1 files changed, 277 insertions, 0 deletions

diff --git a/drivers/macintosh/ams/ams-i2c.c b/drivers/macintosh/ams/ams-i2c.c
new file mode 100644
index 000000000000..abeecd27b484
--- /dev/null
+++ b/drivers/macintosh/ams/ams-i2c.c
@@ -0,0 +1,277 @@
+/*
+ * Apple Motion Sensor driver (I2C variant)
+ *
+ * Copyright (C) 2005 Stelian Pop (stelian@popies.net)
+ * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
+ *
+ * Clean room implementation based on the reverse engineered Mac OS X driver by
+ * Johannes Berg <johannes@sipsolutions.net>, documentation available at
+ * http://johannes.sipsolutions.net/PowerBook/Apple_Motion_Sensor_Specification
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+
+#include "ams.h"
+
+/* AMS registers */
+#define AMS_COMMAND     0x00    /* command register */
+#define AMS_STATUS      0x01    /* status register */
+#define AMS_CTRL1       0x02    /* read control 1 (number of values) */
+#define AMS_CTRL2       0x03    /* read control 2 (offset?) */
+#define AMS_CTRL3       0x04    /* read control 3 (size of each value?) */
+#define AMS_DATA1       0x05    /* read data 1 */
+#define AMS_DATA2       0x06    /* read data 2 */
+#define AMS_DATA3       0x07    /* read data 3 */
+#define AMS_DATA4       0x08    /* read data 4 */
+#define AMS_DATAX       0x20    /* data X */
+#define AMS_DATAY       0x21    /* data Y */
+#define AMS_DATAZ       0x22    /* data Z */
+#define AMS_FREEFALL    0x24    /* freefall int control */
+#define AMS_SHOCK       0x25    /* shock int control */
+#define AMS_SENSLOW     0x26    /* sensitivity low limit */
+#define AMS_SENSHIGH    0x27    /* sensitivity high limit */
+#define AMS_CTRLX       0x28    /* control X */
+#define AMS_CTRLY       0x29    /* control Y */
+#define AMS_CTRLZ       0x2A    /* control Z */
+#define AMS_UNKNOWN1    0x2B    /* unknown 1 */
+#define AMS_UNKNOWN2    0x2C    /* unknown 2 */
+#define AMS_UNKNOWN3    0x2D    /* unknown 3 */
+#define AMS_VENDOR      0x2E    /* vendor */
+
+/* AMS commands - use with the AMS_COMMAND register */
+enum ams_i2c_cmd {
+        AMS_CMD_NOOP = 0,
+        AMS_CMD_VERSION,
+        AMS_CMD_READMEM,
+        AMS_CMD_WRITEMEM,
+        AMS_CMD_ERASEMEM,
+        AMS_CMD_READEE,
+        AMS_CMD_WRITEEE,
+        AMS_CMD_RESET,
+        AMS_CMD_START,
+};
+
+static int ams_i2c_probe(struct i2c_client *client,
+                         const struct i2c_device_id *id);
+static int ams_i2c_remove(struct i2c_client *client);
+
+static const struct i2c_device_id ams_id[] = {
+        { "ams", 0 },
+        { }
+};
+MODULE_DEVICE_TABLE(i2c, ams_id);
+
+static struct i2c_driver ams_i2c_driver = {
+        .driver = {
+                .name   = "ams",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = ams_i2c_probe,
+        .remove         = ams_i2c_remove,
+        .id_table       = ams_id,
+};
+
+static s32 ams_i2c_read(u8 reg)
+{
+        return i2c_smbus_read_byte_data(ams_info.i2c_client, reg);
+}
+
+static int ams_i2c_write(u8 reg, u8 value)
+{
+        return i2c_smbus_write_byte_data(ams_info.i2c_client, reg, value);
+}
+
+static int ams_i2c_cmd(enum ams_i2c_cmd cmd)
+{
+        s32 result;
+        int count = 3;
+
+        ams_i2c_write(AMS_COMMAND, cmd);
+        msleep(5);
+
+        while (count--) {
+                result = ams_i2c_read(AMS_COMMAND);
+                if (result == 0 || result & 0x80)
+                        return 0;
+
+                schedule_timeout_uninterruptible(HZ / 20);
+        }
+
+        return -1;
+}
+
+static void ams_i2c_set_irq(enum ams_irq reg, char enable)
+{
+        if (reg & AMS_IRQ_FREEFALL) {
+                u8 val = ams_i2c_read(AMS_CTRLX);
+                if (enable)
+                        val |= 0x80;
+                else
+                        val &= ~0x80;
+                ams_i2c_write(AMS_CTRLX, val);
+        }
+
+        if (reg & AMS_IRQ_SHOCK) {
+                u8 val = ams_i2c_read(AMS_CTRLY);
+                if (enable)
+                        val |= 0x80;
+                else
+                        val &= ~0x80;
+                ams_i2c_write(AMS_CTRLY, val);
+        }
+
+        if (reg & AMS_IRQ_GLOBAL) {
+                u8 val = ams_i2c_read(AMS_CTRLZ);
+                if (enable)
+                        val |= 0x80;
+                else
+                        val &= ~0x80;
+                ams_i2c_write(AMS_CTRLZ, val);
+        }
+}
+
+static void ams_i2c_clear_irq(enum ams_irq reg)
+{
+        if (reg & AMS_IRQ_FREEFALL)
+                ams_i2c_write(AMS_FREEFALL, 0);
+
+        if (reg & AMS_IRQ_SHOCK)
+                ams_i2c_write(AMS_SHOCK, 0);
+}
+
+static u8 ams_i2c_get_vendor(void)
+{
+        return ams_i2c_read(AMS_VENDOR);
+}
+
+static void ams_i2c_get_xyz(s8 *x, s8 *y, s8 *z)
+{
+        *x = ams_i2c_read(AMS_DATAX);
+        *y = ams_i2c_read(AMS_DATAY);
+        *z = ams_i2c_read(AMS_DATAZ);
+}
+
+static int ams_i2c_probe(struct i2c_client *client,
+                         const struct i2c_device_id *id)
+{
+        int vmaj, vmin;
+        int result;
+
+        /* There can be only one */
+        if (unlikely(ams_info.has_device))
+                return -ENODEV;
+
+        ams_info.i2c_client = client;
+
+        if (ams_i2c_cmd(AMS_CMD_RESET)) {
+                printk(KERN_INFO "ams: Failed to reset the device\n");
+                return -ENODEV;
+        }
+
+        if (ams_i2c_cmd(AMS_CMD_START)) {
+                printk(KERN_INFO "ams: Failed to start the device\n");
+                return -ENODEV;
+        }
+
+        /* get version/vendor information */
+        ams_i2c_write(AMS_CTRL1, 0x02);
+        ams_i2c_write(AMS_CTRL2, 0x85);
+        ams_i2c_write(AMS_CTRL3, 0x01);
+
+        ams_i2c_cmd(AMS_CMD_READMEM);
+
+        vmaj = ams_i2c_read(AMS_DATA1);
+        vmin = ams_i2c_read(AMS_DATA2);
+        if (vmaj != 1 || vmin != 52) {
+                printk(KERN_INFO "ams: Incorrect device version (%d.%d)\n",
+                        vmaj, vmin);
+                return -ENODEV;
+        }
+
+        ams_i2c_cmd(AMS_CMD_VERSION);
+
+        vmaj = ams_i2c_read(AMS_DATA1);
+        vmin = ams_i2c_read(AMS_DATA2);
+        if (vmaj != 0 || vmin != 1) {
+                printk(KERN_INFO "ams: Incorrect firmware version (%d.%d)\n",
+                        vmaj, vmin);
+                return -ENODEV;
+        }
+
+        /* Disable interrupts */
+        ams_i2c_set_irq(AMS_IRQ_ALL, 0);
+
+        result = ams_sensor_attach();
+        if (result < 0)
+                return result;
+
+        /* Set default values */
+        ams_i2c_write(AMS_SENSLOW, 0x15);
+        ams_i2c_write(AMS_SENSHIGH, 0x60);
+        ams_i2c_write(AMS_CTRLX, 0x08);
+        ams_i2c_write(AMS_CTRLY, 0x0F);
+        ams_i2c_write(AMS_CTRLZ, 0x4F);
+        ams_i2c_write(AMS_UNKNOWN1, 0x14);
+
+        /* Clear interrupts */
+        ams_i2c_clear_irq(AMS_IRQ_ALL);
+
+        ams_info.has_device = 1;
+
+        /* Enable interrupts */
+        ams_i2c_set_irq(AMS_IRQ_ALL, 1);
+
+        printk(KERN_INFO "ams: Found I2C based motion sensor\n");
+
+        return 0;
+}
+
+static int ams_i2c_remove(struct i2c_client *client)
+{
+        if (ams_info.has_device) {
+                ams_sensor_detach();
+
+                /* Disable interrupts */
+                ams_i2c_set_irq(AMS_IRQ_ALL, 0);
+
+                /* Clear interrupts */
+                ams_i2c_clear_irq(AMS_IRQ_ALL);
+
+                printk(KERN_INFO "ams: Unloading\n");
+
+                ams_info.has_device = 0;
+        }
+
+        return 0;
+}
+
+static void ams_i2c_exit(void)
+{
+        i2c_del_driver(&ams_i2c_driver);
+}
+
+int __init ams_i2c_init(struct device_node *np)
+{
+        int result;
+
+        /* Set implementation stuff */
+        ams_info.of_node = np;
+        ams_info.exit = ams_i2c_exit;
+        ams_info.get_vendor = ams_i2c_get_vendor;
+        ams_info.get_xyz = ams_i2c_get_xyz;
+        ams_info.clear_irq = ams_i2c_clear_irq;
+        ams_info.bustype = BUS_I2C;
+
+        result = i2c_add_driver(&ams_i2c_driver);
+
+        return result;
+}