1/*
2 * dwmac-sunxi.c - Allwinner sunxi DWMAC specific glue layer
3 *
4 * Copyright (C) 2013 Chen-Yu Tsai
5 *
6 * Chen-Yu Tsai  <wens@csie.org>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 */
18
19#include <linux/stmmac.h>
20#include <linux/clk.h>
21#include <linux/phy.h>
22#include <linux/of_net.h>
23#include <linux/regulator/consumer.h>
24
25#include "stmmac_platform.h"
26
27struct sunxi_priv_data {
28	int interface;
29	int clk_enabled;
30	struct clk *tx_clk;
31	struct regulator *regulator;
32};
33
34static void *sun7i_gmac_setup(struct platform_device *pdev)
35{
36	struct sunxi_priv_data *gmac;
37	struct device *dev = &pdev->dev;
38
39	gmac = devm_kzalloc(dev, sizeof(*gmac), GFP_KERNEL);
40	if (!gmac)
41		return ERR_PTR(-ENOMEM);
42
43	gmac->interface = of_get_phy_mode(dev->of_node);
44
45	gmac->tx_clk = devm_clk_get(dev, "allwinner_gmac_tx");
46	if (IS_ERR(gmac->tx_clk)) {
47		dev_err(dev, "could not get tx clock\n");
48		return gmac->tx_clk;
49	}
50
51	/* Optional regulator for PHY */
52	gmac->regulator = devm_regulator_get_optional(dev, "phy");
53	if (IS_ERR(gmac->regulator)) {
54		if (PTR_ERR(gmac->regulator) == -EPROBE_DEFER)
55			return ERR_PTR(-EPROBE_DEFER);
56		dev_info(dev, "no regulator found\n");
57		gmac->regulator = NULL;
58	}
59
60	return gmac;
61}
62
63#define SUN7I_GMAC_GMII_RGMII_RATE	125000000
64#define SUN7I_GMAC_MII_RATE		25000000
65
66static int sun7i_gmac_init(struct platform_device *pdev, void *priv)
67{
68	struct sunxi_priv_data *gmac = priv;
69	int ret;
70
71	if (gmac->regulator) {
72		ret = regulator_enable(gmac->regulator);
73		if (ret)
74			return ret;
75	}
76
77	/* Set GMAC interface port mode
78	 *
79	 * The GMAC TX clock lines are configured by setting the clock
80	 * rate, which then uses the auto-reparenting feature of the
81	 * clock driver, and enabling/disabling the clock.
82	 */
83	if (gmac->interface == PHY_INTERFACE_MODE_RGMII) {
84		clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
85		clk_prepare_enable(gmac->tx_clk);
86		gmac->clk_enabled = 1;
87	} else {
88		clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
89		clk_prepare(gmac->tx_clk);
90	}
91
92	return 0;
93}
94
95static void sun7i_gmac_exit(struct platform_device *pdev, void *priv)
96{
97	struct sunxi_priv_data *gmac = priv;
98
99	if (gmac->clk_enabled) {
100		clk_disable(gmac->tx_clk);
101		gmac->clk_enabled = 0;
102	}
103	clk_unprepare(gmac->tx_clk);
104
105	if (gmac->regulator)
106		regulator_disable(gmac->regulator);
107}
108
109static void sun7i_fix_speed(void *priv, unsigned int speed)
110{
111	struct sunxi_priv_data *gmac = priv;
112
113	/* only GMII mode requires us to reconfigure the clock lines */
114	if (gmac->interface != PHY_INTERFACE_MODE_GMII)
115		return;
116
117	if (gmac->clk_enabled) {
118		clk_disable(gmac->tx_clk);
119		gmac->clk_enabled = 0;
120	}
121	clk_unprepare(gmac->tx_clk);
122
123	if (speed == 1000) {
124		clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
125		clk_prepare_enable(gmac->tx_clk);
126		gmac->clk_enabled = 1;
127	} else {
128		clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
129		clk_prepare(gmac->tx_clk);
130	}
131}
132
133/* of_data specifying hardware features and callbacks.
134 * hardware features were copied from Allwinner drivers. */
135const struct stmmac_of_data sun7i_gmac_data = {
136	.has_gmac = 1,
137	.tx_coe = 1,
138	.fix_mac_speed = sun7i_fix_speed,
139	.setup = sun7i_gmac_setup,
140	.init = sun7i_gmac_init,
141	.exit = sun7i_gmac_exit,
142};
143