1 /* 2 * STMicroelectronics hts221 i2c driver 3 * 4 * Copyright 2016 STMicroelectronics Inc. 5 * 6 * Lorenzo Bianconi <lorenzo.bianconi@st.com> 7 * 8 * Licensed under the GPL-2. 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/acpi.h> 14 #include <linux/i2c.h> 15 #include <linux/slab.h> 16 #include "hts221.h" 17 18 #define I2C_AUTO_INCREMENT 0x80 19 20 static int hts221_i2c_read(struct device *dev, u8 addr, int len, u8 *data) 21 { 22 struct i2c_msg msg[2]; 23 struct i2c_client *client = to_i2c_client(dev); 24 25 if (len > 1) 26 addr |= I2C_AUTO_INCREMENT; 27 28 msg[0].addr = client->addr; 29 msg[0].flags = client->flags; 30 msg[0].len = 1; 31 msg[0].buf = &addr; 32 33 msg[1].addr = client->addr; 34 msg[1].flags = client->flags | I2C_M_RD; 35 msg[1].len = len; 36 msg[1].buf = data; 37 38 return i2c_transfer(client->adapter, msg, 2); 39 } 40 41 static int hts221_i2c_write(struct device *dev, u8 addr, int len, u8 *data) 42 { 43 u8 send[len + 1]; 44 struct i2c_msg msg; 45 struct i2c_client *client = to_i2c_client(dev); 46 47 if (len > 1) 48 addr |= I2C_AUTO_INCREMENT; 49 50 send[0] = addr; 51 memcpy(&send[1], data, len * sizeof(u8)); 52 53 msg.addr = client->addr; 54 msg.flags = client->flags; 55 msg.len = len + 1; 56 msg.buf = send; 57 58 return i2c_transfer(client->adapter, &msg, 1); 59 } 60 61 static const struct hts221_transfer_function hts221_transfer_fn = { 62 .read = hts221_i2c_read, 63 .write = hts221_i2c_write, 64 }; 65 66 static int hts221_i2c_probe(struct i2c_client *client, 67 const struct i2c_device_id *id) 68 { 69 return hts221_probe(&client->dev, client->irq, 70 client->name, &hts221_transfer_fn); 71 } 72 73 static const struct acpi_device_id hts221_acpi_match[] = { 74 {"SMO9100", 0}, 75 { }, 76 }; 77 MODULE_DEVICE_TABLE(acpi, hts221_acpi_match); 78 79 static const struct of_device_id hts221_i2c_of_match[] = { 80 { .compatible = "st,hts221", }, 81 {}, 82 }; 83 MODULE_DEVICE_TABLE(of, hts221_i2c_of_match); 84 85 static const struct i2c_device_id hts221_i2c_id_table[] = { 86 { HTS221_DEV_NAME }, 87 {}, 88 }; 89 MODULE_DEVICE_TABLE(i2c, hts221_i2c_id_table); 90 91 static struct i2c_driver hts221_driver = { 92 .driver = { 93 .name = "hts221_i2c", 94 .pm = &hts221_pm_ops, 95 .of_match_table = of_match_ptr(hts221_i2c_of_match), 96 .acpi_match_table = ACPI_PTR(hts221_acpi_match), 97 }, 98 .probe = hts221_i2c_probe, 99 .id_table = hts221_i2c_id_table, 100 }; 101 module_i2c_driver(hts221_driver); 102 103 MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>"); 104 MODULE_DESCRIPTION("STMicroelectronics hts221 i2c driver"); 105 MODULE_LICENSE("GPL v2"); 106