drivers: video: introduce video_bits_per_pixel(pixelformat) helper

This was present in the form of video_pix_fmt_bpp() inside ST and NXP
drivers, and was returning the number of bytes, which does not allow
support for 10-bits, 4-bits or non-byte aligned video formats.
The helper leverages the VIDEO_PIX_FMT_*_BITS macros.

Signed-off-by: Josuah Demangeon <me@josuah.net>

drivers/video/video_mcux_csi.c

@@ -123,7 +123,7 @@ static inline void video_pix_fmt_convert(struct video_format *fmt, bool isGetFmt
 		break;
 	}
 
-	fmt->pitch = fmt->width * video_pix_fmt_bpp(fmt->pixelformat);
+	fmt->pitch = fmt->width * video_bits_per_pixel(fmt->pixelformat) / BITS_PER_BYTE;
 }
 #endif
 
@@ -132,7 +132,7 @@ static int video_mcux_csi_set_fmt(const struct device *dev, enum video_endpoint_
 {
 	const struct video_mcux_csi_config *config = dev->config;
 	struct video_mcux_csi_data *data = dev->data;
-	unsigned int bpp = video_pix_fmt_bpp(fmt->pixelformat);
+	unsigned int bpp = video_bits_per_pixel(fmt->pixelformat) / BITS_PER_BYTE;
 	status_t ret;
 	struct video_format format = *fmt;
 

drivers/video/video_mcux_mipi_csi2rx.c

@@ -73,8 +73,8 @@ static int mipi_csi2rx_update_settings(const struct device *dev, enum video_endp
 		return -ENOTSUP;
 	}
 
-	bpp = video_pix_fmt_bpp(fmt.pixelformat) * 8;
-	sensor_byte_clk = sensor_pixel_rate * bpp / drv_data->csi2rxConfig.laneNum / 8;
+	bpp = video_bits_per_pixel(fmt.pixelformat);
+	sensor_byte_clk = sensor_pixel_rate * bpp / drv_data->csi2rxConfig.laneNum / BITS_PER_BYTE;
 
 	ret = clock_control_get_rate(drv_data->clock_dev, drv_data->clock_root, &root_clk_rate);
 	if (ret) {
@@ -224,7 +224,7 @@ static int mipi_csi2rx_get_frmival(const struct device *dev, enum video_endpoint
 
 static uint64_t mipi_csi2rx_cal_frame_size(const struct video_format *fmt)
 {
-	return fmt->height * fmt->width * video_pix_fmt_bpp(fmt->pixelformat) * 8;
+	return fmt->height * fmt->width * video_bits_per_pixel(fmt->pixelformat);
 }
 
 static uint64_t mipi_csi2rx_estimate_pixel_rate(const struct video_frmival *cur_fmival,

drivers/video/video_stm32_dcmi.c

@@ -198,7 +198,7 @@ static int video_stm32_dcmi_set_fmt(const struct device *dev,
 {
 	const struct video_stm32_dcmi_config *config = dev->config;
 	struct video_stm32_dcmi_data *data = dev->data;
-	unsigned int bpp = video_pix_fmt_bpp(fmt->pixelformat);
+	unsigned int bpp = video_bits_per_pixel(fmt->pixelformat) / BITS_PER_BYTE;
 
 	if (bpp == 0 || (ep != VIDEO_EP_OUT && ep != VIDEO_EP_ALL)) {
 		return -EINVAL;

include/zephyr/drivers/video.h

@@ -812,6 +812,14 @@ void video_closest_frmival_stepwise(const struct video_frmival_stepwise *stepwis
 void video_closest_frmival(const struct device *dev, enum video_endpoint_id ep,
 			   struct video_frmival_enum *match);
 
+/**
+ * @defgroup video_pixel_formats Video pixel formats
+ * The @c | characters separate the pixels, and spaces separate the bytes.
+ * The uppercase letter represents the most significant bit.
+ * The lowercase letters represent the rest of the bits.
+ * @{
+ */
+
 /**
  * @brief Four-character-code uniquely identifying the pixel format
  */
@@ -829,14 +837,6 @@ void video_closest_frmival(const struct device *dev, enum video_endpoint_id ep,
  */
 #define VIDEO_FOURCC_FROM_STR(str) VIDEO_FOURCC((str)[0], (str)[1], (str)[2], (str)[3])
 
-/**
- * @defgroup video_pixel_formats Video pixel formats
- * The @c | characters separate the pixels, and spaces separate the bytes.
- * The uppercase letter represents the most significant bit.
- * The lowercase letters represent the rest of the bits.
- * @{
- */
-
 /**
  * @name Bayer formats (R, G, B channels).
  *
@@ -966,33 +966,37 @@ void video_closest_frmival(const struct device *dev, enum video_endpoint_id ep,
  */
 
 /**
- * @}
- */
-
-/**
- * @brief Get number of bytes per pixel of a pixel format
+ * @brief Get number of bits per pixel of a pixel format
+ *
+ * @param pixfmt FourCC pixel format value (@ref video_pixel_formats).
  *
- * @param pixfmt FourCC pixel format value (\ref video_pixel_formats).
+ * @retval 0 if the format is unhandled or if it is variable number of bits
+ * @retval bit size of one pixel for this format
  */
-static inline unsigned int video_pix_fmt_bpp(uint32_t pixfmt)
+static inline unsigned int video_bits_per_pixel(uint32_t pixfmt)
 {
 	switch (pixfmt) {
 	case VIDEO_PIX_FMT_BGGR8:
 	case VIDEO_PIX_FMT_GBRG8:
 	case VIDEO_PIX_FMT_GRBG8:
 	case VIDEO_PIX_FMT_RGGB8:
-		return 1;
+		return 8;
 	case VIDEO_PIX_FMT_RGB565:
 	case VIDEO_PIX_FMT_YUYV:
-		return 2;
+		return 16;
 	case VIDEO_PIX_FMT_XRGB32:
 	case VIDEO_PIX_FMT_XYUV32:
-		return 4;
+		return 32;
 	default:
+		/* Variable number of bits per pixel or unknown format */
 		return 0;
 	}
 }
 
+/**
+ * @}
+ */
+
 #ifdef __cplusplus
 }
 #endif