FAILED: patch "[PATCH] power: reset: ltc2952: Fix use of floating point literals" failed to apply to 4.9-stable tree

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 644106cdb89844be2496b21175b7c0c2e0fab381 Mon Sep 17 00:00:00 2001
From: Nathan Chancellor <[email protected]>
Date: Fri, 5 Nov 2021 08:20:50 -0700
Subject: [PATCH] power: reset: ltc2952: Fix use of floating point literals

A new commit in LLVM causes an error on the use of 'long double' when '-mno-x87' is used, which the kernel does through an alias, '-mno-80387' (see the LLVM commit below for more details around why it does this).

drivers/power/reset/ltc2952-poweroff.c:162:28: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it

        data->wde_interval = 300L * 1E6L;
                                  ^
drivers/power/reset/ltc2952-poweroff.c:162:21: error: expression requires  'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it
        data->wde_interval = 300L * 1E6L;
                           ^
drivers/power/reset/ltc2952-poweroff.c:163:41: error: expression requires  'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it
        data->trigger_delay = ktime_set(2, 500L*1E6L);
                                               ^

3 errors generated.

This happens due to the use of a 'long double' literal. The 'E6' part of '1E6L' causes the literal to be a 'double' then the 'L' suffix promotes it to 'long double'.

There is no visible reason for floating point values in this driver, as the values are only assigned to integer types. Use NSEC_PER_MSEC, which is the same integer value as '1E6L', to avoid changing functionality but fix the error.

index fbb344353fe4..65d9528cc989 100644
@@ -159,8 +159,8 @@ static void ltc2952_poweroff_kill(void)
 
 static void ltc2952_poweroff_default(struct ltc2952_poweroff *data)
 {
-	data->wde_interval = 300L * 1E6L;
-	data->trigger_delay = ktime_set(2, 500L*1E6L);
+	data->wde_interval = 300L * NSEC_PER_MSEC;
+	data->trigger_delay = ktime_set(2, 500L * NSEC_PER_MSEC);
 
 	hrtimer_init(&data->timer_trigger, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	data->timer_trigger.function = ltc2952_poweroff_timer_trigger;

commit 644106cdb89844be2496b21175b7c0c2e0fab381 upstream.

A new commit in LLVM causes an error on the use of 'long double' when '-mno-x87' is used, which the kernel does through an alias, '-mno-80387' (see the LLVM commit below for more details around why it does this).

drivers/power/reset/ltc2952-poweroff.c:162:28: error: expression requires 'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it

        data->wde_interval = 300L * 1E6L;
                                  ^
drivers/power/reset/ltc2952-poweroff.c:162:21: error: expression requires  'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it
        data->wde_interval = 300L * 1E6L;
                           ^
drivers/power/reset/ltc2952-poweroff.c:163:41: error: expression requires  'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it
        data->trigger_delay = ktime_set(2, 500L*1E6L);
                                               ^

3 errors generated.

This happens due to the use of a 'long double' literal. The 'E6' part of '1E6L' causes the literal to be a 'double' then the 'L' suffix promotes it to 'long double'.

There is no visible reason for floating point values in this driver, as the values are only assigned to integer types. Use NSEC_PER_MSEC, which is the same integer value as '1E6L', to avoid changing functionality but fix the error.

---
 drivers/power/reset/ltc2952-poweroff.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

index 15fed9d8f871..ec54cff108b3 100644
@@ -169,8 +169,8 @@ static void ltc2952_poweroff_kill(void)
 
 static void ltc2952_poweroff_default(struct ltc2952_poweroff *data)
 {
-	data->wde_interval = ktime_set(0, 300L*1E6L);
-	data->trigger_delay = ktime_set(2, 500L*1E6L);
+	data->wde_interval = ktime_set(0, 300L * NSEC_PER_MSEC);
+	data->trigger_delay = ktime_set(2, 500L * NSEC_PER_MSEC);
 
 	hrtimer_init(&data->timer_trigger, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	data->timer_trigger.function = ltc2952_poweroff_timer_trigger;

base-commit: 710bf39c7aec32641ea63f6593db1df8c3e4a4d7

2.34.1

Now queued up, thanks.

greg k-h