staging: pi433: use div_u64 for 64-bit division

I ran into this link error on an ARM OABI build:

drivers/staging/pi433/rf69.o: In function `rf69_set_frequency':
rf69.c:(.text+0xc9c): undefined reference to `__udivdi3'

No idea why I didn't see it with the default EABI configurations,
but the right solution here seems to be to use div_u64()
to get the external division implementation.

Fixes: 874bcba65f9a ("staging: pi433: New driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/pi433/rf69.c b/drivers/staging/pi433/rf69.c
index 1b094c38f401b07c0a5e52633da19cdd19d9bc19..f83523e3395d9a14b9c005338c5e3dda8a0ddb2d 100644 (file)
--- a/drivers/staging/pi433/rf69.c
+++ b/drivers/staging/pi433/rf69.c
@@ -238,7 +238,7 @@ int rf69_set_frequency(struct spi_device *spi, u32 frequency)
        do_div(f_step, 524288); //  524288 = 2^19
 
        // check input value
-       f_max = f_step * 8388608 / factor;
+       f_max = div_u64(f_step * 8388608, factor);
        if (frequency > f_max)
        {
                dev_dbg(&spi->dev, "setFrequency: illegal input param");