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-rw-r--r--drivers/hwmon/ams/ams-pmu.c207
1 files changed, 207 insertions, 0 deletions
diff --git a/drivers/hwmon/ams/ams-pmu.c b/drivers/hwmon/ams/ams-pmu.c
new file mode 100644
index 000000000000..4636ae031a53
--- /dev/null
+++ b/drivers/hwmon/ams/ams-pmu.c
@@ -0,0 +1,207 @@
+/*
+ * Apple Motion Sensor driver (PMU variant)
+ *
+ * Copyright (C) 2006 Michael Hanselmann (linux-kernel@hansmi.ch)
+ *
+ * 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/adb.h>
+#include <linux/pmu.h>
+
+#include "ams.h"
+
+/* Attitude */
+#define AMS_X 0x00
+#define AMS_Y 0x01
+#define AMS_Z 0x02
+
+/* Not exactly known, maybe chip vendor */
+#define AMS_VENDOR 0x03
+
+/* Freefall registers */
+#define AMS_FF_CLEAR 0x04
+#define AMS_FF_ENABLE 0x05
+#define AMS_FF_LOW_LIMIT 0x06
+#define AMS_FF_DEBOUNCE 0x07
+
+/* Shock registers */
+#define AMS_SHOCK_CLEAR 0x08
+#define AMS_SHOCK_ENABLE 0x09
+#define AMS_SHOCK_HIGH_LIMIT 0x0a
+#define AMS_SHOCK_DEBOUNCE 0x0b
+
+/* Global interrupt and power control register */
+#define AMS_CONTROL 0x0c
+
+static u8 ams_pmu_cmd;
+
+static void ams_pmu_req_complete(struct adb_request *req)
+{
+ complete((struct completion *)req->arg);
+}
+
+/* Only call this function from task context */
+static void ams_pmu_set_register(u8 reg, u8 value)
+{
+ static struct adb_request req;
+ DECLARE_COMPLETION(req_complete);
+
+ req.arg = &req_complete;
+ if (pmu_request(&req, ams_pmu_req_complete, 4, ams_pmu_cmd, 0x00, reg, value))
+ return;
+
+ wait_for_completion(&req_complete);
+}
+
+/* Only call this function from task context */
+static u8 ams_pmu_get_register(u8 reg)
+{
+ static struct adb_request req;
+ DECLARE_COMPLETION(req_complete);
+
+ req.arg = &req_complete;
+ if (pmu_request(&req, ams_pmu_req_complete, 3, ams_pmu_cmd, 0x01, reg))
+ return 0;
+
+ wait_for_completion(&req_complete);
+
+ if (req.reply_len > 0)
+ return req.reply[0];
+ else
+ return 0;
+}
+
+/* Enables or disables the specified interrupts */
+static void ams_pmu_set_irq(enum ams_irq reg, char enable)
+{
+ if (reg & AMS_IRQ_FREEFALL) {
+ u8 val = ams_pmu_get_register(AMS_FF_ENABLE);
+ if (enable)
+ val |= 0x80;
+ else
+ val &= ~0x80;
+ ams_pmu_set_register(AMS_FF_ENABLE, val);
+ }
+
+ if (reg & AMS_IRQ_SHOCK) {
+ u8 val = ams_pmu_get_register(AMS_SHOCK_ENABLE);
+ if (enable)
+ val |= 0x80;
+ else
+ val &= ~0x80;
+ ams_pmu_set_register(AMS_SHOCK_ENABLE, val);
+ }
+
+ if (reg & AMS_IRQ_GLOBAL) {
+ u8 val = ams_pmu_get_register(AMS_CONTROL);
+ if (enable)
+ val |= 0x80;
+ else
+ val &= ~0x80;
+ ams_pmu_set_register(AMS_CONTROL, val);
+ }
+}
+
+static void ams_pmu_clear_irq(enum ams_irq reg)
+{
+ if (reg & AMS_IRQ_FREEFALL)
+ ams_pmu_set_register(AMS_FF_CLEAR, 0x00);
+
+ if (reg & AMS_IRQ_SHOCK)
+ ams_pmu_set_register(AMS_SHOCK_CLEAR, 0x00);
+}
+
+static u8 ams_pmu_get_vendor(void)
+{
+ return ams_pmu_get_register(AMS_VENDOR);
+}
+
+static void ams_pmu_get_xyz(s8 *x, s8 *y, s8 *z)
+{
+ *x = ams_pmu_get_register(AMS_X);
+ *y = ams_pmu_get_register(AMS_Y);
+ *z = ams_pmu_get_register(AMS_Z);
+}
+
+static void ams_pmu_exit(void)
+{
+ /* Disable interrupts */
+ ams_pmu_set_irq(AMS_IRQ_ALL, 0);
+
+ /* Clear interrupts */
+ ams_pmu_clear_irq(AMS_IRQ_ALL);
+
+ ams_info.has_device = 0;
+
+ printk(KERN_INFO "ams: Unloading\n");
+}
+
+int __init ams_pmu_init(struct device_node *np)
+{
+ u32 *prop;
+ int result;
+
+ mutex_lock(&ams_info.lock);
+
+ /* Set implementation stuff */
+ ams_info.of_node = np;
+ ams_info.exit = ams_pmu_exit;
+ ams_info.get_vendor = ams_pmu_get_vendor;
+ ams_info.get_xyz = ams_pmu_get_xyz;
+ ams_info.clear_irq = ams_pmu_clear_irq;
+ ams_info.bustype = BUS_HOST;
+
+ /* Get PMU command, should be 0x4e, but we can never know */
+ prop = (u32*)get_property(ams_info.of_node, "reg", NULL);
+ if (!prop) {
+ result = -ENODEV;
+ goto exit;
+ }
+ ams_pmu_cmd = ((*prop) >> 8) & 0xff;
+
+ /* Disable interrupts */
+ ams_pmu_set_irq(AMS_IRQ_ALL, 0);
+
+ /* Clear interrupts */
+ ams_pmu_clear_irq(AMS_IRQ_ALL);
+
+ result = ams_sensor_attach();
+ if (result < 0)
+ goto exit;
+
+ /* Set default values */
+ ams_pmu_set_register(AMS_FF_LOW_LIMIT, 0x15);
+ ams_pmu_set_register(AMS_FF_ENABLE, 0x08);
+ ams_pmu_set_register(AMS_FF_DEBOUNCE, 0x14);
+
+ ams_pmu_set_register(AMS_SHOCK_HIGH_LIMIT, 0x60);
+ ams_pmu_set_register(AMS_SHOCK_ENABLE, 0x0f);
+ ams_pmu_set_register(AMS_SHOCK_DEBOUNCE, 0x14);
+
+ ams_pmu_set_register(AMS_CONTROL, 0x4f);
+
+ /* Clear interrupts */
+ ams_pmu_clear_irq(AMS_IRQ_ALL);
+
+ ams_info.has_device = 1;
+
+ /* Enable interrupts */
+ ams_pmu_set_irq(AMS_IRQ_ALL, 1);
+
+ printk(KERN_INFO "ams: Found PMU based motion sensor\n");
+
+ result = 0;
+
+exit:
+ mutex_unlock(&ams_info.lock);
+
+ return result;
+}
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