Merge tag 'staging-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging and IIO driver updates from Greg KH:
 "Here is the "big" set of staging and IIO driver patches for 5.12-rc1.

  Nothing really huge in here, the number of staging tree patches has
  gone down for a bit, maybe there's only so much churn to happen in
  here at the moment.

  The IIO changes are:

   - new drivers

   - new DT bindings

   - new iio driver features

  with full details in the shortlog.

  The staging driver patches are just a lot of tiny coding style
  cleanups, along with some semi-larger hikey driver cleanups as those
  are _almost_ good enough to get out of the staging tree, but will
  probably have to wait until 5.13 to have happen.

  All of these have been in linux-next with no reported issues"

* tag 'staging-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (189 commits)
  staging: hikey9xx: Fix alignment of function parameters
  staging: greybus: Fixed a misspelling in hid.c
  staging: wimax/i2400m: fix some byte order issues found by sparse
  staging: wimax: i2400m: fix some incorrect type warnings
  staging: greybus: minor code style fix
  staging:wlan-ng: use memdup_user instead of kmalloc/copy_from_user
  staging:r8188eu: use IEEE80211_FCTL_* kernel definitions
  staging: rtl8192e: remove multiple blank lines
  staging: greybus: Fixed alignment issue in hid.c
  staging: wfx: remove unused included header files
  staging: nvec: minor coding style fix
  staging: wimax: Fix some coding style problem
  staging: fbtft: add tearing signal detect
  staging: vt6656: Fixed issue with alignment in rf.c
  staging: qlge: Remove duplicate word in comment
  staging: rtl8723bs: remove obsolete commented out code
  staging: rtl8723bs: fix function comments to follow kernel-doc
  staging: wfx: avoid defining array of flexible struct
  staging: rtl8723bs: Replace one-element array with flexible-array member in struct ndis_80211_var_ie
  staging: Replace lkml.org links with lore
  ...

1 files changed, 19 insertions, 0 deletions

diff --git a/include/linux/fixp-arith.h b/include/linux/fixp-arith.h
index 8396013785ef..281cb4f83dbe 100644
--- a/include/linux/fixp-arith.h
+++ b/include/linux/fixp-arith.h
@@ -141,4 +141,23 @@ static inline s32 fixp_sin32_rad(u32 radians, u32 twopi)
 #define fixp_cos32_rad(rad, twopi)	\
 	fixp_sin32_rad(rad + twopi / 4, twopi)
 
+/**
+ * fixp_linear_interpolate() - interpolates a value from two known points
+ *
+ * @x0: x value of point 0
+ * @y0: y value of point 0
+ * @x1: x value of point 1
+ * @y1: y value of point 1
+ * @x: the linear interpolant
+ */
+static inline int fixp_linear_interpolate(int x0, int y0, int x1, int y1, int x)
+{
+	if (y0 == y1 || x == x0)
+		return y0;
+	if (x1 == x0 || x == x1)
+		return y1;
+
+	return y0 + ((y1 - y0) * (x - x0) / (x1 - x0));
+}
+
 #endif