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27#include <common.h>
28#include <spi.h>
29
30#include <malloc.h>
31
32
33
34
35
36#ifdef DEBUG_SPI
37#define PRINTD(fmt,args...) printf (fmt ,##args)
38#else
39#define PRINTD(fmt,args...)
40#endif
41
42struct soft_spi_slave {
43 struct spi_slave slave;
44 unsigned int mode;
45};
46
47static inline struct soft_spi_slave *to_soft_spi(struct spi_slave *slave)
48{
49 return container_of(slave, struct soft_spi_slave, slave);
50}
51
52
53
54
55
56
57
58
59void spi_init (void)
60{
61#ifdef SPI_INIT
62 volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
63
64 SPI_INIT;
65#endif
66}
67
68struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
69 unsigned int max_hz, unsigned int mode)
70{
71 struct soft_spi_slave *ss;
72
73 if (!spi_cs_is_valid(bus, cs))
74 return NULL;
75
76 ss = malloc(sizeof(struct soft_spi_slave));
77 if (!ss)
78 return NULL;
79
80 ss->slave.bus = bus;
81 ss->slave.cs = cs;
82 ss->mode = mode;
83
84
85
86 return &ss->slave;
87}
88
89void spi_free_slave(struct spi_slave *slave)
90{
91 struct soft_spi_slave *ss = to_soft_spi(slave);
92
93 free(ss);
94}
95
96int spi_claim_bus(struct spi_slave *slave)
97{
98#ifdef CONFIG_SYS_IMMR
99 volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
100#endif
101 struct soft_spi_slave *ss = to_soft_spi(slave);
102
103
104
105
106
107 if (ss->mode & SPI_CPOL)
108 SPI_SCL(1);
109 else
110 SPI_SCL(0);
111
112 return 0;
113}
114
115void spi_release_bus(struct spi_slave *slave)
116{
117
118}
119
120
121
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130
131
132int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
133 const void *dout, void *din, unsigned long flags)
134{
135#ifdef CONFIG_SYS_IMMR
136 volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
137#endif
138 struct soft_spi_slave *ss = to_soft_spi(slave);
139 uchar tmpdin = 0;
140 uchar tmpdout = 0;
141 const u8 *txd = dout;
142 u8 *rxd = din;
143 int cpol = ss->mode & SPI_CPOL;
144 int cpha = ss->mode & SPI_CPHA;
145 unsigned int j;
146
147 PRINTD("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
148 slave->bus, slave->cs, *(uint *)txd, *(uint *)rxd, bitlen);
149
150 if (flags & SPI_XFER_BEGIN)
151 spi_cs_activate(slave);
152
153 for(j = 0; j < bitlen; j++) {
154
155
156
157 if((j % 8) == 0) {
158 tmpdout = *txd++;
159 if(j != 0) {
160 *rxd++ = tmpdin;
161 }
162 tmpdin = 0;
163 }
164
165 if (!cpha)
166 SPI_SCL(!cpol);
167 SPI_SDA(tmpdout & 0x80);
168 SPI_DELAY;
169 if (cpha)
170 SPI_SCL(!cpol);
171 else
172 SPI_SCL(cpol);
173 tmpdin <<= 1;
174 tmpdin |= SPI_READ;
175 tmpdout <<= 1;
176 SPI_DELAY;
177 if (cpha)
178 SPI_SCL(cpol);
179 }
180
181
182
183
184
185 if((bitlen % 8) != 0)
186 tmpdin <<= 8 - (bitlen % 8);
187 *rxd++ = tmpdin;
188
189 if (flags & SPI_XFER_END)
190 spi_cs_deactivate(slave);
191
192 return(0);
193}
194