1 /*
2 * Simulate a SPI port
3 *
4 * Copyright (c) 2011-2013 The Chromium OS Authors.
5 * See file CREDITS for list of people who contributed to this
6 * project.
7 *
8 * Licensed under the GPL-2 or later.
9 */
10
11 #define LOG_CATEGORY UCLASS_SPI
12
13 #include <common.h>
14 #include <dm.h>
15 #include <malloc.h>
16 #include <spi.h>
17 #include <spi_flash.h>
18 #include <os.h>
19
20 #include <linux/errno.h>
21 #include <asm/spi.h>
22 #include <asm/state.h>
23 #include <dm/device-internal.h>
24
25 #ifndef CONFIG_SPI_IDLE_VAL
26 # define CONFIG_SPI_IDLE_VAL 0xFF
27 #endif
28
sandbox_spi_parse_spec(const char * arg,unsigned long * bus,unsigned long * cs)29 const char *sandbox_spi_parse_spec(const char *arg, unsigned long *bus,
30 unsigned long *cs)
31 {
32 char *endp;
33
34 *bus = simple_strtoul(arg, &endp, 0);
35 if (*endp != ':' || *bus >= CONFIG_SANDBOX_SPI_MAX_BUS)
36 return NULL;
37
38 *cs = simple_strtoul(endp + 1, &endp, 0);
39 if (*endp != ':' || *cs >= CONFIG_SANDBOX_SPI_MAX_CS)
40 return NULL;
41
42 return endp + 1;
43 }
44
sandbox_spi_get_emul(struct sandbox_state * state,struct udevice * bus,struct udevice * slave,struct udevice ** emulp)45 __weak int sandbox_spi_get_emul(struct sandbox_state *state,
46 struct udevice *bus, struct udevice *slave,
47 struct udevice **emulp)
48 {
49 return -ENOENT;
50 }
51
sandbox_spi_xfer(struct udevice * slave,unsigned int bitlen,const void * dout,void * din,unsigned long flags)52 static int sandbox_spi_xfer(struct udevice *slave, unsigned int bitlen,
53 const void *dout, void *din, unsigned long flags)
54 {
55 struct udevice *bus = slave->parent;
56 struct sandbox_state *state = state_get_current();
57 struct dm_spi_emul_ops *ops;
58 struct udevice *emul;
59 uint bytes = bitlen / 8, i;
60 int ret;
61 uint busnum, cs;
62
63 if (bitlen == 0)
64 return 0;
65
66 /* we can only do 8 bit transfers */
67 if (bitlen % 8) {
68 printf("sandbox_spi: xfer: invalid bitlen size %u; needs to be 8bit\n",
69 bitlen);
70 return -EINVAL;
71 }
72
73 busnum = bus->seq;
74 cs = spi_chip_select(slave);
75 if (busnum >= CONFIG_SANDBOX_SPI_MAX_BUS ||
76 cs >= CONFIG_SANDBOX_SPI_MAX_CS) {
77 printf("%s: busnum=%u, cs=%u: out of range\n", __func__,
78 busnum, cs);
79 return -ENOENT;
80 }
81 ret = sandbox_spi_get_emul(state, bus, slave, &emul);
82 if (ret) {
83 printf("%s: busnum=%u, cs=%u: no emulation available (err=%d)\n",
84 __func__, busnum, cs, ret);
85 return -ENOENT;
86 }
87 ret = device_probe(emul);
88 if (ret)
89 return ret;
90
91 ops = spi_emul_get_ops(emul);
92 ret = ops->xfer(emul, bitlen, dout, din, flags);
93
94 log_content("sandbox_spi: xfer: got back %i (that's %s)\n rx:",
95 ret, ret ? "bad" : "good");
96 if (din) {
97 for (i = 0; i < bytes; ++i)
98 log_content(" %u:%02x", i, ((u8 *)din)[i]);
99 }
100 log_content("\n");
101
102 return ret;
103 }
104
sandbox_spi_set_speed(struct udevice * bus,uint speed)105 static int sandbox_spi_set_speed(struct udevice *bus, uint speed)
106 {
107 return 0;
108 }
109
sandbox_spi_set_mode(struct udevice * bus,uint mode)110 static int sandbox_spi_set_mode(struct udevice *bus, uint mode)
111 {
112 return 0;
113 }
114
sandbox_cs_info(struct udevice * bus,uint cs,struct spi_cs_info * info)115 static int sandbox_cs_info(struct udevice *bus, uint cs,
116 struct spi_cs_info *info)
117 {
118 /* Always allow activity on CS 0 */
119 if (cs >= 1)
120 return -ENODEV;
121
122 return 0;
123 }
124
125 static const struct dm_spi_ops sandbox_spi_ops = {
126 .xfer = sandbox_spi_xfer,
127 .set_speed = sandbox_spi_set_speed,
128 .set_mode = sandbox_spi_set_mode,
129 .cs_info = sandbox_cs_info,
130 };
131
132 static const struct udevice_id sandbox_spi_ids[] = {
133 { .compatible = "sandbox,spi" },
134 { }
135 };
136
137 U_BOOT_DRIVER(spi_sandbox) = {
138 .name = "spi_sandbox",
139 .id = UCLASS_SPI,
140 .of_match = sandbox_spi_ids,
141 .ops = &sandbox_spi_ops,
142 };
143