |= MCS7840_UART_LCR_STOPB2;
620	} else {
621		lcr |= MCS7840_UART_LCR_STOPB1;
622		DPRINTF("  1 stop bit\n");
623	}
624
625	lcr &= ~MCS7840_UART_LCR_PARITYMASK;
626	if (t->c_cflag & PARENB) {
627		lcr |= MCS7840_UART_LCR_PARITYON;
628		if (t->c_cflag & PARODD) {
629			lcr = MCS7840_UART_LCR_PARITYODD;
630			DPRINTF("  parity on - odd\n");
631		} else {
632			lcr = MCS7840_UART_LCR_PARITYEVEN;
633			DPRINTF("  parity on - even\n");
634		}
635	} else {
636		lcr &= ~MCS7840_UART_LCR_PARITYON;
637		DPRINTF("  parity off\n");
638	}
639
640	lcr &= ~MCS7840_UART_LCR_DATALENMASK;
641	switch (t->c_cflag & CSIZE) {
642	case CS5:
643		lcr |= MCS7840_UART_LCR_DATALEN5;
644		DPRINTF("  5 bit\n");
645		break;
646	case CS6:
647		lcr |= MCS7840_UART_LCR_DATALEN6;
648		DPRINTF("  6 bit\n");
649		break;
650	case CS7:
651		lcr |= MCS7840_UART_LCR_DATALEN7;
652		DPRINTF("  7 bit\n");
653		break;
654	case CS8:
655		lcr |= MCS7840_UART_LCR_DATALEN8;
656		DPRINTF("  8 bit\n");
657		break;
658	}
659
660	if (t->c_cflag & CRTSCTS) {
661		mcr |= MCS7840_UART_MCR_CTSRTS;
662		DPRINTF("  CTS/RTS\n");
663	} else
664		mcr &= ~MCS7840_UART_MCR_CTSRTS;
665
666	if (t->c_cflag & (CDTR_IFLOW | CDSR_OFLOW)) {
667		mcr |= MCS7840_UART_MCR_DTRDSR;
668		DPRINTF("  DTR/DSR\n");
669	} else
670		mcr &= ~MCS7840_UART_MCR_DTRDSR;
671
672	sc->sc_ports[pn].sc_lcr = lcr;
673	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_LCR, sc->sc_ports[pn].sc_lcr);
674	DPRINTF("Port %d LCR=%02x\n", pn, sc->sc_ports[pn].sc_lcr);
675
676	sc->sc_ports[pn].sc_mcr = mcr;
677	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, sc->sc_ports[pn].sc_mcr);
678	DPRINTF("Port %d MCR=%02x\n", pn, sc->sc_ports[pn].sc_mcr);
679
680	umcs7840_set_baudrate(sc, pn, t->c_ospeed);
681}
682
683
684static int
685umcs7840_pre_param(struct ucom_softc *ucom, struct termios *t)
686{
687	uint8_t clk;
688	uint16_t divisor;
689
690	if (umcs7840_calc_baudrate(t->c_ospeed, &divisor, &clk) || !divisor)
691		return (EINVAL);
692	return (0);
693}
694
695static void
696umcs7840_start_read(struct ucom_softc *ucom)
697{
698	struct umcs7840_softc *sc = ucom->sc_parent;
699	uint8_t pn = ucom->sc_portno;
700
701	/* Start interrupt transfer */
702	usbd_transfer_start(sc->sc_intr_xfer);
703
704	/* Start read transfer */
705	usbd_transfer_start(sc->sc_ports[pn].sc_xfer[UMCS7840_BULK_RD_EP]);
706}
707
708static void
709umcs7840_stop_read(struct ucom_softc *ucom)
710{
711	struct umcs7840_softc *sc = ucom->sc_parent;
712	uint8_t pn = ucom->sc_portno;
713
714	/* Stop read transfer */
715	usbd_transfer_stop(sc->sc_ports[pn].sc_xfer[UMCS7840_BULK_RD_EP]);
716}
717
718static void
719umcs7840_start_write(struct ucom_softc *ucom)
720{
721	struct umcs7840_softc *sc = ucom->sc_parent;
722	uint8_t pn = ucom->sc_portno;
723
724	/* Start interrupt transfer */
725	usbd_transfer_start(sc->sc_intr_xfer);
726
727	/* Start write transfer */
728	usbd_transfer_start(sc->sc_ports[pn].sc_xfer[UMCS7840_BULK_WR_EP]);
729}
730
731static void
732umcs7840_stop_write(struct ucom_softc *ucom)
733{
734	struct umcs7840_softc *sc = ucom->sc_parent;
735	uint8_t pn = ucom->sc_portno;
736
737	/* Stop write transfer */
738	usbd_transfer_stop(sc->sc_ports[pn].sc_xfer[UMCS7840_BULK_WR_EP]);
739}
740
741static void
742umcs7840_cfg_get_status(struct ucom_softc *ucom, uint8_t *lsr, uint8_t *msr)
743{
744	struct umcs7840_softc *sc = ucom->sc_parent;
745	uint8_t pn = ucom->sc_portno;
746	uint8_t	hw_msr = 0;	/* local modem status register */
747
748	/*
749	 * Read status registers.  MSR bits need translation from ns16550 to
750	 * SER_* values.  LSR bits are ns16550 in hardware and ucom.
751	 */
752	umcs7840_get_UART_reg_sync(sc, pn, MCS7840_UART_REG_LSR, lsr);
753	umcs7840_get_UART_reg_sync(sc, pn, MCS7840_UART_REG_MSR, &hw_msr);
754
755	if (hw_msr & MCS7840_UART_MSR_NEGCTS)
756		*msr |= SER_CTS;
757
758	if (hw_msr & MCS7840_UART_MSR_NEGDCD)
759		*msr |= SER_DCD;
760
761	if (hw_msr & MCS7840_UART_MSR_NEGRI)
762		*msr |= SER_RI;
763
764	if (hw_msr & MCS7840_UART_MSR_NEGDSR)
765		*msr |= SER_DSR;
766
767	DPRINTF("Port %d status: LSR=%02x MSR=%02x\n", ucom->sc_portno, *lsr, *msr);
768}
769
770static void
771umcs7840_intr_callback(struct usb_xfer *xfer, usb_error_t error)
772{
773	struct umcs7840_softc *sc = usbd_xfer_softc(xfer);
774	struct usb_page_cache *pc;
775	uint8_t buf[13];
776	int actlen;
777	int subunit;
778
779	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
780
781	switch (USB_GET_STATE(xfer)) {
782	case USB_ST_TRANSFERRED:
783		if (actlen == 5 || actlen == 13) {
784			pc = usbd_xfer_get_frame(xfer, 0);
785			usbd_copy_out(pc, 0, buf, actlen);
786			/* Check status of all ports */
787			for (subunit = 0; subunit < sc->sc_numports; ++subunit) {
788				uint8_t pn = sc->sc_ucom[subunit].sc_portno;
789
790				if (buf[pn] & MCS7840_UART_ISR_NOPENDING)
791					continue;
792				DPRINTF("Port %d has pending interrupt: %02x (FIFO: %02x)\n", pn, buf[pn] & MCS7840_UART_ISR_INTMASK, buf[pn] & (~MCS7840_UART_ISR_INTMASK));
793				switch (buf[pn] & MCS7840_UART_ISR_INTMASK) {
794				case MCS7840_UART_ISR_RXERR:
795				case MCS7840_UART_ISR_RXHASDATA:
796				case MCS7840_UART_ISR_RXTIMEOUT:
797				case MCS7840_UART_ISR_MSCHANGE:
798					ucom_status_change(&sc->sc_ucom[subunit]);
799					break;
800				default:
801					/* Do nothing */
802					break;
803				}
804			}
805		} else
806			device_printf(sc->sc_dev, "Invalid interrupt data length %d", actlen);
807		/* FALLTHROUGH */
808	case USB_ST_SETUP:
809tr_setup:
810		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
811		usbd_transfer_submit(xfer);
812		return;
813
814	default:			/* Error */
815		if (error != USB_ERR_CANCELLED) {
816			/* try to clear stall first */
817			usbd_xfer_set_stall(xfer);
818			goto tr_setup;
819		}
820		return;
821	}
822}
823
824static void
825umcs7840_read_callback1(struct usb_xfer *xfer, usb_error_t error)
826{
827	umcs7840_read_callbackN(xfer, error, 0);
828}
829
830static void
831umcs7840_read_callback2(struct usb_xfer *xfer, usb_error_t error)
832{
833	umcs7840_read_callbackN(xfer, error, 1);
834}
835static void
836umcs7840_read_callback3(struct usb_xfer *xfer, usb_error_t error)
837{
838	umcs7840_read_callbackN(xfer, error, 2);
839}
840
841static void
842umcs7840_read_callback4(struct usb_xfer *xfer, usb_error_t error)
843{
844	umcs7840_read_callbackN(xfer, error, 3);
845}
846
847static void
848umcs7840_read_callbackN(struct usb_xfer *xfer, usb_error_t error, uint8_t subunit)
849{
850	struct umcs7840_softc *sc = usbd_xfer_softc(xfer);
851	struct ucom_softc *ucom = &sc->sc_ucom[subunit];
852	struct usb_page_cache *pc;
853	int actlen;
854
855	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
856
857	DPRINTF("Port %d read, state = %d, data length = %d\n", ucom->sc_portno, USB_GET_STATE(xfer), actlen);
858
859	switch (USB_GET_STATE(xfer)) {
860	case USB_ST_TRANSFERRED:
861		pc = usbd_xfer_get_frame(xfer, 0);
862		ucom_put_data(ucom, pc, 0, actlen);
863		/* FALLTHROUGH */
864	case USB_ST_SETUP:
865tr_setup:
866		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
867		usbd_transfer_submit(xfer);
868		return;
869
870	default:			/* Error */
871		if (error != USB_ERR_CANCELLED) {
872			/* try to clear stall first */
873			usbd_xfer_set_stall(xfer);
874			goto tr_setup;
875		}
876		return;
877	}
878}
879
880static void
881umcs7840_write_callback1(struct usb_xfer *xfer, usb_error_t error)
882{
883	umcs7840_write_callbackN(xfer, error, 0);
884}
885
886static void
887umcs7840_write_callback2(struct usb_xfer *xfer, usb_error_t error)
888{
889	umcs7840_write_callbackN(xfer, error, 1);
890}
891
892static void
893umcs7840_write_callback3(struct usb_xfer *xfer, usb_error_t error)
894{
895	umcs7840_write_callbackN(xfer, error, 2);
896}
897
898static void
899umcs7840_write_callback4(struct usb_xfer *xfer, usb_error_t error)
900{
901	umcs7840_write_callbackN(xfer, error, 3);
902}
903
904static void
905umcs7840_write_callbackN(struct usb_xfer *xfer, usb_error_t error, uint8_t subunit)
906{
907	struct umcs7840_softc *sc = usbd_xfer_softc(xfer);
908	struct ucom_softc *ucom = &sc->sc_ucom[subunit];
909	struct usb_page_cache *pc;
910	uint32_t actlen;
911
912	DPRINTF("Port %d write, state = %d\n", ucom->sc_portno, USB_GET_STATE(xfer));
913
914	switch (USB_GET_STATE(xfer)) {
915	case USB_ST_SETUP:
916	case USB_ST_TRANSFERRED:
917tr_setup:
918		pc = usbd_xfer_get_frame(xfer, 0);
919		if (ucom_get_data(ucom, pc, 0, usbd_xfer_max_len(xfer), &actlen)) {
920			DPRINTF("Port %d write, has %d bytes\n", ucom->sc_portno, actlen);
921			usbd_xfer_set_frame_len(xfer, 0, actlen);
922			usbd_transfer_submit(xfer);
923		}
924		return;
925
926	default:			/* Error */
927		if (error != USB_ERR_CANCELLED) {
928			/* try to clear stall first */
929			usbd_xfer_set_stall(xfer);
930			goto tr_setup;
931		}
932		return;
933	}
934}
935
936static void
937umcs7840_poll(struct ucom_softc *ucom)
938{
939	struct umcs7840_softc *sc = ucom->sc_parent;
940
941	DPRINTF("Port %d poll\n", ucom->sc_portno);
942	usbd_transfer_poll(sc->sc_ports[ucom->sc_portno].sc_xfer, UMCS7840_N_TRANSFERS);
943	usbd_transfer_poll(&sc->sc_intr_xfer, 1);
944}
945
946static usb_error_t
947umcs7840_get_reg_sync(struct umcs7840_softc *sc, uint8_t reg, uint8_t *data)
948{
949	struct usb_device_request req;
950	usb_error_t err;
951	uint16_t len;
952
953	req.bmRequestType = UT_READ_VENDOR_DEVICE;
954	req.bRequest = MCS7840_RDREQ;
955	USETW(req.wValue, 0);
956	USETW(req.wIndex, reg);
957	USETW(req.wLength, UMCS7840_READ_LENGTH);
958
959	err = usbd_do_request_proc(sc->sc_udev, &sc->sc_super_ucom.sc_tq, &req, (void *)data, 0, &len, UMCS7840_CTRL_TIMEOUT);
960	if (err == USB_ERR_NORMAL_COMPLETION && len != 1) {
961		device_printf(sc->sc_dev, "Reading register %d failed: invalid length %d\n", reg, len);
962		return (USB_ERR_INVAL);
963	} else if (err)
964		device_printf(sc->sc_dev, "Reading register %d failed: %s\n", reg, usbd_errstr(err));
965	return (err);
966}
967
968static usb_error_t
969umcs7840_set_reg_sync(struct umcs7840_softc *sc, uint8_t reg, uint8_t data)
970{
971	struct usb_device_request req;
972	usb_error_t err;
973
974	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
975	req.bRequest = MCS7840_WRREQ;
976	USETW(req.wValue, data);
977	USETW(req.wIndex, reg);
978	USETW(req.wLength, 0);
979
980	err = usbd_do_request_proc(sc->sc_udev, &sc->sc_super_ucom.sc_tq, &req, NULL, 0, NULL, UMCS7840_CTRL_TIMEOUT);
981	if (err)
982		device_printf(sc->sc_dev, "Writing register %d failed: %s\n", reg, usbd_errstr(err));
983
984	return (err);
985}
986
987static usb_error_t
988umcs7840_get_UART_reg_sync(struct umcs7840_softc *sc, uint8_t portno, uint8_t reg, uint8_t *data)
989{
990	struct usb_device_request req;
991	uint16_t wVal;
992	usb_error_t err;
993	uint16_t len;
994
995	/* portno is port number */
996	wVal = ((uint16_t)(portno + 1)) << 8;
997
998	req.bmRequestType = UT_READ_VENDOR_DEVICE;
999	req.bRequest = MCS7840_RDREQ;
1000	USETW(req.wValue, wVal);
1001	USETW(req.wIndex, reg);
1002	USETW(req.wLength, UMCS7840_READ_LENGTH);
1003
1004	err = usbd_do_request_proc(sc->sc_udev, &sc->sc_super_ucom.sc_tq, &req, (void *)data, 0, &len, UMCS7840_CTRL_TIMEOUT);
1005	if (err == USB_ERR_NORMAL_COMPLETION && len != 1) {
1006		device_printf(sc->sc_dev, "Reading UART%d register %d failed: invalid length %d\n", portno, reg, len);
1007		return (USB_ERR_INVAL);
1008	} else if (err)
1009		device_printf(sc->sc_dev, "Reading UART%d register %d failed: %s\n", portno, reg, usbd_errstr(err));
1010	return (err);
1011}
1012
1013static usb_error_t
1014umcs7840_set_UART_reg_sync(struct umcs7840_softc *sc, uint8_t portno, uint8_t reg, uint8_t data)
1015{
1016	struct usb_device_request req;
1017	usb_error_t err;
1018	uint16_t wVal;
1019
1020	/* portno is port number */
1021	wVal = ((uint16_t)(portno + 1)) << 8 | data;
1022
1023	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
1024	req.bRequest = MCS7840_WRREQ;
1025	USETW(req.wValue, wVal);
1026	USETW(req.wIndex, reg);
1027	USETW(req.wLength, 0);
1028
1029	err = usbd_do_request_proc(sc->sc_udev, &sc->sc_super_ucom.sc_tq, &req, NULL, 0, NULL, UMCS7840_CTRL_TIMEOUT);
1030	if (err)
1031		device_printf(sc->sc_dev, "Writing UART%d register %d failed: %s\n", portno, reg, usbd_errstr(err));
1032	return (err);
1033}
1034
1035static usb_error_t
1036umcs7840_set_baudrate(struct umcs7840_softc *sc, uint8_t portno, uint32_t rate)
1037{
1038	usb_error_t err;
1039	uint16_t divisor;
1040	uint8_t clk;
1041	uint8_t data;
1042
1043	if (umcs7840_calc_baudrate(rate, &divisor, &clk)) {
1044		DPRINTF("Port %d bad speed: %d\n", portno, rate);
1045		return (-1);
1046	}
1047	if (divisor == 0 || (clk & MCS7840_DEV_SPx_CLOCK_MASK) != clk) {
1048		DPRINTF("Port %d bad speed calculation: %d\n", portno, rate);
1049		return (-1);
1050	}
1051	DPRINTF("Port %d set speed: %d (%02x / %d)\n", portno, rate, clk, divisor);
1052
1053	/* Set clock source for standard BAUD frequences */
1054	err = umcs7840_get_reg_sync(sc, umcs7840_port_registers[portno].reg_sp, &data);
1055	if (err)
1056		return (err);
1057	data &= MCS7840_DEV_SPx_CLOCK_MASK;
1058	data |= clk;
1059	err = umcs7840_set_reg_sync(sc, umcs7840_port_registers[portno].reg_sp, data);
1060	if (err)
1061		return (err);
1062
1063	/* Set divider */
1064	sc->sc_ports[portno].sc_lcr |= MCS7840_UART_LCR_DIVISORS;
1065	err = umcs7840_set_UART_reg_sync(sc, portno, MCS7840_UART_REG_LCR, sc->sc_ports[portno].sc_lcr);
1066	if (err)
1067		return (err);
1068
1069	err = umcs7840_set_UART_reg_sync(sc, portno, MCS7840_UART_REG_DLL, (uint8_t)(divisor & 0xff));
1070	if (err)
1071		return (err);
1072	err = umcs7840_set_UART_reg_sync(sc, portno, MCS7840_UART_REG_DLM, (uint8_t)((divisor >> 8) & 0xff));
1073	if (err)
1074		return (err);
1075
1076	/* Turn off access to DLL/DLM registers of UART */
1077	sc->sc_ports[portno].sc_lcr &= ~MCS7840_UART_LCR_DIVISORS;
1078	err = umcs7840_set_UART_reg_sync(sc, portno, MCS7840_UART_REG_LCR, sc->sc_ports[portno].sc_lcr);
1079	if (err)
1080		return (err);
1081	return (0);
1082}
1083
1084/* Maximum speeds for standard frequences, when PLL is not used */
1085static const uint32_t umcs7840_baudrate_divisors[] = {0, 115200, 230400, 403200, 460800, 806400, 921600, 1572864, 3145728,};
1086static const uint8_t umcs7840_baudrate_divisors_len = nitems(umcs7840_baudrate_divisors);
1087
1088static usb_error_t
1089umcs7840_calc_baudrate(uint32_t rate, uint16_t *divisor, uint8_t *clk)
1090{
1091	uint8_t i = 0;
1092
1093	if (rate > umcs7840_baudrate_divisors[umcs7840_baudrate_divisors_len - 1])
1094		return (-1);
1095
1096	for (i = 0; i < umcs7840_baudrate_divisors_len - 1 &&
1097	    !(rate > umcs7840_baudrate_divisors[i] && rate <= umcs7840_baudrate_divisors[i + 1]); ++i);
1098	if (rate == 0)
1099		*divisor = 1;	/* XXX */
1100	else
1101		*divisor = umcs7840_baudrate_divisors[i + 1] / rate;
1102	/* 0x00 .. 0x70 */
1103	*clk = i << MCS7840_DEV_SPx_CLOCK_SHIFT;
1104	return (0);
1105}
1106