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 static void *sun7i_gmac_setup(struct platform_device *pdev) 37 { 38 struct sunxi_priv_data *gmac; 39 struct device *dev = &pdev->dev; 40 41 gmac = devm_kzalloc(dev, sizeof(*gmac), GFP_KERNEL); 42 if (!gmac) 43 return ERR_PTR(-ENOMEM); 44 45 gmac->interface = of_get_phy_mode(dev->of_node); 46 47 gmac->tx_clk = devm_clk_get(dev, "allwinner_gmac_tx"); 48 if (IS_ERR(gmac->tx_clk)) { 49 dev_err(dev, "could not get tx clock\n"); 50 return gmac->tx_clk; 51 } 52 53 /* Optional regulator for PHY */ 54 gmac->regulator = devm_regulator_get_optional(dev, "phy"); 55 if (IS_ERR(gmac->regulator)) { 56 if (PTR_ERR(gmac->regulator) == -EPROBE_DEFER) 57 return ERR_PTR(-EPROBE_DEFER); 58 dev_info(dev, "no regulator found\n"); 59 gmac->regulator = NULL; 60 } 61 62 return gmac; 63 } 64 65 #define SUN7I_GMAC_GMII_RGMII_RATE 125000000 66 #define SUN7I_GMAC_MII_RATE 25000000 67 68 static int sun7i_gmac_init(struct platform_device *pdev, void *priv) 69 { 70 struct sunxi_priv_data *gmac = priv; 71 int ret; 72 73 if (gmac->regulator) { 74 ret = regulator_enable(gmac->regulator); 75 if (ret) 76 return ret; 77 } 78 79 /* Set GMAC interface port mode 80 * 81 * The GMAC TX clock lines are configured by setting the clock 82 * rate, which then uses the auto-reparenting feature of the 83 * clock driver, and enabling/disabling the clock. 84 */ 85 if (gmac->interface == PHY_INTERFACE_MODE_RGMII) { 86 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE); 87 clk_prepare_enable(gmac->tx_clk); 88 gmac->clk_enabled = 1; 89 } else { 90 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE); 91 clk_prepare(gmac->tx_clk); 92 } 93 94 return 0; 95 } 96 97 static void sun7i_gmac_exit(struct platform_device *pdev, void *priv) 98 { 99 struct sunxi_priv_data *gmac = priv; 100 101 if (gmac->clk_enabled) { 102 clk_disable(gmac->tx_clk); 103 gmac->clk_enabled = 0; 104 } 105 clk_unprepare(gmac->tx_clk); 106 107 if (gmac->regulator) 108 regulator_disable(gmac->regulator); 109 } 110 111 static void sun7i_fix_speed(void *priv, unsigned int speed) 112 { 113 struct sunxi_priv_data *gmac = priv; 114 115 /* only GMII mode requires us to reconfigure the clock lines */ 116 if (gmac->interface != PHY_INTERFACE_MODE_GMII) 117 return; 118 119 if (gmac->clk_enabled) { 120 clk_disable(gmac->tx_clk); 121 gmac->clk_enabled = 0; 122 } 123 clk_unprepare(gmac->tx_clk); 124 125 if (speed == 1000) { 126 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_GMII_RGMII_RATE); 127 clk_prepare_enable(gmac->tx_clk); 128 gmac->clk_enabled = 1; 129 } else { 130 clk_set_rate(gmac->tx_clk, SUN7I_GMAC_MII_RATE); 131 clk_prepare(gmac->tx_clk); 132 } 133 } 134 135 /* of_data specifying hardware features and callbacks. 136 * hardware features were copied from Allwinner drivers. */ 137 static const struct stmmac_of_data sun7i_gmac_data = { 138 .has_gmac = 1, 139 .tx_coe = 1, 140 .fix_mac_speed = sun7i_fix_speed, 141 .setup = sun7i_gmac_setup, 142 .init = sun7i_gmac_init, 143 .exit = sun7i_gmac_exit, 144 }; 145 146 static const struct of_device_id sun7i_dwmac_match[] = { 147 { .compatible = "allwinner,sun7i-a20-gmac", .data = &sun7i_gmac_data}, 148 { } 149 }; 150 MODULE_DEVICE_TABLE(of, sun7i_dwmac_match); 151 152 static struct platform_driver sun7i_dwmac_driver = { 153 .probe = stmmac_pltfr_probe, 154 .remove = stmmac_pltfr_remove, 155 .driver = { 156 .name = "sun7i-dwmac", 157 .pm = &stmmac_pltfr_pm_ops, 158 .of_match_table = sun7i_dwmac_match, 159 }, 160 }; 161 module_platform_driver(sun7i_dwmac_driver); 162 163 MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>"); 164 MODULE_DESCRIPTION("Allwinner sunxi DWMAC specific glue layer"); 165 MODULE_LICENSE("GPL"); 166