bcm27xx: add support for linux v5.15

Build system: x86_64
Build-tested: bcm2708, bcm2709, bcm2710, bcm2711
Run-tested: bcm2708/RPiB+, bcm2709/RPi3B, bcm2710/RPi3B, bcm2711/RPi4B

Signed-off-by: Marty Jones <mj8263788@gmail.com>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/target/linux/bcm27xx/patches-5.15/950-0833-clk-Use-clamp-instead-of-open-coding-our-own.patch b/target/linux/bcm27xx/patches-5.15/950-0833-clk-Use-clamp-instead-of-open-coding-our-own.patch
new file mode 100644
index 0000000000..02a0a12401
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.15/950-0833-clk-Use-clamp-instead-of-open-coding-our-own.patch
@@ -0,0 +1,33 @@
+From dbd88e6fdd547cf8f6765b8dade9f89cf5c0ead9 Mon Sep 17 00:00:00 2001
+From: Maxime Ripard <maxime@cerno.tech>
+Date: Mon, 17 Jan 2022 16:38:10 +0100
+Subject: [PATCH] clk: Use clamp instead of open-coding our own
+
+The code in clk_set_rate_range() will, if the current rate is outside of
+the new range, force it to the minimum or maximum.
+
+Since it's running under the condition that the rate is either lower
+than the minimum, or higher than the maximum, this is equivalent to
+using clamp, while being less readable. Let's switch to using clamp
+instead.
+
+Signed-off-by: Maxime Ripard <maxime@cerno.tech>
+---
+ drivers/clk/clk.c | 6 +-----
+ 1 file changed, 1 insertion(+), 5 deletions(-)
+
+--- a/drivers/clk/clk.c
++++ b/drivers/clk/clk.c
+@@ -2387,11 +2387,7 @@ int clk_set_rate_range(struct clk *clk,
+ 		 *   this corner case when determining the rate
+ 		 */
+ 
+-		if (rate < min)
+-			rate = min;
+-		else
+-			rate = max;
+-
++		rate = clamp(clk->core->req_rate, min, max);
+ 		ret = clk_core_set_rate_nolock(clk->core, rate);
+ 		if (ret) {
+ 			/* rollback the changes */