[PATCH i-g-t v6 2/4] lib/igt_pm: Add helper to get/set auto_suspenddelay_ms

[Anshuman Gupta <anshuman.gupta@intel.com>]

Sometimes we want to test pm igt test with an explicit auto
suspend delay, therefore adding helpers to get/set the pci_dev
auto_suspenddelay_ms.

v2:
close delay_fd. [Kamil]

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
---
 lib/igt_pm.c | 56 +++++++++++++++++++++++++++++++++++++++++-----------
 lib/igt_pm.h |  2 ++
 2 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/lib/igt_pm.c b/lib/igt_pm.c
index c2d98fceb..bb8563214 100644
--- a/lib/igt_pm.c
+++ b/lib/igt_pm.c
@@ -1068,18 +1068,6 @@ static void igt_pm_write_power_attr(int fd, const char *val, int len)
 	igt_assert(strncmp(buf, val, len) == 0);
 }
 
-static int igt_pm_get_autosuspend_delay(struct pci_device *pci_dev)
-{
-	char delay_str[64];
-	int delay, delay_fd;
-
-	delay_fd = igt_pm_get_power_attr_fd(pci_dev, "autosuspend_delay_ms");
-	if (igt_pm_read_power_attr(delay_fd, delay_str, 64, true))
-		igt_assert(sscanf(delay_str, "%d", &delay) > 0);
-
-	return delay;
-}
-
 static void
 igt_pm_setup_pci_dev_power_attrs(struct pci_device *pci_dev,
 				 struct igt_pm_pci_dev_pwrattr *pwrattr, int delay_ms)
@@ -1165,6 +1153,50 @@ igt_pm_setup_pci_card_power_attrs(struct pci_device *pci_dev, bool save_attrs, i
 	pci_iterator_destroy(iter);
 }
 
+/**
+ * igt_pm_get_autosuspend_delay:
+ * @pci_dev: pci_dev.
+ * Get pci_dev autosuspend delay value from pci sysfs "autosuspend_delay_ms".
+ *
+ * Returns:
+ * autosuspend_delay_ms.
+ */
+int igt_pm_get_autosuspend_delay(struct pci_device *pci_dev)
+{
+	char delay_str[64];
+	int delay, delay_fd;
+
+	delay_fd = igt_pm_get_power_attr_fd(pci_dev, "autosuspend_delay_ms");
+	if (igt_pm_read_power_attr(delay_fd, delay_str, 64, true))
+		igt_assert(sscanf(delay_str, "%d", &delay) > 0);
+
+	close(delay_fd);
+	return delay;
+}
+
+/**
+ * igt_pm_set_autosuspend_delay:
+ * @pci_dev: pci_dev.
+ * @delay_ms: autosuspend delay in ms.
+ * Set pci_dev autosuspend delay value through pci sysfs "autosuspend_delay_ms".
+ */
+void igt_pm_set_autosuspend_delay(struct pci_device *pci_dev, int delay_ms)
+{
+	char delay_str[64];
+	int delay_fd;
+
+	delay_fd = igt_pm_get_power_attr_fd(pci_dev, "autosuspend_delay_ms");
+
+	if (delay_ms >= 0) {
+		int wc;
+
+		wc = snprintf(delay_str, 64, "%d\n", delay_ms);
+		igt_pm_write_power_attr(delay_fd, delay_str, wc);
+	}
+
+	close(delay_fd);
+}
+
 /**
  * igt_pm_enable_pci_card_runtime_pm:
  * @root: root port pci_dev.
diff --git a/lib/igt_pm.h b/lib/igt_pm.h
index 538b6e39e..91ee05cd1 100644
--- a/lib/igt_pm.h
+++ b/lib/igt_pm.h
@@ -82,6 +82,8 @@ int igt_pm_get_pcie_acpihp_slot(struct pci_device *pci_dev);
 bool igt_pm_acpi_d3cold_supported(struct pci_device *pci_dev);
 enum igt_acpi_d_state
 igt_pm_get_acpi_real_d_state(struct pci_device *pci_dev);
+int igt_pm_get_autosuspend_delay(struct pci_device *pci_dev);
+void igt_pm_set_autosuspend_delay(struct pci_device *pci_dev, int delay_ms);
 void igt_pm_enable_pci_card_runtime_pm(struct pci_device *root,
 				       struct pci_device *i915);
 void igt_pm_get_d3cold_allowed(const char *pci_slot_name, uint32_t *value);
-- 
2.25.1