1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* 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
*
* 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, u16 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);
wr_buf[0] = op + (((reg >> 8) & 0x1) ? CY_SPI_A8_BIT : 0);
if (op == CY_SPI_WR_OP) {
wr_buf[1] = reg & 0xFF;
if (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,
u16 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,
u16 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);
return PTR_ERR_OR_ZERO(ts);
}
static void cyttsp4_spi_remove(struct spi_device *spi)
{
struct cyttsp4 *ts = spi_get_drvdata(spi);
cyttsp4_remove(ts);
}
static struct spi_driver cyttsp4_spi_driver = {
.driver = {
.name = CYTTSP4_SPI_NAME,
.pm = pm_ptr(&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");
|
