Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / hid / hid-lg4ff.c
diff --git a/kernel/drivers/hid/hid-lg4ff.c b/kernel/drivers/hid/hid-lg4ff.c
new file mode 100644 (file)
index 0000000..1232210
--- /dev/null
@@ -0,0 +1,1211 @@
+/*
+ *  Force feedback support for Logitech Gaming Wheels
+ *
+ *  Including G27, G25, DFP, DFGT, FFEX, Momo, Momo2 &
+ *  Speed Force Wireless (WiiWheel)
+ *
+ *  Copyright (c) 2010 Simon Wood <simon@mungewell.org>
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+
+#include <linux/input.h>
+#include <linux/usb.h>
+#include <linux/hid.h>
+
+#include "usbhid/usbhid.h"
+#include "hid-lg.h"
+#include "hid-lg4ff.h"
+#include "hid-ids.h"
+
+#define to_hid_device(pdev) container_of(pdev, struct hid_device, dev)
+
+#define LG4FF_MMODE_IS_MULTIMODE 0
+#define LG4FF_MMODE_SWITCHED 1
+#define LG4FF_MMODE_NOT_MULTIMODE 2
+
+#define LG4FF_MODE_NATIVE_IDX 0
+#define LG4FF_MODE_DFEX_IDX 1
+#define LG4FF_MODE_DFP_IDX 2
+#define LG4FF_MODE_G25_IDX 3
+#define LG4FF_MODE_DFGT_IDX 4
+#define LG4FF_MODE_G27_IDX 5
+#define LG4FF_MODE_MAX_IDX 6
+
+#define LG4FF_MODE_NATIVE BIT(LG4FF_MODE_NATIVE_IDX)
+#define LG4FF_MODE_DFEX BIT(LG4FF_MODE_DFEX_IDX)
+#define LG4FF_MODE_DFP BIT(LG4FF_MODE_DFP_IDX)
+#define LG4FF_MODE_G25 BIT(LG4FF_MODE_G25_IDX)
+#define LG4FF_MODE_DFGT BIT(LG4FF_MODE_DFGT_IDX)
+#define LG4FF_MODE_G27 BIT(LG4FF_MODE_G27_IDX)
+
+#define LG4FF_DFEX_TAG "DF-EX"
+#define LG4FF_DFEX_NAME "Driving Force / Formula EX"
+#define LG4FF_DFP_TAG "DFP"
+#define LG4FF_DFP_NAME "Driving Force Pro"
+#define LG4FF_G25_TAG "G25"
+#define LG4FF_G25_NAME "G25 Racing Wheel"
+#define LG4FF_G27_TAG "G27"
+#define LG4FF_G27_NAME "G27 Racing Wheel"
+#define LG4FF_DFGT_TAG "DFGT"
+#define LG4FF_DFGT_NAME "Driving Force GT"
+
+#define LG4FF_FFEX_REV_MAJ 0x21
+#define LG4FF_FFEX_REV_MIN 0x00
+
+static void hid_lg4ff_set_range_dfp(struct hid_device *hid, u16 range);
+static void hid_lg4ff_set_range_g25(struct hid_device *hid, u16 range);
+
+struct lg4ff_device_entry {
+       __u32 product_id;
+       __u16 range;
+       __u16 min_range;
+       __u16 max_range;
+#ifdef CONFIG_LEDS_CLASS
+       __u8  led_state;
+       struct led_classdev *led[5];
+#endif
+       u32 alternate_modes;
+       const char *real_tag;
+       const char *real_name;
+       u16 real_product_id;
+       struct list_head list;
+       void (*set_range)(struct hid_device *hid, u16 range);
+};
+
+static const signed short lg4ff_wheel_effects[] = {
+       FF_CONSTANT,
+       FF_AUTOCENTER,
+       -1
+};
+
+struct lg4ff_wheel {
+       const __u32 product_id;
+       const signed short *ff_effects;
+       const __u16 min_range;
+       const __u16 max_range;
+       void (*set_range)(struct hid_device *hid, u16 range);
+};
+
+struct lg4ff_compat_mode_switch {
+       const __u8 cmd_count;   /* Number of commands to send */
+       const __u8 cmd[];
+};
+
+struct lg4ff_wheel_ident_info {
+       const u16 mask;
+       const u16 result;
+       const u16 real_product_id;
+};
+
+struct lg4ff_wheel_ident_checklist {
+       const u32 count;
+       const struct lg4ff_wheel_ident_info *models[];
+};
+
+struct lg4ff_multimode_wheel {
+       const u16 product_id;
+       const u32 alternate_modes;
+       const char *real_tag;
+       const char *real_name;
+};
+
+struct lg4ff_alternate_mode {
+       const u16 product_id;
+       const char *tag;
+       const char *name;
+};
+
+static const struct lg4ff_wheel lg4ff_devices[] = {
+       {USB_DEVICE_ID_LOGITECH_WHEEL,       lg4ff_wheel_effects, 40, 270, NULL},
+       {USB_DEVICE_ID_LOGITECH_MOMO_WHEEL,  lg4ff_wheel_effects, 40, 270, NULL},
+       {USB_DEVICE_ID_LOGITECH_DFP_WHEEL,   lg4ff_wheel_effects, 40, 900, hid_lg4ff_set_range_dfp},
+       {USB_DEVICE_ID_LOGITECH_G25_WHEEL,   lg4ff_wheel_effects, 40, 900, hid_lg4ff_set_range_g25},
+       {USB_DEVICE_ID_LOGITECH_DFGT_WHEEL,  lg4ff_wheel_effects, 40, 900, hid_lg4ff_set_range_g25},
+       {USB_DEVICE_ID_LOGITECH_G27_WHEEL,   lg4ff_wheel_effects, 40, 900, hid_lg4ff_set_range_g25},
+       {USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2, lg4ff_wheel_effects, 40, 270, NULL},
+       {USB_DEVICE_ID_LOGITECH_WII_WHEEL,   lg4ff_wheel_effects, 40, 270, NULL}
+};
+
+static const struct lg4ff_multimode_wheel lg4ff_multimode_wheels[] = {
+       {USB_DEVICE_ID_LOGITECH_DFP_WHEEL,
+        LG4FF_MODE_NATIVE | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
+        LG4FF_DFP_TAG, LG4FF_DFP_NAME},
+       {USB_DEVICE_ID_LOGITECH_G25_WHEEL,
+        LG4FF_MODE_NATIVE | LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
+        LG4FF_G25_TAG, LG4FF_G25_NAME},
+       {USB_DEVICE_ID_LOGITECH_DFGT_WHEEL,
+        LG4FF_MODE_NATIVE | LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
+        LG4FF_DFGT_TAG, LG4FF_DFGT_NAME},
+       {USB_DEVICE_ID_LOGITECH_G27_WHEEL,
+        LG4FF_MODE_NATIVE | LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
+        LG4FF_G27_TAG, LG4FF_G27_NAME},
+};
+
+static const struct lg4ff_alternate_mode lg4ff_alternate_modes[] = {
+       [LG4FF_MODE_NATIVE_IDX] = {0, "native", ""},
+       [LG4FF_MODE_DFEX_IDX] = {USB_DEVICE_ID_LOGITECH_WHEEL, LG4FF_DFEX_TAG, LG4FF_DFEX_NAME},
+       [LG4FF_MODE_DFP_IDX] = {USB_DEVICE_ID_LOGITECH_DFP_WHEEL, LG4FF_DFP_TAG, LG4FF_DFP_NAME},
+       [LG4FF_MODE_G25_IDX] = {USB_DEVICE_ID_LOGITECH_G25_WHEEL, LG4FF_G25_TAG, LG4FF_G25_NAME},
+       [LG4FF_MODE_DFGT_IDX] = {USB_DEVICE_ID_LOGITECH_DFGT_WHEEL, LG4FF_DFGT_TAG, LG4FF_DFGT_NAME},
+       [LG4FF_MODE_G27_IDX] = {USB_DEVICE_ID_LOGITECH_G27_WHEEL, LG4FF_G27_TAG, LG4FF_G27_NAME}
+};
+
+/* Multimode wheel identificators */
+static const struct lg4ff_wheel_ident_info lg4ff_dfp_ident_info = {
+       0xf000,
+       0x1000,
+       USB_DEVICE_ID_LOGITECH_DFP_WHEEL
+};
+
+static const struct lg4ff_wheel_ident_info lg4ff_g25_ident_info = {
+       0xff00,
+       0x1200,
+       USB_DEVICE_ID_LOGITECH_G25_WHEEL
+};
+
+static const struct lg4ff_wheel_ident_info lg4ff_g27_ident_info = {
+       0xfff0,
+       0x1230,
+       USB_DEVICE_ID_LOGITECH_G27_WHEEL
+};
+
+static const struct lg4ff_wheel_ident_info lg4ff_dfgt_ident_info = {
+       0xff00,
+       0x1300,
+       USB_DEVICE_ID_LOGITECH_DFGT_WHEEL
+};
+
+/* Multimode wheel identification checklists */
+static const struct lg4ff_wheel_ident_checklist lg4ff_main_checklist = {
+       4,
+       {&lg4ff_dfgt_ident_info,
+        &lg4ff_g27_ident_info,
+        &lg4ff_g25_ident_info,
+        &lg4ff_dfp_ident_info}
+};
+
+/* Compatibility mode switching commands */
+/* EXT_CMD9 - Understood by G27 and DFGT */
+static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_dfex = {
+       2,
+       {0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,      /* Revert mode upon USB reset */
+        0xf8, 0x09, 0x00, 0x01, 0x00, 0x00, 0x00}      /* Switch mode to DF-EX with detach */
+};
+
+static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_dfp = {
+       2,
+       {0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,      /* Revert mode upon USB reset */
+        0xf8, 0x09, 0x01, 0x01, 0x00, 0x00, 0x00}      /* Switch mode to DFP with detach */
+};
+
+static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_g25 = {
+       2,
+       {0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,      /* Revert mode upon USB reset */
+        0xf8, 0x09, 0x02, 0x01, 0x00, 0x00, 0x00}      /* Switch mode to G25 with detach */
+};
+
+static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_dfgt = {
+       2,
+       {0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,      /* Revert mode upon USB reset */
+        0xf8, 0x09, 0x03, 0x01, 0x00, 0x00, 0x00}      /* Switch mode to DFGT with detach */
+};
+
+static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_g27 = {
+       2,
+       {0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,      /* Revert mode upon USB reset */
+        0xf8, 0x09, 0x04, 0x01, 0x00, 0x00, 0x00}      /* Switch mode to G27 with detach */
+};
+
+/* EXT_CMD1 - Understood by DFP, G25, G27 and DFGT */
+static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext01_dfp = {
+       1,
+       {0xf8, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00}
+};
+
+/* EXT_CMD16 - Understood by G25 and G27 */
+static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext16_g25 = {
+       1,
+       {0xf8, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00}
+};
+
+/* Recalculates X axis value accordingly to currently selected range */
+static __s32 lg4ff_adjust_dfp_x_axis(__s32 value, __u16 range)
+{
+       __u16 max_range;
+       __s32 new_value;
+
+       if (range == 900)
+               return value;
+       else if (range == 200)
+               return value;
+       else if (range < 200)
+               max_range = 200;
+       else
+               max_range = 900;
+
+       new_value = 8192 + mult_frac(value - 8192, max_range, range);
+       if (new_value < 0)
+               return 0;
+       else if (new_value > 16383)
+               return 16383;
+       else
+               return new_value;
+}
+
+int lg4ff_adjust_input_event(struct hid_device *hid, struct hid_field *field,
+                            struct hid_usage *usage, __s32 value, struct lg_drv_data *drv_data)
+{
+       struct lg4ff_device_entry *entry = drv_data->device_props;
+       __s32 new_value = 0;
+
+       if (!entry) {
+               hid_err(hid, "Device properties not found");
+               return 0;
+       }
+
+       switch (entry->product_id) {
+       case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
+               switch (usage->code) {
+               case ABS_X:
+                       new_value = lg4ff_adjust_dfp_x_axis(value, entry->range);
+                       input_event(field->hidinput->input, usage->type, usage->code, new_value);
+                       return 1;
+               default:
+                       return 0;
+               }
+       default:
+               return 0;
+       }
+}
+
+static int hid_lg4ff_play(struct input_dev *dev, void *data, struct ff_effect *effect)
+{
+       struct hid_device *hid = input_get_drvdata(dev);
+       struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+       struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+       __s32 *value = report->field[0]->value;
+       int x;
+
+#define CLAMP(x) do { if (x < 0) x = 0; else if (x > 0xff) x = 0xff; } while (0)
+
+       switch (effect->type) {
+       case FF_CONSTANT:
+               x = effect->u.ramp.start_level + 0x80;  /* 0x80 is no force */
+               CLAMP(x);
+
+               if (x == 0x80) {
+                       /* De-activate force in slot-1*/
+                       value[0] = 0x13;
+                       value[1] = 0x00;
+                       value[2] = 0x00;
+                       value[3] = 0x00;
+                       value[4] = 0x00;
+                       value[5] = 0x00;
+                       value[6] = 0x00;
+
+                       hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+                       return 0;
+               }
+
+               value[0] = 0x11;        /* Slot 1 */
+               value[1] = 0x08;
+               value[2] = x;
+               value[3] = 0x80;
+               value[4] = 0x00;
+               value[5] = 0x00;
+               value[6] = 0x00;
+
+               hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+               break;
+       }
+       return 0;
+}
+
+/* Sends default autocentering command compatible with
+ * all wheels except Formula Force EX */
+static void hid_lg4ff_set_autocenter_default(struct input_dev *dev, u16 magnitude)
+{
+       struct hid_device *hid = input_get_drvdata(dev);
+       struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+       struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+       __s32 *value = report->field[0]->value;
+       __u32 expand_a, expand_b;
+       struct lg4ff_device_entry *entry;
+       struct lg_drv_data *drv_data;
+
+       drv_data = hid_get_drvdata(hid);
+       if (!drv_data) {
+               hid_err(hid, "Private driver data not found!\n");
+               return;
+       }
+
+       entry = drv_data->device_props;
+       if (!entry) {
+               hid_err(hid, "Device properties not found!\n");
+               return;
+       }
+
+       /* De-activate Auto-Center */
+       if (magnitude == 0) {
+               value[0] = 0xf5;
+               value[1] = 0x00;
+               value[2] = 0x00;
+               value[3] = 0x00;
+               value[4] = 0x00;
+               value[5] = 0x00;
+               value[6] = 0x00;
+
+               hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+               return;
+       }
+
+       if (magnitude <= 0xaaaa) {
+               expand_a = 0x0c * magnitude;
+               expand_b = 0x80 * magnitude;
+       } else {
+               expand_a = (0x0c * 0xaaaa) + 0x06 * (magnitude - 0xaaaa);
+               expand_b = (0x80 * 0xaaaa) + 0xff * (magnitude - 0xaaaa);
+       }
+
+       /* Adjust for non-MOMO wheels */
+       switch (entry->product_id) {
+       case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL:
+       case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2:
+               break;
+       default:
+               expand_a = expand_a >> 1;
+               break;
+       }
+
+       value[0] = 0xfe;
+       value[1] = 0x0d;
+       value[2] = expand_a / 0xaaaa;
+       value[3] = expand_a / 0xaaaa;
+       value[4] = expand_b / 0xaaaa;
+       value[5] = 0x00;
+       value[6] = 0x00;
+
+       hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+
+       /* Activate Auto-Center */
+       value[0] = 0x14;
+       value[1] = 0x00;
+       value[2] = 0x00;
+       value[3] = 0x00;
+       value[4] = 0x00;
+       value[5] = 0x00;
+       value[6] = 0x00;
+
+       hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+}
+
+/* Sends autocentering command compatible with Formula Force EX */
+static void hid_lg4ff_set_autocenter_ffex(struct input_dev *dev, u16 magnitude)
+{
+       struct hid_device *hid = input_get_drvdata(dev);
+       struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+       struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+       __s32 *value = report->field[0]->value;
+       magnitude = magnitude * 90 / 65535;
+
+       value[0] = 0xfe;
+       value[1] = 0x03;
+       value[2] = magnitude >> 14;
+       value[3] = magnitude >> 14;
+       value[4] = magnitude;
+       value[5] = 0x00;
+       value[6] = 0x00;
+
+       hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+}
+
+/* Sends command to set range compatible with G25/G27/Driving Force GT */
+static void hid_lg4ff_set_range_g25(struct hid_device *hid, u16 range)
+{
+       struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+       struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+       __s32 *value = report->field[0]->value;
+
+       dbg_hid("G25/G27/DFGT: setting range to %u\n", range);
+
+       value[0] = 0xf8;
+       value[1] = 0x81;
+       value[2] = range & 0x00ff;
+       value[3] = (range & 0xff00) >> 8;
+       value[4] = 0x00;
+       value[5] = 0x00;
+       value[6] = 0x00;
+
+       hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+}
+
+/* Sends commands to set range compatible with Driving Force Pro wheel */
+static void hid_lg4ff_set_range_dfp(struct hid_device *hid, __u16 range)
+{
+       struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+       struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+       int start_left, start_right, full_range;
+       __s32 *value = report->field[0]->value;
+
+       dbg_hid("Driving Force Pro: setting range to %u\n", range);
+
+       /* Prepare "coarse" limit command */
+       value[0] = 0xf8;
+       value[1] = 0x00;        /* Set later */
+       value[2] = 0x00;
+       value[3] = 0x00;
+       value[4] = 0x00;
+       value[5] = 0x00;
+       value[6] = 0x00;
+
+       if (range > 200) {
+               report->field[0]->value[1] = 0x03;
+               full_range = 900;
+       } else {
+               report->field[0]->value[1] = 0x02;
+               full_range = 200;
+       }
+       hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+
+       /* Prepare "fine" limit command */
+       value[0] = 0x81;
+       value[1] = 0x0b;
+       value[2] = 0x00;
+       value[3] = 0x00;
+       value[4] = 0x00;
+       value[5] = 0x00;
+       value[6] = 0x00;
+
+       if (range == 200 || range == 900) {     /* Do not apply any fine limit */
+               hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+               return;
+       }
+
+       /* Construct fine limit command */
+       start_left = (((full_range - range + 1) * 2047) / full_range);
+       start_right = 0xfff - start_left;
+
+       value[2] = start_left >> 4;
+       value[3] = start_right >> 4;
+       value[4] = 0xff;
+       value[5] = (start_right & 0xe) << 4 | (start_left & 0xe);
+       value[6] = 0xff;
+
+       hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+}
+
+static const struct lg4ff_compat_mode_switch *lg4ff_get_mode_switch_command(const u16 real_product_id, const u16 target_product_id)
+{
+       switch (real_product_id) {
+       case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
+               switch (target_product_id) {
+               case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
+                       return &lg4ff_mode_switch_ext01_dfp;
+               /* DFP can only be switched to its native mode */
+               default:
+                       return NULL;
+               }
+               break;
+       case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
+               switch (target_product_id) {
+               case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
+                       return &lg4ff_mode_switch_ext01_dfp;
+               case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
+                       return &lg4ff_mode_switch_ext16_g25;
+               /* G25 can only be switched to DFP mode or its native mode */
+               default:
+                       return NULL;
+               }
+               break;
+       case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
+               switch (target_product_id) {
+               case USB_DEVICE_ID_LOGITECH_WHEEL:
+                       return &lg4ff_mode_switch_ext09_dfex;
+               case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
+                       return &lg4ff_mode_switch_ext09_dfp;
+               case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
+                       return &lg4ff_mode_switch_ext09_g25;
+               case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
+                       return &lg4ff_mode_switch_ext09_g27;
+               /* G27 can only be switched to DF-EX, DFP, G25 or its native mode */
+               default:
+                       return NULL;
+               }
+               break;
+       case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
+               switch (target_product_id) {
+               case USB_DEVICE_ID_LOGITECH_WHEEL:
+                       return &lg4ff_mode_switch_ext09_dfex;
+               case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
+                       return &lg4ff_mode_switch_ext09_dfp;
+               case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
+                       return &lg4ff_mode_switch_ext09_dfgt;
+               /* DFGT can only be switched to DF-EX, DFP or its native mode */
+               default:
+                       return NULL;
+               }
+               break;
+       /* No other wheels have multiple modes */
+       default:
+               return NULL;
+       }
+}
+
+static int lg4ff_switch_compatibility_mode(struct hid_device *hid, const struct lg4ff_compat_mode_switch *s)
+{
+       struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+       struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+       __s32 *value = report->field[0]->value;
+       u8 i;
+
+       for (i = 0; i < s->cmd_count; i++) {
+               u8 j;
+
+               for (j = 0; j < 7; j++)
+                       value[j] = s->cmd[j + (7*i)];
+
+               hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+       }
+       hid_hw_wait(hid);
+       return 0;
+}
+
+static ssize_t lg4ff_alternate_modes_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct hid_device *hid = to_hid_device(dev);
+       struct lg4ff_device_entry *entry;
+       struct lg_drv_data *drv_data;
+       ssize_t count = 0;
+       int i;
+
+       drv_data = hid_get_drvdata(hid);
+       if (!drv_data) {
+               hid_err(hid, "Private driver data not found!\n");
+               return 0;
+       }
+
+       entry = drv_data->device_props;
+       if (!entry) {
+               hid_err(hid, "Device properties not found!\n");
+               return 0;
+       }
+
+       if (!entry->real_name) {
+               hid_err(hid, "NULL pointer to string\n");
+               return 0;
+       }
+
+       for (i = 0; i < LG4FF_MODE_MAX_IDX; i++) {
+               if (entry->alternate_modes & BIT(i)) {
+                       /* Print tag and full name */
+                       count += scnprintf(buf + count, PAGE_SIZE - count, "%s: %s",
+                                          lg4ff_alternate_modes[i].tag,
+                                          !lg4ff_alternate_modes[i].product_id ? entry->real_name : lg4ff_alternate_modes[i].name);
+                       if (count >= PAGE_SIZE - 1)
+                               return count;
+
+                       /* Mark the currently active mode with an asterisk */
+                       if (lg4ff_alternate_modes[i].product_id == entry->product_id ||
+                           (lg4ff_alternate_modes[i].product_id == 0 && entry->product_id == entry->real_product_id))
+                               count += scnprintf(buf + count, PAGE_SIZE - count, " *\n");
+                       else
+                               count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
+
+                       if (count >= PAGE_SIZE - 1)
+                               return count;
+               }
+       }
+
+       return count;
+}
+
+static ssize_t lg4ff_alternate_modes_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
+{
+       struct hid_device *hid = to_hid_device(dev);
+       struct lg4ff_device_entry *entry;
+       struct lg_drv_data *drv_data;
+       const struct lg4ff_compat_mode_switch *s;
+       u16 target_product_id = 0;
+       int i, ret;
+       char *lbuf;
+
+       drv_data = hid_get_drvdata(hid);
+       if (!drv_data) {
+               hid_err(hid, "Private driver data not found!\n");
+               return -EINVAL;
+       }
+
+       entry = drv_data->device_props;
+       if (!entry) {
+               hid_err(hid, "Device properties not found!\n");
+               return -EINVAL;
+       }
+
+       /* Allow \n at the end of the input parameter */
+       lbuf = kasprintf(GFP_KERNEL, "%s", buf);
+       if (!lbuf)
+               return -ENOMEM;
+
+       i = strlen(lbuf);
+       if (lbuf[i-1] == '\n') {
+               if (i == 1) {
+                       kfree(lbuf);
+                       return -EINVAL;
+               }
+               lbuf[i-1] = '\0';
+       }
+
+       for (i = 0; i < LG4FF_MODE_MAX_IDX; i++) {
+               const u16 mode_product_id = lg4ff_alternate_modes[i].product_id;
+               const char *tag = lg4ff_alternate_modes[i].tag;
+
+               if (entry->alternate_modes & BIT(i)) {
+                       if (!strcmp(tag, lbuf)) {
+                               if (!mode_product_id)
+                                       target_product_id = entry->real_product_id;
+                               else
+                                       target_product_id = mode_product_id;
+                               break;
+                       }
+               }
+       }
+
+       if (i == LG4FF_MODE_MAX_IDX) {
+               hid_info(hid, "Requested mode \"%s\" is not supported by the device\n", lbuf);
+               kfree(lbuf);
+               return -EINVAL;
+       }
+       kfree(lbuf); /* Not needed anymore */
+
+       if (target_product_id == entry->product_id) /* Nothing to do */
+               return count;
+
+       /* Automatic switching has to be disabled for the switch to DF-EX mode to work correctly */
+       if (target_product_id == USB_DEVICE_ID_LOGITECH_WHEEL && !lg4ff_no_autoswitch) {
+               hid_info(hid, "\"%s\" cannot be switched to \"DF-EX\" mode. Load the \"hid_logitech\" module with \"lg4ff_no_autoswitch=1\" parameter set and try again\n",
+                        entry->real_name);
+               return -EINVAL;
+       }
+
+       /* Take care of hardware limitations */
+       if ((entry->real_product_id == USB_DEVICE_ID_LOGITECH_DFP_WHEEL || entry->real_product_id == USB_DEVICE_ID_LOGITECH_G25_WHEEL) &&
+           entry->product_id > target_product_id) {
+               hid_info(hid, "\"%s\" cannot be switched back into \"%s\" mode\n", entry->real_name, lg4ff_alternate_modes[i].name);
+               return -EINVAL;
+       }
+
+       s = lg4ff_get_mode_switch_command(entry->real_product_id, target_product_id);
+       if (!s) {
+               hid_err(hid, "Invalid target product ID %X\n", target_product_id);
+               return -EINVAL;
+       }
+
+       ret = lg4ff_switch_compatibility_mode(hid, s);
+       return (ret == 0 ? count : ret);
+}
+static DEVICE_ATTR(alternate_modes, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH, lg4ff_alternate_modes_show, lg4ff_alternate_modes_store);
+
+/* Read current range and display it in terminal */
+static ssize_t range_show(struct device *dev, struct device_attribute *attr,
+                         char *buf)
+{
+       struct hid_device *hid = to_hid_device(dev);
+       struct lg4ff_device_entry *entry;
+       struct lg_drv_data *drv_data;
+       size_t count;
+
+       drv_data = hid_get_drvdata(hid);
+       if (!drv_data) {
+               hid_err(hid, "Private driver data not found!\n");
+               return 0;
+       }
+
+       entry = drv_data->device_props;
+       if (!entry) {
+               hid_err(hid, "Device properties not found!\n");
+               return 0;
+       }
+
+       count = scnprintf(buf, PAGE_SIZE, "%u\n", entry->range);
+       return count;
+}
+
+/* Set range to user specified value, call appropriate function
+ * according to the type of the wheel */
+static ssize_t range_store(struct device *dev, struct device_attribute *attr,
+                          const char *buf, size_t count)
+{
+       struct hid_device *hid = to_hid_device(dev);
+       struct lg4ff_device_entry *entry;
+       struct lg_drv_data *drv_data;
+       __u16 range = simple_strtoul(buf, NULL, 10);
+
+       drv_data = hid_get_drvdata(hid);
+       if (!drv_data) {
+               hid_err(hid, "Private driver data not found!\n");
+               return -EINVAL;
+       }
+
+       entry = drv_data->device_props;
+       if (!entry) {
+               hid_err(hid, "Device properties not found!\n");
+               return -EINVAL;
+       }
+
+       if (range == 0)
+               range = entry->max_range;
+
+       /* Check if the wheel supports range setting
+        * and that the range is within limits for the wheel */
+       if (entry->set_range != NULL && range >= entry->min_range && range <= entry->max_range) {
+               entry->set_range(hid, range);
+               entry->range = range;
+       }
+
+       return count;
+}
+static DEVICE_ATTR_RW(range);
+
+static ssize_t lg4ff_real_id_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct hid_device *hid = to_hid_device(dev);
+       struct lg4ff_device_entry *entry;
+       struct lg_drv_data *drv_data;
+       size_t count;
+
+       drv_data = hid_get_drvdata(hid);
+       if (!drv_data) {
+               hid_err(hid, "Private driver data not found!\n");
+               return 0;
+       }
+
+       entry = drv_data->device_props;
+       if (!entry) {
+               hid_err(hid, "Device properties not found!\n");
+               return 0;
+       }
+
+       if (!entry->real_tag || !entry->real_name) {
+               hid_err(hid, "NULL pointer to string\n");
+               return 0;
+       }
+
+       count = scnprintf(buf, PAGE_SIZE, "%s: %s\n", entry->real_tag, entry->real_name);
+       return count;
+}
+
+static ssize_t lg4ff_real_id_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
+{
+       /* Real ID is a read-only value */
+       return -EPERM;
+}
+static DEVICE_ATTR(real_id, S_IRUGO, lg4ff_real_id_show, lg4ff_real_id_store);
+
+#ifdef CONFIG_LEDS_CLASS
+static void lg4ff_set_leds(struct hid_device *hid, __u8 leds)
+{
+       struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+       struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
+       __s32 *value = report->field[0]->value;
+
+       value[0] = 0xf8;
+       value[1] = 0x12;
+       value[2] = leds;
+       value[3] = 0x00;
+       value[4] = 0x00;
+       value[5] = 0x00;
+       value[6] = 0x00;
+       hid_hw_request(hid, report, HID_REQ_SET_REPORT);
+}
+
+static void lg4ff_led_set_brightness(struct led_classdev *led_cdev,
+                       enum led_brightness value)
+{
+       struct device *dev = led_cdev->dev->parent;
+       struct hid_device *hid = container_of(dev, struct hid_device, dev);
+       struct lg_drv_data *drv_data = hid_get_drvdata(hid);
+       struct lg4ff_device_entry *entry;
+       int i, state = 0;
+
+       if (!drv_data) {
+               hid_err(hid, "Device data not found.");
+               return;
+       }
+
+       entry = (struct lg4ff_device_entry *)drv_data->device_props;
+
+       if (!entry) {
+               hid_err(hid, "Device properties not found.");
+               return;
+       }
+
+       for (i = 0; i < 5; i++) {
+               if (led_cdev != entry->led[i])
+                       continue;
+               state = (entry->led_state >> i) & 1;
+               if (value == LED_OFF && state) {
+                       entry->led_state &= ~(1 << i);
+                       lg4ff_set_leds(hid, entry->led_state);
+               } else if (value != LED_OFF && !state) {
+                       entry->led_state |= 1 << i;
+                       lg4ff_set_leds(hid, entry->led_state);
+               }
+               break;
+       }
+}
+
+static enum led_brightness lg4ff_led_get_brightness(struct led_classdev *led_cdev)
+{
+       struct device *dev = led_cdev->dev->parent;
+       struct hid_device *hid = container_of(dev, struct hid_device, dev);
+       struct lg_drv_data *drv_data = hid_get_drvdata(hid);
+       struct lg4ff_device_entry *entry;
+       int i, value = 0;
+
+       if (!drv_data) {
+               hid_err(hid, "Device data not found.");
+               return LED_OFF;
+       }
+
+       entry = (struct lg4ff_device_entry *)drv_data->device_props;
+
+       if (!entry) {
+               hid_err(hid, "Device properties not found.");
+               return LED_OFF;
+       }
+
+       for (i = 0; i < 5; i++)
+               if (led_cdev == entry->led[i]) {
+                       value = (entry->led_state >> i) & 1;
+                       break;
+               }
+
+       return value ? LED_FULL : LED_OFF;
+}
+#endif
+
+static u16 lg4ff_identify_multimode_wheel(struct hid_device *hid, const u16 reported_product_id, const u16 bcdDevice)
+{
+       const struct lg4ff_wheel_ident_checklist *checklist;
+       int i, from_idx, to_idx;
+
+       switch (reported_product_id) {
+       case USB_DEVICE_ID_LOGITECH_WHEEL:
+       case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
+               checklist = &lg4ff_main_checklist;
+               from_idx = 0;
+               to_idx = checklist->count - 1;
+               break;
+       case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
+               checklist = &lg4ff_main_checklist;
+               from_idx = 0;
+               to_idx = checklist->count - 2; /* End identity check at G25 */
+               break;
+       case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
+               checklist = &lg4ff_main_checklist;
+               from_idx = 1; /* Start identity check at G27 */
+               to_idx = checklist->count - 3; /* End identity check at G27 */
+               break;
+       case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
+               checklist = &lg4ff_main_checklist;
+               from_idx = 0;
+               to_idx = checklist->count - 4; /* End identity check at DFGT */
+               break;
+       default:
+               return 0;
+       }
+
+       for (i = from_idx; i <= to_idx; i++) {
+               const u16 mask = checklist->models[i]->mask;
+               const u16 result = checklist->models[i]->result;
+               const u16 real_product_id = checklist->models[i]->real_product_id;
+
+               if ((bcdDevice & mask) == result) {
+                       dbg_hid("Found wheel with real PID %X whose reported PID is %X\n", real_product_id, reported_product_id);
+                       return real_product_id;
+               }
+       }
+
+       /* No match found. This is either Driving Force or an unknown
+        * wheel model, do not touch it */
+       dbg_hid("Wheel with bcdDevice %X was not recognized as multimode wheel, leaving in its current mode\n", bcdDevice);
+       return 0;
+}
+
+static int lg4ff_handle_multimode_wheel(struct hid_device *hid, u16 *real_product_id, const u16 bcdDevice)
+{
+       const u16 reported_product_id = hid->product;
+       int ret;
+
+       *real_product_id = lg4ff_identify_multimode_wheel(hid, reported_product_id, bcdDevice);
+       /* Probed wheel is not a multimode wheel */
+       if (!*real_product_id) {
+               *real_product_id = reported_product_id;
+               dbg_hid("Wheel is not a multimode wheel\n");
+               return LG4FF_MMODE_NOT_MULTIMODE;
+       }
+
+       /* Switch from "Driving Force" mode to native mode automatically.
+        * Otherwise keep the wheel in its current mode */
+       if (reported_product_id == USB_DEVICE_ID_LOGITECH_WHEEL &&
+           reported_product_id != *real_product_id &&
+           !lg4ff_no_autoswitch) {
+               const struct lg4ff_compat_mode_switch *s = lg4ff_get_mode_switch_command(*real_product_id, *real_product_id);
+
+               if (!s) {
+                       hid_err(hid, "Invalid product id %X\n", *real_product_id);
+                       return LG4FF_MMODE_NOT_MULTIMODE;
+               }
+
+               ret = lg4ff_switch_compatibility_mode(hid, s);
+               if (ret) {
+                       /* Wheel could not have been switched to native mode,
+                        * leave it in "Driving Force" mode and continue */
+                       hid_err(hid, "Unable to switch wheel mode, errno %d\n", ret);
+                       return LG4FF_MMODE_IS_MULTIMODE;
+               }
+               return LG4FF_MMODE_SWITCHED;
+       }
+
+       return LG4FF_MMODE_IS_MULTIMODE;
+}
+
+
+int lg4ff_init(struct hid_device *hid)
+{
+       struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+       struct input_dev *dev = hidinput->input;
+       const struct usb_device_descriptor *udesc = &(hid_to_usb_dev(hid)->descriptor);
+       const u16 bcdDevice = le16_to_cpu(udesc->bcdDevice);
+       struct lg4ff_device_entry *entry;
+       struct lg_drv_data *drv_data;
+       int error, i, j;
+       int mmode_ret, mmode_idx = -1;
+       u16 real_product_id;
+
+       /* Check that the report looks ok */
+       if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7))
+               return -1;
+
+       /* Check if a multimode wheel has been connected and
+        * handle it appropriately */
+       mmode_ret = lg4ff_handle_multimode_wheel(hid, &real_product_id, bcdDevice);
+
+       /* Wheel has been told to switch to native mode. There is no point in going on
+        * with the initialization as the wheel will do a USB reset when it switches mode
+        */
+       if (mmode_ret == LG4FF_MMODE_SWITCHED)
+               return 0;
+
+       /* Check what wheel has been connected */
+       for (i = 0; i < ARRAY_SIZE(lg4ff_devices); i++) {
+               if (hid->product == lg4ff_devices[i].product_id) {
+                       dbg_hid("Found compatible device, product ID %04X\n", lg4ff_devices[i].product_id);
+                       break;
+               }
+       }
+
+       if (i == ARRAY_SIZE(lg4ff_devices)) {
+               hid_err(hid, "Device is not supported by lg4ff driver. If you think it should be, consider reporting a bug to"
+                            "LKML, Simon Wood <simon@mungewell.org> or Michal Maly <madcatxster@gmail.com>\n");
+               return -1;
+       }
+
+       if (mmode_ret == LG4FF_MMODE_IS_MULTIMODE) {
+               for (mmode_idx = 0; mmode_idx < ARRAY_SIZE(lg4ff_multimode_wheels); mmode_idx++) {
+                       if (real_product_id == lg4ff_multimode_wheels[mmode_idx].product_id)
+                               break;
+               }
+
+               if (mmode_idx == ARRAY_SIZE(lg4ff_multimode_wheels)) {
+                       hid_err(hid, "Device product ID %X is not listed as a multimode wheel", real_product_id);
+                       return -1;
+               }
+       }
+
+       /* Set supported force feedback capabilities */
+       for (j = 0; lg4ff_devices[i].ff_effects[j] >= 0; j++)
+               set_bit(lg4ff_devices[i].ff_effects[j], dev->ffbit);
+
+       error = input_ff_create_memless(dev, NULL, hid_lg4ff_play);
+
+       if (error)
+               return error;
+
+       /* Get private driver data */
+       drv_data = hid_get_drvdata(hid);
+       if (!drv_data) {
+               hid_err(hid, "Cannot add device, private driver data not allocated\n");
+               return -1;
+       }
+
+       /* Initialize device properties */
+       entry = kzalloc(sizeof(struct lg4ff_device_entry), GFP_KERNEL);
+       if (!entry) {
+               hid_err(hid, "Cannot add device, insufficient memory to allocate device properties.\n");
+               return -ENOMEM;
+       }
+       drv_data->device_props = entry;
+
+       entry->product_id = lg4ff_devices[i].product_id;
+       entry->real_product_id = real_product_id;
+       entry->min_range = lg4ff_devices[i].min_range;
+       entry->max_range = lg4ff_devices[i].max_range;
+       entry->set_range = lg4ff_devices[i].set_range;
+       if (mmode_ret == LG4FF_MMODE_IS_MULTIMODE) {
+               BUG_ON(mmode_idx == -1);
+               entry->alternate_modes = lg4ff_multimode_wheels[mmode_idx].alternate_modes;
+               entry->real_tag = lg4ff_multimode_wheels[mmode_idx].real_tag;
+               entry->real_name = lg4ff_multimode_wheels[mmode_idx].real_name;
+       }
+
+       /* Check if autocentering is available and
+        * set the centering force to zero by default */
+       if (test_bit(FF_AUTOCENTER, dev->ffbit)) {
+               /* Formula Force EX expects different autocentering command */
+               if ((bcdDevice >> 8) == LG4FF_FFEX_REV_MAJ &&
+                   (bcdDevice & 0xff) == LG4FF_FFEX_REV_MIN)
+                       dev->ff->set_autocenter = hid_lg4ff_set_autocenter_ffex;
+               else
+                       dev->ff->set_autocenter = hid_lg4ff_set_autocenter_default;
+
+               dev->ff->set_autocenter(dev, 0);
+       }
+
+       /* Create sysfs interface */
+       error = device_create_file(&hid->dev, &dev_attr_range);
+       if (error)
+               return error;
+       if (mmode_ret == LG4FF_MMODE_IS_MULTIMODE) {
+               error = device_create_file(&hid->dev, &dev_attr_real_id);
+               if (error)
+                       return error;
+               error = device_create_file(&hid->dev, &dev_attr_alternate_modes);
+               if (error)
+                       return error;
+       }
+       dbg_hid("sysfs interface created\n");
+
+       /* Set the maximum range to start with */
+       entry->range = entry->max_range;
+       if (entry->set_range != NULL)
+               entry->set_range(hid, entry->range);
+
+#ifdef CONFIG_LEDS_CLASS
+       /* register led subsystem - G27 only */
+       entry->led_state = 0;
+       for (j = 0; j < 5; j++)
+               entry->led[j] = NULL;
+
+       if (lg4ff_devices[i].product_id == USB_DEVICE_ID_LOGITECH_G27_WHEEL) {
+               struct led_classdev *led;
+               size_t name_sz;
+               char *name;
+
+               lg4ff_set_leds(hid, 0);
+
+               name_sz = strlen(dev_name(&hid->dev)) + 8;
+
+               for (j = 0; j < 5; j++) {
+                       led = kzalloc(sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
+                       if (!led) {
+                               hid_err(hid, "can't allocate memory for LED %d\n", j);
+                               goto err;
+                       }
+
+                       name = (void *)(&led[1]);
+                       snprintf(name, name_sz, "%s::RPM%d", dev_name(&hid->dev), j+1);
+                       led->name = name;
+                       led->brightness = 0;
+                       led->max_brightness = 1;
+                       led->brightness_get = lg4ff_led_get_brightness;
+                       led->brightness_set = lg4ff_led_set_brightness;
+
+                       entry->led[j] = led;
+                       error = led_classdev_register(&hid->dev, led);
+
+                       if (error) {
+                               hid_err(hid, "failed to register LED %d. Aborting.\n", j);
+err:
+                               /* Deregister LEDs (if any) */
+                               for (j = 0; j < 5; j++) {
+                                       led = entry->led[j];
+                                       entry->led[j] = NULL;
+                                       if (!led)
+                                               continue;
+                                       led_classdev_unregister(led);
+                                       kfree(led);
+                               }
+                               goto out;       /* Let the driver continue without LEDs */
+                       }
+               }
+       }
+out:
+#endif
+       hid_info(hid, "Force feedback support for Logitech Gaming Wheels\n");
+       return 0;
+}
+
+int lg4ff_deinit(struct hid_device *hid)
+{
+       struct lg4ff_device_entry *entry;
+       struct lg_drv_data *drv_data;
+
+       drv_data = hid_get_drvdata(hid);
+       if (!drv_data) {
+               hid_err(hid, "Error while deinitializing device, no private driver data.\n");
+               return -1;
+       }
+       entry = drv_data->device_props;
+       if (!entry)
+               goto out; /* Nothing more to do */
+
+       device_remove_file(&hid->dev, &dev_attr_range);
+
+       /* Multimode devices will have at least the "MODE_NATIVE" bit set */
+       if (entry->alternate_modes) {
+               device_remove_file(&hid->dev, &dev_attr_real_id);
+               device_remove_file(&hid->dev, &dev_attr_alternate_modes);
+       }
+
+#ifdef CONFIG_LEDS_CLASS
+       {
+               int j;
+               struct led_classdev *led;
+
+               /* Deregister LEDs (if any) */
+               for (j = 0; j < 5; j++) {
+
+                       led = entry->led[j];
+                       entry->led[j] = NULL;
+                       if (!led)
+                               continue;
+                       led_classdev_unregister(led);
+                       kfree(led);
+               }
+       }
+#endif
+
+       /* Deallocate memory */
+       kfree(entry);
+
+out:
+       dbg_hid("Device successfully unregistered\n");
+       return 0;
+}