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git.ipfire.org Git - thirdparty/u-boot.git/blob - drivers/spi/sh_spi.c
1 // SPDX-License-Identifier: GPL-2.0
5 * Copyright (C) 2011-2012 Renesas Solutions Corp.
15 static void sh_spi_write(unsigned long data
, unsigned long *reg
)
20 static unsigned long sh_spi_read(unsigned long *reg
)
25 static void sh_spi_set_bit(unsigned long val
, unsigned long *reg
)
29 tmp
= sh_spi_read(reg
);
31 sh_spi_write(tmp
, reg
);
34 static void sh_spi_clear_bit(unsigned long val
, unsigned long *reg
)
38 tmp
= sh_spi_read(reg
);
40 sh_spi_write(tmp
, reg
);
43 static void clear_fifo(struct sh_spi
*ss
)
45 sh_spi_set_bit(SH_SPI_RSTF
, &ss
->regs
->cr2
);
46 sh_spi_clear_bit(SH_SPI_RSTF
, &ss
->regs
->cr2
);
49 static int recvbuf_wait(struct sh_spi
*ss
)
51 while (sh_spi_read(&ss
->regs
->cr1
) & SH_SPI_RBE
) {
59 static int write_fifo_empty_wait(struct sh_spi
*ss
)
61 while (!(sh_spi_read(&ss
->regs
->cr1
) & SH_SPI_TBE
)) {
73 static void sh_spi_set_cs(struct sh_spi
*ss
, unsigned int cs
)
75 unsigned long val
= 0;
82 sh_spi_clear_bit(SH_SPI_SSS0
| SH_SPI_SSS1
, &ss
->regs
->cr4
);
83 sh_spi_set_bit(val
, &ss
->regs
->cr4
);
86 struct spi_slave
*spi_setup_slave(unsigned int bus
, unsigned int cs
,
87 unsigned int max_hz
, unsigned int mode
)
91 if (!spi_cs_is_valid(bus
, cs
))
94 ss
= spi_alloc_slave(struct sh_spi
, bus
, cs
);
98 ss
->regs
= (struct sh_spi_regs
*)CONFIG_SH_SPI_BASE
;
101 sh_spi_write(0xfe, &ss
->regs
->cr1
);
103 sh_spi_write(0x00, &ss
->regs
->cr1
);
105 sh_spi_write(0x00, &ss
->regs
->cr3
);
106 sh_spi_set_cs(ss
, cs
);
111 sh_spi_write(sh_spi_read(&ss
->regs
->cr2
) | 0x07, &ss
->regs
->cr2
);
117 void spi_free_slave(struct spi_slave
*slave
)
119 struct sh_spi
*spi
= to_sh_spi(slave
);
124 int spi_claim_bus(struct spi_slave
*slave
)
129 void spi_release_bus(struct spi_slave
*slave
)
131 struct sh_spi
*ss
= to_sh_spi(slave
);
133 sh_spi_write(sh_spi_read(&ss
->regs
->cr1
) &
134 ~(SH_SPI_SSA
| SH_SPI_SSDB
| SH_SPI_SSD
), &ss
->regs
->cr1
);
137 static int sh_spi_send(struct sh_spi
*ss
, const unsigned char *tx_data
,
138 unsigned int len
, unsigned long flags
)
140 int i
, cur_len
, ret
= 0;
141 int remain
= (int)len
;
143 if (len
>= SH_SPI_FIFO_SIZE
)
144 sh_spi_set_bit(SH_SPI_SSA
, &ss
->regs
->cr1
);
147 cur_len
= (remain
< SH_SPI_FIFO_SIZE
) ?
148 remain
: SH_SPI_FIFO_SIZE
;
149 for (i
= 0; i
< cur_len
&&
150 !(sh_spi_read(&ss
->regs
->cr4
) & SH_SPI_WPABRT
) &&
151 !(sh_spi_read(&ss
->regs
->cr1
) & SH_SPI_TBF
);
153 sh_spi_write(tx_data
[i
], &ss
->regs
->tbr_rbr
);
157 if (sh_spi_read(&ss
->regs
->cr4
) & SH_SPI_WPABRT
) {
158 /* Abort the transaction */
159 flags
|= SPI_XFER_END
;
160 sh_spi_set_bit(SH_SPI_WPABRT
, &ss
->regs
->cr4
);
169 write_fifo_empty_wait(ss
);
172 if (flags
& SPI_XFER_END
) {
173 sh_spi_clear_bit(SH_SPI_SSD
| SH_SPI_SSDB
, &ss
->regs
->cr1
);
174 sh_spi_set_bit(SH_SPI_SSA
, &ss
->regs
->cr1
);
176 write_fifo_empty_wait(ss
);
182 static int sh_spi_receive(struct sh_spi
*ss
, unsigned char *rx_data
,
183 unsigned int len
, unsigned long flags
)
187 if (len
> SH_SPI_MAX_BYTE
)
188 sh_spi_write(SH_SPI_MAX_BYTE
, &ss
->regs
->cr3
);
190 sh_spi_write(len
, &ss
->regs
->cr3
);
192 sh_spi_clear_bit(SH_SPI_SSD
| SH_SPI_SSDB
, &ss
->regs
->cr1
);
193 sh_spi_set_bit(SH_SPI_SSA
, &ss
->regs
->cr1
);
195 for (i
= 0; i
< len
; i
++) {
196 if (recvbuf_wait(ss
))
199 rx_data
[i
] = (unsigned char)sh_spi_read(&ss
->regs
->tbr_rbr
);
201 sh_spi_write(0, &ss
->regs
->cr3
);
206 int spi_xfer(struct spi_slave
*slave
, unsigned int bitlen
, const void *dout
,
207 void *din
, unsigned long flags
)
209 struct sh_spi
*ss
= to_sh_spi(slave
);
210 const unsigned char *tx_data
= dout
;
211 unsigned char *rx_data
= din
;
212 unsigned int len
= bitlen
/ 8;
215 if (flags
& SPI_XFER_BEGIN
)
216 sh_spi_write(sh_spi_read(&ss
->regs
->cr1
) & ~SH_SPI_SSA
,
220 ret
= sh_spi_send(ss
, tx_data
, len
, flags
);
222 if (ret
== 0 && rx_data
)
223 ret
= sh_spi_receive(ss
, rx_data
, len
, flags
);
225 if (flags
& SPI_XFER_END
) {
226 sh_spi_set_bit(SH_SPI_SSD
, &ss
->regs
->cr1
);
229 sh_spi_clear_bit(SH_SPI_SSA
| SH_SPI_SSDB
| SH_SPI_SSD
,
237 int spi_cs_is_valid(unsigned int bus
, unsigned int cs
)
239 if (!bus
&& cs
< SH_SPI_NUM_CS
)
245 void spi_cs_activate(struct spi_slave
*slave
)
250 void spi_cs_deactivate(struct spi_slave
*slave
)