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26#include <common.h>
27#include <malloc.h>
28#include <spi.h>
29#include <asm/errno.h>
30#include <asm/io.h>
31#include <asm/arch/clock.h>
32#include <asm/arch/imx-regs.h>
33#include <asm/arch/sys_proto.h>
34
35#define MXS_SPI_MAX_TIMEOUT 1000000
36#define MXS_SPI_PORT_OFFSET 0x2000
37
38struct mxs_spi_slave {
39 struct spi_slave slave;
40 uint32_t max_khz;
41 uint32_t mode;
42 struct mx28_ssp_regs *regs;
43};
44
45static inline struct mxs_spi_slave *to_mxs_slave(struct spi_slave *slave)
46{
47 return container_of(slave, struct mxs_spi_slave, slave);
48}
49
50void spi_init(void)
51{
52}
53
54struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
55 unsigned int max_hz, unsigned int mode)
56{
57 struct mxs_spi_slave *mxs_slave;
58 uint32_t addr;
59
60 if (bus > 3) {
61 printf("MXS SPI: Max bus number is 3\n");
62 return NULL;
63 }
64
65 mxs_slave = malloc(sizeof(struct mxs_spi_slave));
66 if (!mxs_slave)
67 return NULL;
68
69 addr = MXS_SSP0_BASE + (bus * MXS_SPI_PORT_OFFSET);
70
71 mxs_slave->slave.bus = bus;
72 mxs_slave->slave.cs = cs;
73 mxs_slave->max_khz = max_hz / 1000;
74 mxs_slave->mode = mode;
75 mxs_slave->regs = (struct mx28_ssp_regs *)addr;
76
77 return &mxs_slave->slave;
78}
79
80void spi_free_slave(struct spi_slave *slave)
81{
82 struct mxs_spi_slave *mxs_slave = to_mxs_slave(slave);
83 free(mxs_slave);
84}
85
86int spi_claim_bus(struct spi_slave *slave)
87{
88 struct mxs_spi_slave *mxs_slave = to_mxs_slave(slave);
89 struct mx28_ssp_regs *ssp_regs = mxs_slave->regs;
90 uint32_t reg = 0;
91
92 mx28_reset_block(&ssp_regs->hw_ssp_ctrl0_reg);
93
94 writel(SSP_CTRL0_BUS_WIDTH_ONE_BIT, &ssp_regs->hw_ssp_ctrl0);
95
96 reg = SSP_CTRL1_SSP_MODE_SPI | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS;
97 reg |= (mxs_slave->mode & SPI_CPOL) ? SSP_CTRL1_POLARITY : 0;
98 reg |= (mxs_slave->mode & SPI_CPHA) ? SSP_CTRL1_PHASE : 0;
99 writel(reg, &ssp_regs->hw_ssp_ctrl1);
100
101 writel(0, &ssp_regs->hw_ssp_cmd0);
102
103 mx28_set_ssp_busclock(slave->bus, mxs_slave->max_khz);
104
105 return 0;
106}
107
108void spi_release_bus(struct spi_slave *slave)
109{
110}
111
112static void mxs_spi_start_xfer(struct mx28_ssp_regs *ssp_regs)
113{
114 writel(SSP_CTRL0_LOCK_CS, &ssp_regs->hw_ssp_ctrl0_set);
115 writel(SSP_CTRL0_IGNORE_CRC, &ssp_regs->hw_ssp_ctrl0_clr);
116}
117
118static void mxs_spi_end_xfer(struct mx28_ssp_regs *ssp_regs)
119{
120 writel(SSP_CTRL0_LOCK_CS, &ssp_regs->hw_ssp_ctrl0_clr);
121 writel(SSP_CTRL0_IGNORE_CRC, &ssp_regs->hw_ssp_ctrl0_set);
122}
123
124int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
125 const void *dout, void *din, unsigned long flags)
126{
127 struct mxs_spi_slave *mxs_slave = to_mxs_slave(slave);
128 struct mx28_ssp_regs *ssp_regs = mxs_slave->regs;
129 int len = bitlen / 8;
130 const char *tx = dout;
131 char *rx = din;
132 char dummy;
133
134 if (bitlen == 0) {
135 if (flags & SPI_XFER_END) {
136 rx = &dummy;
137 len = 1;
138 } else
139 return 0;
140 }
141
142 if (!rx && !tx)
143 return 0;
144
145 if (flags & SPI_XFER_BEGIN)
146 mxs_spi_start_xfer(ssp_regs);
147
148 while (len--) {
149
150 writel(1, &ssp_regs->hw_ssp_xfer_size);
151
152 if ((flags & SPI_XFER_END) && !len)
153 mxs_spi_end_xfer(ssp_regs);
154
155 if (tx)
156 writel(SSP_CTRL0_READ, &ssp_regs->hw_ssp_ctrl0_clr);
157 else
158 writel(SSP_CTRL0_READ, &ssp_regs->hw_ssp_ctrl0_set);
159
160 writel(SSP_CTRL0_RUN, &ssp_regs->hw_ssp_ctrl0_set);
161
162 if (mx28_wait_mask_set(&ssp_regs->hw_ssp_ctrl0_reg,
163 SSP_CTRL0_RUN, MXS_SPI_MAX_TIMEOUT)) {
164 printf("MXS SPI: Timeout waiting for start\n");
165 return -ETIMEDOUT;
166 }
167
168 if (tx)
169 writel(*tx++, &ssp_regs->hw_ssp_data);
170
171 writel(SSP_CTRL0_DATA_XFER, &ssp_regs->hw_ssp_ctrl0_set);
172
173 if (rx) {
174 if (mx28_wait_mask_clr(&ssp_regs->hw_ssp_status_reg,
175 SSP_STATUS_FIFO_EMPTY, MXS_SPI_MAX_TIMEOUT)) {
176 printf("MXS SPI: Timeout waiting for data\n");
177 return -ETIMEDOUT;
178 }
179
180 *rx = readl(&ssp_regs->hw_ssp_data);
181 rx++;
182 }
183
184 if (mx28_wait_mask_clr(&ssp_regs->hw_ssp_ctrl0_reg,
185 SSP_CTRL0_RUN, MXS_SPI_MAX_TIMEOUT)) {
186 printf("MXS SPI: Timeout waiting for finish\n");
187 return -ETIMEDOUT;
188 }
189 }
190
191 return 0;
192}
193
