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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/input/misc/ad714x-spi.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/input/misc/ad714x-spi.c')
-rw-r--r-- | drivers/input/misc/ad714x-spi.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c new file mode 100644 index 000000000..7d3bf4346 --- /dev/null +++ b/drivers/input/misc/ad714x-spi.c @@ -0,0 +1,115 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * AD714X CapTouch Programmable Controller driver (SPI bus) + * + * Copyright 2009-2011 Analog Devices Inc. + */ + +#include <linux/input.h> /* BUS_SPI */ +#include <linux/module.h> +#include <linux/spi/spi.h> +#include <linux/pm.h> +#include <linux/types.h> +#include "ad714x.h" + +#define AD714x_SPI_CMD_PREFIX 0xE000 /* bits 15:11 */ +#define AD714x_SPI_READ BIT(10) + +static int __maybe_unused ad714x_spi_suspend(struct device *dev) +{ + return ad714x_disable(spi_get_drvdata(to_spi_device(dev))); +} + +static int __maybe_unused ad714x_spi_resume(struct device *dev) +{ + return ad714x_enable(spi_get_drvdata(to_spi_device(dev))); +} + +static SIMPLE_DEV_PM_OPS(ad714x_spi_pm, ad714x_spi_suspend, ad714x_spi_resume); + +static int ad714x_spi_read(struct ad714x_chip *chip, + unsigned short reg, unsigned short *data, size_t len) +{ + struct spi_device *spi = to_spi_device(chip->dev); + struct spi_message message; + struct spi_transfer xfer[2]; + int i; + int error; + + spi_message_init(&message); + memset(xfer, 0, sizeof(xfer)); + + chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX | + AD714x_SPI_READ | reg); + xfer[0].tx_buf = &chip->xfer_buf[0]; + xfer[0].len = sizeof(chip->xfer_buf[0]); + spi_message_add_tail(&xfer[0], &message); + + xfer[1].rx_buf = &chip->xfer_buf[1]; + xfer[1].len = sizeof(chip->xfer_buf[1]) * len; + spi_message_add_tail(&xfer[1], &message); + + error = spi_sync(spi, &message); + if (unlikely(error)) { + dev_err(chip->dev, "SPI read error: %d\n", error); + return error; + } + + for (i = 0; i < len; i++) + data[i] = be16_to_cpu(chip->xfer_buf[i + 1]); + + return 0; +} + +static int ad714x_spi_write(struct ad714x_chip *chip, + unsigned short reg, unsigned short data) +{ + struct spi_device *spi = to_spi_device(chip->dev); + int error; + + chip->xfer_buf[0] = cpu_to_be16(AD714x_SPI_CMD_PREFIX | reg); + chip->xfer_buf[1] = cpu_to_be16(data); + + error = spi_write(spi, (u8 *)chip->xfer_buf, + 2 * sizeof(*chip->xfer_buf)); + if (unlikely(error)) { + dev_err(chip->dev, "SPI write error: %d\n", error); + return error; + } + + return 0; +} + +static int ad714x_spi_probe(struct spi_device *spi) +{ + struct ad714x_chip *chip; + int err; + + spi->bits_per_word = 8; + err = spi_setup(spi); + if (err < 0) + return err; + + chip = ad714x_probe(&spi->dev, BUS_SPI, spi->irq, + ad714x_spi_read, ad714x_spi_write); + if (IS_ERR(chip)) + return PTR_ERR(chip); + + spi_set_drvdata(spi, chip); + + return 0; +} + +static struct spi_driver ad714x_spi_driver = { + .driver = { + .name = "ad714x_captouch", + .pm = &ad714x_spi_pm, + }, + .probe = ad714x_spi_probe, +}; + +module_spi_driver(ad714x_spi_driver); + +MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor SPI Bus Driver"); +MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); +MODULE_LICENSE("GPL"); |