2 * Copyright (C) 2015 Broadcom Corporation
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation version 2.
8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9 * kind, whether express or implied; without even the implied warranty
10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
14 #include <linux/delay.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
19 #include <linux/of_platform.h>
20 #include <linux/of_mdio.h>
21 #include <linux/phy.h>
22 #include <linux/platform_device.h>
23 #include <linux/sched.h>
25 #define IPROC_GPHY_MDCDIV 0x1a
27 #define MII_CTRL_OFFSET 0x000
29 #define MII_CTRL_DIV_SHIFT 0
30 #define MII_CTRL_PRE_SHIFT 7
31 #define MII_CTRL_BUSY_SHIFT 8
33 #define MII_DATA_OFFSET 0x004
34 #define MII_DATA_MASK 0xffff
35 #define MII_DATA_TA_SHIFT 16
36 #define MII_DATA_TA_VAL 2
37 #define MII_DATA_RA_SHIFT 18
38 #define MII_DATA_PA_SHIFT 23
39 #define MII_DATA_OP_SHIFT 28
40 #define MII_DATA_OP_WRITE 1
41 #define MII_DATA_OP_READ 2
42 #define MII_DATA_SB_SHIFT 30
44 struct iproc_mdio_priv {
45 struct mii_bus *mii_bus;
49 static inline int iproc_mdio_wait_for_idle(void __iomem *base)
52 unsigned int timeout = 1000; /* loop for 1s */
55 val = readl(base + MII_CTRL_OFFSET);
56 if ((val & BIT(MII_CTRL_BUSY_SHIFT)) == 0)
59 usleep_range(1000, 2000);
65 static inline void iproc_mdio_config_clk(void __iomem *base)
69 val = (IPROC_GPHY_MDCDIV << MII_CTRL_DIV_SHIFT) |
70 BIT(MII_CTRL_PRE_SHIFT);
71 writel(val, base + MII_CTRL_OFFSET);
74 static int iproc_mdio_read(struct mii_bus *bus, int phy_id, int reg)
76 struct iproc_mdio_priv *priv = bus->priv;
80 rc = iproc_mdio_wait_for_idle(priv->base);
84 /* Prepare the read operation */
85 cmd = (MII_DATA_TA_VAL << MII_DATA_TA_SHIFT) |
86 (reg << MII_DATA_RA_SHIFT) |
87 (phy_id << MII_DATA_PA_SHIFT) |
88 BIT(MII_DATA_SB_SHIFT) |
89 (MII_DATA_OP_READ << MII_DATA_OP_SHIFT);
91 writel(cmd, priv->base + MII_DATA_OFFSET);
93 rc = iproc_mdio_wait_for_idle(priv->base);
97 cmd = readl(priv->base + MII_DATA_OFFSET) & MII_DATA_MASK;
102 static int iproc_mdio_write(struct mii_bus *bus, int phy_id,
105 struct iproc_mdio_priv *priv = bus->priv;
109 rc = iproc_mdio_wait_for_idle(priv->base);
113 /* Prepare the write operation */
114 cmd = (MII_DATA_TA_VAL << MII_DATA_TA_SHIFT) |
115 (reg << MII_DATA_RA_SHIFT) |
116 (phy_id << MII_DATA_PA_SHIFT) |
117 BIT(MII_DATA_SB_SHIFT) |
118 (MII_DATA_OP_WRITE << MII_DATA_OP_SHIFT) |
119 ((u32)(val) & MII_DATA_MASK);
121 writel(cmd, priv->base + MII_DATA_OFFSET);
123 rc = iproc_mdio_wait_for_idle(priv->base);
130 static int iproc_mdio_probe(struct platform_device *pdev)
132 struct iproc_mdio_priv *priv;
134 struct resource *res;
137 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
141 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
142 priv->base = devm_ioremap_resource(&pdev->dev, res);
143 if (IS_ERR(priv->base)) {
144 dev_err(&pdev->dev, "failed to ioremap register\n");
145 return PTR_ERR(priv->base);
148 priv->mii_bus = mdiobus_alloc();
149 if (!priv->mii_bus) {
150 dev_err(&pdev->dev, "MDIO bus alloc failed\n");
156 bus->name = "iProc MDIO bus";
157 snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id);
158 bus->parent = &pdev->dev;
159 bus->read = iproc_mdio_read;
160 bus->write = iproc_mdio_write;
162 iproc_mdio_config_clk(priv->base);
164 rc = of_mdiobus_register(bus, pdev->dev.of_node);
166 dev_err(&pdev->dev, "MDIO bus registration failed\n");
170 platform_set_drvdata(pdev, priv);
172 dev_info(&pdev->dev, "Broadcom iProc MDIO bus at 0x%p\n", priv->base);
181 static int iproc_mdio_remove(struct platform_device *pdev)
183 struct iproc_mdio_priv *priv = platform_get_drvdata(pdev);
185 mdiobus_unregister(priv->mii_bus);
186 mdiobus_free(priv->mii_bus);
191 #ifdef CONFIG_PM_SLEEP
192 int iproc_mdio_resume(struct device *dev)
194 struct platform_device *pdev = to_platform_device(dev);
195 struct iproc_mdio_priv *priv = platform_get_drvdata(pdev);
197 /* restore the mii clock configuration */
198 iproc_mdio_config_clk(priv->base);
203 static const struct dev_pm_ops iproc_mdio_pm_ops = {
204 .resume = iproc_mdio_resume
206 #endif /* CONFIG_PM_SLEEP */
208 static const struct of_device_id iproc_mdio_of_match[] = {
209 { .compatible = "brcm,iproc-mdio", },
212 MODULE_DEVICE_TABLE(of, iproc_mdio_of_match);
214 static struct platform_driver iproc_mdio_driver = {
216 .name = "iproc-mdio",
217 .of_match_table = iproc_mdio_of_match,
218 #ifdef CONFIG_PM_SLEEP
219 .pm = &iproc_mdio_pm_ops,
222 .probe = iproc_mdio_probe,
223 .remove = iproc_mdio_remove,
226 module_platform_driver(iproc_mdio_driver);
228 MODULE_AUTHOR("Broadcom Corporation");
229 MODULE_DESCRIPTION("Broadcom iProc MDIO bus controller");
230 MODULE_LICENSE("GPL v2");
231 MODULE_ALIAS("platform:iproc-mdio");