From a7ac4fced215c7c371c42effcfddf7ed7121b6fb Mon Sep 17 00:00:00 2001
From: Todd Poynor <toddpoynor@google.com>
Date: Wed, 4 Aug 2010 20:25:59 -0700
Subject: [PATCH] cpcap: suspend/resume

Disable cpcap interrupts at suspend and re-enable at resume, to avoid
processing interrupts while the SPI controller is suspended.

Change-Id: I26676b8ce8983bf5477f169a15d811c474c6f5a4
Signed-off-by: Todd Poynor <toddpoynor@google.com>
---
 drivers/mfd/cpcap-core.c  | 27 +++++++++++++++++++++++++++
 drivers/mfd/cpcap-irq.c   | 18 ++++++++++++++++++
 include/linux/spi/cpcap.h |  6 ++++++
 3 files changed, 51 insertions(+)

diff --git a/drivers/mfd/cpcap-core.c b/drivers/mfd/cpcap-core.c
index 78b4fbb9efc3..5015e390b77f 100644
--- a/drivers/mfd/cpcap-core.c
+++ b/drivers/mfd/cpcap-core.c
@@ -27,6 +27,7 @@
 #include <linux/reboot.h>
 #include <linux/notifier.h>
 #include <linux/delay.h>
+#include <linux/pm.h>
 
 struct cpcap_driver_info {
 	struct list_head list;
@@ -38,6 +39,11 @@ static int ioctl(struct inode *inode,
 static int __devinit cpcap_probe(struct spi_device *spi);
 static int __devexit cpcap_remove(struct spi_device *spi);
 
+#ifdef CONFIG_PM
+static int cpcap_suspend(struct spi_device *spi, pm_message_t mesg);
+static int cpcap_resume(struct spi_device *spi);
+#endif
+
 const static struct file_operations cpcap_fops = {
 	.owner = THIS_MODULE,
 	.ioctl = ioctl,
@@ -57,6 +63,10 @@ static struct spi_driver cpcap_driver = {
 		   },
 	.probe = cpcap_probe,
 	.remove = __devexit_p(cpcap_remove),
+#ifdef CONFIG_PM
+	.suspend = cpcap_suspend,
+	.resume = cpcap_resume,
+#endif
 };
 
 static struct platform_device cpcap_adc_device = {
@@ -455,6 +465,23 @@ static void cpcap_shutdown(void)
 	spi_unregister_driver(&cpcap_driver);
 }
 
+#ifdef CONFIG_PM
+static int cpcap_suspend(struct spi_device *spi, pm_message_t mesg)
+{
+
+	struct cpcap_device *cpcap = spi_get_drvdata(spi);
+
+	return cpcap_irq_suspend(cpcap);
+}
+
+static int cpcap_resume(struct spi_device *spi)
+{
+	struct cpcap_device *cpcap = spi_get_drvdata(spi);
+
+	return cpcap_irq_resume(cpcap);
+}
+#endif
+
 subsys_initcall(cpcap_init);
 module_exit(cpcap_shutdown);
 
diff --git a/drivers/mfd/cpcap-irq.c b/drivers/mfd/cpcap-irq.c
index 9c133be68126..397caaae20a7 100644
--- a/drivers/mfd/cpcap-irq.c
+++ b/drivers/mfd/cpcap-irq.c
@@ -630,3 +630,21 @@ int cpcap_irq_sense(struct cpcap_device *cpcap,
 	return ((val & EVENT_MASK(irq)) != 0) ? 1 : 0;
 }
 EXPORT_SYMBOL_GPL(cpcap_irq_sense);
+
+#ifdef CONFIG_PM
+int cpcap_irq_suspend(struct cpcap_device *cpcap)
+{
+	struct spi_device *spi = cpcap->spi;
+
+	disable_irq(spi->irq);
+	return 0;
+}
+
+int cpcap_irq_resume(struct cpcap_device *cpcap)
+{
+	struct spi_device *spi = cpcap->spi;
+
+	enable_irq(spi->irq);
+	return 0;
+}
+#endif
diff --git a/include/linux/spi/cpcap.h b/include/linux/spi/cpcap.h
index d0d82c4291ba..b2d9fcf303dd 100644
--- a/include/linux/spi/cpcap.h
+++ b/include/linux/spi/cpcap.h
@@ -717,6 +717,12 @@ int cpcap_irq_mask_get(struct cpcap_device *cpcap, enum cpcap_irqs int_event);
 int cpcap_irq_sense(struct cpcap_device *cpcap, enum cpcap_irqs int_event,
 		    unsigned char clear);
 
+#ifdef CONFIG_PM
+int cpcap_irq_suspend(struct cpcap_device *cpcap);
+
+int cpcap_irq_resume(struct cpcap_device *cpcap);
+#endif
+
 int cpcap_adc_sync_read(struct cpcap_device *cpcap,
 			struct cpcap_adc_request *request);
 
-- 
2.34.1