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     bus;
  51 static unsigned int     cs;
  52 static unsigned int     mode;
  53 static int              bitlen;
  54 static uchar            dout[MAX_SPI_BYTES];
  55 static uchar            din[MAX_SPI_BYTES];
  56
  57 /*
  58  * SPI read/write
  59  *
  60  * Syntax:
  61  *   spi {dev} {num_bits} {dout}
  62  *     {dev} is the device number for controlling chip select (see TBD)
  63  *     {num_bits} is the number of bits to send & receive (base 10)
  64  *     {dout} is a hexadecimal string of data to send
  65  * The command prints out the hexadecimal string received via SPI.
  66  */
  67
  68 int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
  69 {
  70         struct spi_slave *slave;
  71         char  *cp = 0;
  72         uchar tmp;
  73         int   j;
  74         int   rcode = 0;
  75
  76         /*
  77          * We use the last specified parameters, unless new ones are
  78          * entered.
  79          */
  80
  81         if ((flag & CMD_FLAG_REPEAT) == 0)
  82         {
  83                 if (argc >= 2) {
  84                         mode = CONFIG_DEFAULT_SPI_MODE;
  85                         bus = simple_strtoul(argv[1], &cp, 10);
  86                         if (*cp == ':') {
  87                                 cs = simple_strtoul(cp+1, &cp, 10);
  88                         } else {
  89                                 cs = bus;
  90                                 bus = CONFIG_DEFAULT_SPI_BUS;
  91                         }
  92                         if (*cp == '.');
  93                                 mode = simple_strtoul(cp+1, NULL, 10);
  94                 }
  95                 if (argc >= 3)
  96                         bitlen = simple_strtoul(argv[2], NULL, 10);
  97                 if (argc >= 4) {
  98                         cp = argv[3];
  99                         for(j = 0; *cp; j++, cp++) {
 100                                 tmp = *cp - '0';
 101                                 if(tmp > 9)
 102                                         tmp -= ('A' - '0') - 10;
 103                                 if(tmp > 15)
 104                                         tmp -= ('a' - 'A');
 105                                 if(tmp > 15) {
 106                                         printf("Hex conversion error on %c\n", *cp);
 107                                         return 1;
 108                                 }
 109                                 if((j % 2) == 0)
 110                                         dout[j / 2] = (tmp << 4);
 111                                 else
 112                                         dout[j / 2] |= tmp;
 113                         }
 114                 }
 115         }
 116
 117         if ((bitlen < 0) || (bitlen >  (MAX_SPI_BYTES * 8))) {
 118                 printf("Invalid bitlen %d\n", bitlen);
 119                 return 1;
 120         }
 121
 122         slave = spi_setup_slave(bus, cs, 1000000, mode);
 123         if (!slave) {
 124                 printf("Invalid device %d:%d\n", bus, cs);
 125                 return 1;
 126         }
 127
 128         spi_claim_bus(slave);
 129         if(spi_xfer(slave, bitlen, dout, din,
 130                                 SPI_XFER_BEGIN | SPI_XFER_END) != 0) {
 131                 printf("Error during SPI transaction\n");
 132                 rcode = 1;
 133         } else {
 134                 for(j = 0; j < ((bitlen + 7) / 8); j++) {
 135                         printf("%02X", din[j]);
 136                 }
 137                 printf("\n");
 138         }
 139         spi_release_bus(slave);
 140         spi_free_slave(slave);
 141
 142         return rcode;
 143 }
 144
 145 /***************************************************/
 146
 147 U_BOOT_CMD(
 148         sspi,   5,      1,      do_spi,
 149         "SPI utility command",
 150         "[<bus>:]<cs>[.<mode>] <bit_len> <dout> - Send and receive bits\n"
 151         "<bus>     - Identifies the SPI bus\n"
 152         "<cs>      - Identifies the chip select\n"
 153         "<mode>    - Identifies the SPI mode to use\n"
 154         "<bit_len> - Number of bits to send (base 10)\n"
 155         "<dout>    - Hexadecimal string that gets sent"
 156 );