[PATCH net-next v4 06/11] net: dsa: realtek: add new mdio interface for drivers

Luiz Angelo Daros de Luca
2022-01-05T03:16:07Z

This driver is a mdio_driver instead of a platform driver (like
realtek-smi).

Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>
Tested-by: Arınç ÜNAL <arinc.unal@arinc9.com>
---
drivers/net/dsa/realtek/Kconfig | 11 +-
drivers/net/dsa/realtek/Makefile | 1 +
drivers/net/dsa/realtek/realtek-mdio.c | 221 +++++++++++++++++++++++++
drivers/net/dsa/realtek/realtek.h | 2 +
4 files changed, 233 insertions(+), 2 deletions(-)
create mode 100644 drivers/net/dsa/realtek/realtek-mdio.c

diff --git a/drivers/net/dsa/realtek/Kconfig b/drivers/net/dsa/realtek/Kconfig
index cd1aa95b7bf0..73b26171fade 100644
--- a/drivers/net/dsa/realtek/Kconfig
+++ b/drivers/net/dsa/realtek/Kconfig
@@ -9,6 +9,13 @@ menuconfig NET_DSA_REALTEK
help
Select to enable support for Realtek Ethernet switch chips.

+config NET_DSA_REALTEK_MDIO
+ tristate "Realtek MDIO connected switch driver"
+ depends on NET_DSA_REALTEK
+ default y
+ help
+ Select to enable support for registering switches configured
+ through MDIO.
config NET_DSA_REALTEK_SMI
tristate "Realtek SMI connected switch driver"
depends on NET_DSA_REALTEK
@@ -21,7 +28,7 @@ config NET_DSA_REALTEK_RTL8365MB
tristate "Realtek RTL8365MB switch subdriver"
default y
depends on NET_DSA_REALTEK
- depends on NET_DSA_REALTEK_SMI
+ depends on NET_DSA_REALTEK_SMI || NET_DSA_REALTEK_MDIO
select NET_DSA_TAG_RTL8_4
help
Select to enable support for Realtek RTL8365MB
@@ -30,7 +37,7 @@ config NET_DSA_REALTEK_RTL8366RB
tristate "Realtek RTL8366RB switch subdriver"
default y
depends on NET_DSA_REALTEK
- depends on NET_DSA_REALTEK_SMI
+ depends on NET_DSA_REALTEK_SMI || NET_DSA_REALTEK_MDIO
select NET_DSA_TAG_RTL4_A
help
Select to enable support for Realtek RTL8366RB
diff --git a/drivers/net/dsa/realtek/Makefile b/drivers/net/dsa/realtek/Makefile
index 8b5a4abcedd3..0aab57252a7c 100644
--- a/drivers/net/dsa/realtek/Makefile
+++ b/drivers/net/dsa/realtek/Makefile
@@ -1,4 +1,5 @@
# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_NET_DSA_REALTEK_MDIO) += realtek-mdio.o
obj-$(CONFIG_NET_DSA_REALTEK_SMI) += realtek-smi.o
obj-$(CONFIG_NET_DSA_REALTEK_RTL8366RB) += rtl8366.o
rtl8366-objs := rtl8366-core.o rtl8366rb.o
diff --git a/drivers/net/dsa/realtek/realtek-mdio.c b/drivers/net/dsa/realtek/realtek-mdio.c
new file mode 100644
index 000000000000..b505f4d3c5f0
--- /dev/null
+++ b/drivers/net/dsa/realtek/realtek-mdio.c
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Realtek MDIO interface driver
+ *
+ * ASICs we intend to support with this driver:
+ *
+ * RTL8366 - The original version, apparently
+ * RTL8369 - Similar enough to have the same datsheet as RTL8366
+ * RTL8366RB - Probably reads out "RTL8366 revision B", has a quite
+ * different register layout from the other two
+ * RTL8366S - Is this "RTL8366 super"?
+ * RTL8367 - Has an OpenWRT driver as well
+ * RTL8368S - Seems to be an alternative name for RTL8366RB
+ * RTL8370 - Also uses SMI
+ *
+ * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
+ * Copyright (C) 2010 Antti Seppälä <a.seppala@gmail.com>
+ * Copyright (C) 2010 Roman Yeryomin <roman@advem.lv>
+ * Copyright (C) 2011 Colin Leitner <colin.leitner@googlemail.com>
+ * Copyright (C) 2009-2010 Gabor Juhos <juhosg@openwrt.org>
+ */
+
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+
+#include "realtek.h"
+
+/* Read/write via mdiobus */
+#define REALTEK_MDIO_CTRL0_REG 31
+#define REALTEK_MDIO_START_REG 29
+#define REALTEK_MDIO_CTRL1_REG 21
+#define REALTEK_MDIO_ADDRESS_REG 23
+#define REALTEK_MDIO_DATA_WRITE_REG 24
+#define REALTEK_MDIO_DATA_READ_REG 25
+
+#define REALTEK_MDIO_START_OP 0xFFFF
+#define REALTEK_MDIO_ADDR_OP 0x000E
+#define REALTEK_MDIO_READ_OP 0x0001
+#define REALTEK_MDIO_WRITE_OP 0x0003
+
+static int realtek_mdio_read_reg(struct realtek_priv *priv, u32 addr, u32 *data)
+{
+ u32 phy_id = priv->phy_id;
+ struct mii_bus *bus = priv->bus;
+
+ mutex_lock(&bus->mdio_lock);
+
+ bus->write(bus, phy_id, REALTEK_MDIO_CTRL0_REG, REALTEK_MDIO_ADDR_OP);
+ bus->write(bus, phy_id, REALTEK_MDIO_START_REG, REALTEK_MDIO_START_OP);
+ bus->write(bus, phy_id, REALTEK_MDIO_ADDRESS_REG, addr);
+ bus->write(bus, phy_id, REALTEK_MDIO_START_REG, REALTEK_MDIO_START_OP);
+ bus->write(bus, phy_id, REALTEK_MDIO_CTRL1_REG, REALTEK_MDIO_READ_OP);
+ bus->write(bus, phy_id, REALTEK_MDIO_START_REG, REALTEK_MDIO_START_OP);
+ *data = bus->read(bus, phy_id, REALTEK_MDIO_DATA_READ_REG);
+
+ mutex_unlock(&bus->mdio_lock);
+
+ return 0;
+}
+
+static int realtek_mdio_write_reg(struct realtek_priv *priv, u32 addr, u32 data)
+{
+ u32 phy_id = priv->phy_id;
+ struct mii_bus *bus = priv->bus;
+
+ mutex_lock(&bus->mdio_lock);
+
+ bus->write(bus, phy_id, REALTEK_MDIO_CTRL0_REG, REALTEK_MDIO_ADDR_OP);
+ bus->write(bus, phy_id, REALTEK_MDIO_START_REG, REALTEK_MDIO_START_OP);
+ bus->write(bus, phy_id, REALTEK_MDIO_ADDRESS_REG, addr);
+ bus->write(bus, phy_id, REALTEK_MDIO_START_REG, REALTEK_MDIO_START_OP);
+ bus->write(bus, phy_id, REALTEK_MDIO_DATA_WRITE_REG, data);
+ bus->write(bus, phy_id, REALTEK_MDIO_START_REG, REALTEK_MDIO_START_OP);
+ bus->write(bus, phy_id, REALTEK_MDIO_CTRL1_REG, REALTEK_MDIO_WRITE_OP);
+
+ mutex_unlock(&bus->mdio_lock);
+
+ return 0;
+}
+
+/* Regmap accessors */
+
+static int realtek_mdio_write(void *ctx, u32 reg, u32 val)
+{
+ struct realtek_priv *priv = ctx;
+
+ return realtek_mdio_write_reg(priv, reg, val);
+}
+
+static int realtek_mdio_read(void *ctx, u32 reg, u32 *val)
+{
+ struct realtek_priv *priv = ctx;
+
+ return realtek_mdio_read_reg(priv, reg, val);
+}
+
+static const struct regmap_config realtek_mdio_regmap_config = {
+ .reg_bits = 10, /* A4..A0 R4..R0 */
+ .val_bits = 16,
+ .reg_stride = 1,
+ /* PHY regs are at 0x8000 */
+ .max_register = 0xffff,
+ .reg_format_endian = REGMAP_ENDIAN_BIG,
+ .reg_read = realtek_mdio_read,
+ .reg_write = realtek_mdio_write,
+ .cache_type = REGCACHE_NONE,
+};
+
+static int realtek_mdio_probe(struct mdio_device *mdiodev)
+{
+ struct realtek_priv *priv;
+ struct device *dev = &mdiodev->dev;
+ const struct realtek_variant *var;
+ int ret;
+ struct device_node *np;
+
+ var = of_device_get_match_data(dev);
+ priv = devm_kzalloc(&mdiodev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->map = devm_regmap_init(dev, NULL, priv, &realtek_mdio_regmap_config);
+ if (IS_ERR(priv->map)) {
+ ret = PTR_ERR(priv->map);
+ dev_err(dev, "regmap init failed: %d\n", ret);
+ return ret;
+ }
+
+ priv->phy_id = mdiodev->addr;
+ priv->bus = mdiodev->bus;
+ priv->dev = &mdiodev->dev;
+ priv->chip_data = (void *)priv + sizeof(*priv);
+
+ priv->clk_delay = var->clk_delay;
+ priv->cmd_read = var->cmd_read;
+ priv->cmd_write = var->cmd_write;
+ priv->ops = var->ops;
+
+ priv->write_reg_noack = realtek_mdio_write_reg;
+
+ np = dev->of_node;
+
+ dev_set_drvdata(dev, priv);
+
+ /* TODO: if power is software controlled, set up any regulators here */
+ priv->leds_disabled = of_property_read_bool(np, "realtek,disable-leds");
+
+ ret = priv->ops->detect(priv);
+ if (ret) {
+ dev_err(dev, "unable to detect switch\n");
+ return ret;
+ }
+
+ priv->ds = devm_kzalloc(dev, sizeof(*priv->ds), GFP_KERNEL);
+ if (!priv->ds)
+ return -ENOMEM;
+
+ priv->ds->dev = dev;
+ priv->ds->num_ports = priv->num_ports;
+ priv->ds->priv = priv;
+ priv->ds->ops = var->ds_ops;
+
+ ret = dsa_register_switch(priv->ds);
+ if (ret) {
+ dev_err(priv->dev, "unable to register switch ret = %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void realtek_mdio_remove(struct mdio_device *mdiodev)
+{
+ struct realtek_priv *priv = dev_get_drvdata(&mdiodev->dev);
+
+ if (!priv)
+ return;
+
+ dsa_unregister_switch(priv->ds);
+
+ dev_set_drvdata(&mdiodev->dev, NULL);
+}
+
+static void realtek_mdio_shutdown(struct mdio_device *mdiodev)
+{
+ struct realtek_priv *priv = dev_get_drvdata(&mdiodev->dev);
+
+ if (!priv)
+ return;
+
+ dsa_switch_shutdown(priv->ds);
+
+ dev_set_drvdata(&mdiodev->dev, NULL);
+}
+
+static const struct of_device_id realtek_mdio_of_match[] = {
+#if IS_ENABLED(CONFIG_NET_DSA_REALTEK_RTL8366RB)
+ { .compatible = "realtek,rtl8366rb", .data = &rtl8366rb_variant, },
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_REALTEK_RTL8365MB)
+ { .compatible = "realtek,rtl8365mb", .data = &rtl8365mb_variant, },
+#endif
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, realtek_mdio_of_match);
+
+static struct mdio_driver realtek_mdio_driver = {
+ .mdiodrv.driver = {
+ .name = "realtek-mdio",
+ .of_match_table = of_match_ptr(realtek_mdio_of_match),
+ },
+ .probe = realtek_mdio_probe,
+ .remove = realtek_mdio_remove,
+ .shutdown = realtek_mdio_shutdown,
+};
+
+mdio_module_driver(realtek_mdio_driver);
+
+MODULE_AUTHOR("Luiz Angelo Daros de Luca <luizluca@gmail.com>");
+MODULE_DESCRIPTION("Driver for Realtek ethernet switch connected via MDIO interface");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/dsa/realtek/realtek.h b/drivers/net/dsa/realtek/realtek.h
index a03de15c4a94..97274273cb3b 100644
--- a/drivers/net/dsa/realtek/realtek.h
+++ b/drivers/net/dsa/realtek/realtek.h
@@ -50,6 +50,8 @@ struct realtek_priv {
struct gpio_desc *mdio;
struct regmap *map;
struct mii_bus *slave_mii_bus;
+ struct mii_bus *bus;
+ int phy_id;

unsigned int clk_delay;
u8 cmd_read;
--
2.34.0