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/module.h>
22 #include <linux/phy.h>
23 #include <linux/platform_device.h>
24 #include <linux/of_net.h>
25 #include <linux/regulator/consumer.h>
26
27 #include "stmmac_platform.h"
28
29 struct sunxi_priv_data {
30 int interface;
31 int clk_enabled;
32 struct clk *tx_clk;
33 struct regulator *regulator;
34 };
35
36 #define SUN7I_GMAC_GMII_RGMII_RATE 125000000
37 #define SUN7I_GMAC_MII_RATE 25000000
38
sun7i_gmac_init(struct platform_device * pdev,void * priv)39 static int sun7i_gmac_init(struct platform_device *pdev, void *priv)
40 {
41 struct sunxi_priv_data *gmac = priv;
42 int ret;
43
44 if (gmac->regulator) {
45 ret = regulator_enable(gmac->regulator);
46 if (ret)
47 return ret;
48 }
49
50 /* Set GMAC interface port mode
51 *
52 * The GMAC TX clock lines are configured by setting the clock
53 * rate, which then uses the auto-reparenting feature of the
54 * clock driver, and enabling/disabling the clock.
55 */
56 if (gmac->interface == PHY_INTERFACE_MODE_RGMII) {
57 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
58 clk_prepare_enable(gmac->tx_clk);
59 gmac->clk_enabled = 1;
60 } else {
61 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
62 clk_prepare(gmac->tx_clk);
63 }
64
65 return 0;
66 }
67
sun7i_gmac_exit(struct platform_device * pdev,void * priv)68 static void sun7i_gmac_exit(struct platform_device *pdev, void *priv)
69 {
70 struct sunxi_priv_data *gmac = priv;
71
72 if (gmac->clk_enabled) {
73 clk_disable(gmac->tx_clk);
74 gmac->clk_enabled = 0;
75 }
76 clk_unprepare(gmac->tx_clk);
77
78 if (gmac->regulator)
79 regulator_disable(gmac->regulator);
80 }
81
sun7i_fix_speed(void * priv,unsigned int speed)82 static void sun7i_fix_speed(void *priv, unsigned int speed)
83 {
84 struct sunxi_priv_data *gmac = priv;
85
86 /* only GMII mode requires us to reconfigure the clock lines */
87 if (gmac->interface != PHY_INTERFACE_MODE_GMII)
88 return;
89
90 if (gmac->clk_enabled) {
91 clk_disable(gmac->tx_clk);
92 gmac->clk_enabled = 0;
93 }
94 clk_unprepare(gmac->tx_clk);
95
96 if (speed == 1000) {
97 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE);
98 clk_prepare_enable(gmac->tx_clk);
99 gmac->clk_enabled = 1;
100 } else {
101 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE);
102 clk_prepare(gmac->tx_clk);
103 }
104 }
105
sun7i_gmac_probe(struct platform_device * pdev)106 static int sun7i_gmac_probe(struct platform_device *pdev)
107 {
108 struct plat_stmmacenet_data *plat_dat;
109 struct stmmac_resources stmmac_res;
110 struct sunxi_priv_data *gmac;
111 struct device *dev = &pdev->dev;
112 int ret;
113
114 ret = stmmac_get_platform_resources(pdev, &stmmac_res);
115 if (ret)
116 return ret;
117
118 plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
119 if (IS_ERR(plat_dat))
120 return PTR_ERR(plat_dat);
121
122 gmac = devm_kzalloc(dev, sizeof(*gmac), GFP_KERNEL);
123 if (!gmac) {
124 ret = -ENOMEM;
125 goto err_remove_config_dt;
126 }
127
128 gmac->interface = of_get_phy_mode(dev->of_node);
129
130 gmac->tx_clk = devm_clk_get(dev, "allwinner_gmac_tx");
131 if (IS_ERR(gmac->tx_clk)) {
132 dev_err(dev, "could not get tx clock\n");
133 ret = PTR_ERR(gmac->tx_clk);
134 goto err_remove_config_dt;
135 }
136
137 /* Optional regulator for PHY */
138 gmac->regulator = devm_regulator_get_optional(dev, "phy");
139 if (IS_ERR(gmac->regulator)) {
140 if (PTR_ERR(gmac->regulator) == -EPROBE_DEFER) {
141 ret = -EPROBE_DEFER;
142 goto err_remove_config_dt;
143 }
144 dev_info(dev, "no regulator found\n");
145 gmac->regulator = NULL;
146 }
147
148 /* platform data specifying hardware features and callbacks.
149 * hardware features were copied from Allwinner drivers. */
150 plat_dat->tx_coe = 1;
151 plat_dat->has_gmac = true;
152 plat_dat->bsp_priv = gmac;
153 plat_dat->init = sun7i_gmac_init;
154 plat_dat->exit = sun7i_gmac_exit;
155 plat_dat->fix_mac_speed = sun7i_fix_speed;
156
157 ret = sun7i_gmac_init(pdev, plat_dat->bsp_priv);
158 if (ret)
159 goto err_remove_config_dt;
160
161 ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
162 if (ret)
163 goto err_gmac_exit;
164
165 return 0;
166
167 err_gmac_exit:
168 sun7i_gmac_exit(pdev, plat_dat->bsp_priv);
169 err_remove_config_dt:
170 stmmac_remove_config_dt(pdev, plat_dat);
171
172 return ret;
173 }
174
175 static const struct of_device_id sun7i_dwmac_match[] = {
176 { .compatible = "allwinner,sun7i-a20-gmac" },
177 { }
178 };
179 MODULE_DEVICE_TABLE(of, sun7i_dwmac_match);
180
181 static struct platform_driver sun7i_dwmac_driver = {
182 .probe = sun7i_gmac_probe,
183 .remove = stmmac_pltfr_remove,
184 .driver = {
185 .name = "sun7i-dwmac",
186 .pm = &stmmac_pltfr_pm_ops,
187 .of_match_table = sun7i_dwmac_match,
188 },
189 };
190 module_platform_driver(sun7i_dwmac_driver);
191
192 MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
193 MODULE_DESCRIPTION("Allwinner sunxi DWMAC specific glue layer");
194 MODULE_LICENSE("GPL");
195
