2 files changed, 23 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index f325ec7abfb1..dbecf08399f8 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -317,6 +317,12 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
                                 47,     /* tLOW = 4.7 us */
                                 3,      /* tf = 0.3 us */
                                 0);     /* No offset */
+
+        /* Allow platforms to specify the ideal HCNT and LCNT values */
+        if (dev->ss_hcnt && dev->ss_lcnt) {
+                hcnt = dev->ss_hcnt;
+                lcnt = dev->ss_lcnt;
+        }
         dw_writel(dev, hcnt, DW_IC_SS_SCL_HCNT);
         dw_writel(dev, lcnt, DW_IC_SS_SCL_LCNT);
         dev_dbg(dev->dev, "Standard-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
@@ -331,6 +337,11 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
                                 13,     /* tLOW = 1.3 us */
                                 3,      /* tf = 0.3 us */
                                 0);     /* No offset */
+
+        if (dev->fs_hcnt && dev->fs_lcnt) {
+                hcnt = dev->fs_hcnt;
+                lcnt = dev->fs_lcnt;
+        }
         dw_writel(dev, hcnt, DW_IC_FS_SCL_HCNT);
         dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT);
         dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 912aa2262866..e8a756537ed0 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -61,6 +61,14 @@
  * @tx_fifo_depth: depth of the hardware tx fifo
  * @rx_fifo_depth: depth of the hardware rx fifo
  * @rx_outstanding: current master-rx elements in tx fifo
+ * @ss_hcnt: standard speed HCNT value
+ * @ss_lcnt: standard speed LCNT value
+ * @fs_hcnt: fast speed HCNT value
+ * @fs_lcnt: fast speed LCNT value
+ *
+ * HCNT and LCNT parameters can be used if the platform knows more accurate
+ * values than the one computed based only on the input clock frequency.
+ * Leave them to be %0 if not used.
  */
 struct dw_i2c_dev {
         struct device           *dev;
@@ -91,6 +99,10 @@ struct dw_i2c_dev {
         unsigned int            rx_fifo_depth;
         int                     rx_outstanding;
         u32                     sda_hold_time;
+        u16                     ss_hcnt;
+        u16                     ss_lcnt;
+        u16                     fs_hcnt;
+        u16                     fs_lcnt;
 };
 
 #define ACCESS_SWAP             0x00000001