[igt-dev] [PATCH i-g-t v4 1/3] lib/ioctl_wrapper: Add i915_get_param helper

[Lukasz Kalamarz]

getparam is used in few places across IGT, but no helper function
is used to reduce code duplication.

v2: Added doc part and changed return value in case of error
v3: Renamed function to i915_get_param, created internal error
checking function and helper function to check if given feature
is enabled.

Signed-off-by: Lukasz Kalamarz <lukasz.kalamarz at intel.com>

Cc: Michal Winiarski <michal.winiarski at intel.com>
Cc: Katarzyna Dec <katarzyna.dec at intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
Cc: Petri Latvala <Petri.latvala at intel.com>
Cc: Eric Anholt <eric at anholt.net>
Cc: Antonio Argenziano <antonio.argenziano at intel.com>
Cc: Ankit K Nautiyal <ankit.k.nautiyal at intel.com>
---
 lib/ioctl_wrappers.c | 50 ++++++++++++++++++++++++++++++++++++++++++++
 lib/ioctl_wrappers.h |  2 ++
 2 files changed, 52 insertions(+)

diff --git a/lib/ioctl_wrappers.c b/lib/ioctl_wrappers.c
index 9f255508..b48dad5b 100644
--- a/lib/ioctl_wrappers.c
+++ b/lib/ioctl_wrappers.c
@@ -468,6 +468,56 @@ void gem_sync(int fd, uint32_t handle)
 	errno = 0;
 }
 
+static int
+__i915_get_param(int fd, struct drm_i915_getparam *gp)
+{
+	int err;
+
+	err = 0;
+	if (igt_ioctl(fd, DRM_IOCTL_I915_GETPARAM, gp))
+		err = -errno;
+
+	errno = 0;
+	return err;
+}
+
+/**
+ * i915_get_param:
+ * @fd: open i915 drm file descriptor
+ * @param: drm parameter we want to read
+ *
+ * Helper function that execute GETPARAM ioctl for a given parameter.
+ *
+ * Return: Read value from GETPARAM
+ */
+int i915_get_param(int fd, uint32_t param)
+{
+	int value;
+	drm_i915_getparam_t gp = {
+		.param = param,
+		.value = &value
+	};
+
+	igt_assert_eq(__i915_get_param(fd, &gp), 0);
+
+	return value;
+}
+
+/**
+ * i915_has_feature:
+ * @fd: open i915 drm file descriptor
+ * @param: drm parameter we want to read
+ *
+ * Helper function that check if given functionality is enabled.
+ * Check is done via getparam IOCTL.
+ *
+ * Return: Value whether feature is enabled or not
+ */
+
+bool i915_has_feature(int fd, uint32_t param)
+{
+	return i915_get_param(fd, param) > 0;
+}
 
 bool gem_create__has_stolen_support(int fd)
 {
diff --git a/lib/ioctl_wrappers.h b/lib/ioctl_wrappers.h
index b22b36b0..c314a070 100644
--- a/lib/ioctl_wrappers.h
+++ b/lib/ioctl_wrappers.h
@@ -74,6 +74,8 @@ int __gem_set_domain(int fd, uint32_t handle, uint32_t read, uint32_t write);
 void gem_set_domain(int fd, uint32_t handle, uint32_t read, uint32_t write);
 int gem_wait(int fd, uint32_t handle, int64_t *timeout_ns);
 void gem_sync(int fd, uint32_t handle);
+int i915_get_param(int fd, uint32_t param);
+bool i915_has_feature(int fd, uint32_t param);
 bool gem_create__has_stolen_support(int fd);
 uint32_t __gem_create_stolen(int fd, uint64_t size);
 uint32_t gem_create_stolen(int fd, uint64_t size);
-- 
2.17.2