FreeBSD/Linux Kernel Cross Reference
sys/dev/usb/serial/uchcom.c

     /*      $NetBSD: uchcom.c,v 1.1 2007/09/03 17:57:37 tshiozak Exp $      */
     
     /*-
      * SPDX-License-Identifier: BSD-2-Clause-FreeBSD AND BSD-2-Clause-NetBSD
      *
      * Copyright (c) 2007, Takanori Watanabe
      * All rights reserved.
      *
      * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     *
     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     * SUCH DAMAGE.
     */
    
    /*
     * Copyright (c) 2007 The NetBSD Foundation, Inc.
     * All rights reserved.
     *
     * This code is derived from software contributed to The NetBSD Foundation
     * by Takuya SHIOZAKI (tshiozak@netbsd.org).
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     *
     * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     * POSSIBILITY OF SUCH DAMAGE.
     */
    
    #include <sys/cdefs.h>
    __FBSDID("$FreeBSD$");
    
    /*
     * Driver for WinChipHead CH341/340, the worst USB-serial chip in the
     * world.
     */
    
    #include <sys/stdint.h>
    #include <sys/stddef.h>
    #include <sys/param.h>
    #include <sys/queue.h>
    #include <sys/types.h>
    #include <sys/systm.h>
    #include <sys/kernel.h>
    #include <sys/bus.h>
    #include <sys/module.h>
    #include <sys/lock.h>
    #include <sys/mutex.h>
    #include <sys/condvar.h>
    #include <sys/sysctl.h>
    #include <sys/sx.h>
    #include <sys/unistd.h>
    #include <sys/callout.h>
    #include <sys/malloc.h>
    #include <sys/priv.h>
    
    #include <dev/usb/usb.h>
    #include <dev/usb/usbdi.h>
    #include <dev/usb/usbdi_util.h>
    #include "usbdevs.h"
    
    #define USB_DEBUG_VAR uchcom_debug
    #include <dev/usb/usb_debug.h>
    #include <dev/usb/usb_process.h>
    
    #include <dev/usb/serial/usb_serial.h>
    
    #ifdef USB_DEBUG
    static int uchcom_debug = 0;
   
   static SYSCTL_NODE(_hw_usb, OID_AUTO, uchcom, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
       "USB uchcom");
   SYSCTL_INT(_hw_usb_uchcom, OID_AUTO, debug, CTLFLAG_RWTUN,
       &uchcom_debug, 0, "uchcom debug level");
   #endif
   
   #define UCHCOM_IFACE_INDEX      0
   #define UCHCOM_CONFIG_INDEX     0
   
   #define UCHCOM_REV_CH340        0x0250
   #define UCHCOM_INPUT_BUF_SIZE   8
   
   #define UCHCOM_REQ_GET_VERSION  0x5F
   #define UCHCOM_REQ_READ_REG     0x95
   #define UCHCOM_REQ_WRITE_REG    0x9A
   #define UCHCOM_REQ_RESET        0xA1
   #define UCHCOM_REQ_SET_DTRRTS   0xA4
   
   #define UCHCOM_REG_STAT1        0x06
   #define UCHCOM_REG_STAT2        0x07
   #define UCHCOM_REG_BPS_PRE      0x12
   #define UCHCOM_REG_BPS_DIV      0x13
   #define UCHCOM_REG_BPS_MOD      0x14
   #define UCHCOM_REG_BPS_PAD      0x0F
   #define UCHCOM_REG_BREAK1       0x05
   #define UCHCOM_REG_LCR1         0x18
   #define UCHCOM_REG_LCR2         0x25
   
   #define UCHCOM_VER_20           0x20
   #define UCHCOM_VER_30           0x30
   
   #define UCHCOM_BASE_UNKNOWN     0
   #define UCHCOM_BPS_MOD_BASE     20000000
   #define UCHCOM_BPS_MOD_BASE_OFS 1100
   
   #define UCHCOM_DTR_MASK         0x20
   #define UCHCOM_RTS_MASK         0x40
   
   #define UCHCOM_BRK_MASK         0x01
   
   #define UCHCOM_LCR1_MASK        0xAF
   #define UCHCOM_LCR2_MASK        0x07
   #define UCHCOM_LCR1_RX          0x80
   #define UCHCOM_LCR1_TX          0x40
   #define UCHCOM_LCR1_PARENB      0x08
   #define UCHCOM_LCR1_CS8         0x03
   #define UCHCOM_LCR2_PAREVEN     0x07
   #define UCHCOM_LCR2_PARODD      0x06
   #define UCHCOM_LCR2_PARMARK     0x05
   #define UCHCOM_LCR2_PARSPACE    0x04
   
   #define UCHCOM_INTR_STAT1       0x02
   #define UCHCOM_INTR_STAT2       0x03
   #define UCHCOM_INTR_LEAST       4
   
   #define UCHCOM_BULK_BUF_SIZE 1024       /* bytes */
   
   enum {
           UCHCOM_BULK_DT_WR,
           UCHCOM_BULK_DT_RD,
           UCHCOM_INTR_DT_RD,
           UCHCOM_N_TRANSFER,
   };
   
   struct uchcom_softc {
           struct ucom_super_softc sc_super_ucom;
           struct ucom_softc sc_ucom;
   
           struct usb_xfer *sc_xfer[UCHCOM_N_TRANSFER];
           struct usb_device *sc_udev;
           struct mtx sc_mtx;
   
           uint8_t sc_dtr;                 /* local copy */
           uint8_t sc_rts;                 /* local copy */
           uint8_t sc_version;
           uint8_t sc_msr;
           uint8_t sc_lsr;                 /* local status register */
   };
   
   struct uchcom_divider {
           uint8_t dv_prescaler;
           uint8_t dv_div;
           uint8_t dv_mod;
   };
   
   struct uchcom_divider_record {
           uint32_t dvr_high;
           uint32_t dvr_low;
           uint32_t dvr_base_clock;
           struct uchcom_divider dvr_divider;
   };
   
   static const struct uchcom_divider_record dividers[] =
   {
           {307200, 307200, UCHCOM_BASE_UNKNOWN, {7, 0xD9, 0}},
           {921600, 921600, UCHCOM_BASE_UNKNOWN, {7, 0xF3, 0}},
           {2999999, 23530, 6000000, {3, 0, 0}},
           {23529, 2942, 750000, {2, 0, 0}},
           {2941, 368, 93750, {1, 0, 0}},
           {367, 1, 11719, {0, 0, 0}},
   };
   
   #define NUM_DIVIDERS    nitems(dividers)
   
   static const STRUCT_USB_HOST_ID uchcom_devs[] = {
           {USB_VPI(USB_VENDOR_WCH, USB_PRODUCT_WCH_CH341SER, 0)},
           {USB_VPI(USB_VENDOR_WCH2, USB_PRODUCT_WCH2_CH341SER, 0)},
           {USB_VPI(USB_VENDOR_WCH2, USB_PRODUCT_WCH2_CH341SER_2, 0)},
           {USB_VPI(USB_VENDOR_WCH2, USB_PRODUCT_WCH2_CH341SER_3, 0)},
   };
   
   /* protypes */
   
   static void     uchcom_free(struct ucom_softc *);
   static int      uchcom_pre_param(struct ucom_softc *, struct termios *);
   static void     uchcom_cfg_get_status(struct ucom_softc *, uint8_t *,
                       uint8_t *);
   static void     uchcom_cfg_open(struct ucom_softc *ucom);
   static void     uchcom_cfg_param(struct ucom_softc *, struct termios *);
   static void     uchcom_cfg_set_break(struct ucom_softc *, uint8_t);
   static void     uchcom_cfg_set_dtr(struct ucom_softc *, uint8_t);
   static void     uchcom_cfg_set_rts(struct ucom_softc *, uint8_t);
   static void     uchcom_start_read(struct ucom_softc *);
   static void     uchcom_start_write(struct ucom_softc *);
   static void     uchcom_stop_read(struct ucom_softc *);
   static void     uchcom_stop_write(struct ucom_softc *);
   static void     uchcom_update_version(struct uchcom_softc *);
   static void     uchcom_convert_status(struct uchcom_softc *, uint8_t);
   static void     uchcom_update_status(struct uchcom_softc *);
   static void     uchcom_set_dtr_rts(struct uchcom_softc *);
   static int      uchcom_calc_divider_settings(struct uchcom_divider *, uint32_t);
   static void     uchcom_set_baudrate(struct uchcom_softc *, uint32_t);
   static void     uchcom_poll(struct ucom_softc *ucom);
   
   static device_probe_t uchcom_probe;
   static device_attach_t uchcom_attach;
   static device_detach_t uchcom_detach;
   static void uchcom_free_softc(struct uchcom_softc *);
   
   static usb_callback_t uchcom_intr_callback;
   static usb_callback_t uchcom_write_callback;
   static usb_callback_t uchcom_read_callback;
   
   static const struct usb_config uchcom_config_data[UCHCOM_N_TRANSFER] = {
           [UCHCOM_BULK_DT_WR] = {
                   .type = UE_BULK,
                   .endpoint = UE_ADDR_ANY,
                   .direction = UE_DIR_OUT,
                   .bufsize = UCHCOM_BULK_BUF_SIZE,
                   .flags = {.pipe_bof = 1,.force_short_xfer = 1,},
                   .callback = &uchcom_write_callback,
           },
   
           [UCHCOM_BULK_DT_RD] = {
                   .type = UE_BULK,
                   .endpoint = UE_ADDR_ANY,
                   .direction = UE_DIR_IN,
                   .bufsize = UCHCOM_BULK_BUF_SIZE,
                   .flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
                   .callback = &uchcom_read_callback,
           },
   
           [UCHCOM_INTR_DT_RD] = {
                   .type = UE_INTERRUPT,
                   .endpoint = UE_ADDR_ANY,
                   .direction = UE_DIR_IN,
                   .flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
                   .bufsize = 0,   /* use wMaxPacketSize */
                   .callback = &uchcom_intr_callback,
           },
   };
   
   static struct ucom_callback uchcom_callback = {
           .ucom_cfg_get_status = &uchcom_cfg_get_status,
           .ucom_cfg_set_dtr = &uchcom_cfg_set_dtr,
           .ucom_cfg_set_rts = &uchcom_cfg_set_rts,
           .ucom_cfg_set_break = &uchcom_cfg_set_break,
           .ucom_cfg_open = &uchcom_cfg_open,
           .ucom_cfg_param = &uchcom_cfg_param,
           .ucom_pre_param = &uchcom_pre_param,
           .ucom_start_read = &uchcom_start_read,
           .ucom_stop_read = &uchcom_stop_read,
           .ucom_start_write = &uchcom_start_write,
           .ucom_stop_write = &uchcom_stop_write,
           .ucom_poll = &uchcom_poll,
           .ucom_free = &uchcom_free,
   };
   
   /* ----------------------------------------------------------------------
    * driver entry points
    */
   
   static int
   uchcom_probe(device_t dev)
   {
           struct usb_attach_arg *uaa = device_get_ivars(dev);
   
           DPRINTFN(11, "\n");
   
           if (uaa->usb_mode != USB_MODE_HOST) {
                   return (ENXIO);
           }
           if (uaa->info.bConfigIndex != UCHCOM_CONFIG_INDEX) {
                   return (ENXIO);
           }
           if (uaa->info.bIfaceIndex != UCHCOM_IFACE_INDEX) {
                   return (ENXIO);
           }
           return (usbd_lookup_id_by_uaa(uchcom_devs, sizeof(uchcom_devs), uaa));
   }
   
   static int
   uchcom_attach(device_t dev)
   {
           struct uchcom_softc *sc = device_get_softc(dev);
           struct usb_attach_arg *uaa = device_get_ivars(dev);
           int error;
           uint8_t iface_index;
   
           DPRINTFN(11, "\n");
   
           device_set_usb_desc(dev);
           mtx_init(&sc->sc_mtx, "uchcom", NULL, MTX_DEF);
           ucom_ref(&sc->sc_super_ucom);
   
           sc->sc_udev = uaa->device;
   
           switch (uaa->info.idProduct) {
           case USB_PRODUCT_WCH2_CH341SER:
                   device_printf(dev, "CH340 detected\n");
                   break;
           case USB_PRODUCT_WCH2_CH341SER_2:
           case USB_PRODUCT_WCH2_CH341SER_3:
                   device_printf(dev, "CH341 detected\n");
                   break;
           default:
                   device_printf(dev, "New CH340/CH341 product 0x%04x detected\n",
                       uaa->info.idProduct);
                   break;
           }
   
           iface_index = UCHCOM_IFACE_INDEX;
           error = usbd_transfer_setup(uaa->device,
               &iface_index, sc->sc_xfer, uchcom_config_data,
               UCHCOM_N_TRANSFER, sc, &sc->sc_mtx);
   
           if (error) {
                   DPRINTF("one or more missing USB endpoints, "
                       "error=%s\n", usbd_errstr(error));
                   goto detach;
           }
   
           /* clear stall at first run */
           mtx_lock(&sc->sc_mtx);
           usbd_xfer_set_stall(sc->sc_xfer[UCHCOM_BULK_DT_WR]);
           usbd_xfer_set_stall(sc->sc_xfer[UCHCOM_BULK_DT_RD]);
           mtx_unlock(&sc->sc_mtx);
   
           error = ucom_attach(&sc->sc_super_ucom, &sc->sc_ucom, 1, sc,
               &uchcom_callback, &sc->sc_mtx);
           if (error) {
                   goto detach;
           }
           ucom_set_pnpinfo_usb(&sc->sc_super_ucom, dev);
   
           return (0);
   
   detach:
           uchcom_detach(dev);
           return (ENXIO);
   }
   
   static int
   uchcom_detach(device_t dev)
   {
           struct uchcom_softc *sc = device_get_softc(dev);
   
           DPRINTFN(11, "\n");
   
           ucom_detach(&sc->sc_super_ucom, &sc->sc_ucom);
           usbd_transfer_unsetup(sc->sc_xfer, UCHCOM_N_TRANSFER);
   
           device_claim_softc(dev);
   
           uchcom_free_softc(sc);
   
           return (0);
   }
   
   UCOM_UNLOAD_DRAIN(uchcom);
   
   static void
   uchcom_free_softc(struct uchcom_softc *sc)
   {
           if (ucom_unref(&sc->sc_super_ucom)) {
                   mtx_destroy(&sc->sc_mtx);
                   device_free_softc(sc);
           }
   }
   
   static void
   uchcom_free(struct ucom_softc *ucom)
   {
           uchcom_free_softc(ucom->sc_parent);
   }
   
   /* ----------------------------------------------------------------------
    * low level i/o
    */
   
   static void
   uchcom_ctrl_write(struct uchcom_softc *sc, uint8_t reqno,
       uint16_t value, uint16_t index)
   {
           struct usb_device_request req;
   
           req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
           req.bRequest = reqno;
           USETW(req.wValue, value);
           USETW(req.wIndex, index);
           USETW(req.wLength, 0);
   
           DPRINTF("WR REQ 0x%02X VAL 0x%04X IDX 0x%04X\n",
               reqno, value, index);
           ucom_cfg_do_request(sc->sc_udev,
               &sc->sc_ucom, &req, NULL, 0, 1000);
   }
   
   static void
   uchcom_ctrl_read(struct uchcom_softc *sc, uint8_t reqno,
       uint16_t value, uint16_t index, void *buf, uint16_t buflen)
   {
           struct usb_device_request req;
   
           req.bmRequestType = UT_READ_VENDOR_DEVICE;
           req.bRequest = reqno;
           USETW(req.wValue, value);
           USETW(req.wIndex, index);
           USETW(req.wLength, buflen);
   
           DPRINTF("RD REQ 0x%02X VAL 0x%04X IDX 0x%04X LEN %d\n",
               reqno, value, index, buflen);
           ucom_cfg_do_request(sc->sc_udev,
               &sc->sc_ucom, &req, buf, USB_SHORT_XFER_OK, 1000);
   }
   
   static void
   uchcom_write_reg(struct uchcom_softc *sc,
       uint8_t reg1, uint8_t val1, uint8_t reg2, uint8_t val2)
   {
           DPRINTF("0x%02X<-0x%02X, 0x%02X<-0x%02X\n",
               (unsigned)reg1, (unsigned)val1,
               (unsigned)reg2, (unsigned)val2);
           uchcom_ctrl_write(
               sc, UCHCOM_REQ_WRITE_REG,
               reg1 | ((uint16_t)reg2 << 8), val1 | ((uint16_t)val2 << 8));
   }
   
   static void
   uchcom_read_reg(struct uchcom_softc *sc,
       uint8_t reg1, uint8_t *rval1, uint8_t reg2, uint8_t *rval2)
   {
           uint8_t buf[UCHCOM_INPUT_BUF_SIZE];
   
           uchcom_ctrl_read(
               sc, UCHCOM_REQ_READ_REG,
               reg1 | ((uint16_t)reg2 << 8), 0, buf, sizeof(buf));
   
           DPRINTF("0x%02X->0x%02X, 0x%02X->0x%02X\n",
               (unsigned)reg1, (unsigned)buf[0],
               (unsigned)reg2, (unsigned)buf[1]);
   
           if (rval1)
                   *rval1 = buf[0];
           if (rval2)
                   *rval2 = buf[1];
   }
   
   static void
   uchcom_get_version(struct uchcom_softc *sc, uint8_t *rver)
   {
           uint8_t buf[UCHCOM_INPUT_BUF_SIZE];
   
           uchcom_ctrl_read(sc, UCHCOM_REQ_GET_VERSION, 0, 0, buf, sizeof(buf));
   
           if (rver)
                   *rver = buf[0];
   }
   
   static void
   uchcom_get_status(struct uchcom_softc *sc, uint8_t *rval)
   {
           uchcom_read_reg(sc, UCHCOM_REG_STAT1, rval, UCHCOM_REG_STAT2, NULL);
   }
   
   static void
   uchcom_set_dtr_rts_10(struct uchcom_softc *sc, uint8_t val)
   {
           uchcom_write_reg(sc, UCHCOM_REG_STAT1, val, UCHCOM_REG_STAT1, val);
   }
   
   static void
   uchcom_set_dtr_rts_20(struct uchcom_softc *sc, uint8_t val)
   {
           uchcom_ctrl_write(sc, UCHCOM_REQ_SET_DTRRTS, val, 0);
   }
   
   /* ----------------------------------------------------------------------
    * middle layer
    */
   
   static void
   uchcom_update_version(struct uchcom_softc *sc)
   {
           uchcom_get_version(sc, &sc->sc_version);
           DPRINTF("Chip version: 0x%02x\n", sc->sc_version);
   }
   
   static void
   uchcom_convert_status(struct uchcom_softc *sc, uint8_t cur)
   {
           sc->sc_dtr = !(cur & UCHCOM_DTR_MASK);
           sc->sc_rts = !(cur & UCHCOM_RTS_MASK);
   
           cur = ~cur & 0x0F;
           sc->sc_msr = (cur << 4) | ((sc->sc_msr >> 4) ^ cur);
   }
   
   static void
   uchcom_update_status(struct uchcom_softc *sc)
   {
           uint8_t cur;
   
           uchcom_get_status(sc, &cur);
           uchcom_convert_status(sc, cur);
   }
   
   static void
   uchcom_set_dtr_rts(struct uchcom_softc *sc)
   {
           uint8_t val = 0;
   
           if (sc->sc_dtr)
                   val |= UCHCOM_DTR_MASK;
           if (sc->sc_rts)
                   val |= UCHCOM_RTS_MASK;
   
           if (sc->sc_version < UCHCOM_VER_20)
                   uchcom_set_dtr_rts_10(sc, ~val);
           else
                   uchcom_set_dtr_rts_20(sc, ~val);
   }
   
   static void
   uchcom_cfg_set_break(struct ucom_softc *ucom, uint8_t onoff)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
           uint8_t brk1;
           uint8_t brk2;
   
           uchcom_read_reg(sc, UCHCOM_REG_BREAK1, &brk1, UCHCOM_REG_LCR1, &brk2);
           if (onoff) {
                   /* on - clear bits */
                   brk1 &= ~UCHCOM_BRK_MASK;
                   brk2 &= ~UCHCOM_LCR1_TX;
           } else {
                   /* off - set bits */
                   brk1 |= UCHCOM_BRK_MASK;
                   brk2 |= UCHCOM_LCR1_TX;
           }
           uchcom_write_reg(sc, UCHCOM_REG_BREAK1, brk1, UCHCOM_REG_LCR1, brk2);
   }
   
   static int
   uchcom_calc_divider_settings(struct uchcom_divider *dp, uint32_t rate)
   {
           const struct uchcom_divider_record *rp;
           uint32_t div;
           uint32_t rem;
           uint32_t mod;
           uint8_t i;
   
           /* find record */
           for (i = 0; i != NUM_DIVIDERS; i++) {
                   if (dividers[i].dvr_high >= rate &&
                       dividers[i].dvr_low <= rate) {
                           rp = &dividers[i];
                           goto found;
                   }
           }
           return (-1);
   
   found:
           dp->dv_prescaler = rp->dvr_divider.dv_prescaler;
           if (rp->dvr_base_clock == UCHCOM_BASE_UNKNOWN)
                   dp->dv_div = rp->dvr_divider.dv_div;
           else {
                   div = rp->dvr_base_clock / rate;
                   rem = rp->dvr_base_clock % rate;
                   if (div == 0 || div >= 0xFF)
                           return (-1);
                   if ((rem << 1) >= rate)
                           div += 1;
                   dp->dv_div = (uint8_t)-div;
           }
   
           mod = (UCHCOM_BPS_MOD_BASE / rate) + UCHCOM_BPS_MOD_BASE_OFS;
           mod = mod + (mod / 2);
   
           dp->dv_mod = (mod + 0xFF) / 0x100;
   
           return (0);
   }
   
   static void
   uchcom_set_baudrate(struct uchcom_softc *sc, uint32_t rate)
   {
           struct uchcom_divider dv;
   
           if (uchcom_calc_divider_settings(&dv, rate))
                   return;
   
           /*
            * According to linux code we need to set bit 7 of UCHCOM_REG_BPS_PRE,
            * otherwise the chip will buffer data.
            */
           uchcom_write_reg(sc,
               UCHCOM_REG_BPS_PRE, dv.dv_prescaler | 0x80,
               UCHCOM_REG_BPS_DIV, dv.dv_div);
           uchcom_write_reg(sc,
               UCHCOM_REG_BPS_MOD, dv.dv_mod,
               UCHCOM_REG_BPS_PAD, 0);
   }
   
   /* ----------------------------------------------------------------------
    * methods for ucom
    */
   static void
   uchcom_cfg_get_status(struct ucom_softc *ucom, uint8_t *lsr, uint8_t *msr)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
   
           DPRINTF("\n");
   
           /* XXX Note: sc_lsr is always zero */
           *lsr = sc->sc_lsr;
           *msr = sc->sc_msr;
   }
   
   static void
   uchcom_cfg_set_dtr(struct ucom_softc *ucom, uint8_t onoff)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
   
           DPRINTF("onoff = %d\n", onoff);
   
           sc->sc_dtr = onoff;
           uchcom_set_dtr_rts(sc);
   }
   
   static void
   uchcom_cfg_set_rts(struct ucom_softc *ucom, uint8_t onoff)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
   
           DPRINTF("onoff = %d\n", onoff);
   
           sc->sc_rts = onoff;
           uchcom_set_dtr_rts(sc);
   }
   
   static void
   uchcom_cfg_open(struct ucom_softc *ucom)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
   
           DPRINTF("\n");
   
           uchcom_update_version(sc);
           uchcom_update_status(sc);
   }
   
   static int
   uchcom_pre_param(struct ucom_softc *ucom, struct termios *t)
   {
           struct uchcom_divider dv;
   
           switch (t->c_cflag & CSIZE) {
           case CS8:
                   break;
           default:
                   return (EIO);
           }
           if ((t->c_cflag & CSTOPB) != 0)
                   return (EIO);
           if ((t->c_cflag & PARENB) != 0)
                   return (EIO);
   
           if (uchcom_calc_divider_settings(&dv, t->c_ospeed)) {
                   return (EIO);
           }
           return (0);                     /* success */
   }
   
   static void
   uchcom_cfg_param(struct ucom_softc *ucom, struct termios *t)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
   
           uchcom_get_version(sc, NULL);
           uchcom_ctrl_write(sc, UCHCOM_REQ_RESET, 0, 0);
           uchcom_set_baudrate(sc, t->c_ospeed);
           if (sc->sc_version < UCHCOM_VER_30) {
                   uchcom_read_reg(sc, UCHCOM_REG_LCR1, NULL,
                       UCHCOM_REG_LCR2, NULL);
                   uchcom_write_reg(sc, UCHCOM_REG_LCR1, 0x50,
                       UCHCOM_REG_LCR2, 0x00);
           } else {
                   /*
                    * Set up line control:
                    * - enable transmit and receive
                    * - set 8n1 mode
                    * To do: support other sizes, parity, stop bits.
                    */
                   uchcom_write_reg(sc,
                       UCHCOM_REG_LCR1,
                       UCHCOM_LCR1_RX | UCHCOM_LCR1_TX | UCHCOM_LCR1_CS8,
                       UCHCOM_REG_LCR2, 0x00);
           }
           uchcom_update_status(sc);
           uchcom_ctrl_write(sc, UCHCOM_REQ_RESET, 0x501f, 0xd90a);
           uchcom_set_baudrate(sc, t->c_ospeed);
           uchcom_set_dtr_rts(sc);
           uchcom_update_status(sc);
   }
   
   static void
   uchcom_start_read(struct ucom_softc *ucom)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
   
           /* start interrupt endpoint */
           usbd_transfer_start(sc->sc_xfer[UCHCOM_INTR_DT_RD]);
   
           /* start read endpoint */
           usbd_transfer_start(sc->sc_xfer[UCHCOM_BULK_DT_RD]);
   }
   
   static void
   uchcom_stop_read(struct ucom_softc *ucom)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
   
           /* stop interrupt endpoint */
           usbd_transfer_stop(sc->sc_xfer[UCHCOM_INTR_DT_RD]);
   
           /* stop read endpoint */
           usbd_transfer_stop(sc->sc_xfer[UCHCOM_BULK_DT_RD]);
   }
   
   static void
   uchcom_start_write(struct ucom_softc *ucom)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
   
           usbd_transfer_start(sc->sc_xfer[UCHCOM_BULK_DT_WR]);
   }
   
   static void
   uchcom_stop_write(struct ucom_softc *ucom)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
   
           usbd_transfer_stop(sc->sc_xfer[UCHCOM_BULK_DT_WR]);
   }
   
   /* ----------------------------------------------------------------------
    * callback when the modem status is changed.
    */
   static void
   uchcom_intr_callback(struct usb_xfer *xfer, usb_error_t error)
   {
           struct uchcom_softc *sc = usbd_xfer_softc(xfer);
           struct usb_page_cache *pc;
           uint8_t buf[UCHCOM_INTR_LEAST];
           int actlen;
   
           usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
   
           switch (USB_GET_STATE(xfer)) {
           case USB_ST_TRANSFERRED:
   
                   DPRINTF("actlen = %u\n", actlen);
   
                   if (actlen >= UCHCOM_INTR_LEAST) {
                           pc = usbd_xfer_get_frame(xfer, 0);
                           usbd_copy_out(pc, 0, buf, UCHCOM_INTR_LEAST);
   
                           DPRINTF("data = 0x%02X 0x%02X 0x%02X 0x%02X\n",
                               (unsigned)buf[0], (unsigned)buf[1],
                               (unsigned)buf[2], (unsigned)buf[3]);
   
                           uchcom_convert_status(sc, buf[UCHCOM_INTR_STAT1]);
                           ucom_status_change(&sc->sc_ucom);
                   }
           case USB_ST_SETUP:
   tr_setup:
                   usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
                   usbd_transfer_submit(xfer);
                   break;
   
           default:                        /* Error */
                   if (error != USB_ERR_CANCELLED) {
                           /* try to clear stall first */
                           usbd_xfer_set_stall(xfer);
                           goto tr_setup;
                   }
                   break;
           }
   }
   
   static void
   uchcom_write_callback(struct usb_xfer *xfer, usb_error_t error)
   {
           struct uchcom_softc *sc = usbd_xfer_softc(xfer);
           struct usb_page_cache *pc;
           uint32_t actlen;
   
           switch (USB_GET_STATE(xfer)) {
           case USB_ST_SETUP:
           case USB_ST_TRANSFERRED:
   tr_setup:
                   pc = usbd_xfer_get_frame(xfer, 0);
                   if (ucom_get_data(&sc->sc_ucom, pc, 0,
                       usbd_xfer_max_len(xfer), &actlen)) {
                           DPRINTF("actlen = %d\n", actlen);
   
                           usbd_xfer_set_frame_len(xfer, 0, actlen);
                           usbd_transfer_submit(xfer);
                   }
                   break;
   
           default:                        /* Error */
                   if (error != USB_ERR_CANCELLED) {
                           /* try to clear stall first */
                           usbd_xfer_set_stall(xfer);
                           goto tr_setup;
                   }
                   break;
           }
   }
   
   static void
   uchcom_read_callback(struct usb_xfer *xfer, usb_error_t error)
   {
           struct uchcom_softc *sc = usbd_xfer_softc(xfer);
           struct usb_page_cache *pc;
           int actlen;
   
           usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
   
           switch (USB_GET_STATE(xfer)) {
           case USB_ST_TRANSFERRED:
   
                   if (actlen > 0) {
                           pc = usbd_xfer_get_frame(xfer, 0);
                           ucom_put_data(&sc->sc_ucom, pc, 0, actlen);
                   }
   
           case USB_ST_SETUP:
   tr_setup:
                   usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
                   usbd_transfer_submit(xfer);
                   break;
   
           default:                        /* Error */
                   if (error != USB_ERR_CANCELLED) {
                           /* try to clear stall first */
                           usbd_xfer_set_stall(xfer);
                           goto tr_setup;
                   }
                   break;
           }
   }
   
   static void
   uchcom_poll(struct ucom_softc *ucom)
   {
           struct uchcom_softc *sc = ucom->sc_parent;
           usbd_transfer_poll(sc->sc_xfer, UCHCOM_N_TRANSFER);
   }
   
   static device_method_t uchcom_methods[] = {
           /* Device interface */
           DEVMETHOD(device_probe, uchcom_probe),
           DEVMETHOD(device_attach, uchcom_attach),
           DEVMETHOD(device_detach, uchcom_detach),
           DEVMETHOD_END
   };
   
   static driver_t uchcom_driver = {
           .name = "uchcom",
           .methods = uchcom_methods,
           .size = sizeof(struct uchcom_softc)
   };
   
   DRIVER_MODULE(uchcom, uhub, uchcom_driver, NULL, NULL);
   MODULE_DEPEND(uchcom, ucom, 1, 1, 1);
   MODULE_DEPEND(uchcom, usb, 1, 1, 1);
   MODULE_VERSION(uchcom, 1);
   USB_PNP_HOST_INFO(uchcom_devs);

Cache object: 91bfb5f67fb72582e85054e76133802e