This patch adds the driver for the MDIO interface
inside of Qualcomm IPQ40xx series SoC-s.
Signed-off-by: Christian Lamparter <chunkeey@xxxxxxxxx>
Signed-off-by: Robert Marko <robert.marko@xxxxxxxxxx>
Cc: Luka Perkov <luka.perkov@xxxxxxxxxx>
---
Changes from v1 to v2:
* Remove magic default value
* Remove lockdep_assert_held
* Add C45 check
* Simplify the driver
* Drop device and mii_bus structs from private struct
* Use devm_mdiobus_alloc_size()
drivers/net/phy/Kconfig | 7 ++
drivers/net/phy/Makefile | 1 +
drivers/net/phy/mdio-ipq40xx.c | 176 +++++++++++++++++++++++++++++++++
3 files changed, 184 insertions(+)
create mode 100644 drivers/net/phy/mdio-ipq40xx.c
diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
index 3fa33d27eeba..815d52fa6080 100644
--- a/drivers/net/phy/Kconfig
+++ b/drivers/net/phy/Kconfig
@@ -157,6 +157,13 @@ config MDIO_I2C
This is library mode.
+config MDIO_IPQ40XX
+ tristate "Qualcomm IPQ40xx MDIO interface"
+ depends on HAS_IOMEM && OF
+ help
+ This driver supports the MDIO interface found in Qualcomm
+ IPQ40xx series Soc-s.
+
config MDIO_IPQ8064
tristate "Qualcomm IPQ8064 MDIO interface support"
depends on HAS_IOMEM && OF_MDIO
diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index 2f5c7093a65b..36aafc6128c4 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_MDIO_CAVIUM) += mdio-cavium.o
obj-$(CONFIG_MDIO_GPIO) += mdio-gpio.o
obj-$(CONFIG_MDIO_HISI_FEMAC) += mdio-hisi-femac.o
obj-$(CONFIG_MDIO_I2C) += mdio-i2c.o
+obj-$(CONFIG_MDIO_IPQ40XX) += mdio-ipq40xx.o
obj-$(CONFIG_MDIO_IPQ8064) += mdio-ipq8064.o
obj-$(CONFIG_MDIO_MOXART) += mdio-moxart.o
obj-$(CONFIG_MDIO_MSCC_MIIM) += mdio-mscc-miim.o
diff --git a/drivers/net/phy/mdio-ipq40xx.c b/drivers/net/phy/mdio-ipq40xx.c
new file mode 100644
index 000000000000..d8c11c621f20
--- /dev/null
+++ b/drivers/net/phy/mdio-ipq40xx.c
@@ -0,0 +1,176 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+/* Copyright (c) 2015, The Linux Foundation. All rights reserved. */
+/* Copyright (c) 2020 Sartura Ltd. */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+
+#define MDIO_CTRL_0_REG 0x40
+#define MDIO_CTRL_1_REG 0x44
+#define MDIO_CTRL_2_REG 0x48
+#define MDIO_CTRL_3_REG 0x4c
+#define MDIO_CTRL_4_REG 0x50
+#define MDIO_CTRL_4_ACCESS_BUSY BIT(16)
+#define MDIO_CTRL_4_ACCESS_START BIT(8)
+#define MDIO_CTRL_4_ACCESS_CODE_READ 0
+#define MDIO_CTRL_4_ACCESS_CODE_WRITE 1
+
+#define IPQ40XX_MDIO_RETRY 1000
+#define IPQ40XX_MDIO_DELAY 10
+
+struct ipq40xx_mdio_data {
+ void __iomem *membase;
+};
+
+static int ipq40xx_mdio_wait_busy(struct mii_bus *bus)
+{
+ struct ipq40xx_mdio_data *priv = bus->priv;
+ int i;
+
+ for (i = 0; i < IPQ40XX_MDIO_RETRY; i++) {
+ unsigned int busy;
+
+ busy = readl(priv->membase + MDIO_CTRL_4_REG) &
+ MDIO_CTRL_4_ACCESS_BUSY;
+ if (!busy)
+ return 0;
+
+ /* BUSY might take to be cleard by 15~20 times of loop */
+ udelay(IPQ40XX_MDIO_DELAY);
+ }
+
+ dev_err(bus->parent, "MDIO operation timed out\n");
+
+ return -ETIMEDOUT;
+}
+
+static int ipq40xx_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+ struct ipq40xx_mdio_data *priv = bus->priv;
+ int value = 0;
+ unsigned int cmd = 0;
+
+ /* Reject clause 45 */
+ if (regnum & MII_ADDR_C45)
+ return -EOPNOTSUPP;
+
+ if (ipq40xx_mdio_wait_busy(bus))
+ return -ETIMEDOUT;
+
+ /* issue the phy address and reg */
+ writel((mii_id << 8) | regnum, priv->membase + MDIO_CTRL_1_REG);
+
+ cmd = MDIO_CTRL_4_ACCESS_START | MDIO_CTRL_4_ACCESS_CODE_READ;
+
+ /* issue read command */
+ writel(cmd, priv->membase + MDIO_CTRL_4_REG);
+
+ /* Wait read complete */
+ if (ipq40xx_mdio_wait_busy(bus))
+ return -ETIMEDOUT;
+
+ /* Read data */
+ value = readl(priv->membase + MDIO_CTRL_3_REG);
+
+ return value;
+}
+
+static int ipq40xx_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
+ u16 value)
+{
+ struct ipq40xx_mdio_data *priv = bus->priv;
+ unsigned int cmd = 0;
+
+ /* Reject clause 45 */
+ if (regnum & MII_ADDR_C45)
+ return -EOPNOTSUPP;
+
+ if (ipq40xx_mdio_wait_busy(bus))
+ return -ETIMEDOUT;
+
+ /* issue the phy address and reg */
+ writel((mii_id << 8) | regnum, priv->membase + MDIO_CTRL_1_REG);
+
+ /* issue write data */
+ writel(value, priv->membase + MDIO_CTRL_2_REG);
+
+ cmd = MDIO_CTRL_4_ACCESS_START | MDIO_CTRL_4_ACCESS_CODE_WRITE;
+ /* issue write command */
+ writel(cmd, priv->membase + MDIO_CTRL_4_REG);
+
+ /* Wait write complete */
+ if (ipq40xx_mdio_wait_busy(bus))
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+static int ipq40xx_mdio_probe(struct platform_device *pdev)
+{
+ struct ipq40xx_mdio_data *priv;
+ struct mii_bus *bus;
+ int ret;
+
+ bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
+ if (!bus)
+ return -ENOMEM;
+
+ priv = bus->priv;
+
+ priv->membase = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->membase))
+ return PTR_ERR(priv->membase);
+
+ bus->name = "ipq40xx_mdio";
+ bus->read = ipq40xx_mdio_read;
+ bus->write = ipq40xx_mdio_write;
+ bus->parent = &pdev->dev;
+ snprintf(bus->id, MII_BUS_ID_SIZE, "%s%d", pdev->name, pdev->id);
+
+ ret = of_mdiobus_register(bus, pdev->dev.of_node);
+ if (ret) {
+ dev_err(&pdev->dev, "Cannot register MDIO bus!\n");
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, bus);
+
+ return 0;
+}
+
+static int ipq40xx_mdio_remove(struct platform_device *pdev)
+{
+ struct mii_bus *bus = platform_get_drvdata(pdev);
+
+ mdiobus_unregister(bus);
+
+ return 0;
+}
+
+static const struct of_device_id ipq40xx_mdio_dt_ids[] = {
+ { .compatible = "qcom,ipq40xx-mdio" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ipq40xx_mdio_dt_ids);
+
+static struct platform_driver ipq40xx_mdio_driver = {
+ .probe = ipq40xx_mdio_probe,
+ .remove = ipq40xx_mdio_remove,
+ .driver = {
+ .name = "ipq40xx-mdio",
+ .of_match_table = ipq40xx_mdio_dt_ids,
+ },
+};
+
+module_platform_driver(ipq40xx_mdio_driver);
+
+MODULE_DESCRIPTION("IPQ40XX MDIO interface driver");
+MODULE_AUTHOR("Qualcomm Atheros");
+MODULE_LICENSE("Dual BSD/GPL");
--
2.26.0
