[PATCH v1 4/7] i2c: nomadik: Use HZ_PER_GHZ constant instead of plain number

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

Use defined constant to avoid the possible mistakes and to provide
an additional information on the units.

While at it, drop unneeded 64-bit division, all operands fit 32-bit.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/busses/i2c-nomadik.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index 19b648fc094d..b63ee51c1652 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -31,6 +31,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>
+#include <linux/units.h>
 
 #define DRIVER_NAME "nmk-i2c"
 
@@ -419,10 +420,10 @@ static void setup_i2c_controller(struct nmk_i2c_dev *priv)
 	 * modes are 250ns, 100ns, 10ns respectively.
 	 *
 	 * As the time for one cycle T in nanoseconds is
-	 * T = (1/f) * 1000000000 =>
-	 * slsu = cycles / (1000000000 / f) + 1
+	 * T = (1/f) * HZ_PER_GHZ =>
+	 * slsu = cycles / (HZ_PER_GHZ / f) + 1
 	 */
-	ns = DIV_ROUND_UP_ULL(1000000000ULL, i2c_clk);
+	ns = DIV_ROUND_UP(HZ_PER_GHZ, i2c_clk);
 	switch (priv->sm) {
 	case I2C_FREQ_MODE_FAST:
 	case I2C_FREQ_MODE_FAST_PLUS:
-- 
2.50.1