Merge master.kernel.org:/home/rmk/linux-2.6-arm
[linux-2.6] / drivers / usb / input / pid.c
1 /*
2  *  PID Force feedback support for hid devices.
3  *
4  *  Copyright (c) 2002 Rodrigo Damazio.
5  *  Portions by Johann Deneux and Bjorn Augustson
6  */
7
8 /*
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.
13  *
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.
18  *
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
22  *
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>
25  */
26
27 #include <linux/config.h>
28 #include <linux/module.h>
29 #include <linux/slab.h>
30 #include <linux/kernel.h>
31 #include <linux/init.h>
32 #include <linux/mm.h>
33 #include <linux/smp_lock.h>
34 #include <linux/spinlock.h>
35 #include <linux/input.h>
36 #include <linux/usb.h>
37 #include "hid.h"
38 #include "pid.h"
39
40 #define CHECK_OWNERSHIP(i, hid_pid)     \
41         ((i) < FF_EFFECTS_MAX && i >= 0 && \
42         test_bit(FF_PID_FLAGS_USED, &hid_pid->effects[(i)].flags) && \
43         (current->pid == 0 || \
44         (hid_pid)->effects[(i)].owner == current->pid))
45
46 /* Called when a transfer is completed */
47 static void hid_pid_ctrl_out(struct urb *u, struct pt_regs *regs)
48 {
49         dev_dbg(&u->dev->dev, "hid_pid_ctrl_out - Transfer Completed\n");
50 }
51
52 static void hid_pid_exit(struct hid_device *hid)
53 {
54         struct hid_ff_pid *private = hid->ff_private;
55
56         if (private->urbffout) {
57                 usb_kill_urb(private->urbffout);
58                 usb_free_urb(private->urbffout);
59         }
60 }
61
62 static int pid_upload_periodic(struct hid_ff_pid *pid, struct ff_effect *effect, int is_update)
63 {
64         dev_info(&pid->hid->dev->dev, "requested periodic force upload\n");
65         return 0;
66 }
67
68 static int pid_upload_constant(struct hid_ff_pid *pid, struct ff_effect *effect, int is_update)
69 {
70         dev_info(&pid->hid->dev->dev, "requested constant force upload\n");
71         return 0;
72 }
73
74 static int pid_upload_condition(struct hid_ff_pid *pid, struct ff_effect *effect, int is_update)
75 {
76         dev_info(&pid->hid->dev->dev, "requested Condition force upload\n");
77         return 0;
78 }
79
80 static int pid_upload_ramp(struct hid_ff_pid *pid, struct ff_effect *effect, int is_update)
81 {
82         dev_info(&pid->hid->dev->dev, "request ramp force upload\n");
83         return 0;
84 }
85
86 static int hid_pid_event(struct hid_device *hid, struct input_dev *input,
87                          unsigned int type, unsigned int code, int value)
88 {
89         dev_dbg(&hid->dev->dev, "PID event received: type=%d,code=%d,value=%d.\n", type, code, value);
90
91         if (type != EV_FF)
92                 return -1;
93
94         return 0;
95 }
96
97 /* Lock must be held by caller */
98 static void hid_pid_ctrl_playback(struct hid_device *hid, struct hid_pid_effect *effect, int play)
99 {
100         if (play)
101                 set_bit(FF_PID_FLAGS_PLAYING, &effect->flags);
102         else
103                 clear_bit(FF_PID_FLAGS_PLAYING, &effect->flags);
104 }
105
106 static int hid_pid_erase(struct input_dev *dev, int id)
107 {
108         struct hid_device *hid = dev->private;
109         struct hid_ff_pid *pid = hid->ff_private;
110         struct hid_field *field;
111         unsigned long flags;
112         int ret;
113
114         if (!CHECK_OWNERSHIP(id, pid))
115                 return -EACCES;
116
117         /* Find report */
118         field = hid_find_field_by_usage(hid, HID_UP_PID | FF_PID_USAGE_BLOCK_FREE,
119                                         HID_OUTPUT_REPORT);
120         if (!field) {
121                 dev_err(&hid->dev->dev, "couldn't find report\n");
122                 return -EIO;
123         }
124
125         ret = hid_set_field(field, 0, pid->effects[id].device_id);
126         if (ret) {
127                 dev_err(&hid->dev->dev, "couldn't set field\n");
128                 return ret;
129         }
130
131         hid_submit_report(hid, field->report, USB_DIR_OUT);
132
133         spin_lock_irqsave(&pid->lock, flags);
134         hid_pid_ctrl_playback(hid, pid->effects + id, 0);
135         pid->effects[id].flags = 0;
136         spin_unlock_irqrestore(&pid->lock, flags);
137
138         return 0;
139 }
140
141 /* Erase all effects this process owns */
142 static int hid_pid_flush(struct input_dev *dev, struct file *file)
143 {
144         struct hid_device *hid = dev->private;
145         struct hid_ff_pid *pid = hid->ff_private;
146         int i;
147
148         /*NOTE: no need to lock here. The only times EFFECT_USED is
149            modified is when effects are uploaded or when an effect is
150            erased. But a process cannot close its dev/input/eventX fd
151            and perform ioctls on the same fd all at the same time */
152         /*FIXME: multiple threads, anyone? */
153         for (i = 0; i < dev->ff_effects_max; ++i)
154                 if (current->pid == pid->effects[i].owner
155                     && test_bit(FF_PID_FLAGS_USED, &pid->effects[i].flags))
156                         if (hid_pid_erase(dev, i))
157                                 dev_warn(&hid->dev->dev, "erase effect %d failed", i);
158
159         return 0;
160 }
161
162 static int hid_pid_upload_effect(struct input_dev *dev,
163                                  struct ff_effect *effect)
164 {
165         struct hid_ff_pid *pid_private = (struct hid_ff_pid *)(dev->private);
166         int ret;
167         int is_update;
168         unsigned long flags;
169
170         dev_dbg(&pid_private->hid->dev->dev, "upload effect called: effect_type=%x\n", effect->type);
171         /* Check this effect type is supported by this device */
172         if (!test_bit(effect->type, dev->ffbit)) {
173                 dev_dbg(&pid_private->hid->dev->dev,
174                         "invalid kind of effect requested.\n");
175                 return -EINVAL;
176         }
177
178         /*
179          * If we want to create a new effect, get a free id
180          */
181         if (effect->id == -1) {
182                 int id = 0;
183
184                 // Spinlock so we don`t get a race condition when choosing IDs
185                 spin_lock_irqsave(&pid_private->lock, flags);
186
187                 while (id < FF_EFFECTS_MAX)
188                         if (!test_and_set_bit(FF_PID_FLAGS_USED, &pid_private->effects[id++].flags))
189                                 break;
190
191                 if (id == FF_EFFECTS_MAX) {
192                         spin_unlock_irqrestore(&pid_private->lock, flags);
193 // TEMP - We need to get ff_effects_max correctly first:  || id >= dev->ff_effects_max) {
194                         dev_dbg(&pid_private->hid->dev->dev, "Not enough device memory\n");
195                         return -ENOMEM;
196                 }
197
198                 effect->id = id;
199                 dev_dbg(&pid_private->hid->dev->dev, "effect ID is %d.\n", id);
200                 pid_private->effects[id].owner = current->pid;
201                 pid_private->effects[id].flags = (1 << FF_PID_FLAGS_USED);
202                 spin_unlock_irqrestore(&pid_private->lock, flags);
203
204                 is_update = FF_PID_FALSE;
205         } else {
206                 /* We want to update an effect */
207                 if (!CHECK_OWNERSHIP(effect->id, pid_private))
208                         return -EACCES;
209
210                 /* Parameter type cannot be updated */
211                 if (effect->type != pid_private->effects[effect->id].effect.type)
212                         return -EINVAL;
213
214                 /* Check the effect is not already being updated */
215                 if (test_bit(FF_PID_FLAGS_UPDATING, &pid_private->effects[effect->id].flags))
216                         return -EAGAIN;
217
218                 is_update = FF_PID_TRUE;
219         }
220
221         /*
222          * Upload the effect
223          */
224         switch (effect->type) {
225         case FF_PERIODIC:
226                 ret = pid_upload_periodic(pid_private, effect, is_update);
227                 break;
228
229         case FF_CONSTANT:
230                 ret = pid_upload_constant(pid_private, effect, is_update);
231                 break;
232
233         case FF_SPRING:
234         case FF_FRICTION:
235         case FF_DAMPER:
236         case FF_INERTIA:
237                 ret = pid_upload_condition(pid_private, effect, is_update);
238                 break;
239
240         case FF_RAMP:
241                 ret = pid_upload_ramp(pid_private, effect, is_update);
242                 break;
243
244         default:
245                 dev_dbg(&pid_private->hid->dev->dev,
246                         "invalid type of effect requested - %x.\n",
247                         effect->type);
248                 return -EINVAL;
249         }
250         /* If a packet was sent, forbid new updates until we are notified
251          * that the packet was updated
252          */
253         if (ret == 0)
254                 set_bit(FF_PID_FLAGS_UPDATING, &pid_private->effects[effect->id].flags);
255         pid_private->effects[effect->id].effect = *effect;
256         return ret;
257 }
258
259 int hid_pid_init(struct hid_device *hid)
260 {
261         struct hid_ff_pid *private;
262         struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
263         struct input_dev *input_dev = hidinput->input;
264
265         private = hid->ff_private = kzalloc(sizeof(struct hid_ff_pid), GFP_KERNEL);
266         if (!private)
267                 return -ENOMEM;
268
269         private->hid = hid;
270
271         hid->ff_exit = hid_pid_exit;
272         hid->ff_event = hid_pid_event;
273
274         /* Open output URB */
275         if (!(private->urbffout = usb_alloc_urb(0, GFP_KERNEL))) {
276                 kfree(private);
277                 return -1;
278         }
279
280         usb_fill_control_urb(private->urbffout, hid->dev, 0,
281                              (void *)&private->ffcr, private->ctrl_buffer, 8,
282                              hid_pid_ctrl_out, hid);
283
284         input_dev->upload_effect = hid_pid_upload_effect;
285         input_dev->flush = hid_pid_flush;
286         input_dev->ff_effects_max = 8;  // A random default
287         set_bit(EV_FF, input_dev->evbit);
288         set_bit(EV_FF_STATUS, input_dev->evbit);
289
290         spin_lock_init(&private->lock);
291
292         printk(KERN_INFO "Force feedback driver for PID devices by Rodrigo Damazio <rdamazio@lsi.usp.br>.\n");
293
294         return 0;
295 }