V4L/DVB (10072): soc-camera: Add signal inversion flags to be used by camera drivers

As reported by Antonio Ospite <ospite@studenti.unina.it> two platforms with a
mt9m111 camera require opposite pixel clock polarity, which means one of them
inverts it. This patch adds support for inversion flags and switches all
available camera drivers to using them.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 34 insertions, 0 deletions

diff --git a/drivers/media/video/soc_camera.c b/drivers/media/video/soc_camera.c
index 5e48c2cc1a44..176017501055 100644
--- a/drivers/media/video/soc_camera.c
+++ b/drivers/media/video/soc_camera.c
@@ -59,6 +59,40 @@ const struct soc_camera_format_xlate *soc_camera_xlate_by_fourcc(
 }
 EXPORT_SYMBOL(soc_camera_xlate_by_fourcc);
 
+/**
+ * soc_camera_apply_sensor_flags() - apply platform SOCAM_SENSOR_INVERT_* flags
+ * @icl:        camera platform parameters
+ * @flags:      flags to be inverted according to platform configuration
+ * @return:     resulting flags
+ */
+unsigned long soc_camera_apply_sensor_flags(struct soc_camera_link *icl,
+                                            unsigned long flags)
+{
+        unsigned long f;
+
+        /* If only one of the two polarities is supported, switch to the opposite */
+        if (icl->flags & SOCAM_SENSOR_INVERT_HSYNC) {
+                f = flags & (SOCAM_HSYNC_ACTIVE_HIGH | SOCAM_HSYNC_ACTIVE_LOW);
+                if (f == SOCAM_HSYNC_ACTIVE_HIGH || f == SOCAM_HSYNC_ACTIVE_LOW)
+                        flags ^= SOCAM_HSYNC_ACTIVE_HIGH | SOCAM_HSYNC_ACTIVE_LOW;
+        }
+
+        if (icl->flags & SOCAM_SENSOR_INVERT_VSYNC) {
+                f = flags & (SOCAM_VSYNC_ACTIVE_HIGH | SOCAM_VSYNC_ACTIVE_LOW);
+                if (f == SOCAM_VSYNC_ACTIVE_HIGH || f == SOCAM_VSYNC_ACTIVE_LOW)
+                        flags ^= SOCAM_VSYNC_ACTIVE_HIGH | SOCAM_VSYNC_ACTIVE_LOW;
+        }
+
+        if (icl->flags & SOCAM_SENSOR_INVERT_PCLK) {
+                f = flags & (SOCAM_PCLK_SAMPLE_RISING | SOCAM_PCLK_SAMPLE_FALLING);
+                if (f == SOCAM_PCLK_SAMPLE_RISING || f == SOCAM_PCLK_SAMPLE_FALLING)
+                        flags ^= SOCAM_PCLK_SAMPLE_RISING | SOCAM_PCLK_SAMPLE_FALLING;
+        }
+
+        return flags;
+}
+EXPORT_SYMBOL(soc_camera_apply_sensor_flags);
+
 static int soc_camera_try_fmt_vid_cap(struct file *file, void *priv,
                                       struct v4l2_format *f)
 {