// SPDX-License-Identifier: GPL-2.0
/*
* Provides code common for host and device side USB.
*
* If either host side (ie. CONFIG_USB=y) or device side USB stack
* (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is
* compiled-in as well. Otherwise, if either of the two stacks is
* compiled as module, this file is compiled as module as well.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/usb/ch9.h>
#include <linux/usb/of.h>
#include <linux/usb/otg.h>
#include <linux/of_platform.h>
#include <linux/debugfs.h>
#include "common.h"
static const char *const ep_type_names[] = {
[USB_ENDPOINT_XFER_CONTROL] = "ctrl",
[USB_ENDPOINT_XFER_ISOC] = "isoc",
[USB_ENDPOINT_XFER_BULK] = "bulk",
[USB_ENDPOINT_XFER_INT] = "intr",
};
/**
* usb_ep_type_string() - Returns human readable-name of the endpoint type.
* @ep_type: The endpoint type to return human-readable name for. If it's not
* any of the types: USB_ENDPOINT_XFER_{CONTROL, ISOC, BULK, INT},
* usually got by usb_endpoint_type(), the string 'unknown' will be returned.
*/
const char *usb_ep_type_string(int ep_type)
{
if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names))
return "unknown";
return ep_type_names[ep_type];
}
EXPORT_SYMBOL_GPL(usb_ep_type_string);
const char *usb_otg_state_string(enum usb_otg_state state)
{
static const char *const names[] = {
[OTG_STATE_A_IDLE] = "a_idle",
[OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
[OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
[OTG_STATE_A_HOST] = "a_host",
[OTG_STATE_A_SUSPEND] = "a_suspend",
[OTG_STATE_A_PERIPHERAL] = "a_peripheral",
[OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
[OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
[OTG_STATE_B_IDLE] = "b_idle",
[OTG_STATE_B_SRP_INIT] = "b_srp_init",
[OTG_STATE_B_PERIPHERAL] = "b_peripheral",
[OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
[OTG_STATE_B_HOST] = "b_host",
};
if (state < 0 || state >= ARRAY_SIZE(names))
return "UNDEFINED";
return names[state];
}
EXPORT_SYMBOL_GPL(usb_otg_state_string);
static const char *const speed_names[] = {
[USB_SPEED_UNKNOWN] = "UNKNOWN",
[USB_SPEED_LOW] = "low-speed",
[USB_SPEED_FULL] = "full-speed",
[USB_SPEED_HIGH] = "high-speed",
[USB_SPEED_WIRELESS] = "wireless",
[USB_SPEED_SUPER] = "super-speed",
[USB_SPEED_SUPER_PLUS] = "super-speed-plus",
};
static const char *const ssp_rate[] = {
[USB_SSP_GEN_UNKNOWN] = "UNKNOWN",
[USB_SSP_GEN_2x1] = "super-speed-plus-gen2x1",
[USB_SSP_GEN_1x2] = "super-speed-plus-gen1x2",
[USB_SSP_GEN_2x2] = "super-speed-plus-gen2x2",
};
/**
* usb_speed_string() - Returns human readable-name of the speed.
* @speed: The speed to return human-readable name for. If it's not
* any of the speeds defined in usb_device_speed enum, string for
* USB_SPEED_UNKNOWN will be returned.
*/
const char *usb_speed_string(enum usb_device_speed speed)
{
if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
speed = USB_SPEED_UNKNOWN;
return speed_names[speed];
}
EXPORT_SYMBOL_GPL(usb_speed_string);
/**
* usb_get_maximum_speed - Get maximum requested speed for a given USB
* controller.
* @dev: Pointer to the given USB controller device
*
* The function gets the maximum speed string from property "maximum-speed",
* and returns the corresponding enum usb_device_speed.
*/
enum usb_device_speed usb_get_maximum_speed(struct device *dev)
{
const char *p = "maximum-speed";
int ret;
ret = device_property_match_property_string(dev, p, ssp_rate, ARRAY_SIZE(ssp_rate));
if (ret > 0)
return USB_SPEED_SUPER_PLUS;
ret = device_property_match_property_string(dev, p, speed_names, ARRAY_SIZE(speed_names));
if (ret > 0)
return ret;
return USB_SPEED_UNKNOWN;
}
EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
/**
* usb_get_maximum_ssp_rate - Get the signaling rate generation and lane count
* of a SuperSpeed Plus capable device.
* @dev: Pointer to the given USB controller device
*
* If the string from "maximum-speed" property is super-speed-plus-genXxY where
* 'X' is the generation number and 'Y' is the number of lanes, then this
* function returns the corresponding enum usb_ssp_rate.
*/
enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev)
{
const char *maximum_speed;
int ret;
ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
if (ret < 0)
return USB_SSP_GEN_UNKNOWN;
ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret;
}
EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate);
/**
* usb_state_string - Returns human readable name for the state.
* @state: The state to return a human-readable name for. If it's not
* any of the states devices in usb_device_state_string enum,
* the string UNKNOWN will be returned.
*/
const char *usb_state_string(enum usb_device_state state)
{
static const char *const names[] = {
[USB_STATE_NOTATTACHED] = "not attached",
[USB_STATE_ATTACHED] = "attached",
[USB_STATE_POWERED] = "powered",
[USB_STATE_RECONNECTING] = "reconnecting",
[USB_STATE_UNAUTHENTICATED] = "unauthenticated",
[USB_STATE_DEFAULT] = "default",
[USB_STATE_ADDRESS] = "addressed",
[USB_STATE_CONFIGURED] = "configured",
[USB_STATE_SUSPENDED] = "suspended",
};
if (state < 0 || state >= ARRAY_SIZE(names))
return "UNKNOWN";
return names[state];
}
EXPORT_SYMBOL_GPL(usb_state_string);
static const char *const usb_dr_modes[] = {
[USB_DR_MODE_UNKNOWN] = "",
[USB_DR_MODE_HOST] = "host",
[USB_DR_MODE_PERIPHERAL] = "peripheral",
[USB_DR_MODE_OTG] = "otg",
};
static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
{
int ret;
ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
}
enum usb_dr_mode usb_get_dr_mode(struct device *dev)
{
const char *dr_mode;
int err;
err = device_property_read_string(dev, "dr_mode", &dr_mode);
if (err < 0)
return USB_DR_MODE_UNKNOWN;
return usb_get_dr_mode_from_string(dr_mode);
}
EXPORT_SYMBOL_GPL(usb_get_dr_mode);
/**
* usb_get_role_switch_default_mode - Get default mode for given device
* @dev: Pointer to the given device
*
* The function gets string from property 'role-switch-default-mode',
* and returns the corresponding enum usb_dr_mode.
*/
enum usb_dr_mode usb_get_role_switch_default_mode(struct device *dev)
{
const char *str;
int ret;
ret = device_property_read_string(dev, "role-switch-default-mode", &str);
if (ret < 0)
return USB_DR_MODE_UNKNOWN;
return usb_get_dr_mode_from_string(str);
}
EXPORT_SYMBOL_GPL(usb_get_role_switch_default_mode);
/**
* usb_decode_interval - Decode bInterval into the time expressed in 1us unit
* @epd: The descriptor of the endpoint
* @speed: The speed that the endpoint works as
*
* Function returns the interval expressed in 1us unit for servicing
* endpoint for data transfers.
*/
unsigned int usb_decode_interval(const struct usb_endpoint_descriptor *epd,
enum usb_device_speed speed)
{
unsigned int interval = 0;
switch (usb_endpoint_type(epd)) {
case USB_ENDPOINT_XFER_CONTROL:
/* uframes per NAK */
if (speed == USB_SPEED_HIGH)
interval = epd->bInterval;
break;
case USB_ENDPOINT_XFER_ISOC:
interval = 1 << (epd->bInterval - 1);
break;
case USB_ENDPOINT_XFER_BULK:
/* uframes per NAK */
if (speed == USB_SPEED_HIGH && usb_endpoint_dir_out(epd))
interval = epd->bInterval;
break;
case USB_ENDPOINT_XFER_INT:
if (speed >= USB_SPEED_HIGH)
interval = 1 << (epd->bInterval - 1);
else
interval = epd->bInterval;
break;
}
interval *= (speed >= USB_SPEED_HIGH) ? 125 : 1000;
return interval;
}
EXPORT_SYMBOL_GPL(usb_decode_interval);
#ifdef CONFIG_OF
/**
* of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
* which is associated with the given phy device_node
* @np: Pointer to the given phy device_node
* @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
* phys which do not have phy-cells
*
* In dts a usb controller associates with phy devices. The function gets
* the string from property 'dr_mode' of the controller associated with the
* given phy device node, and returns the correspondig enum usb_dr_mode.
*/
enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
{
struct device_node *controller;
struct of_phandle_args args;
const char *dr_mode;
int index;
int err;
for_each_node_with_property(controller, "phys") {
if (!of_device_is_available(controller))
continue;
index = 0;
do {
if (arg0 == -1) {
args.np = of_parse_phandle(controller, "phys",
index);
args.args_count = 0;
} else {
err = of_parse_phandle_with_args(controller,
"phys", "#phy-cells",
index, &args);
if (err)
break;
}
of_node_put(args.np);
if (args.np == np && (args.args_count == 0 ||
args.args[0] == arg0))
goto finish;
index++;
} while (args.np);
}
finish:
err = of_property_read_string(controller, "dr_mode", &dr_mode);
of_node_put(controller);
if (err < 0)
return USB_DR_MODE_UNKNOWN;
return usb_get_dr_mode_from_string(dr_mode);
}
EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
/**
* of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
* for given targeted hosts (non-PC hosts)
* @np: Pointer to the given device_node
*
* The function gets if the targeted hosts support TPL or not
*/
bool of_usb_host_tpl_support(struct device_node *np)
{
return of_property_read_bool(np, "tpl-support");
}
EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
/**
* of_usb_update_otg_caps - to update usb otg capabilities according to
* the passed properties in DT.
* @np: Pointer to the given device_node
* @otg_caps: Pointer to the target usb_otg_caps to be set
*
* The function updates the otg capabilities
*/
int of_usb_update_otg_caps(struct device_node *np,
struct usb_otg_caps *otg_caps)
{
u32 otg_rev;
if (!otg_caps)
return -EINVAL;
if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
switch (otg_rev) {
case 0x0100:
case 0x0120:
case 0x0130:
case 0x0200:
/* Choose the lesser one if it's already been set */
if (otg_caps->otg_rev)
otg_caps->otg_rev = min_t(u16, otg_rev,
otg_caps->otg_rev);
else
otg_caps->otg_rev = otg_rev;
break;
default:
pr_err("%pOF: unsupported otg-rev: 0x%x\n",
np, otg_rev);
return -EINVAL;
}
} else {
/*
* otg-rev is mandatory for otg properties, if not passed
* we set it to be 0 and assume it's a legacy otg device.
* Non-dt platform can set it afterwards.
*/
otg_caps->otg_rev = 0;
}
if (of_property_read_bool(np, "hnp-disable"))
otg_caps->hnp_support = false;
if (of_property_read_bool(np, "srp-disable"))
otg_caps->srp_support = false;
if (of_property_read_bool(np, "adp-disable") ||
(otg_caps->otg_rev < 0x0200))
otg_caps->adp_support = false;
return 0;
}
EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
/**
* usb_of_get_companion_dev - Find the companion device
* @dev: the device pointer to find a companion
*
* Find the companion device from platform bus.
*
* Takes a reference to the returned struct device which needs to be dropped
* after use.
*
* Return: On success, a pointer to the companion device, %NULL on failure.
*/
struct device *usb_of_get_companion_dev(struct device *dev)
{
struct device_node *node;
struct platform_device *pdev = NULL;
node = of_parse_phandle(dev->of_node, "companion", 0);
if (node)
pdev = of_find_device_by_node(node);
of_node_put(node);
return pdev ? &pdev->dev : NULL;
}
EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
#endif
struct dentry *usb_debug_root;
EXPORT_SYMBOL_GPL(usb_debug_root);
static int __init usb_common_init(void)
{
usb_debug_root = debugfs_create_dir("usb", NULL);
ledtrig_usb_init();
return 0;
}
static void __exit usb_common_exit(void)
{
ledtrig_usb_exit();
debugfs_remove_recursive(usb_debug_root);
}
subsys_initcall(usb_common_init);
module_exit(usb_common_exit);
MODULE_DESCRIPTION("Common code for host and device side USB");
MODULE_LICENSE("GPL");
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