diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/platform/olpc/olpc-xo1-sci.c | 642 |
1 files changed, 642 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 000000000..7fa8b3b53 --- /dev/null +++ b/arch/x86/platform/olpc/olpc-xo1-sci.c @@ -0,0 +1,642 @@ +/* + * 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/pm_wakeup.h> +#include <linux/mfd/core.h> +#include <linux/power_supply.h> +#include <linux/suspend.h> +#include <linux/workqueue.h> +#include <linux/olpc-ec.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); + power_supply_put(psy); + } +} + +static void ac_status_changed(void) +{ + struct power_supply *psy = power_supply_get_by_name("olpc-ac"); + + if (psy) { + power_supply_changed(psy); + power_supply_put(psy); + } +} + +/* 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; + } + + if (!!test_bit(SW_TABLET_MODE, ebook_switch_idev->sw) == state) + return; /* Nothing new to report. */ + + input_report_switch(ebook_switch_idev, SW_TABLET_MODE, state); + input_sync(ebook_switch_idev); + pm_wakeup_event(&ebook_switch_idev->dev, 0); +} + +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) +{ + if (!!test_bit(SW_LID, lid_switch_idev->sw) == !lid_open) + return; /* Nothing new to report. */ + + input_report_switch(lid_switch_idev, SW_LID, !lid_open); + input_sync(lid_switch_idev); + pm_wakeup_event(&lid_switch_idev->dev, 0); +} + +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) { + if (!(sts & CS5536_WAK_FLAG)) { + /* Only report power button input when it was pressed + * during regular operation (as opposed to when it + * was used to wake the system). */ + 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); + } + /* Report the wakeup event in all cases. */ + pm_wakeup_event(&power_button_idev->dev, 0); + } + + if ((sts & (CS5536_RTC_FLAG | CS5536_WAK_FLAG)) == + (CS5536_RTC_FLAG | CS5536_WAK_FLAG)) { + /* When the system is woken by the RTC alarm, report the + * event on the rtc device. */ + struct device *rtc = bus_find_device_by_name( + &platform_bus_type, NULL, "rtc_cmos"); + if (rtc) { + pm_wakeup_event(rtc, 0); + put_device(rtc); + } + } + + 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 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 interesting SCI events, and clear pending interrupts */ + sts = inl(acpi_base + CS5536_PM1_STS); + outl(((CS5536_PM_PWRBTN | CS5536_PM_RTC) << 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 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 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 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); +} + +static int 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); +} + +static int 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); + lid_switch_idev = NULL; +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); +} + +static int 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 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 = 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); |