]>
git.ipfire.org Git - people/ms/u-boot.git/blob - drivers/spi/sh_spi.c
4 * Copyright (C) 2011-2012 Renesas Solutions Corp.
6 * SPDX-License-Identifier: GPL-2.0
16 static void sh_spi_write(unsigned long data
, unsigned long *reg
)
21 static unsigned long sh_spi_read(unsigned long *reg
)
26 static void sh_spi_set_bit(unsigned long val
, unsigned long *reg
)
30 tmp
= sh_spi_read(reg
);
32 sh_spi_write(tmp
, reg
);
35 static void sh_spi_clear_bit(unsigned long val
, unsigned long *reg
)
39 tmp
= sh_spi_read(reg
);
41 sh_spi_write(tmp
, reg
);
44 static void clear_fifo(struct sh_spi
*ss
)
46 sh_spi_set_bit(SH_SPI_RSTF
, &ss
->regs
->cr2
);
47 sh_spi_clear_bit(SH_SPI_RSTF
, &ss
->regs
->cr2
);
50 static int recvbuf_wait(struct sh_spi
*ss
)
52 while (sh_spi_read(&ss
->regs
->cr1
) & SH_SPI_RBE
) {
60 static int write_fifo_empty_wait(struct sh_spi
*ss
)
62 while (!(sh_spi_read(&ss
->regs
->cr1
) & SH_SPI_TBE
)) {
74 static void sh_spi_set_cs(struct sh_spi
*ss
, unsigned int cs
)
76 unsigned long val
= 0;
83 sh_spi_clear_bit(SH_SPI_SSS0
| SH_SPI_SSS1
, &ss
->regs
->cr4
);
84 sh_spi_set_bit(val
, &ss
->regs
->cr4
);
87 struct spi_slave
*spi_setup_slave(unsigned int bus
, unsigned int cs
,
88 unsigned int max_hz
, unsigned int mode
)
92 if (!spi_cs_is_valid(bus
, cs
))
95 ss
= spi_alloc_slave(struct sh_spi
, bus
, cs
);
99 ss
->regs
= (struct sh_spi_regs
*)CONFIG_SH_SPI_BASE
;
102 sh_spi_write(0xfe, &ss
->regs
->cr1
);
104 sh_spi_write(0x00, &ss
->regs
->cr1
);
106 sh_spi_write(0x00, &ss
->regs
->cr3
);
107 sh_spi_set_cs(ss
, cs
);
112 sh_spi_write(sh_spi_read(&ss
->regs
->cr2
) | 0x07, &ss
->regs
->cr2
);
118 void spi_free_slave(struct spi_slave
*slave
)
120 struct sh_spi
*spi
= to_sh_spi(slave
);
125 int spi_claim_bus(struct spi_slave
*slave
)
130 void spi_release_bus(struct spi_slave
*slave
)
132 struct sh_spi
*ss
= to_sh_spi(slave
);
134 sh_spi_write(sh_spi_read(&ss
->regs
->cr1
) &
135 ~(SH_SPI_SSA
| SH_SPI_SSDB
| SH_SPI_SSD
), &ss
->regs
->cr1
);
138 static int sh_spi_send(struct sh_spi
*ss
, const unsigned char *tx_data
,
139 unsigned int len
, unsigned long flags
)
141 int i
, cur_len
, ret
= 0;
142 int remain
= (int)len
;
144 if (len
>= SH_SPI_FIFO_SIZE
)
145 sh_spi_set_bit(SH_SPI_SSA
, &ss
->regs
->cr1
);
148 cur_len
= (remain
< SH_SPI_FIFO_SIZE
) ?
149 remain
: SH_SPI_FIFO_SIZE
;
150 for (i
= 0; i
< cur_len
&&
151 !(sh_spi_read(&ss
->regs
->cr4
) & SH_SPI_WPABRT
) &&
152 !(sh_spi_read(&ss
->regs
->cr1
) & SH_SPI_TBF
);
154 sh_spi_write(tx_data
[i
], &ss
->regs
->tbr_rbr
);
158 if (sh_spi_read(&ss
->regs
->cr4
) & SH_SPI_WPABRT
) {
159 /* Abort the transaction */
160 flags
|= SPI_XFER_END
;
161 sh_spi_set_bit(SH_SPI_WPABRT
, &ss
->regs
->cr4
);
170 write_fifo_empty_wait(ss
);
173 if (flags
& SPI_XFER_END
) {
174 sh_spi_clear_bit(SH_SPI_SSD
| SH_SPI_SSDB
, &ss
->regs
->cr1
);
175 sh_spi_set_bit(SH_SPI_SSA
, &ss
->regs
->cr1
);
177 write_fifo_empty_wait(ss
);
183 static int sh_spi_receive(struct sh_spi
*ss
, unsigned char *rx_data
,
184 unsigned int len
, unsigned long flags
)
188 if (len
> SH_SPI_MAX_BYTE
)
189 sh_spi_write(SH_SPI_MAX_BYTE
, &ss
->regs
->cr3
);
191 sh_spi_write(len
, &ss
->regs
->cr3
);
193 sh_spi_clear_bit(SH_SPI_SSD
| SH_SPI_SSDB
, &ss
->regs
->cr1
);
194 sh_spi_set_bit(SH_SPI_SSA
, &ss
->regs
->cr1
);
196 for (i
= 0; i
< len
; i
++) {
197 if (recvbuf_wait(ss
))
200 rx_data
[i
] = (unsigned char)sh_spi_read(&ss
->regs
->tbr_rbr
);
202 sh_spi_write(0, &ss
->regs
->cr3
);
207 int spi_xfer(struct spi_slave
*slave
, unsigned int bitlen
, const void *dout
,
208 void *din
, unsigned long flags
)
210 struct sh_spi
*ss
= to_sh_spi(slave
);
211 const unsigned char *tx_data
= dout
;
212 unsigned char *rx_data
= din
;
213 unsigned int len
= bitlen
/ 8;
216 if (flags
& SPI_XFER_BEGIN
)
217 sh_spi_write(sh_spi_read(&ss
->regs
->cr1
) & ~SH_SPI_SSA
,
221 ret
= sh_spi_send(ss
, tx_data
, len
, flags
);
223 if (ret
== 0 && rx_data
)
224 ret
= sh_spi_receive(ss
, rx_data
, len
, flags
);
226 if (flags
& SPI_XFER_END
) {
227 sh_spi_set_bit(SH_SPI_SSD
, &ss
->regs
->cr1
);
230 sh_spi_clear_bit(SH_SPI_SSA
| SH_SPI_SSDB
| SH_SPI_SSD
,
238 int spi_cs_is_valid(unsigned int bus
, unsigned int cs
)
240 if (!bus
&& cs
< SH_SPI_NUM_CS
)
246 void spi_cs_activate(struct spi_slave
*slave
)
251 void spi_cs_deactivate(struct spi_slave
*slave
)