gus_dram.c

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 4 *  DRAM access routines
 5 */
 6
 7#include <linux/time.h>
 8#include <sound/core.h>
 9#include <sound/gus.h>
10#include <sound/info.h>
11
12
13static int snd_gus_dram_poke(struct snd_gus_card *gus, char __user *_buffer,
14			     unsigned int address, unsigned int size)
15{
16	unsigned int size1, size2;
17	char buffer[256], *pbuffer;
18
19	while (size > 0) {
20		size1 = size > sizeof(buffer) ? sizeof(buffer) : size;
21		if (copy_from_user(buffer, _buffer, size1))
22			return -EFAULT;
23		if (gus->interwave) {
24			guard(spinlock_irqsave)(&gus->reg_lock);
25			snd_gf1_write8(gus, SNDRV_GF1_GB_MEMORY_CONTROL, 0x01);
26			snd_gf1_dram_addr(gus, address);
27			outsb(GUSP(gus, DRAM), buffer, size1);
28			address += size1;
29		} else {
30			pbuffer = buffer;
31			size2 = size1;
32			while (size2--)
33				snd_gf1_poke(gus, address++, *pbuffer++);
34		}
35		size -= size1;
36		_buffer += size1;
37	}
38	return 0;
39}
40
41
42int snd_gus_dram_write(struct snd_gus_card *gus, char __user *buffer,
43		       unsigned int address, unsigned int size)
44{
45	return snd_gus_dram_poke(gus, buffer, address, size);
46}
47
48static int snd_gus_dram_peek(struct snd_gus_card *gus, char __user *_buffer,
49			     unsigned int address, unsigned int size,
50			     int rom)
51{
52	unsigned int size1, size2;
53	char buffer[256], *pbuffer;
54
55	while (size > 0) {
56		size1 = size > sizeof(buffer) ? sizeof(buffer) : size;
57		if (gus->interwave) {
58			guard(spinlock_irqsave)(&gus->reg_lock);
59			snd_gf1_write8(gus, SNDRV_GF1_GB_MEMORY_CONTROL, rom ? 0x03 : 0x01);
60			snd_gf1_dram_addr(gus, address);
61			insb(GUSP(gus, DRAM), buffer, size1);
62			snd_gf1_write8(gus, SNDRV_GF1_GB_MEMORY_CONTROL, 0x01);
63			address += size1;
64		} else {
65			pbuffer = buffer;
66			size2 = size1;
67			while (size2--)
68				*pbuffer++ = snd_gf1_peek(gus, address++);
69		}
70		if (copy_to_user(_buffer, buffer, size1))
71			return -EFAULT;
72		size -= size1;
73		_buffer += size1;
74	}
75	return 0;
76}
77
78int snd_gus_dram_read(struct snd_gus_card *gus, char __user *buffer,
79		      unsigned int address, unsigned int size,
80		      int rom)
81{
82	return snd_gus_dram_peek(gus, buffer, address, size, rom);
83}