GNU Linux-libre 4.9.282-gnu1
[releases.git] / drivers / iio / pressure / bmp280-spi.c
1 /*
2  * SPI interface for the BMP280 driver
3  *
4  * Inspired by the older BMP085 driver drivers/misc/bmp085-spi.c
5  */
6 #include <linux/module.h>
7 #include <linux/spi/spi.h>
8 #include <linux/err.h>
9 #include <linux/regmap.h>
10
11 #include "bmp280.h"
12
13 static int bmp280_regmap_spi_write(void *context, const void *data,
14                                    size_t count)
15 {
16         struct device *dev = context;
17         struct spi_device *spi = to_spi_device(dev);
18         u8 buf[2];
19
20         memcpy(buf, data, 2);
21         /*
22          * The SPI register address (= full register address without bit 7) and
23          * the write command (bit7 = RW = '0')
24          */
25         buf[0] &= ~0x80;
26
27         return spi_write_then_read(spi, buf, 2, NULL, 0);
28 }
29
30 static int bmp280_regmap_spi_read(void *context, const void *reg,
31                                   size_t reg_size, void *val, size_t val_size)
32 {
33         struct device *dev = context;
34         struct spi_device *spi = to_spi_device(dev);
35
36         return spi_write_then_read(spi, reg, reg_size, val, val_size);
37 }
38
39 static struct regmap_bus bmp280_regmap_bus = {
40         .write = bmp280_regmap_spi_write,
41         .read = bmp280_regmap_spi_read,
42         .reg_format_endian_default = REGMAP_ENDIAN_BIG,
43         .val_format_endian_default = REGMAP_ENDIAN_BIG,
44 };
45
46 static int bmp280_spi_probe(struct spi_device *spi)
47 {
48         const struct spi_device_id *id = spi_get_device_id(spi);
49         struct regmap *regmap;
50         const struct regmap_config *regmap_config;
51         int ret;
52
53         spi->bits_per_word = 8;
54         ret = spi_setup(spi);
55         if (ret < 0) {
56                 dev_err(&spi->dev, "spi_setup failed!\n");
57                 return ret;
58         }
59
60         switch (id->driver_data) {
61         case BMP180_CHIP_ID:
62                 regmap_config = &bmp180_regmap_config;
63                 break;
64         case BMP280_CHIP_ID:
65         case BME280_CHIP_ID:
66                 regmap_config = &bmp280_regmap_config;
67                 break;
68         default:
69                 return -EINVAL;
70         }
71
72         regmap = devm_regmap_init(&spi->dev,
73                                   &bmp280_regmap_bus,
74                                   &spi->dev,
75                                   regmap_config);
76         if (IS_ERR(regmap)) {
77                 dev_err(&spi->dev, "failed to allocate register map\n");
78                 return PTR_ERR(regmap);
79         }
80
81         return bmp280_common_probe(&spi->dev,
82                                    regmap,
83                                    id->driver_data,
84                                    id->name,
85                                    spi->irq);
86 }
87
88 static int bmp280_spi_remove(struct spi_device *spi)
89 {
90         return bmp280_common_remove(&spi->dev);
91 }
92
93 static const struct of_device_id bmp280_of_spi_match[] = {
94         { .compatible = "bosch,bmp085", },
95         { .compatible = "bosch,bmp180", },
96         { .compatible = "bosch,bmp181", },
97         { .compatible = "bosch,bmp280", },
98         { .compatible = "bosch,bme280", },
99         { },
100 };
101 MODULE_DEVICE_TABLE(of, bmp280_of_spi_match);
102
103 static const struct spi_device_id bmp280_spi_id[] = {
104         { "bmp180", BMP180_CHIP_ID },
105         { "bmp181", BMP180_CHIP_ID },
106         { "bmp280", BMP280_CHIP_ID },
107         { "bme280", BME280_CHIP_ID },
108         { }
109 };
110 MODULE_DEVICE_TABLE(spi, bmp280_spi_id);
111
112 static struct spi_driver bmp280_spi_driver = {
113         .driver = {
114                 .name = "bmp280",
115                 .of_match_table = bmp280_of_spi_match,
116                 .pm = &bmp280_dev_pm_ops,
117         },
118         .id_table = bmp280_spi_id,
119         .probe = bmp280_spi_probe,
120         .remove = bmp280_spi_remove,
121 };
122 module_spi_driver(bmp280_spi_driver);
123
124 MODULE_DESCRIPTION("BMP280 SPI bus driver");
125 MODULE_LICENSE("GPL");