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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Copyright 2015 IBM Corp.
   4 *
   5 * Joel Stanley <joel@jms.id.au>
   6 */
   7
   8#include <asm/div64.h>
   9#include <linux/clk.h>
  10#include <linux/gpio/driver.h>
  11#include <linux/gpio/aspeed.h>
  12#include <linux/hashtable.h>
  13#include <linux/init.h>
  14#include <linux/io.h>
  15#include <linux/kernel.h>
  16#include <linux/module.h>
  17#include <linux/pinctrl/consumer.h>
  18#include <linux/platform_device.h>
  19#include <linux/spinlock.h>
  20#include <linux/string.h>
  21
  22/*
  23 * These two headers aren't meant to be used by GPIO drivers. We need
  24 * them in order to access gpio_chip_hwgpio() which we need to implement
  25 * the aspeed specific API which allows the coprocessor to request
  26 * access to some GPIOs and to arbitrate between coprocessor and ARM.
  27 */
  28#include <linux/gpio/consumer.h>
  29#include "gpiolib.h"
  30
  31struct aspeed_bank_props {
  32	unsigned int bank;
  33	u32 input;
  34	u32 output;
  35};
  36
  37struct aspeed_gpio_config {
  38	unsigned int nr_gpios;
  39	const struct aspeed_bank_props *props;
  40};
  41
  42/*
  43 * @offset_timer: Maps an offset to an @timer_users index, or zero if disabled
  44 * @timer_users: Tracks the number of users for each timer
  45 *
  46 * The @timer_users has four elements but the first element is unused. This is
  47 * to simplify accounting and indexing, as a zero value in @offset_timer
  48 * represents disabled debouncing for the GPIO. Any other value for an element
  49 * of @offset_timer is used as an index into @timer_users. This behaviour of
  50 * the zero value aligns with the behaviour of zero built from the timer
  51 * configuration registers (i.e. debouncing is disabled).
  52 */
  53struct aspeed_gpio {
  54	struct gpio_chip chip;
  55	struct irq_chip irqc;
  56	spinlock_t lock;
  57	void __iomem *base;
  58	int irq;
  59	const struct aspeed_gpio_config *config;
  60
  61	u8 *offset_timer;
  62	unsigned int timer_users[4];
  63	struct clk *clk;
  64
  65	u32 *dcache;
  66	u8 *cf_copro_bankmap;
  67};
  68
  69struct aspeed_gpio_bank {
  70	uint16_t	val_regs;	/* +0: Rd: read input value, Wr: set write latch
  71					 * +4: Rd/Wr: Direction (0=in, 1=out)
  72					 */
  73	uint16_t	rdata_reg;	/*     Rd: read write latch, Wr: <none>  */
  74	uint16_t	irq_regs;
  75	uint16_t	debounce_regs;
  76	uint16_t	tolerance_regs;
  77	uint16_t	cmdsrc_regs;
  78	const char	names[4][3];
  79};
  80
  81/*
  82 * Note: The "value" register returns the input value sampled on the
  83 *       line even when the GPIO is configured as an output. Since
  84 *       that input goes through synchronizers, writing, then reading
  85 *       back may not return the written value right away.
  86 *
  87 *       The "rdata" register returns the content of the write latch
  88 *       and thus can be used to read back what was last written
  89 *       reliably.
  90 */
  91
  92static const int debounce_timers[4] = { 0x00, 0x50, 0x54, 0x58 };
  93
  94static const struct aspeed_gpio_copro_ops *copro_ops;
  95static void *copro_data;
  96
  97static const struct aspeed_gpio_bank aspeed_gpio_banks[] = {
  98	{
  99		.val_regs = 0x0000,
 100		.rdata_reg = 0x00c0,
 101		.irq_regs = 0x0008,
 102		.debounce_regs = 0x0040,
 103		.tolerance_regs = 0x001c,
 104		.cmdsrc_regs = 0x0060,
 105		.names = { "A", "B", "C", "D" },
 106	},
 107	{
 108		.val_regs = 0x0020,
 109		.rdata_reg = 0x00c4,
 110		.irq_regs = 0x0028,
 111		.debounce_regs = 0x0048,
 112		.tolerance_regs = 0x003c,
 113		.cmdsrc_regs = 0x0068,
 114		.names = { "E", "F", "G", "H" },
 115	},
 116	{
 117		.val_regs = 0x0070,
 118		.rdata_reg = 0x00c8,
 119		.irq_regs = 0x0098,
 120		.debounce_regs = 0x00b0,
 121		.tolerance_regs = 0x00ac,
 122		.cmdsrc_regs = 0x0090,
 123		.names = { "I", "J", "K", "L" },
 124	},
 125	{
 126		.val_regs = 0x0078,
 127		.rdata_reg = 0x00cc,
 128		.irq_regs = 0x00e8,
 129		.debounce_regs = 0x0100,
 130		.tolerance_regs = 0x00fc,
 131		.cmdsrc_regs = 0x00e0,
 132		.names = { "M", "N", "O", "P" },
 133	},
 134	{
 135		.val_regs = 0x0080,
 136		.rdata_reg = 0x00d0,
 137		.irq_regs = 0x0118,
 138		.debounce_regs = 0x0130,
 139		.tolerance_regs = 0x012c,
 140		.cmdsrc_regs = 0x0110,
 141		.names = { "Q", "R", "S", "T" },
 142	},
 143	{
 144		.val_regs = 0x0088,
 145		.rdata_reg = 0x00d4,
 146		.irq_regs = 0x0148,
 147		.debounce_regs = 0x0160,
 148		.tolerance_regs = 0x015c,
 149		.cmdsrc_regs = 0x0140,
 150		.names = { "U", "V", "W", "X" },
 151	},
 152	{
 153		.val_regs = 0x01E0,
 154		.rdata_reg = 0x00d8,
 155		.irq_regs = 0x0178,
 156		.debounce_regs = 0x0190,
 157		.tolerance_regs = 0x018c,
 158		.cmdsrc_regs = 0x0170,
 159		.names = { "Y", "Z", "AA", "AB" },
 160	},
 161	{
 162		.val_regs = 0x01e8,
 163		.rdata_reg = 0x00dc,
 164		.irq_regs = 0x01a8,
 165		.debounce_regs = 0x01c0,
 166		.tolerance_regs = 0x01bc,
 167		.cmdsrc_regs = 0x01a0,
 168		.names = { "AC", "", "", "" },
 169	},
 170};
 171
 172enum aspeed_gpio_reg {
 173	reg_val,
 174	reg_rdata,
 175	reg_dir,
 176	reg_irq_enable,
 177	reg_irq_type0,
 178	reg_irq_type1,
 179	reg_irq_type2,
 180	reg_irq_status,
 181	reg_debounce_sel1,
 182	reg_debounce_sel2,
 183	reg_tolerance,
 184	reg_cmdsrc0,
 185	reg_cmdsrc1,
 186};
 187
 188#define GPIO_VAL_VALUE	0x00
 189#define GPIO_VAL_DIR	0x04
 190
 191#define GPIO_IRQ_ENABLE	0x00
 192#define GPIO_IRQ_TYPE0	0x04
 193#define GPIO_IRQ_TYPE1	0x08
 194#define GPIO_IRQ_TYPE2	0x0c
 195#define GPIO_IRQ_STATUS	0x10
 196
 197#define GPIO_DEBOUNCE_SEL1 0x00
 198#define GPIO_DEBOUNCE_SEL2 0x04
 199
 200#define GPIO_CMDSRC_0	0x00
 201#define GPIO_CMDSRC_1	0x04
 202#define  GPIO_CMDSRC_ARM		0
 203#define  GPIO_CMDSRC_LPC		1
 204#define  GPIO_CMDSRC_COLDFIRE		2
 205#define  GPIO_CMDSRC_RESERVED		3
 206
 207/* This will be resolved at compile time */
 208static inline void __iomem *bank_reg(struct aspeed_gpio *gpio,
 209				     const struct aspeed_gpio_bank *bank,
 210				     const enum aspeed_gpio_reg reg)
 211{
 212	switch (reg) {
 213	case reg_val:
 214		return gpio->base + bank->val_regs + GPIO_VAL_VALUE;
 215	case reg_rdata:
 216		return gpio->base + bank->rdata_reg;
 217	case reg_dir:
 218		return gpio->base + bank->val_regs + GPIO_VAL_DIR;
 219	case reg_irq_enable:
 220		return gpio->base + bank->irq_regs + GPIO_IRQ_ENABLE;
 221	case reg_irq_type0:
 222		return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE0;
 223	case reg_irq_type1:
 224		return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE1;
 225	case reg_irq_type2:
 226		return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE2;
 227	case reg_irq_status:
 228		return gpio->base + bank->irq_regs + GPIO_IRQ_STATUS;
 229	case reg_debounce_sel1:
 230		return gpio->base + bank->debounce_regs + GPIO_DEBOUNCE_SEL1;
 231	case reg_debounce_sel2:
 232		return gpio->base + bank->debounce_regs + GPIO_DEBOUNCE_SEL2;
 233	case reg_tolerance:
 234		return gpio->base + bank->tolerance_regs;
 235	case reg_cmdsrc0:
 236		return gpio->base + bank->cmdsrc_regs + GPIO_CMDSRC_0;
 237	case reg_cmdsrc1:
 238		return gpio->base + bank->cmdsrc_regs + GPIO_CMDSRC_1;
 239	}
 240	BUG();
 241}
 242
 243#define GPIO_BANK(x)	((x) >> 5)
 244#define GPIO_OFFSET(x)	((x) & 0x1f)
 245#define GPIO_BIT(x)	BIT(GPIO_OFFSET(x))
 246
 247#define _GPIO_SET_DEBOUNCE(t, o, i) ((!!((t) & BIT(i))) << GPIO_OFFSET(o))
 248#define GPIO_SET_DEBOUNCE1(t, o) _GPIO_SET_DEBOUNCE(t, o, 1)
 249#define GPIO_SET_DEBOUNCE2(t, o) _GPIO_SET_DEBOUNCE(t, o, 0)
 250
 251static const struct aspeed_gpio_bank *to_bank(unsigned int offset)
 252{
 253	unsigned int bank = GPIO_BANK(offset);
 254
 255	WARN_ON(bank >= ARRAY_SIZE(aspeed_gpio_banks));
 256	return &aspeed_gpio_banks[bank];
 257}
 258
 259static inline bool is_bank_props_sentinel(const struct aspeed_bank_props *props)
 260{
 261	return !(props->input || props->output);
 262}
 263
 264static inline const struct aspeed_bank_props *find_bank_props(
 265		struct aspeed_gpio *gpio, unsigned int offset)
 266{
 267	const struct aspeed_bank_props *props = gpio->config->props;
 268
 269	while (!is_bank_props_sentinel(props)) {
 270		if (props->bank == GPIO_BANK(offset))
 271			return props;
 272		props++;
 273	}
 274
 275	return NULL;
 276}
 277
 278static inline bool have_gpio(struct aspeed_gpio *gpio, unsigned int offset)
 279{
 280	const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
 281	const struct aspeed_gpio_bank *bank = to_bank(offset);
 282	unsigned int group = GPIO_OFFSET(offset) / 8;
 283
 284	return bank->names[group][0] != '\0' &&
 285		(!props || ((props->input | props->output) & GPIO_BIT(offset)));
 286}
 287
 288static inline bool have_input(struct aspeed_gpio *gpio, unsigned int offset)
 289{
 290	const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
 291
 292	return !props || (props->input & GPIO_BIT(offset));
 293}
 294
 295#define have_irq(g, o) have_input((g), (o))
 296#define have_debounce(g, o) have_input((g), (o))
 297
 298static inline bool have_output(struct aspeed_gpio *gpio, unsigned int offset)
 299{
 300	const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
 301
 302	return !props || (props->output & GPIO_BIT(offset));
 303}
 304
 305static void aspeed_gpio_change_cmd_source(struct aspeed_gpio *gpio,
 306					  const struct aspeed_gpio_bank *bank,
 307					  int bindex, int cmdsrc)
 308{
 309	void __iomem *c0 = bank_reg(gpio, bank, reg_cmdsrc0);
 310	void __iomem *c1 = bank_reg(gpio, bank, reg_cmdsrc1);
 311	u32 bit, reg;
 312
 313	/*
 314	 * Each register controls 4 banks, so take the bottom 2
 315	 * bits of the bank index, and use them to select the
 316	 * right control bit (0, 8, 16 or 24).
 317	 */
 318	bit = BIT((bindex & 3) << 3);
 319
 320	/* Source 1 first to avoid illegal 11 combination */
 321	reg = ioread32(c1);
 322	if (cmdsrc & 2)
 323		reg |= bit;
 324	else
 325		reg &= ~bit;
 326	iowrite32(reg, c1);
 327
 328	/* Then Source 0 */
 329	reg = ioread32(c0);
 330	if (cmdsrc & 1)
 331		reg |= bit;
 332	else
 333		reg &= ~bit;
 334	iowrite32(reg, c0);
 335}
 336
 337static bool aspeed_gpio_copro_request(struct aspeed_gpio *gpio,
 338				      unsigned int offset)
 339{
 340	const struct aspeed_gpio_bank *bank = to_bank(offset);
 341
 342	if (!copro_ops || !gpio->cf_copro_bankmap)
 343		return false;
 344	if (!gpio->cf_copro_bankmap[offset >> 3])
 345		return false;
 346	if (!copro_ops->request_access)
 347		return false;
 348
 349	/* Pause the coprocessor */
 350	copro_ops->request_access(copro_data);
 351
 352	/* Change command source back to ARM */
 353	aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3, GPIO_CMDSRC_ARM);
 354
 355	/* Update cache */
 356	gpio->dcache[GPIO_BANK(offset)] = ioread32(bank_reg(gpio, bank, reg_rdata));
 357
 358	return true;
 359}
 360
 361static void aspeed_gpio_copro_release(struct aspeed_gpio *gpio,
 362				      unsigned int offset)
 363{
 364	const struct aspeed_gpio_bank *bank = to_bank(offset);
 365
 366	if (!copro_ops || !gpio->cf_copro_bankmap)
 367		return;
 368	if (!gpio->cf_copro_bankmap[offset >> 3])
 369		return;
 370	if (!copro_ops->release_access)
 371		return;
 372
 373	/* Change command source back to ColdFire */
 374	aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3,
 375				      GPIO_CMDSRC_COLDFIRE);
 376
 377	/* Restart the coprocessor */
 378	copro_ops->release_access(copro_data);
 379}
 380
 381static int aspeed_gpio_get(struct gpio_chip *gc, unsigned int offset)
 382{
 383	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
 384	const struct aspeed_gpio_bank *bank = to_bank(offset);
 385
 386	return !!(ioread32(bank_reg(gpio, bank, reg_val)) & GPIO_BIT(offset));
 387}
 388
 389static void __aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
 390			      int val)
 391{
 392	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
 393	const struct aspeed_gpio_bank *bank = to_bank(offset);
 394	void __iomem *addr;
 395	u32 reg;
 396
 397	addr = bank_reg(gpio, bank, reg_val);
 398	reg = gpio->dcache[GPIO_BANK(offset)];
 399
 400	if (val)
 401		reg |= GPIO_BIT(offset);
 402	else
 403		reg &= ~GPIO_BIT(offset);
 404	gpio->dcache[GPIO_BANK(offset)] = reg;
 405
 406	iowrite32(reg, addr);
 407}
 408
 409static void aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
 410			    int val)
 411{
 412	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
 413	unsigned long flags;
 414	bool copro;
 415
 416	spin_lock_irqsave(&gpio->lock, flags);
 417	copro = aspeed_gpio_copro_request(gpio, offset);
 418
 419	__aspeed_gpio_set(gc, offset, val);
 420
 421	if (copro)
 422		aspeed_gpio_copro_release(gpio, offset);
 423	spin_unlock_irqrestore(&gpio->lock, flags);
 424}
 425
 426static int aspeed_gpio_dir_in(struct gpio_chip *gc, unsigned int offset)
 427{
 428	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
 429	const struct aspeed_gpio_bank *bank = to_bank(offset);
 430	void __iomem *addr = bank_reg(gpio, bank, reg_dir);
 431	unsigned long flags;
 432	bool copro;
 433	u32 reg;
 434
 435	if (!have_input(gpio, offset))
 436		return -ENOTSUPP;
 437
 438	spin_lock_irqsave(&gpio->lock, flags);
 439
 440	reg = ioread32(addr);
 441	reg &= ~GPIO_BIT(offset);
 442
 443	copro = aspeed_gpio_copro_request(gpio, offset);
 444	iowrite32(reg, addr);
 445	if (copro)
 446		aspeed_gpio_copro_release(gpio, offset);
 447
 448	spin_unlock_irqrestore(&gpio->lock, flags);
 449
 450	return 0;
 451}
 452
 453static int aspeed_gpio_dir_out(struct gpio_chip *gc,
 454			       unsigned int offset, int val)
 455{
 456	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
 457	const struct aspeed_gpio_bank *bank = to_bank(offset);
 458	void __iomem *addr = bank_reg(gpio, bank, reg_dir);
 459	unsigned long flags;
 460	bool copro;
 461	u32 reg;
 462
 463	if (!have_output(gpio, offset))
 464		return -ENOTSUPP;
 465
 466	spin_lock_irqsave(&gpio->lock, flags);
 467
 468	reg = ioread32(addr);
 469	reg |= GPIO_BIT(offset);
 470
 471	copro = aspeed_gpio_copro_request(gpio, offset);
 472	__aspeed_gpio_set(gc, offset, val);
 473	iowrite32(reg, addr);
 474
 475	if (copro)
 476		aspeed_gpio_copro_release(gpio, offset);
 477	spin_unlock_irqrestore(&gpio->lock, flags);
 478
 479	return 0;
 480}
 481
 482static int aspeed_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
 483{
 484	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
 485	const struct aspeed_gpio_bank *bank = to_bank(offset);
 486	unsigned long flags;
 487	u32 val;
 488
 489	if (!have_input(gpio, offset))
 490		return GPIO_LINE_DIRECTION_OUT;
 491
 492	if (!have_output(gpio, offset))
 493		return GPIO_LINE_DIRECTION_IN;
 494
 495	spin_lock_irqsave(&gpio->lock, flags);
 496
 497	val = ioread32(bank_reg(gpio, bank, reg_dir)) & GPIO_BIT(offset);
 498
 499	spin_unlock_irqrestore(&gpio->lock, flags);
 500
 501	return val ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
 502}
 503
 504static inline int irqd_to_aspeed_gpio_data(struct irq_data *d,
 505					   struct aspeed_gpio **gpio,
 506					   const struct aspeed_gpio_bank **bank,
 507					   u32 *bit, int *offset)
 508{
 509	struct aspeed_gpio *internal;
 510
 511	*offset = irqd_to_hwirq(d);
 512
 513	internal = irq_data_get_irq_chip_data(d);
 514
 515	/* This might be a bit of a questionable place to check */
 516	if (!have_irq(internal, *offset))
 517		return -ENOTSUPP;
 518
 519	*gpio = internal;
 520	*bank = to_bank(*offset);
 521	*bit = GPIO_BIT(*offset);
 522
 523	return 0;
 524}
 525
 526static void aspeed_gpio_irq_ack(struct irq_data *d)
 527{
 528	const struct aspeed_gpio_bank *bank;
 529	struct aspeed_gpio *gpio;
 530	unsigned long flags;
 531	void __iomem *status_addr;
 532	int rc, offset;
 533	bool copro;
 534	u32 bit;
 535
 536	rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
 537	if (rc)
 538		return;
 539
 540	status_addr = bank_reg(gpio, bank, reg_irq_status);
 541
 542	spin_lock_irqsave(&gpio->lock, flags);
 543	copro = aspeed_gpio_copro_request(gpio, offset);
 544
 545	iowrite32(bit, status_addr);
 546
 547	if (copro)
 548		aspeed_gpio_copro_release(gpio, offset);
 549	spin_unlock_irqrestore(&gpio->lock, flags);
 550}
 551
 552static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set)
 553{
 554	const struct aspeed_gpio_bank *bank;
 555	struct aspeed_gpio *gpio;
 556	unsigned long flags;
 557	u32 reg, bit;
 558	void __iomem *addr;
 559	int rc, offset;
 560	bool copro;
 561
 562	rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
 563	if (rc)
 564		return;
 565
 566	addr = bank_reg(gpio, bank, reg_irq_enable);
 567
 568	spin_lock_irqsave(&gpio->lock, flags);
 569	copro = aspeed_gpio_copro_request(gpio, offset);
 570
 571	reg = ioread32(addr);
 572	if (set)
 573		reg |= bit;
 574	else
 575		reg &= ~bit;
 576	iowrite32(reg, addr);
 577
 578	if (copro)
 579		aspeed_gpio_copro_release(gpio, offset);
 580	spin_unlock_irqrestore(&gpio->lock, flags);
 581}
 582
 583static void aspeed_gpio_irq_mask(struct irq_data *d)
 584{
 585	aspeed_gpio_irq_set_mask(d, false);
 586}
 587
 588static void aspeed_gpio_irq_unmask(struct irq_data *d)
 589{
 590	aspeed_gpio_irq_set_mask(d, true);
 591}
 592
 593static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type)
 594{
 595	u32 type0 = 0;
 596	u32 type1 = 0;
 597	u32 type2 = 0;
 598	u32 bit, reg;
 599	const struct aspeed_gpio_bank *bank;
 600	irq_flow_handler_t handler;
 601	struct aspeed_gpio *gpio;
 602	unsigned long flags;
 603	void __iomem *addr;
 604	int rc, offset;
 605	bool copro;
 606
 607	rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
 608	if (rc)
 609		return -EINVAL;
 610
 611	switch (type & IRQ_TYPE_SENSE_MASK) {
 612	case IRQ_TYPE_EDGE_BOTH:
 613		type2 |= bit;
 614		fallthrough;
 615	case IRQ_TYPE_EDGE_RISING:
 616		type0 |= bit;
 617		fallthrough;
 618	case IRQ_TYPE_EDGE_FALLING:
 619		handler = handle_edge_irq;
 620		break;
 621	case IRQ_TYPE_LEVEL_HIGH:
 622		type0 |= bit;
 623		fallthrough;
 624	case IRQ_TYPE_LEVEL_LOW:
 625		type1 |= bit;
 626		handler = handle_level_irq;
 627		break;
 628	default:
 629		return -EINVAL;
 630	}
 631
 632	spin_lock_irqsave(&gpio->lock, flags);
 633	copro = aspeed_gpio_copro_request(gpio, offset);
 634
 635	addr = bank_reg(gpio, bank, reg_irq_type0);
 636	reg = ioread32(addr);
 637	reg = (reg & ~bit) | type0;
 638	iowrite32(reg, addr);
 639
 640	addr = bank_reg(gpio, bank, reg_irq_type1);
 641	reg = ioread32(addr);
 642	reg = (reg & ~bit) | type1;
 643	iowrite32(reg, addr);
 644
 645	addr = bank_reg(gpio, bank, reg_irq_type2);
 646	reg = ioread32(addr);
 647	reg = (reg & ~bit) | type2;
 648	iowrite32(reg, addr);
 649
 650	if (copro)
 651		aspeed_gpio_copro_release(gpio, offset);
 652	spin_unlock_irqrestore(&gpio->lock, flags);
 653
 654	irq_set_handler_locked(d, handler);
 655
 656	return 0;
 657}
 658
 659static void aspeed_gpio_irq_handler(struct irq_desc *desc)
 660{
 661	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
 662	struct irq_chip *ic = irq_desc_get_chip(desc);
 663	struct aspeed_gpio *data = gpiochip_get_data(gc);
 664	unsigned int i, p, girq, banks;
 665	unsigned long reg;
 666	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
 667
 668	chained_irq_enter(ic, desc);
 669
 670	banks = DIV_ROUND_UP(gpio->chip.ngpio, 32);
 671	for (i = 0; i < banks; i++) {
 672		const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
 673
 674		reg = ioread32(bank_reg(data, bank, reg_irq_status));
 675
 676		for_each_set_bit(p, &reg, 32) {
 677			girq = irq_find_mapping(gc->irq.domain, i * 32 + p);
 678			generic_handle_irq(girq);
 679		}
 680
 681	}
 682
 683	chained_irq_exit(ic, desc);
 684}
 685
 686static void aspeed_init_irq_valid_mask(struct gpio_chip *gc,
 687				       unsigned long *valid_mask,
 688				       unsigned int ngpios)
 689{
 690	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
 691	const struct aspeed_bank_props *props = gpio->config->props;
 692
 693	while (!is_bank_props_sentinel(props)) {
 694		unsigned int offset;
 695		const unsigned long int input = props->input;
 696
 697		/* Pretty crummy approach, but similar to GPIO core */
 698		for_each_clear_bit(offset, &input, 32) {
 699			unsigned int i = props->bank * 32 + offset;
 700
 701			if (i >= gpio->chip.ngpio)
 702				break;
 703
 704			clear_bit(i, valid_mask);
 705		}
 706
 707		props++;
 708	}
 709}
 710
 711static int aspeed_gpio_reset_tolerance(struct gpio_chip *chip,
 712					unsigned int offset, bool enable)
 713{
 714	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
 715	unsigned long flags;
 716	void __iomem *treg;
 717	bool copro;
 718	u32 val;
 719
 720	treg = bank_reg(gpio, to_bank(offset), reg_tolerance);
 721
 722	spin_lock_irqsave(&gpio->lock, flags);
 723	copro = aspeed_gpio_copro_request(gpio, offset);
 724
 725	val = readl(treg);
 726
 727	if (enable)
 728		val |= GPIO_BIT(offset);
 729	else
 730		val &= ~GPIO_BIT(offset);
 731
 732	writel(val, treg);
 733
 734	if (copro)
 735		aspeed_gpio_copro_release(gpio, offset);
 736	spin_unlock_irqrestore(&gpio->lock, flags);
 737
 738	return 0;
 739}
 740
 741static int aspeed_gpio_request(struct gpio_chip *chip, unsigned int offset)
 742{
 743	if (!have_gpio(gpiochip_get_data(chip), offset))
 744		return -ENODEV;
 745
 746	return pinctrl_gpio_request(chip->base + offset);
 747}
 748
 749static void aspeed_gpio_free(struct gpio_chip *chip, unsigned int offset)
 750{
 751	pinctrl_gpio_free(chip->base + offset);
 752}
 753
 754static int usecs_to_cycles(struct aspeed_gpio *gpio, unsigned long usecs,
 755		u32 *cycles)
 756{
 757	u64 rate;
 758	u64 n;
 759	u32 r;
 760
 761	rate = clk_get_rate(gpio->clk);
 762	if (!rate)
 763		return -ENOTSUPP;
 764
 765	n = rate * usecs;
 766	r = do_div(n, 1000000);
 767
 768	if (n >= U32_MAX)
 769		return -ERANGE;
 770
 771	/* At least as long as the requested time */
 772	*cycles = n + (!!r);
 773
 774	return 0;
 775}
 776
 777/* Call under gpio->lock */
 778static int register_allocated_timer(struct aspeed_gpio *gpio,
 779		unsigned int offset, unsigned int timer)
 780{
 781	if (WARN(gpio->offset_timer[offset] != 0,
 782				"Offset %d already allocated timer %d\n",
 783				offset, gpio->offset_timer[offset]))
 784		return -EINVAL;
 785
 786	if (WARN(gpio->timer_users[timer] == UINT_MAX,
 787				"Timer user count would overflow\n"))
 788		return -EPERM;
 789
 790	gpio->offset_timer[offset] = timer;
 791	gpio->timer_users[timer]++;
 792
 793	return 0;
 794}
 795
 796/* Call under gpio->lock */
 797static int unregister_allocated_timer(struct aspeed_gpio *gpio,
 798		unsigned int offset)
 799{
 800	if (WARN(gpio->offset_timer[offset] == 0,
 801				"No timer allocated to offset %d\n", offset))
 802		return -EINVAL;
 803
 804	if (WARN(gpio->timer_users[gpio->offset_timer[offset]] == 0,
 805				"No users recorded for timer %d\n",
 806				gpio->offset_timer[offset]))
 807		return -EINVAL;
 808
 809	gpio->timer_users[gpio->offset_timer[offset]]--;
 810	gpio->offset_timer[offset] = 0;
 811
 812	return 0;
 813}
 814
 815/* Call under gpio->lock */
 816static inline bool timer_allocation_registered(struct aspeed_gpio *gpio,
 817		unsigned int offset)
 818{
 819	return gpio->offset_timer[offset] > 0;
 820}
 821
 822/* Call under gpio->lock */
 823static void configure_timer(struct aspeed_gpio *gpio, unsigned int offset,
 824		unsigned int timer)
 825{
 826	const struct aspeed_gpio_bank *bank = to_bank(offset);
 827	const u32 mask = GPIO_BIT(offset);
 828	void __iomem *addr;
 829	u32 val;
 830
 831	/* Note: Debounce timer isn't under control of the command
 832	 * source registers, so no need to sync with the coprocessor
 833	 */
 834	addr = bank_reg(gpio, bank, reg_debounce_sel1);
 835	val = ioread32(addr);
 836	iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE1(timer, offset), addr);
 837
 838	addr = bank_reg(gpio, bank, reg_debounce_sel2);
 839	val = ioread32(addr);
 840	iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE2(timer, offset), addr);
 841}
 842
 843static int enable_debounce(struct gpio_chip *chip, unsigned int offset,
 844				    unsigned long usecs)
 845{
 846	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
 847	u32 requested_cycles;
 848	unsigned long flags;
 849	int rc;
 850	int i;
 851
 852	if (!gpio->clk)
 853		return -EINVAL;
 854
 855	rc = usecs_to_cycles(gpio, usecs, &requested_cycles);
 856	if (rc < 0) {
 857		dev_warn(chip->parent, "Failed to convert %luus to cycles at %luHz: %d\n",
 858				usecs, clk_get_rate(gpio->clk), rc);
 859		return rc;
 860	}
 861
 862	spin_lock_irqsave(&gpio->lock, flags);
 863
 864	if (timer_allocation_registered(gpio, offset)) {
 865		rc = unregister_allocated_timer(gpio, offset);
 866		if (rc < 0)
 867			goto out;
 868	}
 869
 870	/* Try to find a timer already configured for the debounce period */
 871	for (i = 1; i < ARRAY_SIZE(debounce_timers); i++) {
 872		u32 cycles;
 873
 874		cycles = ioread32(gpio->base + debounce_timers[i]);
 875		if (requested_cycles == cycles)
 876			break;
 877	}
 878
 879	if (i == ARRAY_SIZE(debounce_timers)) {
 880		int j;
 881
 882		/*
 883		 * As there are no timers configured for the requested debounce
 884		 * period, find an unused timer instead
 885		 */
 886		for (j = 1; j < ARRAY_SIZE(gpio->timer_users); j++) {
 887			if (gpio->timer_users[j] == 0)
 888				break;
 889		}
 890
 891		if (j == ARRAY_SIZE(gpio->timer_users)) {
 892			dev_warn(chip->parent,
 893					"Debounce timers exhausted, cannot debounce for period %luus\n",
 894					usecs);
 895
 896			rc = -EPERM;
 897
 898			/*
 899			 * We already adjusted the accounting to remove @offset
 900			 * as a user of its previous timer, so also configure
 901			 * the hardware so @offset has timers disabled for
 902			 * consistency.
 903			 */
 904			configure_timer(gpio, offset, 0);
 905			goto out;
 906		}
 907
 908		i = j;
 909
 910		iowrite32(requested_cycles, gpio->base + debounce_timers[i]);
 911	}
 912
 913	if (WARN(i == 0, "Cannot register index of disabled timer\n")) {
 914		rc = -EINVAL;
 915		goto out;
 916	}
 917
 918	register_allocated_timer(gpio, offset, i);
 919	configure_timer(gpio, offset, i);
 920
 921out:
 922	spin_unlock_irqrestore(&gpio->lock, flags);
 923
 924	return rc;
 925}
 926
 927static int disable_debounce(struct gpio_chip *chip, unsigned int offset)
 928{
 929	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
 930	unsigned long flags;
 931	int rc;
 932
 933	spin_lock_irqsave(&gpio->lock, flags);
 934
 935	rc = unregister_allocated_timer(gpio, offset);
 936	if (!rc)
 937		configure_timer(gpio, offset, 0);
 938
 939	spin_unlock_irqrestore(&gpio->lock, flags);
 940
 941	return rc;
 942}
 943
 944static int set_debounce(struct gpio_chip *chip, unsigned int offset,
 945				    unsigned long usecs)
 946{
 947	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
 948
 949	if (!have_debounce(gpio, offset))
 950		return -ENOTSUPP;
 951
 952	if (usecs)
 953		return enable_debounce(chip, offset, usecs);
 954
 955	return disable_debounce(chip, offset);
 956}
 957
 958static int aspeed_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
 959				  unsigned long config)
 960{
 961	unsigned long param = pinconf_to_config_param(config);
 962	u32 arg = pinconf_to_config_argument(config);
 963
 964	if (param == PIN_CONFIG_INPUT_DEBOUNCE)
 965		return set_debounce(chip, offset, arg);
 966	else if (param == PIN_CONFIG_BIAS_DISABLE ||
 967			param == PIN_CONFIG_BIAS_PULL_DOWN ||
 968			param == PIN_CONFIG_DRIVE_STRENGTH)
 969		return pinctrl_gpio_set_config(offset, config);
 970	else if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN ||
 971			param == PIN_CONFIG_DRIVE_OPEN_SOURCE)
 972		/* Return -ENOTSUPP to trigger emulation, as per datasheet */
 973		return -ENOTSUPP;
 974	else if (param == PIN_CONFIG_PERSIST_STATE)
 975		return aspeed_gpio_reset_tolerance(chip, offset, arg);
 976
 977	return -ENOTSUPP;
 978}
 979
 980/**
 981 * aspeed_gpio_copro_set_ops - Sets the callbacks used for handshaking with
 982 *                             the coprocessor for shared GPIO banks
 983 * @ops: The callbacks
 984 * @data: Pointer passed back to the callbacks
 985 */
 986int aspeed_gpio_copro_set_ops(const struct aspeed_gpio_copro_ops *ops, void *data)
 987{
 988	copro_data = data;
 989	copro_ops = ops;
 990
 991	return 0;
 992}
 993EXPORT_SYMBOL_GPL(aspeed_gpio_copro_set_ops);
 994
 995/**
 996 * aspeed_gpio_copro_grab_gpio - Mark a GPIO used by the coprocessor. The entire
 997 *                               bank gets marked and any access from the ARM will
 998 *                               result in handshaking via callbacks.
 999 * @desc: The GPIO to be marked
1000 * @vreg_offset: If non-NULL, returns the value register offset in the GPIO space
1001 * @dreg_offset: If non-NULL, returns the data latch register offset in the GPIO space
1002 * @bit: If non-NULL, returns the bit number of the GPIO in the registers
1003 */
1004int aspeed_gpio_copro_grab_gpio(struct gpio_desc *desc,
1005				u16 *vreg_offset, u16 *dreg_offset, u8 *bit)
1006{
1007	struct gpio_chip *chip = gpiod_to_chip(desc);
1008	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
1009	int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
1010	const struct aspeed_gpio_bank *bank = to_bank(offset);
1011	unsigned long flags;
1012
1013	if (!gpio->cf_copro_bankmap)
1014		gpio->cf_copro_bankmap = kzalloc(gpio->chip.ngpio >> 3, GFP_KERNEL);
1015	if (!gpio->cf_copro_bankmap)
1016		return -ENOMEM;
1017	if (offset < 0 || offset > gpio->chip.ngpio)
1018		return -EINVAL;
1019	bindex = offset >> 3;
1020
1021	spin_lock_irqsave(&gpio->lock, flags);
1022
1023	/* Sanity check, this shouldn't happen */
1024	if (gpio->cf_copro_bankmap[bindex] == 0xff) {
1025		rc = -EIO;
1026		goto bail;
1027	}
1028	gpio->cf_copro_bankmap[bindex]++;
1029
1030	/* Switch command source */
1031	if (gpio->cf_copro_bankmap[bindex] == 1)
1032		aspeed_gpio_change_cmd_source(gpio, bank, bindex,
1033					      GPIO_CMDSRC_COLDFIRE);
1034
1035	if (vreg_offset)
1036		*vreg_offset = bank->val_regs;
1037	if (dreg_offset)
1038		*dreg_offset = bank->rdata_reg;
1039	if (bit)
1040		*bit = GPIO_OFFSET(offset);
1041 bail:
1042	spin_unlock_irqrestore(&gpio->lock, flags);
1043	return rc;
1044}
1045EXPORT_SYMBOL_GPL(aspeed_gpio_copro_grab_gpio);
1046
1047/**
1048 * aspeed_gpio_copro_release_gpio - Unmark a GPIO used by the coprocessor.
1049 * @desc: The GPIO to be marked
1050 */
1051int aspeed_gpio_copro_release_gpio(struct gpio_desc *desc)
1052{
1053	struct gpio_chip *chip = gpiod_to_chip(desc);
1054	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
1055	int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
1056	const struct aspeed_gpio_bank *bank = to_bank(offset);
1057	unsigned long flags;
1058
1059	if (!gpio->cf_copro_bankmap)
1060		return -ENXIO;
1061
1062	if (offset < 0 || offset > gpio->chip.ngpio)
1063		return -EINVAL;
1064	bindex = offset >> 3;
1065
1066	spin_lock_irqsave(&gpio->lock, flags);
1067
1068	/* Sanity check, this shouldn't happen */
1069	if (gpio->cf_copro_bankmap[bindex] == 0) {
1070		rc = -EIO;
1071		goto bail;
1072	}
1073	gpio->cf_copro_bankmap[bindex]--;
1074
1075	/* Switch command source */
1076	if (gpio->cf_copro_bankmap[bindex] == 0)
1077		aspeed_gpio_change_cmd_source(gpio, bank, bindex,
1078					      GPIO_CMDSRC_ARM);
1079 bail:
1080	spin_unlock_irqrestore(&gpio->lock, flags);
1081	return rc;
1082}
1083EXPORT_SYMBOL_GPL(aspeed_gpio_copro_release_gpio);
1084
1085/*
1086 * Any banks not specified in a struct aspeed_bank_props array are assumed to
1087 * have the properties:
1088 *
1089 *     { .input = 0xffffffff, .output = 0xffffffff }
1090 */
1091
1092static const struct aspeed_bank_props ast2400_bank_props[] = {
1093	/*     input	  output   */
1094	{ 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */
1095	{ 6, 0x0000000f, 0x0fffff0f }, /* Y/Z/AA/AB, two 4-GPIO holes */
1096	{ },
1097};
1098
1099static const struct aspeed_gpio_config ast2400_config =
1100	/* 220 for simplicity, really 216 with two 4-GPIO holes, four at end */
1101	{ .nr_gpios = 220, .props = ast2400_bank_props, };
1102
1103static const struct aspeed_bank_props ast2500_bank_props[] = {
1104	/*     input	  output   */
1105	{ 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */
1106	{ 6, 0x0fffffff, 0x0fffffff }, /* Y/Z/AA/AB, 4-GPIO hole */
1107	{ 7, 0x000000ff, 0x000000ff }, /* AC */
1108	{ },
1109};
1110
1111static const struct aspeed_gpio_config ast2500_config =
1112	/* 232 for simplicity, actual number is 228 (4-GPIO hole in GPIOAB) */
1113	{ .nr_gpios = 232, .props = ast2500_bank_props, };
1114
1115static const struct aspeed_bank_props ast2600_bank_props[] = {
1116	/*     input	  output   */
1117	{4, 0xffffffff,  0x00ffffff}, /* Q/R/S/T */
1118	{5, 0xffffffff,  0xffffff00}, /* U/V/W/X */
1119	{6, 0x0000ffff,  0x0000ffff}, /* Y/Z */
1120	{ },
1121};
1122
1123static const struct aspeed_gpio_config ast2600_config =
1124	/*
1125	 * ast2600 has two controllers one with 208 GPIOs and one with 36 GPIOs.
1126	 * We expect ngpio being set in the device tree and this is a fallback
1127	 * option.
1128	 */
1129	{ .nr_gpios = 208, .props = ast2600_bank_props, };
1130
1131static const struct of_device_id aspeed_gpio_of_table[] = {
1132	{ .compatible = "aspeed,ast2400-gpio", .data = &ast2400_config, },
1133	{ .compatible = "aspeed,ast2500-gpio", .data = &ast2500_config, },
1134	{ .compatible = "aspeed,ast2600-gpio", .data = &ast2600_config, },
1135	{}
1136};
1137MODULE_DEVICE_TABLE(of, aspeed_gpio_of_table);
1138
1139static int __init aspeed_gpio_probe(struct platform_device *pdev)
1140{
1141	const struct of_device_id *gpio_id;
1142	struct aspeed_gpio *gpio;
1143	int rc, i, banks, err;
1144	u32 ngpio;
1145
1146	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
1147	if (!gpio)
1148		return -ENOMEM;
1149
1150	gpio->base = devm_platform_ioremap_resource(pdev, 0);
1151	if (IS_ERR(gpio->base))
1152		return PTR_ERR(gpio->base);
1153
1154	spin_lock_init(&gpio->lock);
1155
1156	gpio_id = of_match_node(aspeed_gpio_of_table, pdev->dev.of_node);
1157	if (!gpio_id)
1158		return -EINVAL;
1159
1160	gpio->clk = of_clk_get(pdev->dev.of_node, 0);
1161	if (IS_ERR(gpio->clk)) {
1162		dev_warn(&pdev->dev,
1163				"Failed to get clock from devicetree, debouncing disabled\n");
1164		gpio->clk = NULL;
1165	}
1166
1167	gpio->config = gpio_id->data;
1168
1169	gpio->chip.parent = &pdev->dev;
1170	err = of_property_read_u32(pdev->dev.of_node, "ngpios", &ngpio);
1171	gpio->chip.ngpio = (u16) ngpio;
1172	if (err)
1173		gpio->chip.ngpio = gpio->config->nr_gpios;
1174	gpio->chip.direction_input = aspeed_gpio_dir_in;
1175	gpio->chip.direction_output = aspeed_gpio_dir_out;
1176	gpio->chip.get_direction = aspeed_gpio_get_direction;
1177	gpio->chip.request = aspeed_gpio_request;
1178	gpio->chip.free = aspeed_gpio_free;
1179	gpio->chip.get = aspeed_gpio_get;
1180	gpio->chip.set = aspeed_gpio_set;
1181	gpio->chip.set_config = aspeed_gpio_set_config;
1182	gpio->chip.label = dev_name(&pdev->dev);
1183	gpio->chip.base = -1;
1184
1185	/* Allocate a cache of the output registers */
1186	banks = DIV_ROUND_UP(gpio->chip.ngpio, 32);
1187	gpio->dcache = devm_kcalloc(&pdev->dev,
1188				    banks, sizeof(u32), GFP_KERNEL);
1189	if (!gpio->dcache)
1190		return -ENOMEM;
1191
1192	/*
1193	 * Populate it with initial values read from the HW and switch
1194	 * all command sources to the ARM by default
1195	 */
1196	for (i = 0; i < banks; i++) {
1197		const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
1198		void __iomem *addr = bank_reg(gpio, bank, reg_rdata);
1199		gpio->dcache[i] = ioread32(addr);
1200		aspeed_gpio_change_cmd_source(gpio, bank, 0, GPIO_CMDSRC_ARM);
1201		aspeed_gpio_change_cmd_source(gpio, bank, 1, GPIO_CMDSRC_ARM);
1202		aspeed_gpio_change_cmd_source(gpio, bank, 2, GPIO_CMDSRC_ARM);
1203		aspeed_gpio_change_cmd_source(gpio, bank, 3, GPIO_CMDSRC_ARM);
1204	}
1205
1206	/* Optionally set up an irqchip if there is an IRQ */
1207	rc = platform_get_irq(pdev, 0);
1208	if (rc > 0) {
1209		struct gpio_irq_chip *girq;
1210
1211		gpio->irq = rc;
1212		girq = &gpio->chip.irq;
1213		girq->chip = &gpio->irqc;
1214		girq->chip->name = dev_name(&pdev->dev);
1215		girq->chip->irq_ack = aspeed_gpio_irq_ack;
1216		girq->chip->irq_mask = aspeed_gpio_irq_mask;
1217		girq->chip->irq_unmask = aspeed_gpio_irq_unmask;
1218		girq->chip->irq_set_type = aspeed_gpio_set_type;
1219		girq->parent_handler = aspeed_gpio_irq_handler;
1220		girq->num_parents = 1;
1221		girq->parents = devm_kcalloc(&pdev->dev, 1,
1222					     sizeof(*girq->parents),
1223					     GFP_KERNEL);
1224		if (!girq->parents)
1225			return -ENOMEM;
1226		girq->parents[0] = gpio->irq;
1227		girq->default_type = IRQ_TYPE_NONE;
1228		girq->handler = handle_bad_irq;
1229		girq->init_valid_mask = aspeed_init_irq_valid_mask;
1230	}
1231
1232	gpio->offset_timer =
1233		devm_kzalloc(&pdev->dev, gpio->chip.ngpio, GFP_KERNEL);
1234	if (!gpio->offset_timer)
1235		return -ENOMEM;
1236
1237	rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
1238	if (rc < 0)
1239		return rc;
1240
1241	return 0;
1242}
1243
1244static struct platform_driver aspeed_gpio_driver = {
1245	.driver = {
1246		.name = KBUILD_MODNAME,
1247		.of_match_table = aspeed_gpio_of_table,
1248	},
1249};
1250
1251module_platform_driver_probe(aspeed_gpio_driver, aspeed_gpio_probe);
1252
1253MODULE_DESCRIPTION("Aspeed GPIO Driver");
1254MODULE_LICENSE("GPL");