1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
|
/*
* (C) Copyright 2009
* Frank Bodammer <frank.bodammer@gcd-solutions.de>
* (C) Copyright 2009 Semihalf, Grzegorz Bernacki
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <asm/io.h>
#include <malloc.h>
#include <spi.h>
#include <mpc5xxx.h>
void spi_init(void)
{
struct mpc5xxx_spi *spi = (struct mpc5xxx_spi *)MPC5XXX_SPI;
/*
* Its important to use the correct order when initializing the
* registers
*/
out_8(&spi->ddr, 0x0F); /* set all SPI pins as output */
out_8(&spi->pdr, 0x00); /* set SS low */
/* SPI is master, SS is general purpose output */
out_8(&spi->cr1, SPI_CR_MSTR | SPI_CR_SPE);
out_8(&spi->cr2, 0x00); /* normal operation */
out_8(&spi->brr, 0x77); /* baud rate: IPB clock / 2048 */
}
struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode)
{
struct spi_slave *slave;
slave = malloc(sizeof(struct spi_slave));
if (!slave)
return NULL;
slave->bus = bus;
slave->cs = cs;
return slave;
}
void spi_free_slave(struct spi_slave *slave)
{
free(slave);
}
int spi_claim_bus(struct spi_slave *slave)
{
return 0;
}
void spi_release_bus(struct spi_slave *slave)
{
return;
}
int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
void *din, unsigned long flags)
{
struct mpc5xxx_spi *spi = (struct mpc5xxx_spi *)MPC5XXX_SPI;
int i, iter = bitlen >> 3;
const uchar *txp = dout;
uchar *rxp = din;
debug("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
slave->bus, slave->cs, *(uint *) dout, *(uint *) din, bitlen);
if (flags & SPI_XFER_BEGIN)
setbits_8(&spi->pdr, SPI_PDR_SS);
for (i = 0; i < iter; i++) {
udelay(1000);
debug("spi_xfer: sending %x\n", txp[i]);
out_8(&spi->dr, txp[i]);
while (!(in_8(&spi->sr) & SPI_SR_SPIF)) {
udelay(1000);
if (in_8(&spi->sr) & SPI_SR_WCOL) {
rxp[i] = in_8(&spi->dr);
puts("spi_xfer: write collision\n");
return -1;
}
}
rxp[i] = in_8(&spi->dr);
debug("spi_xfer: received %x\n", rxp[i]);
}
if (flags & SPI_XFER_END)
clrbits_8(&spi->pdr, SPI_PDR_SS);
return 0;
}
|
