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usb: dwc2: hcd_queue: Fix use of floating point literal
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commit 310780e 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/usb/dwc2/hcd_queue.c:1744:25: error: expression requires  'long double' type support, but target 'x86_64-unknown-linux-gnu' does not support it
                         delay = ktime_set(0, DWC2_RETRY_WAIT_DELAY);
                                             ^
 drivers/usb/dwc2/hcd_queue.c:62:34: note: expanded from macro 'DWC2_RETRY_WAIT_DELAY'
 #define DWC2_RETRY_WAIT_DELAY (1 * 1E6L)
                                 ^
 1 error 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 a floating point value in this driver, as
the value is only used as a parameter to a function that expects an
integer type. Use NSEC_PER_MSEC, which is the same integer value as
'1E6L', to avoid changing functionality but fix the error.

Link: ClangBuiltLinux#1497
Link: llvm/llvm-project@a8083d4
Fixes: 6ed30a7 ("usb: dwc2: host: use hrtimer for NAK retries")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: John Keeping <john@metanate.com>
Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20211105145802.2520658-1-nathan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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nathanchance authored and Sasha Levin committed Nov 28, 2021
1 parent b1186f0 commit becc246
Showing 1 changed file with 1 addition and 1 deletion.
2 changes: 1 addition & 1 deletion drivers/usb/dwc2/hcd_queue.c
Original file line number Diff line number Diff line change
Expand Up @@ -59,7 +59,7 @@
#define DWC2_UNRESERVE_DELAY (msecs_to_jiffies(5))

/* If we get a NAK, wait this long before retrying */
#define DWC2_RETRY_WAIT_DELAY 1*1E6L
#define DWC2_RETRY_WAIT_DELAY (1 * NSEC_PER_MSEC)

/**
* dwc2_periodic_channel_available() - Checks that a channel is available for a
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