Input: dlink-dir685-touchkeys - fix a typo in driver name
[linux/fpc-iii.git] / drivers / input / touchscreen / cyttsp_spi.c
blob3c9d18b1b6efde5ee807ee8933ddbeda43bc747f
1 /*
2 * Source for:
3 * Cypress TrueTouch(TM) Standard Product (TTSP) SPI touchscreen driver.
4 * For use with Cypress Txx3xx parts.
5 * Supported parts include:
6 * CY8CTST341
7 * CY8CTMA340
9 * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
10 * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
11 * Copyright (C) 2013 Cypress Semiconductor
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * version 2, and only version 2, as published by the
16 * Free Software Foundation.
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * Contact Cypress Semiconductor at www.cypress.com <ttdrivers@cypress.com>
27 #include "cyttsp_core.h"
29 #include <linux/delay.h>
30 #include <linux/input.h>
31 #include <linux/spi/spi.h>
33 #define CY_SPI_WR_OP 0x00 /* r/~w */
34 #define CY_SPI_RD_OP 0x01
35 #define CY_SPI_CMD_BYTES 4
36 #define CY_SPI_SYNC_BYTE 2
37 #define CY_SPI_SYNC_ACK1 0x62 /* from protocol v.2 */
38 #define CY_SPI_SYNC_ACK2 0x9D /* from protocol v.2 */
39 #define CY_SPI_DATA_SIZE 128
40 #define CY_SPI_DATA_BUF_SIZE (CY_SPI_CMD_BYTES + CY_SPI_DATA_SIZE)
41 #define CY_SPI_BITS_PER_WORD 8
43 static int cyttsp_spi_xfer(struct device *dev, u8 *xfer_buf,
44 u8 op, u16 reg, u8 *buf, int length)
46 struct spi_device *spi = to_spi_device(dev);
47 struct spi_message msg;
48 struct spi_transfer xfer[2];
49 u8 *wr_buf = &xfer_buf[0];
50 u8 *rd_buf = &xfer_buf[CY_SPI_DATA_BUF_SIZE];
51 int retval;
52 int i;
54 if (length > CY_SPI_DATA_SIZE) {
55 dev_err(dev, "%s: length %d is too big.\n",
56 __func__, length);
57 return -EINVAL;
60 memset(wr_buf, 0, CY_SPI_DATA_BUF_SIZE);
61 memset(rd_buf, 0, CY_SPI_DATA_BUF_SIZE);
63 wr_buf[0] = 0x00; /* header byte 0 */
64 wr_buf[1] = 0xFF; /* header byte 1 */
65 wr_buf[2] = reg; /* reg index */
66 wr_buf[3] = op; /* r/~w */
67 if (op == CY_SPI_WR_OP)
68 memcpy(wr_buf + CY_SPI_CMD_BYTES, buf, length);
70 memset(xfer, 0, sizeof(xfer));
71 spi_message_init(&msg);
74 We set both TX and RX buffers because Cypress TTSP
75 requires full duplex operation.
77 xfer[0].tx_buf = wr_buf;
78 xfer[0].rx_buf = rd_buf;
79 switch (op) {
80 case CY_SPI_WR_OP:
81 xfer[0].len = length + CY_SPI_CMD_BYTES;
82 spi_message_add_tail(&xfer[0], &msg);
83 break;
85 case CY_SPI_RD_OP:
86 xfer[0].len = CY_SPI_CMD_BYTES;
87 spi_message_add_tail(&xfer[0], &msg);
89 xfer[1].rx_buf = buf;
90 xfer[1].len = length;
91 spi_message_add_tail(&xfer[1], &msg);
92 break;
94 default:
95 dev_err(dev, "%s: bad operation code=%d\n", __func__, op);
96 return -EINVAL;
99 retval = spi_sync(spi, &msg);
100 if (retval < 0) {
101 dev_dbg(dev, "%s: spi_sync() error %d, len=%d, op=%d\n",
102 __func__, retval, xfer[1].len, op);
105 * do not return here since was a bad ACK sequence
106 * let the following ACK check handle any errors and
107 * allow silent retries
111 if (rd_buf[CY_SPI_SYNC_BYTE] != CY_SPI_SYNC_ACK1 ||
112 rd_buf[CY_SPI_SYNC_BYTE + 1] != CY_SPI_SYNC_ACK2) {
113 dev_dbg(dev, "%s: operation %d failed\n", __func__, op);
115 for (i = 0; i < CY_SPI_CMD_BYTES; i++)
116 dev_dbg(dev, "%s: test rd_buf[%d]:0x%02x\n",
117 __func__, i, rd_buf[i]);
118 for (i = 0; i < length; i++)
119 dev_dbg(dev, "%s: test buf[%d]:0x%02x\n",
120 __func__, i, buf[i]);
122 return -EIO;
125 return 0;
128 static int cyttsp_spi_read_block_data(struct device *dev, u8 *xfer_buf,
129 u16 addr, u8 length, void *data)
131 return cyttsp_spi_xfer(dev, xfer_buf, CY_SPI_RD_OP, addr, data,
132 length);
135 static int cyttsp_spi_write_block_data(struct device *dev, u8 *xfer_buf,
136 u16 addr, u8 length, const void *data)
138 return cyttsp_spi_xfer(dev, xfer_buf, CY_SPI_WR_OP, addr, (void *)data,
139 length);
142 static const struct cyttsp_bus_ops cyttsp_spi_bus_ops = {
143 .bustype = BUS_SPI,
144 .write = cyttsp_spi_write_block_data,
145 .read = cyttsp_spi_read_block_data,
148 static int cyttsp_spi_probe(struct spi_device *spi)
150 struct cyttsp *ts;
151 int error;
153 /* Set up SPI*/
154 spi->bits_per_word = CY_SPI_BITS_PER_WORD;
155 spi->mode = SPI_MODE_0;
156 error = spi_setup(spi);
157 if (error < 0) {
158 dev_err(&spi->dev, "%s: SPI setup error %d\n",
159 __func__, error);
160 return error;
163 ts = cyttsp_probe(&cyttsp_spi_bus_ops, &spi->dev, spi->irq,
164 CY_SPI_DATA_BUF_SIZE * 2);
165 if (IS_ERR(ts))
166 return PTR_ERR(ts);
168 spi_set_drvdata(spi, ts);
170 return 0;
173 static struct spi_driver cyttsp_spi_driver = {
174 .driver = {
175 .name = CY_SPI_NAME,
176 .pm = &cyttsp_pm_ops,
178 .probe = cyttsp_spi_probe,
181 module_spi_driver(cyttsp_spi_driver);
183 MODULE_LICENSE("GPL");
184 MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) SPI driver");
185 MODULE_AUTHOR("Cypress");
186 MODULE_ALIAS("spi:cyttsp");