drivers/input/touchscreen/cyttsp_i2c.c

   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");