mmc: mediatek: Fixed bug where clock frequency could be set wrong

This patch can fix two issues: Issue 1: In previous code, div may be overflow when setting clock frequency as f_min. We can use DIV_ROUND_UP to fix this boundary related issue. Issue 2: In previous code, we can not set the correct clock frequency when div equals 0xff. Signed-off-by: Yong Mao <[email protected]> Signed-off-by: Chaotian Jing <[email protected]> Reviewed-by: Daniel Kurtz <[email protected]> Signed-off-by: Ulf Hansson <[email protected]>
SELinuxProject · Mar 16, 2017 · 40ceda0 · 40ceda0
1 parent 8ecc344
commit 40ceda0
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
@@ -580,7 +580,7 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz)
 		}
 	}
 	sdr_set_field(host->base + MSDC_CFG, MSDC_CFG_CKMOD | MSDC_CFG_CKDIV,
-			(mode << 8) | (div % 0xff));
+		      (mode << 8) | div);
 	sdr_set_bits(host->base + MSDC_CFG, MSDC_CFG_CKPDN);
 	while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB))
 		cpu_relax();
@@ -1559,7 +1559,7 @@ static int msdc_drv_probe(struct platform_device *pdev)
 	host->src_clk_freq = clk_get_rate(host->src_clk);
 	/* Set host parameters to mmc */
 	mmc->ops = &mt_msdc_ops;
-	mmc->f_min = host->src_clk_freq / (4 * 255);
+	mmc->f_min = DIV_ROUND_UP(host->src_clk_freq, 4 * 255);
 
 	mmc->caps |= MMC_CAP_ERASE | MMC_CAP_CMD23;
 	/* MMC core transfer sizes tunable parameters */