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v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Cadence USBSS and USBSSP DRD Driver.
  4 *
  5 * Copyright (C) 2018-2020 Cadence.
  6 * Copyright (C) 2019 Texas Instruments
  7 *
  8 * Author: Pawel Laszczak <pawell@cadence.com>
  9 *         Roger Quadros <rogerq@ti.com>
 10 *
 
 11 */
 12#include <linux/kernel.h>
 13#include <linux/interrupt.h>
 14#include <linux/delay.h>
 15#include <linux/iopoll.h>
 16#include <linux/usb/otg.h>
 17
 
 18#include "drd.h"
 19#include "core.h"
 20
 21/**
 22 * cdns_set_mode - change mode of OTG Core
 23 * @cdns: pointer to context structure
 24 * @mode: selected mode from cdns_role
 25 *
 26 * Returns 0 on success otherwise negative errno
 27 */
 28static int cdns_set_mode(struct cdns *cdns, enum usb_dr_mode mode)
 29{
 30	void __iomem  *override_reg;
 31	u32 reg;
 32
 33	switch (mode) {
 34	case USB_DR_MODE_PERIPHERAL:
 35		break;
 36	case USB_DR_MODE_HOST:
 37		break;
 38	case USB_DR_MODE_OTG:
 39		dev_dbg(cdns->dev, "Set controller to OTG mode\n");
 40
 41		if (cdns->version == CDNSP_CONTROLLER_V2)
 42			override_reg = &cdns->otg_cdnsp_regs->override;
 43		else if (cdns->version == CDNS3_CONTROLLER_V1)
 44			override_reg = &cdns->otg_v1_regs->override;
 45		else
 46			override_reg = &cdns->otg_v0_regs->ctrl1;
 47
 48		reg = readl(override_reg);
 49
 50		if (cdns->version != CDNS3_CONTROLLER_V0)
 51			reg |= OVERRIDE_IDPULLUP;
 52		else
 
 
 53			reg |= OVERRIDE_IDPULLUP_V0;
 54
 55		writel(reg, override_reg);
 56
 57		if (cdns->version == CDNS3_CONTROLLER_V1) {
 58			/*
 59			 * Enable work around feature built into the
 60			 * controller to address issue with RX Sensitivity
 61			 * est (EL_17) for USB2 PHY. The issue only occures
 62			 * for 0x0002450D controller version.
 63			 */
 64			if (cdns->phyrst_a_enable) {
 65				reg = readl(&cdns->otg_v1_regs->phyrst_cfg);
 66				reg |= PHYRST_CFG_PHYRST_A_ENABLE;
 67				writel(reg, &cdns->otg_v1_regs->phyrst_cfg);
 68			}
 69		}
 70
 71		/*
 72		 * Hardware specification says: "ID_VALUE must be valid within
 73		 * 50ms after idpullup is set to '1" so driver must wait
 74		 * 50ms before reading this pin.
 75		 */
 76		usleep_range(50000, 60000);
 77		break;
 78	default:
 79		dev_err(cdns->dev, "Unsupported mode of operation %d\n", mode);
 80		return -EINVAL;
 81	}
 82
 83	return 0;
 84}
 85
 86int cdns_get_id(struct cdns *cdns)
 87{
 88	int id;
 89
 90	id = readl(&cdns->otg_regs->sts) & OTGSTS_ID_VALUE;
 91	dev_dbg(cdns->dev, "OTG ID: %d", id);
 92
 93	return id;
 94}
 95
 96int cdns_get_vbus(struct cdns *cdns)
 97{
 98	int vbus;
 99
100	vbus = !!(readl(&cdns->otg_regs->sts) & OTGSTS_VBUS_VALID);
101	dev_dbg(cdns->dev, "OTG VBUS: %d", vbus);
102
103	return vbus;
104}
105
106void cdns_clear_vbus(struct cdns *cdns)
107{
108	u32 reg;
109
110	if (cdns->version != CDNSP_CONTROLLER_V2)
111		return;
112
113	reg = readl(&cdns->otg_cdnsp_regs->override);
114	reg |= OVERRIDE_SESS_VLD_SEL;
115	writel(reg, &cdns->otg_cdnsp_regs->override);
116}
117EXPORT_SYMBOL_GPL(cdns_clear_vbus);
118
119void cdns_set_vbus(struct cdns *cdns)
120{
121	u32 reg;
122
123	if (cdns->version != CDNSP_CONTROLLER_V2)
124		return;
125
126	reg = readl(&cdns->otg_cdnsp_regs->override);
127	reg &= ~OVERRIDE_SESS_VLD_SEL;
128	writel(reg, &cdns->otg_cdnsp_regs->override);
129}
130EXPORT_SYMBOL_GPL(cdns_set_vbus);
131
132bool cdns_is_host(struct cdns *cdns)
133{
134	if (cdns->dr_mode == USB_DR_MODE_HOST)
135		return true;
136	else if (cdns_get_id(cdns) == CDNS3_ID_HOST)
137		return true;
138
139	return false;
140}
141
142bool cdns_is_device(struct cdns *cdns)
143{
144	if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL)
145		return true;
146	else if (cdns->dr_mode == USB_DR_MODE_OTG)
147		if (cdns_get_id(cdns) == CDNS3_ID_PERIPHERAL)
148			return true;
149
150	return false;
151}
152
153/**
154 * cdns_otg_disable_irq - Disable all OTG interrupts
155 * @cdns: Pointer to controller context structure
156 */
157static void cdns_otg_disable_irq(struct cdns *cdns)
158{
159	if (cdns->version)
160		writel(0, &cdns->otg_irq_regs->ien);
161}
162
163/**
164 * cdns_otg_enable_irq - enable id and sess_valid interrupts
165 * @cdns: Pointer to controller context structure
166 */
167static void cdns_otg_enable_irq(struct cdns *cdns)
168{
169	writel(OTGIEN_ID_CHANGE_INT | OTGIEN_VBUSVALID_RISE_INT |
170	       OTGIEN_VBUSVALID_FALL_INT, &cdns->otg_irq_regs->ien);
171}
172
173/**
174 * cdns_drd_host_on - start host.
175 * @cdns: Pointer to controller context structure.
 
176 *
177 * Returns 0 on success otherwise negative errno.
178 */
179int cdns_drd_host_on(struct cdns *cdns)
180{
181	u32 val, ready_bit;
182	int ret;
183
184	/* Enable host mode. */
185	writel(OTGCMD_HOST_BUS_REQ | OTGCMD_OTG_DIS,
186	       &cdns->otg_regs->cmd);
187
188	if (cdns->version == CDNSP_CONTROLLER_V2)
189		ready_bit = OTGSTS_CDNSP_XHCI_READY;
190	else
191		ready_bit = OTGSTS_CDNS3_XHCI_READY;
192
193	dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n");
194	ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
195					val & ready_bit, 1, 100000);
196
197	if (ret)
198		dev_err(cdns->dev, "timeout waiting for xhci_ready\n");
199
200	phy_set_mode(cdns->usb2_phy, PHY_MODE_USB_HOST);
201	phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_HOST);
202	return ret;
203}
204
205/**
206 * cdns_drd_host_off - stop host.
207 * @cdns: Pointer to controller context structure.
208 */
209void cdns_drd_host_off(struct cdns *cdns)
210{
211	u32 val;
 
 
 
 
 
 
 
 
 
 
212
213	writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
214	       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
215	       &cdns->otg_regs->cmd);
216
217	/* Waiting till H_IDLE state.*/
218	readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
219				  !(val & OTGSTATE_HOST_STATE_MASK),
220				  1, 2000000);
221	phy_set_mode(cdns->usb2_phy, PHY_MODE_INVALID);
222	phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID);
223}
224
225/**
226 * cdns_drd_gadget_on - start gadget.
227 * @cdns: Pointer to controller context structure.
 
228 *
229 * Returns 0 on success otherwise negative errno
230 */
231int cdns_drd_gadget_on(struct cdns *cdns)
232{
233	u32 reg = OTGCMD_OTG_DIS;
234	u32 ready_bit;
235	int ret, val;
 
236
237	/* switch OTG core */
238	writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd);
 
239
240	dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n");
241
242	if (cdns->version == CDNSP_CONTROLLER_V2)
243		ready_bit = OTGSTS_CDNSP_DEV_READY;
244	else
245		ready_bit = OTGSTS_CDNS3_DEV_READY;
246
247	ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
248					val & ready_bit, 1, 100000);
249	if (ret) {
250		dev_err(cdns->dev, "timeout waiting for dev_ready\n");
251		return ret;
 
 
 
 
 
 
 
 
 
 
252	}
253
254	phy_set_mode(cdns->usb2_phy, PHY_MODE_USB_DEVICE);
255	phy_set_mode(cdns->usb3_phy, PHY_MODE_USB_DEVICE);
256	return 0;
257}
258EXPORT_SYMBOL_GPL(cdns_drd_gadget_on);
259
260/**
261 * cdns_drd_gadget_off - stop gadget.
262 * @cdns: Pointer to controller context structure.
263 */
264void cdns_drd_gadget_off(struct cdns *cdns)
265{
266	u32 val;
267
268	/*
269	 * Driver should wait at least 10us after disabling Device
270	 * before turning-off Device (DEV_BUS_DROP).
271	 */
272	usleep_range(20, 30);
273	writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
274	       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
275	       &cdns->otg_regs->cmd);
276	/* Waiting till DEV_IDLE state.*/
277	readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
278				  !(val & OTGSTATE_DEV_STATE_MASK),
279				  1, 2000000);
280	phy_set_mode(cdns->usb2_phy, PHY_MODE_INVALID);
281	phy_set_mode(cdns->usb3_phy, PHY_MODE_INVALID);
282}
283EXPORT_SYMBOL_GPL(cdns_drd_gadget_off);
284
285/**
286 * cdns_init_otg_mode - initialize drd controller
287 * @cdns: Pointer to controller context structure
288 *
289 * Returns 0 on success otherwise negative errno
290 */
291static int cdns_init_otg_mode(struct cdns *cdns)
292{
293	int ret;
294
295	cdns_otg_disable_irq(cdns);
296	/* clear all interrupts */
297	writel(~0, &cdns->otg_irq_regs->ivect);
298
299	ret = cdns_set_mode(cdns, USB_DR_MODE_OTG);
300	if (ret)
301		return ret;
302
303	cdns_otg_enable_irq(cdns);
304
305	return 0;
306}
307
308/**
309 * cdns_drd_update_mode - initialize mode of operation
310 * @cdns: Pointer to controller context structure
311 *
312 * Returns 0 on success otherwise negative errno
313 */
314int cdns_drd_update_mode(struct cdns *cdns)
315{
316	int ret;
317
318	switch (cdns->dr_mode) {
319	case USB_DR_MODE_PERIPHERAL:
320		ret = cdns_set_mode(cdns, USB_DR_MODE_PERIPHERAL);
321		break;
322	case USB_DR_MODE_HOST:
323		ret = cdns_set_mode(cdns, USB_DR_MODE_HOST);
324		break;
325	case USB_DR_MODE_OTG:
326		ret = cdns_init_otg_mode(cdns);
327		break;
328	default:
329		dev_err(cdns->dev, "Unsupported mode of operation %d\n",
330			cdns->dr_mode);
331		return -EINVAL;
332	}
333
334	return ret;
335}
336
337static irqreturn_t cdns_drd_thread_irq(int irq, void *data)
338{
339	struct cdns *cdns = data;
340
341	cdns_hw_role_switch(cdns);
342
343	return IRQ_HANDLED;
344}
345
346/**
347 * cdns_drd_irq - interrupt handler for OTG events
348 *
349 * @irq: irq number for cdns core device
350 * @data: structure of cdns
351 *
352 * Returns IRQ_HANDLED or IRQ_NONE
353 */
354static irqreturn_t cdns_drd_irq(int irq, void *data)
355{
356	irqreturn_t ret = IRQ_NONE;
357	struct cdns *cdns = data;
358	u32 reg;
359
360	if (cdns->dr_mode != USB_DR_MODE_OTG)
361		return IRQ_NONE;
362
363	if (cdns->in_lpm)
364		return ret;
365
366	reg = readl(&cdns->otg_irq_regs->ivect);
367
368	if (!reg)
369		return IRQ_NONE;
370
371	if (reg & OTGIEN_ID_CHANGE_INT) {
372		dev_dbg(cdns->dev, "OTG IRQ: new ID: %d\n",
373			cdns_get_id(cdns));
374
375		ret = IRQ_WAKE_THREAD;
376	}
377
378	if (reg & (OTGIEN_VBUSVALID_RISE_INT | OTGIEN_VBUSVALID_FALL_INT)) {
379		dev_dbg(cdns->dev, "OTG IRQ: new VBUS: %d\n",
380			cdns_get_vbus(cdns));
381
382		ret = IRQ_WAKE_THREAD;
383	}
384
385	writel(~0, &cdns->otg_irq_regs->ivect);
386	return ret;
387}
388
389int cdns_drd_init(struct cdns *cdns)
390{
391	void __iomem *regs;
 
392	u32 state;
393	int ret;
394
395	regs = devm_ioremap_resource(cdns->dev, &cdns->otg_res);
396	if (IS_ERR(regs))
397		return PTR_ERR(regs);
398
399	/* Detection of DRD version. Controller has been released
400	 * in three versions. All are very similar and are software compatible,
401	 * but they have same changes in register maps.
402	 * The first register in oldest version is command register and it's
403	 * read only. Driver should read 0 from it. On the other hand, in v1
404	 * and v2 the first register contains device ID number which is not
405	 * set to 0. Driver uses this fact to detect the proper version of
406	 * controller.
407	 */
408	cdns->otg_v0_regs = regs;
409	if (!readl(&cdns->otg_v0_regs->cmd)) {
410		cdns->version  = CDNS3_CONTROLLER_V0;
411		cdns->otg_v1_regs = NULL;
412		cdns->otg_cdnsp_regs = NULL;
413		cdns->otg_regs = regs;
414		cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem  *)
415				     &cdns->otg_v0_regs->ien;
416		writel(1, &cdns->otg_v0_regs->simulate);
417		dev_dbg(cdns->dev, "DRD version v0 (%08x)\n",
418			 readl(&cdns->otg_v0_regs->version));
419	} else {
420		cdns->otg_v0_regs = NULL;
421		cdns->otg_v1_regs = regs;
422		cdns->otg_cdnsp_regs = regs;
423
424		cdns->otg_regs = (void __iomem *)&cdns->otg_v1_regs->cmd;
425
426		state = readl(&cdns->otg_cdnsp_regs->did);
427
428		if (OTG_CDNSP_CHECK_DID(state)) {
429			cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *)
430					      &cdns->otg_cdnsp_regs->ien;
431			cdns->version  = CDNSP_CONTROLLER_V2;
432		} else if (OTG_CDNS3_CHECK_DID(state)) {
433			cdns->otg_irq_regs = (struct cdns_otg_irq_regs __iomem *)
434					      &cdns->otg_v1_regs->ien;
435			writel(1, &cdns->otg_v1_regs->simulate);
436			cdns->version  = CDNS3_CONTROLLER_V1;
437		} else {
438			dev_err(cdns->dev, "not supporte DID=0x%08x\n", state);
439			return -EINVAL;
440		}
441
442		dev_dbg(cdns->dev, "DRD version v1 (ID: %08x, rev: %08x)\n",
443			 readl(&cdns->otg_v1_regs->did),
444			 readl(&cdns->otg_v1_regs->rid));
445	}
446
447	state = OTGSTS_STRAP(readl(&cdns->otg_regs->sts));
448
449	/* Update dr_mode according to STRAP configuration. */
450	cdns->dr_mode = USB_DR_MODE_OTG;
451
452	if ((cdns->version == CDNSP_CONTROLLER_V2 &&
453	     state == OTGSTS_CDNSP_STRAP_HOST) ||
454	    (cdns->version != CDNSP_CONTROLLER_V2 &&
455	     state == OTGSTS_STRAP_HOST)) {
456		dev_dbg(cdns->dev, "Controller strapped to HOST\n");
457		cdns->dr_mode = USB_DR_MODE_HOST;
458	} else if ((cdns->version == CDNSP_CONTROLLER_V2 &&
459		    state == OTGSTS_CDNSP_STRAP_GADGET) ||
460		   (cdns->version != CDNSP_CONTROLLER_V2 &&
461		    state == OTGSTS_STRAP_GADGET)) {
462		dev_dbg(cdns->dev, "Controller strapped to PERIPHERAL\n");
463		cdns->dr_mode = USB_DR_MODE_PERIPHERAL;
464	}
465
466	ret = devm_request_threaded_irq(cdns->dev, cdns->otg_irq,
467					cdns_drd_irq,
468					cdns_drd_thread_irq,
469					IRQF_SHARED,
470					dev_name(cdns->dev), cdns);
 
471	if (ret) {
472		dev_err(cdns->dev, "couldn't get otg_irq\n");
473		return ret;
474	}
475
476	state = readl(&cdns->otg_regs->sts);
477	if (OTGSTS_OTG_NRDY(state)) {
478		dev_err(cdns->dev, "Cadence USB3 OTG device not ready\n");
479		return -ENODEV;
480	}
481
482	return 0;
483}
484
485int cdns_drd_exit(struct cdns *cdns)
486{
487	cdns_otg_disable_irq(cdns);
488
489	return 0;
490}
491
492/* Indicate the cdns3 core was power lost before */
493bool cdns_power_is_lost(struct cdns *cdns)
494{
495	if (cdns->version == CDNS3_CONTROLLER_V0) {
496		if (!(readl(&cdns->otg_v0_regs->simulate) & BIT(0)))
497			return true;
498	} else {
499		if (!(readl(&cdns->otg_v1_regs->simulate) & BIT(0)))
500			return true;
501	}
502	return false;
503}
504EXPORT_SYMBOL_GPL(cdns_power_is_lost);
v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Cadence USBSS DRD Driver.
  4 *
  5 * Copyright (C) 2018-2019 Cadence.
  6 * Copyright (C) 2019 Texas Instruments
  7 *
  8 * Author: Pawel Laszczak <pawell@cadence.com>
  9 *         Roger Quadros <rogerq@ti.com>
 10 *
 11 *
 12 */
 13#include <linux/kernel.h>
 14#include <linux/interrupt.h>
 15#include <linux/delay.h>
 16#include <linux/iopoll.h>
 17#include <linux/usb/otg.h>
 18
 19#include "gadget.h"
 20#include "drd.h"
 21#include "core.h"
 22
 23/**
 24 * cdns3_set_mode - change mode of OTG Core
 25 * @cdns: pointer to context structure
 26 * @mode: selected mode from cdns_role
 27 *
 28 * Returns 0 on success otherwise negative errno
 29 */
 30int cdns3_set_mode(struct cdns3 *cdns, enum usb_dr_mode mode)
 31{
 32	int ret = 0;
 33	u32 reg;
 34
 35	switch (mode) {
 36	case USB_DR_MODE_PERIPHERAL:
 37		break;
 38	case USB_DR_MODE_HOST:
 39		break;
 40	case USB_DR_MODE_OTG:
 41		dev_dbg(cdns->dev, "Set controller to OTG mode\n");
 42		if (cdns->version == CDNS3_CONTROLLER_V1) {
 43			reg = readl(&cdns->otg_v1_regs->override);
 
 
 
 
 
 
 
 
 
 44			reg |= OVERRIDE_IDPULLUP;
 45			writel(reg, &cdns->otg_v1_regs->override);
 46		} else {
 47			reg = readl(&cdns->otg_v0_regs->ctrl1);
 48			reg |= OVERRIDE_IDPULLUP_V0;
 49			writel(reg, &cdns->otg_v0_regs->ctrl1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 50		}
 51
 52		/*
 53		 * Hardware specification says: "ID_VALUE must be valid within
 54		 * 50ms after idpullup is set to '1" so driver must wait
 55		 * 50ms before reading this pin.
 56		 */
 57		usleep_range(50000, 60000);
 58		break;
 59	default:
 60		dev_err(cdns->dev, "Unsupported mode of operation %d\n", mode);
 61		return -EINVAL;
 62	}
 63
 64	return ret;
 65}
 66
 67int cdns3_get_id(struct cdns3 *cdns)
 68{
 69	int id;
 70
 71	id = readl(&cdns->otg_regs->sts) & OTGSTS_ID_VALUE;
 72	dev_dbg(cdns->dev, "OTG ID: %d", id);
 73
 74	return id;
 75}
 76
 77int cdns3_get_vbus(struct cdns3 *cdns)
 78{
 79	int vbus;
 80
 81	vbus = !!(readl(&cdns->otg_regs->sts) & OTGSTS_VBUS_VALID);
 82	dev_dbg(cdns->dev, "OTG VBUS: %d", vbus);
 83
 84	return vbus;
 85}
 86
 87int cdns3_is_host(struct cdns3 *cdns)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 88{
 89	if (cdns->dr_mode == USB_DR_MODE_HOST)
 90		return 1;
 91	else if (!cdns3_get_id(cdns))
 92		return 1;
 93
 94	return 0;
 95}
 96
 97int cdns3_is_device(struct cdns3 *cdns)
 98{
 99	if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL)
100		return 1;
101	else if (cdns->dr_mode == USB_DR_MODE_OTG)
102		if (cdns3_get_id(cdns))
103			return 1;
104
105	return 0;
106}
107
108/**
109 * cdns3_otg_disable_irq - Disable all OTG interrupts
110 * @cdns: Pointer to controller context structure
111 */
112static void cdns3_otg_disable_irq(struct cdns3 *cdns)
113{
114	writel(0, &cdns->otg_regs->ien);
 
115}
116
117/**
118 * cdns3_otg_enable_irq - enable id and sess_valid interrupts
119 * @cdns: Pointer to controller context structure
120 */
121static void cdns3_otg_enable_irq(struct cdns3 *cdns)
122{
123	writel(OTGIEN_ID_CHANGE_INT | OTGIEN_VBUSVALID_RISE_INT |
124	       OTGIEN_VBUSVALID_FALL_INT, &cdns->otg_regs->ien);
125}
126
127/**
128 * cdns3_drd_switch_host - start/stop host
129 * @cdns: Pointer to controller context structure
130 * @on: 1 for start, 0 for stop
131 *
132 * Returns 0 on success otherwise negative errno
133 */
134int cdns3_drd_switch_host(struct cdns3 *cdns, int on)
135{
136	int ret, val;
137	u32 reg = OTGCMD_OTG_DIS;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
138
139	/* switch OTG core */
140	if (on) {
141		writel(OTGCMD_HOST_BUS_REQ | reg, &cdns->otg_regs->cmd);
 
142
143		dev_dbg(cdns->dev, "Waiting till Host mode is turned on\n");
144		ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
145						val & OTGSTS_XHCI_READY,
146						1, 100000);
147		if (ret) {
148			dev_err(cdns->dev, "timeout waiting for xhci_ready\n");
149			return ret;
150		}
151	} else {
152		writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
153		       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
154		       &cdns->otg_regs->cmd);
155		/* Waiting till H_IDLE state.*/
156		readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
157					  !(val & OTGSTATE_HOST_STATE_MASK),
158					  1, 2000000);
159	}
160
161	return 0;
 
 
 
 
 
 
 
 
 
162}
163
164/**
165 * cdns3_drd_switch_gadget - start/stop gadget
166 * @cdns: Pointer to controller context structure
167 * @on: 1 for start, 0 for stop
168 *
169 * Returns 0 on success otherwise negative errno
170 */
171int cdns3_drd_switch_gadget(struct cdns3 *cdns, int on)
172{
 
 
173	int ret, val;
174	u32 reg = OTGCMD_OTG_DIS;
175
176	/* switch OTG core */
177	if (on) {
178		writel(OTGCMD_DEV_BUS_REQ | reg, &cdns->otg_regs->cmd);
179
180		dev_dbg(cdns->dev, "Waiting till Device mode is turned on\n");
181
182		ret = readl_poll_timeout_atomic(&cdns->otg_regs->sts, val,
183						val & OTGSTS_DEV_READY,
184						1, 100000);
185		if (ret) {
186			dev_err(cdns->dev, "timeout waiting for dev_ready\n");
187			return ret;
188		}
189	} else {
190		/*
191		 * driver should wait at least 10us after disabling Device
192		 * before turning-off Device (DEV_BUS_DROP)
193		 */
194		usleep_range(20, 30);
195		writel(OTGCMD_HOST_BUS_DROP | OTGCMD_DEV_BUS_DROP |
196		       OTGCMD_DEV_POWER_OFF | OTGCMD_HOST_POWER_OFF,
197		       &cdns->otg_regs->cmd);
198		/* Waiting till DEV_IDLE state.*/
199		readl_poll_timeout_atomic(&cdns->otg_regs->state, val,
200					  !(val & OTGSTATE_DEV_STATE_MASK),
201					  1, 2000000);
202	}
203
 
 
204	return 0;
205}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
206
207/**
208 * cdns3_init_otg_mode - initialize drd controller
209 * @cdns: Pointer to controller context structure
210 *
211 * Returns 0 on success otherwise negative errno
212 */
213static int cdns3_init_otg_mode(struct cdns3 *cdns)
214{
215	int ret = 0;
216
217	cdns3_otg_disable_irq(cdns);
218	/* clear all interrupts */
219	writel(~0, &cdns->otg_regs->ivect);
220
221	ret = cdns3_set_mode(cdns, USB_DR_MODE_OTG);
222	if (ret)
223		return ret;
224
225	cdns3_otg_enable_irq(cdns);
226	return ret;
 
227}
228
229/**
230 * cdns3_drd_update_mode - initialize mode of operation
231 * @cdns: Pointer to controller context structure
232 *
233 * Returns 0 on success otherwise negative errno
234 */
235int cdns3_drd_update_mode(struct cdns3 *cdns)
236{
237	int ret = 0;
238
239	switch (cdns->dr_mode) {
240	case USB_DR_MODE_PERIPHERAL:
241		ret = cdns3_set_mode(cdns, USB_DR_MODE_PERIPHERAL);
242		break;
243	case USB_DR_MODE_HOST:
244		ret = cdns3_set_mode(cdns, USB_DR_MODE_HOST);
245		break;
246	case USB_DR_MODE_OTG:
247		ret = cdns3_init_otg_mode(cdns);
248		break;
249	default:
250		dev_err(cdns->dev, "Unsupported mode of operation %d\n",
251			cdns->dr_mode);
252		return -EINVAL;
253	}
254
255	return ret;
256}
257
258static irqreturn_t cdns3_drd_thread_irq(int irq, void *data)
259{
260	struct cdns3 *cdns = data;
261
262	cdns3_hw_role_switch(cdns);
263
264	return IRQ_HANDLED;
265}
266
267/**
268 * cdns3_drd_irq - interrupt handler for OTG events
269 *
270 * @irq: irq number for cdns3 core device
271 * @data: structure of cdns3
272 *
273 * Returns IRQ_HANDLED or IRQ_NONE
274 */
275static irqreturn_t cdns3_drd_irq(int irq, void *data)
276{
277	irqreturn_t ret = IRQ_NONE;
278	struct cdns3 *cdns = data;
279	u32 reg;
280
281	if (cdns->dr_mode != USB_DR_MODE_OTG)
 
 
 
282		return ret;
283
284	reg = readl(&cdns->otg_regs->ivect);
285
286	if (!reg)
287		return ret;
288
289	if (reg & OTGIEN_ID_CHANGE_INT) {
290		dev_dbg(cdns->dev, "OTG IRQ: new ID: %d\n",
291			cdns3_get_id(cdns));
292
293		ret = IRQ_WAKE_THREAD;
294	}
295
296	if (reg & (OTGIEN_VBUSVALID_RISE_INT | OTGIEN_VBUSVALID_FALL_INT)) {
297		dev_dbg(cdns->dev, "OTG IRQ: new VBUS: %d\n",
298			cdns3_get_vbus(cdns));
299
300		ret = IRQ_WAKE_THREAD;
301	}
302
303	writel(~0, &cdns->otg_regs->ivect);
304	return ret;
305}
306
307int cdns3_drd_init(struct cdns3 *cdns)
308{
309	void __iomem *regs;
310	int ret = 0;
311	u32 state;
 
312
313	regs = devm_ioremap_resource(cdns->dev, &cdns->otg_res);
314	if (IS_ERR(regs))
315		return PTR_ERR(regs);
316
317	/* Detection of DRD version. Controller has been released
318	 * in two versions. Both are similar, but they have same changes
319	 * in register maps.
320	 * The first register in old version is command register and it's read
321	 * only, so driver should read 0 from it. On the other hand, in v1
322	 * the first register contains device ID number which is not set to 0.
323	 * Driver uses this fact to detect the proper version of
324	 * controller.
325	 */
326	cdns->otg_v0_regs = regs;
327	if (!readl(&cdns->otg_v0_regs->cmd)) {
328		cdns->version  = CDNS3_CONTROLLER_V0;
329		cdns->otg_v1_regs = NULL;
 
330		cdns->otg_regs = regs;
 
 
331		writel(1, &cdns->otg_v0_regs->simulate);
332		dev_info(cdns->dev, "DRD version v0 (%08x)\n",
333			 readl(&cdns->otg_v0_regs->version));
334	} else {
335		cdns->otg_v0_regs = NULL;
336		cdns->otg_v1_regs = regs;
337		cdns->otg_regs = (void *)&cdns->otg_v1_regs->cmd;
338		cdns->version  = CDNS3_CONTROLLER_V1;
339		writel(1, &cdns->otg_v1_regs->simulate);
340		dev_info(cdns->dev, "DRD version v1 (ID: %08x, rev: %08x)\n",
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
341			 readl(&cdns->otg_v1_regs->did),
342			 readl(&cdns->otg_v1_regs->rid));
343	}
344
345	state = OTGSTS_STRAP(readl(&cdns->otg_regs->sts));
346
347	/* Update dr_mode according to STRAP configuration. */
348	cdns->dr_mode = USB_DR_MODE_OTG;
349	if (state == OTGSTS_STRAP_HOST) {
 
 
 
 
350		dev_dbg(cdns->dev, "Controller strapped to HOST\n");
351		cdns->dr_mode = USB_DR_MODE_HOST;
352	} else if (state == OTGSTS_STRAP_GADGET) {
 
 
 
353		dev_dbg(cdns->dev, "Controller strapped to PERIPHERAL\n");
354		cdns->dr_mode = USB_DR_MODE_PERIPHERAL;
355	}
356
357	ret = devm_request_threaded_irq(cdns->dev, cdns->otg_irq,
358					cdns3_drd_irq,
359					cdns3_drd_thread_irq,
360					IRQF_SHARED,
361					dev_name(cdns->dev), cdns);
362
363	if (ret) {
364		dev_err(cdns->dev, "couldn't get otg_irq\n");
365		return ret;
366	}
367
368	state = readl(&cdns->otg_regs->sts);
369	if (OTGSTS_OTG_NRDY(state) != 0) {
370		dev_err(cdns->dev, "Cadence USB3 OTG device not ready\n");
371		return -ENODEV;
372	}
373
374	return ret;
375}
376
377int cdns3_drd_exit(struct cdns3 *cdns)
378{
379	cdns3_otg_disable_irq(cdns);
 
380	return 0;
381}