drivers/net/ethernet/stmicro/stmmac/dwmac-sunxi.c

   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
  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
  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
  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
 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");