text: /*	$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/cdefs.h>
  __FBSDID("$FreeBSD: head/sys/dev/usb/misc/ugold.c 292080 2015-12-11 05:28:00Z imp $");
  
  #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/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 devclass_t ugold_devclass;
  
  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, ugold_devclass, NULL, NULL);
  MODULE_DEPEND(ugold, usb, 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(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, 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 microCelcius");
  
  	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 microCelcius");
  	
  	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 microCelcius");
  
  	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 microCelcius");
  
  	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);
  }
  