Merge tag 'mailbox-v4.15' of git://git.linaro.org/landing-teams/working/fujitsu/integ...
[sfrench/cifs-2.6.git] / drivers / mailbox / mailbox-test.c
1 /*
2  * Copyright (C) 2015 ST Microelectronics
3  *
4  * Author: Lee Jones <lee.jones@linaro.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11
12 #include <linux/debugfs.h>
13 #include <linux/err.h>
14 #include <linux/fs.h>
15 #include <linux/io.h>
16 #include <linux/kernel.h>
17 #include <linux/mailbox_client.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/platform_device.h>
21 #include <linux/poll.h>
22 #include <linux/slab.h>
23 #include <linux/uaccess.h>
24 #include <linux/sched/signal.h>
25
26 #define MBOX_MAX_SIG_LEN        8
27 #define MBOX_MAX_MSG_LEN        128
28 #define MBOX_BYTES_PER_LINE     16
29 #define MBOX_HEXDUMP_LINE_LEN   ((MBOX_BYTES_PER_LINE * 4) + 2)
30 #define MBOX_HEXDUMP_MAX_LEN    (MBOX_HEXDUMP_LINE_LEN *                \
31                                  (MBOX_MAX_MSG_LEN / MBOX_BYTES_PER_LINE))
32
33 static bool mbox_data_ready;
34 static struct dentry *root_debugfs_dir;
35
36 struct mbox_test_device {
37         struct device           *dev;
38         void __iomem            *tx_mmio;
39         void __iomem            *rx_mmio;
40         struct mbox_chan        *tx_channel;
41         struct mbox_chan        *rx_channel;
42         char                    *rx_buffer;
43         char                    *signal;
44         char                    *message;
45         spinlock_t              lock;
46         wait_queue_head_t       waitq;
47         struct fasync_struct    *async_queue;
48 };
49
50 static ssize_t mbox_test_signal_write(struct file *filp,
51                                        const char __user *userbuf,
52                                        size_t count, loff_t *ppos)
53 {
54         struct mbox_test_device *tdev = filp->private_data;
55
56         if (!tdev->tx_channel) {
57                 dev_err(tdev->dev, "Channel cannot do Tx\n");
58                 return -EINVAL;
59         }
60
61         if (count > MBOX_MAX_SIG_LEN) {
62                 dev_err(tdev->dev,
63                         "Signal length %zd greater than max allowed %d\n",
64                         count, MBOX_MAX_SIG_LEN);
65                 return -EINVAL;
66         }
67
68         /* Only allocate memory if we need to */
69         if (!tdev->signal) {
70                 tdev->signal = kzalloc(MBOX_MAX_SIG_LEN, GFP_KERNEL);
71                 if (!tdev->signal)
72                         return -ENOMEM;
73         }
74
75         if (copy_from_user(tdev->signal, userbuf, count)) {
76                 kfree(tdev->signal);
77                 tdev->signal = NULL;
78                 return -EFAULT;
79         }
80
81         return count;
82 }
83
84 static const struct file_operations mbox_test_signal_ops = {
85         .write  = mbox_test_signal_write,
86         .open   = simple_open,
87         .llseek = generic_file_llseek,
88 };
89
90 static int mbox_test_message_fasync(int fd, struct file *filp, int on)
91 {
92         struct mbox_test_device *tdev = filp->private_data;
93
94         return fasync_helper(fd, filp, on, &tdev->async_queue);
95 }
96
97 static ssize_t mbox_test_message_write(struct file *filp,
98                                        const char __user *userbuf,
99                                        size_t count, loff_t *ppos)
100 {
101         struct mbox_test_device *tdev = filp->private_data;
102         void *data;
103         int ret;
104
105         if (!tdev->tx_channel) {
106                 dev_err(tdev->dev, "Channel cannot do Tx\n");
107                 return -EINVAL;
108         }
109
110         if (count > MBOX_MAX_MSG_LEN) {
111                 dev_err(tdev->dev,
112                         "Message length %zd greater than max allowed %d\n",
113                         count, MBOX_MAX_MSG_LEN);
114                 return -EINVAL;
115         }
116
117         tdev->message = kzalloc(MBOX_MAX_MSG_LEN, GFP_KERNEL);
118         if (!tdev->message)
119                 return -ENOMEM;
120
121         ret = copy_from_user(tdev->message, userbuf, count);
122         if (ret) {
123                 ret = -EFAULT;
124                 goto out;
125         }
126
127         /*
128          * A separate signal is only of use if there is
129          * MMIO to subsequently pass the message through
130          */
131         if (tdev->tx_mmio && tdev->signal) {
132                 print_hex_dump_bytes("Client: Sending: Signal: ", DUMP_PREFIX_ADDRESS,
133                                      tdev->signal, MBOX_MAX_SIG_LEN);
134
135                 data = tdev->signal;
136         } else
137                 data = tdev->message;
138
139         print_hex_dump_bytes("Client: Sending: Message: ", DUMP_PREFIX_ADDRESS,
140                              tdev->message, MBOX_MAX_MSG_LEN);
141
142         ret = mbox_send_message(tdev->tx_channel, data);
143         if (ret < 0)
144                 dev_err(tdev->dev, "Failed to send message via mailbox\n");
145
146 out:
147         kfree(tdev->signal);
148         kfree(tdev->message);
149         tdev->signal = NULL;
150
151         return ret < 0 ? ret : count;
152 }
153
154 static bool mbox_test_message_data_ready(struct mbox_test_device *tdev)
155 {
156         bool data_ready;
157         unsigned long flags;
158
159         spin_lock_irqsave(&tdev->lock, flags);
160         data_ready = mbox_data_ready;
161         spin_unlock_irqrestore(&tdev->lock, flags);
162
163         return data_ready;
164 }
165
166 static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf,
167                                       size_t count, loff_t *ppos)
168 {
169         struct mbox_test_device *tdev = filp->private_data;
170         unsigned long flags;
171         char *touser, *ptr;
172         int l = 0;
173         int ret;
174
175         DECLARE_WAITQUEUE(wait, current);
176
177         touser = kzalloc(MBOX_HEXDUMP_MAX_LEN + 1, GFP_KERNEL);
178         if (!touser)
179                 return -ENOMEM;
180
181         if (!tdev->rx_channel) {
182                 ret = snprintf(touser, 20, "<NO RX CAPABILITY>\n");
183                 ret = simple_read_from_buffer(userbuf, count, ppos,
184                                               touser, ret);
185                 goto kfree_err;
186         }
187
188         add_wait_queue(&tdev->waitq, &wait);
189
190         do {
191                 __set_current_state(TASK_INTERRUPTIBLE);
192
193                 if (mbox_test_message_data_ready(tdev))
194                         break;
195
196                 if (filp->f_flags & O_NONBLOCK) {
197                         ret = -EAGAIN;
198                         goto waitq_err;
199                 }
200
201                 if (signal_pending(current)) {
202                         ret = -ERESTARTSYS;
203                         goto waitq_err;
204                 }
205                 schedule();
206
207         } while (1);
208
209         spin_lock_irqsave(&tdev->lock, flags);
210
211         ptr = tdev->rx_buffer;
212         while (l < MBOX_HEXDUMP_MAX_LEN) {
213                 hex_dump_to_buffer(ptr,
214                                    MBOX_BYTES_PER_LINE,
215                                    MBOX_BYTES_PER_LINE, 1, touser + l,
216                                    MBOX_HEXDUMP_LINE_LEN, true);
217
218                 ptr += MBOX_BYTES_PER_LINE;
219                 l += MBOX_HEXDUMP_LINE_LEN;
220                 *(touser + (l - 1)) = '\n';
221         }
222         *(touser + l) = '\0';
223
224         memset(tdev->rx_buffer, 0, MBOX_MAX_MSG_LEN);
225         mbox_data_ready = false;
226
227         spin_unlock_irqrestore(&tdev->lock, flags);
228
229         ret = simple_read_from_buffer(userbuf, count, ppos, touser, MBOX_HEXDUMP_MAX_LEN);
230 waitq_err:
231         __set_current_state(TASK_RUNNING);
232         remove_wait_queue(&tdev->waitq, &wait);
233 kfree_err:
234         kfree(touser);
235         return ret;
236 }
237
238 static unsigned int
239 mbox_test_message_poll(struct file *filp, struct poll_table_struct *wait)
240 {
241         struct mbox_test_device *tdev = filp->private_data;
242
243         poll_wait(filp, &tdev->waitq, wait);
244
245         if (mbox_test_message_data_ready(tdev))
246                 return POLLIN | POLLRDNORM;
247         return 0;
248 }
249
250 static const struct file_operations mbox_test_message_ops = {
251         .write  = mbox_test_message_write,
252         .read   = mbox_test_message_read,
253         .fasync = mbox_test_message_fasync,
254         .poll   = mbox_test_message_poll,
255         .open   = simple_open,
256         .llseek = generic_file_llseek,
257 };
258
259 static int mbox_test_add_debugfs(struct platform_device *pdev,
260                                  struct mbox_test_device *tdev)
261 {
262         if (!debugfs_initialized())
263                 return 0;
264
265         root_debugfs_dir = debugfs_create_dir("mailbox", NULL);
266         if (!root_debugfs_dir) {
267                 dev_err(&pdev->dev, "Failed to create Mailbox debugfs\n");
268                 return -EINVAL;
269         }
270
271         debugfs_create_file("message", 0600, root_debugfs_dir,
272                             tdev, &mbox_test_message_ops);
273
274         debugfs_create_file("signal", 0200, root_debugfs_dir,
275                             tdev, &mbox_test_signal_ops);
276
277         return 0;
278 }
279
280 static void mbox_test_receive_message(struct mbox_client *client, void *message)
281 {
282         struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
283         unsigned long flags;
284
285         spin_lock_irqsave(&tdev->lock, flags);
286         if (tdev->rx_mmio) {
287                 memcpy_fromio(tdev->rx_buffer, tdev->rx_mmio, MBOX_MAX_MSG_LEN);
288                 print_hex_dump_bytes("Client: Received [MMIO]: ", DUMP_PREFIX_ADDRESS,
289                                      tdev->rx_buffer, MBOX_MAX_MSG_LEN);
290         } else if (message) {
291                 print_hex_dump_bytes("Client: Received [API]: ", DUMP_PREFIX_ADDRESS,
292                                      message, MBOX_MAX_MSG_LEN);
293                 memcpy(tdev->rx_buffer, message, MBOX_MAX_MSG_LEN);
294         }
295         mbox_data_ready = true;
296         spin_unlock_irqrestore(&tdev->lock, flags);
297
298         wake_up_interruptible(&tdev->waitq);
299
300         kill_fasync(&tdev->async_queue, SIGIO, POLL_IN);
301 }
302
303 static void mbox_test_prepare_message(struct mbox_client *client, void *message)
304 {
305         struct mbox_test_device *tdev = dev_get_drvdata(client->dev);
306
307         if (tdev->tx_mmio) {
308                 if (tdev->signal)
309                         memcpy_toio(tdev->tx_mmio, tdev->message, MBOX_MAX_MSG_LEN);
310                 else
311                         memcpy_toio(tdev->tx_mmio, message, MBOX_MAX_MSG_LEN);
312         }
313 }
314
315 static void mbox_test_message_sent(struct mbox_client *client,
316                                    void *message, int r)
317 {
318         if (r)
319                 dev_warn(client->dev,
320                          "Client: Message could not be sent: %d\n", r);
321         else
322                 dev_info(client->dev,
323                          "Client: Message sent\n");
324 }
325
326 static struct mbox_chan *
327 mbox_test_request_channel(struct platform_device *pdev, const char *name)
328 {
329         struct mbox_client *client;
330         struct mbox_chan *channel;
331
332         client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL);
333         if (!client)
334                 return ERR_PTR(-ENOMEM);
335
336         client->dev             = &pdev->dev;
337         client->rx_callback     = mbox_test_receive_message;
338         client->tx_prepare      = mbox_test_prepare_message;
339         client->tx_done         = mbox_test_message_sent;
340         client->tx_block        = true;
341         client->knows_txdone    = false;
342         client->tx_tout         = 500;
343
344         channel = mbox_request_channel_byname(client, name);
345         if (IS_ERR(channel)) {
346                 dev_warn(&pdev->dev, "Failed to request %s channel\n", name);
347                 return NULL;
348         }
349
350         return channel;
351 }
352
353 static int mbox_test_probe(struct platform_device *pdev)
354 {
355         struct mbox_test_device *tdev;
356         struct resource *res;
357         resource_size_t size;
358         int ret;
359
360         tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL);
361         if (!tdev)
362                 return -ENOMEM;
363
364         /* It's okay for MMIO to be NULL */
365         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
366         size = resource_size(res);
367         tdev->tx_mmio = devm_ioremap_resource(&pdev->dev, res);
368         if (PTR_ERR(tdev->tx_mmio) == -EBUSY)
369                 /* if reserved area in SRAM, try just ioremap */
370                 tdev->tx_mmio = devm_ioremap(&pdev->dev, res->start, size);
371         else if (IS_ERR(tdev->tx_mmio))
372                 tdev->tx_mmio = NULL;
373
374         /* If specified, second reg entry is Rx MMIO */
375         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
376         size = resource_size(res);
377         tdev->rx_mmio = devm_ioremap_resource(&pdev->dev, res);
378         if (PTR_ERR(tdev->rx_mmio) == -EBUSY)
379                 tdev->rx_mmio = devm_ioremap(&pdev->dev, res->start, size);
380         else if (IS_ERR(tdev->rx_mmio))
381                 tdev->rx_mmio = tdev->tx_mmio;
382
383         tdev->tx_channel = mbox_test_request_channel(pdev, "tx");
384         tdev->rx_channel = mbox_test_request_channel(pdev, "rx");
385
386         if (!tdev->tx_channel && !tdev->rx_channel)
387                 return -EPROBE_DEFER;
388
389         /* If Rx is not specified but has Rx MMIO, then Rx = Tx */
390         if (!tdev->rx_channel && (tdev->rx_mmio != tdev->tx_mmio))
391                 tdev->rx_channel = tdev->tx_channel;
392
393         tdev->dev = &pdev->dev;
394         platform_set_drvdata(pdev, tdev);
395
396         spin_lock_init(&tdev->lock);
397
398         if (tdev->rx_channel) {
399                 tdev->rx_buffer = devm_kzalloc(&pdev->dev,
400                                                MBOX_MAX_MSG_LEN, GFP_KERNEL);
401                 if (!tdev->rx_buffer)
402                         return -ENOMEM;
403         }
404
405         ret = mbox_test_add_debugfs(pdev, tdev);
406         if (ret)
407                 return ret;
408
409         init_waitqueue_head(&tdev->waitq);
410         dev_info(&pdev->dev, "Successfully registered\n");
411
412         return 0;
413 }
414
415 static int mbox_test_remove(struct platform_device *pdev)
416 {
417         struct mbox_test_device *tdev = platform_get_drvdata(pdev);
418
419         debugfs_remove_recursive(root_debugfs_dir);
420
421         if (tdev->tx_channel)
422                 mbox_free_channel(tdev->tx_channel);
423         if (tdev->rx_channel)
424                 mbox_free_channel(tdev->rx_channel);
425
426         return 0;
427 }
428
429 static const struct of_device_id mbox_test_match[] = {
430         { .compatible = "mailbox-test" },
431         {},
432 };
433 MODULE_DEVICE_TABLE(of, mbox_test_match);
434
435 static struct platform_driver mbox_test_driver = {
436         .driver = {
437                 .name = "mailbox_test",
438                 .of_match_table = mbox_test_match,
439         },
440         .probe  = mbox_test_probe,
441         .remove = mbox_test_remove,
442 };
443 module_platform_driver(mbox_test_driver);
444
445 MODULE_DESCRIPTION("Generic Mailbox Testing Facility");
446 MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org");
447 MODULE_LICENSE("GPL v2");