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authorRalf Baechle <ralf@linux-mips.org>2005-07-25 18:45:45 -0400
committerRalf Baechle <ralf@linux-mips.org>2005-10-29 14:31:57 -0400
commit23fbee9dd5d2a41d36af49ff8e1669fb0c29fda8 (patch)
tree4e24699269b9d4d2655d961e7a0ffb29931e9b2d /arch/mips/tx4938/toshiba_rbtx4938/spi_eeprom.c
parent132940401174ed04f9e8f1ae2dad6f47da26ee0a (diff)
Support for Toshiba's RBHMA4500 eval board for the TX4938.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/tx4938/toshiba_rbtx4938/spi_eeprom.c')
-rw-r--r--arch/mips/tx4938/toshiba_rbtx4938/spi_eeprom.c219
1 files changed, 219 insertions, 0 deletions
diff --git a/arch/mips/tx4938/toshiba_rbtx4938/spi_eeprom.c b/arch/mips/tx4938/toshiba_rbtx4938/spi_eeprom.c
new file mode 100644
index 000000000000..951a208ee9b3
--- /dev/null
+++ b/arch/mips/tx4938/toshiba_rbtx4938/spi_eeprom.c
@@ -0,0 +1,219 @@
1/*
2 * linux/arch/mips/tx4938/toshiba_rbtx4938/spi_eeprom.c
3 * Copyright (C) 2000-2001 Toshiba Corporation
4 *
5 * 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the
6 * terms of the GNU General Public License version 2. This program is
7 * licensed "as is" without any warranty of any kind, whether express
8 * or implied.
9 *
10 * Support for TX4938 in 2.6 - Manish Lachwani (mlachwani@mvista.com)
11 */
12#include <linux/config.h>
13#include <linux/init.h>
14#include <linux/delay.h>
15#include <linux/proc_fs.h>
16#include <linux/spinlock.h>
17#include <asm/tx4938/spi.h>
18#include <asm/tx4938/tx4938.h>
19
20/* ATMEL 250x0 instructions */
21#define ATMEL_WREN 0x06
22#define ATMEL_WRDI 0x04
23#define ATMEL_RDSR 0x05
24#define ATMEL_WRSR 0x01
25#define ATMEL_READ 0x03
26#define ATMEL_WRITE 0x02
27
28#define ATMEL_SR_BSY 0x01
29#define ATMEL_SR_WEN 0x02
30#define ATMEL_SR_BP0 0x04
31#define ATMEL_SR_BP1 0x08
32
33DEFINE_SPINLOCK(spi_eeprom_lock);
34
35static struct spi_dev_desc seeprom_dev_desc = {
36 .baud = 1500000, /* 1.5Mbps */
37 .tcss = 1,
38 .tcsh = 1,
39 .tcsr = 1,
40 .byteorder = 1, /* MSB-First */
41 .polarity = 0, /* High-Active */
42 .phase = 0, /* Sample-Then-Shift */
43
44};
45static inline int
46spi_eeprom_io(int chipid,
47 unsigned char **inbufs, unsigned int *incounts,
48 unsigned char **outbufs, unsigned int *outcounts)
49{
50 return txx9_spi_io(chipid, &seeprom_dev_desc,
51 inbufs, incounts, outbufs, outcounts, 0);
52}
53
54int spi_eeprom_write_enable(int chipid, int enable)
55{
56 unsigned char inbuf[1];
57 unsigned char *inbufs[1];
58 unsigned int incounts[2];
59 unsigned long flags;
60 int stat;
61 inbuf[0] = enable ? ATMEL_WREN : ATMEL_WRDI;
62 inbufs[0] = inbuf;
63 incounts[0] = sizeof(inbuf);
64 incounts[1] = 0;
65 spin_lock_irqsave(&spi_eeprom_lock, flags);
66 stat = spi_eeprom_io(chipid, inbufs, incounts, NULL, NULL);
67 spin_unlock_irqrestore(&spi_eeprom_lock, flags);
68 return stat;
69}
70
71static int spi_eeprom_read_status_nolock(int chipid)
72{
73 unsigned char inbuf[2], outbuf[2];
74 unsigned char *inbufs[1], *outbufs[1];
75 unsigned int incounts[2], outcounts[2];
76 int stat;
77 inbuf[0] = ATMEL_RDSR;
78 inbuf[1] = 0;
79 inbufs[0] = inbuf;
80 incounts[0] = sizeof(inbuf);
81 incounts[1] = 0;
82 outbufs[0] = outbuf;
83 outcounts[0] = sizeof(outbuf);
84 outcounts[1] = 0;
85 stat = spi_eeprom_io(chipid, inbufs, incounts, outbufs, outcounts);
86 if (stat < 0)
87 return stat;
88 return outbuf[1];
89}
90
91int spi_eeprom_read_status(int chipid)
92{
93 unsigned long flags;
94 int stat;
95 spin_lock_irqsave(&spi_eeprom_lock, flags);
96 stat = spi_eeprom_read_status_nolock(chipid);
97 spin_unlock_irqrestore(&spi_eeprom_lock, flags);
98 return stat;
99}
100
101int spi_eeprom_read(int chipid, int address, unsigned char *buf, int len)
102{
103 unsigned char inbuf[2];
104 unsigned char *inbufs[2], *outbufs[2];
105 unsigned int incounts[2], outcounts[3];
106 unsigned long flags;
107 int stat;
108 inbuf[0] = ATMEL_READ;
109 inbuf[1] = address;
110 inbufs[0] = inbuf;
111 inbufs[1] = NULL;
112 incounts[0] = sizeof(inbuf);
113 incounts[1] = 0;
114 outbufs[0] = NULL;
115 outbufs[1] = buf;
116 outcounts[0] = 2;
117 outcounts[1] = len;
118 outcounts[2] = 0;
119 spin_lock_irqsave(&spi_eeprom_lock, flags);
120 stat = spi_eeprom_io(chipid, inbufs, incounts, outbufs, outcounts);
121 spin_unlock_irqrestore(&spi_eeprom_lock, flags);
122 return stat;
123}
124
125int spi_eeprom_write(int chipid, int address, unsigned char *buf, int len)
126{
127 unsigned char inbuf[2];
128 unsigned char *inbufs[2];
129 unsigned int incounts[3];
130 unsigned long flags;
131 int i, stat;
132
133 if (address / 8 != (address + len - 1) / 8)
134 return -EINVAL;
135 stat = spi_eeprom_write_enable(chipid, 1);
136 if (stat < 0)
137 return stat;
138 stat = spi_eeprom_read_status(chipid);
139 if (stat < 0)
140 return stat;
141 if (!(stat & ATMEL_SR_WEN))
142 return -EPERM;
143
144 inbuf[0] = ATMEL_WRITE;
145 inbuf[1] = address;
146 inbufs[0] = inbuf;
147 inbufs[1] = buf;
148 incounts[0] = sizeof(inbuf);
149 incounts[1] = len;
150 incounts[2] = 0;
151 spin_lock_irqsave(&spi_eeprom_lock, flags);
152 stat = spi_eeprom_io(chipid, inbufs, incounts, NULL, NULL);
153 if (stat < 0)
154 goto unlock_return;
155
156 /* write start. max 10ms */
157 for (i = 10; i > 0; i--) {
158 int stat = spi_eeprom_read_status_nolock(chipid);
159 if (stat < 0)
160 goto unlock_return;
161 if (!(stat & ATMEL_SR_BSY))
162 break;
163 mdelay(1);
164 }
165 spin_unlock_irqrestore(&spi_eeprom_lock, flags);
166 if (i == 0)
167 return -EIO;
168 return len;
169 unlock_return:
170 spin_unlock_irqrestore(&spi_eeprom_lock, flags);
171 return stat;
172}
173
174#ifdef CONFIG_PROC_FS
175#define MAX_SIZE 0x80 /* for ATMEL 25010 */
176static int spi_eeprom_read_proc(char *page, char **start, off_t off,
177 int count, int *eof, void *data)
178{
179 unsigned int size = MAX_SIZE;
180 if (spi_eeprom_read((int)data, 0, (unsigned char *)page, size) < 0)
181 size = 0;
182 return size;
183}
184
185static int spi_eeprom_write_proc(struct file *file, const char *buffer,
186 unsigned long count, void *data)
187{
188 unsigned int size = MAX_SIZE;
189 int i;
190 if (file->f_pos >= size)
191 return -EIO;
192 if (file->f_pos + count > size)
193 count = size - file->f_pos;
194 for (i = 0; i < count; i += 8) {
195 int len = count - i < 8 ? count - i : 8;
196 if (spi_eeprom_write((int)data, file->f_pos,
197 (unsigned char *)buffer, len) < 0) {
198 count = -EIO;
199 break;
200 }
201 buffer += len;
202 file->f_pos += len;
203 }
204 return count;
205}
206
207__init void spi_eeprom_proc_create(struct proc_dir_entry *dir, int chipid)
208{
209 struct proc_dir_entry *entry;
210 char name[128];
211 sprintf(name, "seeprom-%d", chipid);
212 entry = create_proc_entry(name, 0600, dir);
213 if (entry) {
214 entry->read_proc = spi_eeprom_read_proc;
215 entry->write_proc = spi_eeprom_write_proc;
216 entry->data = (void *)chipid;
217 }
218}
219#endif /* CONFIG_PROC_FS */
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