gemini pwc

drivers/misc/Kconfig

@@ -95,6 +95,17 @@ config ATMEL_TCB_CLKSRC_BLOCK
 	  TC can be used for other purposes, such as PWM generation and
 	  interval timing.
 
+config GEMINI_POWER_CTRL
+	tristate "Gemini Power Control"
+	depends on ARCH_GEMINI
+	help
+	  Say Y here if you want to build a driver for the Gemini Power Control
+	  device. You propably want this, as it's needed to switch off devices
+	  based on the Gemini Platform with the powerbutton.
+
+	  If you choose to build this as module, it's name will be gemini_pwc.
+	  If unsure, say Y here.
+
 config IBM_ASM
 	tristate "Device driver for IBM RSA service processor"
 	depends on X86 && PCI && INPUT && EXPERIMENTAL

drivers/misc/Makefile

@@ -10,6 +10,7 @@ obj-$(CONFIG_ATMEL_PWM)		+= atmel_pwm.o
 obj-$(CONFIG_ATMEL_SSC)		+= atmel-ssc.o
 obj-$(CONFIG_ATMEL_TCLIB)	+= atmel_tclib.o
 obj-$(CONFIG_BMP085)		+= bmp085.o
+obj-$(CONFIG_GEMINI_POWER_CTRL)	+= gemini_pwc.o
 obj-$(CONFIG_ICS932S401)	+= ics932s401.o
 obj-$(CONFIG_LKDTM)		+= lkdtm.o
 obj-$(CONFIG_TIFM_CORE)       	+= tifm_core.o

drivers/misc/gemini_pwc.c

@@ -0,0 +1,195 @@
+/*
+ *  Gemini Power Control driver
+ *
+ *  Copyright (C) 2009 Janos Laube <janos.dev@gmail.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/reboot.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <mach/hardware.h>
+
+#define DRV_VERSION		0.1
+
+#define GEMINI_PWC_ID		0x00010500
+#define	GEMINI_PWC_IDREG	0x00
+#define	GEMINI_PWC_CTRLREG	0x04
+#define	GEMINI_PWC_STATREG	0x08
+#define	GEMINI_POWERBUTTON	0x40
+
+struct gemini_pwc
+{
+	void __iomem*	pwc_base;
+	int		pwc_irq;
+};
+
+static spinlock_t pwc_lock;
+/* work around bad designed hardware, the IB-4220-B powerbutton seems not
+ * to be debounced very well
+ */
+static int pwc_poweroff_issued = 0;
+
+static void gemini_power_off(void)
+{
+	unsigned int reg;
+	printk("gemini_pwc: power off\n");
+	reg = readl(IO_ADDRESS(GEMINI_POWER_CTRL_BASE) + GEMINI_PWC_CTRLREG);
+	writel(reg | BIT(2) | BIT(1),
+		IO_ADDRESS(GEMINI_POWER_CTRL_BASE) + GEMINI_PWC_CTRLREG);
+	reg &= ~BIT(1);
+	reg |= BIT(0);
+	writel(reg | BIT(2),
+		IO_ADDRESS(GEMINI_POWER_CTRL_BASE) + GEMINI_PWC_CTRLREG);
+}
+
+static irqreturn_t gemini_pwc_interrupt(int irq, void* dev)
+{
+	unsigned int reg, src;
+
+	spin_lock_irq(&pwc_lock);
+	/* clear pwc interrupt */
+	writel(readl(IO_ADDRESS(GEMINI_POWER_CTRL_BASE) + GEMINI_PWC_CTRLREG)
+		| (1 << 2), IO_ADDRESS(GEMINI_POWER_CTRL_BASE) +
+		GEMINI_PWC_CTRLREG);
+	reg = readl(IO_ADDRESS(GEMINI_INTERRUPT_BASE) + 0x08);
+	reg |= (1 << IRQ_PWR);
+	writel(reg, IO_ADDRESS(GEMINI_INTERRUPT_BASE) + 0x08);
+	barrier();
+
+	src = readl(IO_ADDRESS(GEMINI_POWER_CTRL_BASE) +
+		GEMINI_PWC_STATREG) & 0x70;
+	if ((src == GEMINI_POWERBUTTON) && (!pwc_poweroff_issued))
+	{
+		printk("gemini_pwc: shutting down machine\n");
+		orderly_poweroff(1);
+		pwc_poweroff_issued = 1;
+	}
+	spin_unlock_irq(&pwc_lock);
+	return IRQ_HANDLED;
+}
+
+static int __devinit gemini_pwc_probe(struct platform_device *pdev)
+{
+	struct gemini_pwc *pwc;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	int ret;
+	unsigned int reg;
+
+	pwc = kzalloc(sizeof(struct gemini_pwc), GFP_KERNEL);
+	if (unlikely(!pwc))
+		return -ENOMEM;
+	platform_set_drvdata(pdev, pwc);
+
+	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!res)
+	{
+		ret = -ENODEV;
+		goto err;
+	}
+	pwc->pwc_irq = res->start;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+	{
+		ret = -ENODEV;
+		goto err;
+	}
+	pwc->pwc_base =	devm_ioremap(&pdev->dev, res->start,
+		res->end - res->start + 1);
+
+	reg = readl(pwc->pwc_base + GEMINI_PWC_IDREG);
+	reg = reg & 0xFFFFFF00;
+	if (reg != GEMINI_PWC_ID)
+	{
+		ret = -ENODEV;
+		goto wrongid;
+	}
+
+	pm_power_off = gemini_power_off;
+
+	/* clear pwc interrupt */
+	writel(readl(pwc->pwc_base + GEMINI_PWC_CTRLREG)
+		| (1 << 2), pwc->pwc_base + GEMINI_PWC_CTRLREG);
+	reg = readl(IO_ADDRESS(GEMINI_INTERRUPT_BASE)+0x08);
+	reg |= (1 << IRQ_PWR);
+	writel(reg, IO_ADDRESS(GEMINI_INTERRUPT_BASE)+0x08);
+	barrier();
+	mdelay(1);
+
+	ret = request_irq(pwc->pwc_irq, gemini_pwc_interrupt, IRQF_DISABLED,
+		pdev->name, dev);
+	if (unlikely(ret))
+		goto err;
+
+	/* enable pwc device */
+	writel(readl(pwc->pwc_base + GEMINI_PWC_CTRLREG)
+			| (1 << 1), pwc->pwc_base + GEMINI_PWC_CTRLREG);
+
+	return 0;
+
+wrongid:
+	printk("gemini_pwc: wrong PWC id\n");
+err:
+	kfree(pwc);
+	return ret;
+}
+
+static int __devexit gemini_pwc_remove(struct platform_device *pdev)
+{
+	struct gemini_pwc *pwc = platform_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+
+	pm_power_off = 0;
+	free_irq(pwc->pwc_irq, dev);
+	platform_set_drvdata(pdev, NULL);
+	kfree(pwc);
+
+	return 0;
+}
+
+static struct platform_driver gemini_pwc_driver = {
+	.driver		= {
+		.name	= "gemini_pwc",
+		.owner	= THIS_MODULE,
+	},
+	.probe		= gemini_pwc_probe,
+	.remove		= __devexit_p(gemini_pwc_remove),
+};
+
+static int __init gemini_pwc_init(void)
+{
+	return platform_driver_register(&gemini_pwc_driver);
+}
+
+static void __exit gemini_pwc_exit(void)
+{
+	platform_driver_unregister(&gemini_pwc_driver);
+}
+
+module_init(gemini_pwc_init);
+module_exit(gemini_pwc_exit);
+
+MODULE_AUTHOR("Janos Laube <janos.dev@gmail.com>");
+MODULE_ALIAS("platform:gemini_pwc");
+MODULE_DESCRIPTION("Driver for the Gemini Power Control device");
+MODULE_VERSION(DRV_VERSION);
+MODULE_LICENSE("GPL");