From: Gustavo A. R. Silva Date: Tue, 11 Feb 2020 14:47:04 +0000 (-0600) Subject: i2c: altera: Fix potential integer overflow X-Git-Tag: microblaze-v5.10~1331^2~1 X-Git-Url: http://git.monstr.eu/?a=commitdiff_plain;h=54498e8070e19e74498a72c7331348143e7e1f8c;p=linux-2.6-microblaze.git i2c: altera: Fix potential integer overflow Factor out 100 from the equation and do 32-bit arithmetic (3 * clk_mhz / 10) instead of 64-bit. Notice that clk_mhz is MHz, so the multiplication will never wrap 32 bits and there is no need for div_u64(). Addresses-Coverity: 1458369 ("Unintentional integer overflow") Fixes: 0560ad576268 ("i2c: altera: Add Altera I2C Controller driver") Suggested-by: David Laight Signed-off-by: Gustavo A. R. Silva Reviewed-by: Thor Thayer Signed-off-by: Wolfram Sang --- diff --git a/drivers/i2c/busses/i2c-altera.c b/drivers/i2c/busses/i2c-altera.c index 5255d3755411..1de23b4f3809 100644 --- a/drivers/i2c/busses/i2c-altera.c +++ b/drivers/i2c/busses/i2c-altera.c @@ -171,7 +171,7 @@ static void altr_i2c_init(struct altr_i2c_dev *idev) /* SCL Low Time */ writel(t_low, idev->base + ALTR_I2C_SCL_LOW); /* SDA Hold Time, 300ns */ - writel(div_u64(300 * clk_mhz, 1000), idev->base + ALTR_I2C_SDA_HOLD); + writel(3 * clk_mhz / 10, idev->base + ALTR_I2C_SDA_HOLD); /* Mask all master interrupt bits */ altr_i2c_int_enable(idev, ALTR_I2C_ALL_IRQ, false);