Linux 4.1.16
[linux/fpc-iii.git] / drivers / net / phy / mdio-bcm-unimac.c
blob414fdf1f343fe61549fef390ac3e417d1bc928e4
1 /*
2 * Broadcom UniMAC MDIO bus controller driver
4 * Copyright (C) 2014, Broadcom Corporation
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
12 #include <linux/kernel.h>
13 #include <linux/phy.h>
14 #include <linux/platform_device.h>
15 #include <linux/sched.h>
16 #include <linux/module.h>
17 #include <linux/io.h>
18 #include <linux/delay.h>
20 #include <linux/of.h>
21 #include <linux/of_platform.h>
22 #include <linux/of_mdio.h>
24 #define MDIO_CMD 0x00
25 #define MDIO_START_BUSY (1 << 29)
26 #define MDIO_READ_FAIL (1 << 28)
27 #define MDIO_RD (2 << 26)
28 #define MDIO_WR (1 << 26)
29 #define MDIO_PMD_SHIFT 21
30 #define MDIO_PMD_MASK 0x1F
31 #define MDIO_REG_SHIFT 16
32 #define MDIO_REG_MASK 0x1F
34 #define MDIO_CFG 0x04
35 #define MDIO_C22 (1 << 0)
36 #define MDIO_C45 0
37 #define MDIO_CLK_DIV_SHIFT 4
38 #define MDIO_CLK_DIV_MASK 0x3F
39 #define MDIO_SUPP_PREAMBLE (1 << 12)
41 struct unimac_mdio_priv {
42 struct mii_bus *mii_bus;
43 void __iomem *base;
46 static inline void unimac_mdio_start(struct unimac_mdio_priv *priv)
48 u32 reg;
50 reg = __raw_readl(priv->base + MDIO_CMD);
51 reg |= MDIO_START_BUSY;
52 __raw_writel(reg, priv->base + MDIO_CMD);
55 static inline unsigned int unimac_mdio_busy(struct unimac_mdio_priv *priv)
57 return __raw_readl(priv->base + MDIO_CMD) & MDIO_START_BUSY;
60 static int unimac_mdio_read(struct mii_bus *bus, int phy_id, int reg)
62 struct unimac_mdio_priv *priv = bus->priv;
63 unsigned int timeout = 1000;
64 u32 cmd;
66 /* Prepare the read operation */
67 cmd = MDIO_RD | (phy_id << MDIO_PMD_SHIFT) | (reg << MDIO_REG_SHIFT);
68 __raw_writel(cmd, priv->base + MDIO_CMD);
70 /* Start MDIO transaction */
71 unimac_mdio_start(priv);
73 do {
74 if (!unimac_mdio_busy(priv))
75 break;
77 usleep_range(1000, 2000);
78 } while (timeout--);
80 if (!timeout)
81 return -ETIMEDOUT;
83 cmd = __raw_readl(priv->base + MDIO_CMD);
84 if (cmd & MDIO_READ_FAIL)
85 return -EIO;
87 return cmd & 0xffff;
90 static int unimac_mdio_write(struct mii_bus *bus, int phy_id,
91 int reg, u16 val)
93 struct unimac_mdio_priv *priv = bus->priv;
94 unsigned int timeout = 1000;
95 u32 cmd;
97 /* Prepare the write operation */
98 cmd = MDIO_WR | (phy_id << MDIO_PMD_SHIFT) |
99 (reg << MDIO_REG_SHIFT) | (0xffff & val);
100 __raw_writel(cmd, priv->base + MDIO_CMD);
102 unimac_mdio_start(priv);
104 do {
105 if (!unimac_mdio_busy(priv))
106 break;
108 usleep_range(1000, 2000);
109 } while (timeout--);
111 if (!timeout)
112 return -ETIMEDOUT;
114 return 0;
117 static int unimac_mdio_probe(struct platform_device *pdev)
119 struct unimac_mdio_priv *priv;
120 struct device_node *np;
121 struct mii_bus *bus;
122 struct resource *r;
123 int ret;
125 np = pdev->dev.of_node;
127 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
128 if (!priv)
129 return -ENOMEM;
131 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
133 /* Just ioremap, as this MDIO block is usually integrated into an
134 * Ethernet MAC controller register range
136 priv->base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
137 if (!priv->base) {
138 dev_err(&pdev->dev, "failed to remap register\n");
139 return -ENOMEM;
142 priv->mii_bus = mdiobus_alloc();
143 if (!priv->mii_bus)
144 return -ENOMEM;
146 bus = priv->mii_bus;
147 bus->priv = priv;
148 bus->name = "unimac MII bus";
149 bus->parent = &pdev->dev;
150 bus->read = unimac_mdio_read;
151 bus->write = unimac_mdio_write;
152 snprintf(bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);
154 bus->irq = kcalloc(PHY_MAX_ADDR, sizeof(int), GFP_KERNEL);
155 if (!bus->irq) {
156 ret = -ENOMEM;
157 goto out_mdio_free;
160 ret = of_mdiobus_register(bus, np);
161 if (ret) {
162 dev_err(&pdev->dev, "MDIO bus registration failed\n");
163 goto out_mdio_irq;
166 platform_set_drvdata(pdev, priv);
168 dev_info(&pdev->dev, "Broadcom UniMAC MDIO bus at 0x%p\n", priv->base);
170 return 0;
172 out_mdio_irq:
173 kfree(bus->irq);
174 out_mdio_free:
175 mdiobus_free(bus);
176 return ret;
179 static int unimac_mdio_remove(struct platform_device *pdev)
181 struct unimac_mdio_priv *priv = platform_get_drvdata(pdev);
183 mdiobus_unregister(priv->mii_bus);
184 kfree(priv->mii_bus->irq);
185 mdiobus_free(priv->mii_bus);
187 return 0;
190 static const struct of_device_id unimac_mdio_ids[] = {
191 { .compatible = "brcm,genet-mdio-v4", },
192 { .compatible = "brcm,genet-mdio-v3", },
193 { .compatible = "brcm,genet-mdio-v2", },
194 { .compatible = "brcm,genet-mdio-v1", },
195 { .compatible = "brcm,unimac-mdio", },
196 { /* sentinel */ },
199 static struct platform_driver unimac_mdio_driver = {
200 .driver = {
201 .name = "unimac-mdio",
202 .of_match_table = unimac_mdio_ids,
204 .probe = unimac_mdio_probe,
205 .remove = unimac_mdio_remove,
207 module_platform_driver(unimac_mdio_driver);
209 MODULE_AUTHOR("Broadcom Corporation");
210 MODULE_DESCRIPTION("Broadcom UniMAC MDIO bus controller");
211 MODULE_LICENSE("GPL");
212 MODULE_ALIAS("platform:unimac-mdio");