1 files changed, 299 insertions, 0 deletions
diff --git a/drivers/hwmon/ams/ams-i2c.c b/drivers/hwmon/ams/ams-i2c.c
new file mode 100644
index 00000000000..0d24bdfea53
--- /dev/null
+++ b/drivers/hwmon/ams/ams-i2c.c
@@ -0,0 +1,299 @@
+/*
+ * 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;
+}