media: atomisp: Make bds_factors_list be type of struct u32_fract

The list contains the Bayer scale index, and rational fraction of it.
The struct u32_fract is suitable type to hold that. Convert the driver
to use latter instead of former.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/staging/media/atomisp/pci/camera/pipe/interface/ia_css_pipe_binarydesc.h

@@ -16,6 +16,8 @@
 #ifndef __IA_CSS_PIPE_BINARYDESC_H__
 #define __IA_CSS_PIPE_BINARYDESC_H__
 
+#include <linux/math.h>
+
 #include <ia_css_types.h>		/* ia_css_pipe */
 #include <ia_css_frame_public.h>	/* ia_css_frame_info */
 #include <ia_css_binary.h>		/* ia_css_binary_descr */
@@ -56,17 +58,12 @@ void ia_css_pipe_get_vfpp_binarydesc(
  *
  * @param[in] bds_factor: The bayer downscaling factor.
  *		(= The bds_factor member in the sh_css_bds_factor structure.)
- * @param[out] bds_factor_numerator: The numerator of the bayer downscaling factor.
- *		(= The numerator member in the sh_css_bds_factor structure.)
- * @param[out] bds_factor_denominator: The denominator of the bayer downscaling factor.
- *		(= The denominator member in the sh_css_bds_factor structure.)
+ * @param[out] bds: The rational fraction of the bayer downscaling factor.
+ *		(= The respective member in the sh_css_bds_factor structure.)
  * @return	0 or error code upon error.
  *
  */
-int sh_css_bds_factor_get_numerator_denominator(
-    unsigned int bds_factor,
-    unsigned int *bds_factor_numerator,
-    unsigned int *bds_factor_denominator);
+int sh_css_bds_factor_get_fract(unsigned int bds_factor, struct u32_fract *bds);
 
 /* @brief Get a binary descriptor for preview stage.
  *

drivers/staging/media/atomisp/pci/camera/pipe/src/pipe_binarydesc.c

@@ -13,6 +13,9 @@
  * more details.
  */
 
+#include <linux/kernel.h>
+#include <linux/math.h>
+
 #include "ia_css_pipe_binarydesc.h"
 #include "ia_css_frame_format.h"
 #include "ia_css_pipe.h"
@@ -23,7 +26,6 @@
 #include <assert_support.h>
 /* HRT_GDC_N */
 #include "gdc_device.h"
-#include <linux/kernel.h>
 
 /* This module provides a binary descriptions to used to find a binary. Since,
  * every stage is associated with a binary, it implicity helps stage
@@ -126,40 +128,29 @@ void ia_css_pipe_get_vfpp_binarydesc(
 	IA_CSS_LEAVE_PRIVATE("");
 }
 
-static struct sh_css_bds_factor bds_factors_list[] = {
-	{1, 1, SH_CSS_BDS_FACTOR_1_00},
-	{5, 4, SH_CSS_BDS_FACTOR_1_25},
-	{3, 2, SH_CSS_BDS_FACTOR_1_50},
-	{2, 1, SH_CSS_BDS_FACTOR_2_00},
-	{9, 4, SH_CSS_BDS_FACTOR_2_25},
-	{5, 2, SH_CSS_BDS_FACTOR_2_50},
-	{3, 1, SH_CSS_BDS_FACTOR_3_00},
-	{4, 1, SH_CSS_BDS_FACTOR_4_00},
-	{9, 2, SH_CSS_BDS_FACTOR_4_50},
-	{5, 1, SH_CSS_BDS_FACTOR_5_00},
-	{6, 1, SH_CSS_BDS_FACTOR_6_00},
-	{8, 1, SH_CSS_BDS_FACTOR_8_00}
+static struct u32_fract bds_factors_list[] = {
+	[SH_CSS_BDS_FACTOR_1_00] = {1, 1},
+	[SH_CSS_BDS_FACTOR_1_25] = {5, 4},
+	[SH_CSS_BDS_FACTOR_1_50] = {3, 2},
+	[SH_CSS_BDS_FACTOR_2_00] = {2, 1},
+	[SH_CSS_BDS_FACTOR_2_25] = {9, 4},
+	[SH_CSS_BDS_FACTOR_2_50] = {5, 2},
+	[SH_CSS_BDS_FACTOR_3_00] = {3, 1},
+	[SH_CSS_BDS_FACTOR_4_00] = {4, 1},
+	[SH_CSS_BDS_FACTOR_4_50] = {9, 2},
+	[SH_CSS_BDS_FACTOR_5_00] = {5, 1},
+	[SH_CSS_BDS_FACTOR_6_00] = {6, 1},
+	[SH_CSS_BDS_FACTOR_8_00] = {8, 1},
 };
 
-int sh_css_bds_factor_get_numerator_denominator(
-    unsigned int bds_factor,
-    unsigned int *bds_factor_numerator,
-    unsigned int *bds_factor_denominator)
+int sh_css_bds_factor_get_fract(unsigned int bds_factor, struct u32_fract *bds)
 {
-	unsigned int i;
-
-	/* Loop over all bds factors until a match is found */
-	for (i = 0; i < ARRAY_SIZE(bds_factors_list); i++) {
-		if (bds_factors_list[i].bds_factor == bds_factor) {
-			*bds_factor_numerator = bds_factors_list[i].numerator;
-			*bds_factor_denominator = bds_factors_list[i].denominator;
-			return 0;
-		}
-	}
+	/* Throw an error since bds_factor cannot be found in bds_factors_list */
+	if (bds_factor >= ARRAY_SIZE(bds_factors_list))
+		return -EINVAL;
 
-	/* Throw an error since bds_factor cannot be found
-	in bds_factors_list */
-	return -EINVAL;
+	*bds = bds_factors_list[bds_factor];
+	return 0;
 }
 
 int binarydesc_calculate_bds_factor(
@@ -194,7 +185,7 @@ int binarydesc_calculate_bds_factor(
 			    (out_h * num / den <= in_h);
 
 		if (cond) {
-			*bds_factor = bds_factors_list[i].bds_factor;
+			*bds_factor = i;
 			return 0;
 		}
 	}

drivers/staging/media/atomisp/pci/runtime/binary/src/binary.c

@@ -13,6 +13,8 @@
  * more details.
  */
 
+#include <linux/math.h>
+
 #include <math_support.h>
 #include <gdc_device.h>	/* HR_GDC_N */
 
@@ -128,16 +130,8 @@ ia_css_binary_compute_shading_table_bayer_origin(
 {
 	int err;
 
-	/* Numerator and denominator of the fixed bayer downscaling factor.
-	(numerator >= denominator) */
-	unsigned int bds_num, bds_den;
-
-	/* Horizontal/Vertical ratio of bayer scaling
-	between input area and output area. */
-	unsigned int bs_hor_ratio_in;
-	unsigned int bs_hor_ratio_out;
-	unsigned int bs_ver_ratio_in;
-	unsigned int bs_ver_ratio_out;
+	/* Rational fraction of the fixed bayer downscaling factor. */
+	struct u32_fract bds;
 
 	/* Left padding set by InputFormatter. */
 	unsigned int left_padding_bqs;			/* in bqs */
@@ -158,19 +152,11 @@ ia_css_binary_compute_shading_table_bayer_origin(
 	unsigned int bad_bqs_on_top_before_bs;	/* in bqs */
 	unsigned int bad_bqs_on_top_after_bs;	/* in bqs */
 
-	/* Get the numerator and denominator of bayer downscaling factor. */
-	err = sh_css_bds_factor_get_numerator_denominator
-	(required_bds_factor, &bds_num, &bds_den);
+	/* Get the rational fraction of bayer downscaling factor. */
+	err = sh_css_bds_factor_get_fract(required_bds_factor, &bds);
 	if (err)
 		return err;
 
-	/* Set the horizontal/vertical ratio of bayer scaling
-	between input area and output area. */
-	bs_hor_ratio_in  = bds_num;
-	bs_hor_ratio_out = bds_den;
-	bs_ver_ratio_in  = bds_num;
-	bs_ver_ratio_out = bds_den;
-
 	/* Set the left padding set by InputFormatter. (ifmtr.c) */
 	if (stream_config->left_padding == -1)
 		left_padding_bqs = _ISP_BQS(binary->left_padding);
@@ -228,18 +214,18 @@ ia_css_binary_compute_shading_table_bayer_origin(
 	located on the shading table during the shading correction. */
 	res->sc_bayer_origin_x_bqs_on_shading_table =
 		((left_padding_adjusted_bqs + bad_bqs_on_left_before_bs)
-		* bs_hor_ratio_out + bs_hor_ratio_in / 2) / bs_hor_ratio_in
+		* bds.denominator + bds.numerator / 2) / bds.numerator
 		+ bad_bqs_on_left_after_bs;
-	/* "+ bs_hor_ratio_in/2": rounding for division by bs_hor_ratio_in */
+	/* "+ bds.numerator / 2": rounding for division by bds.numerator */
 	res->sc_bayer_origin_y_bqs_on_shading_table =
-		(bad_bqs_on_top_before_bs * bs_ver_ratio_out + bs_ver_ratio_in / 2) / bs_ver_ratio_in
+		(bad_bqs_on_top_before_bs * bds.denominator + bds.numerator / 2) / bds.numerator
 		+ bad_bqs_on_top_after_bs;
-	/* "+ bs_ver_ratio_in/2": rounding for division by bs_ver_ratio_in */
+	/* "+ bds.numerator / 2": rounding for division by bds.numerator */
 
-	res->bayer_scale_hor_ratio_in  = (uint32_t)bs_hor_ratio_in;
-	res->bayer_scale_hor_ratio_out = (uint32_t)bs_hor_ratio_out;
-	res->bayer_scale_ver_ratio_in  = (uint32_t)bs_ver_ratio_in;
-	res->bayer_scale_ver_ratio_out = (uint32_t)bs_ver_ratio_out;
+	res->bayer_scale_hor_ratio_in  = bds.numerator;
+	res->bayer_scale_hor_ratio_out = bds.denominator;
+	res->bayer_scale_ver_ratio_in  = bds.numerator;
+	res->bayer_scale_ver_ratio_out = bds.denominator;
 
 	return err;
 }

drivers/staging/media/atomisp/pci/sh_css_param_shading.c

@@ -13,6 +13,7 @@
  * more details.
  */
 
+#include <linux/math.h>
 #include <linux/slab.h>
 
 #include <math_support.h>
@@ -239,10 +240,9 @@ prepare_shading_table(const struct ia_css_shading_table *in_table,
 {
 	unsigned int input_width, input_height, table_width, table_height, i;
 	unsigned int left_padding, top_padding, left_cropping;
-	unsigned int bds_numerator, bds_denominator;
-	int right_padding;
-
 	struct ia_css_shading_table *result;
+	struct u32_fract bds;
+	int right_padding;
 
 	assert(target_table);
 	assert(binary);
@@ -265,17 +265,16 @@ prepare_shading_table(const struct ia_css_shading_table *in_table,
 	left_cropping = (binary->info->sp.pipeline.left_cropping == 0) ?
 			binary->dvs_envelope.width : 2 * ISP_VEC_NELEMS;
 
-	sh_css_bds_factor_get_numerator_denominator
-	(bds_factor, &bds_numerator, &bds_denominator);
+	sh_css_bds_factor_get_fract(bds_factor, &bds);
 
 	left_padding  = (left_padding + binary->info->sp.pipeline.left_cropping) *
-			bds_numerator / bds_denominator -
+			bds.numerator / bds.denominator -
 			binary->info->sp.pipeline.left_cropping;
 	right_padding = (binary->internal_frame_info.res.width -
-			 binary->effective_in_frame_res.width * bds_denominator /
-			 bds_numerator - left_cropping) * bds_numerator / bds_denominator;
-	top_padding = binary->info->sp.pipeline.top_cropping * bds_numerator /
-		      bds_denominator -
+			 binary->effective_in_frame_res.width * bds.denominator /
+			 bds.numerator - left_cropping) * bds.numerator / bds.denominator;
+	top_padding = binary->info->sp.pipeline.top_cropping * bds.numerator /
+		      bds.denominator -
 		      binary->info->sp.pipeline.top_cropping;
 
 	/*