diff options
Diffstat (limited to 'drivers/input/touchscreen/cyttsp_spi.c')
-rw-r--r-- | drivers/input/touchscreen/cyttsp_spi.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/cyttsp_spi.c b/drivers/input/touchscreen/cyttsp_spi.c new file mode 100644 index 000000000000..9f263410407b --- /dev/null +++ b/drivers/input/touchscreen/cyttsp_spi.c | |||
@@ -0,0 +1,200 @@ | |||
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 | ||
8 | * | ||
9 | * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc. | ||
10 | * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org> | ||
11 | * | ||
12 | * This program is free software; you can redistribute it and/or | ||
13 | * modify it under the terms of the GNU General Public License | ||
14 | * version 2, and only version 2, as published by the | ||
15 | * Free Software Foundation. | ||
16 | * | ||
17 | * This program is distributed in the hope that it will be useful, | ||
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
20 | * GNU General Public License for more details. | ||
21 | * | ||
22 | * You should have received a copy of the GNU General Public License along | ||
23 | * with this program; if not, write to the Free Software Foundation, Inc., | ||
24 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. | ||
25 | * | ||
26 | * Contact Cypress Semiconductor at www.cypress.com <kev@cypress.com> | ||
27 | * | ||
28 | */ | ||
29 | |||
30 | #include "cyttsp_core.h" | ||
31 | |||
32 | #include <linux/delay.h> | ||
33 | #include <linux/input.h> | ||
34 | #include <linux/spi/spi.h> | ||
35 | |||
36 | #define CY_SPI_WR_OP 0x00 /* r/~w */ | ||
37 | #define CY_SPI_RD_OP 0x01 | ||
38 | #define CY_SPI_CMD_BYTES 4 | ||
39 | #define CY_SPI_SYNC_BYTE 2 | ||
40 | #define CY_SPI_SYNC_ACK1 0x62 /* from protocol v.2 */ | ||
41 | #define CY_SPI_SYNC_ACK2 0x9D /* from protocol v.2 */ | ||
42 | #define CY_SPI_DATA_SIZE 128 | ||
43 | #define CY_SPI_DATA_BUF_SIZE (CY_SPI_CMD_BYTES + CY_SPI_DATA_SIZE) | ||
44 | #define CY_SPI_BITS_PER_WORD 8 | ||
45 | |||
46 | static int cyttsp_spi_xfer(struct cyttsp *ts, | ||
47 | u8 op, u8 reg, u8 *buf, int length) | ||
48 | { | ||
49 | struct spi_device *spi = to_spi_device(ts->dev); | ||
50 | struct spi_message msg; | ||
51 | struct spi_transfer xfer[2]; | ||
52 | u8 *wr_buf = &ts->xfer_buf[0]; | ||
53 | u8 *rd_buf = &ts->xfer_buf[CY_SPI_DATA_BUF_SIZE]; | ||
54 | int retval; | ||
55 | int i; | ||
56 | |||
57 | if (length > CY_SPI_DATA_SIZE) { | ||
58 | dev_err(ts->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_DATA_BUF_SIZE); | ||
65 | |||
66 | wr_buf[0] = 0x00; /* header byte 0 */ | ||
67 | wr_buf[1] = 0xFF; /* header byte 1 */ | ||
68 | wr_buf[2] = reg; /* reg index */ | ||
69 | wr_buf[3] = op; /* r/~w */ | ||
70 | if (op == CY_SPI_WR_OP) | ||
71 | memcpy(wr_buf + CY_SPI_CMD_BYTES, buf, length); | ||
72 | |||
73 | memset(xfer, 0, sizeof(xfer)); | ||
74 | spi_message_init(&msg); | ||
75 | |||
76 | /* | ||
77 | We set both TX and RX buffers because Cypress TTSP | ||
78 | requires full duplex operation. | ||
79 | */ | ||
80 | xfer[0].tx_buf = wr_buf; | ||
81 | xfer[0].rx_buf = rd_buf; | ||
82 | switch (op) { | ||
83 | case CY_SPI_WR_OP: | ||
84 | xfer[0].len = length + CY_SPI_CMD_BYTES; | ||
85 | spi_message_add_tail(&xfer[0], &msg); | ||
86 | break; | ||
87 | |||
88 | case CY_SPI_RD_OP: | ||
89 | xfer[0].len = CY_SPI_CMD_BYTES; | ||
90 | spi_message_add_tail(&xfer[0], &msg); | ||
91 | |||
92 | xfer[1].rx_buf = buf; | ||
93 | xfer[1].len = length; | ||
94 | spi_message_add_tail(&xfer[1], &msg); | ||
95 | break; | ||
96 | |||
97 | default: | ||
98 | dev_err(ts->dev, "%s: bad operation code=%d\n", __func__, op); | ||
99 | return -EINVAL; | ||
100 | } | ||
101 | |||
102 | retval = spi_sync(spi, &msg); | ||
103 | if (retval < 0) { | ||
104 | dev_dbg(ts->dev, "%s: spi_sync() error %d, len=%d, op=%d\n", | ||
105 | __func__, retval, xfer[1].len, op); | ||
106 | |||
107 | /* | ||
108 | * do not return here since was a bad ACK sequence | ||
109 | * let the following ACK check handle any errors and | ||
110 | * allow silent retries | ||
111 | */ | ||
112 | } | ||
113 | |||
114 | if (rd_buf[CY_SPI_SYNC_BYTE] != CY_SPI_SYNC_ACK1 || | ||
115 | rd_buf[CY_SPI_SYNC_BYTE + 1] != CY_SPI_SYNC_ACK2) { | ||
116 | |||
117 | dev_dbg(ts->dev, "%s: operation %d failed\n", __func__, op); | ||
118 | |||
119 | for (i = 0; i < CY_SPI_CMD_BYTES; i++) | ||
120 | dev_dbg(ts->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(ts->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 cyttsp *ts, | ||
133 | u8 addr, u8 length, void *data) | ||
134 | { | ||
135 | return cyttsp_spi_xfer(ts, CY_SPI_RD_OP, addr, data, length); | ||
136 | } | ||
137 | |||
138 | static int cyttsp_spi_write_block_data(struct cyttsp *ts, | ||
139 | u8 addr, u8 length, const void *data) | ||
140 | { | ||
141 | return cyttsp_spi_xfer(ts, CY_SPI_WR_OP, addr, (void *)data, length); | ||
142 | } | ||
143 | |||
144 | static const struct cyttsp_bus_ops cyttsp_spi_bus_ops = { | ||
145 | .bustype = BUS_SPI, | ||
146 | .write = cyttsp_spi_write_block_data, | ||
147 | .read = cyttsp_spi_read_block_data, | ||
148 | }; | ||
149 | |||
150 | static int __devinit cyttsp_spi_probe(struct spi_device *spi) | ||
151 | { | ||
152 | struct cyttsp *ts; | ||
153 | int error; | ||
154 | |||
155 | /* Set up SPI*/ | ||
156 | spi->bits_per_word = CY_SPI_BITS_PER_WORD; | ||
157 | spi->mode = SPI_MODE_0; | ||
158 | error = spi_setup(spi); | ||
159 | if (error < 0) { | ||
160 | dev_err(&spi->dev, "%s: SPI setup error %d\n", | ||
161 | __func__, error); | ||
162 | return error; | ||
163 | } | ||
164 | |||
165 | ts = cyttsp_probe(&cyttsp_spi_bus_ops, &spi->dev, spi->irq, | ||
166 | CY_SPI_DATA_BUF_SIZE * 2); | ||
167 | if (IS_ERR(ts)) | ||
168 | return PTR_ERR(ts); | ||
169 | |||
170 | spi_set_drvdata(spi, ts); | ||
171 | |||
172 | return 0; | ||
173 | } | ||
174 | |||
175 | static int __devexit cyttsp_spi_remove(struct spi_device *spi) | ||
176 | { | ||
177 | struct cyttsp *ts = spi_get_drvdata(spi); | ||
178 | |||
179 | cyttsp_remove(ts); | ||
180 | |||
181 | return 0; | ||
182 | } | ||
183 | |||
184 | static struct spi_driver cyttsp_spi_driver = { | ||
185 | .driver = { | ||
186 | .name = CY_SPI_NAME, | ||
187 | .owner = THIS_MODULE, | ||
188 | .pm = &cyttsp_pm_ops, | ||
189 | }, | ||
190 | .probe = cyttsp_spi_probe, | ||
191 | .remove = __devexit_p(cyttsp_spi_remove), | ||
192 | }; | ||
193 | |||
194 | module_spi_driver(cyttsp_spi_driver); | ||
195 | |||
196 | MODULE_ALIAS("spi:cyttsp"); | ||
197 | MODULE_LICENSE("GPL"); | ||
198 | MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) SPI driver"); | ||
199 | MODULE_AUTHOR("Cypress"); | ||
200 | MODULE_ALIAS("spi:cyttsp"); | ||