[PATCH i-g-t v6 1/5] lib/igt_device_scan: Add support for the device filter

[Soham Purkait]

     Add support for the device filter based on
driver string, device type (integrated or discrete)
and card number.

v5 : Add device filter to filter out
     matching devices.           (Zbigniew)

v6 : Move device filter with Separate 
     commit.                     (Zbigniew)

Signed-off-by: Soham Purkait <soham.purkait at intel.com>
---
 lib/igt_device_scan.c | 58 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/lib/igt_device_scan.c b/lib/igt_device_scan.c
index 3f26a1737..ea14d8e23 100644
--- a/lib/igt_device_scan.c
+++ b/lib/igt_device_scan.c
@@ -1709,6 +1709,58 @@ static struct igt_list_head *filter_sriov(const struct filter_class *fcls,
 	return &igt_devs.filtered;
 }
 
+/*
+ * Find appropriate gpu device through matching driver, device type and
+ * card filter arguments.
+ */
+static struct igt_list_head *filter_device(const struct filter_class *fcls,
+					   const struct filter *filter)
+{
+	struct igt_device *dev;
+	int card = -1;
+	(void)fcls;
+
+	DBG("filter device\n");
+
+	if (filter->data.card) {
+		sscanf(filter->data.card, "%d", &card);
+		if (card < 0)
+			return &igt_devs.filtered;
+	} else {
+		card = -1;
+	}
+
+	igt_list_for_each_entry(dev, &igt_devs.all, link) {
+
+		/* Skip if 'driver' doesn't match */
+		if (filter->data.driver && !strequal(filter->data.driver, dev->driver))
+			continue;
+
+		/* Skip if 'device' doesn't match */
+		if (filter->data.device && !is_device_matched(dev, filter->data.device))
+			continue;
+
+		/* We get n-th card */
+		if (!card) {
+			struct igt_device *dup = duplicate_device(dev);
+
+			igt_list_add_tail(&dup->link, &igt_devs.filtered);
+			break;
+		}
+		/* Include all the card */
+		else if (card == -1) {
+			struct igt_device *dup = duplicate_device(dev);
+
+			igt_list_add(&dup->link, &igt_devs.filtered);
+		} else
+			card--;
+	}
+
+	DBG("Filter device filtered size: %d\n", igt_list_length(&igt_devs.filtered));
+
+	return &igt_devs.filtered;
+}
+
 static bool sys_path_valid(const struct filter_class *fcls,
 			   const struct filter *filter)
 {
@@ -1750,6 +1802,12 @@ static struct filter_class filter_definition_list[] = {
 		.help = "sriov:[vendor=%04x/name][,device=%04x][,card=%d][,pf=%d][,vf=%d]",
 		.detail = "find pf or vf\n",
 	},
+	{
+		.name = "device",
+		.filter_function = filter_device,
+		.help = "device:[driver=name][,device=type][,card=%d]",
+		.detail = "find device by driver name, device type and card number\n",
+	},
 	{
 		.name = NULL,
 	},
-- 
2.34.1