[mirror_ubuntu-artful-kernel.git] / drivers / input / touchscreen / cyttsp4_spi.c

/*
 * Source for:
 * Cypress TrueTouch(TM) Standard Product (TTSP) SPI touchscreen driver.
 * For use with Cypress Txx4xx parts.
 * Supported parts include:
 * TMA4XX
 * TMA1036
 *
 * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
 * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
 * Copyright (C) 2013 Cypress Semiconductor
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2, and only version 2, as published by the
 * Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Contact Cypress Semiconductor at www.cypress.com <ttdrivers@cypress.com>
 *
 */

#include "cyttsp4_core.h"

#include <linux/delay.h>
#include <linux/input.h>
#include <linux/spi/spi.h>

#define CY_SPI_WR_OP		0x00 /* r/~w */
#define CY_SPI_RD_OP		0x01
#define CY_SPI_BITS_PER_WORD	8
#define CY_SPI_A8_BIT		0x02
#define CY_SPI_WR_HEADER_BYTES	2
#define CY_SPI_RD_HEADER_BYTES	1
#define CY_SPI_CMD_BYTES	2
#define CY_SPI_SYNC_BYTE	0
#define CY_SPI_SYNC_ACK		0x62 /* from TRM *A protocol */
#define CY_SPI_DATA_SIZE	(2 * 256)

#define CY_SPI_DATA_BUF_SIZE	(CY_SPI_CMD_BYTES + CY_SPI_DATA_SIZE)

static int cyttsp_spi_xfer(struct device *dev, u8 *xfer_buf,
			   u8 op, u8 reg, u8 *buf, int length)
{
	struct spi_device *spi = to_spi_device(dev);
	struct spi_message msg;
	struct spi_transfer xfer[2];
	u8 *wr_buf = &xfer_buf[0];
	u8 rd_buf[CY_SPI_CMD_BYTES];
	int retval;
	int i;

	if (length > CY_SPI_DATA_SIZE) {
		dev_err(dev, "%s: length %d is too big.\n",
			__func__, length);
		return -EINVAL;
	}

	memset(wr_buf, 0, CY_SPI_DATA_BUF_SIZE);
	memset(rd_buf, 0, CY_SPI_CMD_BYTES);

	if (reg > 255)
		wr_buf[0] = op + CY_SPI_A8_BIT;
	else
		wr_buf[0] = op;
	if (op == CY_SPI_WR_OP)
		wr_buf[1] = reg % 256;
	if (op == CY_SPI_WR_OP && length > 0)
		memcpy(wr_buf + CY_SPI_CMD_BYTES, buf, length);

	memset(xfer, 0, sizeof(xfer));
	spi_message_init(&msg);

	/*
	  We set both TX and RX buffers because Cypress TTSP
	  requires full duplex operation.
	*/
	xfer[0].tx_buf = wr_buf;
	xfer[0].rx_buf = rd_buf;
	switch (op) {
	case CY_SPI_WR_OP:
		xfer[0].len = length + CY_SPI_CMD_BYTES;
		spi_message_add_tail(&xfer[0], &msg);
		break;

	case CY_SPI_RD_OP:
		xfer[0].len = CY_SPI_RD_HEADER_BYTES;
		spi_message_add_tail(&xfer[0], &msg);

		xfer[1].rx_buf = buf;
		xfer[1].len = length;
		spi_message_add_tail(&xfer[1], &msg);
		break;

	default:
		dev_err(dev, "%s: bad operation code=%d\n", __func__, op);
		return -EINVAL;
	}

	retval = spi_sync(spi, &msg);
	if (retval < 0) {
		dev_dbg(dev, "%s: spi_sync() error %d, len=%d, op=%d\n",
			__func__, retval, xfer[1].len, op);

		/*
		 * do not return here since was a bad ACK sequence
		 * let the following ACK check handle any errors and
		 * allow silent retries
		 */
	}

	if (rd_buf[CY_SPI_SYNC_BYTE] != CY_SPI_SYNC_ACK) {
		dev_dbg(dev, "%s: operation %d failed\n", __func__, op);

		for (i = 0; i < CY_SPI_CMD_BYTES; i++)
			dev_dbg(dev, "%s: test rd_buf[%d]:0x%02x\n",
				__func__, i, rd_buf[i]);
		for (i = 0; i < length; i++)
			dev_dbg(dev, "%s: test buf[%d]:0x%02x\n",
				__func__, i, buf[i]);

		return -EIO;
	}

	return 0;
}

static int cyttsp_spi_read_block_data(struct device *dev, u8 *xfer_buf,
				      u8 addr, u8 length, void *data)
{
	int rc;

	rc = cyttsp_spi_xfer(dev, xfer_buf, CY_SPI_WR_OP, addr, NULL, 0);
	if (rc)
		return rc;
	else
		return cyttsp_spi_xfer(dev, xfer_buf, CY_SPI_RD_OP, addr, data,
				length);
}

static int cyttsp_spi_write_block_data(struct device *dev, u8 *xfer_buf,
				       u8 addr, u8 length, const void *data)
{
	return cyttsp_spi_xfer(dev, xfer_buf, CY_SPI_WR_OP, addr, (void *)data,
			length);
}

static const struct cyttsp4_bus_ops cyttsp_spi_bus_ops = {
	.bustype	= BUS_SPI,
	.write		= cyttsp_spi_write_block_data,
	.read		= cyttsp_spi_read_block_data,
};

static int cyttsp4_spi_probe(struct spi_device *spi)
{
	struct cyttsp4 *ts;
	int error;

	/* Set up SPI*/
	spi->bits_per_word = CY_SPI_BITS_PER_WORD;
	spi->mode = SPI_MODE_0;
	error = spi_setup(spi);
	if (error < 0) {
		dev_err(&spi->dev, "%s: SPI setup error %d\n",
			__func__, error);
		return error;
	}

	ts = cyttsp4_probe(&cyttsp_spi_bus_ops, &spi->dev, spi->irq,
			  CY_SPI_DATA_BUF_SIZE);

	if (IS_ERR(ts))
		return PTR_ERR(ts);

	return 0;
}

static int cyttsp4_spi_remove(struct spi_device *spi)
{
	struct cyttsp4 *ts = spi_get_drvdata(spi);
	cyttsp4_remove(ts);

	return 0;
}

static struct spi_driver cyttsp4_spi_driver = {
	.driver = {
		.name	= CYTTSP4_SPI_NAME,
		.owner	= THIS_MODULE,
		.pm	= &cyttsp4_pm_ops,
	},
	.probe  = cyttsp4_spi_probe,
	.remove = cyttsp4_spi_remove,
};

module_spi_driver(cyttsp4_spi_driver);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) SPI driver");
MODULE_AUTHOR("Cypress");
MODULE_ALIAS("spi:cyttsp4");
Commit	Line	Data
67bf12ca FY	1	/*
	2	* Source for:
	3	* Cypress TrueTouch(TM) Standard Product (TTSP) SPI touchscreen driver.
	4	* For use with Cypress Txx4xx parts.
	5	* Supported parts include:
	6	* TMA4XX
	7	* TMA1036
	8	*
	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
	12	*
	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.
	17	*
	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.
	22	*
	23	* Contact Cypress Semiconductor at www.cypress.com <ttdrivers@cypress.com>
	24	*
	25	*/
	26
	27	#include "cyttsp4_core.h"
	28
	29	#include <linux/delay.h>
	30	#include <linux/input.h>
	31	#include <linux/spi/spi.h>
	32
	33	#define CY_SPI_WR_OP 0x00 /* r/~w */
	34	#define CY_SPI_RD_OP 0x01
	35	#define CY_SPI_BITS_PER_WORD 8
	36	#define CY_SPI_A8_BIT 0x02
	37	#define CY_SPI_WR_HEADER_BYTES 2
	38	#define CY_SPI_RD_HEADER_BYTES 1
	39	#define CY_SPI_CMD_BYTES 2
	40	#define CY_SPI_SYNC_BYTE 0
	41	#define CY_SPI_SYNC_ACK 0x62 /* from TRM A protocol /
	42	#define CY_SPI_DATA_SIZE (2 * 256)
	43
	44	#define CY_SPI_DATA_BUF_SIZE (CY_SPI_CMD_BYTES + CY_SPI_DATA_SIZE)
	45
	46	static int cyttsp_spi_xfer(struct device dev, u8 xfer_buf,
	47	u8 op, u8 reg, u8 *buf, int length)
	48	{
	49	struct spi_device *spi = to_spi_device(dev);
	50	struct spi_message msg;
	51	struct spi_transfer xfer[2];
	52	u8 *wr_buf = &xfer_buf[0];
	53	u8 rd_buf[CY_SPI_CMD_BYTES];
	54	int retval;
	55	int i;
	56
	57	if (length > CY_SPI_DATA_SIZE) {
	58	dev_err(dev, "%s: length %d is too big.\n",
	59	__func__, length);
	60	return -EINVAL;
	61	}
	62
	63	memset(wr_buf, 0, CY_SPI_DATA_BUF_SIZE);
	64	memset(rd_buf, 0, CY_SPI_CMD_BYTES);
65
66	if (reg > 255)
67	wr_buf[0] = op + CY_SPI_A8_BIT;
68	else
69	wr_buf[0] = op;
70	if (op == CY_SPI_WR_OP)
71	wr_buf[1] = reg % 256;
72	if (op == CY_SPI_WR_OP && length > 0)
73	memcpy(wr_buf + CY_SPI_CMD_BYTES, buf, length);
74
75	memset(xfer, 0, sizeof(xfer));
76	spi_message_init(&msg);
77
78	/*
79	We set both TX and RX buffers because Cypress TTSP
80	requires full duplex operation.
81	*/
82	xfer[0].tx_buf = wr_buf;
83	xfer[0].rx_buf = rd_buf;
84	switch (op) {
85	case CY_SPI_WR_OP:
86	xfer[0].len = length + CY_SPI_CMD_BYTES;
87	spi_message_add_tail(&xfer[0], &msg);
88	break;
89
90	case CY_SPI_RD_OP:
91	xfer[0].len = CY_SPI_RD_HEADER_BYTES;
92	spi_message_add_tail(&xfer[0], &msg);
93
94	xfer[1].rx_buf = buf;
95	xfer[1].len = length;
96	spi_message_add_tail(&xfer[1], &msg);
97	break;
98
99	default:
100	dev_err(dev, "%s: bad operation code=%d\n", __func__, op);
101	return -EINVAL;
102	}
103
104	retval = spi_sync(spi, &msg);
105	if (retval < 0) {
106	dev_dbg(dev, "%s: spi_sync() error %d, len=%d, op=%d\n",
107	__func__, retval, xfer[1].len, op);
108
109	/*
110	* do not return here since was a bad ACK sequence
111	* let the following ACK check handle any errors and
112	* allow silent retries
113	*/
114	}
115
116	if (rd_buf[CY_SPI_SYNC_BYTE] != CY_SPI_SYNC_ACK) {
117	dev_dbg(dev, "%s: operation %d failed\n", __func__, op);
118
119	for (i = 0; i < CY_SPI_CMD_BYTES; i++)
120	dev_dbg(dev, "%s: test rd_buf[%d]:0x%02x\n",
121	__func__, i, rd_buf[i]);
122	for (i = 0; i < length; i++)
123	dev_dbg(dev, "%s: test buf[%d]:0x%02x\n",
124	__func__, i, buf[i]);
125
126	return -EIO;
127	}
128
129	return 0;
130	}
131
132	static int cyttsp_spi_read_block_data(struct device dev, u8 xfer_buf,
133	u8 addr, u8 length, void *data)
134	{
135	int rc;
136
137	rc = cyttsp_spi_xfer(dev, xfer_buf, CY_SPI_WR_OP, addr, NULL, 0);
138	if (rc)
139	return rc;
140	else
141	return cyttsp_spi_xfer(dev, xfer_buf, CY_SPI_RD_OP, addr, data,
142	length);
143	}
144
145	static int cyttsp_spi_write_block_data(struct device dev, u8 xfer_buf,
146	u8 addr, u8 length, const void *data)
147	{
148	return cyttsp_spi_xfer(dev, xfer_buf, CY_SPI_WR_OP, addr, (void *)data,
149	length);
150	}
151
152	static const struct cyttsp4_bus_ops cyttsp_spi_bus_ops = {
153	.bustype = BUS_SPI,
154	.write = cyttsp_spi_write_block_data,
155	.read = cyttsp_spi_read_block_data,
156	};
157
158	static int cyttsp4_spi_probe(struct spi_device *spi)
159	{
160	struct cyttsp4 *ts;
161	int error;
162
163	/* Set up SPI*/
164	spi->bits_per_word = CY_SPI_BITS_PER_WORD;
165	spi->mode = SPI_MODE_0;
166	error = spi_setup(spi);
167	if (error < 0) {
168	dev_err(&spi->dev, "%s: SPI setup error %d\n",
169	__func__, error);
170	return error;
171	}
172
173	ts = cyttsp4_probe(&cyttsp_spi_bus_ops, &spi->dev, spi->irq,
174	CY_SPI_DATA_BUF_SIZE);
175
176	if (IS_ERR(ts))
177	return PTR_ERR(ts);
178
179	return 0;
180	}
181
182	static int cyttsp4_spi_remove(struct spi_device *spi)
183	{
184	struct cyttsp4 *ts = spi_get_drvdata(spi);
185	cyttsp4_remove(ts);
186
187	return 0;
188	}
189
190	static struct spi_driver cyttsp4_spi_driver = {
191	.driver = {
192	.name = CYTTSP4_SPI_NAME,
193	.owner = THIS_MODULE,
194	.pm = &cyttsp4_pm_ops,
195	},
196	.probe = cyttsp4_spi_probe,
197	.remove = cyttsp4_spi_remove,
198	};
199
200	module_spi_driver(cyttsp4_spi_driver);
201
202	MODULE_LICENSE("GPL");
203	MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) SPI driver");
204	MODULE_AUTHOR("Cypress");
205	MODULE_ALIAS("spi:cyttsp4");