Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / input / misc / ad714x-spi.c

diff --git a/kernel/drivers/input/misc/ad714x-spi.c b/kernel/drivers/input/misc/ad714x-spi.c
new file mode 100644 (file)
index 0000000..a79e50b
--- /dev/null
+++ b/kernel/drivers/input/misc/ad714x-spi.c
@@ -0,0 +1,127 @@
+/*
+ * AD714X CapTouch Programmable Controller driver (SPI bus)
+ *
+ * Copyright 2009-2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#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 int ad714x_spi_remove(struct spi_device *spi)
+{
+       struct ad714x_chip *chip = spi_get_drvdata(spi);
+
+       ad714x_remove(chip);
+
+       return 0;
+}
+
+static struct spi_driver ad714x_spi_driver = {
+       .driver = {
+               .name   = "ad714x_captouch",
+               .owner  = THIS_MODULE,
+               .pm     = &ad714x_spi_pm,
+       },
+       .probe          = ad714x_spi_probe,
+       .remove         = ad714x_spi_remove,
+};
+
+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");