/*      $OpenBSD: ugold.c,v 1.7 2014/12/11 18:39:27 mpi Exp $   */

/*
 * Copyright (c) 2013 Takayoshi SASANO <sasano@openbsd.org>
 * Copyright (c) 2013 Martin Pieuchot <mpi@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/* Driver for Microdia's HID based TEMPer Temperature sensor */

#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 <sys/conf.h>

#include <dev/hid/hid.h>

#include <dev/usb/usb.h>
#include <dev/usb/usbdi.h>
#include <dev/usb/usbhid.h>
#include <dev/usb/usb_process.h>
#include <dev/usb/usbdi_util.h>
#include "usbdevs.h"

#define USB_DEBUG_VAR usb_debug
#include <dev/usb/usb_debug.h>

#define UGOLD_INNER             0
#define UGOLD_OUTER             1
#define UGOLD_MAX_SENSORS       2

#define UGOLD_CMD_DATA          0x80
#define UGOLD_CMD_INIT          0x82

enum {
        UGOLD_INTR_DT,
        UGOLD_N_TRANSFER,
};

/*
 * This driver only uses two of the three known commands for the
 * TEMPerV1.2 device.
 *
 * The first byte of the answer corresponds to the command and the
 * second one seems to be the size (in bytes) of the answer.
 *
 * The device always sends 8 bytes and if the length of the answer
 * is less than that, it just leaves the last bytes untouched.  That
 * is why most of the time the last n bytes of the answers are the
 * same.
 *
 * The third command below seems to generate two answers with a
 * string corresponding to the device, for example:
 *      'TEMPer1F' and '1.1Per1F' (here Per1F is repeated).
 */
static uint8_t cmd_data[8] = {0x01, 0x80, 0x33, 0x01, 0x00, 0x00, 0x00, 0x00};
static uint8_t cmd_init[8] = {0x01, 0x82, 0x77, 0x01, 0x00, 0x00, 0x00, 0x00};

#if 0
static uint8_t cmd_type[8] = {0x01, 0x86, 0xff, 0x01, 0x00, 0x00, 0x00, 0x00};

#endif

struct ugold_softc;
struct ugold_readout_msg {
        struct usb_proc_msg hdr;
        struct ugold_softc *sc;
};

struct ugold_softc {
        struct usb_device *sc_udev;
        struct usb_xfer *sc_xfer[UGOLD_N_TRANSFER];

        struct callout sc_callout;
        struct mtx sc_mtx;
        struct ugold_readout_msg sc_readout_msg[2];

        int     sc_num_sensors;
        int     sc_sensor[UGOLD_MAX_SENSORS];
        int     sc_calib[UGOLD_MAX_SENSORS];
        int     sc_valid[UGOLD_MAX_SENSORS];
        uint8_t sc_report_id;
        uint8_t sc_iface_index[2];
};

/* prototypes */

static device_probe_t ugold_probe;
static device_attach_t ugold_attach;
static device_detach_t ugold_detach;

static usb_proc_callback_t ugold_readout_msg;

static usb_callback_t ugold_intr_callback;

static device_method_t ugold_methods[] = {
        DEVMETHOD(device_probe, ugold_probe),
        DEVMETHOD(device_attach, ugold_attach),
        DEVMETHOD(device_detach, ugold_detach),

        DEVMETHOD_END
};

static driver_t ugold_driver = {
        .name = "ugold",
        .methods = ugold_methods,
        .size = sizeof(struct ugold_softc),
};

static const STRUCT_USB_HOST_ID ugold_devs[] = {
        {USB_VPI(USB_VENDOR_CHICONY2, USB_PRODUCT_CHICONY2_TEMPER, 0)},
};

DRIVER_MODULE(ugold, uhub, ugold_driver, NULL, NULL);
MODULE_DEPEND(ugold, usb, 1, 1, 1);
MODULE_DEPEND(ugold, hid, 1, 1, 1);
MODULE_VERSION(ugold, 1);
USB_PNP_HOST_INFO(ugold_devs);

static const struct usb_config ugold_config[UGOLD_N_TRANSFER] = {
        [UGOLD_INTR_DT] = {
                .type = UE_INTERRUPT,
                .endpoint = UE_ADDR_ANY,
                .direction = UE_DIR_IN,
                .flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
                .bufsize = 0,           /* use wMaxPacketSize */
                .callback = &ugold_intr_callback,
                .if_index = 1,
        },
};

static void
ugold_timeout(void *arg)
{
        struct ugold_softc *sc = arg;

        usb_proc_explore_lock(sc->sc_udev);
        (void)usb_proc_explore_msignal(sc->sc_udev,
            &sc->sc_readout_msg[0], &sc->sc_readout_msg[1]);
        usb_proc_explore_unlock(sc->sc_udev);

        callout_reset(&sc->sc_callout, 6 * hz, &ugold_timeout, sc);
}

static int
ugold_probe(device_t dev)
{
        struct usb_attach_arg *uaa;

        uaa = device_get_ivars(dev);
        if (uaa->usb_mode != USB_MODE_HOST)
                return (ENXIO);
        if (uaa->info.bInterfaceClass != UICLASS_HID)
                return (ENXIO);
        if (uaa->info.bIfaceIndex != 0)
                return (ENXIO);

        return (usbd_lookup_id_by_uaa(ugold_devs, sizeof(ugold_devs), uaa));
}

static int
ugold_attach(device_t dev)
{
        struct ugold_softc *sc = device_get_softc(dev);
        struct usb_attach_arg *uaa = device_get_ivars(dev);
        struct sysctl_oid *sensor_tree;
        uint16_t d_len;
        void *d_ptr;
        int error;
        int i;

        sc->sc_udev = uaa->device;
        sc->sc_readout_msg[0].hdr.pm_callback = &ugold_readout_msg;
        sc->sc_readout_msg[0].sc = sc;
        sc->sc_readout_msg[1].hdr.pm_callback = &ugold_readout_msg;
        sc->sc_readout_msg[1].sc = sc;
        sc->sc_iface_index[0] = uaa->info.bIfaceIndex;
        sc->sc_iface_index[1] = uaa->info.bIfaceIndex + 1;

        device_set_usb_desc(dev);
        mtx_init(&sc->sc_mtx, "ugold lock", NULL, MTX_DEF | MTX_RECURSE);
        callout_init_mtx(&sc->sc_callout, &sc->sc_mtx, 0);

        /* grab all interfaces from other drivers */
        for (i = 0;; i++) {
                if (i == uaa->info.bIfaceIndex)
                        continue;
                if (usbd_get_iface(uaa->device, i) == NULL)
                        break;

                usbd_set_parent_iface(uaa->device, i, uaa->info.bIfaceIndex);
        }

        /* figure out report ID */
        error = usbd_req_get_hid_desc(uaa->device, NULL,
            &d_ptr, &d_len, M_TEMP, uaa->info.bIfaceIndex);

        if (error)
                goto detach;

        (void)hid_report_size_max(d_ptr, d_len, hid_input, &sc->sc_report_id);

        free(d_ptr, M_TEMP);

        error = usbd_transfer_setup(uaa->device,
            sc->sc_iface_index, sc->sc_xfer, ugold_config,
            UGOLD_N_TRANSFER, sc, &sc->sc_mtx);
        if (error)
                goto detach;

        sensor_tree = SYSCTL_ADD_NODE(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "sensors",
            CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");

        if (sensor_tree == NULL) {
                error = ENOMEM;
                goto detach;
        }
        SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(sensor_tree),
            OID_AUTO, "inner", CTLFLAG_RD, &sc->sc_sensor[UGOLD_INNER], 0,
            "Inner temperature in microCelsius");

        SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(sensor_tree),
            OID_AUTO, "inner_valid", CTLFLAG_RD, &sc->sc_valid[UGOLD_INNER], 0,
            "Inner temperature is valid");

        SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(sensor_tree),
            OID_AUTO, "inner_calib", CTLFLAG_RWTUN, &sc->sc_calib[UGOLD_INNER], 0,
            "Inner calibration temperature in microCelsius");

        SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(sensor_tree),
            OID_AUTO, "outer", CTLFLAG_RD, &sc->sc_sensor[UGOLD_OUTER], 0,
            "Outer temperature in microCelsius");

        SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(sensor_tree),
            OID_AUTO, "outer_calib", CTLFLAG_RWTUN, &sc->sc_calib[UGOLD_OUTER], 0,
            "Outer calibration temperature in microCelsius");

        SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
            SYSCTL_CHILDREN(sensor_tree),
            OID_AUTO, "outer_valid", CTLFLAG_RD, &sc->sc_valid[UGOLD_OUTER], 0,
            "Outer temperature is valid");

        mtx_lock(&sc->sc_mtx);
        usbd_transfer_start(sc->sc_xfer[UGOLD_INTR_DT]);
        ugold_timeout(sc);
        mtx_unlock(&sc->sc_mtx);

        return (0);

detach:
        DPRINTF("error=%s\n", usbd_errstr(error));
        ugold_detach(dev);
        return (error);
}

static int
ugold_detach(device_t dev)
{
        struct ugold_softc *sc = device_get_softc(dev);

        callout_drain(&sc->sc_callout);

        usb_proc_explore_lock(sc->sc_udev);
        usb_proc_explore_mwait(sc->sc_udev,
            &sc->sc_readout_msg[0], &sc->sc_readout_msg[1]);
        usb_proc_explore_unlock(sc->sc_udev);

        usbd_transfer_unsetup(sc->sc_xfer, UGOLD_N_TRANSFER);

        mtx_destroy(&sc->sc_mtx);

        return (0);
}

static int
ugold_ds75_temp(uint8_t msb, uint8_t lsb)
{
        /* DS75: 12bit precision mode : 0.0625 degrees Celsius ticks */
        /* NOTE: MSB has a sign bit for negative temperatures */
        int32_t temp = (msb << 24) | ((lsb & 0xF0) << 16);
        return (((int64_t)temp * (int64_t)1000000LL) >> 24);
}

static void
ugold_intr_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct ugold_softc *sc = usbd_xfer_softc(xfer);
        struct usb_page_cache *pc;
        uint8_t buf[8];
        int temp;
        int len;

        usbd_xfer_status(xfer, &len, NULL, NULL, NULL);

        switch (USB_GET_STATE(xfer)) {
        case USB_ST_TRANSFERRED:
                memset(buf, 0, sizeof(buf));

                pc = usbd_xfer_get_frame(xfer, 0);
                usbd_copy_out(pc, 0, buf, MIN(len, sizeof(buf)));

                switch (buf[0]) {
                case UGOLD_CMD_INIT:
                        if (sc->sc_num_sensors)
                                break;

                        sc->sc_num_sensors = MIN(buf[1], UGOLD_MAX_SENSORS) /* XXX */ ;

                        DPRINTF("%d sensor%s type ds75/12bit (temperature)\n",
                            sc->sc_num_sensors, (sc->sc_num_sensors == 1) ? "" : "s");
                        break;
                case UGOLD_CMD_DATA:
                        switch (buf[1]) {
                        case 4:
                                temp = ugold_ds75_temp(buf[4], buf[5]);
                                sc->sc_sensor[UGOLD_OUTER] = temp + sc->sc_calib[UGOLD_OUTER];
                                sc->sc_valid[UGOLD_OUTER] = 1;
                                /* FALLTHROUGH */
                        case 2:
                                temp = ugold_ds75_temp(buf[2], buf[3]);
                                sc->sc_sensor[UGOLD_INNER] = temp + sc->sc_calib[UGOLD_INNER];
                                sc->sc_valid[UGOLD_INNER] = 1;
                                break;
                        default:
                                DPRINTF("invalid data length (%d bytes)\n", buf[1]);
                        }
                        break;
                default:
                        DPRINTF("unknown command 0x%02x\n", buf[0]);
                        break;
                }
                /* FALLTHROUGH */
        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 clear stall first */
                        usbd_xfer_set_stall(xfer);
                        goto tr_setup;
                }
                break;
        }
}

static int
ugold_issue_cmd(struct ugold_softc *sc, uint8_t *cmd, int len)
{
        return (usbd_req_set_report(sc->sc_udev, &sc->sc_mtx, cmd, len,
            sc->sc_iface_index[1], UHID_OUTPUT_REPORT, sc->sc_report_id));
}

static void
ugold_readout_msg(struct usb_proc_msg *pm)
{
        struct ugold_softc *sc = ((struct ugold_readout_msg *)pm)->sc;

        usb_proc_explore_unlock(sc->sc_udev);

        mtx_lock(&sc->sc_mtx);
        if (sc->sc_num_sensors == 0)
                ugold_issue_cmd(sc, cmd_init, sizeof(cmd_init));

        ugold_issue_cmd(sc, cmd_data, sizeof(cmd_data));
        mtx_unlock(&sc->sc_mtx);

        usb_proc_explore_lock(sc->sc_udev);
}