i2c: mxc: refactor i2c driver and support dm

1. Introduce a new structure `struct mxc_i2c_bus`, this structure will
   used for non-DM and DM.
2. Remove `struct mxc_i2c_regs` structure, but use register offset to access
   registers based on `base` entry of `struct mxc_i2c_bus`.
3. Remove most `#ifdef I2C_QUIRK_REG`. Using driver_data to contain platform
   flags. A new flag is introduced, I2C_QUIRK_FLAG.
4. Most functions use `struct mxc_i2c_bus` as one of the parameters.
   Make most functions common to DM and non-DM, try to avoid duplicated code.
5. Support DM, but pinctrl is not included. Pinmux setting is still set
   by setup_i2c, but we do not need bus_i2c_init for DM.
6. struct i2c_parms and struct sram_data are removed.
7. Remove bus_i2c_read bus_i2c_write prototype in header file. The frist
   paramter of bus_i2c_init is modified to i2c index. Add new prototype
   i2c_idle_bus and force_bus_idle. Since bus_i2c_init is not good for
   DM I2C and pinctrl is missed, we use a weak function for i2c_idle_bus.
   Board file take the responsibility to implement this function, like this:
   "
   int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
   {
	   if (i2c_bus->index == 0)
		   force_bus_idle(i2c_pads_info0);
	   else if (i2c_bus->index == 1)
		   force_bus_idle(i2c_pads_info1);
	   else
		   xxxxxx
   }
   "
8. Introduce a weak function, enable_i2c_clk
9. Tested on an i.MX7 platform. Log info:
 => dm tree
 Class       Probed   Name
 ----------------------------------------
 root        [ + ]    root_driver
 simple_bus  [   ]    |-- soc
 simple_bus  [   ]    |   |-- aips-bus@30000000
 simple_bus  [   ]    |   |   |-- anatop@30360000
 simple_bus  [   ]    |   |   `-- snvs@30370000
 simple_bus  [   ]    |   |-- aips-bus@30400000
 simple_bus  [   ]    |   `-- aips-bus@30800000
 i2c         [   ]    |       |-- i2c@30a20000
 i2c         [   ]    |       `-- i2c@30a40000
 simple_bus  [   ]    `-- regulators
 => i2c dev 0
 Setting bus to 0
 => i2c probe
 Valid chip addresses: 08 50
 => i2c md 8 31
 0031: 08 08 08 08 08 08 08 08 08 08 08 08 08 08 08 08

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Acked-by: Simon Glass <sjg@chromium.org>

2 files changed, 37 insertions, 8 deletions

diff --git a/arch/arm/imx-common/i2c-mxv7.c b/arch/arm/imx-common/i2c-mxv7.c
index 1a632e7..f3a5c3f 100644
--- a/arch/arm/imx-common/i2c-mxv7.c
+++ b/arch/arm/imx-common/i2c-mxv7.c
@@ -12,7 +12,7 @@
 #include <asm/imx-common/mxc_i2c.h>
 #include <watchdog.h>
 
-static int force_idle_bus(void *priv)
+int force_idle_bus(void *priv)
 {
 	int i;
 	int sda, scl;
@@ -99,8 +99,9 @@ int setup_i2c(unsigned i2c_index, int speed, int slave_addr,
 	if (ret)
 		goto err_idle;
 
-	bus_i2c_init(i2c_bases[i2c_index], speed, slave_addr,
-			force_idle_bus, p);
+#ifndef CONFIG_DM_I2C
+	bus_i2c_init(i2c_index, speed, slave_addr, force_idle_bus, p);
+#endif
 
 	return 0;
 
diff --git a/arch/arm/include/asm/imx-common/mxc_i2c.h b/arch/arm/include/asm/imx-common/mxc_i2c.h
index af86163..355b25e 100644
--- a/arch/arm/include/asm/imx-common/mxc_i2c.h
+++ b/arch/arm/include/asm/imx-common/mxc_i2c.h
@@ -19,6 +19,36 @@ struct i2c_pads_info {
 	struct i2c_pin_ctrl sda;
 };
 
+/*
+ * Information about i2c controller
+ * struct mxc_i2c_bus - information about the i2c[x] bus
+ * @index: i2c bus index
+ * @base: Address of I2C bus controller
+ * @driver_data: Flags for different platforms, such as I2C_QUIRK_FLAG.
+ * @speed: Speed of I2C bus
+ * @pads_info: pinctrl info for this i2c bus, will be used when pinctrl is ok.
+ * The following two is only to be compatible with non-DM part.
+ * @idle_bus_fn: function to force bus idle
+ * @idle_bus_data: parameter for idle_bus_fun
+ */
+struct mxc_i2c_bus {
+	/*
+	 * board file can use this index to locate which i2c_pads_info is for
+	 * i2c_idle_bus. When pinmux is implement, this entry can be
+	 * discarded. Here we do not use dev->seq, because we do not want to
+	 * export device to board file.
+	 */
+	int index;
+	ulong base;
+	ulong driver_data;
+	int speed;
+	struct i2c_pads_info *pads_info;
+#ifndef CONFIG_DM_I2C
+	int (*idle_bus_fn)(void *p);
+	void *idle_bus_data;
+#endif
+};
+
 #if defined(CONFIG_MX6QDL)
 #define I2C_PADS(name, scl_i2c, scl_gpio, scl_gp, sda_i2c, sda_gpio, sda_gp) \
 	struct i2c_pads_info mx6q_##name = {		\
@@ -54,10 +84,8 @@ struct i2c_pads_info {
 
 int setup_i2c(unsigned i2c_index, int speed, int slave_addr,
 	      struct i2c_pads_info *p);
-void bus_i2c_init(void *base, int speed, int slave_addr,
+void bus_i2c_init(int index, int speed, int slave_addr,
 		int (*idle_bus_fn)(void *p), void *p);
-int bus_i2c_read(void *base, uchar chip, uint addr, int alen, uchar *buf,
-		int len);
-int bus_i2c_write(void *base, uchar chip, uint addr, int alen,
-		const uchar *buf, int len);
+int force_idle_bus(void *priv);
+int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus);
 #endif