i2c: designware: Tidy up PCI support

This is hacked into the driver at present. It seems better to have it as
a separate driver that uses the base driver. Create a new file and put
the X86 code into it.

Actually the Baytrail settings should really come from the device tree.

Note that 'has_max_speed' is added as well. This is currently always false
but since only Baytrail provides the config, it does not affect operation
for other devices.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/i2c/designware_i2c.h b/drivers/i2c/designware_i2c.h
index 20ff20d..48766d0 100644
--- a/drivers/i2c/designware_i2c.h
+++ b/drivers/i2c/designware_i2c.h
@@ -7,6 +7,8 @@
 #ifndef __DW_I2C_H_
 #define __DW_I2C_H_
 
+#include <reset.h>
+
 struct i2c_regs {
 	u32 ic_con;		/* 0x00 */
 	u32 ic_tar;		/* 0x04 */
@@ -131,4 +133,37 @@
 #define I2C_FAST_SPEED		400000
 #define I2C_STANDARD_SPEED	100000
 
+/**
+ * struct dw_scl_sda_cfg - I2C timing configuration
+ *
+ * @has_max_speed: Support maximum speed (1Mbps)
+ * @ss_hcnt: Standard speed high time in ns
+ * @fs_hcnt: Fast speed high time in ns
+ * @ss_lcnt: Standard speed low time in ns
+ * @fs_lcnt: Fast speed low time in ns
+ * @sda_hold: SDA hold time
+ */
+struct dw_scl_sda_cfg {
+	bool has_max_speed;
+	u32 ss_hcnt;
+	u32 fs_hcnt;
+	u32 ss_lcnt;
+	u32 fs_lcnt;
+	u32 sda_hold;
+};
+
+struct dw_i2c {
+	struct i2c_regs *regs;
+	struct dw_scl_sda_cfg *scl_sda_cfg;
+	struct reset_ctl_bulk resets;
+#if CONFIG_IS_ENABLED(CLK)
+	struct clk clk;
+#endif
+};
+
+extern const struct dm_i2c_ops designware_i2c_ops;
+
+int designware_i2c_probe(struct udevice *bus);
+int designware_i2c_remove(struct udevice *dev);
+
 #endif /* __DW_I2C_H_ */