[PATCH 2/3] i2c: add RTL9310 support to RTL9300 I2C controller driver

[Jonas Jelonek <jelonek.jonas@gmail.com>]

This adds support for the internal I2C controllers of RTL9310 series
based chip to the driver for RTL9300. Adds driver data with register
definitions, a chip-specific function and a generic compatible string
for the whole RTL9310 series because as of now there are no differences
between the different variants (RTL9311, RTL9312, RTL9313).

Also adds a new device tree property 'scl-num' which needs to be
specified in case both or only the second master is used. This is
required due to the register layout in contrast to RTL9300 which has
SCL selection in a global register instead of a master-specific one.

Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
---
 drivers/i2c/busses/i2c-rtl9300.c | 39 +++++++++++++++++++++++++++++++-
 1 file changed, 38 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-rtl9300.c b/drivers/i2c/busses/i2c-rtl9300.c
index f8e81102ee74..fae6eb39adfd 100644
--- a/drivers/i2c/busses/i2c-rtl9300.c
+++ b/drivers/i2c/busses/i2c-rtl9300.c
@@ -59,6 +59,7 @@ struct rtl9300_i2c_drv_data {
 };
 
 #define RTL9300_I2C_MUX_NCHAN	8
+#define RTL9310_I2C_MUX_NCHAN	12
 
 struct rtl9300_i2c {
 	struct regmap *regmap;
@@ -67,6 +68,7 @@ struct rtl9300_i2c {
 	struct regmap_field *fields[F_NUM_FIELDS];
 	u32 reg_base;
 	u32 data_reg;
+	u8 scl_num;
 	u8 sda_pin;
 	struct mutex lock;
 };
@@ -79,6 +81,11 @@ struct rtl9300_i2c {
 #define RTL9300_I2C_MST_DATA_WORD3			0x14
 #define RTL9300_I2C_MST_GLB_CTRL			0x384
 
+#define RTL9310_I2C_MST_IF_CTRL				0x1004
+#define	RTL9310_I2C_MST_IF_SEL				0x1008
+#define	RTL9310_I2C_MST_CTRL				0x0
+#define	RTL9310_I2C_MST_MEMADDR_CTRL			0x4
+#define RTL9310_I2C_MST_DATA_CTRL			0x8
 
 static int rtl9300_i2c_reg_addr_set(struct rtl9300_i2c *i2c, u32 reg, u16 len)
 {
@@ -96,6 +103,11 @@ static int rtl9300_i2c_select_scl(struct rtl9300_i2c *i2c, u8 scl)
 	return regmap_field_write(i2c->fields[F_SCL_SEL], 1);
 }
 
+static int rtl9310_i2c_select_scl(struct rtl9300_i2c *i2c, u8 scl)
+{
+	return regmap_field_update_bits(i2c->fields[F_SCL_SEL], BIT(scl), BIT(scl));
+}
+
 static int rtl9300_i2c_config_io(struct rtl9300_i2c *i2c, u8 sda_pin)
 {
 	struct rtl9300_i2c_drv_data *drv_data;
@@ -111,7 +123,7 @@ static int rtl9300_i2c_config_io(struct rtl9300_i2c *i2c, u8 sda_pin)
 	if (ret)
 		return ret;
 
-	return drv_data->select_scl(i2c, 0);
+	return drv_data->select_scl(i2c, i2c->scl_num);
 }
 
 static int rtl9300_i2c_config_xfer(struct rtl9300_i2c *i2c, struct rtl9300_i2c_chan *chan,
@@ -366,6 +378,10 @@ static int rtl9300_i2c_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	ret = device_property_read_u8(dev, "scl-num", &i2c->scl_num);
+	if (ret || (i2c->scl_num != 0 && i2c->scl_num != 1))
+		i2c->scl_num = 0;
+
 	platform_set_drvdata(pdev, i2c);
 
 	drv_data = (struct rtl9300_i2c_drv_data *)device_get_match_data(i2c->dev);
@@ -457,12 +473,33 @@ static const struct rtl9300_i2c_drv_data rtl9300_i2c_drv_data = {
 	.max_nchan = RTL9300_I2C_MUX_NCHAN,
 };
 
+static const struct rtl9300_i2c_drv_data rtl9310_i2c_drv_data = {
+	.field_desc = {
+		[F_SCL_SEL]		= GLB_REG_FIELD(RTL9310_I2C_MST_IF_SEL, 12, 13),
+		[F_SDA_SEL]		= GLB_REG_FIELD(RTL9310_I2C_MST_IF_SEL, 0, 11),
+		[F_SCL_FREQ]		= MST_REG_FIELD(RTL9310_I2C_MST_CTRL, 30, 31),
+		[F_DEV_ADDR]		= MST_REG_FIELD(RTL9310_I2C_MST_CTRL, 11, 17),
+		[F_SDA_OUT_SEL]		= MST_REG_FIELD(RTL9310_I2C_MST_CTRL, 18, 21),
+		[F_MEM_ADDR_WIDTH]	= MST_REG_FIELD(RTL9310_I2C_MST_CTRL, 9, 10),
+		[F_DATA_WIDTH]		= MST_REG_FIELD(RTL9310_I2C_MST_CTRL, 5, 8),
+		[F_RD_MODE]		= MST_REG_FIELD(RTL9310_I2C_MST_CTRL, 4, 4),
+		[F_RWOP]		= MST_REG_FIELD(RTL9310_I2C_MST_CTRL, 2, 2),
+		[F_I2C_FAIL]		= MST_REG_FIELD(RTL9310_I2C_MST_CTRL, 1, 1),
+		[F_I2C_TRIG]		= MST_REG_FIELD(RTL9310_I2C_MST_CTRL, 0, 0),
+		[F_MEM_ADDR]		= MST_REG_FIELD(RTL9310_I2C_MST_MEMADDR_CTRL, 0, 23),
+	},
+	.select_scl = rtl9310_i2c_select_scl,
+	.data_reg = RTL9310_I2C_MST_DATA_CTRL,
+	.max_nchan = RTL9310_I2C_MUX_NCHAN,
+};
+
 
 static const struct of_device_id i2c_rtl9300_dt_ids[] = {
 	{ .compatible = "realtek,rtl9301-i2c", .data = (void *) &rtl9300_i2c_drv_data },
 	{ .compatible = "realtek,rtl9302b-i2c", .data = (void *) &rtl9300_i2c_drv_data },
 	{ .compatible = "realtek,rtl9302c-i2c", .data = (void *) &rtl9300_i2c_drv_data },
 	{ .compatible = "realtek,rtl9303-i2c", .data = (void *) &rtl9300_i2c_drv_data },
+	{ .compatible = "realtek,rtl9310-i2c", .data = (void *) &rtl9310_i2c_drv_data },
 	{}
 };
 MODULE_DEVICE_TABLE(of, i2c_rtl9300_dt_ids);
-- 
2.48.1