1 /*
2 * tps65912-spi.c -- SPI access for TI TPS65912x PMIC
3 *
4 * Copyright 2011 Texas Instruments Inc.
5 *
6 * Author: Margarita Olaya Cabrera <magi@slimlogic.co.uk>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 *
13 * This driver is based on wm8350 implementation.
14 */
15
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/gpio.h>
21 #include <linux/spi/spi.h>
22 #include <linux/mfd/core.h>
23 #include <linux/mfd/tps65912.h>
24
tps65912_spi_write(struct tps65912 * tps65912,u8 addr,int bytes,void * src)25 static int tps65912_spi_write(struct tps65912 *tps65912, u8 addr,
26 int bytes, void *src)
27 {
28 struct spi_device *spi = tps65912->control_data;
29 u8 *data = (u8 *) src;
30 int ret;
31 /* bit 23 is the read/write bit */
32 unsigned long spi_data = 1 << 23 | addr << 15 | *data;
33 struct spi_transfer xfer;
34 struct spi_message msg;
35 u32 tx_buf;
36
37 tx_buf = spi_data;
38
39 xfer.tx_buf = &tx_buf;
40 xfer.rx_buf = NULL;
41 xfer.len = sizeof(unsigned long);
42 xfer.bits_per_word = 24;
43
44 spi_message_init(&msg);
45 spi_message_add_tail(&xfer, &msg);
46
47 ret = spi_sync(spi, &msg);
48 return ret;
49 }
50
tps65912_spi_read(struct tps65912 * tps65912,u8 addr,int bytes,void * dest)51 static int tps65912_spi_read(struct tps65912 *tps65912, u8 addr,
52 int bytes, void *dest)
53 {
54 struct spi_device *spi = tps65912->control_data;
55 /* bit 23 is the read/write bit */
56 unsigned long spi_data = 0 << 23 | addr << 15;
57 struct spi_transfer xfer;
58 struct spi_message msg;
59 int ret;
60 u8 *data = (u8 *) dest;
61 u32 tx_buf, rx_buf;
62
63 tx_buf = spi_data;
64 rx_buf = 0;
65
66 xfer.tx_buf = &tx_buf;
67 xfer.rx_buf = &rx_buf;
68 xfer.len = sizeof(unsigned long);
69 xfer.bits_per_word = 24;
70
71 spi_message_init(&msg);
72 spi_message_add_tail(&xfer, &msg);
73
74 if (spi == NULL)
75 return 0;
76
77 ret = spi_sync(spi, &msg);
78 if (ret == 0)
79 *data = (u8) (rx_buf & 0xFF);
80 return ret;
81 }
82
tps65912_spi_probe(struct spi_device * spi)83 static int tps65912_spi_probe(struct spi_device *spi)
84 {
85 struct tps65912 *tps65912;
86
87 tps65912 = devm_kzalloc(&spi->dev,
88 sizeof(struct tps65912), GFP_KERNEL);
89 if (tps65912 == NULL)
90 return -ENOMEM;
91
92 tps65912->dev = &spi->dev;
93 tps65912->control_data = spi;
94 tps65912->read = tps65912_spi_read;
95 tps65912->write = tps65912_spi_write;
96
97 spi_set_drvdata(spi, tps65912);
98
99 return tps65912_device_init(tps65912);
100 }
101
tps65912_spi_remove(struct spi_device * spi)102 static int tps65912_spi_remove(struct spi_device *spi)
103 {
104 struct tps65912 *tps65912 = spi_get_drvdata(spi);
105
106 tps65912_device_exit(tps65912);
107
108 return 0;
109 }
110
111 static struct spi_driver tps65912_spi_driver = {
112 .driver = {
113 .name = "tps65912",
114 },
115 .probe = tps65912_spi_probe,
116 .remove = tps65912_spi_remove,
117 };
118
tps65912_spi_init(void)119 static int __init tps65912_spi_init(void)
120 {
121 int ret;
122
123 ret = spi_register_driver(&tps65912_spi_driver);
124 if (ret != 0)
125 pr_err("Failed to register TPS65912 SPI driver: %d\n", ret);
126
127 return 0;
128 }
129 /* init early so consumer devices can complete system boot */
130 subsys_initcall(tps65912_spi_init);
131
tps65912_spi_exit(void)132 static void __exit tps65912_spi_exit(void)
133 {
134 spi_unregister_driver(&tps65912_spi_driver);
135 }
136 module_exit(tps65912_spi_exit);
137
138 MODULE_AUTHOR("Margarita Olaya <magi@slimlogic.co.uk>");
139 MODULE_DESCRIPTION("SPI support for TPS65912 chip family mfd");
140 MODULE_LICENSE("GPL");
141