Input: add driver for ADXL345/346 Digital Accelerometers

This is a driver for the ADXL345/346 Three-Axis Digital Accelerometers.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Chris Verges <chrisv@cyberswitching.com>
Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 145 insertions, 0 deletions

diff --git a/drivers/input/misc/adxl34x-spi.c b/drivers/input/misc/adxl34x-spi.c
new file mode 100644
index 000000000000..7f992353ffdd
--- /dev/null
+++ b/drivers/input/misc/adxl34x-spi.c
@@ -0,0 +1,145 @@
+/*
+ * ADLX345/346 Three-Axis Digital Accelerometers (SPI Interface)
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Copyright (C) 2009 Michael Hennerich, 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/types.h>
+#include "adxl34x.h"
+
+#define MAX_SPI_FREQ_HZ         5000000
+#define MAX_FREQ_NO_FIFODELAY   1500000
+#define ADXL34X_CMD_MULTB       (1 << 6)
+#define ADXL34X_CMD_READ        (1 << 7)
+#define ADXL34X_WRITECMD(reg)   (reg & 0x3F)
+#define ADXL34X_READCMD(reg)    (ADXL34X_CMD_READ | (reg & 0x3F))
+#define ADXL34X_READMB_CMD(reg) (ADXL34X_CMD_READ | ADXL34X_CMD_MULTB \
+                                        | (reg & 0x3F))
+
+static int adxl34x_spi_read(struct device *dev, unsigned char reg)
+{
+        struct spi_device *spi = to_spi_device(dev);
+        unsigned char cmd;
+
+        cmd = ADXL34X_READCMD(reg);
+
+        return spi_w8r8(spi, cmd);
+}
+
+static int adxl34x_spi_write(struct device *dev,
+                             unsigned char reg, unsigned char val)
+{
+        struct spi_device *spi = to_spi_device(dev);
+        unsigned char buf[2];
+
+        buf[0] = ADXL34X_WRITECMD(reg);
+        buf[1] = val;
+
+        return spi_write(spi, buf, sizeof(buf));
+}
+
+static int adxl34x_spi_read_block(struct device *dev,
+                                  unsigned char reg, int count,
+                                  void *buf)
+{
+        struct spi_device *spi = to_spi_device(dev);
+        ssize_t status;
+
+        reg = ADXL34X_READMB_CMD(reg);
+        status = spi_write_then_read(spi, &reg, 1, buf, count);
+
+        return (status < 0) ? status : 0;
+}
+
+static const struct adxl34x_bus_ops adx134x_spi_bops = {
+        .bustype        = BUS_SPI,
+        .write          = adxl34x_spi_write,
+        .read           = adxl34x_spi_read,
+        .read_block     = adxl34x_spi_read_block,
+};
+
+static int __devinit adxl34x_spi_probe(struct spi_device *spi)
+{
+        struct adxl34x *ac;
+
+        /* don't exceed max specified SPI CLK frequency */
+        if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) {
+                dev_err(&spi->dev, "SPI CLK %d Hz too fast\n", spi->max_speed_hz);
+                return -EINVAL;
+        }
+
+        ac = adxl34x_probe(&spi->dev, spi->irq,
+                           spi->max_speed_hz > MAX_FREQ_NO_FIFODELAY,
+                           &adx134x_spi_bops);
+
+        if (IS_ERR(ac))
+                return PTR_ERR(ac);
+
+        spi_set_drvdata(spi, ac);
+
+        return 0;
+}
+
+static int __devexit adxl34x_spi_remove(struct spi_device *spi)
+{
+        struct adxl34x *ac = dev_get_drvdata(&spi->dev);
+
+        return adxl34x_remove(ac);
+}
+
+#ifdef CONFIG_PM
+static int adxl34x_suspend(struct spi_device *spi, pm_message_t message)
+{
+        struct adxl34x *ac = dev_get_drvdata(&spi->dev);
+
+        adxl34x_disable(ac);
+
+        return 0;
+}
+
+static int adxl34x_resume(struct spi_device *spi)
+{
+        struct adxl34x *ac = dev_get_drvdata(&spi->dev);
+
+        adxl34x_enable(ac);
+
+        return 0;
+}
+#else
+# define adxl34x_suspend NULL
+# define adxl34x_resume  NULL
+#endif
+
+static struct spi_driver adxl34x_driver = {
+        .driver = {
+                .name = "adxl34x",
+                .bus = &spi_bus_type,
+                .owner = THIS_MODULE,
+        },
+        .probe   = adxl34x_spi_probe,
+        .remove  = __devexit_p(adxl34x_spi_remove),
+        .suspend = adxl34x_suspend,
+        .resume  = adxl34x_resume,
+};
+
+static int __init adxl34x_spi_init(void)
+{
+        return spi_register_driver(&adxl34x_driver);
+}
+module_init(adxl34x_spi_init);
+
+static void __exit adxl34x_spi_exit(void)
+{
+        spi_unregister_driver(&adxl34x_driver);
+}
+module_exit(adxl34x_spi_exit);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("ADXL345/346 Three-Axis Digital Accelerometer SPI Bus Driver");
+MODULE_LICENSE("GPL");