1 /*
2 * (C) Copyright 2009
3 * Frank Bodammer <frank.bodammer@gcd-solutions.de>
4 * (C) Copyright 2009 Semihalf, Grzegorz Bernacki
5 *
6 * See file CREDITS for list of people who contributed to this
7 * project.
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of
12 * the License, or (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
22 * MA 02111-1307 USA
23 */
24
25 #include <common.h>
26 #include <asm/io.h>
27 #include <malloc.h>
28 #include <spi.h>
29 #include <mpc5xxx.h>
30
spi_init(void)31 void spi_init(void)
32 {
33 struct mpc5xxx_spi *spi = (struct mpc5xxx_spi *)MPC5XXX_SPI;
34 /*
35 * Its important to use the correct order when initializing the
36 * registers
37 */
38 out_8(&spi->ddr, 0x0F); /* set all SPI pins as output */
39 out_8(&spi->pdr, 0x00); /* set SS low */
40 /* SPI is master, SS is general purpose output */
41 out_8(&spi->cr1, SPI_CR_MSTR | SPI_CR_SPE);
42 out_8(&spi->cr2, 0x00); /* normal operation */
43 out_8(&spi->brr, 0x77); /* baud rate: IPB clock / 2048 */
44 }
45
spi_setup_slave(unsigned int bus,unsigned int cs,unsigned int max_hz,unsigned int mode)46 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
47 unsigned int max_hz, unsigned int mode)
48 {
49 struct spi_slave *slave;
50
51 slave = malloc(sizeof(struct spi_slave));
52 if (!slave)
53 return NULL;
54
55 slave->bus = bus;
56 slave->cs = cs;
57
58 return slave;
59 }
60
spi_free_slave(struct spi_slave * slave)61 void spi_free_slave(struct spi_slave *slave)
62 {
63 free(slave);
64 }
65
spi_claim_bus(struct spi_slave * slave)66 int spi_claim_bus(struct spi_slave *slave)
67 {
68 return 0;
69 }
70
spi_release_bus(struct spi_slave * slave)71 void spi_release_bus(struct spi_slave *slave)
72 {
73 return;
74 }
75
spi_xfer(struct spi_slave * slave,unsigned int bitlen,const void * dout,void * din,unsigned long flags)76 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
77 void *din, unsigned long flags)
78 {
79 struct mpc5xxx_spi *spi = (struct mpc5xxx_spi *)MPC5XXX_SPI;
80 int i, iter = bitlen >> 3;
81 const uchar *txp = dout;
82 uchar *rxp = din;
83
84 debug("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
85 slave->bus, slave->cs, *(uint *) dout, *(uint *) din, bitlen);
86
87 if (flags & SPI_XFER_BEGIN)
88 setbits_8(&spi->pdr, SPI_PDR_SS);
89
90 for (i = 0; i < iter; i++) {
91 udelay(1000);
92 debug("spi_xfer: sending %x\n", txp[i]);
93 out_8(&spi->dr, txp[i]);
94 while (!(in_8(&spi->sr) & SPI_SR_SPIF)) {
95 udelay(1000);
96 if (in_8(&spi->sr) & SPI_SR_WCOL) {
97 rxp[i] = in_8(&spi->dr);
98 puts("spi_xfer: write collision\n");
99 return -1;
100 }
101 }
102 rxp[i] = in_8(&spi->dr);
103 debug("spi_xfer: received %x\n", rxp[i]);
104 }
105 if (flags & SPI_XFER_END)
106 clrbits_8(&spi->pdr, SPI_PDR_SS);
107
108 return 0;
109 }
110