1 files changed, 614 insertions, 0 deletions

diff --git a/arch/x86/platform/olpc/olpc-xo1-sci.c b/arch/x86/platform/olpc/olpc-xo1-sci.c
new file mode 100644
index 000000000000..1d4c783d7325
--- /dev/null
+++ b/arch/x86/platform/olpc/olpc-xo1-sci.c
@@ -0,0 +1,614 @@
+/*
+ * Support for OLPC XO-1 System Control Interrupts (SCI)
+ *
+ * Copyright (C) 2010 One Laptop per Child
+ * Copyright (C) 2006 Red Hat, Inc.
+ * Copyright (C) 2006 Advanced Micro Devices, Inc.
+ *
+ * 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/cs5535.h>
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/mfd/core.h>
+#include <linux/power_supply.h>
+#include <linux/suspend.h>
+#include <linux/workqueue.h>
+
+#include <asm/io.h>
+#include <asm/msr.h>
+#include <asm/olpc.h>
+
+#define DRV_NAME        "olpc-xo1-sci"
+#define PFX             DRV_NAME ": "
+
+static unsigned long acpi_base;
+static struct input_dev *power_button_idev;
+static struct input_dev *ebook_switch_idev;
+static struct input_dev *lid_switch_idev;
+
+static int sci_irq;
+
+static bool lid_open;
+static bool lid_inverted;
+static int lid_wake_mode;
+
+enum lid_wake_modes {
+        LID_WAKE_ALWAYS,
+        LID_WAKE_OPEN,
+        LID_WAKE_CLOSE,
+};
+
+static const char * const lid_wake_mode_names[] = {
+        [LID_WAKE_ALWAYS] = "always",
+        [LID_WAKE_OPEN] = "open",
+        [LID_WAKE_CLOSE] = "close",
+};
+
+static void battery_status_changed(void)
+{
+        struct power_supply *psy = power_supply_get_by_name("olpc-battery");
+
+        if (psy) {
+                power_supply_changed(psy);
+                put_device(psy->dev);
+        }
+}
+
+static void ac_status_changed(void)
+{
+        struct power_supply *psy = power_supply_get_by_name("olpc-ac");
+
+        if (psy) {
+                power_supply_changed(psy);
+                put_device(psy->dev);
+        }
+}
+
+/* Report current ebook switch state through input layer */
+static void send_ebook_state(void)
+{
+        unsigned char state;
+
+        if (olpc_ec_cmd(EC_READ_EB_MODE, NULL, 0, &state, 1)) {
+                pr_err(PFX "failed to get ebook state\n");
+                return;
+        }
+
+        input_report_switch(ebook_switch_idev, SW_TABLET_MODE, state);
+        input_sync(ebook_switch_idev);
+}
+
+static void flip_lid_inverter(void)
+{
+        /* gpio is high; invert so we'll get l->h event interrupt */
+        if (lid_inverted)
+                cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_INPUT_INVERT);
+        else
+                cs5535_gpio_set(OLPC_GPIO_LID, GPIO_INPUT_INVERT);
+        lid_inverted = !lid_inverted;
+}
+
+static void detect_lid_state(void)
+{
+        /*
+         * the edge detector hookup on the gpio inputs on the geode is
+         * odd, to say the least.  See http://dev.laptop.org/ticket/5703
+         * for details, but in a nutshell:  we don't use the edge
+         * detectors.  instead, we make use of an anomoly:  with the both
+         * edge detectors turned off, we still get an edge event on a
+         * positive edge transition.  to take advantage of this, we use the
+         * front-end inverter to ensure that that's the edge we're always
+         * going to see next.
+         */
+
+        int state;
+
+        state = cs5535_gpio_isset(OLPC_GPIO_LID, GPIO_READ_BACK);
+        lid_open = !state ^ !lid_inverted; /* x ^^ y */
+        if (!state)
+                return;
+
+        flip_lid_inverter();
+}
+
+/* Report current lid switch state through input layer */
+static void send_lid_state(void)
+{
+        input_report_switch(lid_switch_idev, SW_LID, !lid_open);
+        input_sync(lid_switch_idev);
+}
+
+static ssize_t lid_wake_mode_show(struct device *dev,
+                                  struct device_attribute *attr, char *buf)
+{
+        const char *mode = lid_wake_mode_names[lid_wake_mode];
+        return sprintf(buf, "%s\n", mode);
+}
+static ssize_t lid_wake_mode_set(struct device *dev,
+                                 struct device_attribute *attr,
+                                 const char *buf, size_t count)
+{
+        int i;
+        for (i = 0; i < ARRAY_SIZE(lid_wake_mode_names); i++) {
+                const char *mode = lid_wake_mode_names[i];
+                if (strlen(mode) != count || strncasecmp(mode, buf, count))
+                        continue;
+
+                lid_wake_mode = i;
+                return count;
+        }
+        return -EINVAL;
+}
+static DEVICE_ATTR(lid_wake_mode, S_IWUSR | S_IRUGO, lid_wake_mode_show,
+                   lid_wake_mode_set);
+
+/*
+ * Process all items in the EC's SCI queue.
+ *
+ * This is handled in a workqueue because olpc_ec_cmd can be slow (and
+ * can even timeout).
+ *
+ * If propagate_events is false, the queue is drained without events being
+ * generated for the interrupts.
+ */
+static void process_sci_queue(bool propagate_events)
+{
+        int r;
+        u16 data;
+
+        do {
+                r = olpc_ec_sci_query(&data);
+                if (r || !data)
+                        break;
+
+                pr_debug(PFX "SCI 0x%x received\n", data);
+
+                switch (data) {
+                case EC_SCI_SRC_BATERR:
+                case EC_SCI_SRC_BATSOC:
+                case EC_SCI_SRC_BATTERY:
+                case EC_SCI_SRC_BATCRIT:
+                        battery_status_changed();
+                        break;
+                case EC_SCI_SRC_ACPWR:
+                        ac_status_changed();
+                        break;
+                }
+
+                if (data == EC_SCI_SRC_EBOOK && propagate_events)
+                        send_ebook_state();
+        } while (data);
+
+        if (r)
+                pr_err(PFX "Failed to clear SCI queue");
+}
+
+static void process_sci_queue_work(struct work_struct *work)
+{
+        process_sci_queue(true);
+}
+
+static DECLARE_WORK(sci_work, process_sci_queue_work);
+
+static irqreturn_t xo1_sci_intr(int irq, void *dev_id)
+{
+        struct platform_device *pdev = dev_id;
+        u32 sts;
+        u32 gpe;
+
+        sts = inl(acpi_base + CS5536_PM1_STS);
+        outl(sts | 0xffff, acpi_base + CS5536_PM1_STS);
+
+        gpe = inl(acpi_base + CS5536_PM_GPE0_STS);
+        outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS);
+
+        dev_dbg(&pdev->dev, "sts %x gpe %x\n", sts, gpe);
+
+        if (sts & CS5536_PWRBTN_FLAG && !(sts & CS5536_WAK_FLAG)) {
+                input_report_key(power_button_idev, KEY_POWER, 1);
+                input_sync(power_button_idev);
+                input_report_key(power_button_idev, KEY_POWER, 0);
+                input_sync(power_button_idev);
+        }
+
+        if (gpe & CS5536_GPIOM7_PME_FLAG) { /* EC GPIO */
+                cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS);
+                schedule_work(&sci_work);
+        }
+
+        cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS);
+        cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS);
+        detect_lid_state();
+        send_lid_state();
+
+        return IRQ_HANDLED;
+}
+
+static int xo1_sci_suspend(struct platform_device *pdev, pm_message_t state)
+{
+        if (device_may_wakeup(&power_button_idev->dev))
+                olpc_xo1_pm_wakeup_set(CS5536_PM_PWRBTN);
+        else
+                olpc_xo1_pm_wakeup_clear(CS5536_PM_PWRBTN);
+
+        if (device_may_wakeup(&ebook_switch_idev->dev))
+                olpc_ec_wakeup_set(EC_SCI_SRC_EBOOK);
+        else
+                olpc_ec_wakeup_clear(EC_SCI_SRC_EBOOK);
+
+        if (!device_may_wakeup(&lid_switch_idev->dev)) {
+                cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+        } else if ((lid_open && lid_wake_mode == LID_WAKE_OPEN) ||
+                   (!lid_open && lid_wake_mode == LID_WAKE_CLOSE)) {
+                flip_lid_inverter();
+
+                /* we may have just caused an event */
+                cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS);
+                cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS);
+
+                cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+        }
+
+        return 0;
+}
+
+static int xo1_sci_resume(struct platform_device *pdev)
+{
+        /*
+         * We don't know what may have happened while we were asleep.
+         * Reestablish our lid setup so we're sure to catch all transitions.
+         */
+        detect_lid_state();
+        send_lid_state();
+        cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+
+        /* Enable all EC events */
+        olpc_ec_mask_write(EC_SCI_SRC_ALL);
+
+        /* Power/battery status might have changed too */
+        battery_status_changed();
+        ac_status_changed();
+        return 0;
+}
+
+static int __devinit setup_sci_interrupt(struct platform_device *pdev)
+{
+        u32 lo, hi;
+        u32 sts;
+        int r;
+
+        rdmsr(0x51400020, lo, hi);
+        sci_irq = (lo >> 20) & 15;
+
+        if (sci_irq) {
+                dev_info(&pdev->dev, "SCI is mapped to IRQ %d\n", sci_irq);
+        } else {
+                /* Zero means masked */
+                dev_info(&pdev->dev, "SCI unmapped. Mapping to IRQ 3\n");
+                sci_irq = 3;
+                lo |= 0x00300000;
+                wrmsrl(0x51400020, lo);
+        }
+
+        /* Select level triggered in PIC */
+        if (sci_irq < 8) {
+                lo = inb(CS5536_PIC_INT_SEL1);
+                lo |= 1 << sci_irq;
+                outb(lo, CS5536_PIC_INT_SEL1);
+        } else {
+                lo = inb(CS5536_PIC_INT_SEL2);
+                lo |= 1 << (sci_irq - 8);
+                outb(lo, CS5536_PIC_INT_SEL2);
+        }
+
+        /* Enable SCI from power button, and clear pending interrupts */
+        sts = inl(acpi_base + CS5536_PM1_STS);
+        outl((CS5536_PM_PWRBTN << 16) | 0xffff, acpi_base + CS5536_PM1_STS);
+
+        r = request_irq(sci_irq, xo1_sci_intr, 0, DRV_NAME, pdev);
+        if (r)
+                dev_err(&pdev->dev, "can't request interrupt\n");
+
+        return r;
+}
+
+static int __devinit setup_ec_sci(void)
+{
+        int r;
+
+        r = gpio_request(OLPC_GPIO_ECSCI, "OLPC-ECSCI");
+        if (r)
+                return r;
+
+        gpio_direction_input(OLPC_GPIO_ECSCI);
+
+        /* Clear pending EC SCI events */
+        cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS);
+        cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_POSITIVE_EDGE_STS);
+
+        /*
+         * Enable EC SCI events, and map them to both a PME and the SCI
+         * interrupt.
+         *
+         * Ordinarily, in addition to functioning as GPIOs, Geode GPIOs can
+         * be mapped to regular interrupts *or* Geode-specific Power
+         * Management Events (PMEs) - events that bring the system out of
+         * suspend. In this case, we want both of those things - the system
+         * wakeup, *and* the ability to get an interrupt when an event occurs.
+         *
+         * To achieve this, we map the GPIO to a PME, and then we use one
+         * of the many generic knobs on the CS5535 PIC to additionally map the
+         * PME to the regular SCI interrupt line.
+         */
+        cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_EVENTS_ENABLE);
+
+        /* Set the SCI to cause a PME event on group 7 */
+        cs5535_gpio_setup_event(OLPC_GPIO_ECSCI, 7, 1);
+
+        /* And have group 7 also fire the SCI interrupt */
+        cs5535_pic_unreqz_select_high(7, sci_irq);
+
+        return 0;
+}
+
+static void free_ec_sci(void)
+{
+        gpio_free(OLPC_GPIO_ECSCI);
+}
+
+static int __devinit setup_lid_events(void)
+{
+        int r;
+
+        r = gpio_request(OLPC_GPIO_LID, "OLPC-LID");
+        if (r)
+                return r;
+
+        gpio_direction_input(OLPC_GPIO_LID);
+
+        cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_INPUT_INVERT);
+        lid_inverted = 0;
+
+        /* Clear edge detection and event enable for now */
+        cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+        cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_EN);
+        cs5535_gpio_clear(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_EN);
+        cs5535_gpio_set(OLPC_GPIO_LID, GPIO_NEGATIVE_EDGE_STS);
+        cs5535_gpio_set(OLPC_GPIO_LID, GPIO_POSITIVE_EDGE_STS);
+
+        /* Set the LID to cause an PME event on group 6 */
+        cs5535_gpio_setup_event(OLPC_GPIO_LID, 6, 1);
+
+        /* Set PME group 6 to fire the SCI interrupt */
+        cs5535_gpio_set_irq(6, sci_irq);
+
+        /* Enable the event */
+        cs5535_gpio_set(OLPC_GPIO_LID, GPIO_EVENTS_ENABLE);
+
+        return 0;
+}
+
+static void free_lid_events(void)
+{
+        gpio_free(OLPC_GPIO_LID);
+}
+
+static int __devinit setup_power_button(struct platform_device *pdev)
+{
+        int r;
+
+        power_button_idev = input_allocate_device();
+        if (!power_button_idev)
+                return -ENOMEM;
+
+        power_button_idev->name = "Power Button";
+        power_button_idev->phys = DRV_NAME "/input0";
+        set_bit(EV_KEY, power_button_idev->evbit);
+        set_bit(KEY_POWER, power_button_idev->keybit);
+
+        power_button_idev->dev.parent = &pdev->dev;
+        device_init_wakeup(&power_button_idev->dev, 1);
+
+        r = input_register_device(power_button_idev);
+        if (r) {
+                dev_err(&pdev->dev, "failed to register power button: %d\n", r);
+                input_free_device(power_button_idev);
+        }
+
+        return r;
+}
+
+static void free_power_button(void)
+{
+        input_unregister_device(power_button_idev);
+        input_free_device(power_button_idev);
+}
+
+static int __devinit setup_ebook_switch(struct platform_device *pdev)
+{
+        int r;
+
+        ebook_switch_idev = input_allocate_device();
+        if (!ebook_switch_idev)
+                return -ENOMEM;
+
+        ebook_switch_idev->name = "EBook Switch";
+        ebook_switch_idev->phys = DRV_NAME "/input1";
+        set_bit(EV_SW, ebook_switch_idev->evbit);
+        set_bit(SW_TABLET_MODE, ebook_switch_idev->swbit);
+
+        ebook_switch_idev->dev.parent = &pdev->dev;
+        device_set_wakeup_capable(&ebook_switch_idev->dev, true);
+
+        r = input_register_device(ebook_switch_idev);
+        if (r) {
+                dev_err(&pdev->dev, "failed to register ebook switch: %d\n", r);
+                input_free_device(ebook_switch_idev);
+        }
+
+        return r;
+}
+
+static void free_ebook_switch(void)
+{
+        input_unregister_device(ebook_switch_idev);
+        input_free_device(ebook_switch_idev);
+}
+
+static int __devinit setup_lid_switch(struct platform_device *pdev)
+{
+        int r;
+
+        lid_switch_idev = input_allocate_device();
+        if (!lid_switch_idev)
+                return -ENOMEM;
+
+        lid_switch_idev->name = "Lid Switch";
+        lid_switch_idev->phys = DRV_NAME "/input2";
+        set_bit(EV_SW, lid_switch_idev->evbit);
+        set_bit(SW_LID, lid_switch_idev->swbit);
+
+        lid_switch_idev->dev.parent = &pdev->dev;
+        device_set_wakeup_capable(&lid_switch_idev->dev, true);
+
+        r = input_register_device(lid_switch_idev);
+        if (r) {
+                dev_err(&pdev->dev, "failed to register lid switch: %d\n", r);
+                goto err_register;
+        }
+
+        r = device_create_file(&lid_switch_idev->dev, &dev_attr_lid_wake_mode);
+        if (r) {
+                dev_err(&pdev->dev, "failed to create wake mode attr: %d\n", r);
+                goto err_create_attr;
+        }
+
+        return 0;
+
+err_create_attr:
+        input_unregister_device(lid_switch_idev);
+err_register:
+        input_free_device(lid_switch_idev);
+        return r;
+}
+
+static void free_lid_switch(void)
+{
+        device_remove_file(&lid_switch_idev->dev, &dev_attr_lid_wake_mode);
+        input_unregister_device(lid_switch_idev);
+        input_free_device(lid_switch_idev);
+}
+
+static int __devinit xo1_sci_probe(struct platform_device *pdev)
+{
+        struct resource *res;
+        int r;
+
+        /* don't run on non-XOs */
+        if (!machine_is_olpc())
+                return -ENODEV;
+
+        r = mfd_cell_enable(pdev);
+        if (r)
+                return r;
+
+        res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+        if (!res) {
+                dev_err(&pdev->dev, "can't fetch device resource info\n");
+                return -EIO;
+        }
+        acpi_base = res->start;
+
+        r = setup_power_button(pdev);
+        if (r)
+                return r;
+
+        r = setup_ebook_switch(pdev);
+        if (r)
+                goto err_ebook;
+
+        r = setup_lid_switch(pdev);
+        if (r)
+                goto err_lid;
+
+        r = setup_lid_events();
+        if (r)
+                goto err_lidevt;
+
+        r = setup_ec_sci();
+        if (r)
+                goto err_ecsci;
+
+        /* Enable PME generation for EC-generated events */
+        outl(CS5536_GPIOM6_PME_EN | CS5536_GPIOM7_PME_EN,
+                acpi_base + CS5536_PM_GPE0_EN);
+
+        /* Clear pending events */
+        outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS);
+        process_sci_queue(false);
+
+        /* Initial sync */
+        send_ebook_state();
+        detect_lid_state();
+        send_lid_state();
+
+        r = setup_sci_interrupt(pdev);
+        if (r)
+                goto err_sci;
+
+        /* Enable all EC events */
+        olpc_ec_mask_write(EC_SCI_SRC_ALL);
+
+        return r;
+
+err_sci:
+        free_ec_sci();
+err_ecsci:
+        free_lid_events();
+err_lidevt:
+        free_lid_switch();
+err_lid:
+        free_ebook_switch();
+err_ebook:
+        free_power_button();
+        return r;
+}
+
+static int __devexit xo1_sci_remove(struct platform_device *pdev)
+{
+        mfd_cell_disable(pdev);
+        free_irq(sci_irq, pdev);
+        cancel_work_sync(&sci_work);
+        free_ec_sci();
+        free_lid_events();
+        free_lid_switch();
+        free_ebook_switch();
+        free_power_button();
+        acpi_base = 0;
+        return 0;
+}
+
+static struct platform_driver xo1_sci_driver = {
+        .driver = {
+                .name = "olpc-xo1-sci-acpi",
+        },
+        .probe = xo1_sci_probe,
+        .remove = __devexit_p(xo1_sci_remove),
+        .suspend = xo1_sci_suspend,
+        .resume = xo1_sci_resume,
+};
+
+static int __init xo1_sci_init(void)
+{
+        return platform_driver_register(&xo1_sci_driver);
+}
+arch_initcall(xo1_sci_init);