[Intel-gfx] [PATCH i-g-t v2 1/3] lib/igt_pm: Refactor get firmware_node fd

[Anshuman Gupta]

Created igt_pm_open_pci_firmware_node() to refactor
the retrieving the firmware_node fd code.

igt_pm_open_pci_firmware_node() will be used by other
firmware_node consumers.

While doing that fixed the leaked fd as well.

v2:
- return false instead of igt_require on no firmware_node_fd. [Kamil]
- use igt_assert() when failed to open 'real_power_state' on error
  other then ENONET.

Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
---
 lib/igt_pm.c | 36 +++++++++++++++++++++++++-----------
 1 file changed, 25 insertions(+), 11 deletions(-)

diff --git a/lib/igt_pm.c b/lib/igt_pm.c
index 1e6e9ed3f..4f0cfbdd1 100644
--- a/lib/igt_pm.c
+++ b/lib/igt_pm.c
@@ -863,6 +863,20 @@ bool i915_output_is_lpsp_capable(int drm_fd, igt_output_t *output)
 	return strstr(buf, "LPSP: capable");
 }
 
+static int igt_pm_open_pci_firmware_node(struct pci_device *pci_dev)
+{
+	char name[PATH_MAX];
+	int dir;
+
+	snprintf(name, PATH_MAX,
+		 "/sys/bus/pci/devices/%04x:%02x:%02x.%01x/firmware_node",
+		 pci_dev->domain, pci_dev->bus, pci_dev->dev, pci_dev->func);
+
+	dir = open(name, O_RDONLY);
+
+	return dir;
+}
+
 /**
  * igt_pm_acpi_d3cold_supported:
  * @pci_dev: root port pci_dev.
@@ -873,23 +887,23 @@ bool i915_output_is_lpsp_capable(int drm_fd, igt_output_t *output)
  */
 bool igt_pm_acpi_d3cold_supported(struct pci_device *pci_dev)
 {
-	char name[PATH_MAX];
-	int dir, fd;
-
-	snprintf(name, PATH_MAX,
-		 "/sys/bus/pci/devices/%04x:%02x:%02x.%01x/firmware_node",
-		 pci_dev->domain, pci_dev->bus, pci_dev->dev, pci_dev->func);
+	int firmware_node_fd, fd;
 
-	dir = open(name, O_RDONLY);
-	igt_require(dir > 0);
+	firmware_node_fd = igt_pm_open_pci_firmware_node(pci_dev);
+	if (firmware_node_fd < 0)
+		return false;
 
 	/* BIOS need to enable ACPI D3Cold Support.*/
-	fd = openat(dir, "real_power_state", O_RDONLY);
-	if (fd < 0 && errno == ENOENT)
+	fd = openat(firmware_node_fd, "real_power_state", O_RDONLY);
+	if (fd < 0 && errno == ENOENT) {
+		close(firmware_node_fd);
 		return false;
+	}
 
-	igt_require(fd > 0);
+	igt_assert(errno > 0);
 
+	close(firmware_node_fd);
+	close(fd);
 	return true;
 }
 
-- 
2.25.1