x86, olpc: Add XO-1 SCI driver and power button control

The System Control Interrupt is used in the OLPC XO-1 to control various
features of the laptop. Add the driver base and the power button
functionality.

This driver can't be built as a module, because functionality added in
future patches means that some drivers need to know at boot-time whether
SCI-based functionality is available.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Link: http://lkml.kernel.org/r/1309019658-1712-6-git-send-email-dsd@laptop.org
Acked-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index f473151ac991586e6bb0aadddffe7d0d0d3c90ce..66b7b9d519d53ed7c6eec2843843f43745178f89 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2080,6 +2080,15 @@ config OLPC_XO1_PM
        ---help---
          Add support for poweroff and suspend of the OLPC XO-1 laptop.
 
+config OLPC_XO1_SCI
+       bool "OLPC XO-1 SCI extras"
+       depends on OLPC && OLPC_XO1_PM
+       select GPIO_CS5535
+       select MFD_CORE
+       ---help---
+         Add support for SCI-based features of the OLPC XO-1 laptop:
+          - Power button
+
 endif # X86_32
 
 config AMD_NB

diff --git a/arch/x86/platform/olpc/Makefile b/arch/x86/platform/olpc/Makefile
index 1ae7bed89821985c15183389e7d38a656a301587..1ec5ade97f44e4345f169c9c4c804d7c2da34569 100644 (file)
--- a/arch/x86/platform/olpc/Makefile
+++ b/arch/x86/platform/olpc/Makefile
@@ -1,2 +1,3 @@
 obj-$(CONFIG_OLPC)             += olpc.o olpc_ofw.o olpc_dt.o
 obj-$(CONFIG_OLPC_XO1_PM)              += olpc-xo1-pm.o xo1-wakeup.o
+obj-$(CONFIG_OLPC_XO1_SCI)     += olpc-xo1-sci.o

diff --git a/arch/x86/platform/olpc/olpc-xo1-sci.c b/arch/x86/platform/olpc/olpc-xo1-sci.c
new file mode 100644 (file)
index 0000000..8fbf961
--- /dev/null
+++ b/arch/x86/platform/olpc/olpc-xo1-sci.c
@@ -0,0 +1,191 @@
+/*
+ * 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/input.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/mfd/core.h>
+#include <linux/suspend.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 int sci_irq;
+
+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);
+       }
+
+       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);
+       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_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 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_sci_interrupt(pdev);
+       if (r)
+               free_power_button();
+
+       return r;
+}
+
+static int __devexit xo1_sci_remove(struct platform_device *pdev)
+{
+       mfd_cell_disable(pdev);
+       free_irq(sci_irq, pdev);
+       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,
+};
+
+static int __init xo1_sci_init(void)
+{
+       return platform_driver_register(&xo1_sci_driver);
+}
+arch_initcall(xo1_sci_init);

diff --git a/include/linux/cs5535.h b/include/linux/cs5535.h
index 2facf16f017b50b34cf1d8151d12ad61e776d0e9..6f78235cb9054fe1181e743d82b357ca2908baa9 100644 (file)
--- a/include/linux/cs5535.h
+++ b/include/linux/cs5535.h
@@ -43,6 +43,10 @@
 #define MSR_GX_GLD_MSR_CONFIG  0xC0002001
 #define MSR_GX_MSR_PADSEL      0xC0002011
 
+/* PIC registers */
+#define CS5536_PIC_INT_SEL1    0x4d0
+#define CS5536_PIC_INT_SEL2    0x4d1
+
 /* resource sizes */
 #define LBAR_GPIO_SIZE         0xFF
 #define LBAR_MFGPT_SIZE                0x40
@@ -70,6 +74,10 @@
 #define CS5536_PM1_CNT         0x08
 #define CS5536_PM_GPE0_STS     0x18
 
+/* CS5536_PM1_STS bits */
+#define CS5536_WAK_FLAG                (1 << 15)
+#define CS5536_PWRBTN_FLAG     (1 << 8)
+
 /* CS5536_PM1_EN bits */
 #define CS5536_PM_PWRBTN       (1 << 8)