[PATCH net-next v9 4/9] net: txgbe: Register I2C platform device

[Jiawen Wu <jiawenwu@xxxxxxxxxxxxxx>]

Register the platform device to use Designware I2C bus master driver.
Use regmap to read/write I2C device region from given base offset.

Signed-off-by: Jiawen Wu <jiawenwu@xxxxxxxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Reviewed-by: Piotr Raczynski <piotr.raczynski@xxxxxxxxx>
---
 drivers/net/ethernet/wangxun/Kconfig          |  2 +
 .../net/ethernet/wangxun/txgbe/txgbe_phy.c    | 70 +++++++++++++++++++
 .../net/ethernet/wangxun/txgbe/txgbe_type.h   |  4 ++
 3 files changed, 76 insertions(+)

diff --git a/drivers/net/ethernet/wangxun/Kconfig b/drivers/net/ethernet/wangxun/Kconfig
index a62614eeed2e..ec058a72afb6 100644
--- a/drivers/net/ethernet/wangxun/Kconfig
+++ b/drivers/net/ethernet/wangxun/Kconfig
@@ -40,6 +40,8 @@ config NGBE
 config TXGBE
 	tristate "Wangxun(R) 10GbE PCI Express adapters support"
 	depends on PCI
+	select I2C_DESIGNWARE_PLATFORM
+	select REGMAP
 	select COMMON_CLK
 	select LIBWX
 	help
diff --git a/drivers/net/ethernet/wangxun/txgbe/txgbe_phy.c b/drivers/net/ethernet/wangxun/txgbe/txgbe_phy.c
index 06506cfb8d06..6ea33e753df4 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_phy.c
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_phy.c
@@ -1,9 +1,11 @@
 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) 2015 - 2023 Beijing WangXun Technology Co., Ltd. */
 
+#include <linux/platform_device.h>
 #include <linux/gpio/property.h>
 #include <linux/clk-provider.h>
 #include <linux/clkdev.h>
+#include <linux/regmap.h>
 #include <linux/i2c.h>
 #include <linux/pci.h>
 
@@ -98,6 +100,64 @@ static int txgbe_clock_register(struct txgbe *txgbe)
 	return 0;
 }
 
+static int txgbe_i2c_read(void *context, unsigned int reg, unsigned int *val)
+{
+	struct wx *wx = context;
+
+	*val = rd32(wx, reg + TXGBE_I2C_BASE);
+
+	return 0;
+}
+
+static int txgbe_i2c_write(void *context, unsigned int reg, unsigned int val)
+{
+	struct wx *wx = context;
+
+	wr32(wx, reg + TXGBE_I2C_BASE, val);
+
+	return 0;
+}
+
+static const struct regmap_config i2c_regmap_config = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_read = txgbe_i2c_read,
+	.reg_write = txgbe_i2c_write,
+	.fast_io = true,
+};
+
+static int txgbe_i2c_register(struct txgbe *txgbe)
+{
+	struct platform_device_info info = {};
+	struct platform_device *i2c_dev;
+	struct regmap *i2c_regmap;
+	struct pci_dev *pdev;
+	struct wx *wx;
+
+	wx = txgbe->wx;
+	pdev = wx->pdev;
+	i2c_regmap = devm_regmap_init(&pdev->dev, NULL, wx, &i2c_regmap_config);
+	if (IS_ERR(i2c_regmap)) {
+		wx_err(wx, "failed to init I2C regmap\n");
+		return PTR_ERR(i2c_regmap);
+	}
+
+	info.parent = &pdev->dev;
+	info.fwnode = software_node_fwnode(txgbe->nodes.group[SWNODE_I2C]);
+	info.name = "i2c_designware";
+	info.id = (pdev->bus->number << 8) | pdev->devfn;
+
+	info.res = &DEFINE_RES_IRQ(pdev->irq);
+	info.num_res = 1;
+	i2c_dev = platform_device_register_full(&info);
+	if (IS_ERR(i2c_dev))
+		return PTR_ERR(i2c_dev);
+
+	txgbe->i2c_dev = i2c_dev;
+
+	return 0;
+}
+
 int txgbe_init_phy(struct txgbe *txgbe)
 {
 	int ret;
@@ -114,8 +174,17 @@ int txgbe_init_phy(struct txgbe *txgbe)
 		goto err_unregister_swnode;
 	}
 
+	ret = txgbe_i2c_register(txgbe);
+	if (ret) {
+		wx_err(txgbe->wx, "failed to init i2c interface: %d\n", ret);
+		goto err_unregister_clk;
+	}
+
 	return 0;
 
+err_unregister_clk:
+	clkdev_drop(txgbe->clock);
+	clk_unregister(txgbe->clk);
 err_unregister_swnode:
 	software_node_unregister_node_group(txgbe->nodes.group);
 
@@ -124,6 +193,7 @@ int txgbe_init_phy(struct txgbe *txgbe)
 
 void txgbe_remove_phy(struct txgbe *txgbe)
 {
+	platform_device_unregister(txgbe->i2c_dev);
 	clkdev_drop(txgbe->clock);
 	clk_unregister(txgbe->clk);
 	software_node_unregister_node_group(txgbe->nodes.group);
diff --git a/drivers/net/ethernet/wangxun/txgbe/txgbe_type.h b/drivers/net/ethernet/wangxun/txgbe/txgbe_type.h
index cdbc4b37f832..55979abf01f2 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_type.h
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_type.h
@@ -55,6 +55,9 @@
 #define TXGBE_TS_CTL                            0x10300
 #define TXGBE_TS_CTL_EVAL_MD                    BIT(31)
 
+/* I2C registers */
+#define TXGBE_I2C_BASE                          0x14900
+
 /* Part Number String Length */
 #define TXGBE_PBANUM_LENGTH                     32
 
@@ -146,6 +149,7 @@ struct txgbe_nodes {
 struct txgbe {
 	struct wx *wx;
 	struct txgbe_nodes nodes;
+	struct platform_device *i2c_dev;
 	struct clk_lookup *clock;
 	struct clk *clk;
 };
-- 
2.27.0