xref: /openbmc/u-boot/cmd/spi.c (revision ee943655)
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 #ifndef CONFIG_DEFAULT_SPI_BUS
26 #   define CONFIG_DEFAULT_SPI_BUS	0
27 #endif
28 #ifndef CONFIG_DEFAULT_SPI_MODE
29 #   define CONFIG_DEFAULT_SPI_MODE	SPI_MODE_0
30 #endif
31 
32 /*
33  * Values from last command.
34  */
35 static unsigned int	bus;
36 static unsigned int	cs;
37 static unsigned int	mode;
38 static int   		bitlen;
39 static uchar 		dout[MAX_SPI_BYTES];
40 static uchar 		din[MAX_SPI_BYTES];
41 
42 static int do_spi_xfer(int bus, int cs)
43 {
44 	struct spi_slave *slave;
45 	int ret = 0;
46 
47 #ifdef CONFIG_DM_SPI
48 	char name[30], *str;
49 	struct udevice *dev;
50 
51 	snprintf(name, sizeof(name), "generic_%d:%d", bus, cs);
52 	str = strdup(name);
53 	if (!str)
54 		return -ENOMEM;
55 	ret = spi_get_bus_and_cs(bus, cs, 1000000, mode, "spi_generic_drv",
56 				 str, &dev, &slave);
57 	if (ret)
58 		return ret;
59 #else
60 	slave = spi_setup_slave(bus, cs, 1000000, mode);
61 	if (!slave) {
62 		printf("Invalid device %d:%d\n", bus, cs);
63 		return -EINVAL;
64 	}
65 #endif
66 
67 	ret = spi_claim_bus(slave);
68 	if (ret)
69 		goto done;
70 	ret = spi_xfer(slave, bitlen, dout, din,
71 		       SPI_XFER_BEGIN | SPI_XFER_END);
72 #ifndef CONFIG_DM_SPI
73 	/* We don't get an error code in this case */
74 	if (ret)
75 		ret = -EIO;
76 #endif
77 	if (ret) {
78 		printf("Error %d during SPI transaction\n", ret);
79 	} else {
80 		int j;
81 
82 		for (j = 0; j < ((bitlen + 7) / 8); j++)
83 			printf("%02X", din[j]);
84 		printf("\n");
85 	}
86 done:
87 	spi_release_bus(slave);
88 #ifndef CONFIG_DM_SPI
89 	spi_free_slave(slave);
90 #endif
91 
92 	return ret;
93 }
94 
95 /*
96  * SPI read/write
97  *
98  * Syntax:
99  *   spi {dev} {num_bits} {dout}
100  *     {dev} is the device number for controlling chip select (see TBD)
101  *     {num_bits} is the number of bits to send & receive (base 10)
102  *     {dout} is a hexadecimal string of data to send
103  * The command prints out the hexadecimal string received via SPI.
104  */
105 
106 int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
107 {
108 	char  *cp = 0;
109 	uchar tmp;
110 	int   j;
111 
112 	/*
113 	 * We use the last specified parameters, unless new ones are
114 	 * entered.
115 	 */
116 
117 	if ((flag & CMD_FLAG_REPEAT) == 0)
118 	{
119 		if (argc >= 2) {
120 			mode = CONFIG_DEFAULT_SPI_MODE;
121 			bus = simple_strtoul(argv[1], &cp, 10);
122 			if (*cp == ':') {
123 				cs = simple_strtoul(cp+1, &cp, 10);
124 			} else {
125 				cs = bus;
126 				bus = CONFIG_DEFAULT_SPI_BUS;
127 			}
128 			if (*cp == '.')
129 				mode = simple_strtoul(cp+1, NULL, 10);
130 		}
131 		if (argc >= 3)
132 			bitlen = simple_strtoul(argv[2], NULL, 10);
133 		if (argc >= 4) {
134 			cp = argv[3];
135 			for(j = 0; *cp; j++, cp++) {
136 				tmp = *cp - '0';
137 				if(tmp > 9)
138 					tmp -= ('A' - '0') - 10;
139 				if(tmp > 15)
140 					tmp -= ('a' - 'A');
141 				if(tmp > 15) {
142 					printf("Hex conversion error on %c\n", *cp);
143 					return 1;
144 				}
145 				if((j % 2) == 0)
146 					dout[j / 2] = (tmp << 4);
147 				else
148 					dout[j / 2] |= tmp;
149 			}
150 		}
151 	}
152 
153 	if ((bitlen < 0) || (bitlen >  (MAX_SPI_BYTES * 8))) {
154 		printf("Invalid bitlen %d\n", bitlen);
155 		return 1;
156 	}
157 
158 	if (do_spi_xfer(bus, cs))
159 		return 1;
160 
161 	return 0;
162 }
163 
164 /***************************************************/
165 
166 U_BOOT_CMD(
167 	sspi,	5,	1,	do_spi,
168 	"SPI utility command",
169 	"[<bus>:]<cs>[.<mode>] <bit_len> <dout> - Send and receive bits\n"
170 	"<bus>     - Identifies the SPI bus\n"
171 	"<cs>      - Identifies the chip select\n"
172 	"<mode>    - Identifies the SPI mode to use\n"
173 	"<bit_len> - Number of bits to send (base 10)\n"
174 	"<dout>    - Hexadecimal string that gets sent"
175 );
176