--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include "i2c-rtl9300.h"
+
+#define REG(x) (i2c->base + x + (i2c->scl_num ? i2c->mst2_offset : 0))
+#define REG_MASK(clear, set, reg) \
+ writel((readl(REG(reg)) & ~(clear)) | (set), REG(reg))
+
+struct i2c_drv_data {
+ int scl0_pin;
+ int scl1_pin;
+ int sda0_pin;
+ struct i2c_algorithm *algo;
+ int (*read)(struct rtl9300_i2c *i2c, u8 *buf, int len);
+ int (*write)(struct rtl9300_i2c *i2c, u8 *buf, int len);
+ void (*reg_addr_set)(struct rtl9300_i2c *i2c, u32 reg, u16 len);
+ int (*config_xfer)(struct rtl9300_i2c *i2c, u16 addr, u16 len);
+ int (*execute_xfer)(struct rtl9300_i2c *i2c, char read_write, int size,
+ union i2c_smbus_data * data, int len);
+ void (*writel)(struct rtl9300_i2c *i2c, u32 data);
+ void (*config_io)(struct rtl9300_i2c *i2c, int scl_num, int sda_num);
+ u32 mst2_offset;
+};
+
+DEFINE_MUTEX(i2c_lock);
+
+static void rtl9300_i2c_reg_addr_set(struct rtl9300_i2c *i2c, u32 reg, u16 len)
+{
+ // Set register address width
+ REG_MASK(0x3 << RTL9300_I2C_CTRL2_MADDR_WIDTH, len << RTL9300_I2C_CTRL2_MADDR_WIDTH,
+ RTL9300_I2C_CTRL2);
+
+ // Set register address
+ REG_MASK(0xffffff << RTL9300_I2C_CTRL1_MEM_ADDR, reg << RTL9300_I2C_CTRL1_MEM_ADDR,
+ RTL9300_I2C_CTRL1);
+}
+
+static void rtl9310_i2c_reg_addr_set(struct rtl9300_i2c *i2c, u32 reg, u16 len)
+{
+ // Set register address width
+ REG_MASK(0x3 << RTL9310_I2C_CTRL_MADDR_WIDTH, len << RTL9310_I2C_CTRL_MADDR_WIDTH,
+ RTL9310_I2C_CTRL);
+
+ // Set register address
+ writel(reg, REG(RTL9310_I2C_MEMADDR));
+}
+
+static void rtl9300_i2c_config_io(struct rtl9300_i2c *i2c, int scl_num, int sda_num)
+{
+ u32 v;
+
+ // Set SCL pin
+ REG_MASK(0, BIT(RTL9300_I2C_CTRL1_GPIO8_SCL_SEL), RTL9300_I2C_CTRL1);
+
+ // Set SDA pin
+ REG_MASK(0x7 << RTL9300_I2C_CTRL1_SDA_OUT_SEL,
+ i2c->sda_num << RTL9300_I2C_CTRL1_SDA_OUT_SEL, RTL9300_I2C_CTRL1);
+
+ // Set SDA pin to I2C functionality
+ v = readl(i2c->base + RTL9300_I2C_MST_GLB_CTRL);
+ v |= BIT(i2c->sda_num);
+ writel(v, i2c->base + RTL9300_I2C_MST_GLB_CTRL);
+}
+
+static void rtl9310_i2c_config_io(struct rtl9300_i2c *i2c, int scl_num, int sda_num)
+{
+ u32 v;
+
+ // Set SCL pin
+ REG_MASK(0, BIT(RTL9310_I2C_MST_IF_SEL_GPIO_SCL_SEL + scl_num), RTL9310_I2C_MST_IF_SEL);
+
+ // Set SDA pin
+ REG_MASK(0x7 << RTL9310_I2C_CTRL_SDA_OUT_SEL,
+ i2c->sda_num << RTL9310_I2C_CTRL_SDA_OUT_SEL, RTL9310_I2C_CTRL);
+
+ // Set SDA pin to I2C functionality
+ v = readl(i2c->base + RTL9310_I2C_MST_IF_SEL);
+ v |= BIT(i2c->sda_num);
+ writel(v, i2c->base + RTL9310_I2C_MST_IF_SEL);
+}
+
+static int rtl9300_i2c_config_xfer(struct rtl9300_i2c *i2c, u16 addr, u16 len)
+{
+ // Set bus frequency
+ REG_MASK(0x3 << RTL9300_I2C_CTRL2_SCL_FREQ,
+ i2c->bus_freq << RTL9300_I2C_CTRL2_SCL_FREQ, RTL9300_I2C_CTRL2);
+
+ // Set slave device address
+ REG_MASK(0x7f << RTL9300_I2C_CTRL2_DEV_ADDR,
+ addr << RTL9300_I2C_CTRL2_DEV_ADDR, RTL9300_I2C_CTRL2);
+
+ // Set data length
+ REG_MASK(0xf << RTL9300_I2C_CTRL2_DATA_WIDTH,
+ ((len - 1) & 0xf) << RTL9300_I2C_CTRL2_DATA_WIDTH, RTL9300_I2C_CTRL2);
+
+ // Set read mode to random
+ REG_MASK(0x1 << RTL9300_I2C_CTRL2_READ_MODE, 0, RTL9300_I2C_CTRL2);
+
+ return 0;
+}
+
+static int rtl9310_i2c_config_xfer(struct rtl9300_i2c *i2c, u16 addr, u16 len)
+{
+ // Set bus frequency
+ REG_MASK(0x3 << RTL9310_I2C_CTRL_SCL_FREQ,
+ i2c->bus_freq << RTL9310_I2C_CTRL_SCL_FREQ, RTL9310_I2C_CTRL);
+
+ // Set slave device address
+ REG_MASK(0x7f << RTL9310_I2C_CTRL_DEV_ADDR,
+ addr << RTL9310_I2C_CTRL_DEV_ADDR, RTL9310_I2C_CTRL);
+
+ // Set data length
+ REG_MASK(0xf << RTL9310_I2C_CTRL_DATA_WIDTH,
+ ((len - 1) & 0xf) << RTL9310_I2C_CTRL_DATA_WIDTH, RTL9310_I2C_CTRL);
+
+ // Set read mode to random
+ REG_MASK(0x1 << RTL9310_I2C_CTRL_READ_MODE, 0, RTL9310_I2C_CTRL);
+
+ return 0;
+}
+
+static int i2c_read(void __iomem *r0, u8 *buf, int len)
+{
+ int i;
+ u32 v;
+
+ if (len > 16)
+ return -EIO;
+
+ for (i = 0; i < len; i++) {
+ if (i % 4 == 0)
+ v = readl(r0 + i);
+ buf[i] = v;
+ v >>= 8;
+ }
+
+ return len;
+}
+
+static int i2c_write(void __iomem *r0, u8 *buf, int len)
+{
+ u32 v;
+ int i;
+
+ if (len > 16)
+ return -EIO;
+
+ for (i = 0; i < len; i++) {
+ if (! (i % 4))
+ v = 0;
+ v <<= 8;
+ v |= buf[i];
+ if (i % 4 == 3 || i == len - 1)
+ writel(v, r0 + (i / 4) * 4);
+ }
+
+ return len;
+}
+
+static int rtl9300_i2c_read(struct rtl9300_i2c *i2c, u8 *buf, int len)
+{
+ return i2c_read(REG(RTL9300_I2C_DATA_WORD0), buf, len);
+}
+
+static int rtl9300_i2c_write(struct rtl9300_i2c *i2c, u8 *buf, int len)
+{
+ return i2c_write(REG(RTL9300_I2C_DATA_WORD0), buf, len);
+}
+
+static int rtl9310_i2c_read(struct rtl9300_i2c *i2c, u8 *buf, int len)
+{
+ return i2c_read(REG(RTL9310_I2C_DATA), buf, len);
+}
+
+static int rtl9310_i2c_write(struct rtl9300_i2c *i2c, u8 *buf, int len)
+{
+ return i2c_write(REG(RTL9310_I2C_DATA), buf, len);
+}
+
+static void rtl9300_writel(struct rtl9300_i2c *i2c, u32 data)
+{
+ writel(data, REG(RTL9300_I2C_DATA_WORD0));
+}
+
+static void rtl9310_writel(struct rtl9300_i2c *i2c, u32 data)
+{
+ writel(data, REG(RTL9310_I2C_DATA));
+}
+
+
+static int rtl9300_execute_xfer(struct rtl9300_i2c *i2c, char read_write,
+ int size, union i2c_smbus_data * data, int len)
+{
+ u32 v;
+
+ if (read_write == I2C_SMBUS_READ)
+ REG_MASK(BIT(RTL9300_I2C_CTRL1_RWOP), 0, RTL9300_I2C_CTRL1);
+ else
+ REG_MASK(0, BIT(RTL9300_I2C_CTRL1_RWOP), RTL9300_I2C_CTRL1);
+
+ REG_MASK(0, BIT(RTL9300_I2C_CTRL1_I2C_TRIG), RTL9300_I2C_CTRL1);
+ do {
+ v = readl(REG(RTL9300_I2C_CTRL1));
+ } while (v & BIT(RTL9300_I2C_CTRL1_I2C_TRIG));
+
+ if (v & BIT(RTL9300_I2C_CTRL1_I2C_FAIL))
+ return -EIO;
+
+ if (read_write == I2C_SMBUS_READ) {
+ if (size == I2C_SMBUS_BYTE || size == I2C_SMBUS_BYTE_DATA){
+ data->byte = readl(REG(RTL9300_I2C_DATA_WORD0));
+ } else if (size == I2C_SMBUS_WORD_DATA) {
+ data->word = readl(REG(RTL9300_I2C_DATA_WORD0));
+ } else if (len > 0) {
+ rtl9300_i2c_read(i2c, &data->block[0], len);
+ }
+ }
+
+ return 0;
+}
+
+static int rtl9310_execute_xfer(struct rtl9300_i2c *i2c, char read_write,
+ int size, union i2c_smbus_data * data, int len)
+{
+ u32 v;
+
+ if (read_write == I2C_SMBUS_READ)
+ REG_MASK(BIT(RTL9310_I2C_CTRL_RWOP), 0, RTL9310_I2C_CTRL);
+ else
+ REG_MASK(0, BIT(RTL9310_I2C_CTRL_RWOP), RTL9310_I2C_CTRL);
+
+ REG_MASK(0, BIT(RTL9310_I2C_CTRL_I2C_TRIG), RTL9310_I2C_CTRL);
+ do {
+ v = readl(REG(RTL9310_I2C_CTRL));
+ } while (v & BIT(RTL9310_I2C_CTRL_I2C_TRIG));
+
+ if (v & BIT(RTL9310_I2C_CTRL_I2C_FAIL))
+ return -EIO;
+
+ if (read_write == I2C_SMBUS_READ) {
+ if (size == I2C_SMBUS_BYTE || size == I2C_SMBUS_BYTE_DATA){
+ data->byte = readl(REG(RTL9310_I2C_DATA));
+ } else if (size == I2C_SMBUS_WORD_DATA) {
+ data->word = readl(REG(RTL9310_I2C_DATA));
+ } else if (len > 0) {
+ rtl9310_i2c_read(i2c, &data->block[0], len);
+ }
+ }
+
+ 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 *i2c = i2c_get_adapdata(adap);
+ struct i2c_drv_data *drv_data = (struct i2c_drv_data *)device_get_match_data(i2c->dev);
+ int len = 0, ret;
+
+ mutex_lock(&i2c_lock);
+ switch (size) {
+ case I2C_SMBUS_QUICK:
+ drv_data->config_xfer(i2c, addr, 0);
+ drv_data->reg_addr_set(i2c, 0, 0);
+ break;
+
+ case I2C_SMBUS_BYTE:
+ if (read_write == I2C_SMBUS_WRITE) {
+ drv_data->config_xfer(i2c, addr, 0);
+ drv_data->reg_addr_set(i2c, command, 1);
+ } else {
+ drv_data->config_xfer(i2c, addr, 1);
+ drv_data->reg_addr_set(i2c, 0, 0);
+ }
+ break;
+
+ case I2C_SMBUS_BYTE_DATA:
+ pr_debug("I2C_SMBUS_BYTE_DATA %02x, read %d cmd %02x\n", addr, read_write, command);
+ drv_data->reg_addr_set(i2c, command, 1);
+ drv_data->config_xfer(i2c, addr, 1);
+
+ if (read_write == I2C_SMBUS_WRITE) {
+ pr_debug("--> data %02x\n", data->byte);
+ drv_data->writel(i2c, data->byte);
+ }
+ break;
+
+ case I2C_SMBUS_WORD_DATA:
+ pr_debug("I2C_SMBUS_WORD %02x, read %d\n", addr, read_write);
+ drv_data->reg_addr_set(i2c, command, 1);
+ drv_data->config_xfer(i2c, addr, 2);
+ if (read_write == I2C_SMBUS_WRITE)
+ drv_data->writel(i2c, data->word);
+ break;
+
+ case I2C_SMBUS_BLOCK_DATA:
+ pr_debug("I2C_SMBUS_BLOCK_DATA %02x, read %d, len %d\n",
+ addr, read_write, data->block[0]);
+ drv_data->reg_addr_set(i2c, command, 1);
+ drv_data->config_xfer(i2c, addr, data->block[0]);
+ if (read_write == I2C_SMBUS_WRITE)
+ drv_data->write(i2c, &data->block[1], data->block[0]);
+ len = data->block[0];
+ break;
+
+ default:
+ dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
+ return -EOPNOTSUPP;
+ }
+
+ ret = drv_data->execute_xfer(i2c, read_write, size, data, len);
+
+ mutex_unlock(&i2c_lock);
+
+ return ret;
+}
+
+static u32 rtl9300_i2c_func(struct i2c_adapter *a)
+{
+ return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
+ I2C_FUNC_SMBUS_BLOCK_DATA;
+}
+
+static const struct i2c_algorithm rtl9300_i2c_algo = {
+ .smbus_xfer = rtl9300_i2c_smbus_xfer,
+ .functionality = rtl9300_i2c_func,
+};
+
+struct i2c_adapter_quirks rtl9300_i2c_quirks = {
+ .flags = I2C_AQ_NO_CLK_STRETCH,
+ .max_read_len = 16,
+ .max_write_len = 16,
+};
+
+static int rtl9300_i2c_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct rtl9300_i2c *i2c;
+ struct i2c_adapter *adap;
+ struct i2c_drv_data *drv_data;
+ struct device_node *node = pdev->dev.of_node;
+ u32 clock_freq, pin;
+ int ret = 0;
+
+ pr_info("%s probing I2C adapter\n", __func__);
+
+ if (!node) {
+ dev_err(i2c->dev, "No DT found\n");
+ return -EINVAL;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ drv_data = (struct i2c_drv_data *) device_get_match_data(&pdev->dev);
+
+ i2c = devm_kzalloc(&pdev->dev, sizeof(struct rtl9300_i2c), GFP_KERNEL);
+ if (!i2c)
+ return -ENOMEM;
+
+ i2c->base = devm_ioremap_resource(&pdev->dev, res);
+ i2c->mst2_offset = drv_data->mst2_offset;
+ if (IS_ERR(i2c->base))
+ return PTR_ERR(i2c->base);
+
+ pr_debug("%s base memory %08x\n", __func__, (u32)i2c->base);
+ i2c->dev = &pdev->dev;
+
+ if (of_property_read_u32(node, "clock-frequency", &clock_freq)) {
+ clock_freq = I2C_MAX_STANDARD_MODE_FREQ;
+ }
+ switch(clock_freq) {
+ case I2C_MAX_STANDARD_MODE_FREQ:
+ i2c->bus_freq = RTL9300_I2C_STD_FREQ;
+ break;
+
+ case I2C_MAX_FAST_MODE_FREQ:
+ i2c->bus_freq = RTL9300_I2C_FAST_FREQ;
+ break;
+ default:
+ dev_warn(i2c->dev, "clock-frequency %d not supported\n", clock_freq);
+ return -EINVAL;
+ }
+
+ dev_info(&pdev->dev, "SCL speed %d, mode is %d\n", clock_freq, i2c->bus_freq);
+
+ if (of_property_read_u32(node, "scl-pin", &pin)) {
+ dev_warn(i2c->dev, "SCL pin not found in DT, using default\n");
+ pin = drv_data->scl0_pin;
+ }
+ if (!(pin == drv_data->scl0_pin || pin == drv_data->scl1_pin)) {
+ dev_warn(i2c->dev, "SCL pin %d not supported\n", pin);
+ return -EINVAL;
+ }
+ i2c->scl_num = pin == drv_data->scl0_pin ? 0 : 1;
+ pr_info("%s scl_num %d\n", __func__, i2c->scl_num);
+
+ if (of_property_read_u32(node, "sda-pin", &pin)) {
+ dev_warn(i2c->dev, "SDA pin not found in DT, using default \n");
+ pin = drv_data->sda0_pin;
+ }
+ i2c->sda_num = pin - drv_data->sda0_pin;
+ if (i2c->sda_num < 0 || i2c->sda_num > 7) {
+ dev_warn(i2c->dev, "SDA pin %d not supported\n", pin);
+ return -EINVAL;
+ }
+ pr_info("%s sda_num %d\n", __func__, i2c->sda_num);
+
+ adap = &i2c->adap;
+ adap->owner = THIS_MODULE;
+ adap->algo = &rtl9300_i2c_algo;
+ adap->retries = 3;
+ adap->dev.parent = &pdev->dev;
+ i2c_set_adapdata(adap, i2c);
+ adap->dev.of_node = node;
+ strlcpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name));
+
+ platform_set_drvdata(pdev, i2c);
+
+ drv_data->config_io(i2c, i2c->scl_num, i2c->sda_num);
+
+ ret = i2c_add_adapter(adap);
+
+ return ret;
+}
+
+static int rtl9300_i2c_remove(struct platform_device *pdev)
+{
+ struct rtl9300_i2c *i2c = platform_get_drvdata(pdev);
+
+ i2c_del_adapter(&i2c->adap);
+
+ return 0;
+}
+
+struct i2c_drv_data rtl9300_i2c_drv_data = {
+ .scl0_pin = 8,
+ .scl1_pin = 17,
+ .sda0_pin = 9,
+ .read = rtl9300_i2c_read,
+ .read = rtl9300_i2c_write,
+ .reg_addr_set = rtl9300_i2c_reg_addr_set,
+ .config_xfer = rtl9300_i2c_config_xfer,
+ .execute_xfer = rtl9300_execute_xfer,
+ .writel = rtl9300_writel,
+ .config_io = rtl9300_i2c_config_io,
+ .mst2_offset = 0x1c,
+};
+
+struct i2c_drv_data rtl9310_i2c_drv_data = {
+ .scl0_pin = 13,
+ .scl1_pin = 14,
+ .sda0_pin = 0,
+ .read = rtl9310_i2c_read,
+ .read = rtl9310_i2c_write,
+ .reg_addr_set = rtl9310_i2c_reg_addr_set,
+ .config_xfer = rtl9310_i2c_config_xfer,
+ .execute_xfer = rtl9310_execute_xfer,
+ .writel = rtl9310_writel,
+ .config_io = rtl9310_i2c_config_io,
+ .mst2_offset = 0x18,
+};
+
+static const struct of_device_id i2c_rtl9300_dt_ids[] = {
+ { .compatible = "realtek,rtl9300-i2c", .data = (void *) &rtl9300_i2c_drv_data },
+ { .compatible = "realtek,rtl9310-i2c", .data = (void *) &rtl9310_i2c_drv_data },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rtl838x_eth_of_ids);
+
+static struct platform_driver rtl9300_i2c_driver = {
+ .probe = rtl9300_i2c_probe,
+ .remove = rtl9300_i2c_remove,
+ .driver = {
+ .name = "i2c-rtl9300",
+ .pm = NULL,
+ .of_match_table = i2c_rtl9300_dt_ids,
+ },
+};
+
+module_platform_driver(rtl9300_i2c_driver);
+
+MODULE_AUTHOR("Birger Koblitz");
+MODULE_DESCRIPTION("RTL9300 I2C host driver");
+MODULE_LICENSE("GPL v2");
projects / openwrt / openwrt.git / commitdiff