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gerrit.devboardsforandroid.linaro.org / platform / external / u-boot / d33776e43dc8471ab03920dda77b00333a8ddd3e / . / drivers / spmi / spmi-sandbox.c
blob: 2f0fea07e8012f30171ac9d22a7b243702a8672b [file] [log] [blame]
Mateusz Kulikowskid33776e2016-03-31 23:12:28 +0200[diff] [blame^]1/*
2 * Sample SPMI bus driver
3 *
4 * It emulates bus with single pm8916-like pmic that has only GPIO reigsters.
5 *
6 * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
7 *
8 * SPDX-License-Identifier: GPL-2.0+
9 */
10
11#include <common.h>
12#include <dm.h>
13#include <errno.h>
14#include <spmi/spmi.h>
15#include <asm/gpio.h>
16#include <asm/io.h>
17
18DECLARE_GLOBAL_DATA_PTR;
19
20#define EMUL_GPIO_PID_START 0xC0
21#define EMUL_GPIO_PID_END 0xC3
22
23#define EMUL_GPIO_COUNT 4
24
25#define EMUL_GPIO_REG_END 0x46 /* Last valid register */
26
27#define EMUL_PERM_R 0x1
28#define EMUL_PERM_W 0x2
29#define EMUL_PERM_RW (EMUL_PERM_R | EMUL_PERM_W)
30
31struct sandbox_emul_fake_regs {
32 u8 value;
33 u8 access_mask;
34 u8 perms; /* Access permissions */
35};
36
37struct sandbox_emul_gpio {
38 struct sandbox_emul_fake_regs r[EMUL_GPIO_REG_END]; /* Fake registers */
39};
40
41struct sandbox_spmi_priv {
42 struct sandbox_emul_gpio gpios[EMUL_GPIO_COUNT];
43};
44
45/* Check if valid register was requested */
46static bool check_address_valid(int usid, int pid, int off)
47{
48 if (usid != 0)
49 return false;
50 if (pid < EMUL_GPIO_PID_START || pid > EMUL_GPIO_PID_END)
51 return false;
52 if (off > EMUL_GPIO_REG_END)
53 return false;
54 return true;
55}
56
57static int sandbox_spmi_write(struct udevice *dev, int usid, int pid, int off,
58 uint8_t val)
59{
60 struct sandbox_spmi_priv *priv = dev_get_priv(dev);
61 struct sandbox_emul_fake_regs *regs;
62
63 if (!check_address_valid(usid, pid, off))
64 return -EIO;
65
66 regs = priv->gpios[pid & 0x3].r; /* Last 3 bits of pid are gpio # */
67
68 switch (off) {
69 case 0x40: /* Control */
70 val &= regs[off].access_mask;
71 if (((val & 0x30) == 0x10) || ((val & 0x30) == 0x20)) {
72 /* out/inout - set status register */
73 regs[0x8].value &= ~0x1;
74 regs[0x8].value |= val & 0x1;
75 }
76 break;
77 default:
78 if (regs[off].perms & EMUL_PERM_W)
79 regs[off].value = val & regs[off].access_mask;
80 }
81 return 0;
82}
83
84static int sandbox_spmi_read(struct udevice *dev, int usid, int pid, int off)
85{
86 struct sandbox_spmi_priv *priv = dev_get_priv(dev);
87 struct sandbox_emul_fake_regs *regs;
88
89 if (!check_address_valid(usid, pid, off))
90 return -EIO;
91
92 regs = priv->gpios[pid & 0x3].r; /* Last 3 bits of pid are gpio # */
93
94 if (regs[0x46].value == 0) /* Block disabled */
95 return 0;
96
97 switch (off) {
98 case 0x8: /* Status */
99 if (regs[0x46].value == 0) /* Block disabled */
100 return 0;
101 return regs[off].value;
102 default:
103 if (regs[off].perms & EMUL_PERM_R)
104 return regs[off].value;
105 else
106 return 0;
107 }
108}
109
110static struct dm_spmi_ops sandbox_spmi_ops = {
111 .read = sandbox_spmi_read,
112 .write = sandbox_spmi_write,
113};
114
115static int sandbox_spmi_probe(struct udevice *dev)
116{
117 struct sandbox_spmi_priv *priv = dev_get_priv(dev);
118 int i;
119
120 for (i = 0; i < EMUL_GPIO_COUNT; ++i) {
121 struct sandbox_emul_fake_regs *regs = priv->gpios[i].r;
122 regs[4].perms = EMUL_PERM_R;
123 regs[4].value = 0x10;
124 regs[5].perms = EMUL_PERM_R;
125 regs[5].value = 0x5;
126 regs[8].access_mask = 0x81;
127 regs[8].perms = EMUL_PERM_RW;
128 regs[0x40].access_mask = 0x7F;
129 regs[0x40].perms = EMUL_PERM_RW;
130 regs[0x41].access_mask = 7;
131 regs[0x41].perms = EMUL_PERM_RW;
132 regs[0x42].access_mask = 7;
133 regs[0x42].perms = EMUL_PERM_RW;
134 regs[0x42].value = 0x4;
135 regs[0x45].access_mask = 0x3F;
136 regs[0x45].perms = EMUL_PERM_RW;
137 regs[0x45].value = 0x1;
138 regs[0x46].access_mask = 0x80;
139 regs[0x46].perms = EMUL_PERM_RW;
140 regs[0x46].value = 0x80;
141 }
142 return 0;
143}
144
145static const struct udevice_id sandbox_spmi_ids[] = {
146 { .compatible = "sandbox,spmi" },
147 { }
148};
149
150U_BOOT_DRIVER(msm_spmi) = {
151 .name = "sandbox_spmi",
152 .id = UCLASS_SPMI,
153 .of_match = sandbox_spmi_ids,
154 .ops = &sandbox_spmi_ops,
155 .probe = sandbox_spmi_probe,
156 .priv_auto_alloc_size = sizeof(struct sandbox_spmi_priv),
157};