diff options
Diffstat (limited to 'drivers/input/touchscreen/cyttsp_spi.c')
| -rw-r--r-- | drivers/input/touchscreen/cyttsp_spi.c | 210 |
1 files changed, 210 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..9db5f8754d10 --- /dev/null +++ b/drivers/input/touchscreen/cyttsp_spi.c | |||
| @@ -0,0 +1,210 @@ | |||
| 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 | static int __init cyttsp_spi_init(void) | ||
| 195 | { | ||
| 196 | return spi_register_driver(&cyttsp_spi_driver); | ||
| 197 | } | ||
| 198 | module_init(cyttsp_spi_init); | ||
| 199 | |||
| 200 | static void __exit cyttsp_spi_exit(void) | ||
| 201 | { | ||
| 202 | spi_unregister_driver(&cyttsp_spi_driver); | ||
| 203 | } | ||
| 204 | module_exit(cyttsp_spi_exit); | ||
| 205 | |||
| 206 | MODULE_ALIAS("spi:cyttsp"); | ||
| 207 | MODULE_LICENSE("GPL"); | ||
| 208 | MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) SPI driver"); | ||
| 209 | MODULE_AUTHOR("Cypress"); | ||
| 210 | MODULE_ALIAS("spi:cyttsp"); | ||
