common/cmd_spi.c

   1 /*
   2  * (C) Copyright 2002
   3  * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 /*
  25  * SPI Read/Write Utilities
  26  */
  27
  28 #include <common.h>
  29 #include <command.h>
  30 #include <spi.h>
  31
  32 /*-----------------------------------------------------------------------
  33  * Definitions
  34  */
  35
  36 #ifndef MAX_SPI_BYTES
  37 #   define MAX_SPI_BYTES 32     /* Maximum number of bytes we can handle */
  38 #endif
  39
  40 #ifndef CONFIG_DEFAULT_SPI_BUS
  41 #   define CONFIG_DEFAULT_SPI_BUS       0
  42 #endif
  43 #ifndef CONFIG_DEFAULT_SPI_MODE
  44 #   define CONFIG_DEFAULT_SPI_MODE      SPI_MODE_0
  45 #endif
  46
  47 /*
  48  * Values from last command.
  49  */
  50 static unsigned int     device;
  51 static int              bitlen;
  52 static uchar            dout[MAX_SPI_BYTES];
  53 static uchar            din[MAX_SPI_BYTES];
  54
  55 /*
  56  * SPI read/write
  57  *
  58  * Syntax:
  59  *   spi {dev} {num_bits} {dout}
  60  *     {dev} is the device number for controlling chip select (see TBD)
  61  *     {num_bits} is the number of bits to send & receive (base 10)
  62  *     {dout} is a hexadecimal string of data to send
  63  * The command prints out the hexadecimal string received via SPI.
  64  */
  65
  66 int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
  67 {
  68         struct spi_slave *slave;
  69         char  *cp = 0;
  70         uchar tmp;
  71         int   j;
  72         int   rcode = 0;
  73
  74         /*
  75          * We use the last specified parameters, unless new ones are
  76          * entered.
  77          */
  78
  79         if ((flag & CMD_FLAG_REPEAT) == 0)
  80         {
  81                 if (argc >= 2)
  82                         device = simple_strtoul(argv[1], NULL, 10);
  83                 if (argc >= 3)
  84                         bitlen = simple_strtoul(argv[2], NULL, 10);
  85                 if (argc >= 4) {
  86                         cp = argv[3];
  87                         for(j = 0; *cp; j++, cp++) {
  88                                 tmp = *cp - '0';
  89                                 if(tmp > 9)
  90                                         tmp -= ('A' - '0') - 10;
  91                                 if(tmp > 15)
  92                                         tmp -= ('a' - 'A');
  93                                 if(tmp > 15) {
  94                                         printf("Hex conversion error on %c, giving up.\n", *cp);
  95                                         return 1;
  96                                 }
  97                                 if((j % 2) == 0)
  98                                         dout[j / 2] = (tmp << 4);
  99                                 else
 100                                         dout[j / 2] |= tmp;
 101                         }
 102                 }
 103         }
 104
 105         if ((bitlen < 0) || (bitlen >  (MAX_SPI_BYTES * 8))) {
 106                 printf("Invalid bitlen %d, giving up.\n", bitlen);
 107                 return 1;
 108         }
 109
 110         /* FIXME: Make these parameters run-time configurable */
 111         slave = spi_setup_slave(CONFIG_DEFAULT_SPI_BUS, device, 1000000,
 112                         CONFIG_DEFAULT_SPI_MODE);
 113         if (!slave) {
 114                 printf("Invalid device %d, giving up.\n", device);
 115                 return 1;
 116         }
 117
 118         debug ("spi chipsel = %08X\n", device);
 119
 120         spi_claim_bus(slave);
 121         if(spi_xfer(slave, bitlen, dout, din,
 122                                 SPI_XFER_BEGIN | SPI_XFER_END) != 0) {
 123                 printf("Error with the SPI transaction.\n");
 124                 rcode = 1;
 125         } else {
 126                 for(j = 0; j < ((bitlen + 7) / 8); j++) {
 127                         printf("%02X", din[j]);
 128                 }
 129                 printf("\n");
 130         }
 131         spi_release_bus(slave);
 132         spi_free_slave(slave);
 133
 134         return rcode;
 135 }
 136
 137 /***************************************************/
 138
 139 U_BOOT_CMD(
 140         sspi,   5,      1,      do_spi,
 141         "SPI utility commands",
 142         "<device> <bit_len> <dout> - Send <bit_len> bits from <dout> out the SPI\n"
 143         "<device>  - Identifies the chip select of the device\n"
 144         "<bit_len> - Number of bits to send (base 10)\n"
 145         "<dout>    - Hexadecimal string that gets sent\n"
 146 );