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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-02-20 12:23:17 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-02-20 12:23:17 +0300
commit59142f808a5e8722e66ab1753532ed5d300a34dd (patch)
treec8c613f06b54dceca67f4ebe0719910de0f4be24 /lib
parent54ef5b9db76767e91f77b0588245e6e87d891548 (diff)
parentd6ad805844c52d256c2a3ff3d60daa10d27a8b64 (diff)
downloadlinux-59142f808a5e8722e66ab1753532ed5d300a34dd.tar.xz
Merge tag 'iio-for-4.17a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes: First round of new devices, features and cleanups for IIO in the 4.17 cycle. Outside of IIO * Strongly typed 64bit int_sqrt function needed by the mlx90632 New device support * adc081s - New driver supporting adc081s, adc101s and adc121s TI ADCs. * ad5272 - New driver supproting the ad5272 and ad5274 ADI digital potentiometers with DT bindings. * axp20x_adc - support the AXP813 ADC - includes rework patches to prepare for this. * mlx90632 - New driver with dt bindings for this IR temperature sensor. Features * axp20x_adc - Add DT bindings and probing. * dht11 - The sensor has a wider range than advertised in the datasheet - support it. * st_lsm6dsx - Add hardware timestamp su9pport. Cleanups * ABI docs - Update email contact for Matt Ranostay * SPDX changes - Matt Ranostay has moved his drivers over to SPDX. Currently we are making this an author choice in IIO. * ad7192 - Disable burnout current on misconfiguration. No actually effect as they simply won't work otherwise. * ad7476 - Drop a license definition that was replicating information in SPDX tag. * ade7758 - Expand buf_lock to cover both buffer and state protection allowing unintented uses of mlock in the core to be removed. * ade7759 - Align parameters to opening parenthesis. * at91_adc - Depend on sysfs instead of selecting it - for try wide consistency. * ccs811 - trivial naming type for a define. * ep93xx - Drop a redundant return as a result checking platform_get_resource. * hts221 - Regmap conversion which simplifies the driver somewhat. - Clean up some restricted endian cast warnings. - Drop a trailing whitespace from a comment - Drop an unnecessary get_unaligned by changing to the right 16bit data type. * ms5611 - Fix coding style in the probe function (whitespace) * st_accel - Use strlcpy instead of strncpy to avoid potentially truncating a string.
Diffstat (limited to 'lib')
-rw-r--r--lib/int_sqrt.c30
1 files changed, 30 insertions, 0 deletions
diff --git a/lib/int_sqrt.c b/lib/int_sqrt.c
index e2d329099bf7..14436f4ca6bd 100644
--- a/lib/int_sqrt.c
+++ b/lib/int_sqrt.c
@@ -38,3 +38,33 @@ unsigned long int_sqrt(unsigned long x)
return y;
}
EXPORT_SYMBOL(int_sqrt);
+
+#if BITS_PER_LONG < 64
+/**
+ * int_sqrt64 - strongly typed int_sqrt function when minimum 64 bit input
+ * is expected.
+ * @x: 64bit integer of which to calculate the sqrt
+ */
+u32 int_sqrt64(u64 x)
+{
+ u64 b, m, y = 0;
+
+ if (x <= ULONG_MAX)
+ return int_sqrt((unsigned long) x);
+
+ m = 1ULL << (fls64(x) & ~1ULL);
+ while (m != 0) {
+ b = y + m;
+ y >>= 1;
+
+ if (x >= b) {
+ x -= b;
+ y += m;
+ }
+ m >>= 2;
+ }
+
+ return y;
+}
+EXPORT_SYMBOL(int_sqrt64);
+#endif