[PATCH 2/8] DSPBRIDGE: sysfs entry for global driver state

[Omar Ramirez Luna <omar.ramirez@ti.com>]

This patch creates a new sysfs entry to query the driver
state without making any bridge direct call, this is
useful to monitor driver state without creating any handle
to bridge driver.

Signed-off-by: Omar Ramirez Luna <omar.ramirez@ti.com>
---
 drivers/dsp/bridge/rmgr/drv_interface.c |   87 +++++++++++++++++++++++++++++++
 1 files changed, 87 insertions(+), 0 deletions(-)

diff --git a/drivers/dsp/bridge/rmgr/drv_interface.c b/drivers/dsp/bridge/rmgr/drv_interface.c
index c853854..3a4d058 100644
--- a/drivers/dsp/bridge/rmgr/drv_interface.c
+++ b/drivers/dsp/bridge/rmgr/drv_interface.c
@@ -58,11 +58,13 @@
 #include <linux/init.h>
 #include <linux/moduleparam.h>
 #include <linux/cdev.h>
+#include <linux/kobject.h>
 
 /*  ----------------------------------- DSP/BIOS Bridge */
 #include <dspbridge/std.h>
 #include <dspbridge/dbdefs.h>
 #include <dspbridge/errbase.h>
+#include <_tiomap.h>
 
 /*  ----------------------------------- Trace & Debug */
 #include <dspbridge/gt.h>
@@ -148,6 +150,10 @@ static int omap34xxbridge_suspend_lockout(
 }
 #endif
 
+/* Sysfs interface */
+static void bridge_create_sysfs(struct platform_device *pdev);
+static void bridge_destroy_sysfs(struct platform_device *pdev);
+
 #ifdef DEBUG
 module_param(GT_str, charp, 0);
 MODULE_PARM_DESC(GT_str, "GT string, default = NULL");
@@ -297,6 +303,9 @@ static int __devinit omap34xx_bridge_probe(struct platform_device *pdev)
 	device_create(bridge_class, NULL, MKDEV(driver_major, driver_minor),
 			NULL, "DspBridge");
 
+	/* Create sysfs interface */
+	bridge_create_sysfs(pdev);
+
 	GT_init();
 	GT_create(&driverTrace, "LD");
 
@@ -454,6 +463,9 @@ func_cont:
 	SERVICES_Exit();
 	GT_exit();
 
+	/* Remove driver sysfs entries */
+	bridge_destroy_sysfs(pdev);
+
 	devno = MKDEV(driver_major, driver_minor);
 	if (bridge_device) {
 		cdev_del(&bridge_device->cdev);
@@ -677,6 +689,81 @@ DSP_STATUS DRV_RemoveAllResources(HANDLE hPCtxt)
 }
 #endif
 
+/*
+ * Sysfs
+ */
+static ssize_t drv_state_show(struct device *dev, struct device_attribute *attr,
+				char *buf)
+{
+	struct WMD_DEV_CONTEXT *dev_ctxt;
+	struct DEV_OBJECT *dev_obj = NULL;
+	char *drv_state = "unknown";
+
+	dev_obj = (struct DEV_OBJECT *)DRV_GetFirstDevObject();
+	DEV_GetWMDContext(dev_obj, &dev_ctxt);
+
+	if (!dev_ctxt)
+		goto err;
+
+	switch (dev_ctxt->dwBrdState) {
+	case BRD_STOPPED:
+		drv_state = "stopped";
+		break;
+	case BRD_IDLE:
+		drv_state = "idle";
+		break;
+	case BRD_RUNNING:
+		drv_state = "running";
+		break;
+	case BRD_LOADED:
+		drv_state = "loaded";
+		break;
+	case BRD_SLEEP_TRANSITION:
+		drv_state = "sleep transition";
+		break;
+	case BRD_HIBERNATION:
+		drv_state = "hibernation";
+		break;
+	case BRD_RETENTION:
+		drv_state = "retention";
+		break;
+	case BRD_DSP_HIBERNATION:
+		drv_state = "self initiated hibernation";
+		break;
+	case BRD_ERROR:
+		drv_state = "error";
+		break;
+	}
+
+err:
+	return sprintf(buf, "%s\n", drv_state);
+}
+static DEVICE_ATTR(drv_state, S_IRUGO, drv_state_show, NULL);
+
+static struct attribute *attrs[] = {
+	&dev_attr_drv_state.attr,
+	NULL,
+};
+
+static struct attribute_group attr_group = {
+	.attrs = attrs,
+};
+
+static void bridge_create_sysfs(struct platform_device *pdev)
+{
+	int error;
+
+	error = sysfs_create_group(&pdev->dev.kobj, &attr_group);
+
+	if (error)
+		kobject_put(&pdev->dev.kobj);
+}
+
+static void bridge_destroy_sysfs(struct platform_device *pdev)
+{
+	sysfs_remove_group(&pdev->dev.kobj, &attr_group);
+}
+
 /* Bridge driver initialization and de-initialization functions */
 module_init(bridge_init);
 module_exit(bridge_exit);
-- 
1.6.2.4