u5500 : modem crashdump detection driver

Detects modem crashdump ready and informs userspace

ST-Ericsson Linux next: NA
ST-Ericsson ID: 354626
ST-Ericsson FOSS-OUT ID: Trivial

Change-Id: I204eeb48b7353509b07b9e3c6ec08bc7026985fa
Signed-off-by: Bibek Basu <bibek.basu@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/34170
Reviewed-by: QATOOLS
Reviewed-by: QABUILD
Reviewed-by: Sandeep TRIPATHY <sandeep.tripathy@stericsson.com>
Tested-by: Sandeep TRIPATHY <sandeep.tripathy@stericsson.com>
Reviewed-by: Srinidhi KASAGAR <srinidhi.kasagar@stericsson.com>

3 files changed, 203 insertions, 1 deletions

diff --git a/drivers/modem/Kconfig b/drivers/modem/Kconfig
index 323ef88af18..be8476ed0f9 100644
--- a/drivers/modem/Kconfig
+++ b/drivers/modem/Kconfig
@@ -1,6 +1,6 @@
 config MODEM
         bool "Modem Access Framework"
-        default n
+        default y
         help
          Add support for Modem Access Framework. It allows different
 	 platform specific drivers to register modem access mechanisms
@@ -8,6 +8,17 @@ config MODEM
 
 	 If unsure, say N.
 
+config MODEM_U5500_MCDD
+	tristate "Modem crash dump detection driver for STE U5500 platform"
+	depends on (UX500_SOC_DB5500 && U5500_MODEM_IRQ && MODEM)
+	default y
+	help
+	 Add support for Modem crash detection
+	 driver for  STE U5500 platform.
+	 And inform userspace.
+
+         If unsure, say N.
+
 config MODEM_U8500
 	bool "Modem Access driver for STE U8500 platform"
 	depends on MODEM
diff --git a/drivers/modem/Makefile b/drivers/modem/Makefile
index a7c1df50074..82921988f27 100644
--- a/drivers/modem/Makefile
+++ b/drivers/modem/Makefile
@@ -3,3 +3,4 @@ obj-$(CONFIG_MODEM_U8500) += modem_u8500.o
 obj-$(CONFIG_U8500_SHRM)  += shrm/
 obj-$(CONFIG_MODEM_M6718) += modem_m6718.o
 obj-$(CONFIG_MODEM_M6718_SPI) += m6718_spi/
+obj-$(CONFIG_MODEM_U5500_MCDD)  += mcdd.o
diff --git a/drivers/modem/mcdd.c b/drivers/modem/mcdd.c
new file mode 100644
index 00000000000..d291944e810
--- /dev/null
+++ b/drivers/modem/mcdd.c
@@ -0,0 +1,190 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * Modem Crash Detection Driver
+ *
+ * Author:Bibek Basu <bibek.basu@stericsson.com> for ST-Ericsson
+ *
+ * License terms:GNU General Public License (GPLv2)version 2
+ */
+
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/miscdevice.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/sched.h>
+#include <linux/poll.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+
+#define MCDD_INTERRUPT_CLEAR (1 << 13)
+#define MODEM_CRASH_EVT  1
+
+struct mcdd_data {
+	bool	modem_event;
+	u32   event_type;
+	wait_queue_head_t  readq;
+	spinlock_t	lock;
+	void __iomem *remap_intcon;
+	struct device *dev;
+	struct miscdevice misc_dev;
+};
+
+static struct mcdd_data *mcdd;
+
+static irqreturn_t mcdd_interrupt_cb(int irq, void *dev)
+{
+	writel(MCDD_INTERRUPT_CLEAR, (u32 *)mcdd->remap_intcon);
+	spin_lock(&mcdd->lock);
+	mcdd->modem_event = true;
+	mcdd->event_type = MODEM_CRASH_EVT;
+	spin_unlock(&mcdd->lock);
+	wake_up_interruptible(&mcdd->readq);
+	return IRQ_HANDLED;
+}
+
+static unsigned int mcdd_select(struct file *filp, poll_table *wait)
+{
+	unsigned int mask = 0;
+	unsigned long flags;
+
+	poll_wait(filp, &mcdd->readq,  wait);
+	spin_lock_irqsave(&mcdd->lock, flags);
+
+	if (mcdd->modem_event == true) {
+		mask |= POLLPRI;
+		mcdd->modem_event = false;
+	}
+	spin_unlock_irqrestore(&mcdd->lock, flags);
+
+	return mask;
+}
+
+static int mcdd_open(struct inode *ino, struct file *filp)
+{
+	/* Do nothing */
+	return 0;
+}
+
+ssize_t mcdd_read(struct file *filp, char __user *buff, size_t size, loff_t *t)
+{
+	if (copy_to_user(buff, &mcdd->event_type, size))
+		return -EFAULT;
+	return 0;
+};
+
+static const struct file_operations mcdd_fops = {
+	.open    = mcdd_open,
+	.poll    = mcdd_select,
+	.read    = mcdd_read,
+	.owner   = THIS_MODULE,
+};
+
+static int __devinit u5500_mcdd_probe(struct platform_device *pdev)
+{
+	struct resource *resource;
+	int ret = 0;
+	int irq;
+
+	mcdd = kzalloc(sizeof(*mcdd), GFP_KERNEL);
+	if (!mcdd) {
+		dev_err(&pdev->dev, "Memory Allocation Failed");
+		return -ENOMEM;
+	}
+	mcdd->dev = &pdev->dev;
+	mcdd->misc_dev.minor = MISC_DYNAMIC_MINOR;
+	mcdd->misc_dev.name = "mcdd";
+	mcdd->misc_dev.fops = &mcdd_fops;
+	spin_lock_init(&mcdd->lock);
+	init_waitqueue_head(&(mcdd->readq));
+
+	/* Get addr for mcdd crash interrupt reset register and ioremap it */
+	resource = platform_get_resource_byname(pdev,
+						IORESOURCE_MEM,
+						"mcdd_intreset_addr");
+	if (resource == NULL) {
+		dev_err(&pdev->dev,
+			"Unable to retrieve mcdd_intreset_addr resource\n");
+		goto exit_free;
+	}
+	mcdd->remap_intcon = ioremap(resource->start, resource_size(resource));
+	if (!mcdd->remap_intcon) {
+		dev_err(&pdev->dev, "Unable to ioremap intcon mbox1\n");
+		ret = -EINVAL;
+		goto exit_free;
+	}
+
+	/* Get IRQ for mcdd mbox interrupt and allocate it */
+	irq = platform_get_irq_byname(pdev, "mcdd_mbox_irq");
+	if (irq < 0) {
+		dev_err(&pdev->dev,
+			"Unable to retrieve mcdd mbox irq resource\n");
+		goto exit_unmap;
+	}
+
+	ret = request_threaded_irq(irq, NULL,
+			mcdd_interrupt_cb, IRQF_NO_SUSPEND | IRQF_ONESHOT,
+			"mcdd", &mcdd);
+	if (ret < 0) {
+		dev_err(&pdev->dev,
+				"Could not allocate irq %d,error %d\n",
+				 irq, ret);
+		goto exit_unmap;
+	}
+
+	ret = misc_register(&mcdd->misc_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "can't misc-register\n");
+		goto exit_unmap;
+	}
+	dev_info(&pdev->dev, "mcdd driver registration done\n");
+	return 0;
+
+exit_unmap:
+	iounmap(mcdd->remap_intcon);
+exit_free:
+	kfree(mcdd);
+	return ret;
+}
+
+static int u5500_mcdd_remove(struct platform_device *pdev)
+{
+	int ret = 0;
+
+	if (mcdd) {
+		iounmap(mcdd->remap_intcon);
+		ret = misc_deregister(&mcdd->misc_dev);
+		kfree(mcdd);
+	}
+	return ret;
+}
+
+static struct platform_driver u5500_mcdd_driver = {
+	.driver = {
+		.name = "u5500-mcdd-modem",
+		.owner = THIS_MODULE,
+	},
+	.probe = u5500_mcdd_probe,
+	.remove = __devexit_p(u5500_mcdd_remove),
+};
+
+static int __init mcdd_init(void)
+{
+	return platform_driver_register(&u5500_mcdd_driver);
+}
+module_init(mcdd_init);
+
+static void __exit mcdd_exit(void)
+{
+	platform_driver_unregister(&u5500_mcdd_driver);
+}
+module_exit(mcdd_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("BIBEK BASU <bibek.basu@stericsson.com>");
+MODULE_DESCRIPTION("Modem Dump Detection Driver");
+MODULE_ALIAS("mcdd driver");