xref: /openbmc/u-boot/cmd/spi.c (revision ff6552e8)
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 <dm.h>
15 #include <errno.h>
16 #include <spi.h>
17 
18 /*-----------------------------------------------------------------------
19  * Definitions
20  */
21 
22 #ifndef MAX_SPI_BYTES
23 #   define MAX_SPI_BYTES 32	/* Maximum number of bytes we can handle */
24 #endif
25 
26 #ifndef CONFIG_DEFAULT_SPI_BUS
27 #   define CONFIG_DEFAULT_SPI_BUS	0
28 #endif
29 #ifndef CONFIG_DEFAULT_SPI_MODE
30 #   define CONFIG_DEFAULT_SPI_MODE	SPI_MODE_0
31 #endif
32 
33 /*
34  * Values from last command.
35  */
36 static unsigned int	bus;
37 static unsigned int	cs;
38 static unsigned int	mode;
39 static int   		bitlen;
40 static uchar 		dout[MAX_SPI_BYTES];
41 static uchar 		din[MAX_SPI_BYTES];
42 
43 static int do_spi_xfer(int bus, int cs)
44 {
45 	struct spi_slave *slave;
46 	int ret = 0;
47 
48 #ifdef CONFIG_DM_SPI
49 	char name[30], *str;
50 	struct udevice *dev;
51 
52 	snprintf(name, sizeof(name), "generic_%d:%d", bus, cs);
53 	str = strdup(name);
54 	if (!str)
55 		return -ENOMEM;
56 	ret = spi_get_bus_and_cs(bus, cs, 1000000, mode, "spi_generic_drv",
57 				 str, &dev, &slave);
58 	if (ret)
59 		return ret;
60 #else
61 	slave = spi_setup_slave(bus, cs, 1000000, mode);
62 	if (!slave) {
63 		printf("Invalid device %d:%d\n", bus, cs);
64 		return -EINVAL;
65 	}
66 #endif
67 
68 	ret = spi_claim_bus(slave);
69 	if (ret)
70 		goto done;
71 	ret = spi_xfer(slave, bitlen, dout, din,
72 		       SPI_XFER_BEGIN | SPI_XFER_END);
73 #ifndef CONFIG_DM_SPI
74 	/* We don't get an error code in this case */
75 	if (ret)
76 		ret = -EIO;
77 #endif
78 	if (ret) {
79 		printf("Error %d during SPI transaction\n", ret);
80 	} else {
81 		int j;
82 
83 		for (j = 0; j < ((bitlen + 7) / 8); j++)
84 			printf("%02X", din[j]);
85 		printf("\n");
86 	}
87 done:
88 	spi_release_bus(slave);
89 #ifndef CONFIG_DM_SPI
90 	spi_free_slave(slave);
91 #endif
92 
93 	return ret;
94 }
95 
96 /*
97  * SPI read/write
98  *
99  * Syntax:
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.
105  */
106 
107 int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
108 {
109 	char  *cp = 0;
110 	uchar tmp;
111 	int   j;
112 
113 	/*
114 	 * We use the last specified parameters, unless new ones are
115 	 * entered.
116 	 */
117 
118 	if ((flag & CMD_FLAG_REPEAT) == 0)
119 	{
120 		if (argc >= 2) {
121 			mode = CONFIG_DEFAULT_SPI_MODE;
122 			bus = simple_strtoul(argv[1], &cp, 10);
123 			if (*cp == ':') {
124 				cs = simple_strtoul(cp+1, &cp, 10);
125 			} else {
126 				cs = bus;
127 				bus = CONFIG_DEFAULT_SPI_BUS;
128 			}
129 			if (*cp == '.')
130 				mode = simple_strtoul(cp+1, NULL, 10);
131 		}
132 		if (argc >= 3)
133 			bitlen = simple_strtoul(argv[2], NULL, 10);
134 		if (argc >= 4) {
135 			cp = argv[3];
136 			for(j = 0; *cp; j++, cp++) {
137 				tmp = *cp - '0';
138 				if(tmp > 9)
139 					tmp -= ('A' - '0') - 10;
140 				if(tmp > 15)
141 					tmp -= ('a' - 'A');
142 				if(tmp > 15) {
143 					printf("Hex conversion error on %c\n", *cp);
144 					return 1;
145 				}
146 				if((j % 2) == 0)
147 					dout[j / 2] = (tmp << 4);
148 				else
149 					dout[j / 2] |= tmp;
150 			}
151 		}
152 	}
153 
154 	if ((bitlen < 0) || (bitlen >  (MAX_SPI_BYTES * 8))) {
155 		printf("Invalid bitlen %d\n", bitlen);
156 		return 1;
157 	}
158 
159 	if (do_spi_xfer(bus, cs))
160 		return 1;
161 
162 	return 0;
163 }
164 
165 /***************************************************/
166 
167 U_BOOT_CMD(
168 	sspi,	5,	1,	do_spi,
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"
176 );
177