xref: /freebsd/sys/dev/usb/serial/umcs.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2010 Lev Serebryakov <lev@FreeBSD.org>.
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 AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, 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 /*
30  * This driver supports several multiport USB-to-RS232 serial adapters driven
31  * by MosChip mos7820 and mos7840, bridge chips.
32  * The adapters are sold under many different brand names.
33  *
34  * Datasheets are available at MosChip www site at
35  * http://www.moschip.com.  The datasheets don't contain full
36  * programming information for the chip.
37  *
38  * It is nornal to have only two enabled ports in devices, based on
39  * quad-port mos7840.
40  *
41  */
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
44 
45 #include <sys/stdint.h>
46 #include <sys/stddef.h>
47 #include <sys/param.h>
48 #include <sys/queue.h>
49 #include <sys/types.h>
50 #include <sys/systm.h>
51 #include <sys/kernel.h>
52 #include <sys/bus.h>
53 #include <sys/linker_set.h>
54 #include <sys/module.h>
55 #include <sys/lock.h>
56 #include <sys/mutex.h>
57 #include <sys/condvar.h>
58 #include <sys/sysctl.h>
59 #include <sys/sx.h>
60 #include <sys/unistd.h>
61 #include <sys/callout.h>
62 #include <sys/malloc.h>
63 #include <sys/priv.h>
64 
65 #include <dev/usb/usb.h>
66 #include <dev/usb/usbdi.h>
67 #include <dev/usb/usbdi_util.h>
68 #include <dev/usb/usb_cdc.h>
69 #include "usbdevs.h"
70 
71 #define	USB_DEBUG_VAR umcs_debug
72 #include <dev/usb/usb_debug.h>
73 #include <dev/usb/usb_process.h>
74 
75 #include <dev/usb/serial/usb_serial.h>
76 
77 #include <dev/usb/serial/umcs.h>
78 
79 #define	UMCS7840_MODVER	1
80 
81 #ifdef USB_DEBUG
82 static int umcs_debug = 0;
83 
84 static SYSCTL_NODE(_hw_usb, OID_AUTO, umcs, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
85     "USB umcs quadport serial adapter");
86 SYSCTL_INT(_hw_usb_umcs, OID_AUTO, debug, CTLFLAG_RWTUN, &umcs_debug, 0, "Debug level");
87 #endif					/* USB_DEBUG */
88 
89 /*
90  * Two-port devices (both with 7820 chip and 7840 chip configured as two-port)
91  * have ports 0 and 2, with ports 1 and 3 omitted.
92  * So,PHYSICAL port numbers (indexes) on two-port device will be 0 and 2.
93  * This driver trys to use physical numbers as much as possible.
94  */
95 
96 /*
97  * Indexed by PHYSICAL port number.
98  * Pack non-regular registers to array to easier if-less access.
99  */
100 struct umcs7840_port_registers {
101 	uint8_t	reg_sp;			/* SP register. */
102 	uint8_t	reg_control;		/* CONTROL register. */
103 	uint8_t	reg_dcr;		/* DCR0 register. DCR1 & DCR2 can be
104 					 * calculated */
105 };
106 
107 static const struct umcs7840_port_registers umcs7840_port_registers[UMCS7840_MAX_PORTS] = {
108 	{.reg_sp = MCS7840_DEV_REG_SP1,.reg_control = MCS7840_DEV_REG_CONTROL1,.reg_dcr = MCS7840_DEV_REG_DCR0_1},
109 	{.reg_sp = MCS7840_DEV_REG_SP2,.reg_control = MCS7840_DEV_REG_CONTROL2,.reg_dcr = MCS7840_DEV_REG_DCR0_2},
110 	{.reg_sp = MCS7840_DEV_REG_SP3,.reg_control = MCS7840_DEV_REG_CONTROL3,.reg_dcr = MCS7840_DEV_REG_DCR0_3},
111 	{.reg_sp = MCS7840_DEV_REG_SP4,.reg_control = MCS7840_DEV_REG_CONTROL4,.reg_dcr = MCS7840_DEV_REG_DCR0_4},
112 };
113 
114 enum {
115 	UMCS7840_BULK_RD_EP,
116 	UMCS7840_BULK_WR_EP,
117 	UMCS7840_N_TRANSFERS
118 };
119 
120 struct umcs7840_softc_oneport {
121 	struct usb_xfer *sc_xfer[UMCS7840_N_TRANSFERS];	/* Control structures
122 							 * for two transfers */
123 
124 	uint8_t	sc_lcr;			/* local line control register */
125 	uint8_t	sc_mcr;			/* local modem control register */
126 };
127 
128 struct umcs7840_softc {
129 	struct ucom_super_softc sc_super_ucom;
130 	struct ucom_softc sc_ucom[UMCS7840_MAX_PORTS];	/* Need to be continuous
131 							 * array, so indexed by
132 							 * LOGICAL port
133 							 * (subunit) number */
134 
135 	struct usb_xfer *sc_intr_xfer;	/* Interrupt endpoint */
136 
137 	device_t sc_dev;		/* Device for error prints */
138 	struct usb_device *sc_udev;	/* USB Device for all operations */
139 	struct mtx sc_mtx;		/* ucom requires this */
140 
141 	uint8_t	sc_driver_done;		/* Flag when enumeration is finished */
142 
143 	uint8_t	sc_numports;		/* Number of ports (subunits) */
144 	struct umcs7840_softc_oneport sc_ports[UMCS7840_MAX_PORTS];	/* Indexed by PHYSICAL
145 									 * port number. */
146 };
147 
148 /* prototypes */
149 static usb_error_t umcs7840_get_reg_sync(struct umcs7840_softc *, uint8_t, uint8_t *);
150 static usb_error_t umcs7840_set_reg_sync(struct umcs7840_softc *, uint8_t, uint8_t);
151 static usb_error_t umcs7840_get_UART_reg_sync(struct umcs7840_softc *, uint8_t, uint8_t, uint8_t *);
152 static usb_error_t umcs7840_set_UART_reg_sync(struct umcs7840_softc *, uint8_t, uint8_t, uint8_t);
153 
154 static usb_error_t umcs7840_set_baudrate(struct umcs7840_softc *, uint8_t, uint32_t);
155 static usb_error_t umcs7840_calc_baudrate(uint32_t rate, uint16_t *, uint8_t *);
156 
157 static void	umcs7840_free(struct ucom_softc *);
158 static void umcs7840_cfg_get_status(struct ucom_softc *, uint8_t *, uint8_t *);
159 static void umcs7840_cfg_set_dtr(struct ucom_softc *, uint8_t);
160 static void umcs7840_cfg_set_rts(struct ucom_softc *, uint8_t);
161 static void umcs7840_cfg_set_break(struct ucom_softc *, uint8_t);
162 static void umcs7840_cfg_param(struct ucom_softc *, struct termios *);
163 static void umcs7840_cfg_open(struct ucom_softc *);
164 static void umcs7840_cfg_close(struct ucom_softc *);
165 
166 static int umcs7840_pre_param(struct ucom_softc *, struct termios *);
167 
168 static void umcs7840_start_read(struct ucom_softc *);
169 static void umcs7840_stop_read(struct ucom_softc *);
170 
171 static void umcs7840_start_write(struct ucom_softc *);
172 static void umcs7840_stop_write(struct ucom_softc *);
173 
174 static void umcs7840_poll(struct ucom_softc *ucom);
175 
176 static device_probe_t umcs7840_probe;
177 static device_attach_t umcs7840_attach;
178 static device_detach_t umcs7840_detach;
179 static void umcs7840_free_softc(struct umcs7840_softc *);
180 
181 static usb_callback_t umcs7840_intr_callback;
182 static usb_callback_t umcs7840_read_callback1;
183 static usb_callback_t umcs7840_read_callback2;
184 static usb_callback_t umcs7840_read_callback3;
185 static usb_callback_t umcs7840_read_callback4;
186 static usb_callback_t umcs7840_write_callback1;
187 static usb_callback_t umcs7840_write_callback2;
188 static usb_callback_t umcs7840_write_callback3;
189 static usb_callback_t umcs7840_write_callback4;
190 
191 static void umcs7840_read_callbackN(struct usb_xfer *, usb_error_t, uint8_t);
192 static void umcs7840_write_callbackN(struct usb_xfer *, usb_error_t, uint8_t);
193 
194 /* Indexed by LOGICAL port number (subunit), so two-port device uses 0 & 1 */
195 static usb_callback_t *umcs7840_rw_callbacks[UMCS7840_MAX_PORTS][UMCS7840_N_TRANSFERS] = {
196 	{&umcs7840_read_callback1, &umcs7840_write_callback1},
197 	{&umcs7840_read_callback2, &umcs7840_write_callback2},
198 	{&umcs7840_read_callback3, &umcs7840_write_callback3},
199 	{&umcs7840_read_callback4, &umcs7840_write_callback4},
200 };
201 
202 static const struct usb_config umcs7840_bulk_config_data[UMCS7840_N_TRANSFERS] = {
203 	[UMCS7840_BULK_RD_EP] = {
204 		.type = UE_BULK,
205 		.endpoint = 0x01,
206 		.direction = UE_DIR_IN,
207 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
208 		.bufsize = 0,		/* use wMaxPacketSize */
209 		.callback = &umcs7840_read_callback1,
210 		.if_index = 0,
211 	},
212 
213 	[UMCS7840_BULK_WR_EP] = {
214 		.type = UE_BULK,
215 		.endpoint = 0x02,
216 		.direction = UE_DIR_OUT,
217 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
218 		.bufsize = 0,		/* use wMaxPacketSize */
219 		.callback = &umcs7840_write_callback1,
220 		.if_index = 0,
221 	},
222 };
223 
224 static const struct usb_config umcs7840_intr_config_data[1] = {
225 	[0] = {
226 		.type = UE_INTERRUPT,
227 		.endpoint = 0x09,
228 		.direction = UE_DIR_IN,
229 		.flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
230 		.bufsize = 0,		/* use wMaxPacketSize */
231 		.callback = &umcs7840_intr_callback,
232 		.if_index = 0,
233 	},
234 };
235 
236 static struct ucom_callback umcs7840_callback = {
237 	.ucom_cfg_get_status = &umcs7840_cfg_get_status,
238 
239 	.ucom_cfg_set_dtr = &umcs7840_cfg_set_dtr,
240 	.ucom_cfg_set_rts = &umcs7840_cfg_set_rts,
241 	.ucom_cfg_set_break = &umcs7840_cfg_set_break,
242 
243 	.ucom_cfg_param = &umcs7840_cfg_param,
244 	.ucom_cfg_open = &umcs7840_cfg_open,
245 	.ucom_cfg_close = &umcs7840_cfg_close,
246 
247 	.ucom_pre_param = &umcs7840_pre_param,
248 
249 	.ucom_start_read = &umcs7840_start_read,
250 	.ucom_stop_read = &umcs7840_stop_read,
251 
252 	.ucom_start_write = &umcs7840_start_write,
253 	.ucom_stop_write = &umcs7840_stop_write,
254 
255 	.ucom_poll = &umcs7840_poll,
256 	.ucom_free = &umcs7840_free,
257 };
258 
259 static const STRUCT_USB_HOST_ID umcs7840_devs[] = {
260 	{USB_VPI(USB_VENDOR_MOSCHIP, USB_PRODUCT_MOSCHIP_MCS7820, 0)},
261 	{USB_VPI(USB_VENDOR_MOSCHIP, USB_PRODUCT_MOSCHIP_MCS7840, 0)},
262 };
263 
264 static device_method_t umcs7840_methods[] = {
265 	DEVMETHOD(device_probe, umcs7840_probe),
266 	DEVMETHOD(device_attach, umcs7840_attach),
267 	DEVMETHOD(device_detach, umcs7840_detach),
268 	DEVMETHOD_END
269 };
270 
271 static driver_t umcs7840_driver = {
272 	.name = "umcs7840",
273 	.methods = umcs7840_methods,
274 	.size = sizeof(struct umcs7840_softc),
275 };
276 
277 DRIVER_MODULE(umcs7840, uhub, umcs7840_driver, 0, 0);
278 MODULE_DEPEND(umcs7840, ucom, 1, 1, 1);
279 MODULE_DEPEND(umcs7840, usb, 1, 1, 1);
280 MODULE_VERSION(umcs7840, UMCS7840_MODVER);
281 USB_PNP_HOST_INFO(umcs7840_devs);
282 
283 static int
284 umcs7840_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 
297 static int
298 umcs7840_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 
397 detach:
398 	umcs7840_detach(dev);
399 	return (ENXIO);
400 }
401 
402 static int
403 umcs7840_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 
421 UCOM_UNLOAD_DRAIN(umcs7840);
422 
423 static void
424 umcs7840_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 
432 static void
433 umcs7840_free(struct ucom_softc *ucom)
434 {
435 	umcs7840_free_softc(ucom->sc_parent);
436 }
437 
438 static void
439 umcs7840_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_IE;
501 	if (ucom->sc_tty == NULL || (ucom->sc_tty->t_termios.c_cflag & CNO_RTSDTR) == 0)
502 		sc->sc_ports[pn].sc_mcr |= MCS7840_UART_MCR_DTR | MCS7840_UART_MCR_RTS;
503 	if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, sc->sc_ports[pn].sc_mcr))
504 		return;
505 
506 	/* Clearing Bulkin and Bulkout FIFO */
507 	if (umcs7840_get_reg_sync(sc, umcs7840_port_registers[pn].reg_sp, &data))
508 		return;
509 	data |= MCS7840_DEV_SPx_RESET_OUT_FIFO | MCS7840_DEV_SPx_RESET_IN_FIFO;
510 	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_sp, data))
511 		return;
512 	data &= ~(MCS7840_DEV_SPx_RESET_OUT_FIFO | MCS7840_DEV_SPx_RESET_IN_FIFO);
513 	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_sp, data))
514 		return;
515 
516 	/* Set speed 9600 */
517 	if (umcs7840_set_baudrate(sc, pn, 9600))
518 		return;
519 
520 	/* Finally enable all interrupts -- documented */
521 	/*
522 	 * Copied from vendor driver, I don't know why we should read LCR
523 	 * here
524 	 */
525 	if (umcs7840_get_UART_reg_sync(sc, pn, MCS7840_UART_REG_LCR, &sc->sc_ports[pn].sc_lcr))
526 		return;
527 	if (umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_IER,
528 	    MCS7840_UART_IER_RXSTAT | MCS7840_UART_IER_MODEM))
529 		return;
530 
531 	/* Enable RX */
532 	if (umcs7840_get_reg_sync(sc, umcs7840_port_registers[pn].reg_control, &data))
533 		return;
534 	data &= ~MCS7840_DEV_CONTROLx_RX_DISABLE;
535 	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_control, data))
536 		return;
537 
538 	DPRINTF("Port %d has been opened\n", pn);
539 }
540 
541 static void
542 umcs7840_cfg_close(struct ucom_softc *ucom)
543 {
544 	struct umcs7840_softc *sc = ucom->sc_parent;
545 	uint16_t pn = ucom->sc_portno;
546 	uint8_t data;
547 
548 	umcs7840_stop_read(ucom);
549 	umcs7840_stop_write(ucom);
550 
551 	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, 0);
552 	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_IER, 0);
553 
554 	/* Disable RX */
555 	if (umcs7840_get_reg_sync(sc, umcs7840_port_registers[pn].reg_control, &data))
556 		return;
557 	data |= MCS7840_DEV_CONTROLx_RX_DISABLE;
558 	if (umcs7840_set_reg_sync(sc, umcs7840_port_registers[pn].reg_control, data))
559 		return;
560 	DPRINTF("Port %d has been closed\n", pn);
561 }
562 
563 static void
564 umcs7840_cfg_set_dtr(struct ucom_softc *ucom, uint8_t onoff)
565 {
566 	struct umcs7840_softc *sc = ucom->sc_parent;
567 	uint8_t pn = ucom->sc_portno;
568 
569 	if (onoff)
570 		sc->sc_ports[pn].sc_mcr |= MCS7840_UART_MCR_DTR;
571 	else
572 		sc->sc_ports[pn].sc_mcr &= ~MCS7840_UART_MCR_DTR;
573 
574 	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, sc->sc_ports[pn].sc_mcr);
575 	DPRINTF("Port %d DTR set to: %s\n", pn, onoff ? "on" : "off");
576 }
577 
578 static void
579 umcs7840_cfg_set_rts(struct ucom_softc *ucom, uint8_t onoff)
580 {
581 	struct umcs7840_softc *sc = ucom->sc_parent;
582 	uint8_t pn = ucom->sc_portno;
583 
584 	if (onoff)
585 		sc->sc_ports[pn].sc_mcr |= MCS7840_UART_MCR_RTS;
586 	else
587 		sc->sc_ports[pn].sc_mcr &= ~MCS7840_UART_MCR_RTS;
588 
589 	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_MCR, sc->sc_ports[pn].sc_mcr);
590 	DPRINTF("Port %d RTS set to: %s\n", pn, onoff ? "on" : "off");
591 }
592 
593 static void
594 umcs7840_cfg_set_break(struct ucom_softc *ucom, uint8_t onoff)
595 {
596 	struct umcs7840_softc *sc = ucom->sc_parent;
597 	uint8_t pn = ucom->sc_portno;
598 
599 	if (onoff)
600 		sc->sc_ports[pn].sc_lcr |= MCS7840_UART_LCR_BREAK;
601 	else
602 		sc->sc_ports[pn].sc_lcr &= ~MCS7840_UART_LCR_BREAK;
603 
604 	umcs7840_set_UART_reg_sync(sc, pn, MCS7840_UART_REG_LCR, sc->sc_ports[pn].sc_lcr);
605 	DPRINTF("Port %d BREAK set to: %s\n", pn, onoff ? "on" : "off");
606 }
607 
608 static void
609 umcs7840_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 static int
684 umcs7840_pre_param(struct ucom_softc *ucom, struct termios *t)
685 {
686 	uint8_t clk;
687 	uint16_t divisor;
688 
689 	if (umcs7840_calc_baudrate(t->c_ospeed, &divisor, &clk) || !divisor)
690 		return (EINVAL);
691 	return (0);
692 }
693 
694 static void
695 umcs7840_start_read(struct ucom_softc *ucom)
696 {
697 	struct umcs7840_softc *sc = ucom->sc_parent;
698 	uint8_t pn = ucom->sc_portno;
699 
700 	/* Start interrupt transfer */
701 	usbd_transfer_start(sc->sc_intr_xfer);
702 
703 	/* Start read transfer */
704 	usbd_transfer_start(sc->sc_ports[pn].sc_xfer[UMCS7840_BULK_RD_EP]);
705 }
706 
707 static void
708 umcs7840_stop_read(struct ucom_softc *ucom)
709 {
710 	struct umcs7840_softc *sc = ucom->sc_parent;
711 	uint8_t pn = ucom->sc_portno;
712 
713 	/* Stop read transfer */
714 	usbd_transfer_stop(sc->sc_ports[pn].sc_xfer[UMCS7840_BULK_RD_EP]);
715 }
716 
717 static void
718 umcs7840_start_write(struct ucom_softc *ucom)
719 {
720 	struct umcs7840_softc *sc = ucom->sc_parent;
721 	uint8_t pn = ucom->sc_portno;
722 
723 	/* Start interrupt transfer */
724 	usbd_transfer_start(sc->sc_intr_xfer);
725 
726 	/* Start write transfer */
727 	usbd_transfer_start(sc->sc_ports[pn].sc_xfer[UMCS7840_BULK_WR_EP]);
728 }
729 
730 static void
731 umcs7840_stop_write(struct ucom_softc *ucom)
732 {
733 	struct umcs7840_softc *sc = ucom->sc_parent;
734 	uint8_t pn = ucom->sc_portno;
735 
736 	/* Stop write transfer */
737 	usbd_transfer_stop(sc->sc_ports[pn].sc_xfer[UMCS7840_BULK_WR_EP]);
738 }
739 
740 static void
741 umcs7840_cfg_get_status(struct ucom_softc *ucom, uint8_t *lsr, uint8_t *msr)
742 {
743 	struct umcs7840_softc *sc = ucom->sc_parent;
744 	uint8_t pn = ucom->sc_portno;
745 	uint8_t	hw_msr = 0;	/* local modem status register */
746 
747 	/*
748 	 * Read status registers.  MSR bits need translation from ns16550 to
749 	 * SER_* values.  LSR bits are ns16550 in hardware and ucom.
750 	 */
751 	umcs7840_get_UART_reg_sync(sc, pn, MCS7840_UART_REG_LSR, lsr);
752 	umcs7840_get_UART_reg_sync(sc, pn, MCS7840_UART_REG_MSR, &hw_msr);
753 
754 	if (hw_msr & MCS7840_UART_MSR_NEGCTS)
755 		*msr |= SER_CTS;
756 
757 	if (hw_msr & MCS7840_UART_MSR_NEGDCD)
758 		*msr |= SER_DCD;
759 
760 	if (hw_msr & MCS7840_UART_MSR_NEGRI)
761 		*msr |= SER_RI;
762 
763 	if (hw_msr & MCS7840_UART_MSR_NEGDSR)
764 		*msr |= SER_DSR;
765 
766 	DPRINTF("Port %d status: LSR=%02x MSR=%02x\n", ucom->sc_portno, *lsr, *msr);
767 }
768 
769 static void
770 umcs7840_intr_callback(struct usb_xfer *xfer, usb_error_t error)
771 {
772 	struct umcs7840_softc *sc = usbd_xfer_softc(xfer);
773 	struct usb_page_cache *pc;
774 	uint8_t buf[13];
775 	int actlen;
776 	int subunit;
777 
778 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
779 
780 	switch (USB_GET_STATE(xfer)) {
781 	case USB_ST_TRANSFERRED:
782 		if (actlen == 5 || actlen == 13) {
783 			pc = usbd_xfer_get_frame(xfer, 0);
784 			usbd_copy_out(pc, 0, buf, actlen);
785 			/* Check status of all ports */
786 			for (subunit = 0; subunit < sc->sc_numports; ++subunit) {
787 				uint8_t pn = sc->sc_ucom[subunit].sc_portno;
788 
789 				if (buf[pn] & MCS7840_UART_ISR_NOPENDING)
790 					continue;
791 				DPRINTF("Port %d has pending interrupt: %02x (FIFO: %02x)\n", pn, buf[pn] & MCS7840_UART_ISR_INTMASK, buf[pn] & (~MCS7840_UART_ISR_INTMASK));
792 				switch (buf[pn] & MCS7840_UART_ISR_INTMASK) {
793 				case MCS7840_UART_ISR_RXERR:
794 				case MCS7840_UART_ISR_RXHASDATA:
795 				case MCS7840_UART_ISR_RXTIMEOUT:
796 				case MCS7840_UART_ISR_MSCHANGE:
797 					ucom_status_change(&sc->sc_ucom[subunit]);
798 					break;
799 				default:
800 					/* Do nothing */
801 					break;
802 				}
803 			}
804 		} else
805 			device_printf(sc->sc_dev, "Invalid interrupt data length %d", actlen);
806 		/* FALLTHROUGH */
807 	case USB_ST_SETUP:
808 tr_setup:
809 		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
810 		usbd_transfer_submit(xfer);
811 		return;
812 
813 	default:			/* Error */
814 		if (error != USB_ERR_CANCELLED) {
815 			/* try to clear stall first */
816 			usbd_xfer_set_stall(xfer);
817 			goto tr_setup;
818 		}
819 		return;
820 	}
821 }
822 
823 static void
824 umcs7840_read_callback1(struct usb_xfer *xfer, usb_error_t error)
825 {
826 	umcs7840_read_callbackN(xfer, error, 0);
827 }
828 
829 static void
830 umcs7840_read_callback2(struct usb_xfer *xfer, usb_error_t error)
831 {
832 	umcs7840_read_callbackN(xfer, error, 1);
833 }
834 static void
835 umcs7840_read_callback3(struct usb_xfer *xfer, usb_error_t error)
836 {
837 	umcs7840_read_callbackN(xfer, error, 2);
838 }
839 
840 static void
841 umcs7840_read_callback4(struct usb_xfer *xfer, usb_error_t error)
842 {
843 	umcs7840_read_callbackN(xfer, error, 3);
844 }
845 
846 static void
847 umcs7840_read_callbackN(struct usb_xfer *xfer, usb_error_t error, uint8_t subunit)
848 {
849 	struct umcs7840_softc *sc = usbd_xfer_softc(xfer);
850 	struct ucom_softc *ucom = &sc->sc_ucom[subunit];
851 	struct usb_page_cache *pc;
852 	int actlen;
853 
854 	usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
855 
856 	DPRINTF("Port %d read, state = %d, data length = %d\n", ucom->sc_portno, USB_GET_STATE(xfer), actlen);
857 
858 	switch (USB_GET_STATE(xfer)) {
859 	case USB_ST_TRANSFERRED:
860 		pc = usbd_xfer_get_frame(xfer, 0);
861 		ucom_put_data(ucom, pc, 0, actlen);
862 		/* FALLTHROUGH */
863 	case USB_ST_SETUP:
864 tr_setup:
865 		usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
866 		usbd_transfer_submit(xfer);
867 		return;
868 
869 	default:			/* Error */
870 		if (error != USB_ERR_CANCELLED) {
871 			/* try to clear stall first */
872 			usbd_xfer_set_stall(xfer);
873 			goto tr_setup;
874 		}
875 		return;
876 	}
877 }
878 
879 static void
880 umcs7840_write_callback1(struct usb_xfer *xfer, usb_error_t error)
881 {
882 	umcs7840_write_callbackN(xfer, error, 0);
883 }
884 
885 static void
886 umcs7840_write_callback2(struct usb_xfer *xfer, usb_error_t error)
887 {
888 	umcs7840_write_callbackN(xfer, error, 1);
889 }
890 
891 static void
892 umcs7840_write_callback3(struct usb_xfer *xfer, usb_error_t error)
893 {
894 	umcs7840_write_callbackN(xfer, error, 2);
895 }
896 
897 static void
898 umcs7840_write_callback4(struct usb_xfer *xfer, usb_error_t error)
899 {
900 	umcs7840_write_callbackN(xfer, error, 3);
901 }
902 
903 static void
904 umcs7840_write_callbackN(struct usb_xfer *xfer, usb_error_t error, uint8_t subunit)
905 {
906 	struct umcs7840_softc *sc = usbd_xfer_softc(xfer);
907 	struct ucom_softc *ucom = &sc->sc_ucom[subunit];
908 	struct usb_page_cache *pc;
909 	uint32_t actlen;
910 
911 	DPRINTF("Port %d write, state = %d\n", ucom->sc_portno, USB_GET_STATE(xfer));
912 
913 	switch (USB_GET_STATE(xfer)) {
914 	case USB_ST_SETUP:
915 	case USB_ST_TRANSFERRED:
916 tr_setup:
917 		pc = usbd_xfer_get_frame(xfer, 0);
918 		if (ucom_get_data(ucom, pc, 0, usbd_xfer_max_len(xfer), &actlen)) {
919 			DPRINTF("Port %d write, has %d bytes\n", ucom->sc_portno, actlen);
920 			usbd_xfer_set_frame_len(xfer, 0, actlen);
921 			usbd_transfer_submit(xfer);
922 		}
923 		return;
924 
925 	default:			/* Error */
926 		if (error != USB_ERR_CANCELLED) {
927 			/* try to clear stall first */
928 			usbd_xfer_set_stall(xfer);
929 			goto tr_setup;
930 		}
931 		return;
932 	}
933 }
934 
935 static void
936 umcs7840_poll(struct ucom_softc *ucom)
937 {
938 	struct umcs7840_softc *sc = ucom->sc_parent;
939 
940 	DPRINTF("Port %d poll\n", ucom->sc_portno);
941 	usbd_transfer_poll(sc->sc_ports[ucom->sc_portno].sc_xfer, UMCS7840_N_TRANSFERS);
942 	usbd_transfer_poll(&sc->sc_intr_xfer, 1);
943 }
944 
945 static usb_error_t
946 umcs7840_get_reg_sync(struct umcs7840_softc *sc, uint8_t reg, uint8_t *data)
947 {
948 	struct usb_device_request req;
949 	usb_error_t err;
950 	uint16_t len;
951 
952 	req.bmRequestType = UT_READ_VENDOR_DEVICE;
953 	req.bRequest = MCS7840_RDREQ;
954 	USETW(req.wValue, 0);
955 	USETW(req.wIndex, reg);
956 	USETW(req.wLength, UMCS7840_READ_LENGTH);
957 
958 	err = usbd_do_request_proc(sc->sc_udev, &sc->sc_super_ucom.sc_tq, &req, (void *)data, 0, &len, UMCS7840_CTRL_TIMEOUT);
959 	if (err == USB_ERR_NORMAL_COMPLETION && len != 1) {
960 		device_printf(sc->sc_dev, "Reading register %d failed: invalid length %d\n", reg, len);
961 		return (USB_ERR_INVAL);
962 	} else if (err)
963 		device_printf(sc->sc_dev, "Reading register %d failed: %s\n", reg, usbd_errstr(err));
964 	return (err);
965 }
966 
967 static usb_error_t
968 umcs7840_set_reg_sync(struct umcs7840_softc *sc, uint8_t reg, uint8_t data)
969 {
970 	struct usb_device_request req;
971 	usb_error_t err;
972 
973 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
974 	req.bRequest = MCS7840_WRREQ;
975 	USETW(req.wValue, data);
976 	USETW(req.wIndex, reg);
977 	USETW(req.wLength, 0);
978 
979 	err = usbd_do_request_proc(sc->sc_udev, &sc->sc_super_ucom.sc_tq, &req, NULL, 0, NULL, UMCS7840_CTRL_TIMEOUT);
980 	if (err)
981 		device_printf(sc->sc_dev, "Writing register %d failed: %s\n", reg, usbd_errstr(err));
982 
983 	return (err);
984 }
985 
986 static usb_error_t
987 umcs7840_get_UART_reg_sync(struct umcs7840_softc *sc, uint8_t portno, uint8_t reg, uint8_t *data)
988 {
989 	struct usb_device_request req;
990 	uint16_t wVal;
991 	usb_error_t err;
992 	uint16_t len;
993 
994 	/* portno is port number */
995 	wVal = ((uint16_t)(portno + 1)) << 8;
996 
997 	req.bmRequestType = UT_READ_VENDOR_DEVICE;
998 	req.bRequest = MCS7840_RDREQ;
999 	USETW(req.wValue, wVal);
1000 	USETW(req.wIndex, reg);
1001 	USETW(req.wLength, UMCS7840_READ_LENGTH);
1002 
1003 	err = usbd_do_request_proc(sc->sc_udev, &sc->sc_super_ucom.sc_tq, &req, (void *)data, 0, &len, UMCS7840_CTRL_TIMEOUT);
1004 	if (err == USB_ERR_NORMAL_COMPLETION && len != 1) {
1005 		device_printf(sc->sc_dev, "Reading UART%d register %d failed: invalid length %d\n", portno, reg, len);
1006 		return (USB_ERR_INVAL);
1007 	} else if (err)
1008 		device_printf(sc->sc_dev, "Reading UART%d register %d failed: %s\n", portno, reg, usbd_errstr(err));
1009 	return (err);
1010 }
1011 
1012 static usb_error_t
1013 umcs7840_set_UART_reg_sync(struct umcs7840_softc *sc, uint8_t portno, uint8_t reg, uint8_t data)
1014 {
1015 	struct usb_device_request req;
1016 	usb_error_t err;
1017 	uint16_t wVal;
1018 
1019 	/* portno is port number */
1020 	wVal = ((uint16_t)(portno + 1)) << 8 | data;
1021 
1022 	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
1023 	req.bRequest = MCS7840_WRREQ;
1024 	USETW(req.wValue, wVal);
1025 	USETW(req.wIndex, reg);
1026 	USETW(req.wLength, 0);
1027 
1028 	err = usbd_do_request_proc(sc->sc_udev, &sc->sc_super_ucom.sc_tq, &req, NULL, 0, NULL, UMCS7840_CTRL_TIMEOUT);
1029 	if (err)
1030 		device_printf(sc->sc_dev, "Writing UART%d register %d failed: %s\n", portno, reg, usbd_errstr(err));
1031 	return (err);
1032 }
1033 
1034 static usb_error_t
1035 umcs7840_set_baudrate(struct umcs7840_softc *sc, uint8_t portno, uint32_t rate)
1036 {
1037 	usb_error_t err;
1038 	uint16_t divisor;
1039 	uint8_t clk;
1040 	uint8_t data;
1041 
1042 	if (umcs7840_calc_baudrate(rate, &divisor, &clk)) {
1043 		DPRINTF("Port %d bad speed: %d\n", portno, rate);
1044 		return (-1);
1045 	}
1046 	if (divisor == 0 || (clk & MCS7840_DEV_SPx_CLOCK_MASK) != clk) {
1047 		DPRINTF("Port %d bad speed calculation: %d\n", portno, rate);
1048 		return (-1);
1049 	}
1050 	DPRINTF("Port %d set speed: %d (%02x / %d)\n", portno, rate, clk, divisor);
1051 
1052 	/* Set clock source for standard BAUD frequences */
1053 	err = umcs7840_get_reg_sync(sc, umcs7840_port_registers[portno].reg_sp, &data);
1054 	if (err)
1055 		return (err);
1056 	data &= MCS7840_DEV_SPx_CLOCK_MASK;
1057 	data |= clk;
1058 	err = umcs7840_set_reg_sync(sc, umcs7840_port_registers[portno].reg_sp, data);
1059 	if (err)
1060 		return (err);
1061 
1062 	/* Set divider */
1063 	sc->sc_ports[portno].sc_lcr |= MCS7840_UART_LCR_DIVISORS;
1064 	err = umcs7840_set_UART_reg_sync(sc, portno, MCS7840_UART_REG_LCR, sc->sc_ports[portno].sc_lcr);
1065 	if (err)
1066 		return (err);
1067 
1068 	err = umcs7840_set_UART_reg_sync(sc, portno, MCS7840_UART_REG_DLL, (uint8_t)(divisor & 0xff));
1069 	if (err)
1070 		return (err);
1071 	err = umcs7840_set_UART_reg_sync(sc, portno, MCS7840_UART_REG_DLM, (uint8_t)((divisor >> 8) & 0xff));
1072 	if (err)
1073 		return (err);
1074 
1075 	/* Turn off access to DLL/DLM registers of UART */
1076 	sc->sc_ports[portno].sc_lcr &= ~MCS7840_UART_LCR_DIVISORS;
1077 	err = umcs7840_set_UART_reg_sync(sc, portno, MCS7840_UART_REG_LCR, sc->sc_ports[portno].sc_lcr);
1078 	if (err)
1079 		return (err);
1080 	return (0);
1081 }
1082 
1083 /* Maximum speeds for standard frequences, when PLL is not used */
1084 static const uint32_t umcs7840_baudrate_divisors[] = {0, 115200, 230400, 403200, 460800, 806400, 921600, 1572864, 3145728,};
1085 static const uint8_t umcs7840_baudrate_divisors_len = nitems(umcs7840_baudrate_divisors);
1086 
1087 static usb_error_t
1088 umcs7840_calc_baudrate(uint32_t rate, uint16_t *divisor, uint8_t *clk)
1089 {
1090 	uint8_t i = 0;
1091 
1092 	if (rate > umcs7840_baudrate_divisors[umcs7840_baudrate_divisors_len - 1])
1093 		return (-1);
1094 
1095 	for (i = 0; i < umcs7840_baudrate_divisors_len - 1 &&
1096 	    !(rate > umcs7840_baudrate_divisors[i] && rate <= umcs7840_baudrate_divisors[i + 1]); ++i);
1097 	if (rate == 0)
1098 		*divisor = 1;	/* XXX */
1099 	else
1100 		*divisor = umcs7840_baudrate_divisors[i + 1] / rate;
1101 	/* 0x00 .. 0x70 */
1102 	*clk = i << MCS7840_DEV_SPx_CLOCK_SHIFT;
1103 	return (0);
1104 }
1105