dtc2278.c revision 2bfba3c444fe8b2ab1c38112a89d8f03b61136ca 
1/*
2 *  Copyright (C) 1996  Linus Torvalds & author (see below)
3 */
4
5#include <linux/module.h>
6#include <linux/types.h>
7#include <linux/kernel.h>
8#include <linux/delay.h>
9#include <linux/timer.h>
10#include <linux/mm.h>
11#include <linux/ioport.h>
12#include <linux/blkdev.h>
13#include <linux/ide.h>
14#include <linux/init.h>
15
16#include <asm/io.h>
17
18#define DRV_NAME "dtc2278"
19
20/*
21 * Changing this #undef to #define may solve start up problems in some systems.
22 */
23#undef ALWAYS_SET_DTC2278_PIO_MODE
24
25/*
26 * From: andy@cercle.cts.com (Dyan Wile)
27 *
28 * Below is a patch for DTC-2278 - alike software-programmable controllers
29 * The code enables the secondary IDE controller and the PIO4 (3?) timings on
30 * the primary (EIDE). You may probably have to enable the 32-bit support to
31 * get the full speed. You better get the disk interrupts disabled ( hdparm -u0
32 * /dev/hd.. ) for the drives connected to the EIDE interface. (I get my
33 * filesystem  corrupted with -u1, but under heavy disk load only :-)
34 *
35 * This card is now forced to use the "serialize" feature,
36 * and irq-unmasking is disallowed.  If io_32bit is enabled,
37 * it must be done for BOTH drives on each interface.
38 *
39 * This code was written for the DTC2278E, but might work with any of these:
40 *
41 * DTC2278S has only a single IDE interface.
42 * DTC2278D has two IDE interfaces and is otherwise identical to the S version.
43 * DTC2278E also has serial ports and a printer port
44 * DTC2278EB: has onboard BIOS, and "works like a charm" -- Kent Bradford <kent@theory.caltech.edu>
45 *
46 * There may be a fourth controller type. The S and D versions use the
47 * Winbond chip, and I think the E version does also.
48 *
49 */
50
51static void sub22 (char b, char c)
52{
53	int i;
54
55	for(i = 0; i < 3; ++i) {
56		inb(0x3f6);
57		outb_p(b,0xb0);
58		inb(0x3f6);
59		outb_p(c,0xb4);
60		inb(0x3f6);
61		if(inb(0xb4) == c) {
62			outb_p(7,0xb0);
63			inb(0x3f6);
64			return;	/* success */
65		}
66	}
67}
68
69static DEFINE_SPINLOCK(dtc2278_lock);
70
71static void dtc2278_set_pio_mode(ide_drive_t *drive, const u8 pio)
72{
73	unsigned long flags;
74
75	if (pio >= 3) {
76		spin_lock_irqsave(&dtc2278_lock, flags);
77		/*
78		 * This enables PIO mode4 (3?) on the first interface
79		 */
80		sub22(1,0xc3);
81		sub22(0,0xa0);
82		spin_unlock_irqrestore(&dtc2278_lock, flags);
83	} else {
84		/* we don't know how to set it back again.. */
85		/* Actually we do - there is a data sheet available for the
86		   Winbond but does anyone actually care */
87	}
88}
89
90static const struct ide_port_ops dtc2278_port_ops = {
91	.set_pio_mode		= dtc2278_set_pio_mode,
92};
93
94static const struct ide_port_info dtc2278_port_info __initdata = {
95	.name			= DRV_NAME,
96	.chipset		= ide_dtc2278,
97	.port_ops		= &dtc2278_port_ops,
98	.host_flags		= IDE_HFLAG_SERIALIZE |
99				  IDE_HFLAG_NO_UNMASK_IRQS |
100				  IDE_HFLAG_IO_32BIT |
101				  /* disallow ->io_32bit changes */
102				  IDE_HFLAG_NO_IO_32BIT |
103				  IDE_HFLAG_NO_DMA,
104	.pio_mask		= ATA_PIO4,
105};
106
107static int __init dtc2278_probe(void)
108{
109	unsigned long flags;
110
111	local_irq_save(flags);
112	/*
113	 * This enables the second interface
114	 */
115	outb_p(4,0xb0);
116	inb(0x3f6);
117	outb_p(0x20,0xb4);
118	inb(0x3f6);
119#ifdef ALWAYS_SET_DTC2278_PIO_MODE
120	/*
121	 * This enables PIO mode4 (3?) on the first interface
122	 * and may solve start-up problems for some people.
123	 */
124	sub22(1,0xc3);
125	sub22(0,0xa0);
126#endif
127	local_irq_restore(flags);
128
129	return ide_legacy_device_add(&dtc2278_port_info, 0);
130}
131
132static int probe_dtc2278;
133
134module_param_named(probe, probe_dtc2278, bool, 0);
135MODULE_PARM_DESC(probe, "probe for DTC2278xx chipsets");
136
137static int __init dtc2278_init(void)
138{
139	if (probe_dtc2278 == 0)
140		return -ENODEV;
141
142	if (dtc2278_probe()) {
143		printk(KERN_ERR "dtc2278: ide interfaces already in use!\n");
144		return -EBUSY;
145	}
146	return 0;
147}
148
149module_init(dtc2278_init);
150
151MODULE_AUTHOR("See Local File");
152MODULE_DESCRIPTION("support of DTC-2278 VLB IDE chipsets");
153MODULE_LICENSE("GPL");
154