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power: reset: ltc2952: Fix use of floating point literals
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commit 644106c 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.

Fixes: 6647156 ("power: reset: add LTC2952 poweroff driver")
Link: ClangBuiltLinux/linux#1497
Link: llvm/llvm-project@a8083d4
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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nathanchance authored and gregkh committed Jan 11, 2022
1 parent be81667 commit 550acd7
Showing 1 changed file with 2 additions and 2 deletions.
4 changes: 2 additions & 2 deletions drivers/power/reset/ltc2952-poweroff.c
Expand Up @@ -161,8 +161,8 @@ 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;
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