common/cmd_spi.c

   1 /*
   2  * (C) Copyright 2002
   3  * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 /*
   9  * SPI Read/Write Utilities
  10  */
  11
  12 #include <common.h>
  13 #include <command.h>
  14 #include <spi.h>
  15
  16 /*-----------------------------------------------------------------------
  17  * Definitions
  18  */
  19
  20 #ifndef MAX_SPI_BYTES
  21 #   define MAX_SPI_BYTES 32     /* Maximum number of bytes we can handle */
  22 #endif
  23
  24 #ifndef CONFIG_DEFAULT_SPI_BUS
  25 #   define CONFIG_DEFAULT_SPI_BUS       0
  26 #endif
  27 #ifndef CONFIG_DEFAULT_SPI_MODE
  28 #   define CONFIG_DEFAULT_SPI_MODE      SPI_MODE_0
  29 #endif
  30
  31 /*
  32  * Values from last command.
  33  */
  34 static unsigned int     bus;
  35 static unsigned int     cs;
  36 static unsigned int     mode;
  37 static int              bitlen;
  38 static uchar            dout[MAX_SPI_BYTES];
  39 static uchar            din[MAX_SPI_BYTES];
  40
  41 /*
  42  * SPI read/write
  43  *
  44  * Syntax:
  45  *   spi {dev} {num_bits} {dout}
  46  *     {dev} is the device number for controlling chip select (see TBD)
  47  *     {num_bits} is the number of bits to send & receive (base 10)
  48  *     {dout} is a hexadecimal string of data to send
  49  * The command prints out the hexadecimal string received via SPI.
  50  */
  51
  52 int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
  53 {
  54         struct spi_slave *slave;
  55         char  *cp = 0;
  56         uchar tmp;
  57         int   j;
  58         int   rcode = 0;
  59
  60         /*
  61          * We use the last specified parameters, unless new ones are
  62          * entered.
  63          */
  64
  65         if ((flag & CMD_FLAG_REPEAT) == 0)
  66         {
  67                 if (argc >= 2) {
  68                         mode = CONFIG_DEFAULT_SPI_MODE;
  69                         bus = simple_strtoul(argv[1], &cp, 10);
  70                         if (*cp == ':') {
  71                                 cs = simple_strtoul(cp+1, &cp, 10);
  72                         } else {
  73                                 cs = bus;
  74                                 bus = CONFIG_DEFAULT_SPI_BUS;
  75                         }
  76                         if (*cp == '.')
  77                                 mode = simple_strtoul(cp+1, NULL, 10);
  78                 }
  79                 if (argc >= 3)
  80                         bitlen = simple_strtoul(argv[2], NULL, 10);
  81                 if (argc >= 4) {
  82                         cp = argv[3];
  83                         for(j = 0; *cp; j++, cp++) {
  84                                 tmp = *cp - '0';
  85                                 if(tmp > 9)
  86                                         tmp -= ('A' - '0') - 10;
  87                                 if(tmp > 15)
  88                                         tmp -= ('a' - 'A');
  89                                 if(tmp > 15) {
  90                                         printf("Hex conversion error on %c\n", *cp);
  91                                         return 1;
  92                                 }
  93                                 if((j % 2) == 0)
  94                                         dout[j / 2] = (tmp << 4);
  95                                 else
  96                                         dout[j / 2] |= tmp;
  97                         }
  98                 }
  99         }
 100
 101         if ((bitlen < 0) || (bitlen >  (MAX_SPI_BYTES * 8))) {
 102                 printf("Invalid bitlen %d\n", bitlen);
 103                 return 1;
 104         }
 105
 106         slave = spi_setup_slave(bus, cs, 1000000, mode);
 107         if (!slave) {
 108                 printf("Invalid device %d:%d\n", bus, cs);
 109                 return 1;
 110         }
 111
 112         spi_claim_bus(slave);
 113         if(spi_xfer(slave, bitlen, dout, din,
 114                                 SPI_XFER_BEGIN | SPI_XFER_END) != 0) {
 115                 printf("Error during SPI transaction\n");
 116                 rcode = 1;
 117         } else {
 118                 for(j = 0; j < ((bitlen + 7) / 8); j++) {
 119                         printf("%02X", din[j]);
 120                 }
 121                 printf("\n");
 122         }
 123         spi_release_bus(slave);
 124         spi_free_slave(slave);
 125
 126         return rcode;
 127 }
 128
 129 /***************************************************/
 130
 131 U_BOOT_CMD(
 132         sspi,   5,      1,      do_spi,
 133         "SPI utility command",
 134         "[<bus>:]<cs>[.<mode>] <bit_len> <dout> - Send and receive bits\n"
 135         "<bus>     - Identifies the SPI bus\n"
 136         "<cs>      - Identifies the chip select\n"
 137         "<mode>    - Identifies the SPI mode to use\n"
 138         "<bit_len> - Number of bits to send (base 10)\n"
 139         "<dout>    - Hexadecimal string that gets sent"
 140 );