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path: root/drivers/net/mdio/mdio-ipq8064.c
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Diffstat (limited to 'drivers/net/mdio/mdio-ipq8064.c')
-rw-r--r--drivers/net/mdio/mdio-ipq8064.c188
1 files changed, 188 insertions, 0 deletions
diff --git a/drivers/net/mdio/mdio-ipq8064.c b/drivers/net/mdio/mdio-ipq8064.c
new file mode 100644
index 000000000..37e0d8b6d
--- /dev/null
+++ b/drivers/net/mdio/mdio-ipq8064.c
@@ -0,0 +1,188 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Qualcomm IPQ8064 MDIO interface driver
+ *
+ * Copyright (C) 2019 Christian Lamparter <chunkeey@gmail.com>
+ * Copyright (C) 2020 Ansuel Smith <ansuelsmth@gmail.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_mdio.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* MII address register definitions */
+#define MII_ADDR_REG_ADDR 0x10
+#define MII_BUSY BIT(0)
+#define MII_WRITE BIT(1)
+#define MII_CLKRANGE(x) ((x) << 2)
+#define MII_CLKRANGE_60_100M MII_CLKRANGE(0)
+#define MII_CLKRANGE_100_150M MII_CLKRANGE(1)
+#define MII_CLKRANGE_20_35M MII_CLKRANGE(2)
+#define MII_CLKRANGE_35_60M MII_CLKRANGE(3)
+#define MII_CLKRANGE_150_250M MII_CLKRANGE(4)
+#define MII_CLKRANGE_250_300M MII_CLKRANGE(5)
+#define MII_CLKRANGE_MASK GENMASK(4, 2)
+#define MII_REG_SHIFT 6
+#define MII_REG_MASK GENMASK(10, 6)
+#define MII_ADDR_SHIFT 11
+#define MII_ADDR_MASK GENMASK(15, 11)
+
+#define MII_DATA_REG_ADDR 0x14
+
+#define MII_MDIO_DELAY_USEC (1000)
+#define MII_MDIO_RETRY_MSEC (10)
+
+struct ipq8064_mdio {
+ struct regmap *base; /* NSS_GMAC0_BASE */
+};
+
+static int
+ipq8064_mdio_wait_busy(struct ipq8064_mdio *priv)
+{
+ u32 busy;
+
+ return regmap_read_poll_timeout(priv->base, MII_ADDR_REG_ADDR, busy,
+ !(busy & MII_BUSY), MII_MDIO_DELAY_USEC,
+ MII_MDIO_RETRY_MSEC * USEC_PER_MSEC);
+}
+
+static int
+ipq8064_mdio_read(struct mii_bus *bus, int phy_addr, int reg_offset)
+{
+ u32 miiaddr = MII_BUSY | MII_CLKRANGE_250_300M;
+ struct ipq8064_mdio *priv = bus->priv;
+ u32 ret_val;
+ int err;
+
+ /* Reject clause 45 */
+ if (reg_offset & MII_ADDR_C45)
+ return -EOPNOTSUPP;
+
+ miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
+ ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);
+
+ regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);
+ usleep_range(10, 13);
+
+ err = ipq8064_mdio_wait_busy(priv);
+ if (err)
+ return err;
+
+ regmap_read(priv->base, MII_DATA_REG_ADDR, &ret_val);
+ return (int)ret_val;
+}
+
+static int
+ipq8064_mdio_write(struct mii_bus *bus, int phy_addr, int reg_offset, u16 data)
+{
+ u32 miiaddr = MII_WRITE | MII_BUSY | MII_CLKRANGE_250_300M;
+ struct ipq8064_mdio *priv = bus->priv;
+
+ /* Reject clause 45 */
+ if (reg_offset & MII_ADDR_C45)
+ return -EOPNOTSUPP;
+
+ regmap_write(priv->base, MII_DATA_REG_ADDR, data);
+
+ miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
+ ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);
+
+ regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);
+
+ /* For the specific reg 31 extra time is needed or the next
+ * read will produce garbage data.
+ */
+ if (reg_offset == 31)
+ usleep_range(30, 43);
+ else
+ usleep_range(10, 13);
+
+ return ipq8064_mdio_wait_busy(priv);
+}
+
+static const struct regmap_config ipq8064_mdio_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .can_multi_write = false,
+ /* the mdio lock is used by any user of this mdio driver */
+ .disable_locking = true,
+
+ .cache_type = REGCACHE_NONE,
+};
+
+static int
+ipq8064_mdio_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct ipq8064_mdio *priv;
+ struct resource res;
+ struct mii_bus *bus;
+ void __iomem *base;
+ int ret;
+
+ if (of_address_to_resource(np, 0, &res))
+ return -ENOMEM;
+
+ base = devm_ioremap(&pdev->dev, res.start, resource_size(&res));
+ if (!base)
+ return -ENOMEM;
+
+ bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
+ if (!bus)
+ return -ENOMEM;
+
+ bus->name = "ipq8064_mdio_bus";
+ bus->read = ipq8064_mdio_read;
+ bus->write = ipq8064_mdio_write;
+ snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
+ bus->parent = &pdev->dev;
+
+ priv = bus->priv;
+ priv->base = devm_regmap_init_mmio(&pdev->dev, base,
+ &ipq8064_mdio_regmap_config);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ ret = of_mdiobus_register(bus, np);
+ if (ret)
+ return ret;
+
+ platform_set_drvdata(pdev, bus);
+ return 0;
+}
+
+static int
+ipq8064_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 ipq8064_mdio_dt_ids[] = {
+ { .compatible = "qcom,ipq8064-mdio" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ipq8064_mdio_dt_ids);
+
+static struct platform_driver ipq8064_mdio_driver = {
+ .probe = ipq8064_mdio_probe,
+ .remove = ipq8064_mdio_remove,
+ .driver = {
+ .name = "ipq8064-mdio",
+ .of_match_table = ipq8064_mdio_dt_ids,
+ },
+};
+
+module_platform_driver(ipq8064_mdio_driver);
+
+MODULE_DESCRIPTION("Qualcomm IPQ8064 MDIO interface driver");
+MODULE_AUTHOR("Christian Lamparter <chunkeey@gmail.com>");
+MODULE_AUTHOR("Ansuel Smith <ansuelsmth@gmail.com>");
+MODULE_LICENSE("GPL");