lis3: SPI transport layer

Make use of the new abstraction layer and add a new transport layer for
spi.  Works fine on a PXA based board.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Eric Piel <eric.piel@tremplin-utc.net>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 131 insertions, 0 deletions

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index bc6810c22dd7..ce52bf2f235e 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -932,6 +932,22 @@ config SENSORS_LIS3LV02D
           Say Y here if you have an applicable laptop and want to experience
           the awesome power of lis3lv02d.
 
+config SENSORS_LIS3_SPI
+        tristate "STMicroeletronics LIS3LV02Dx three-axis digital accelerometer (SPI)"
+        depends on !ACPI && SPI_MASTER && INPUT
+        default n
+        help
+          This driver provides support for the LIS3LV02Dx accelerometer connected
+          via SPI. The accelerometer data is readable via
+          /sys/devices/platform/lis3lv02d.
+
+          This driver also provides an absolute input class device, allowing
+          the laptop to act as a pinball machine-esque joystick.
+
+          This driver can also be built as modules.  If so, the core module
+          will be called lis3lv02d and a specific module for the SPI transport
+          is called lis3lv02d_spi.
+
 config SENSORS_APPLESMC
         tristate "Apple SMC (Motion sensor, light sensor, keyboard backlight)"
         depends on INPUT && X86
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 4da261d16abf..3a6b1f06f8f4 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_SENSORS_IBMPEX)	+= ibmpex.o
 obj-$(CONFIG_SENSORS_IT87)      += it87.o
 obj-$(CONFIG_SENSORS_K8TEMP)    += k8temp.o
 obj-$(CONFIG_SENSORS_LIS3LV02D) += lis3lv02d.o hp_accel.o
+obj-$(CONFIG_SENSORS_LIS3_SPI)  += lis3lv02d.o lis3lv02d_spi.o
 obj-$(CONFIG_SENSORS_LM63)      += lm63.o
 obj-$(CONFIG_SENSORS_LM70)      += lm70.o
 obj-$(CONFIG_SENSORS_LM75)      += lm75.o
diff --git a/drivers/hwmon/lis3lv02d_spi.c b/drivers/hwmon/lis3lv02d_spi.c
new file mode 100644
index 000000000000..07ae74b0e191
--- /dev/null
+++ b/drivers/hwmon/lis3lv02d_spi.c
@@ -0,0 +1,114 @@
+/*
+ * lis3lv02d_spi - SPI glue layer for lis3lv02d
+ *
+ * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  publishhed by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/spi/spi.h>
+
+#include "lis3lv02d.h"
+
+#define DRV_NAME        "lis3lv02d_spi"
+#define LIS3_SPI_READ   0x80
+
+static int lis3_spi_read(struct lis3lv02d *lis3, int reg, u8 *v)
+{
+        struct spi_device *spi = lis3->bus_priv;
+        int ret = spi_w8r8(spi, reg | LIS3_SPI_READ);
+        if (ret < 0)
+                return -EINVAL;
+
+        *v = (u8) ret;
+        return 0;
+}
+
+static int lis3_spi_write(struct lis3lv02d *lis3, int reg, u8 val)
+{
+        u8 tmp[2] = { reg, val };
+        struct spi_device *spi = lis3->bus_priv;
+        return spi_write(spi, tmp, sizeof(tmp));
+}
+
+static int lis3_spi_init(struct lis3lv02d *lis3)
+{
+        u8 reg;
+        int ret;
+
+        /* power up the device */
+        ret = lis3->read(lis3, CTRL_REG1, &reg);
+        if (ret < 0)
+                return ret;
+
+        reg |= CTRL1_PD0;
+        return lis3->write(lis3, CTRL_REG1, reg);
+}
+
+static struct axis_conversion lis3lv02d_axis_normal = { 1, 2, 3 };
+
+static int __devinit lis302dl_spi_probe(struct spi_device *spi)
+{
+        int ret;
+
+        spi->bits_per_word = 8;
+        spi->mode = SPI_MODE_0;
+        ret = spi_setup(spi);
+        if (ret < 0)
+                return ret;
+
+        lis3_dev.bus_priv = spi;
+        lis3_dev.init = lis3_spi_init;
+        lis3_dev.read = lis3_spi_read;
+        lis3_dev.write = lis3_spi_write;
+        lis3_dev.irq = spi->irq;
+        lis3_dev.ac = lis3lv02d_axis_normal;
+        spi_set_drvdata(spi, &lis3_dev);
+
+        ret = lis3lv02d_init_device(&lis3_dev);
+        return ret;
+}
+
+static int __devexit lis302dl_spi_remove(struct spi_device *spi)
+{
+        struct lis3lv02d *lis3 = spi_get_drvdata(spi);
+        lis3lv02d_joystick_disable();
+        lis3lv02d_poweroff(lis3);
+        return 0;
+}
+
+static struct spi_driver lis302dl_spi_driver = {
+        .driver  = {
+                .name   = DRV_NAME,
+                .owner  = THIS_MODULE,
+        },
+        .probe  = lis302dl_spi_probe,
+        .remove = __devexit_p(lis302dl_spi_remove),
+};
+
+static int __init lis302dl_init(void)
+{
+        return spi_register_driver(&lis302dl_spi_driver);
+}
+
+static void __exit lis302dl_exit(void)
+{
+        spi_unregister_driver(&lis302dl_spi_driver);
+}
+
+module_init(lis302dl_init);
+module_exit(lis302dl_exit);
+
+MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
+MODULE_DESCRIPTION("lis3lv02d SPI glue layer");
+MODULE_LICENSE("GPL");
+