3 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
5 * SPDX-License-Identifier: GPL-2.0+
9 * SPI Read/Write Utilities
18 /*-----------------------------------------------------------------------
23 # define MAX_SPI_BYTES 32 /* Maximum number of bytes we can handle */
26 #ifndef CONFIG_DEFAULT_SPI_BUS
27 # define CONFIG_DEFAULT_SPI_BUS 0
29 #ifndef CONFIG_DEFAULT_SPI_MODE
30 # define CONFIG_DEFAULT_SPI_MODE SPI_MODE_0
34 * Values from last command.
36 static unsigned int bus;
37 static unsigned int cs;
38 static unsigned int mode;
40 static uchar dout[MAX_SPI_BYTES];
41 static uchar din[MAX_SPI_BYTES];
43 static int do_spi_xfer(int bus, int cs)
45 struct spi_slave *slave;
52 snprintf(name, sizeof(name), "generic_%d:%d", bus, cs);
56 ret = spi_get_bus_and_cs(bus, cs, 1000000, mode, "spi_generic_drv",
61 slave = spi_setup_slave(bus, cs, 1000000, mode);
63 printf("Invalid device %d:%d\n", bus, cs);
68 ret = spi_claim_bus(slave);
71 ret = spi_xfer(slave, bitlen, dout, din,
72 SPI_XFER_BEGIN | SPI_XFER_END);
74 /* We don't get an error code in this case */
79 printf("Error %d during SPI transaction\n", ret);
83 for (j = 0; j < ((bitlen + 7) / 8); j++)
84 printf("%02X", din[j]);
88 spi_release_bus(slave);
90 spi_free_slave(slave);
100 * spi {dev} {num_bits} {dout}
101 * {dev} is the device number for controlling chip select (see TBD)
102 * {num_bits} is the number of bits to send & receive (base 10)
103 * {dout} is a hexadecimal string of data to send
104 * The command prints out the hexadecimal string received via SPI.
107 int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
114 * We use the last specified parameters, unless new ones are
118 if ((flag & CMD_FLAG_REPEAT) == 0)
121 mode = CONFIG_DEFAULT_SPI_MODE;
122 bus = simple_strtoul(argv[1], &cp, 10);
124 cs = simple_strtoul(cp+1, &cp, 10);
127 bus = CONFIG_DEFAULT_SPI_BUS;
130 mode = simple_strtoul(cp+1, NULL, 10);
133 bitlen = simple_strtoul(argv[2], NULL, 10);
136 for(j = 0; *cp; j++, cp++) {
139 tmp -= ('A' - '0') - 10;
143 printf("Hex conversion error on %c\n", *cp);
147 dout[j / 2] = (tmp << 4);
154 if ((bitlen < 0) || (bitlen > (MAX_SPI_BYTES * 8))) {
155 printf("Invalid bitlen %d\n", bitlen);
159 if (do_spi_xfer(bus, cs))
165 /***************************************************/
169 "SPI utility command",
170 "[<bus>:]<cs>[.<mode>] <bit_len> <dout> - Send and receive bits\n"
171 "<bus> - Identifies the SPI bus\n"
172 "<cs> - Identifies the chip select\n"
173 "<mode> - Identifies the SPI mode to use\n"
174 "<bit_len> - Number of bits to send (base 10)\n"
175 "<dout> - Hexadecimal string that gets sent"