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-rw-r--r--drivers/i2c/busses/i2c-rk3x.c11
1 files changed, 5 insertions, 6 deletions
diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c
index e637c32ae517..93cfc837200b 100644
--- a/drivers/i2c/busses/i2c-rk3x.c
+++ b/drivers/i2c/busses/i2c-rk3x.c
@@ -433,12 +433,11 @@ static void rk3x_i2c_set_scl_rate(struct rk3x_i2c *i2c, unsigned long scl_rate)
unsigned long i2c_rate = clk_get_rate(i2c->clk);
unsigned int div;
- /* SCL rate = (clk rate) / (8 * DIV) */
- div = DIV_ROUND_UP(i2c_rate, scl_rate * 8);
-
- /* The lower and upper half of the CLKDIV reg describe the length of
- * SCL low & high periods. */
- div = DIV_ROUND_UP(div, 2);
+ /* set DIV = DIVH = DIVL
+ * SCL rate = (clk rate) / (8 * (DIVH + 1 + DIVL + 1))
+ * = (clk rate) / (16 * (DIV + 1))
+ */
+ div = DIV_ROUND_UP(i2c_rate, scl_rate * 16) - 1;
i2c_writel(i2c, (div << 16) | (div & 0xffff), REG_CLKDIV);
}