This source file includes following definitions.
- mb862xx_i2c_wait_event
- mb862xx_i2c_do_address
- mb862xx_i2c_write_byte
- mb862xx_i2c_read_byte
- mb862xx_i2c_stop
- mb862xx_i2c_read
- mb862xx_i2c_write
- mb862xx_xfer
- mb862xx_func
- mb862xx_i2c_init
- mb862xx_i2c_exit
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8 #include <linux/fb.h>
9 #include <linux/i2c.h>
10 #include <linux/io.h>
11 #include <linux/delay.h>
12 #include <linux/export.h>
13
14 #include "mb862xxfb.h"
15 #include "mb862xx_reg.h"
16
17 static int mb862xx_i2c_wait_event(struct i2c_adapter *adap)
18 {
19 struct mb862xxfb_par *par = adap->algo_data;
20 u32 reg;
21
22 do {
23 udelay(10);
24 reg = inreg(i2c, GC_I2C_BCR);
25 if (reg & (I2C_INT | I2C_BER))
26 break;
27 } while (1);
28
29 return (reg & I2C_BER) ? 0 : 1;
30 }
31
32 static int mb862xx_i2c_do_address(struct i2c_adapter *adap, int addr)
33 {
34 struct mb862xxfb_par *par = adap->algo_data;
35
36 outreg(i2c, GC_I2C_DAR, addr);
37 outreg(i2c, GC_I2C_CCR, I2C_CLOCK_AND_ENABLE);
38 outreg(i2c, GC_I2C_BCR, par->i2c_rs ? I2C_REPEATED_START : I2C_START);
39 if (!mb862xx_i2c_wait_event(adap))
40 return -EIO;
41 par->i2c_rs = !(inreg(i2c, GC_I2C_BSR) & I2C_LRB);
42 return par->i2c_rs;
43 }
44
45 static int mb862xx_i2c_write_byte(struct i2c_adapter *adap, u8 byte)
46 {
47 struct mb862xxfb_par *par = adap->algo_data;
48
49 outreg(i2c, GC_I2C_DAR, byte);
50 outreg(i2c, GC_I2C_BCR, I2C_START);
51 if (!mb862xx_i2c_wait_event(adap))
52 return -EIO;
53 return !(inreg(i2c, GC_I2C_BSR) & I2C_LRB);
54 }
55
56 static int mb862xx_i2c_read_byte(struct i2c_adapter *adap, u8 *byte, int last)
57 {
58 struct mb862xxfb_par *par = adap->algo_data;
59
60 outreg(i2c, GC_I2C_BCR, I2C_START | (last ? 0 : I2C_ACK));
61 if (!mb862xx_i2c_wait_event(adap))
62 return 0;
63 *byte = inreg(i2c, GC_I2C_DAR);
64 return 1;
65 }
66
67 static void mb862xx_i2c_stop(struct i2c_adapter *adap)
68 {
69 struct mb862xxfb_par *par = adap->algo_data;
70
71 outreg(i2c, GC_I2C_BCR, I2C_STOP);
72 outreg(i2c, GC_I2C_CCR, I2C_DISABLE);
73 par->i2c_rs = 0;
74 }
75
76 static int mb862xx_i2c_read(struct i2c_adapter *adap, struct i2c_msg *m)
77 {
78 int i, ret = 0;
79 int last = m->len - 1;
80
81 for (i = 0; i < m->len; i++) {
82 if (!mb862xx_i2c_read_byte(adap, &m->buf[i], i == last)) {
83 ret = -EIO;
84 break;
85 }
86 }
87 return ret;
88 }
89
90 static int mb862xx_i2c_write(struct i2c_adapter *adap, struct i2c_msg *m)
91 {
92 int i, ret = 0;
93
94 for (i = 0; i < m->len; i++) {
95 if (!mb862xx_i2c_write_byte(adap, m->buf[i])) {
96 ret = -EIO;
97 break;
98 }
99 }
100 return ret;
101 }
102
103 static int mb862xx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
104 int num)
105 {
106 struct mb862xxfb_par *par = adap->algo_data;
107 struct i2c_msg *m;
108 int addr;
109 int i = 0, err = 0;
110
111 dev_dbg(par->dev, "%s: %d msgs\n", __func__, num);
112
113 for (i = 0; i < num; i++) {
114 m = &msgs[i];
115 if (!m->len) {
116 dev_dbg(par->dev, "%s: null msgs\n", __func__);
117 continue;
118 }
119 addr = m->addr;
120 if (m->flags & I2C_M_RD)
121 addr |= 1;
122
123 err = mb862xx_i2c_do_address(adap, addr);
124 if (err < 0)
125 break;
126 if (m->flags & I2C_M_RD)
127 err = mb862xx_i2c_read(adap, m);
128 else
129 err = mb862xx_i2c_write(adap, m);
130 }
131
132 if (i)
133 mb862xx_i2c_stop(adap);
134
135 return (err < 0) ? err : i;
136 }
137
138 static u32 mb862xx_func(struct i2c_adapter *adap)
139 {
140 return I2C_FUNC_SMBUS_BYTE_DATA;
141 }
142
143 static const struct i2c_algorithm mb862xx_algo = {
144 .master_xfer = mb862xx_xfer,
145 .functionality = mb862xx_func,
146 };
147
148 static struct i2c_adapter mb862xx_i2c_adapter = {
149 .name = "MB862xx I2C adapter",
150 .algo = &mb862xx_algo,
151 .owner = THIS_MODULE,
152 };
153
154 int mb862xx_i2c_init(struct mb862xxfb_par *par)
155 {
156 mb862xx_i2c_adapter.algo_data = par;
157 par->adap = &mb862xx_i2c_adapter;
158
159 return i2c_add_adapter(par->adap);
160 }
161
162 void mb862xx_i2c_exit(struct mb862xxfb_par *par)
163 {
164 if (par->adap) {
165 i2c_del_adapter(par->adap);
166 par->adap = NULL;
167 }
168 }