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-rw-r--r--drivers/input/misc/ad714x-spi.c115
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");