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         am_phy->usb_phy_gen.phy.init = am335x_init;
  65         am_phy->usb_phy_gen.phy.shutdown = am335x_shutdown;
  66
  67         platform_set_drvdata(pdev, am_phy);
  68         device_init_wakeup(dev, true);
  69
  70         /*
  71          * If we leave PHY wakeup enabled then AM33XX wakes up
  72          * immediately from DS0. To avoid this we mark dev->power.can_wakeup
  73          * to false. The same is checked in suspend routine to decide
  74          * on whether to enable PHY wakeup or not.
  75          * PHY wakeup works fine in standby mode, there by allowing us to
  76          * handle remote wakeup, wakeup on disconnect and connect.
  77          */
  78
  79         device_set_wakeup_enable(dev, false);
  80         phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
  81
  82         return usb_add_phy_dev(&am_phy->usb_phy_gen.phy);
  83 }
  84
  85 static int am335x_phy_remove(struct platform_device *pdev)
  86 {
  87         struct am335x_phy *am_phy = platform_get_drvdata(pdev);
  88
  89         usb_remove_phy(&am_phy->usb_phy_gen.phy);
  90         return 0;
  91 }
  92
  93 #ifdef CONFIG_PM_SLEEP
  94 static int am335x_phy_suspend(struct device *dev)
  95 {
  96         struct am335x_phy *am_phy = dev_get_drvdata(dev);
  97
  98         /*
  99          * Enable phy wakeup only if dev->power.can_wakeup is true.
 100          * Make sure to enable wakeup to support remote wakeup  in
 101          * standby mode ( same is not supported in OFF(DS0) mode).
 102          * Enable it by doing
 103          * echo enabled > /sys/bus/platform/devices/<usb-phy-id>/power/wakeup
 104          */
 105
 106         if (device_may_wakeup(dev))
 107                 phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, true);
 108
 109         phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
 110
 111         return 0;
 112 }
 113
 114 static int am335x_phy_resume(struct device *dev)
 115 {
 116         struct am335x_phy       *am_phy = dev_get_drvdata(dev);
 117
 118         phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
 119
 120         if (device_may_wakeup(dev))
 121                 phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, false);
 122
 123         return 0;
 124 }
 125 #endif
 126
 127 static SIMPLE_DEV_PM_OPS(am335x_pm_ops, am335x_phy_suspend, am335x_phy_resume);
 128
 129 static const struct of_device_id am335x_phy_ids[] = {
 130         { .compatible = "ti,am335x-usb-phy" },
 131         { }
 132 };
 133 MODULE_DEVICE_TABLE(of, am335x_phy_ids);
 134
 135 static struct platform_driver am335x_phy_driver = {
 136         .probe          = am335x_phy_probe,
 137         .remove         = am335x_phy_remove,
 138         .driver         = {
 139                 .name   = "am335x-phy-driver",
 140                 .pm = &am335x_pm_ops,
 141                 .of_match_table = am335x_phy_ids,
 142         },
 143 };
 144
 145 module_platform_driver(am335x_phy_driver);
 146 MODULE_LICENSE("GPL v2");