drivers/opl4/opl4_proc.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * Functions for the OPL4 proc file
0004  * Copyright (c) 2003 by Clemens Ladisch <clemens@ladisch.de>
0005  */
0006
0007 #include "opl4_local.h"
0008 #include <linux/vmalloc.h>
0009 #include <linux/export.h>
0010 #include <sound/info.h>
0011
0012 static int snd_opl4_mem_proc_open(struct snd_info_entry *entry,
0013                   unsigned short mode, void **file_private_data)
0014 {
0015     struct snd_opl4 *opl4 = entry->private_data;
0016
0017     mutex_lock(&opl4->access_mutex);
0018     if (opl4->memory_access) {
0019         mutex_unlock(&opl4->access_mutex);
0020         return -EBUSY;
0021     }
0022     opl4->memory_access++;
0023     mutex_unlock(&opl4->access_mutex);
0024     return 0;
0025 }
0026
0027 static int snd_opl4_mem_proc_release(struct snd_info_entry *entry,
0028                      unsigned short mode, void *file_private_data)
0029 {
0030     struct snd_opl4 *opl4 = entry->private_data;
0031
0032     mutex_lock(&opl4->access_mutex);
0033     opl4->memory_access--;
0034     mutex_unlock(&opl4->access_mutex);
0035     return 0;
0036 }
0037
0038 static ssize_t snd_opl4_mem_proc_read(struct snd_info_entry *entry,
0039                       void *file_private_data,
0040                       struct file *file, char __user *_buf,
0041                       size_t count, loff_t pos)
0042 {
0043     struct snd_opl4 *opl4 = entry->private_data;
0044     char* buf;
0045
0046     buf = vmalloc(count);
0047     if (!buf)
0048         return -ENOMEM;
0049     snd_opl4_read_memory(opl4, buf, pos, count);
0050     if (copy_to_user(_buf, buf, count)) {
0051         vfree(buf);
0052         return -EFAULT;
0053     }
0054     vfree(buf);
0055     return count;
0056 }
0057
0058 static ssize_t snd_opl4_mem_proc_write(struct snd_info_entry *entry,
0059                        void *file_private_data,
0060                        struct file *file,
0061                        const char __user *_buf,
0062                        size_t count, loff_t pos)
0063 {
0064     struct snd_opl4 *opl4 = entry->private_data;
0065     char *buf;
0066
0067     buf = vmalloc(count);
0068     if (!buf)
0069         return -ENOMEM;
0070     if (copy_from_user(buf, _buf, count)) {
0071         vfree(buf);
0072         return -EFAULT;
0073     }
0074     snd_opl4_write_memory(opl4, buf, pos, count);
0075     vfree(buf);
0076     return count;
0077 }
0078
0079 static const struct snd_info_entry_ops snd_opl4_mem_proc_ops = {
0080     .open = snd_opl4_mem_proc_open,
0081     .release = snd_opl4_mem_proc_release,
0082     .read = snd_opl4_mem_proc_read,
0083     .write = snd_opl4_mem_proc_write,
0084 };
0085
0086 int snd_opl4_create_proc(struct snd_opl4 *opl4)
0087 {
0088     struct snd_info_entry *entry;
0089
0090     entry = snd_info_create_card_entry(opl4->card, "opl4-mem", opl4->card->proc_root);
0091     if (entry) {
0092         if (opl4->hardware < OPL3_HW_OPL4_ML) {
0093             /* OPL4 can access 4 MB external ROM/SRAM */
0094             entry->mode |= 0200;
0095             entry->size = 4 * 1024 * 1024;
0096         } else {
0097             /* OPL4-ML has 1 MB internal ROM */
0098             entry->size = 1 * 1024 * 1024;
0099         }
0100         entry->content = SNDRV_INFO_CONTENT_DATA;
0101         entry->c.ops = &snd_opl4_mem_proc_ops;
0102         entry->module = THIS_MODULE;
0103         entry->private_data = opl4;
0104     }
0105     opl4->proc_entry = entry;
0106     return 0;
0107 }
0108
0109 void snd_opl4_free_proc(struct snd_opl4 *opl4)
0110 {
0111     snd_info_free_entry(opl4->proc_entry);
0112 }