1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2009-2010 Pengutronix
* Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
*
* loosely based on an earlier driver that has
* Copyright 2009 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
*/
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/mfd/core.h>
#include <linux/mfd/mc13xxx.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/err.h>
#include <linux/spi/spi.h>
#include "mc13xxx.h"
static const struct spi_device_id mc13xxx_device_id[] = {
{
.name = "mc13783",
.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13783,
}, {
.name = "mc13892",
.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc13892,
}, {
.name = "mc34708",
.driver_data = (kernel_ulong_t)&mc13xxx_variant_mc34708,
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(spi, mc13xxx_device_id);
static const struct of_device_id mc13xxx_dt_ids[] = {
{ .compatible = "fsl,mc13783", .data = &mc13xxx_variant_mc13783, },
{ .compatible = "fsl,mc13892", .data = &mc13xxx_variant_mc13892, },
{ .compatible = "fsl,mc34708", .data = &mc13xxx_variant_mc34708, },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mc13xxx_dt_ids);
static const struct regmap_config mc13xxx_regmap_spi_config = {
.reg_bits = 7,
.pad_bits = 1,
.val_bits = 24,
.write_flag_mask = 0x80,
.max_register = MC13XXX_NUMREGS,
.cache_type = REGCACHE_NONE,
.use_single_read = true,
.use_single_write = true,
};
static int mc13xxx_spi_read(void *context, const void *reg, size_t reg_size,
void *val, size_t val_size)
{
unsigned char w[4] = { *((unsigned char *) reg), 0, 0, 0};
unsigned char r[4];
unsigned char *p = val;
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
struct spi_transfer t = {
.tx_buf = w,
.rx_buf = r,
.len = 4,
};
struct spi_message m;
int ret;
if (val_size != 3 || reg_size != 1)
return -ENOTSUPP;
spi_message_init(&m);
spi_message_add_tail(&t, &m);
ret = spi_sync(spi, &m);
memcpy(p, &r[1], 3);
return ret;
}
static int mc13xxx_spi_write(void *context, const void *data, size_t count)
{
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
const char *reg = data;
if (count != 4)
return -ENOTSUPP;
/* include errata fix for spi audio problems */
if (*reg == MC13783_AUDIO_CODEC || *reg == MC13783_AUDIO_DAC)
spi_write(spi, data, count);
return spi_write(spi, data, count);
}
/*
* We cannot use regmap-spi generic bus implementation here.
* The MC13783 chip will get corrupted if CS signal is deasserted
* and on i.Mx31 SoC (the target SoC for MC13783 PMIC) the SPI controller
* has the following errata (DSPhl22960):
* "The CSPI negates SS when the FIFO becomes empty with
* SSCTL= 0. Software cannot guarantee that the FIFO will not
* drain because of higher priority interrupts and the
* non-realtime characteristics of the operating system. As a
* result, the SS will negate before all of the data has been
* transferred to/from the peripheral."
* We workaround this by accessing the SPI controller with a
* single transfer.
*/
static struct regmap_bus regmap_mc13xxx_bus = {
.write = mc13xxx_spi_write,
.read = mc13xxx_spi_read,
};
static int mc13xxx_spi_probe(struct spi_device *spi)
{
struct mc13xxx *mc13xxx;
int ret;
mc13xxx = devm_kzalloc(&spi->dev, sizeof(*mc13xxx), GFP_KERNEL);
if (!mc13xxx)
return -ENOMEM;
dev_set_drvdata(&spi->dev, mc13xxx);
spi->mode = SPI_MODE_0 | SPI_CS_HIGH;
mc13xxx->irq = spi->irq;
spi->max_speed_hz = spi->max_speed_hz ? : 26000000;
ret = spi_setup(spi);
if (ret)
return ret;
mc13xxx->regmap = devm_regmap_init(&spi->dev, ®map_mc13xxx_bus,
&spi->dev,
&mc13xxx_regmap_spi_config);
if (IS_ERR(mc13xxx->regmap)) {
ret = PTR_ERR(mc13xxx->regmap);
dev_err(&spi->dev, "Failed to initialize regmap: %d\n", ret);
return ret;
}
if (spi->dev.of_node) {
const struct of_device_id *of_id =
of_match_device(mc13xxx_dt_ids, &spi->dev);
mc13xxx->variant = of_id->data;
} else {
const struct spi_device_id *id_entry = spi_get_device_id(spi);
mc13xxx->variant = (void *)id_entry->driver_data;
}
return mc13xxx_common_init(&spi->dev);
}
static void mc13xxx_spi_remove(struct spi_device *spi)
{
mc13xxx_common_exit(&spi->dev);
}
static struct spi_driver mc13xxx_spi_driver = {
.id_table = mc13xxx_device_id,
.driver = {
.name = "mc13xxx",
.of_match_table = mc13xxx_dt_ids,
},
.probe = mc13xxx_spi_probe,
.remove = mc13xxx_spi_remove,
};
static int __init mc13xxx_init(void)
{
return spi_register_driver(&mc13xxx_spi_driver);
}
subsys_initcall(mc13xxx_init);
static void __exit mc13xxx_exit(void)
{
spi_unregister_driver(&mc13xxx_spi_driver);
}
module_exit(mc13xxx_exit);
MODULE_DESCRIPTION("Core driver for Freescale MC13XXX PMIC");
MODULE_AUTHOR("Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>");
MODULE_LICENSE("GPL v2");
|
