1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * cyttsp_i2c.c 4 * Cypress TrueTouch(TM) Standard Product (TTSP) I2C touchscreen driver. 5 * For use with Cypress Txx3xx parts. 6 * Supported parts include: 7 * CY8CTST341 8 * CY8CTMA340 9 * 10 * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc. 11 * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org> 12 * 13 * Contact Cypress Semiconductor at www.cypress.com <ttdrivers@cypress.com> 14 */ 15 16 #include "cyttsp_core.h" 17 18 #include <linux/i2c.h> 19 #include <linux/input.h> 20 21 #define CY_I2C_NAME "cyttsp-i2c" 22 23 #define CY_I2C_DATA_SIZE 128 24 25 static int cyttsp_i2c_read_block_data(struct device *dev, u8 *xfer_buf, 26 u16 addr, u8 length, void *values) 27 { 28 struct i2c_client *client = to_i2c_client(dev); 29 u8 client_addr = client->addr | ((addr >> 8) & 0x1); 30 u8 addr_lo = addr & 0xFF; 31 struct i2c_msg msgs[] = { 32 { 33 .addr = client_addr, 34 .flags = 0, 35 .len = 1, 36 .buf = &addr_lo, 37 }, 38 { 39 .addr = client_addr, 40 .flags = I2C_M_RD, 41 .len = length, 42 .buf = values, 43 }, 44 }; 45 int retval; 46 47 retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); 48 if (retval < 0) 49 return retval; 50 51 return retval != ARRAY_SIZE(msgs) ? -EIO : 0; 52 } 53 54 static int cyttsp_i2c_write_block_data(struct device *dev, u8 *xfer_buf, 55 u16 addr, u8 length, const void *values) 56 { 57 struct i2c_client *client = to_i2c_client(dev); 58 u8 client_addr = client->addr | ((addr >> 8) & 0x1); 59 u8 addr_lo = addr & 0xFF; 60 struct i2c_msg msgs[] = { 61 { 62 .addr = client_addr, 63 .flags = 0, 64 .len = length + 1, 65 .buf = xfer_buf, 66 }, 67 }; 68 int retval; 69 70 xfer_buf[0] = addr_lo; 71 memcpy(&xfer_buf[1], values, length); 72 73 retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); 74 if (retval < 0) 75 return retval; 76 77 return retval != ARRAY_SIZE(msgs) ? -EIO : 0; 78 } 79 80 static const struct cyttsp_bus_ops cyttsp_i2c_bus_ops = { 81 .bustype = BUS_I2C, 82 .write = cyttsp_i2c_write_block_data, 83 .read = cyttsp_i2c_read_block_data, 84 }; 85 86 static int cyttsp_i2c_probe(struct i2c_client *client) 87 { 88 struct cyttsp *ts; 89 90 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { 91 dev_err(&client->dev, "I2C functionality not Supported\n"); 92 return -EIO; 93 } 94 95 ts = cyttsp_probe(&cyttsp_i2c_bus_ops, &client->dev, client->irq, 96 CY_I2C_DATA_SIZE); 97 98 if (IS_ERR(ts)) 99 return PTR_ERR(ts); 100 101 i2c_set_clientdata(client, ts); 102 return 0; 103 } 104 105 static const struct i2c_device_id cyttsp_i2c_id[] = { 106 { CY_I2C_NAME }, 107 { } 108 }; 109 MODULE_DEVICE_TABLE(i2c, cyttsp_i2c_id); 110 111 static const struct of_device_id cyttsp_of_i2c_match[] = { 112 { .compatible = "cypress,cy8ctma340", }, 113 { .compatible = "cypress,cy8ctst341", }, 114 { /* sentinel */ } 115 }; 116 MODULE_DEVICE_TABLE(of, cyttsp_of_i2c_match); 117 118 static struct i2c_driver cyttsp_i2c_driver = { 119 .driver = { 120 .name = CY_I2C_NAME, 121 .pm = pm_sleep_ptr(&cyttsp_pm_ops), 122 .of_match_table = cyttsp_of_i2c_match, 123 }, 124 .probe = cyttsp_i2c_probe, 125 .id_table = cyttsp_i2c_id, 126 }; 127 128 module_i2c_driver(cyttsp_i2c_driver); 129 130 MODULE_LICENSE("GPL"); 131 MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) I2C driver"); 132 MODULE_AUTHOR("Cypress"); 133