--- /dev/null
+/*
+ * 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_attach(struct i2c_adapter *adapter);
+static int ams_i2c_detach(struct i2c_adapter *adapter);
+
+static struct i2c_driver ams_i2c_driver = {
+ .driver = {
+ .name = "ams",
+ .owner = THIS_MODULE,
+ },
+ .attach_adapter = ams_i2c_attach,
+ .detach_adapter = ams_i2c_detach,
+};
+
+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 remaining = HZ / 20;
+
+ ams_i2c_write(AMS_COMMAND, cmd);
+ mdelay(5);
+
+ while (remaining) {
+ result = ams_i2c_read(AMS_COMMAND);
+ if (result == 0 || result & 0x80)
+ return 0;
+
+ remaining = schedule_timeout(remaining);
+ }
+
+ 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_attach(struct i2c_adapter *adapter)
+{
+ unsigned long bus;
+ int vmaj, vmin;
+ int result;
+
+ /* There can be only one */
+ if (unlikely(ams_info.has_device))
+ return -ENODEV;
+
+ if (strncmp(adapter->name, "uni-n", 5))
+ return -ENODEV;
+
+ bus = simple_strtoul(adapter->name + 6, NULL, 10);
+ if (bus != ams_info.i2c_bus)
+ return -ENODEV;
+
+ ams_info.i2c_client.addr = ams_info.i2c_address;
+ ams_info.i2c_client.adapter = adapter;
+ ams_info.i2c_client.driver = &ams_i2c_driver;
+ strcpy(ams_info.i2c_client.name, "Apple Motion Sensor");
+
+ 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_detach(struct i2c_adapter *adapter)
+{
+ if (ams_info.has_device) {
+ /* 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)
+{
+ char *tmp_bus;
+ int result;
+ u32 *prop;
+
+ mutex_lock(&ams_info.lock);
+
+ /* 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;
+
+ /* look for bus either using "reg" or by path */
+ prop = (u32*)get_property(ams_info.of_node, "reg", NULL);
+ if (!prop) {
+ result = -ENODEV;
+
+ goto exit;
+ }
+
+ tmp_bus = strstr(ams_info.of_node->full_name, "/i2c-bus@");
+ if (tmp_bus)
+ ams_info.i2c_bus = *(tmp_bus + 9) - '0';
+ else
+ ams_info.i2c_bus = ((*prop) >> 8) & 0x0f;
+ ams_info.i2c_address = ((*prop) & 0xff) >> 1;
+
+ result = i2c_add_driver(&ams_i2c_driver);
+
+exit:
+ mutex_unlock(&ams_info.lock);
+
+ return result;
+}
git://git.onelab.eu / linux-2.6.git / blobdiff