2 * PID Force feedback support for hid devices.
4 * Copyright (c) 2002 Rodrigo Damazio.
5 * Portions by Johann Deneux and Bjorn Augustson
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 * Should you need to contact me, the author, you can do so by
24 * e-mail - mail your message to <rdamazio@lsi.usp.br>
27 #include <linux/module.h>
28 #include <linux/slab.h>
29 #include <linux/kernel.h>
30 #include <linux/init.h>
32 #include <linux/smp_lock.h>
33 #include <linux/spinlock.h>
34 #include <linux/input.h>
35 #include <linux/usb.h>
39 #define CHECK_OWNERSHIP(i, hid_pid) \
40 ((i) < FF_EFFECTS_MAX && i >= 0 && \
41 test_bit(FF_PID_FLAGS_USED, &hid_pid->effects[(i)].flags) && \
42 (current->pid == 0 || \
43 (hid_pid)->effects[(i)].owner == current->pid))
45 /* Called when a transfer is completed */
46 static void hid_pid_ctrl_out(struct urb *u, struct pt_regs *regs)
48 dev_dbg(&u->dev->dev, "hid_pid_ctrl_out - Transfer Completed\n");
51 static void hid_pid_exit(struct hid_device *hid)
53 struct hid_ff_pid *private = hid->ff_private;
55 if (private->urbffout) {
56 usb_kill_urb(private->urbffout);
57 usb_free_urb(private->urbffout);
61 static int pid_upload_periodic(struct hid_ff_pid *pid, struct ff_effect *effect, int is_update)
63 dev_info(&pid->hid->dev->dev, "requested periodic force upload\n");
67 static int pid_upload_constant(struct hid_ff_pid *pid, struct ff_effect *effect, int is_update)
69 dev_info(&pid->hid->dev->dev, "requested constant force upload\n");
73 static int pid_upload_condition(struct hid_ff_pid *pid, struct ff_effect *effect, int is_update)
75 dev_info(&pid->hid->dev->dev, "requested Condition force upload\n");
79 static int pid_upload_ramp(struct hid_ff_pid *pid, struct ff_effect *effect, int is_update)
81 dev_info(&pid->hid->dev->dev, "request ramp force upload\n");
85 static int hid_pid_event(struct hid_device *hid, struct input_dev *input,
86 unsigned int type, unsigned int code, int value)
88 dev_dbg(&hid->dev->dev, "PID event received: type=%d,code=%d,value=%d.\n", type, code, value);
96 /* Lock must be held by caller */
97 static void hid_pid_ctrl_playback(struct hid_device *hid, struct hid_pid_effect *effect, int play)
100 set_bit(FF_PID_FLAGS_PLAYING, &effect->flags);
102 clear_bit(FF_PID_FLAGS_PLAYING, &effect->flags);
105 static int hid_pid_erase(struct input_dev *dev, int id)
107 struct hid_device *hid = dev->private;
108 struct hid_ff_pid *pid = hid->ff_private;
109 struct hid_field *field;
113 if (!CHECK_OWNERSHIP(id, pid))
117 field = hid_find_field_by_usage(hid, HID_UP_PID | FF_PID_USAGE_BLOCK_FREE,
120 dev_err(&hid->dev->dev, "couldn't find report\n");
124 ret = hid_set_field(field, 0, pid->effects[id].device_id);
126 dev_err(&hid->dev->dev, "couldn't set field\n");
130 hid_submit_report(hid, field->report, USB_DIR_OUT);
132 spin_lock_irqsave(&pid->lock, flags);
133 hid_pid_ctrl_playback(hid, pid->effects + id, 0);
134 pid->effects[id].flags = 0;
135 spin_unlock_irqrestore(&pid->lock, flags);
140 /* Erase all effects this process owns */
141 static int hid_pid_flush(struct input_dev *dev, struct file *file)
143 struct hid_device *hid = dev->private;
144 struct hid_ff_pid *pid = hid->ff_private;
147 /*NOTE: no need to lock here. The only times EFFECT_USED is
148 modified is when effects are uploaded or when an effect is
149 erased. But a process cannot close its dev/input/eventX fd
150 and perform ioctls on the same fd all at the same time */
151 /*FIXME: multiple threads, anyone? */
152 for (i = 0; i < dev->ff_effects_max; ++i)
153 if (current->pid == pid->effects[i].owner
154 && test_bit(FF_PID_FLAGS_USED, &pid->effects[i].flags))
155 if (hid_pid_erase(dev, i))
156 dev_warn(&hid->dev->dev, "erase effect %d failed", i);
161 static int hid_pid_upload_effect(struct input_dev *dev,
162 struct ff_effect *effect)
164 struct hid_ff_pid *pid_private = (struct hid_ff_pid *)(dev->private);
169 dev_dbg(&pid_private->hid->dev->dev, "upload effect called: effect_type=%x\n", effect->type);
170 /* Check this effect type is supported by this device */
171 if (!test_bit(effect->type, dev->ffbit)) {
172 dev_dbg(&pid_private->hid->dev->dev,
173 "invalid kind of effect requested.\n");
178 * If we want to create a new effect, get a free id
180 if (effect->id == -1) {
183 // Spinlock so we don`t get a race condition when choosing IDs
184 spin_lock_irqsave(&pid_private->lock, flags);
186 while (id < FF_EFFECTS_MAX)
187 if (!test_and_set_bit(FF_PID_FLAGS_USED, &pid_private->effects[id++].flags))
190 if (id == FF_EFFECTS_MAX) {
191 spin_unlock_irqrestore(&pid_private->lock, flags);
192 // TEMP - We need to get ff_effects_max correctly first: || id >= dev->ff_effects_max) {
193 dev_dbg(&pid_private->hid->dev->dev, "Not enough device memory\n");
198 dev_dbg(&pid_private->hid->dev->dev, "effect ID is %d.\n", id);
199 pid_private->effects[id].owner = current->pid;
200 pid_private->effects[id].flags = (1 << FF_PID_FLAGS_USED);
201 spin_unlock_irqrestore(&pid_private->lock, flags);
203 is_update = FF_PID_FALSE;
205 /* We want to update an effect */
206 if (!CHECK_OWNERSHIP(effect->id, pid_private))
209 /* Parameter type cannot be updated */
210 if (effect->type != pid_private->effects[effect->id].effect.type)
213 /* Check the effect is not already being updated */
214 if (test_bit(FF_PID_FLAGS_UPDATING, &pid_private->effects[effect->id].flags))
217 is_update = FF_PID_TRUE;
223 switch (effect->type) {
225 ret = pid_upload_periodic(pid_private, effect, is_update);
229 ret = pid_upload_constant(pid_private, effect, is_update);
236 ret = pid_upload_condition(pid_private, effect, is_update);
240 ret = pid_upload_ramp(pid_private, effect, is_update);
244 dev_dbg(&pid_private->hid->dev->dev,
245 "invalid type of effect requested - %x.\n",
249 /* If a packet was sent, forbid new updates until we are notified
250 * that the packet was updated
253 set_bit(FF_PID_FLAGS_UPDATING, &pid_private->effects[effect->id].flags);
254 pid_private->effects[effect->id].effect = *effect;
258 int hid_pid_init(struct hid_device *hid)
260 struct hid_ff_pid *private;
261 struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
262 struct input_dev *input_dev = hidinput->input;
264 private = hid->ff_private = kzalloc(sizeof(struct hid_ff_pid), GFP_KERNEL);
270 hid->ff_exit = hid_pid_exit;
271 hid->ff_event = hid_pid_event;
273 /* Open output URB */
274 if (!(private->urbffout = usb_alloc_urb(0, GFP_KERNEL))) {
279 usb_fill_control_urb(private->urbffout, hid->dev, 0,
280 (void *)&private->ffcr, private->ctrl_buffer, 8,
281 hid_pid_ctrl_out, hid);
283 input_dev->upload_effect = hid_pid_upload_effect;
284 input_dev->flush = hid_pid_flush;
285 input_dev->ff_effects_max = 8; // A random default
286 set_bit(EV_FF, input_dev->evbit);
287 set_bit(EV_FF_STATUS, input_dev->evbit);
289 spin_lock_init(&private->lock);
291 printk(KERN_INFO "Force feedback driver for PID devices by Rodrigo Damazio <rdamazio@lsi.usp.br>.\n");