-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Input: cyttsp4 - SPI driver for Cypress TMA4XX touchscreen devices
Cypress TrueTouch(tm) Standard Product controllers, Generation4 devices, SPI adapter module. This driver adds communication support with TTSP controller using SPI bus. Signed-off-by: Ferruh Yigit <fery@cypress.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Javier Martinez Canillas <javier@dowhile0.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
- Loading branch information
Ferruh Yigit
authored and
Dmitry Torokhov
committed
Jul 1, 2013
1 parent
4f9e868
commit 67bf12c
Showing
3 changed files
with
215 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,205 @@ | ||
/* | ||
* 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"); |