1 files changed, 539 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-rtl9300.c b/drivers/i2c/busses/i2c-rtl9300.c
new file mode 100644
index 000000000000..4723e48cfe18
--- /dev/null
+++ b/drivers/i2c/busses/i2c-rtl9300.c
@@ -0,0 +1,539 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/bits.h>
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/unaligned.h>
+
+enum rtl9300_bus_freq {
+	RTL9300_I2C_STD_FREQ,
+	RTL9300_I2C_FAST_FREQ,
+};
+
+struct rtl9300_i2c;
+
+struct rtl9300_i2c_chan {
+	struct i2c_adapter adap;
+	struct rtl9300_i2c *i2c;
+	enum rtl9300_bus_freq bus_freq;
+	u8 sda_num;
+};
+
+enum rtl9300_i2c_reg_scope {
+	REG_SCOPE_GLOBAL,
+	REG_SCOPE_MASTER,
+};
+
+struct rtl9300_i2c_reg_field {
+	struct reg_field field;
+	enum rtl9300_i2c_reg_scope scope;
+};
+
+enum rtl9300_i2c_reg_fields {
+	F_DATA_WIDTH = 0,
+	F_DEV_ADDR,
+	F_I2C_FAIL,
+	F_I2C_TRIG,
+	F_MEM_ADDR,
+	F_MEM_ADDR_WIDTH,
+	F_RD_MODE,
+	F_RWOP,
+	F_SCL_FREQ,
+	F_SCL_SEL,
+	F_SDA_OUT_SEL,
+	F_SDA_SEL,
+
+	/* keep last */
+	F_NUM_FIELDS
+};
+
+struct rtl9300_i2c_drv_data {
+	struct rtl9300_i2c_reg_field field_desc[F_NUM_FIELDS];
+	int (*select_scl)(struct rtl9300_i2c *i2c, u8 scl);
+	u32 data_reg;
+	u8 max_nchan;
+};
+
+#define RTL9300_I2C_MUX_NCHAN	8
+#define RTL9310_I2C_MUX_NCHAN	12
+
+struct rtl9300_i2c {
+	struct regmap *regmap;
+	struct device *dev;
+	struct rtl9300_i2c_chan chans[RTL9310_I2C_MUX_NCHAN];
+	struct regmap_field *fields[F_NUM_FIELDS];
+	u32 reg_base;
+	u32 data_reg;
+	u8 scl_num;
+	u8 sda_num;
+	struct mutex lock;
+};
+
+DEFINE_GUARD(rtl9300_i2c, struct rtl9300_i2c *, mutex_lock(&_T->lock), mutex_unlock(&_T->lock))
+
+enum rtl9300_i2c_xfer_type {
+	RTL9300_I2C_XFER_BYTE,
+	RTL9300_I2C_XFER_WORD,
+	RTL9300_I2C_XFER_BLOCK,
+};
+
+struct rtl9300_i2c_xfer {
+	enum rtl9300_i2c_xfer_type type;
+	u16 dev_addr;
+	u8 reg_addr;
+	u8 reg_addr_len;
+	u8 *data;
+	u8 data_len;
+	bool write;
+};
+
+#define RTL9300_I2C_MST_CTRL1				0x0
+#define RTL9300_I2C_MST_CTRL2				0x4
+#define RTL9300_I2C_MST_DATA_WORD0			0x8
+#define RTL9300_I2C_MST_DATA_WORD1			0xc
+#define RTL9300_I2C_MST_DATA_WORD2			0x10
+#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)
+{
+	int ret;
+
+	ret = regmap_field_write(i2c->fields[F_MEM_ADDR_WIDTH], len);
+	if (ret)
+		return ret;
+
+	return regmap_field_write(i2c->fields[F_MEM_ADDR], reg);
+}
+
+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_chan(struct rtl9300_i2c *i2c, struct rtl9300_i2c_chan *chan)
+{
+	struct rtl9300_i2c_drv_data *drv_data;
+	int ret;
+
+	if (i2c->sda_num == chan->sda_num)
+		return 0;
+
+	ret = regmap_field_write(i2c->fields[F_SCL_FREQ], chan->bus_freq);
+	if (ret)
+		return ret;
+
+	drv_data = (struct rtl9300_i2c_drv_data *)device_get_match_data(i2c->dev);
+	ret = drv_data->select_scl(i2c, i2c->scl_num);
+	if (ret)
+		return ret;
+
+	ret = regmap_field_update_bits(i2c->fields[F_SDA_SEL], BIT(chan->sda_num),
+				       BIT(chan->sda_num));
+	if (ret)
+		return ret;
+
+	ret = regmap_field_write(i2c->fields[F_SDA_OUT_SEL], chan->sda_num);
+	if (ret)
+		return ret;
+
+	i2c->sda_num = chan->sda_num;
+	return 0;
+}
+
+static int rtl9300_i2c_read(struct rtl9300_i2c *i2c, u8 *buf, u8 len)
+{
+	u32 vals[4] = {};
+	int i, ret;
+
+	if (len > 16)
+		return -EIO;
+
+	ret = regmap_bulk_read(i2c->regmap, i2c->data_reg, vals, ARRAY_SIZE(vals));
+	if (ret)
+		return ret;
+
+	for (i = 0; i < len; i++) {
+		buf[i] = vals[i/4] & 0xff;
+		vals[i/4] >>= 8;
+	}
+
+	return 0;
+}
+
+static int rtl9300_i2c_write(struct rtl9300_i2c *i2c, u8 *buf, u8 len)
+{
+	u32 vals[4] = {};
+	int i;
+
+	if (len > 16)
+		return -EIO;
+
+	for (i = 0; i < len; i++) {
+		unsigned int shift = (i % 4) * 8;
+		unsigned int reg = i / 4;
+
+		vals[reg] |= buf[i] << shift;
+	}
+
+	return regmap_bulk_write(i2c->regmap, i2c->data_reg, vals, ARRAY_SIZE(vals));
+}
+
+static int rtl9300_i2c_writel(struct rtl9300_i2c *i2c, u32 data)
+{
+	return regmap_write(i2c->regmap, i2c->data_reg, data);
+}
+
+static int rtl9300_i2c_prepare_xfer(struct rtl9300_i2c *i2c, struct rtl9300_i2c_xfer *xfer)
+{
+	int ret;
+
+	if (xfer->data_len < 1 || xfer->data_len > 16)
+		return -EINVAL;
+
+	ret = regmap_field_write(i2c->fields[F_DEV_ADDR], xfer->dev_addr);
+	if (ret)
+		return ret;
+
+	ret = rtl9300_i2c_reg_addr_set(i2c, xfer->reg_addr, xfer->reg_addr_len);
+	if (ret)
+		return ret;
+
+	ret = regmap_field_write(i2c->fields[F_RWOP], xfer->write);
+	if (ret)
+		return ret;
+
+	ret = regmap_field_write(i2c->fields[F_DATA_WIDTH], (xfer->data_len - 1) & 0xf);
+	if (ret)
+		return ret;
+
+	if (xfer->write) {
+		switch (xfer->type) {
+		case RTL9300_I2C_XFER_BYTE:
+			ret = rtl9300_i2c_writel(i2c, *xfer->data);
+			break;
+		case RTL9300_I2C_XFER_WORD:
+			ret = rtl9300_i2c_writel(i2c, get_unaligned((const u16 *)xfer->data));
+			break;
+		default:
+			ret = rtl9300_i2c_write(i2c, xfer->data, xfer->data_len);
+			break;
+		}
+	}
+
+	return ret;
+}
+
+static int rtl9300_i2c_do_xfer(struct rtl9300_i2c *i2c, struct rtl9300_i2c_xfer *xfer)
+{
+	u32 val;
+	int ret;
+
+	ret = regmap_field_write(i2c->fields[F_I2C_TRIG], 1);
+	if (ret)
+		return ret;
+
+	ret = regmap_field_read_poll_timeout(i2c->fields[F_I2C_TRIG], val, !val, 100, 100000);
+	if (ret)
+		return ret;
+
+	ret = regmap_field_read(i2c->fields[F_I2C_FAIL], &val);
+	if (ret)
+		return ret;
+	if (val)
+		return -EIO;
+
+	if (!xfer->write) {
+		switch (xfer->type) {
+		case RTL9300_I2C_XFER_BYTE:
+			ret = regmap_read(i2c->regmap, i2c->data_reg, &val);
+			if (ret)
+				return ret;
+
+			*xfer->data = val & 0xff;
+			break;
+		case RTL9300_I2C_XFER_WORD:
+			ret = regmap_read(i2c->regmap, i2c->data_reg, &val);
+			if (ret)
+				return ret;
+
+			put_unaligned(val & 0xffff, (u16*)xfer->data);
+			break;
+		default:
+			ret = rtl9300_i2c_read(i2c, xfer->data, xfer->data_len);
+			if (ret)
+				return ret;
+			break;
+		}
+	}
+
+	return 0;
+}
+
+static int rtl9300_i2c_smbus_xfer(struct i2c_adapter *adap, u16 addr, unsigned short flags,
+				  char read_write, u8 command, int size,
+				  union i2c_smbus_data *data)
+{
+	struct rtl9300_i2c_chan *chan = i2c_get_adapdata(adap);
+	struct rtl9300_i2c *i2c = chan->i2c;
+	struct rtl9300_i2c_xfer xfer = {0};
+	int ret;
+
+	if (addr > 0x7f)
+		return -EINVAL;
+
+	guard(rtl9300_i2c)(i2c);
+
+	ret = rtl9300_i2c_config_chan(i2c, chan);
+	if (ret)
+		return ret;
+
+	xfer.dev_addr = addr & 0x7f;
+	xfer.write = (read_write == I2C_SMBUS_WRITE);
+	xfer.reg_addr = command;
+	xfer.reg_addr_len = 1;
+
+	switch (size) {
+	case I2C_SMBUS_BYTE:
+		xfer.data = (read_write == I2C_SMBUS_READ) ? &data->byte : &command;
+		xfer.data_len = 1;
+		xfer.reg_addr = 0;
+		xfer.reg_addr_len = 0;
+		xfer.type = RTL9300_I2C_XFER_BYTE;
+		break;
+	case I2C_SMBUS_BYTE_DATA:
+		xfer.data = &data->byte;
+		xfer.data_len = 1;
+		xfer.type = RTL9300_I2C_XFER_BYTE;
+		break;
+	case I2C_SMBUS_WORD_DATA:
+		xfer.data = (u8 *)&data->word;
+		xfer.data_len = 2;
+		xfer.type = RTL9300_I2C_XFER_WORD;
+		break;
+	case I2C_SMBUS_BLOCK_DATA:
+		xfer.data = &data->block[0];
+		xfer.data_len = data->block[0] + 1;
+		xfer.type = RTL9300_I2C_XFER_BLOCK;
+		break;
+	case I2C_SMBUS_I2C_BLOCK_DATA:
+		xfer.data = &data->block[1];
+		xfer.data_len = data->block[0];
+		xfer.type = RTL9300_I2C_XFER_BLOCK;
+		break;
+	default:
+		dev_err(&adap->dev, "Unsupported transaction %d\n", size);
+		return -EOPNOTSUPP;
+	}
+
+	ret = rtl9300_i2c_prepare_xfer(i2c, &xfer);
+	if (ret)
+		return ret;
+
+	return rtl9300_i2c_do_xfer(i2c, &xfer);
+}
+
+static u32 rtl9300_i2c_func(struct i2c_adapter *a)
+{
+	return I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA |
+	       I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_DATA |
+	       I2C_FUNC_SMBUS_I2C_BLOCK;
+}
+
+static const struct i2c_algorithm rtl9300_i2c_algo = {
+	.smbus_xfer	= rtl9300_i2c_smbus_xfer,
+	.functionality	= rtl9300_i2c_func,
+};
+
+static struct i2c_adapter_quirks rtl9300_i2c_quirks = {
+	.flags		= I2C_AQ_NO_CLK_STRETCH | I2C_AQ_NO_ZERO_LEN,
+	.max_read_len	= 16,
+	.max_write_len	= 16,
+};
+
+static int rtl9300_i2c_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rtl9300_i2c *i2c;
+	struct fwnode_handle *child;
+	struct rtl9300_i2c_drv_data *drv_data;
+	struct reg_field fields[F_NUM_FIELDS];
+	u32 clock_freq, scl_num, sda_num;
+	int ret, i = 0;
+
+	i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL);
+	if (!i2c)
+		return -ENOMEM;
+
+	i2c->regmap = syscon_node_to_regmap(dev->parent->of_node);
+	if (IS_ERR(i2c->regmap))
+		return PTR_ERR(i2c->regmap);
+	i2c->dev = dev;
+
+	mutex_init(&i2c->lock);
+
+	ret = device_property_read_u32(dev, "reg", &i2c->reg_base);
+	if (ret)
+		return ret;
+
+	ret = device_property_read_u32(dev, "realtek,scl", &scl_num);
+	if (ret || scl_num != 1)
+		scl_num = 0;
+	i2c->scl_num = (u8)scl_num;
+
+	platform_set_drvdata(pdev, i2c);
+
+	drv_data = (struct rtl9300_i2c_drv_data *)device_get_match_data(i2c->dev);
+	if (device_get_child_node_count(dev) > drv_data->max_nchan)
+		return dev_err_probe(dev, -EINVAL, "Too many channels\n");
+
+	i2c->data_reg = i2c->reg_base + drv_data->data_reg;
+	for (i = 0; i < F_NUM_FIELDS; i++) {
+		fields[i] = drv_data->field_desc[i].field;
+		if (drv_data->field_desc[i].scope == REG_SCOPE_MASTER)
+			fields[i].reg += i2c->reg_base;
+	}
+	ret = devm_regmap_field_bulk_alloc(dev, i2c->regmap, i2c->fields,
+					   fields, F_NUM_FIELDS);
+	if (ret)
+		return ret;
+
+	i = 0;
+	device_for_each_child_node(dev, child) {
+		struct rtl9300_i2c_chan *chan = &i2c->chans[i];
+		struct i2c_adapter *adap = &chan->adap;
+
+		ret = fwnode_property_read_u32(child, "reg", &sda_num);
+		if (ret)
+			return ret;
+
+		ret = fwnode_property_read_u32(child, "clock-frequency", &clock_freq);
+		if (ret)
+			clock_freq = I2C_MAX_STANDARD_MODE_FREQ;
+
+		switch (clock_freq) {
+		case I2C_MAX_STANDARD_MODE_FREQ:
+			chan->bus_freq = RTL9300_I2C_STD_FREQ;
+			break;
+		case I2C_MAX_FAST_MODE_FREQ:
+			chan->bus_freq = RTL9300_I2C_FAST_FREQ;
+			break;
+		default:
+			dev_warn(i2c->dev, "SDA%d clock-frequency %d not supported using default\n",
+				 sda_num, clock_freq);
+			break;
+		}
+
+		chan->sda_num = sda_num;
+		chan->i2c = i2c;
+		adap = &i2c->chans[i].adap;
+		adap->owner = THIS_MODULE;
+		adap->algo = &rtl9300_i2c_algo;
+		adap->quirks = &rtl9300_i2c_quirks;
+		adap->retries = 3;
+		adap->dev.parent = dev;
+		i2c_set_adapdata(adap, chan);
+		adap->dev.of_node = to_of_node(child);
+		snprintf(adap->name, sizeof(adap->name), "%s SDA%d\n", dev_name(dev), sda_num);
+		i++;
+
+		ret = devm_i2c_add_adapter(dev, adap);
+		if (ret)
+			return ret;
+	}
+	i2c->sda_num = 0xff;
+
+	/* only use standard read format */
+	ret = regmap_field_write(i2c->fields[F_RD_MODE], 0);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+#define GLB_REG_FIELD(reg, msb, lsb)    \
+	{ .field = REG_FIELD(reg, msb, lsb), .scope = REG_SCOPE_GLOBAL }
+#define MST_REG_FIELD(reg, msb, lsb)    \
+	{ .field = REG_FIELD(reg, msb, lsb), .scope = REG_SCOPE_MASTER }
+
+static const struct rtl9300_i2c_drv_data rtl9300_i2c_drv_data = {
+	.field_desc = {
+		[F_MEM_ADDR]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL1, 8, 31),
+		[F_SDA_OUT_SEL]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL1, 4, 6),
+		[F_SCL_SEL]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL1, 3, 3),
+		[F_RWOP]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL1, 2, 2),
+		[F_I2C_FAIL]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL1, 1, 1),
+		[F_I2C_TRIG]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL1, 0, 0),
+		[F_RD_MODE]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL2, 15, 15),
+		[F_DEV_ADDR]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL2, 8, 14),
+		[F_DATA_WIDTH]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL2, 4, 7),
+		[F_MEM_ADDR_WIDTH]	= MST_REG_FIELD(RTL9300_I2C_MST_CTRL2, 2, 3),
+		[F_SCL_FREQ]		= MST_REG_FIELD(RTL9300_I2C_MST_CTRL2, 0, 1),
+		[F_SDA_SEL]		= GLB_REG_FIELD(RTL9300_I2C_MST_GLB_CTRL, 0, 7),
+	},
+	.select_scl = rtl9300_i2c_select_scl,
+	.data_reg = RTL9300_I2C_MST_DATA_WORD0,
+	.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 },
+	{ .compatible = "realtek,rtl9311-i2c", .data = (void *) &rtl9310_i2c_drv_data },
+	{ .compatible = "realtek,rtl9312-i2c", .data = (void *) &rtl9310_i2c_drv_data },
+	{ .compatible = "realtek,rtl9313-i2c", .data = (void *) &rtl9310_i2c_drv_data },
+	{}
+};
+MODULE_DEVICE_TABLE(of, i2c_rtl9300_dt_ids);
+
+static struct platform_driver rtl9300_i2c_driver = {
+	.probe = rtl9300_i2c_probe,
+	.driver = {
+		.name = "i2c-rtl9300",
+		.of_match_table = i2c_rtl9300_dt_ids,
+	},
+};
+
+module_platform_driver(rtl9300_i2c_driver);
+
+MODULE_DESCRIPTION("RTL9300 I2C controller driver");
+MODULE_LICENSE("GPL");