cmd/spi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * (C) Copyright 2002
   4  * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
   5  */
   6
   7 /*
   8  * SPI Read/Write Utilities
   9  */
  10
  11 #include <common.h>
  12 #include <command.h>
  13 #include <dm.h>
  14 #include <errno.h>
  15 #include <spi.h>
  16
  17 /*-----------------------------------------------------------------------
  18  * Definitions
  19  */
  20
  21 #ifndef MAX_SPI_BYTES
  22 #   define MAX_SPI_BYTES 32     /* Maximum number of bytes we can handle */
  23 #endif
  24
  25 /*
  26  * Values from last command.
  27  */
  28 static unsigned int     bus;
  29 static unsigned int     cs;
  30 static unsigned int     mode;
  31 static unsigned int     freq;
  32 static int              bitlen;
  33 static uchar            dout[MAX_SPI_BYTES];
  34 static uchar            din[MAX_SPI_BYTES];
  35
  36 static int do_spi_xfer(int bus, int cs)
  37 {
  38         struct spi_slave *slave;
  39         int ret = 0;
  40
  41 #if CONFIG_IS_ENABLED(DM_SPI)
  42         char name[30], *str;
  43         struct udevice *dev;
  44
  45         snprintf(name, sizeof(name), "generic_%d:%d", bus, cs);
  46         str = strdup(name);
  47         if (!str)
  48                 return -ENOMEM;
  49         ret = spi_get_bus_and_cs(bus, cs, freq, mode, "spi_generic_drv",
  50                                  str, &dev, &slave);
  51         if (ret)
  52                 return ret;
  53 #else
  54         slave = spi_setup_slave(bus, cs, freq, mode);
  55         if (!slave) {
  56                 printf("Invalid device %d:%d\n", bus, cs);
  57                 return -EINVAL;
  58         }
  59 #endif
  60
  61         ret = spi_claim_bus(slave);
  62         if (ret)
  63                 goto done;
  64         ret = spi_xfer(slave, bitlen, dout, din,
  65                        SPI_XFER_BEGIN | SPI_XFER_END);
  66 #if !CONFIG_IS_ENABLED(DM_SPI)
  67         /* We don't get an error code in this case */
  68         if (ret)
  69                 ret = -EIO;
  70 #endif
  71         if (ret) {
  72                 printf("Error %d during SPI transaction\n", ret);
  73         } else {
  74                 int j;
  75
  76                 for (j = 0; j < ((bitlen + 7) / 8); j++)
  77                         printf("%02X", din[j]);
  78                 printf("\n");
  79         }
  80 done:
  81         spi_release_bus(slave);
  82 #if !CONFIG_IS_ENABLED(DM_SPI)
  83         spi_free_slave(slave);
  84 #endif
  85
  86         return ret;
  87 }
  88
  89 /*
  90  * SPI read/write
  91  *
  92  * Syntax:
  93  *   spi {dev} {num_bits} {dout}
  94  *     {dev} is the device number for controlling chip select (see TBD)
  95  *     {num_bits} is the number of bits to send & receive (base 10)
  96  *     {dout} is a hexadecimal string of data to send
  97  * The command prints out the hexadecimal string received via SPI.
  98  */
  99
 100 int do_spi(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 101 {
 102         char  *cp = 0;
 103         uchar tmp;
 104         int   j;
 105
 106         /*
 107          * We use the last specified parameters, unless new ones are
 108          * entered.
 109          */
 110         if (freq == 0)
 111                 freq = 1000000;
 112
 113         if ((flag & CMD_FLAG_REPEAT) == 0)
 114         {
 115                 if (argc >= 2) {
 116                         mode = CONFIG_DEFAULT_SPI_MODE;
 117                         bus = dectoul(argv[1], &cp);
 118                         if (*cp == ':') {
 119                                 cs = dectoul(cp + 1, &cp);
 120                         } else {
 121                                 cs = bus;
 122                                 bus = CONFIG_DEFAULT_SPI_BUS;
 123                         }
 124                         if (*cp == '.')
 125                                 mode = dectoul(cp + 1, &cp);
 126                         if (*cp == '@')
 127                                 freq = dectoul(cp + 1, &cp);
 128                 }
 129                 if (argc >= 3)
 130                         bitlen = dectoul(argv[2], NULL);
 131                 if (argc >= 4) {
 132                         cp = argv[3];
 133                         for(j = 0; *cp; j++, cp++) {
 134                                 tmp = *cp - '0';
 135                                 if(tmp > 9)
 136                                         tmp -= ('A' - '0') - 10;
 137                                 if(tmp > 15)
 138                                         tmp -= ('a' - 'A');
 139                                 if(tmp > 15) {
 140                                         printf("Hex conversion error on %c\n", *cp);
 141                                         return 1;
 142                                 }
 143                                 if((j % 2) == 0)
 144                                         dout[j / 2] = (tmp << 4);
 145                                 else
 146                                         dout[j / 2] |= tmp;
 147                         }
 148                 }
 149         }
 150
 151         if ((bitlen < 0) || (bitlen >  (MAX_SPI_BYTES * 8))) {
 152                 printf("Invalid bitlen %d\n", bitlen);
 153                 return 1;
 154         }
 155
 156         if (do_spi_xfer(bus, cs))
 157                 return 1;
 158
 159         return 0;
 160 }
 161
 162 /***************************************************/
 163
 164 U_BOOT_CMD(
 165         sspi,   5,      1,      do_spi,
 166         "SPI utility command",
 167         "[<bus>:]<cs>[.<mode>][@<freq>] <bit_len> <dout> - Send and receive bits\n"
 168         "<bus>     - Identifies the SPI bus\n"
 169         "<cs>      - Identifies the chip select\n"
 170         "<mode>    - Identifies the SPI mode to use\n"
 171         "<freq>    - Identifies the SPI bus frequency in Hz\n"
 172         "<bit_len> - Number of bits to send (base 10)\n"
 173         "<dout>    - Hexadecimal string that gets sent"
 174 );