V4L/DVB (7336): soc-camera: streamline hardware parameter negotiation

Improve hardware parameter negotiation between the camera host driver and
camera drivers. Parameters like horizontal and vertical synchronisation,
pixel clock polarity shall be set depending on capabilities of the
parties.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/mt9m001.c b/drivers/media/video/mt9m001.c
index 4ad8343..acb5454 100644
--- a/drivers/media/video/mt9m001.c
+++ b/drivers/media/video/mt9m001.c
@@ -210,40 +210,64 @@
 #endif
 }
 
-static int mt9m001_set_capture_format(struct soc_camera_device *icd,
-		__u32 pixfmt, struct v4l2_rect *rect, unsigned int flags)
+static int bus_switch_possible(struct mt9m001 *mt9m001)
+{
+#ifdef CONFIG_MT9M001_PCA9536_SWITCH
+	return gpio_is_valid(mt9m001->switch_gpio);
+#else
+	return 0;
+#endif
+}
+
+static int mt9m001_set_bus_param(struct soc_camera_device *icd,
+				 unsigned long flags)
 {
 	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
-	unsigned int width_flag = flags & (IS_DATAWIDTH_10 | IS_DATAWIDTH_9 |
-					   IS_DATAWIDTH_8);
+	unsigned int width_flag = flags & SOCAM_DATAWIDTH_MASK;
 	int ret;
-	const u16 hblank = 9, vblank = 25;
 
-	/* MT9M001 has all capture_format parameters fixed */
-	if (!(flags & IS_MASTER) ||
-	    !(flags & IS_PCLK_SAMPLE_RISING) ||
-	    !(flags & IS_HSYNC_ACTIVE_HIGH) ||
-	    !(flags & IS_VSYNC_ACTIVE_HIGH))
-		return -EINVAL;
+	/* Flags validity verified in test_bus_param */
 
-	/* Only one width bit may be set */
-	if (!is_power_of_2(width_flag))
-		return -EINVAL;
-
-	if ((mt9m001->datawidth != 10 && (width_flag == IS_DATAWIDTH_10)) ||
-	    (mt9m001->datawidth != 9  && (width_flag == IS_DATAWIDTH_9)) ||
-	    (mt9m001->datawidth != 8  && (width_flag == IS_DATAWIDTH_8))) {
+	if ((mt9m001->datawidth != 10 && (width_flag == SOCAM_DATAWIDTH_10)) ||
+	    (mt9m001->datawidth != 9  && (width_flag == SOCAM_DATAWIDTH_9)) ||
+	    (mt9m001->datawidth != 8  && (width_flag == SOCAM_DATAWIDTH_8))) {
 		/* Well, we actually only can do 10 or 8 bits... */
-		if (width_flag == IS_DATAWIDTH_9)
+		if (width_flag == SOCAM_DATAWIDTH_9)
 			return -EINVAL;
 		ret = bus_switch_act(mt9m001,
-				     width_flag == IS_DATAWIDTH_8);
+				     width_flag == SOCAM_DATAWIDTH_8);
 		if (ret < 0)
 			return ret;
 
-		mt9m001->datawidth = width_flag == IS_DATAWIDTH_8 ? 8 : 10;
+		mt9m001->datawidth = width_flag == SOCAM_DATAWIDTH_8 ? 8 : 10;
 	}
 
+	return 0;
+}
+
+static unsigned long mt9m001_query_bus_param(struct soc_camera_device *icd)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+	unsigned int width_flag = SOCAM_DATAWIDTH_10;
+
+	if (bus_switch_possible(mt9m001))
+		width_flag |= SOCAM_DATAWIDTH_8;
+
+	/* MT9M001 has all capture_format parameters fixed */
+	return SOCAM_PCLK_SAMPLE_RISING |
+		SOCAM_HSYNC_ACTIVE_HIGH |
+		SOCAM_VSYNC_ACTIVE_HIGH |
+		SOCAM_MASTER |
+		width_flag;
+}
+
+static int mt9m001_set_fmt_cap(struct soc_camera_device *icd,
+		__u32 pixfmt, struct v4l2_rect *rect)
+{
+	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
+	int ret;
+	const u16 hblank = 9, vblank = 25;
+
 	/* Blanking and start values - default... */
 	ret = reg_write(icd, MT9M001_HORIZONTAL_BLANKING, hblank);
 	if (ret >= 0)
@@ -348,12 +372,6 @@
 }
 #endif
 
-static unsigned int mt9m001_get_datawidth(struct soc_camera_device *icd)
-{
-	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
-	return mt9m001->datawidth;
-}
-
 const struct v4l2_queryctrl mt9m001_controls[] = {
 	{
 		.id		= V4L2_CID_VFLIP,
@@ -401,11 +419,12 @@
 	.release		= mt9m001_release,
 	.start_capture		= mt9m001_start_capture,
 	.stop_capture		= mt9m001_stop_capture,
-	.set_capture_format	= mt9m001_set_capture_format,
+	.set_fmt_cap		= mt9m001_set_fmt_cap,
 	.try_fmt_cap		= mt9m001_try_fmt_cap,
+	.set_bus_param		= mt9m001_set_bus_param,
+	.query_bus_param	= mt9m001_query_bus_param,
 	.formats		= NULL, /* Filled in later depending on the */
 	.num_formats		= 0,	/* camera type and data widths */
-	.get_datawidth		= mt9m001_get_datawidth,
 	.controls		= mt9m001_controls,
 	.num_controls		= ARRAY_SIZE(mt9m001_controls),
 	.get_control		= mt9m001_get_control,