1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Murata ZPA2326 SPI pressure and temperature sensor driver
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (c) 2016 Parrot S.A.
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Author: Gregor Boirie <gregor.boirie@parrot.com>
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/module.h>
11*4882a593Smuzhiyun #include <linux/regmap.h>
12*4882a593Smuzhiyun #include <linux/spi/spi.h>
13*4882a593Smuzhiyun #include <linux/mod_devicetable.h>
14*4882a593Smuzhiyun #include "zpa2326.h"
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun /*
17*4882a593Smuzhiyun * read_flag_mask:
18*4882a593Smuzhiyun * - address bit 7 must be set to request a register read operation
19*4882a593Smuzhiyun * - address bit 6 must be set to request register address auto increment
20*4882a593Smuzhiyun */
21*4882a593Smuzhiyun static const struct regmap_config zpa2326_regmap_spi_config = {
22*4882a593Smuzhiyun .reg_bits = 8,
23*4882a593Smuzhiyun .val_bits = 8,
24*4882a593Smuzhiyun .writeable_reg = zpa2326_isreg_writeable,
25*4882a593Smuzhiyun .readable_reg = zpa2326_isreg_readable,
26*4882a593Smuzhiyun .precious_reg = zpa2326_isreg_precious,
27*4882a593Smuzhiyun .max_register = ZPA2326_TEMP_OUT_H_REG,
28*4882a593Smuzhiyun .read_flag_mask = BIT(7) | BIT(6),
29*4882a593Smuzhiyun .cache_type = REGCACHE_NONE,
30*4882a593Smuzhiyun };
31*4882a593Smuzhiyun
zpa2326_probe_spi(struct spi_device * spi)32*4882a593Smuzhiyun static int zpa2326_probe_spi(struct spi_device *spi)
33*4882a593Smuzhiyun {
34*4882a593Smuzhiyun struct regmap *regmap;
35*4882a593Smuzhiyun int err;
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun regmap = devm_regmap_init_spi(spi, &zpa2326_regmap_spi_config);
38*4882a593Smuzhiyun if (IS_ERR(regmap)) {
39*4882a593Smuzhiyun dev_err(&spi->dev, "failed to init registers map");
40*4882a593Smuzhiyun return PTR_ERR(regmap);
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun /*
44*4882a593Smuzhiyun * Enforce SPI slave settings to prevent from DT misconfiguration.
45*4882a593Smuzhiyun *
46*4882a593Smuzhiyun * Clock is idle high. Sampling happens on trailing edge, i.e., rising
47*4882a593Smuzhiyun * edge. Maximum bus frequency is 1 MHz. Registers are 8 bits wide.
48*4882a593Smuzhiyun */
49*4882a593Smuzhiyun spi->mode = SPI_MODE_3;
50*4882a593Smuzhiyun spi->max_speed_hz = min(spi->max_speed_hz, 1000000U);
51*4882a593Smuzhiyun spi->bits_per_word = 8;
52*4882a593Smuzhiyun err = spi_setup(spi);
53*4882a593Smuzhiyun if (err < 0)
54*4882a593Smuzhiyun return err;
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun return zpa2326_probe(&spi->dev, spi_get_device_id(spi)->name,
57*4882a593Smuzhiyun spi->irq, ZPA2326_DEVICE_ID, regmap);
58*4882a593Smuzhiyun }
59*4882a593Smuzhiyun
zpa2326_remove_spi(struct spi_device * spi)60*4882a593Smuzhiyun static int zpa2326_remove_spi(struct spi_device *spi)
61*4882a593Smuzhiyun {
62*4882a593Smuzhiyun zpa2326_remove(&spi->dev);
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun return 0;
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun static const struct spi_device_id zpa2326_spi_ids[] = {
68*4882a593Smuzhiyun { "zpa2326", 0 },
69*4882a593Smuzhiyun { },
70*4882a593Smuzhiyun };
71*4882a593Smuzhiyun MODULE_DEVICE_TABLE(spi, zpa2326_spi_ids);
72*4882a593Smuzhiyun
73*4882a593Smuzhiyun static const struct of_device_id zpa2326_spi_matches[] = {
74*4882a593Smuzhiyun { .compatible = "murata,zpa2326" },
75*4882a593Smuzhiyun { }
76*4882a593Smuzhiyun };
77*4882a593Smuzhiyun MODULE_DEVICE_TABLE(of, zpa2326_spi_matches);
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun static struct spi_driver zpa2326_spi_driver = {
80*4882a593Smuzhiyun .driver = {
81*4882a593Smuzhiyun .name = "zpa2326-spi",
82*4882a593Smuzhiyun .of_match_table = zpa2326_spi_matches,
83*4882a593Smuzhiyun .pm = ZPA2326_PM_OPS,
84*4882a593Smuzhiyun },
85*4882a593Smuzhiyun .probe = zpa2326_probe_spi,
86*4882a593Smuzhiyun .remove = zpa2326_remove_spi,
87*4882a593Smuzhiyun .id_table = zpa2326_spi_ids,
88*4882a593Smuzhiyun };
89*4882a593Smuzhiyun module_spi_driver(zpa2326_spi_driver);
90*4882a593Smuzhiyun
91*4882a593Smuzhiyun MODULE_AUTHOR("Gregor Boirie <gregor.boirie@parrot.com>");
92*4882a593Smuzhiyun MODULE_DESCRIPTION("SPI driver for Murata ZPA2326 pressure sensor");
93*4882a593Smuzhiyun MODULE_LICENSE("GPL v2");
94