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