drivers/usb/phy/phy-am335x.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/module.h>
   3 #include <linux/platform_device.h>
   4 #include <linux/dma-mapping.h>
   5 #include <linux/usb/otg.h>
   6 #include <linux/usb/usb_phy_generic.h>
   7 #include <linux/slab.h>
   8 #include <linux/clk.h>
   9 #include <linux/of.h>
  10 #include <linux/of_address.h>
  11 #include <linux/usb/of.h>
  12
  13 #include "phy-am335x-control.h"
  14 #include "phy-generic.h"
  15
  16 struct am335x_phy {
  17         struct usb_phy_generic usb_phy_gen;
  18         struct phy_control *phy_ctrl;
  19         int id;
  20         enum usb_dr_mode dr_mode;
  21 };
  22
  23 static int am335x_init(struct usb_phy *phy)
  24 {
  25         struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
  26
  27         phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
  28         return 0;
  29 }
  30
  31 static void am335x_shutdown(struct usb_phy *phy)
  32 {
  33         struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
  34
  35         phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
  36 }
  37
  38 static int am335x_phy_probe(struct platform_device *pdev)
  39 {
  40         struct am335x_phy *am_phy;
  41         struct device *dev = &pdev->dev;
  42         int ret;
  43
  44         am_phy = devm_kzalloc(dev, sizeof(*am_phy), GFP_KERNEL);
  45         if (!am_phy)
  46                 return -ENOMEM;
  47
  48         am_phy->phy_ctrl = am335x_get_phy_control(dev);
  49         if (!am_phy->phy_ctrl)
  50                 return -EPROBE_DEFER;
  51
  52         am_phy->id = of_alias_get_id(pdev->dev.of_node, "phy");
  53         if (am_phy->id < 0) {
  54                 dev_err(&pdev->dev, "Missing PHY id: %d\n", am_phy->id);
  55                 return am_phy->id;
  56         }
  57
  58         am_phy->dr_mode = of_usb_get_dr_mode_by_phy(pdev->dev.of_node, -1);
  59
  60         ret = usb_phy_gen_create_phy(dev, &am_phy->usb_phy_gen, NULL);
  61         if (ret)
  62                 return ret;
  63
  64         ret = usb_add_phy_dev(&am_phy->usb_phy_gen.phy);
  65         if (ret)
  66                 return ret;
  67         am_phy->usb_phy_gen.phy.init = am335x_init;
  68         am_phy->usb_phy_gen.phy.shutdown = am335x_shutdown;
  69
  70         platform_set_drvdata(pdev, am_phy);
  71         device_init_wakeup(dev, true);
  72
  73         /*
  74          * If we leave PHY wakeup enabled then AM33XX wakes up
  75          * immediately from DS0. To avoid this we mark dev->power.can_wakeup
  76          * to false. The same is checked in suspend routine to decide
  77          * on whether to enable PHY wakeup or not.
  78          * PHY wakeup works fine in standby mode, there by allowing us to
  79          * handle remote wakeup, wakeup on disconnect and connect.
  80          */
  81
  82         device_set_wakeup_enable(dev, false);
  83         phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
  84
  85         return 0;
  86 }
  87
  88 static int am335x_phy_remove(struct platform_device *pdev)
  89 {
  90         struct am335x_phy *am_phy = platform_get_drvdata(pdev);
  91
  92         usb_remove_phy(&am_phy->usb_phy_gen.phy);
  93         return 0;
  94 }
  95
  96 #ifdef CONFIG_PM_SLEEP
  97 static int am335x_phy_suspend(struct device *dev)
  98 {
  99         struct platform_device  *pdev = to_platform_device(dev);
 100         struct am335x_phy *am_phy = platform_get_drvdata(pdev);
 101
 102         /*
 103          * Enable phy wakeup only if dev->power.can_wakeup is true.
 104          * Make sure to enable wakeup to support remote wakeup  in
 105          * standby mode ( same is not supported in OFF(DS0) mode).
 106          * Enable it by doing
 107          * echo enabled > /sys/bus/platform/devices/<usb-phy-id>/power/wakeup
 108          */
 109
 110         if (device_may_wakeup(dev))
 111                 phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, true);
 112
 113         phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
 114
 115         return 0;
 116 }
 117
 118 static int am335x_phy_resume(struct device *dev)
 119 {
 120         struct platform_device  *pdev = to_platform_device(dev);
 121         struct am335x_phy       *am_phy = platform_get_drvdata(pdev);
 122
 123         phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
 124
 125         if (device_may_wakeup(dev))
 126                 phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, false);
 127
 128         return 0;
 129 }
 130 #endif
 131
 132 static SIMPLE_DEV_PM_OPS(am335x_pm_ops, am335x_phy_suspend, am335x_phy_resume);
 133
 134 static const struct of_device_id am335x_phy_ids[] = {
 135         { .compatible = "ti,am335x-usb-phy" },
 136         { }
 137 };
 138 MODULE_DEVICE_TABLE(of, am335x_phy_ids);
 139
 140 static struct platform_driver am335x_phy_driver = {
 141         .probe          = am335x_phy_probe,
 142         .remove         = am335x_phy_remove,
 143         .driver         = {
 144                 .name   = "am335x-phy-driver",
 145                 .pm = &am335x_pm_ops,
 146                 .of_match_table = am335x_phy_ids,
 147         },
 148 };
 149
 150 module_platform_driver(am335x_phy_driver);
 151 MODULE_LICENSE("GPL v2");