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 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 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 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 } 101 102 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 }; 118 119 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); 131 132 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