1 files changed, 293 insertions, 0 deletions

diff --git a/target/linux/realtek/files-5.10/drivers/i2c/muxes/i2c-mux-rtl9300.c b/target/linux/realtek/files-5.10/drivers/i2c/muxes/i2c-mux-rtl9300.c
new file mode 100644
index 0000000000..2f45b0a3cc
--- /dev/null
+++ b/target/linux/realtek/files-5.10/drivers/i2c/muxes/i2c-mux-rtl9300.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * I2C multiplexer for the 2 I2C Masters of the RTL9300
+ * with up to 8 channels each, but which are not entirely
+ * independent of each other
+ */
+#include <linux/i2c-mux.h>
+#include <linux/module.h>
+#include <linux/mux/consumer.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+
+#include "../busses/i2c-rtl9300.h"
+
+#define NUM_MASTERS		2
+#define NUM_BUSSES		8
+
+#define REG(mst, x)	(mux->base + x + (mst ? mux->i2c->mst2_offset : 0))
+#define REG_MASK(mst, clear, set, reg)	\
+			writel((readl(REG((mst),(reg))) & ~(clear)) | (set), REG((mst),(reg)))
+
+struct channel {
+	u8 sda_num;
+	u8 scl_num;
+};
+
+static struct channel channels[NUM_MASTERS * NUM_BUSSES];
+
+struct rtl9300_mux {
+	void __iomem *base;
+	struct device *dev;
+	struct i2c_adapter *parent;
+	struct rtl9300_i2c * i2c;
+};
+
+struct i2c_mux_data  {
+	int scl0_pin;
+	int scl1_pin;
+	int sda0_pin;
+	int sda_pins;
+	int (*i2c_mux_select)(struct i2c_mux_core *muxc, u32 chan);
+	int (*i2c_mux_deselect)(struct i2c_mux_core *muxc, u32 chan);
+	void (*sda_sel)(struct i2c_mux_core *muxc, int pin);
+};
+
+static int rtl9300_i2c_mux_select(struct i2c_mux_core *muxc, u32 chan)
+{
+	struct rtl9300_mux *mux = i2c_mux_priv(muxc);
+
+	// Set SCL pin
+	REG_MASK(channels[chan].scl_num, 0,
+		 BIT(RTL9300_I2C_CTRL1_GPIO8_SCL_SEL), RTL9300_I2C_CTRL1);
+
+	// Set SDA pin
+	REG_MASK(channels[chan].scl_num, 0x7 << RTL9300_I2C_CTRL1_SDA_OUT_SEL,
+		 channels[chan].sda_num << RTL9300_I2C_CTRL1_SDA_OUT_SEL, RTL9300_I2C_CTRL1);
+
+	mux->i2c->sda_num = channels[chan].sda_num;
+	mux->i2c->scl_num = channels[chan].scl_num;
+
+	return 0;
+}
+
+static int rtl9310_i2c_mux_select(struct i2c_mux_core *muxc, u32 chan)
+{
+	struct rtl9300_mux *mux = i2c_mux_priv(muxc);
+
+	// Set SCL pin
+	REG_MASK(0, 0, BIT(RTL9310_I2C_MST_IF_SEL_GPIO_SCL_SEL + channels[chan].scl_num),
+		 RTL9310_I2C_MST_IF_SEL);
+
+	// Set SDA pin
+	REG_MASK(channels[chan].scl_num, 0xf << RTL9310_I2C_CTRL_SDA_OUT_SEL,
+		 channels[chan].sda_num << RTL9310_I2C_CTRL_SDA_OUT_SEL, RTL9310_I2C_CTRL);
+
+	mux->i2c->sda_num = channels[chan].sda_num;
+	mux->i2c->scl_num = channels[chan].scl_num;
+
+	return 0;
+}
+
+static int rtl9300_i2c_mux_deselect(struct i2c_mux_core *muxc, u32 chan)
+{
+	return 0;
+}
+
+static void rtl9300_sda_sel(struct i2c_mux_core *muxc, int pin)
+{
+	struct rtl9300_mux *mux = i2c_mux_priv(muxc);
+	u32 v;
+
+	// Set SDA pin to I2C functionality
+	v = readl(REG(0, RTL9300_I2C_MST_GLB_CTRL));
+	v |= BIT(pin);
+	writel(v, REG(0, RTL9300_I2C_MST_GLB_CTRL));
+}
+
+static void rtl9310_sda_sel(struct i2c_mux_core *muxc, int pin)
+{
+	struct rtl9300_mux *mux = i2c_mux_priv(muxc);
+	u32 v;
+
+	// Set SDA pin to I2C functionality
+	v = readl(REG(0, RTL9310_I2C_MST_IF_SEL));
+	v |= BIT(pin);
+	writel(v, REG(0, RTL9310_I2C_MST_IF_SEL));
+}
+
+static struct device_node *mux_parent_adapter(struct device *dev, struct rtl9300_mux *mux)
+{
+	struct device_node *node = dev->of_node;
+	struct device_node *parent_np;
+	struct i2c_adapter *parent;
+
+	parent_np = of_parse_phandle(node, "i2c-parent", 0);
+	if (!parent_np) {
+		dev_err(dev, "Cannot parse i2c-parent\n");
+		return ERR_PTR(-ENODEV);
+	}
+	parent = of_find_i2c_adapter_by_node(parent_np);
+	of_node_put(parent_np);
+	if (!parent)
+		return ERR_PTR(-EPROBE_DEFER);
+
+	if (!(of_device_is_compatible(parent_np, "realtek,rtl9300-i2c")
+		|| of_device_is_compatible(parent_np, "realtek,rtl9310-i2c"))){
+		dev_err(dev, "I2C parent not an RTL9300 I2C controller\n");
+		return ERR_PTR(-ENODEV);
+	}
+
+	mux->parent = parent;
+	mux->i2c = (struct rtl9300_i2c *)i2c_get_adapdata(parent);
+	mux->base = mux->i2c->base;
+
+	return parent_np;
+}
+
+struct i2c_mux_data rtl9300_i2c_mux_data = {
+	.scl0_pin = 8,
+	.scl1_pin = 17,
+	.sda0_pin = 9,
+	.sda_pins = 8,
+	.i2c_mux_select = rtl9300_i2c_mux_select,
+	.i2c_mux_deselect = rtl9300_i2c_mux_deselect,
+	.sda_sel = rtl9300_sda_sel,
+};
+
+struct i2c_mux_data rtl9310_i2c_mux_data = {
+	.scl0_pin = 13, 
+	.scl1_pin = 14,
+	.sda0_pin = 0,
+	.sda_pins = 16,
+	.i2c_mux_select = rtl9310_i2c_mux_select,
+	.i2c_mux_deselect = rtl9300_i2c_mux_deselect,
+	.sda_sel = rtl9310_sda_sel,
+};
+
+static const struct of_device_id rtl9300_i2c_mux_of_match[] = {
+	{ .compatible = "realtek,i2c-mux-rtl9300", .data = (void *) &rtl9300_i2c_mux_data},
+	{ .compatible = "realtek,i2c-mux-rtl9310", .data = (void *) &rtl9310_i2c_mux_data},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, rtl9300_i2c_mux_of_match);
+
+static int rtl9300_i2c_mux_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *node = dev->of_node;
+	struct device_node *parent_np;
+	struct device_node *child;
+	struct i2c_mux_core *muxc;
+	struct rtl9300_mux *mux;
+	struct i2c_mux_data *mux_data;
+	int children;
+	int ret;
+
+	pr_info("%s probing I2C adapter\n", __func__);
+	
+	if (!node) {
+		dev_err(dev, "No DT found\n");
+		return -EINVAL;
+	}
+
+	mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
+	if (!mux)
+		return -ENOMEM;
+
+	mux->dev = dev;
+
+	mux_data = (struct i2c_mux_data *) device_get_match_data(dev);
+
+	parent_np = mux_parent_adapter(dev, mux);
+	if (IS_ERR(parent_np))
+		return dev_err_probe(dev, PTR_ERR(parent_np), "i2c-parent adapter not found\n");
+
+	pr_info("%s base memory %08x\n", __func__, (u32)mux->base);
+
+	children = of_get_child_count(node);
+
+	muxc = i2c_mux_alloc(mux->parent, dev, children, 0, 0,
+			     mux_data->i2c_mux_select, mux_data->i2c_mux_deselect);
+	if (!muxc) {
+		ret = -ENOMEM;
+		goto err_parent;
+	}
+	muxc->priv = mux;
+
+	platform_set_drvdata(pdev, muxc);
+
+	for_each_child_of_node(node, child) {
+		u32 chan;
+		u32 pin;
+
+		ret = of_property_read_u32(child, "reg", &chan);
+		if (ret < 0) {
+			dev_err(dev, "no reg property for node '%pOFn'\n",
+				child);
+			goto err_children;
+		}
+
+		if (chan >= NUM_MASTERS * NUM_BUSSES) {
+			dev_err(dev, "invalid reg %u\n", chan);
+			ret = -EINVAL;
+			goto err_children;
+		}
+
+		if (of_property_read_u32(child, "scl-pin", &pin)) {
+			dev_warn(dev, "SCL pin not found in DT, using default\n");
+			pin = mux_data->scl0_pin;
+		}
+		if (!(pin == mux_data->scl0_pin || pin == mux_data->scl1_pin)) {
+			dev_warn(dev, "SCL pin %d not supported\n", pin);
+			ret = -EINVAL;
+			goto err_children;
+		}
+		channels[chan].scl_num = pin == mux_data->scl0_pin ? 0 : 1;
+		pr_info("%s channel %d scl_num %d\n", __func__, chan, channels[chan].scl_num);
+
+		if (of_property_read_u32(child, "sda-pin", &pin)) {
+			dev_warn(dev, "SDA pin not found in DT, using default \n");
+			pin = mux_data->sda0_pin;
+		}
+		channels[chan].sda_num = pin - mux_data->sda0_pin;
+		if (channels[chan].sda_num < 0 || channels[chan].sda_num >= mux_data->sda_pins) {
+			dev_warn(dev, "SDA pin %d not supported\n", pin);
+			return -EINVAL;
+		}
+		pr_info("%s channel %d sda_num %d\n", __func__, chan, channels[chan].sda_num);
+
+		mux_data->sda_sel(muxc, channels[chan].sda_num);
+
+		ret = i2c_mux_add_adapter(muxc, 0, chan, 0);
+		if (ret)
+			goto err_children;
+	}
+
+	dev_info(dev, "%d-port mux on %s adapter\n", children, mux->parent->name);
+
+	return 0;
+
+err_children:
+	i2c_mux_del_adapters(muxc);
+err_parent:
+	i2c_put_adapter(mux->parent);
+
+	return ret;
+}
+
+static int rtl9300_i2c_mux_remove(struct platform_device *pdev)
+{
+	struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
+
+	i2c_mux_del_adapters(muxc);
+	i2c_put_adapter(muxc->parent);
+
+	return 0;
+}
+
+static struct platform_driver i2c_mux_driver = {
+	.probe	= rtl9300_i2c_mux_probe,
+	.remove	= rtl9300_i2c_mux_remove,
+	.driver	= {
+		.name	= "i2c-mux-rtl9300",
+		.of_match_table = rtl9300_i2c_mux_of_match,
+	},
+};
+module_platform_driver(i2c_mux_driver);
+
+MODULE_DESCRIPTION("RTL9300 I2C multiplexer driver");
+MODULE_AUTHOR("Birger Koblitz");
+MODULE_LICENSE("GPL v2");