intel_mid_powerbtn: add power button driver for Medfield platform (#3)

The power button is connected to MSIC on Medfield, we will get two
interrupts from IOAPIC when pressing or releasing the power button.

Signed-off-by: Hong Liu <hong.liu@intel.com>
[Minor fixes as noted by Dmitry]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

drivers/platform/x86/Kconfig

@@ -616,6 +616,14 @@ config GPIO_INTEL_PMIC
 	  Say Y here to support GPIO via the SCU IPC interface
 	  on Intel MID platforms.
 
+config INTEL_MID_POWER_BUTTON
+	tristate "power button driver for Intel MID platforms"
+	depends on INTEL_SCU_IPC
+	help
+	  This driver handles the power button on the Intel MID platforms.
+
+	  If unsure, say N.
+
 config RAR_REGISTER
 	bool "Restricted Access Region Register Driver"
 	depends on PCI && X86_MRST

drivers/platform/x86/Makefile

@@ -36,3 +36,4 @@ obj-$(CONFIG_GPIO_INTEL_PMIC)	+= intel_pmic_gpio.o
 obj-$(CONFIG_XO1_RFKILL)	+= xo1-rfkill.o
 obj-$(CONFIG_XO15_EBOOK)	+= xo15-ebook.o
 obj-$(CONFIG_IBM_RTL)		+= ibm_rtl.o
+obj-$(CONFIG_INTEL_MFLD_THERMAL)	+= intel_mid_thermal.o

drivers/platform/x86/intel_mid_powerbtn.c

@@ -0,0 +1,148 @@
+/*
+ * Power button driver for Medfield.
+ *
+ * Copyright (C) 2010 Intel Corp
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <asm/intel_scu_ipc.h>
+
+#define DRIVER_NAME "msic_power_btn"
+
+#define MSIC_IRQ_STAT	0x02
+  #define MSIC_IRQ_PB	(1 << 0)
+#define MSIC_PB_CONFIG	0x3e
+#define MSIC_PB_STATUS	0x3f
+  #define MSIC_PB_LEVEL (1 << 3) /* 1 - release, 0 - press */
+
+struct mfld_pb_priv {
+	struct input_dev *input;
+	unsigned int irq;
+};
+
+static irqreturn_t mfld_pb_isr(int irq, void *dev_id)
+{
+	struct mfld_pb_priv *priv = dev_id;
+	int ret;
+	u8 pbstat;
+
+	ret = intel_scu_ipc_ioread8(MSIC_PB_STATUS, &pbstat);
+	if (ret < 0)
+		return IRQ_HANDLED;
+
+	input_event(priv->input, EV_KEY, KEY_POWER, !(pbstat & MSIC_PB_LEVEL));
+	input_sync(priv->input);
+
+	return IRQ_HANDLED;
+}
+
+static int __devinit mfld_pb_probe(struct platform_device *pdev)
+{
+	struct mfld_pb_priv *priv;
+	struct input_dev *input;
+	int irq;
+	int error;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return -EINVAL;
+
+	priv = kzalloc(sizeof(struct mfld_pb_priv), GFP_KERNEL);
+	input = input_allocate_device();
+	if (!priv || !input) {
+		error = -ENOMEM;
+		goto err_free_mem;
+	}
+
+	priv->input = input;
+	priv->irq = irq;
+
+	input->name = pdev->name;
+	input->phys = "power-button/input0";
+	input->id.bustype = BUS_HOST;
+	input->dev.parent = &pdev->dev;
+
+	input_set_capability(input, EV_KEY, KEY_POWER);
+
+	error = request_threaded_irq(priv->irq, NULL, mfld_pb_isr,
+				     0, DRIVER_NAME, priv);
+	if (error) {
+		dev_err(&pdev->dev,
+			"unable to request irq %d for mfld power button\n",
+			irq);
+		goto err_free_mem;
+	}
+
+	error = input_register_device(input);
+	if (error) {
+		dev_err(&pdev->dev,
+			"unable to register input dev, error %d\n", error);
+		goto err_free_irq;
+	}
+
+	platform_set_drvdata(pdev, priv);
+	return 0;
+
+err_free_irq:
+	free_irq(priv->irq, priv);
+err_free_mem:
+	input_free_device(input);
+	kfree(priv);
+	return error;
+}
+
+static int __devexit mfld_pb_remove(struct platform_device *pdev)
+{
+	struct mfld_pb_priv *priv = platform_get_drvdata(pdev);
+
+	free_irq(priv->irq, priv);
+	input_unregister_device(priv->input);
+	kfree(priv);
+
+	platform_set_drvdata(pdev, NULL);
+	return 0;
+}
+
+static struct platform_driver mfld_pb_driver = {
+	.driver = {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+	},
+	.probe	= mfld_pb_probe,
+	.remove	= __devexit_p(mfld_pb_remove),
+};
+
+static int __init mfld_pb_init(void)
+{
+	return platform_driver_register(&mfld_pb_driver);
+}
+module_init(mfld_pb_init);
+
+static void __exit mfld_pb_exit(void)
+{
+	platform_driver_unregister(&mfld_pb_driver);
+}
+module_exit(mfld_pb_exit);
+
+MODULE_AUTHOR("Hong Liu <hong.liu@intel.com>");
+MODULE_DESCRIPTION("Intel Medfield Power Button Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRIVER_NAME);