1/*
  2 * Provides code common for host and device side USB.
  3 *
  4 * This program is free software; you can redistribute it and/or
  5 * modify it under the terms of the GNU General Public License as
  6 * published by the Free Software Foundation, version 2.
  7 *
  8 * If either host side (ie. CONFIG_USB=y) or device side USB stack
  9 * (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is
 10 * compiled-in as well.  Otherwise, if either of the two stacks is
 11 * compiled as module, this file is compiled as module as well.
 12 */
 13
 14#include <linux/kernel.h>
 15#include <linux/module.h>
 16#include <linux/of.h>
 17#include <linux/usb/ch9.h>
 18#include <linux/usb/of.h>
 19#include <linux/usb/otg.h>
 20#include <linux/of_platform.h>
 21
 22const char *usb_otg_state_string(enum usb_otg_state state)
 23{
 24	static const char *const names[] = {
 25		[OTG_STATE_A_IDLE] = "a_idle",
 26		[OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
 27		[OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
 28		[OTG_STATE_A_HOST] = "a_host",
 29		[OTG_STATE_A_SUSPEND] = "a_suspend",
 30		[OTG_STATE_A_PERIPHERAL] = "a_peripheral",
 31		[OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
 32		[OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
 33		[OTG_STATE_B_IDLE] = "b_idle",
 34		[OTG_STATE_B_SRP_INIT] = "b_srp_init",
 35		[OTG_STATE_B_PERIPHERAL] = "b_peripheral",
 36		[OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
 37		[OTG_STATE_B_HOST] = "b_host",
 38	};
 39
 40	if (state < 0 || state >= ARRAY_SIZE(names))
 41		return "UNDEFINED";
 42
 43	return names[state];
 44}
 45EXPORT_SYMBOL_GPL(usb_otg_state_string);
 46
 47static const char *const speed_names[] = {
 48	[USB_SPEED_UNKNOWN] = "UNKNOWN",
 49	[USB_SPEED_LOW] = "low-speed",
 50	[USB_SPEED_FULL] = "full-speed",
 51	[USB_SPEED_HIGH] = "high-speed",
 52	[USB_SPEED_WIRELESS] = "wireless",
 53	[USB_SPEED_SUPER] = "super-speed",
 54	[USB_SPEED_SUPER_PLUS] = "super-speed-plus",
 55};
 56
 57const char *usb_speed_string(enum usb_device_speed speed)
 58{
 59	if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
 60		speed = USB_SPEED_UNKNOWN;
 61	return speed_names[speed];
 62}
 63EXPORT_SYMBOL_GPL(usb_speed_string);
 64
 65enum usb_device_speed usb_get_maximum_speed(struct device *dev)
 66{
 67	const char *maximum_speed;
 68	int ret;
 69
 70	ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
 71	if (ret < 0)
 72		return USB_SPEED_UNKNOWN;
 73
 74	ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
 75
 76	return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
 77}
 78EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
 79
 80const char *usb_state_string(enum usb_device_state state)
 81{
 82	static const char *const names[] = {
 83		[USB_STATE_NOTATTACHED] = "not attached",
 84		[USB_STATE_ATTACHED] = "attached",
 85		[USB_STATE_POWERED] = "powered",
 86		[USB_STATE_RECONNECTING] = "reconnecting",
 87		[USB_STATE_UNAUTHENTICATED] = "unauthenticated",
 88		[USB_STATE_DEFAULT] = "default",
 89		[USB_STATE_ADDRESS] = "addressed",
 90		[USB_STATE_CONFIGURED] = "configured",
 91		[USB_STATE_SUSPENDED] = "suspended",
 92	};
 93
 94	if (state < 0 || state >= ARRAY_SIZE(names))
 95		return "UNKNOWN";
 96
 97	return names[state];
 98}
 99EXPORT_SYMBOL_GPL(usb_state_string);
100
101static const char *const usb_dr_modes[] = {
102	[USB_DR_MODE_UNKNOWN]		= "",
103	[USB_DR_MODE_HOST]		= "host",
104	[USB_DR_MODE_PERIPHERAL]	= "peripheral",
105	[USB_DR_MODE_OTG]		= "otg",
106};
107
108static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
109{
110	int ret;
111
112	ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
113	return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
114}
115
116enum usb_dr_mode usb_get_dr_mode(struct device *dev)
117{
118	const char *dr_mode;
119	int err;
120
121	err = device_property_read_string(dev, "dr_mode", &dr_mode);
122	if (err < 0)
123		return USB_DR_MODE_UNKNOWN;
124
125	return usb_get_dr_mode_from_string(dr_mode);
126}
127EXPORT_SYMBOL_GPL(usb_get_dr_mode);
128
129#ifdef CONFIG_OF
130/**
131 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
132 * which is associated with the given phy device_node
133 * @np:	Pointer to the given phy device_node
134 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
135 *        phys which do not have phy-cells
136 *
137 * In dts a usb controller associates with phy devices.  The function gets
138 * the string from property 'dr_mode' of the controller associated with the
139 * given phy device node, and returns the correspondig enum usb_dr_mode.
140 */
141enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
142{
143	struct device_node *controller = NULL;
144	struct of_phandle_args args;
145	const char *dr_mode;
146	int index;
147	int err;
148
149	do {
150		controller = of_find_node_with_property(controller, "phys");
151		index = 0;
152		do {
153			if (arg0 == -1) {
154				args.np = of_parse_phandle(controller, "phys",
155							index);
156				args.args_count = 0;
157			} else {
158				err = of_parse_phandle_with_args(controller,
159							"phys", "#phy-cells",
160							index, &args);
161				if (err)
162					break;
163			}
164
165			of_node_put(args.np);
166			if (args.np == np && (args.args_count == 0 ||
167					      args.args[0] == arg0))
168				goto finish;
169			index++;
170		} while (args.np);
171	} while (controller);
172
173finish:
174	err = of_property_read_string(controller, "dr_mode", &dr_mode);
175	of_node_put(controller);
176
177	if (err < 0)
178		return USB_DR_MODE_UNKNOWN;
179
180	return usb_get_dr_mode_from_string(dr_mode);
181}
182EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
183
184/**
185 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
186 * for given targeted hosts (non-PC hosts)
187 * @np: Pointer to the given device_node
188 *
189 * The function gets if the targeted hosts support TPL or not
190 */
191bool of_usb_host_tpl_support(struct device_node *np)
192{
193	if (of_find_property(np, "tpl-support", NULL))
194		return true;
195
196	return false;
197}
198EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
199
200/**
201 * of_usb_update_otg_caps - to update usb otg capabilities according to
202 * the passed properties in DT.
203 * @np: Pointer to the given device_node
204 * @otg_caps: Pointer to the target usb_otg_caps to be set
205 *
206 * The function updates the otg capabilities
207 */
208int of_usb_update_otg_caps(struct device_node *np,
209			struct usb_otg_caps *otg_caps)
210{
211	u32 otg_rev;
212
213	if (!otg_caps)
214		return -EINVAL;
215
216	if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
217		switch (otg_rev) {
218		case 0x0100:
219		case 0x0120:
220		case 0x0130:
221		case 0x0200:
222			/* Choose the lesser one if it's already been set */
223			if (otg_caps->otg_rev)
224				otg_caps->otg_rev = min_t(u16, otg_rev,
225							otg_caps->otg_rev);
226			else
227				otg_caps->otg_rev = otg_rev;
228			break;
229		default:
230			pr_err("%s: unsupported otg-rev: 0x%x\n",
231						np->full_name, otg_rev);
232			return -EINVAL;
233		}
234	} else {
235		/*
236		 * otg-rev is mandatory for otg properties, if not passed
237		 * we set it to be 0 and assume it's a legacy otg device.
238		 * Non-dt platform can set it afterwards.
239		 */
240		otg_caps->otg_rev = 0;
241	}
242
243	if (of_find_property(np, "hnp-disable", NULL))
244		otg_caps->hnp_support = false;
245	if (of_find_property(np, "srp-disable", NULL))
246		otg_caps->srp_support = false;
247	if (of_find_property(np, "adp-disable", NULL) ||
248				(otg_caps->otg_rev < 0x0200))
249		otg_caps->adp_support = false;
250
251	return 0;
252}
253EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
254
255#endif
256
257MODULE_LICENSE("GPL");