2013-04-29 19:38:55

by [email protected]

[permalink] [raw]
Subject: [PATCH 2/6] net: Add MDIO bus driver for the Allwinner EMAC

This patch adds a separate driver for the MDIO interface of the
Allwinner ethernet controllers.

Signed-off-by: Maxime Ripard <[email protected]>
---
.../bindings/net/allwinner,sun4i-mdio.txt | 26 +++
drivers/net/ethernet/allwinner/Kconfig | 8 +
drivers/net/ethernet/allwinner/Makefile | 1 +
drivers/net/ethernet/allwinner/sun4i-mdio.c | 191 +++++++++++++++++++++
4 files changed, 226 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/allwinner,sun4i-mdio.txt
create mode 100644 drivers/net/ethernet/allwinner/sun4i-mdio.c

diff --git a/Documentation/devicetree/bindings/net/allwinner,sun4i-mdio.txt b/Documentation/devicetree/bindings/net/allwinner,sun4i-mdio.txt
new file mode 100644
index 0000000..00b9f9a
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/allwinner,sun4i-mdio.txt
@@ -0,0 +1,26 @@
+* Allwinner A10 MDIO Ethernet Controller interface
+
+Required properties:
+- compatible: should be "allwinner,sun4i-mdio".
+- reg: address and length of the register set for the device.
+
+Optional properties:
+- phy-supply: phandle to a regulator if the PHY needs one
+
+Example at the SoC level:
[email protected] {
+ compatible = "allwinner,sun4i-mdio";
+ reg = <0x01c0b080 0x14>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+};
+
+And at the board level:
+
[email protected] {
+ phy-supply = <&reg_emac_3v3>;
+
+ phy0: [email protected] {
+ reg = <0>;
+ };
+};
diff --git a/drivers/net/ethernet/allwinner/Kconfig b/drivers/net/ethernet/allwinner/Kconfig
index 5d20fb0..7bbd500 100644
--- a/drivers/net/ethernet/allwinner/Kconfig
+++ b/drivers/net/ethernet/allwinner/Kconfig
@@ -27,10 +27,18 @@ config SUN4I_EMAC
select NET_CORE
select MII
select REGULATOR_FIXED_VOLTAGE
+ select PHYLIB
---help---
Support for Allwinner A10 EMAC ethernet driver.

To compile this driver as a module, choose M here. The module
will be called sun4i-emac.

+config SUN4I_MDIO
+ tristate "Allwinner sun4i MDIO interface support"
+ ---help---
+ This driver supports the MDIO interface found in the network
+ interface units of the Allwinner SoC that have an EMAC (A10,
+ A12, A10s, etc.)
+
endif # NET_VENDOR_ALLWINNER
diff --git a/drivers/net/ethernet/allwinner/Makefile b/drivers/net/ethernet/allwinner/Makefile
index 03129f7..95eaa31 100644
--- a/drivers/net/ethernet/allwinner/Makefile
+++ b/drivers/net/ethernet/allwinner/Makefile
@@ -3,3 +3,4 @@
#

obj-$(CONFIG_SUN4I_EMAC) += sun4i-emac.o
+obj-$(CONFIG_SUN4I_MDIO) += sun4i-mdio.o
\ No newline at end of file
diff --git a/drivers/net/ethernet/allwinner/sun4i-mdio.c b/drivers/net/ethernet/allwinner/sun4i-mdio.c
new file mode 100644
index 0000000..00e432c
--- /dev/null
+++ b/drivers/net/ethernet/allwinner/sun4i-mdio.c
@@ -0,0 +1,191 @@
+/*
+ * Allwinner EMAC MDIO interface driver
+ *
+ * Copyright 2012-2013 Stefan Roese <[email protected]>
+ * Copyright 2013 Maxime Ripard <[email protected]>
+ *
+ * Based on the Linux driver provided by Allwinner:
+ * Copyright (C) 1997 Sten Wang
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+
+#define EMAC_MAC_MCMD_REG (0x00)
+#define EMAC_MAC_MADR_REG (0x04)
+#define EMAC_MAC_MWTD_REG (0x08)
+#define EMAC_MAC_MRDD_REG (0x0c)
+#define EMAC_MAC_MIND_REG (0x10)
+#define EMAC_MAC_SSRR_REG (0x14)
+
+#define MDIO_TIMEOUT (msecs_to_jiffies(100))
+
+struct sun4i_mdio_data {
+ void __iomem *membase;
+ struct regulator *regulator;
+};
+
+static int sun4i_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+ struct sun4i_mdio_data *data = bus->priv;
+ unsigned long start_jiffies;
+ int value;
+
+ /* issue the phy address and reg */
+ writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
+ /* pull up the phy io line */
+ writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
+
+ /* Wait read complete */
+ start_jiffies = jiffies;
+ while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
+ if (time_after(start_jiffies,
+ start_jiffies + MDIO_TIMEOUT))
+ return -ETIMEDOUT;
+ msleep(1);
+ }
+
+ /* push down the phy io line */
+ writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
+ /* and read data */
+ value = readl(data->membase + EMAC_MAC_MRDD_REG);
+
+ return value;
+}
+
+static int sun4i_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
+ u16 value)
+{
+ struct sun4i_mdio_data *data = bus->priv;
+ unsigned long start_jiffies;
+
+ /* issue the phy address and reg */
+ writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
+ /* pull up the phy io line */
+ writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
+
+ /* Wait read complete */
+ start_jiffies = jiffies;
+ while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
+ if (time_after(start_jiffies,
+ start_jiffies + MDIO_TIMEOUT))
+ return -ETIMEDOUT;
+ msleep(1);
+ }
+
+ /* push down the phy io line */
+ writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
+ /* and write data */
+ writel(value, data->membase + EMAC_MAC_MWTD_REG);
+
+ return 0;
+}
+
+static int sun4i_mdio_reset(struct mii_bus *bus)
+{
+ return 0;
+}
+
+static int sun4i_mdio_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct mii_bus *bus;
+ struct sun4i_mdio_data *data;
+ int ret, i;
+
+ bus = mdiobus_alloc_size(sizeof(*data));
+ if (!bus)
+ return -ENOMEM;
+
+ bus->name = "sun4i_mii_bus";
+ bus->read = &sun4i_mdio_read;
+ bus->write = &sun4i_mdio_write;
+ bus->reset = &sun4i_mdio_reset;
+ snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
+ bus->parent = &pdev->dev;
+
+ bus->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
+ if (!bus->irq) {
+ ret = -ENOMEM;
+ goto err_out_free_mdiobus;
+ }
+
+ for (i = 0; i < PHY_MAX_ADDR; i++)
+ bus->irq[i] = PHY_POLL;
+
+ data = bus->priv;
+ data->membase = of_iomap(np, 0);
+ if (!data->membase) {
+ ret = -ENOMEM;
+ goto err_out_free_mdio_irq;
+ }
+
+ data->regulator = devm_regulator_get(&pdev->dev, "phy");
+ if (IS_ERR(data->regulator)) {
+ if (PTR_ERR(data->regulator) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
+ dev_info(&pdev->dev, "no regulator found\n");
+ } else
+ regulator_enable(data->regulator);
+
+ ret = of_mdiobus_register(bus, np);
+ if (ret < 0)
+ goto err_out_disable_regulator;
+
+ platform_set_drvdata(pdev, bus);
+
+ return 0;
+
+err_out_disable_regulator:
+ regulator_disable(data->regulator);
+err_out_free_mdio_irq:
+ kfree(bus->irq);
+err_out_free_mdiobus:
+ mdiobus_free(bus);
+ return ret;
+}
+
+static int sun4i_mdio_remove(struct platform_device *pdev)
+{
+ struct mii_bus *bus = platform_get_drvdata(pdev);
+
+ mdiobus_unregister(bus);
+ kfree(bus->irq);
+ mdiobus_free(bus);
+
+ return 0;
+}
+
+static const struct of_device_id sun4i_mdio_dt_ids[] = {
+ { .compatible = "allwinner,sun4i-mdio" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, sun4i_mdio_dt_ids);
+
+static struct platform_driver sun4i_mdio_driver = {
+ .probe = sun4i_mdio_probe,
+ .remove = sun4i_mdio_remove,
+ .driver = {
+ .name = "sun4i-mdio",
+ .of_match_table = sun4i_mdio_dt_ids,
+ },
+};
+
+module_platform_driver(sun4i_mdio_driver);
+
+MODULE_DESCRIPTION("Allwinner EMAC MDIO interface driver");
+MODULE_AUTHOR("Maxime Ripard <[email protected]>");
+MODULE_LICENSE("GPL");
--
1.8.1.2