i2c: aspeed: Retain delay/setup/hold values when configuring bus frequency

[platform/kernel/linux-rpi.git] / drivers / i2c / busses / i2c-aspeed.c

diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index 60afab8..645e007 100644 (file)
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/drivers/i2c/busses/i2c-aspeed.c
@@ -53,6 +53,9 @@
 #define ASPEED_I2CD_MASTER_EN                          BIT(0)
 
 /* 0x04 : I2CD Clock and AC Timing Control Register #1 */
+#define ASPEED_I2CD_TIME_TBUF_MASK                     GENMASK(31, 28)
+#define ASPEED_I2CD_TIME_THDSTA_MASK                   GENMASK(27, 24)
+#define ASPEED_I2CD_TIME_TACST_MASK                    GENMASK(23, 20)
 #define ASPEED_I2CD_TIME_SCL_HIGH_SHIFT                        16
 #define ASPEED_I2CD_TIME_SCL_HIGH_MASK                 GENMASK(19, 16)
 #define ASPEED_I2CD_TIME_SCL_LOW_SHIFT                 12
@@ -743,7 +746,11 @@ static int aspeed_i2c_init_clk(struct aspeed_i2c_bus *bus)
        u32 divisor, clk_reg_val;
 
        divisor = DIV_ROUND_UP(bus->parent_clk_frequency, bus->bus_frequency);
-       clk_reg_val = bus->get_clk_reg_val(divisor);
+       clk_reg_val = readl(bus->base + ASPEED_I2C_AC_TIMING_REG1);
+       clk_reg_val &= (ASPEED_I2CD_TIME_TBUF_MASK |
+                       ASPEED_I2CD_TIME_THDSTA_MASK |
+                       ASPEED_I2CD_TIME_TACST_MASK);
+       clk_reg_val |= bus->get_clk_reg_val(divisor);
        writel(clk_reg_val, bus->base + ASPEED_I2C_AC_TIMING_REG1);
        writel(ASPEED_NO_TIMEOUT_CTRL, bus->base + ASPEED_I2C_AC_TIMING_REG2);