On 12/21/2012 04:27 PM, Pratik Patel wrote:

On Wed, Dec 12, 2012 at 03:43:06PM -0600, Jon Hunter wrote:

quoted

+
+/**
+ * cti_irq_ack - acknowledges the CTI trigger output
+ * @cti: CTI instance
+ *
+ * Acknowledges the CTI trigger output by writting to the appropriate
+ * bit in the CTI interrupt acknowledge register.
+ */
+int cti_irq_ack(struct cti *cti)
+{
+	u32 v;
+
+	if (!cti || !cti->enabled)
+		return -EINVAL;
+
+	v = cti_readl(cti, CTIINTACK);

Just curious if CTIINTACK is a read-write register? This is a
read-only for us.

quoted

+	v |= BIT(cti->trig_out);
+	cti_writel(v, cti, CTIINTACK);
+
+	return 0;
+}
+
+
+static int cti_probe(struct amba_device *dev, const struct amba_id *id)
+{
+	struct cti *cti;
+	struct device_node *np = dev->dev.of_node;
+	int rc;
+
+	if (!np) {
+		dev_err(&dev->dev, "device-tree not found!\n");
+		return -ENODEV;
+	}
+
+	cti = devm_kzalloc(&dev->dev, sizeof(struct cti), GFP_KERNEL);
+	if (!cti) {
+		dev_err(&dev->dev, "memory allocation failed!\n");
+		return -ENOMEM;
+	}
+
+	rc = of_property_read_string_index(np, "arm,cti-name", 0, &cti->name);
+	if (rc) {
+		dev_err(&dev->dev, "no name found for CTI!\n");
+		return rc;
+	}

Shouldn't the CTI driver have some kind of clock management that
it does for itself?

It does by using runtime PM. If you look at the cti_get/put functions,
you will see calls to pm_runtime_get/put. These calls will enable the
AMBA apb-clock. If you need to enable additional clocks then you could
register pm runtime resume/idle call backs to do this.

Cheers
Jon