xref: /linux/drivers/base/regmap/regmap-spi.c (revision 0d3b051adbb72ed81956447d0d1e54d5943ee6f5)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Register map access API - SPI support
4 //
5 // Copyright 2011 Wolfson Microelectronics plc
6 //
7 // Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
8 
9 #include <linux/regmap.h>
10 #include <linux/spi/spi.h>
11 #include <linux/module.h>
12 
13 #include "internal.h"
14 
15 struct regmap_async_spi {
16 	struct regmap_async core;
17 	struct spi_message m;
18 	struct spi_transfer t[2];
19 };
20 
21 static void regmap_spi_complete(void *data)
22 {
23 	struct regmap_async_spi *async = data;
24 
25 	regmap_async_complete_cb(&async->core, async->m.status);
26 }
27 
28 static int regmap_spi_write(void *context, const void *data, size_t count)
29 {
30 	struct device *dev = context;
31 	struct spi_device *spi = to_spi_device(dev);
32 
33 	return spi_write(spi, data, count);
34 }
35 
36 static int regmap_spi_gather_write(void *context,
37 				   const void *reg, size_t reg_len,
38 				   const void *val, size_t val_len)
39 {
40 	struct device *dev = context;
41 	struct spi_device *spi = to_spi_device(dev);
42 	struct spi_message m;
43 	struct spi_transfer t[2] = { { .tx_buf = reg, .len = reg_len, },
44 				     { .tx_buf = val, .len = val_len, }, };
45 
46 	spi_message_init(&m);
47 	spi_message_add_tail(&t[0], &m);
48 	spi_message_add_tail(&t[1], &m);
49 
50 	return spi_sync(spi, &m);
51 }
52 
53 static int regmap_spi_async_write(void *context,
54 				  const void *reg, size_t reg_len,
55 				  const void *val, size_t val_len,
56 				  struct regmap_async *a)
57 {
58 	struct regmap_async_spi *async = container_of(a,
59 						      struct regmap_async_spi,
60 						      core);
61 	struct device *dev = context;
62 	struct spi_device *spi = to_spi_device(dev);
63 
64 	async->t[0].tx_buf = reg;
65 	async->t[0].len = reg_len;
66 	async->t[1].tx_buf = val;
67 	async->t[1].len = val_len;
68 
69 	spi_message_init(&async->m);
70 	spi_message_add_tail(&async->t[0], &async->m);
71 	if (val)
72 		spi_message_add_tail(&async->t[1], &async->m);
73 
74 	async->m.complete = regmap_spi_complete;
75 	async->m.context = async;
76 
77 	return spi_async(spi, &async->m);
78 }
79 
80 static struct regmap_async *regmap_spi_async_alloc(void)
81 {
82 	struct regmap_async_spi *async_spi;
83 
84 	async_spi = kzalloc(sizeof(*async_spi), GFP_KERNEL);
85 	if (!async_spi)
86 		return NULL;
87 
88 	return &async_spi->core;
89 }
90 
91 static int regmap_spi_read(void *context,
92 			   const void *reg, size_t reg_size,
93 			   void *val, size_t val_size)
94 {
95 	struct device *dev = context;
96 	struct spi_device *spi = to_spi_device(dev);
97 
98 	return spi_write_then_read(spi, reg, reg_size, val, val_size);
99 }
100 
101 static const struct regmap_bus regmap_spi = {
102 	.write = regmap_spi_write,
103 	.gather_write = regmap_spi_gather_write,
104 	.async_write = regmap_spi_async_write,
105 	.async_alloc = regmap_spi_async_alloc,
106 	.read = regmap_spi_read,
107 	.read_flag_mask = 0x80,
108 	.reg_format_endian_default = REGMAP_ENDIAN_BIG,
109 	.val_format_endian_default = REGMAP_ENDIAN_BIG,
110 };
111 
112 struct regmap *__regmap_init_spi(struct spi_device *spi,
113 				 const struct regmap_config *config,
114 				 struct lock_class_key *lock_key,
115 				 const char *lock_name)
116 {
117 	return __regmap_init(&spi->dev, &regmap_spi, &spi->dev, config,
118 			     lock_key, lock_name);
119 }
120 EXPORT_SYMBOL_GPL(__regmap_init_spi);
121 
122 struct regmap *__devm_regmap_init_spi(struct spi_device *spi,
123 				      const struct regmap_config *config,
124 				      struct lock_class_key *lock_key,
125 				      const char *lock_name)
126 {
127 	return __devm_regmap_init(&spi->dev, &regmap_spi, &spi->dev, config,
128 				  lock_key, lock_name);
129 }
130 EXPORT_SYMBOL_GPL(__devm_regmap_init_spi);
131 
132 MODULE_LICENSE("GPL");
133