[PATCH] i2c: meson: add configurable divider factors

[glaroque@baylibre.com]

This patch add support for I2C controller in Meson-AXG SoC,
Due to the IP changes between I2C controller, we need to introduce
a compatible data to make the divider factor configurable.

backport from linux:
931b18e92cd0 ("2c: meson: add configurable divider factors")

Signed-off-by: Guillaume La Roque <glaroque@baylibre.com>
---
 drivers/i2c/meson_i2c.c | 30 +++++++++++++++++++++++++-----
 1 file changed, 25 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/meson_i2c.c b/drivers/i2c/meson_i2c.c
index 7d06d95cf3..ee59bac123 100644
--- a/drivers/i2c/meson_i2c.c
+++ b/drivers/i2c/meson_i2c.c
@@ -41,7 +41,12 @@ struct i2c_regs {
 	u32 tok_rdata1;
 };
 
+struct meson_i2c_data {
+	unsigned char div_factor;
+};
+
 struct meson_i2c {
+	const struct meson_i2c_data *data;
 	struct clk clk;
 	struct i2c_regs *regs;
 	struct i2c_msg *msg;	/* Current I2C message */
@@ -229,7 +234,7 @@ static int meson_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
 	if (IS_ERR_VALUE(clk_rate))
 		return -EINVAL;
 
-	div = DIV_ROUND_UP(clk_rate, speed * 4);
+	div = DIV_ROUND_UP(clk_rate, speed * i2c->data->div_factor);
 
 	/* clock divider has 12 bits */
 	if (div >= (1 << 12)) {
@@ -253,6 +258,8 @@ static int meson_i2c_probe(struct udevice *bus)
 	struct meson_i2c *i2c = dev_get_priv(bus);
 	int ret;
 
+	i2c->data = (const struct meson_i2c_data *)dev_get_driver_data(bus);
+
 	ret = clk_get_by_index(bus, 0, &i2c->clk);
 	if (ret < 0)
 		return ret;
@@ -272,11 +279,24 @@ static const struct dm_i2c_ops meson_i2c_ops = {
 	.set_bus_speed = meson_i2c_set_bus_speed,
 };
 
+static const struct meson_i2c_data i2c_meson6_data = {
+	.div_factor = 4,
+};
+
+static const struct meson_i2c_data i2c_gxbb_data = {
+	.div_factor = 4,
+};
+
+static const struct meson_i2c_data i2c_axg_data = {
+	.div_factor = 3,
+};
+
 static const struct udevice_id meson_i2c_ids[] = {
-	{ .compatible = "amlogic,meson6-i2c" },
-	{ .compatible = "amlogic,meson-gx-i2c" },
-	{ .compatible = "amlogic,meson-gxbb-i2c" },
-	{ }
+	{.compatible = "amlogic,meson6-i2c", .data = (ulong)&i2c_meson6_data},
+	{.compatible = "amlogic,meson-gx-i2c", .data = (ulong)&i2c_gxbb_data},
+	{.compatible = "amlogic,meson-gxbb-i2c", .data = (ulong)&i2c_gxbb_data},
+	{.compatible = "amlogic,meson-axg-i2c", .data = (ulong)&i2c_axg_data},
+	{}
 };
 
 U_BOOT_DRIVER(i2c_meson) = {
-- 
2.17.1