[PATCH v2 4/4] video/edid: Move int_sqrt() out
Andrey Smirnov
andrew.smirnov at gmail.com
Thu Jun 23 22:35:35 PDT 2016
Move int_sqrt() out of drivers/video/edid.c so that it is availible to
other parts of Barebox.
Signedoffby: Andrey Smirnov <andrew.smirnov at gmail.com>

drivers/video/edid.c  29 
include/int_sqrt.h  22 ++++++++++++++++++++++
lib/Makefile  1 +
lib/int_sqrt.c  46 ++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 69 insertions(+), 29 deletions()
create mode 100644 include/int_sqrt.h
create mode 100644 lib/int_sqrt.c
diff git a/drivers/video/edid.c b/drivers/video/edid.c
index e5c32a0..92b59a5 100644
 a/drivers/video/edid.c
+++ b/drivers/video/edid.c
@@ 321,35 +321,6 @@ static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
}
/**
 * int_sqrt  rough approximation to sqrt
 * @x: integer of which to calculate the sqrt
 *
 * A very rough approximation to the sqrt() function.
 */
unsigned long int_sqrt(unsigned long x)
{
 unsigned long b, m, y = 0;

 if (x <= 1)
 return x;

 m = 1UL << (BITS_PER_LONG  2);
 while (m != 0) {
 b = y + m;
 y >>= 1;

 if (x >= b) {
 x = b;
 y += m;
 }
 m >>= 2;
 }

 return y;
}
EXPORT_SYMBOL(int_sqrt);

/**
* fb_get_hfreq  estimate hsync
* @vfreq: vertical refresh rate
* @yres: vertical resolution
diff git a/include/int_sqrt.h b/include/int_sqrt.h
new file mode 100644
index 0000000..55fb4fb
 /dev/null
+++ b/include/int_sqrt.h
@@ 0,0 +1,22 @@
+/*
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __INT_SQRT__
+#define __INT_SQRT__
+
+unsigned long int_sqrt(unsigned long x);
+
+#endif
diff git a/lib/Makefile b/lib/Makefile
index 399d896..92404fd 100644
 a/lib/Makefile
+++ b/lib/Makefile
@@ 58,3 +58,4 @@ obj$(CONFIG_BAREBOX_LOGO) += logo/
objy += reed_solomon/
obj$(CONFIG_RATP) += ratp.o
objy += list_sort.o
+objy += int_sqrt.o
diff git a/lib/int_sqrt.c b/lib/int_sqrt.c
new file mode 100644
index 0000000..30ccafb
 /dev/null
+++ b/lib/int_sqrt.c
@@ 0,0 +1,46 @@
+/*
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <common.h>
+
+/**
+ * int_sqrt  rough approximation to sqrt
+ * @x: integer of which to calculate the sqrt
+ *
+ * A very rough approximation to the sqrt() function.
+ */
+unsigned long int_sqrt(unsigned long x)
+{
+ unsigned long b, m, y = 0;
+
+ if (x <= 1)
+ return x;
+
+ m = 1UL << (BITS_PER_LONG  2);
+ while (m != 0) {
+ b = y + m;
+ y >>= 1;
+
+ if (x >= b) {
+ x = b;
+ y += m;
+ }
+ m >>= 2;
+ }
+
+ return y;
+}
+EXPORT_SYMBOL(int_sqrt);

2.5.5
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