Quelle  hid-pidff.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Force feedback driver for USB HID PID compliant devices
 *
 *  Copyright (c) 2005, 2006 Anssi Hannula <anssi.hannula@gmail.com>
 *  Upgraded 2025 by Oleg Makarenko and Tomasz Pakuła
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include "hid-pidff.h"
#include <linux/input.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/hid.h>
#include <linux/minmax.h>


#define PID_EFFECTS_MAX  64
#define PID_INFINITE  U16_MAX

/* Linux Force Feedback API uses miliseconds as time unit */
#define FF_TIME_EXPONENT -3
#define FF_INFINITE  0

/* Report usage table used to put reports into an array */
#define PID_SET_EFFECT  0
#define PID_EFFECT_OPERATION 1
#define PID_DEVICE_GAIN  2
#define PID_POOL  3
#define PID_BLOCK_LOAD  4
#define PID_BLOCK_FREE  5
#define PID_DEVICE_CONTROL 6
#define PID_CREATE_NEW_EFFECT 7

#define PID_REQUIRED_REPORTS 7

#define PID_SET_ENVELOPE 8
#define PID_SET_CONDITION 9
#define PID_SET_PERIODIC 10
#define PID_SET_CONSTANT 11
#define PID_SET_RAMP  12
static const u8 pidff_reports[] = {
 0x21, 0x77, 0x7d, 0x7f, 0x89, 0x90, 0x96, 0xab,
 0x5a, 0x5f, 0x6e, 0x73, 0x74
};
/*
 * device_control is really 0x95, but 0x96 specified
 * as it is the usage of the only field in that report.
 */

/* PID special fields */
#define PID_EFFECT_TYPE   0x25
#define PID_DIRECTION   0x57
#define PID_EFFECT_OPERATION_ARRAY 0x78
#define PID_BLOCK_LOAD_STATUS  0x8b
#define PID_DEVICE_CONTROL_ARRAY 0x96

/* Value usage tables used to put fields and values into arrays */
#define PID_EFFECT_BLOCK_INDEX 0

#define PID_DURATION  1
#define PID_GAIN  2
#define PID_TRIGGER_BUTTON 3
#define PID_TRIGGER_REPEAT_INT 4
#define PID_DIRECTION_ENABLE 5
#define PID_START_DELAY  6
static const u8 pidff_set_effect[] = {
 0x22, 0x50, 0x52, 0x53, 0x54, 0x56, 0xa7
};

#define PID_ATTACK_LEVEL 1
#define PID_ATTACK_TIME  2
#define PID_FADE_LEVEL  3
#define PID_FADE_TIME  4
static const u8 pidff_set_envelope[] = { 0x22, 0x5b, 0x5c, 0x5d, 0x5e };

#define PID_PARAM_BLOCK_OFFSET 1
#define PID_CP_OFFSET  2
#define PID_POS_COEFFICIENT 3
#define PID_NEG_COEFFICIENT 4
#define PID_POS_SATURATION 5
#define PID_NEG_SATURATION 6
#define PID_DEAD_BAND  7
static const u8 pidff_set_condition[] = {
 0x22, 0x23, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65
};

#define PID_MAGNITUDE  1
#define PID_OFFSET  2
#define PID_PHASE  3
#define PID_PERIOD  4
static const u8 pidff_set_periodic[] = { 0x22, 0x70, 0x6f, 0x71, 0x72 };
static const u8 pidff_set_constant[] = { 0x22, 0x70 };

#define PID_RAMP_START  1
#define PID_RAMP_END  2
static const u8 pidff_set_ramp[] = { 0x22, 0x75, 0x76 };

#define PID_RAM_POOL_AVAILABLE 1
static const u8 pidff_block_load[] = { 0x22, 0xac };

#define PID_LOOP_COUNT  1
static const u8 pidff_effect_operation[] = { 0x22, 0x7c };

static const u8 pidff_block_free[] = { 0x22 };

#define PID_DEVICE_GAIN_FIELD 0
static const u8 pidff_device_gain[] = { 0x7e };

#define PID_RAM_POOL_SIZE 0
#define PID_SIMULTANEOUS_MAX 1
#define PID_DEVICE_MANAGED_POOL 2
static const u8 pidff_pool[] = { 0x80, 0x83, 0xa9 };

/* Special field key tables used to put special field keys into arrays */
#define PID_ENABLE_ACTUATORS 0
#define PID_DISABLE_ACTUATORS 1
#define PID_STOP_ALL_EFFECTS 2
#define PID_RESET  3
#define PID_PAUSE  4
#define PID_CONTINUE  5
static const u8 pidff_device_control[] = { 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9c };

#define PID_CONSTANT 0
#define PID_RAMP 1
#define PID_SQUARE 2
#define PID_SINE 3
#define PID_TRIANGLE 4
#define PID_SAW_UP 5
#define PID_SAW_DOWN 6
#define PID_SPRING 7
#define PID_DAMPER 8
#define PID_INERTIA 9
#define PID_FRICTION 10
static const u8 pidff_effect_types[] = {
 0x26, 0x27, 0x30, 0x31, 0x32, 0x33, 0x34,
 0x40, 0x41, 0x42, 0x43
};

#define PID_BLOCK_LOAD_SUCCESS 0
#define PID_BLOCK_LOAD_FULL 1
#define PID_BLOCK_LOAD_ERROR 2
static const u8 pidff_block_load_status[] = { 0x8c, 0x8d, 0x8e};

#define PID_EFFECT_START 0
#define PID_EFFECT_STOP  1
static const u8 pidff_effect_operation_status[] = { 0x79, 0x7b };

/* Polar direction 90 degrees (East) */
#define PIDFF_FIXED_WHEEL_DIRECTION 0x4000

struct pidff_usage {
 struct hid_field *field;
 s32 *value;
};

struct pidff_device {
 struct hid_device *hid;

 struct hid_report *reports[sizeof(pidff_reports)];

 struct pidff_usage set_effect[sizeof(pidff_set_effect)];
 struct pidff_usage set_envelope[sizeof(pidff_set_envelope)];
 struct pidff_usage set_condition[sizeof(pidff_set_condition)];
 struct pidff_usage set_periodic[sizeof(pidff_set_periodic)];
 struct pidff_usage set_constant[sizeof(pidff_set_constant)];
 struct pidff_usage set_ramp[sizeof(pidff_set_ramp)];

 struct pidff_usage device_gain[sizeof(pidff_device_gain)];
 struct pidff_usage block_load[sizeof(pidff_block_load)];
 struct pidff_usage pool[sizeof(pidff_pool)];
 struct pidff_usage effect_operation[sizeof(pidff_effect_operation)];
 struct pidff_usage block_free[sizeof(pidff_block_free)];

 /*
 * Special field is a field that is not composed of
 * usage<->value pairs that pidff_usage values are
 */

 /* Special field in create_new_effect */
 struct hid_field *create_new_effect_type;

 /* Special fields in set_effect */
 struct hid_field *set_effect_type;
 struct hid_field *effect_direction;

 /* Special field in device_control */
 struct hid_field *device_control;

 /* Special field in block_load */
 struct hid_field *block_load_status;

 /* Special field in effect_operation */
 struct hid_field *effect_operation_status;

 int control_id[sizeof(pidff_device_control)];
 int type_id[sizeof(pidff_effect_types)];
 int status_id[sizeof(pidff_block_load_status)];
 int operation_id[sizeof(pidff_effect_operation_status)];

 int pid_id[PID_EFFECTS_MAX];

 u32 quirks;
 u8 effect_count;
};

static int pidff_is_effect_conditional(struct ff_effect *effect)
{
 return effect->type == FF_SPRING  ||
        effect->type == FF_DAMPER  ||
        effect->type == FF_INERTIA ||
        effect->type == FF_FRICTION;
}

/*
 * Clamp value for a given field
 */
static s32 pidff_clamp(s32 i, struct hid_field *field)
{
 return (s32)clamp(i, field->logical_minimum, field->logical_maximum);
}

/*
 * Scale an unsigned value with range 0..max for the given field
 */
static int pidff_rescale(int i, int max, struct hid_field *field)
{
 return i * (field->logical_maximum - field->logical_minimum) / max +
  field->logical_minimum;
}

/*
 * Scale a signed value in range S16_MIN..S16_MAX for the given field
 */
static int pidff_rescale_signed(int i, struct hid_field *field)
{
 if (i > 0)
  return i * field->logical_maximum / S16_MAX;
 if (i < 0)
  return i * field->logical_minimum / S16_MIN;
 return 0;
}

/*
 * Scale time value from Linux default (ms) to field units
 */
static u32 pidff_rescale_time(u16 time, struct hid_field *field)
{
 u32 scaled_time = time;
 int exponent = field->unit_exponent;

 pr_debug("time field exponent: %d\n", exponent);
 for (; exponent < FF_TIME_EXPONENT; exponent++)
  scaled_time *= 10;
 for (; exponent > FF_TIME_EXPONENT; exponent--)
  scaled_time /= 10;

 pr_debug("time calculated from %d to %d\n", time, scaled_time);
 return scaled_time;
}

static void pidff_set(struct pidff_usage *usage, u16 value)
{
 usage->value[0] = pidff_rescale(value, U16_MAX, usage->field);
 pr_debug("calculated from %d to %d\n", value, usage->value[0]);
}

static void pidff_set_signed(struct pidff_usage *usage, s16 value)
{
 if (usage->field->logical_minimum < 0)
  usage->value[0] = pidff_rescale_signed(value, usage->field);
 else {
  if (value < 0)
   usage->value[0] =
       pidff_rescale(-value, -S16_MIN, usage->field);
  else
   usage->value[0] =
       pidff_rescale(value, S16_MAX, usage->field);
 }
 pr_debug("calculated from %d to %d\n", value, usage->value[0]);
}

static void pidff_set_time(struct pidff_usage *usage, u16 time)
{
 usage->value[0] = pidff_clamp(
  pidff_rescale_time(time, usage->field), usage->field);
}

static void pidff_set_duration(struct pidff_usage *usage, u16 duration)
{
 /* Infinite value conversion from Linux API -> PID */
 if (duration == FF_INFINITE)
  duration = PID_INFINITE;

 /* PID defines INFINITE as the max possible value for duration field */
 if (duration == PID_INFINITE) {
  usage->value[0] = (1U << usage->field->report_size) - 1;
  return;
 }

 pidff_set_time(usage, duration);
}

static void pidff_set_effect_direction(struct pidff_device *pidff,
           struct ff_effect *effect)
{
 u16 direction = effect->direction;

 /* Use fixed direction if needed */
 if (pidff->quirks & HID_PIDFF_QUIRK_FIX_CONDITIONAL_DIRECTION &&
     pidff_is_effect_conditional(effect))
  direction = PIDFF_FIXED_WHEEL_DIRECTION;

 pidff->effect_direction->value[0] =
  pidff_rescale(direction, U16_MAX, pidff->effect_direction);
}

/*
 * Send envelope report to the device
 */
static void pidff_set_envelope_report(struct pidff_device *pidff,
          struct ff_envelope *envelope)
{
 pidff->set_envelope[PID_EFFECT_BLOCK_INDEX].value[0] =
  pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];

 pidff->set_envelope[PID_ATTACK_LEVEL].value[0] =
  pidff_rescale(envelope->attack_level >
   S16_MAX ? S16_MAX : envelope->attack_level, S16_MAX,
   pidff->set_envelope[PID_ATTACK_LEVEL].field);
 pidff->set_envelope[PID_FADE_LEVEL].value[0] =
  pidff_rescale(envelope->fade_level >
   S16_MAX ? S16_MAX : envelope->fade_level, S16_MAX,
   pidff->set_envelope[PID_FADE_LEVEL].field);

 pidff_set_time(&pidff->set_envelope[PID_ATTACK_TIME],
   envelope->attack_length);
 pidff_set_time(&pidff->set_envelope[PID_FADE_TIME],
   envelope->fade_length);

 hid_dbg(pidff->hid, "attack %u => %d\n",
  envelope->attack_level,
  pidff->set_envelope[PID_ATTACK_LEVEL].value[0]);

 hid_hw_request(pidff->hid, pidff->reports[PID_SET_ENVELOPE],
   HID_REQ_SET_REPORT);
}

/*
 * Test if the new envelope differs from old one
 */
static int pidff_needs_set_envelope(struct ff_envelope *envelope,
        struct ff_envelope *old)
{
 bool needs_new_envelope;

 needs_new_envelope = envelope->attack_level  != 0 ||
        envelope->fade_level    != 0 ||
        envelope->attack_length != 0 ||
        envelope->fade_length   != 0;

 if (!needs_new_envelope)
  return false;

 if (!old)
  return needs_new_envelope;

 return envelope->attack_level  != old->attack_level  ||
        envelope->fade_level    != old->fade_level    ||
        envelope->attack_length != old->attack_length ||
        envelope->fade_length   != old->fade_length;
}

/*
 * Send constant force report to the device
 */
static void pidff_set_constant_force_report(struct pidff_device *pidff,
         struct ff_effect *effect)
{
 pidff->set_constant[PID_EFFECT_BLOCK_INDEX].value[0] =
  pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 pidff_set_signed(&pidff->set_constant[PID_MAGNITUDE],
    effect->u.constant.level);

 hid_hw_request(pidff->hid, pidff->reports[PID_SET_CONSTANT],
   HID_REQ_SET_REPORT);
}

/*
 * Test if the constant parameters have changed between effects
 */
static int pidff_needs_set_constant(struct ff_effect *effect,
        struct ff_effect *old)
{
 return effect->u.constant.level != old->u.constant.level;
}

/*
 * Send set effect report to the device
 */
static void pidff_set_effect_report(struct pidff_device *pidff,
        struct ff_effect *effect)
{
 pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
  pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 pidff->set_effect_type->value[0] =
  pidff->create_new_effect_type->value[0];

 pidff_set_duration(&pidff->set_effect[PID_DURATION],
  effect->replay.length);

 pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = effect->trigger.button;
 pidff_set_time(&pidff->set_effect[PID_TRIGGER_REPEAT_INT],
   effect->trigger.interval);
 pidff->set_effect[PID_GAIN].value[0] =
  pidff->set_effect[PID_GAIN].field->logical_maximum;
 pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;

 pidff_set_effect_direction(pidff, effect);

 /* Omit setting delay field if it's missing */
 if (!(pidff->quirks & HID_PIDFF_QUIRK_MISSING_DELAY))
  pidff_set_time(&pidff->set_effect[PID_START_DELAY],
    effect->replay.delay);

 hid_hw_request(pidff->hid, pidff->reports[PID_SET_EFFECT],
   HID_REQ_SET_REPORT);
}

/*
 * Test if the values used in set_effect have changed
 */
static int pidff_needs_set_effect(struct ff_effect *effect,
      struct ff_effect *old)
{
 return effect->replay.length != old->replay.length ||
        effect->trigger.interval != old->trigger.interval ||
        effect->trigger.button != old->trigger.button ||
        effect->direction != old->direction ||
        effect->replay.delay != old->replay.delay;
}

/*
 * Send periodic effect report to the device
 */
static void pidff_set_periodic_report(struct pidff_device *pidff,
          struct ff_effect *effect)
{
 pidff->set_periodic[PID_EFFECT_BLOCK_INDEX].value[0] =
  pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 pidff_set_signed(&pidff->set_periodic[PID_MAGNITUDE],
    effect->u.periodic.magnitude);
 pidff_set_signed(&pidff->set_periodic[PID_OFFSET],
    effect->u.periodic.offset);
 pidff_set(&pidff->set_periodic[PID_PHASE], effect->u.periodic.phase);
 pidff_set_time(&pidff->set_periodic[PID_PERIOD],
   effect->u.periodic.period);

 hid_hw_request(pidff->hid, pidff->reports[PID_SET_PERIODIC],
   HID_REQ_SET_REPORT);
}

/*
 * Test if periodic effect parameters have changed
 */
static int pidff_needs_set_periodic(struct ff_effect *effect,
        struct ff_effect *old)
{
 return effect->u.periodic.magnitude != old->u.periodic.magnitude ||
        effect->u.periodic.offset != old->u.periodic.offset ||
        effect->u.periodic.phase != old->u.periodic.phase ||
        effect->u.periodic.period != old->u.periodic.period;
}

/*
 * Send condition effect reports to the device
 */
static void pidff_set_condition_report(struct pidff_device *pidff,
           struct ff_effect *effect)
{
 int i, max_axis;

 /* Devices missing Parameter Block Offset can only have one axis */
 max_axis = pidff->quirks & HID_PIDFF_QUIRK_MISSING_PBO ? 1 : 2;

 pidff->set_condition[PID_EFFECT_BLOCK_INDEX].value[0] =
  pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];

 for (i = 0; i < max_axis; i++) {
  /* Omit Parameter Block Offset if missing */
  if (!(pidff->quirks & HID_PIDFF_QUIRK_MISSING_PBO))
   pidff->set_condition[PID_PARAM_BLOCK_OFFSET].value[0] = i;

  pidff_set_signed(&pidff->set_condition[PID_CP_OFFSET],
     effect->u.condition[i].center);
  pidff_set_signed(&pidff->set_condition[PID_POS_COEFFICIENT],
     effect->u.condition[i].right_coeff);
  pidff_set_signed(&pidff->set_condition[PID_NEG_COEFFICIENT],
     effect->u.condition[i].left_coeff);
  pidff_set(&pidff->set_condition[PID_POS_SATURATION],
     effect->u.condition[i].right_saturation);
  pidff_set(&pidff->set_condition[PID_NEG_SATURATION],
     effect->u.condition[i].left_saturation);
  pidff_set(&pidff->set_condition[PID_DEAD_BAND],
     effect->u.condition[i].deadband);
  hid_hw_request(pidff->hid, pidff->reports[PID_SET_CONDITION],
    HID_REQ_SET_REPORT);
 }
}

/*
 * Test if condition effect parameters have changed
 */
static int pidff_needs_set_condition(struct ff_effect *effect,
         struct ff_effect *old)
{
 int i;
 int ret = 0;

 for (i = 0; i < 2; i++) {
  struct ff_condition_effect *cond = &effect->u.condition[i];
  struct ff_condition_effect *old_cond = &old->u.condition[i];

  ret |= cond->center != old_cond->center ||
         cond->right_coeff != old_cond->right_coeff ||
         cond->left_coeff != old_cond->left_coeff ||
         cond->right_saturation != old_cond->right_saturation ||
         cond->left_saturation != old_cond->left_saturation ||
         cond->deadband != old_cond->deadband;
 }

 return ret;
}

/*
 * Send ramp force report to the device
 */
static void pidff_set_ramp_force_report(struct pidff_device *pidff,
     struct ff_effect *effect)
{
 pidff->set_ramp[PID_EFFECT_BLOCK_INDEX].value[0] =
  pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
 pidff_set_signed(&pidff->set_ramp[PID_RAMP_START],
    effect->u.ramp.start_level);
 pidff_set_signed(&pidff->set_ramp[PID_RAMP_END],
    effect->u.ramp.end_level);
 hid_hw_request(pidff->hid, pidff->reports[PID_SET_RAMP],
   HID_REQ_SET_REPORT);
}

/*
 * Test if ramp force parameters have changed
 */
static int pidff_needs_set_ramp(struct ff_effect *effect, struct ff_effect *old)
{
 return effect->u.ramp.start_level != old->u.ramp.start_level ||
        effect->u.ramp.end_level != old->u.ramp.end_level;
}

/*
 * Set device gain
 */
static void pidff_set_gain_report(struct pidff_device *pidff, u16 gain)
{
 if (!pidff->device_gain[PID_DEVICE_GAIN_FIELD].field)
  return;

 pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], gain);
 hid_hw_request(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
   HID_REQ_SET_REPORT);
}

/*
 * Send device control report to the device
 */
static void pidff_set_device_control(struct pidff_device *pidff, int field)
{
 int i, index;
 int field_index = pidff->control_id[field];

 if (field_index < 1)
  return;

 /* Detect if the field is a bitmask variable or an array */
 if (pidff->device_control->flags & HID_MAIN_ITEM_VARIABLE) {
  hid_dbg(pidff->hid, "DEVICE_CONTROL is a bitmask\n");

  /* Clear current bitmask */
  for (i = 0; i < sizeof(pidff_device_control); i++) {
   index = pidff->control_id[i];
   if (index < 1)
    continue;

   pidff->device_control->value[index - 1] = 0;
  }

  pidff->device_control->value[field_index - 1] = 1;
 } else {
  hid_dbg(pidff->hid, "DEVICE_CONTROL is an array\n");
  pidff->device_control->value[0] = field_index;
 }

 hid_hw_request(pidff->hid, pidff->reports[PID_DEVICE_CONTROL], HID_REQ_SET_REPORT);
 hid_hw_wait(pidff->hid);
}

/*
 * Modify actuators state
 */
static void pidff_set_actuators(struct pidff_device *pidff, bool enable)
{
 hid_dbg(pidff->hid, "%s actuators\n", enable ? "Enable" : "Disable");
 pidff_set_device_control(pidff,
  enable ? PID_ENABLE_ACTUATORS : PID_DISABLE_ACTUATORS);
}

/*
 * Reset the device, stop all effects, enable actuators
 */
static void pidff_reset(struct pidff_device *pidff)
{
 /* We reset twice as sometimes hid_wait_io isn't waiting long enough */
 pidff_set_device_control(pidff, PID_RESET);
 pidff_set_device_control(pidff, PID_RESET);
 pidff->effect_count = 0;

 pidff_set_device_control(pidff, PID_STOP_ALL_EFFECTS);
 pidff_set_actuators(pidff, 1);
}

/*
 * Fetch pool report
 */
static void pidff_fetch_pool(struct pidff_device *pidff)
{
 int i;
 struct hid_device *hid = pidff->hid;

 /* Repeat if PID_SIMULTANEOUS_MAX < 2 to make sure it's correct */
 for (i = 0; i < 20; i++) {
  hid_hw_request(hid, pidff->reports[PID_POOL], HID_REQ_GET_REPORT);
  hid_hw_wait(hid);

  if (!pidff->pool[PID_SIMULTANEOUS_MAX].value)
   return;
  if (pidff->pool[PID_SIMULTANEOUS_MAX].value[0] >= 2)
   return;
 }
 hid_warn(hid, "device reports %d simultaneous effects\n",
   pidff->pool[PID_SIMULTANEOUS_MAX].value[0]);
}

/*
 * Send a request for effect upload to the device
 *
 * Reset and enable actuators if no effects were present on the device
 *
 * Returns 0 if device reported success, -ENOSPC if the device reported memory
 * is full. Upon unknown response the function will retry for 60 times, if
 * still unsuccessful -EIO is returned.
 */
static int pidff_request_effect_upload(struct pidff_device *pidff, int efnum)
{
 int j;

 if (!pidff->effect_count)
  pidff_reset(pidff);

 pidff->create_new_effect_type->value[0] = efnum;
 hid_hw_request(pidff->hid, pidff->reports[PID_CREATE_NEW_EFFECT],
   HID_REQ_SET_REPORT);
 hid_dbg(pidff->hid, "create_new_effect sent, type: %d\n", efnum);

 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] = 0;
 pidff->block_load_status->value[0] = 0;
 hid_hw_wait(pidff->hid);

 for (j = 0; j < 60; j++) {
  hid_dbg(pidff->hid, "pid_block_load requested\n");
  hid_hw_request(pidff->hid, pidff->reports[PID_BLOCK_LOAD],
    HID_REQ_GET_REPORT);
  hid_hw_wait(pidff->hid);
  if (pidff->block_load_status->value[0] ==
      pidff->status_id[PID_BLOCK_LOAD_SUCCESS]) {
   hid_dbg(pidff->hid, "device reported free memory: %d bytes\n",
     pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
     pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);

   pidff->effect_count++;
   return 0;
  }
  if (pidff->block_load_status->value[0] ==
      pidff->status_id[PID_BLOCK_LOAD_FULL]) {
   hid_dbg(pidff->hid, "not enough memory free: %d bytes\n",
    pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
    pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);
   return -ENOSPC;
  }
  if (pidff->block_load_status->value[0] ==
      pidff->status_id[PID_BLOCK_LOAD_ERROR]) {
   hid_dbg(pidff->hid, "device error during effect creation\n");
   return -EREMOTEIO;
  }
 }
 hid_err(pidff->hid, "pid_block_load failed 60 times\n");
 return -EIO;
}

/*
 * Play the effect with PID id n times
 */
static void pidff_playback_pid(struct pidff_device *pidff, int pid_id, int n)
{
 pidff->effect_operation[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;

 if (n == 0) {
  pidff->effect_operation_status->value[0] =
   pidff->operation_id[PID_EFFECT_STOP];
 } else {
  pidff->effect_operation_status->value[0] =
   pidff->operation_id[PID_EFFECT_START];
  pidff->effect_operation[PID_LOOP_COUNT].value[0] =
   pidff_clamp(n, pidff->effect_operation[PID_LOOP_COUNT].field);
 }

 hid_hw_request(pidff->hid, pidff->reports[PID_EFFECT_OPERATION],
   HID_REQ_SET_REPORT);
}

/*
 * Play the effect with effect id @effect_id for @value times
 */
static int pidff_playback(struct input_dev *dev, int effect_id, int value)
{
 struct pidff_device *pidff = dev->ff->private;

 pidff_playback_pid(pidff, pidff->pid_id[effect_id], value);
 return 0;
}

/*
 * Erase effect with PID id
 * Decrease the device effect counter
 */
static void pidff_erase_pid(struct pidff_device *pidff, int pid_id)
{
 pidff->block_free[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;
 hid_hw_request(pidff->hid, pidff->reports[PID_BLOCK_FREE],
   HID_REQ_SET_REPORT);

 if (pidff->effect_count > 0)
  pidff->effect_count--;
}

/*
 * Stop and erase effect with effect_id
 */
static int pidff_erase_effect(struct input_dev *dev, int effect_id)
{
 struct pidff_device *pidff = dev->ff->private;
 int pid_id = pidff->pid_id[effect_id];

 hid_dbg(pidff->hid, "starting to erase %d/%d\n",
  effect_id, pidff->pid_id[effect_id]);

 /*
 * Wait for the queue to clear. We do not want
 * a full fifo to prevent the effect removal.
 */
 hid_hw_wait(pidff->hid);
 pidff_playback_pid(pidff, pid_id, 0);
 pidff_erase_pid(pidff, pid_id);

 return 0;
}

/*
 * Effect upload handler
 */
static int pidff_upload_effect(struct input_dev *dev, struct ff_effect *effect,
          struct ff_effect *old)
{
 struct pidff_device *pidff = dev->ff->private;
 int type_id;
 int error;

 pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] = 0;
 if (old) {
  pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] =
   pidff->pid_id[effect->id];
 }

 switch (effect->type) {
 case FF_CONSTANT:
  if (!old) {
   error = pidff_request_effect_upload(pidff,
     pidff->type_id[PID_CONSTANT]);
   if (error)
    return error;
  }
  if (!old || pidff_needs_set_effect(effect, old))
   pidff_set_effect_report(pidff, effect);
  if (!old || pidff_needs_set_constant(effect, old))
   pidff_set_constant_force_report(pidff, effect);
  if (pidff_needs_set_envelope(&effect->u.constant.envelope,
     old ? &old->u.constant.envelope : NULL))
   pidff_set_envelope_report(pidff, &effect->u.constant.envelope);
  break;

 case FF_PERIODIC:
  if (!old) {
   switch (effect->u.periodic.waveform) {
   case FF_SQUARE:
    type_id = PID_SQUARE;
    break;
   case FF_TRIANGLE:
    type_id = PID_TRIANGLE;
    break;
   case FF_SINE:
    type_id = PID_SINE;
    break;
   case FF_SAW_UP:
    type_id = PID_SAW_UP;
    break;
   case FF_SAW_DOWN:
    type_id = PID_SAW_DOWN;
    break;
   default:
    hid_err(pidff->hid, "invalid waveform\n");
    return -EINVAL;
   }

   if (pidff->quirks & HID_PIDFF_QUIRK_PERIODIC_SINE_ONLY)
    type_id = PID_SINE;

   error = pidff_request_effect_upload(pidff,
     pidff->type_id[type_id]);
   if (error)
    return error;
  }
  if (!old || pidff_needs_set_effect(effect, old))
   pidff_set_effect_report(pidff, effect);
  if (!old || pidff_needs_set_periodic(effect, old))
   pidff_set_periodic_report(pidff, effect);
  if (pidff_needs_set_envelope(&effect->u.periodic.envelope,
     old ? &old->u.periodic.envelope : NULL))
   pidff_set_envelope_report(pidff, &effect->u.periodic.envelope);
  break;

 case FF_RAMP:
  if (!old) {
   error = pidff_request_effect_upload(pidff,
     pidff->type_id[PID_RAMP]);
   if (error)
    return error;
  }
  if (!old || pidff_needs_set_effect(effect, old))
   pidff_set_effect_report(pidff, effect);
  if (!old || pidff_needs_set_ramp(effect, old))
   pidff_set_ramp_force_report(pidff, effect);
  if (pidff_needs_set_envelope(&effect->u.ramp.envelope,
     old ? &old->u.ramp.envelope : NULL))
   pidff_set_envelope_report(pidff, &effect->u.ramp.envelope);
  break;

 case FF_SPRING:
 case FF_DAMPER:
 case FF_INERTIA:
 case FF_FRICTION:
  if (!old) {
   switch (effect->type) {
   case FF_SPRING:
    type_id = PID_SPRING;
    break;
   case FF_DAMPER:
    type_id = PID_DAMPER;
    break;
   case FF_INERTIA:
    type_id = PID_INERTIA;
    break;
   case FF_FRICTION:
    type_id = PID_FRICTION;
    break;
   }
   error = pidff_request_effect_upload(pidff,
     pidff->type_id[type_id]);
   if (error)
    return error;
  }
  if (!old || pidff_needs_set_effect(effect, old))
   pidff_set_effect_report(pidff, effect);
  if (!old || pidff_needs_set_condition(effect, old))
   pidff_set_condition_report(pidff, effect);
  break;

 default:
  hid_err(pidff->hid, "invalid type\n");
  return -EINVAL;
 }

 if (!old)
  pidff->pid_id[effect->id] =
      pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];

 hid_dbg(pidff->hid, "uploaded\n");

 return 0;
}

/*
 * set_gain() handler
 */
static void pidff_set_gain(struct input_dev *dev, u16 gain)
{
 pidff_set_gain_report(dev->ff->private, gain);
}

static void pidff_autocenter(struct pidff_device *pidff, u16 magnitude)
{
 struct hid_field *field =
  pidff->block_load[PID_EFFECT_BLOCK_INDEX].field;

 if (!magnitude) {
  pidff_playback_pid(pidff, field->logical_minimum, 0);
  return;
 }

 pidff_playback_pid(pidff, field->logical_minimum, 1);

 pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
  pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum;
 pidff->set_effect_type->value[0] = pidff->type_id[PID_SPRING];
 pidff->set_effect[PID_DURATION].value[0] = 0;
 pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = 0;
 pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] = 0;
 pidff_set(&pidff->set_effect[PID_GAIN], magnitude);
 pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;

 /* Omit setting delay field if it's missing */
 if (!(pidff->quirks & HID_PIDFF_QUIRK_MISSING_DELAY))
  pidff->set_effect[PID_START_DELAY].value[0] = 0;

 hid_hw_request(pidff->hid, pidff->reports[PID_SET_EFFECT],
   HID_REQ_SET_REPORT);
}

/*
 * pidff_set_autocenter() handler
 */
static void pidff_set_autocenter(struct input_dev *dev, u16 magnitude)
{
 pidff_autocenter(dev->ff->private, magnitude);
}

/*
 * Find fields from a report and fill a pidff_usage
 */
static int pidff_find_fields(struct pidff_usage *usage, const u8 *table,
        struct hid_report *report, int count, int strict)
{
 if (!report) {
  pr_debug("%s, null report\n", __func__);
  return -1;
 }

 int i, j, k, found;
 int return_value = 0;

 for (k = 0; k < count; k++) {
  found = 0;
  for (i = 0; i < report->maxfield; i++) {
   if (report->field[i]->maxusage !=
       report->field[i]->report_count) {
    pr_debug("maxusage and report_count do not match, skipping\n");
    continue;
   }
   for (j = 0; j < report->field[i]->maxusage; j++) {
    if (report->field[i]->usage[j].hid ==
        (HID_UP_PID | table[k])) {
     pr_debug("found %d at %d->%d\n",
       k, i, j);
     usage[k].field = report->field[i];
     usage[k].value =
      &report->field[i]->value[j];
     found = 1;
     break;
    }
   }
   if (found)
    break;
  }
  if (!found && table[k] == pidff_set_effect[PID_START_DELAY]) {
   pr_debug("Delay field not found, but that's OK\n");
   pr_debug("Setting MISSING_DELAY quirk\n");
   return_value |= HID_PIDFF_QUIRK_MISSING_DELAY;
  } else if (!found && table[k] == pidff_set_condition[PID_PARAM_BLOCK_OFFSET]) {
   pr_debug("PBO field not found, but that's OK\n");
   pr_debug("Setting MISSING_PBO quirk\n");
   return_value |= HID_PIDFF_QUIRK_MISSING_PBO;
  } else if (!found && strict) {
   pr_debug("failed to locate %d\n", k);
   return -1;
  }
 }
 return return_value;
}

/*
 * Return index into pidff_reports for the given usage
 */
static int pidff_check_usage(int usage)
{
 int i;

 for (i = 0; i < sizeof(pidff_reports); i++)
  if (usage == (HID_UP_PID | pidff_reports[i]))
   return i;

 return -1;
}

/*
 * Find the reports and fill pidff->reports[]
 * report_type specifies either OUTPUT or FEATURE reports
 */
static void pidff_find_reports(struct hid_device *hid, int report_type,
          struct pidff_device *pidff)
{
 struct hid_report *report;
 int i, ret;

 list_for_each_entry(report,
       &hid->report_enum[report_type].report_list, list) {
  if (report->maxfield < 1)
   continue;
  ret = pidff_check_usage(report->field[0]->logical);
  if (ret != -1) {
   hid_dbg(hid, "found usage 0x%02x from field->logical\n",
    pidff_reports[ret]);
   pidff->reports[ret] = report;
   continue;
  }

  /*
 * Sometimes logical collections are stacked to indicate
 * different usages for the report and the field, in which
 * case we want the usage of the parent. However, Linux HID
 * implementation hides this fact, so we have to dig it up
 * ourselves
 */
  i = report->field[0]->usage[0].collection_index;
  if (i <= 0 ||
      hid->collection[i - 1].type != HID_COLLECTION_LOGICAL)
   continue;
  ret = pidff_check_usage(hid->collection[i - 1].usage);
  if (ret != -1 && !pidff->reports[ret]) {
   hid_dbg(hid,
    "found usage 0x%02x from collection array\n",
    pidff_reports[ret]);
   pidff->reports[ret] = report;
  }
 }
}

/*
 * Test if the required reports have been found
 */
static int pidff_reports_ok(struct pidff_device *pidff)
{
 int i;

 for (i = 0; i <= PID_REQUIRED_REPORTS; i++) {
  if (!pidff->reports[i]) {
   hid_dbg(pidff->hid, "%d missing\n", i);
   return 0;
  }
 }

 return 1;
}

/*
 * Find a field with a specific usage within a report
 */
static struct hid_field *pidff_find_special_field(struct hid_report *report,
        int usage, int enforce_min)
{
 if (!report) {
  pr_debug("%s, null report\n", __func__);
  return NULL;
 }

 int i;

 for (i = 0; i < report->maxfield; i++) {
  if (report->field[i]->logical == (HID_UP_PID | usage) &&
      report->field[i]->report_count > 0) {
   if (!enforce_min ||
       report->field[i]->logical_minimum == 1)
    return report->field[i];

   pr_err("logical_minimum is not 1 as it should be\n");
   return NULL;
  }
 }
 return NULL;
}

/*
 * Fill a pidff->*_id struct table
 */
static int pidff_find_special_keys(int *keys, struct hid_field *fld,
       const u8 *usagetable, int count)
{

 int i, j;
 int found = 0;

 for (i = 0; i < count; i++) {
  for (j = 0; j < fld->maxusage; j++) {
   if (fld->usage[j].hid == (HID_UP_PID | usagetable[i])) {
    keys[i] = j + 1;
    found++;
    break;
   }
  }
 }
 return found;
}

#define PIDFF_FIND_SPECIAL_KEYS(keys, field, name) \
 pidff_find_special_keys(pidff->keys, pidff->field, pidff_ ## name, \
  sizeof(pidff_ ## name))

/*
 * Find and check the special fields
 */
static int pidff_find_special_fields(struct pidff_device *pidff)
{
 hid_dbg(pidff->hid, "finding special fields\n");

 pidff->create_new_effect_type =
  pidff_find_special_field(pidff->reports[PID_CREATE_NEW_EFFECT],
      PID_EFFECT_TYPE, 1);
 pidff->set_effect_type =
  pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
      PID_EFFECT_TYPE, 1);
 pidff->effect_direction =
  pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
      PID_DIRECTION, 0);
 pidff->device_control =
  pidff_find_special_field(pidff->reports[PID_DEVICE_CONTROL],
   PID_DEVICE_CONTROL_ARRAY, 1);

 /* Detect and set permissive control quirk */
 if (!pidff->device_control) {
  pr_debug("Setting PERMISSIVE_CONTROL quirk\n");
  pidff->quirks |= HID_PIDFF_QUIRK_PERMISSIVE_CONTROL;
  pidff->device_control = pidff_find_special_field(
   pidff->reports[PID_DEVICE_CONTROL],
   PID_DEVICE_CONTROL_ARRAY, 0);
 }

 pidff->block_load_status =
  pidff_find_special_field(pidff->reports[PID_BLOCK_LOAD],
      PID_BLOCK_LOAD_STATUS, 1);
 pidff->effect_operation_status =
  pidff_find_special_field(pidff->reports[PID_EFFECT_OPERATION],
      PID_EFFECT_OPERATION_ARRAY, 1);

 hid_dbg(pidff->hid, "search done\n");

 if (!pidff->create_new_effect_type || !pidff->set_effect_type) {
  hid_err(pidff->hid, "effect lists not found\n");
  return -1;
 }

 if (!pidff->effect_direction) {
  hid_err(pidff->hid, "direction field not found\n");
  return -1;
 }

 if (!pidff->device_control) {
  hid_err(pidff->hid, "device control field not found\n");
  return -1;
 }

 if (!pidff->block_load_status) {
  hid_err(pidff->hid, "block load status field not found\n");
  return -1;
 }

 if (!pidff->effect_operation_status) {
  hid_err(pidff->hid, "effect operation field not found\n");
  return -1;
 }

 PIDFF_FIND_SPECIAL_KEYS(control_id, device_control, device_control);

 if (!PIDFF_FIND_SPECIAL_KEYS(type_id, create_new_effect_type,
         effect_types)) {
  hid_err(pidff->hid, "no effect types found\n");
  return -1;
 }

 if (PIDFF_FIND_SPECIAL_KEYS(status_id, block_load_status,
        block_load_status) !=
   sizeof(pidff_block_load_status)) {
  hid_err(pidff->hid,
   "block load status identifiers not found\n");
  return -1;
 }

 if (PIDFF_FIND_SPECIAL_KEYS(operation_id, effect_operation_status,
        effect_operation_status) !=
   sizeof(pidff_effect_operation_status)) {
  hid_err(pidff->hid, "effect operation identifiers not found\n");
  return -1;
 }

 return 0;
}

/*
 * Find the implemented effect types
 */
static int pidff_find_effects(struct pidff_device *pidff,
         struct input_dev *dev)
{
 int i;

 for (i = 0; i < sizeof(pidff_effect_types); i++) {
  int pidff_type = pidff->type_id[i];

  if (pidff->set_effect_type->usage[pidff_type].hid !=
      pidff->create_new_effect_type->usage[pidff_type].hid) {
   hid_err(pidff->hid,
    "effect type number %d is invalid\n", i);
   return -1;
  }
 }

 if (pidff->type_id[PID_CONSTANT])
  set_bit(FF_CONSTANT, dev->ffbit);
 if (pidff->type_id[PID_RAMP])
  set_bit(FF_RAMP, dev->ffbit);
 if (pidff->type_id[PID_SQUARE]) {
  set_bit(FF_SQUARE, dev->ffbit);
  set_bit(FF_PERIODIC, dev->ffbit);
 }
 if (pidff->type_id[PID_SINE]) {
  set_bit(FF_SINE, dev->ffbit);
  set_bit(FF_PERIODIC, dev->ffbit);
 }
 if (pidff->type_id[PID_TRIANGLE]) {
  set_bit(FF_TRIANGLE, dev->ffbit);
  set_bit(FF_PERIODIC, dev->ffbit);
 }
 if (pidff->type_id[PID_SAW_UP]) {
  set_bit(FF_SAW_UP, dev->ffbit);
  set_bit(FF_PERIODIC, dev->ffbit);
 }
 if (pidff->type_id[PID_SAW_DOWN]) {
  set_bit(FF_SAW_DOWN, dev->ffbit);
  set_bit(FF_PERIODIC, dev->ffbit);
 }
 if (pidff->type_id[PID_SPRING])
  set_bit(FF_SPRING, dev->ffbit);
 if (pidff->type_id[PID_DAMPER])
  set_bit(FF_DAMPER, dev->ffbit);
 if (pidff->type_id[PID_INERTIA])
  set_bit(FF_INERTIA, dev->ffbit);
 if (pidff->type_id[PID_FRICTION])
  set_bit(FF_FRICTION, dev->ffbit);

 return 0;
}

#define PIDFF_FIND_FIELDS(name, report, strict) \
 pidff_find_fields(pidff->name, pidff_ ## name, \
  pidff->reports[report], \
  sizeof(pidff_ ## name), strict)

/*
 * Fill and check the pidff_usages
 */
static int pidff_init_fields(struct pidff_device *pidff, struct input_dev *dev)
{
 int status = 0;

 /* Save info about the device not having the DELAY ffb field. */
 status = PIDFF_FIND_FIELDS(set_effect, PID_SET_EFFECT, 1);
 if (status == -1) {
  hid_err(pidff->hid, "unknown set_effect report layout\n");
  return -ENODEV;
 }
 pidff->quirks |= status;

 if (status & HID_PIDFF_QUIRK_MISSING_DELAY)
  hid_dbg(pidff->hid, "Adding MISSING_DELAY quirk\n");


 PIDFF_FIND_FIELDS(block_load, PID_BLOCK_LOAD, 0);
 if (!pidff->block_load[PID_EFFECT_BLOCK_INDEX].value) {
  hid_err(pidff->hid, "unknown pid_block_load report layout\n");
  return -ENODEV;
 }

 if (PIDFF_FIND_FIELDS(effect_operation, PID_EFFECT_OPERATION, 1)) {
  hid_err(pidff->hid, "unknown effect_operation report layout\n");
  return -ENODEV;
 }

 if (PIDFF_FIND_FIELDS(block_free, PID_BLOCK_FREE, 1)) {
  hid_err(pidff->hid, "unknown pid_block_free report layout\n");
  return -ENODEV;
 }

 if (pidff_find_special_fields(pidff) || pidff_find_effects(pidff, dev))
  return -ENODEV;

 if (PIDFF_FIND_FIELDS(set_envelope, PID_SET_ENVELOPE, 1)) {
  if (test_and_clear_bit(FF_CONSTANT, dev->ffbit))
   hid_warn(pidff->hid,
     "has constant effect but no envelope\n");
  if (test_and_clear_bit(FF_RAMP, dev->ffbit))
   hid_warn(pidff->hid,
     "has ramp effect but no envelope\n");

  if (test_and_clear_bit(FF_PERIODIC, dev->ffbit))
   hid_warn(pidff->hid,
     "has periodic effect but no envelope\n");
 }

 if (test_bit(FF_CONSTANT, dev->ffbit) &&
     PIDFF_FIND_FIELDS(set_constant, PID_SET_CONSTANT, 1)) {
  hid_warn(pidff->hid, "unknown constant effect layout\n");
  clear_bit(FF_CONSTANT, dev->ffbit);
 }

 if (test_bit(FF_RAMP, dev->ffbit) &&
     PIDFF_FIND_FIELDS(set_ramp, PID_SET_RAMP, 1)) {
  hid_warn(pidff->hid, "unknown ramp effect layout\n");
  clear_bit(FF_RAMP, dev->ffbit);
 }

 if (test_bit(FF_SPRING, dev->ffbit) ||
     test_bit(FF_DAMPER, dev->ffbit) ||
     test_bit(FF_FRICTION, dev->ffbit) ||
     test_bit(FF_INERTIA, dev->ffbit)) {
  status = PIDFF_FIND_FIELDS(set_condition, PID_SET_CONDITION, 1);

  if (status < 0) {
   hid_warn(pidff->hid, "unknown condition effect layout\n");
   clear_bit(FF_SPRING, dev->ffbit);
   clear_bit(FF_DAMPER, dev->ffbit);
   clear_bit(FF_FRICTION, dev->ffbit);
   clear_bit(FF_INERTIA, dev->ffbit);
  }
  pidff->quirks |= status;
 }

 if (test_bit(FF_PERIODIC, dev->ffbit) &&
     PIDFF_FIND_FIELDS(set_periodic, PID_SET_PERIODIC, 1)) {
  hid_warn(pidff->hid, "unknown periodic effect layout\n");
  clear_bit(FF_PERIODIC, dev->ffbit);
 }

 PIDFF_FIND_FIELDS(pool, PID_POOL, 0);

 if (!PIDFF_FIND_FIELDS(device_gain, PID_DEVICE_GAIN, 1))
  set_bit(FF_GAIN, dev->ffbit);

 return 0;
}

/*
 * Test if autocenter modification is using the supported method
 */
static int pidff_check_autocenter(struct pidff_device *pidff,
      struct input_dev *dev)
{
 int error;

 /*
 * Let's find out if autocenter modification is supported
 * Specification doesn't specify anything, so we request an
 * effect upload and cancel it immediately. If the approved
 * effect id was one above the minimum, then we assume the first
 * effect id is a built-in spring type effect used for autocenter
 */

 error = pidff_request_effect_upload(pidff, 1);
 if (error) {
  hid_err(pidff->hid, "upload request failed\n");
  return error;
 }

 if (pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] ==
     pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum + 1) {
  pidff_autocenter(pidff, U16_MAX);
  set_bit(FF_AUTOCENTER, dev->ffbit);
 } else {
  hid_notice(pidff->hid,
      "device has unknown autocenter control method\n");
 }
 pidff_erase_pid(pidff,
   pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0]);

 return 0;
}

/*
 * Check if the device is PID and initialize it
 * Set initial quirks
 */
int hid_pidff_init_with_quirks(struct hid_device *hid, u32 initial_quirks)
{
 struct pidff_device *pidff;
 struct hid_input *hidinput = list_entry(hid->inputs.next,
      struct hid_input, list);
 struct input_dev *dev = hidinput->input;
 struct ff_device *ff;
 int max_effects;
 int error;

 hid_dbg(hid, "starting pid init\n");

 if (list_empty(&hid->report_enum[HID_OUTPUT_REPORT].report_list)) {
  hid_dbg(hid, "not a PID device, no output report\n");
  return -ENODEV;
 }

 pidff = kzalloc(sizeof(*pidff), GFP_KERNEL);
 if (!pidff)
  return -ENOMEM;

 pidff->hid = hid;
 pidff->quirks = initial_quirks;
 pidff->effect_count = 0;

 hid_device_io_start(hid);

 pidff_find_reports(hid, HID_OUTPUT_REPORT, pidff);
 pidff_find_reports(hid, HID_FEATURE_REPORT, pidff);

 if (!pidff_reports_ok(pidff)) {
  hid_dbg(hid, "reports not ok, aborting\n");
  error = -ENODEV;
  goto fail;
 }

 error = pidff_init_fields(pidff, dev);
 if (error)
  goto fail;

 /* pool report is sometimes messed up, refetch it */
 pidff_fetch_pool(pidff);
 pidff_set_gain_report(pidff, U16_MAX);
 error = pidff_check_autocenter(pidff, dev);
 if (error)
  goto fail;

 max_effects =
     pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_maximum -
     pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum +
     1;
 hid_dbg(hid, "max effects is %d\n", max_effects);

 if (max_effects > PID_EFFECTS_MAX)
  max_effects = PID_EFFECTS_MAX;

 if (pidff->pool[PID_SIMULTANEOUS_MAX].value)
  hid_dbg(hid, "max simultaneous effects is %d\n",
   pidff->pool[PID_SIMULTANEOUS_MAX].value[0]);

 if (pidff->pool[PID_RAM_POOL_SIZE].value)
  hid_dbg(hid, "device memory size is %d bytes\n",
   pidff->pool[PID_RAM_POOL_SIZE].value[0]);

 if (pidff->pool[PID_DEVICE_MANAGED_POOL].value &&
     pidff->pool[PID_DEVICE_MANAGED_POOL].value[0] == 0) {
  error = -EPERM;
  hid_notice(hid,
      "device does not support device managed pool\n");
  goto fail;
 }

 error = input_ff_create(dev, max_effects);
 if (error)
  goto fail;

 ff = dev->ff;
 ff->private = pidff;
 ff->upload = pidff_upload_effect;
 ff->erase = pidff_erase_effect;
 ff->set_gain = pidff_set_gain;
 ff->set_autocenter = pidff_set_autocenter;
 ff->playback = pidff_playback;

 hid_info(dev, "Force feedback for USB HID PID devices by Anssi Hannula \n");
 hid_dbg(dev, "Active quirks mask: 0x%08x\n", pidff->quirks);

 hid_device_io_stop(hid);

 return 0;

 fail:
 hid_device_io_stop(hid);

 kfree(pidff);
 return error;
}
EXPORT_SYMBOL_GPL(hid_pidff_init_with_quirks);

/*
 * Check if the device is PID and initialize it
 * Wrapper made to keep the compatibility with old
 * init function
 */
int hid_pidff_init(struct hid_device *hid)
{
 return hid_pidff_init_with_quirks(hid, 0);
}