blob: 435fe85286801c7a6cb2037d66566316cb154b72 [file] [log] [blame]
Mark A. Greerae4b3fb2007-05-12 10:54:53 +10001/*
2 * Bootloader version of the i2c driver for the MV64x60.
3 *
4 * Author: Dale Farnsworth <dfarnsworth@mvista.com>
5 * Maintained by: Mark A. Greer <mgreer@mvista.com>
6 *
7 * 2003, 2007 (c) MontaVista, Software, Inc. This file is licensed under
8 * the terms of the GNU General Public License version 2. This program is
9 * licensed "as is" without any warranty of any kind, whether express or
10 * implied.
11 */
12
13#include <stdarg.h>
14#include <stddef.h>
15#include "types.h"
16#include "elf.h"
17#include "page.h"
18#include "string.h"
19#include "stdio.h"
20#include "io.h"
21#include "ops.h"
22#include "mv64x60.h"
23
24extern void udelay(long);
25
26/* Register defines */
27#define MV64x60_I2C_REG_SLAVE_ADDR 0x00
28#define MV64x60_I2C_REG_DATA 0x04
29#define MV64x60_I2C_REG_CONTROL 0x08
30#define MV64x60_I2C_REG_STATUS 0x0c
31#define MV64x60_I2C_REG_BAUD 0x0c
32#define MV64x60_I2C_REG_EXT_SLAVE_ADDR 0x10
33#define MV64x60_I2C_REG_SOFT_RESET 0x1c
34
35#define MV64x60_I2C_CONTROL_ACK 0x04
36#define MV64x60_I2C_CONTROL_IFLG 0x08
37#define MV64x60_I2C_CONTROL_STOP 0x10
38#define MV64x60_I2C_CONTROL_START 0x20
39#define MV64x60_I2C_CONTROL_TWSIEN 0x40
40#define MV64x60_I2C_CONTROL_INTEN 0x80
41
42#define MV64x60_I2C_STATUS_BUS_ERR 0x00
43#define MV64x60_I2C_STATUS_MAST_START 0x08
44#define MV64x60_I2C_STATUS_MAST_REPEAT_START 0x10
45#define MV64x60_I2C_STATUS_MAST_WR_ADDR_ACK 0x18
46#define MV64x60_I2C_STATUS_MAST_WR_ADDR_NO_ACK 0x20
47#define MV64x60_I2C_STATUS_MAST_WR_ACK 0x28
48#define MV64x60_I2C_STATUS_MAST_WR_NO_ACK 0x30
49#define MV64x60_I2C_STATUS_MAST_LOST_ARB 0x38
50#define MV64x60_I2C_STATUS_MAST_RD_ADDR_ACK 0x40
51#define MV64x60_I2C_STATUS_MAST_RD_ADDR_NO_ACK 0x48
52#define MV64x60_I2C_STATUS_MAST_RD_DATA_ACK 0x50
53#define MV64x60_I2C_STATUS_MAST_RD_DATA_NO_ACK 0x58
54#define MV64x60_I2C_STATUS_MAST_WR_ADDR_2_ACK 0xd0
55#define MV64x60_I2C_STATUS_MAST_WR_ADDR_2_NO_ACK 0xd8
56#define MV64x60_I2C_STATUS_MAST_RD_ADDR_2_ACK 0xe0
57#define MV64x60_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK 0xe8
58#define MV64x60_I2C_STATUS_NO_STATUS 0xf8
59
60static u8 *ctlr_base;
61
62static int mv64x60_i2c_wait_for_status(int wanted)
63{
64 int i;
65 int status;
66
67 for (i=0; i<1000; i++) {
68 udelay(10);
69 status = in_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_STATUS))
70 & 0xff;
71 if (status == wanted)
72 return status;
73 }
74 return -status;
75}
76
77static int mv64x60_i2c_control(int control, int status)
78{
79 out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);
80 return mv64x60_i2c_wait_for_status(status);
81}
82
83static int mv64x60_i2c_read_byte(int control, int status)
84{
85 out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);
86 if (mv64x60_i2c_wait_for_status(status) < 0)
87 return -1;
88 return in_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_DATA)) & 0xff;
89}
90
91static int mv64x60_i2c_write_byte(int data, int control, int status)
92{
93 out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_DATA), data & 0xff);
94 out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);
95 return mv64x60_i2c_wait_for_status(status);
96}
97
98int mv64x60_i2c_read(u32 devaddr, u8 *buf, u32 offset, u32 offset_size,
99 u32 count)
100{
101 int i;
102 int data;
103 int control;
104 int status;
105
106 if (ctlr_base == NULL)
107 return -1;
108
109 /* send reset */
110 out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_SOFT_RESET), 0);
111 out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_SLAVE_ADDR), 0);
112 out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_EXT_SLAVE_ADDR), 0);
113 out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_BAUD), (4 << 3) | 0x4);
114
115 if (mv64x60_i2c_control(MV64x60_I2C_CONTROL_TWSIEN,
116 MV64x60_I2C_STATUS_NO_STATUS) < 0)
117 return -1;
118
119 /* send start */
120 control = MV64x60_I2C_CONTROL_START | MV64x60_I2C_CONTROL_TWSIEN;
121 status = MV64x60_I2C_STATUS_MAST_START;
122 if (mv64x60_i2c_control(control, status) < 0)
123 return -1;
124
125 /* select device for writing */
126 data = devaddr & ~0x1;
127 control = MV64x60_I2C_CONTROL_TWSIEN;
128 status = MV64x60_I2C_STATUS_MAST_WR_ADDR_ACK;
129 if (mv64x60_i2c_write_byte(data, control, status) < 0)
130 return -1;
131
132 /* send offset of data */
133 control = MV64x60_I2C_CONTROL_TWSIEN;
134 status = MV64x60_I2C_STATUS_MAST_WR_ACK;
135 if (offset_size > 1) {
136 if (mv64x60_i2c_write_byte(offset >> 8, control, status) < 0)
137 return -1;
138 }
139 if (mv64x60_i2c_write_byte(offset, control, status) < 0)
140 return -1;
141
142 /* resend start */
143 control = MV64x60_I2C_CONTROL_START | MV64x60_I2C_CONTROL_TWSIEN;
144 status = MV64x60_I2C_STATUS_MAST_REPEAT_START;
145 if (mv64x60_i2c_control(control, status) < 0)
146 return -1;
147
148 /* select device for reading */
149 data = devaddr | 0x1;
150 control = MV64x60_I2C_CONTROL_TWSIEN;
151 status = MV64x60_I2C_STATUS_MAST_RD_ADDR_ACK;
152 if (mv64x60_i2c_write_byte(data, control, status) < 0)
153 return -1;
154
155 /* read all but last byte of data */
156 control = MV64x60_I2C_CONTROL_ACK | MV64x60_I2C_CONTROL_TWSIEN;
157 status = MV64x60_I2C_STATUS_MAST_RD_DATA_ACK;
158
159 for (i=1; i<count; i++) {
160 data = mv64x60_i2c_read_byte(control, status);
161 if (data < 0) {
162 printf("errors on iteration %d\n", i);
163 return -1;
164 }
165 *buf++ = data;
166 }
167
168 /* read last byte of data */
169 control = MV64x60_I2C_CONTROL_TWSIEN;
170 status = MV64x60_I2C_STATUS_MAST_RD_DATA_NO_ACK;
171 data = mv64x60_i2c_read_byte(control, status);
172 if (data < 0)
173 return -1;
174 *buf++ = data;
175
176 /* send stop */
177 control = MV64x60_I2C_CONTROL_STOP | MV64x60_I2C_CONTROL_TWSIEN;
178 status = MV64x60_I2C_STATUS_NO_STATUS;
179 if (mv64x60_i2c_control(control, status) < 0)
180 return -1;
181
182 return count;
183}
184
185int mv64x60_i2c_open(void)
186{
187 u32 v;
188 void *devp;
189
190 devp = finddevice("/mv64x60/i2c");
191 if (devp == NULL)
192 goto err_out;
193 if (getprop(devp, "virtual-reg", &v, sizeof(v)) != sizeof(v))
194 goto err_out;
195
196 ctlr_base = (u8 *)v;
197 return 0;
198
199err_out:
200 return -1;
201}
202
203void mv64x60_i2c_close(void)
204{
205 ctlr_base = NULL;
206}