mmc: omap: Use DIV_ROUND_UP instead of open coded

Also uses NSEC_PER_SEC and USEC_PER_SEC instead of hard-coded value.
This makes the intention more clear.

Signed-off-by: Axel Lin <[e-mail]>
Signed-off-by: Ulf Hansson <[e-mail]>
Signed-off-by: Chris Ball <[e-mail]>

drivers/mmc/host/omap.c

···
 	unsigned long tick_ns;
 
 	if (slot != NULL && slot->host->fclk_enabled && slot->fclk_freq > 0) {
-		tick_ns = (1000000000 + slot->fclk_freq - 1) / slot->fclk_freq;
+		tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
 		ndelay(8 * tick_ns);
 	}
 }
···
 	struct mmc_data *data = host->stop_data;
 	unsigned long tick_ns;
 
-	tick_ns = (1000000000 + slot->fclk_freq - 1)/slot->fclk_freq;
+	tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
 	ndelay(8*tick_ns);
 
 	mmc_omap_start_command(host, data->stop);
···
 	u16 stat = 0;
 
 	/* Sending abort takes 80 clocks. Have some extra and round up */
-	timeout = (120*1000000 + slot->fclk_freq - 1)/slot->fclk_freq;
+	timeout = DIV_ROUND_UP(120 * USEC_PER_SEC, slot->fclk_freq);
 	restarts = 0;
 	while (restarts < maxloops) {
 		OMAP_MMC_WRITE(host, STAT, 0xFFFF);
···
 	if (n > host->buffer_bytes_left)
 		n = host->buffer_bytes_left;
 
-	nwords = n / 2;
-	nwords += n & 1; /* handle odd number of bytes to transfer */
+	/* Round up to handle odd number of bytes to transfer */
+	nwords = DIV_ROUND_UP(n, 2);
 
 	host->buffer_bytes_left -= n;
 	host->total_bytes_left -= n;