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v5.4
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Driver for OMAP-UART controller.
   4 * Based on drivers/serial/8250.c
   5 *
   6 * Copyright (C) 2010 Texas Instruments.
   7 *
   8 * Authors:
   9 *	Govindraj R	<govindraj.raja@ti.com>
  10 *	Thara Gopinath	<thara@ti.com>
  11 *
  12 * Note: This driver is made separate from 8250 driver as we cannot
  13 * over load 8250 driver with omap platform specific configuration for
  14 * features like DMA, it makes easier to implement features like DMA and
  15 * hardware flow control and software flow control configuration with
  16 * this driver as required for the omap-platform.
  17 */
  18
  19#if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  20#define SUPPORT_SYSRQ
  21#endif
  22
  23#include <linux/module.h>
  24#include <linux/init.h>
  25#include <linux/console.h>
  26#include <linux/serial_reg.h>
  27#include <linux/delay.h>
  28#include <linux/slab.h>
  29#include <linux/tty.h>
  30#include <linux/tty_flip.h>
  31#include <linux/platform_device.h>
  32#include <linux/io.h>
  33#include <linux/clk.h>
  34#include <linux/serial_core.h>
  35#include <linux/irq.h>
  36#include <linux/pm_runtime.h>
  37#include <linux/pm_wakeirq.h>
  38#include <linux/of.h>
  39#include <linux/of_irq.h>
  40#include <linux/gpio.h>
  41#include <linux/of_gpio.h>
  42#include <linux/platform_data/serial-omap.h>
  43
  44#include <dt-bindings/gpio/gpio.h>
  45
  46#define OMAP_MAX_HSUART_PORTS	10
  47
  48#define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
  49
  50#define OMAP_UART_REV_42 0x0402
  51#define OMAP_UART_REV_46 0x0406
  52#define OMAP_UART_REV_52 0x0502
  53#define OMAP_UART_REV_63 0x0603
  54
  55#define OMAP_UART_TX_WAKEUP_EN		BIT(7)
  56
  57/* Feature flags */
  58#define OMAP_UART_WER_HAS_TX_WAKEUP	BIT(0)
  59
  60#define UART_ERRATA_i202_MDR1_ACCESS	BIT(0)
  61#define UART_ERRATA_i291_DMA_FORCEIDLE	BIT(1)
  62
  63#define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
  64
  65/* SCR register bitmasks */
  66#define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK		(1 << 7)
  67#define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK		(1 << 6)
  68#define OMAP_UART_SCR_TX_EMPTY			(1 << 3)
  69
  70/* FCR register bitmasks */
  71#define OMAP_UART_FCR_RX_FIFO_TRIG_MASK			(0x3 << 6)
  72#define OMAP_UART_FCR_TX_FIFO_TRIG_MASK			(0x3 << 4)
  73
  74/* MVR register bitmasks */
  75#define OMAP_UART_MVR_SCHEME_SHIFT	30
  76
  77#define OMAP_UART_LEGACY_MVR_MAJ_MASK	0xf0
  78#define OMAP_UART_LEGACY_MVR_MAJ_SHIFT	4
  79#define OMAP_UART_LEGACY_MVR_MIN_MASK	0x0f
  80
  81#define OMAP_UART_MVR_MAJ_MASK		0x700
  82#define OMAP_UART_MVR_MAJ_SHIFT		8
  83#define OMAP_UART_MVR_MIN_MASK		0x3f
  84
  85#define OMAP_UART_DMA_CH_FREE	-1
  86
  87#define MSR_SAVE_FLAGS		UART_MSR_ANY_DELTA
  88#define OMAP_MODE13X_SPEED	230400
  89
  90/* WER = 0x7F
  91 * Enable module level wakeup in WER reg
  92 */
  93#define OMAP_UART_WER_MOD_WKUP	0x7F
  94
  95/* Enable XON/XOFF flow control on output */
  96#define OMAP_UART_SW_TX		0x08
  97
  98/* Enable XON/XOFF flow control on input */
  99#define OMAP_UART_SW_RX		0x02
 100
 101#define OMAP_UART_SW_CLR	0xF0
 102
 103#define OMAP_UART_TCR_TRIG	0x0F
 104
 105struct uart_omap_dma {
 106	u8			uart_dma_tx;
 107	u8			uart_dma_rx;
 108	int			rx_dma_channel;
 109	int			tx_dma_channel;
 110	dma_addr_t		rx_buf_dma_phys;
 111	dma_addr_t		tx_buf_dma_phys;
 112	unsigned int		uart_base;
 113	/*
 114	 * Buffer for rx dma. It is not required for tx because the buffer
 115	 * comes from port structure.
 116	 */
 117	unsigned char		*rx_buf;
 118	unsigned int		prev_rx_dma_pos;
 119	int			tx_buf_size;
 120	int			tx_dma_used;
 121	int			rx_dma_used;
 122	spinlock_t		tx_lock;
 123	spinlock_t		rx_lock;
 124	/* timer to poll activity on rx dma */
 125	struct timer_list	rx_timer;
 126	unsigned int		rx_buf_size;
 127	unsigned int		rx_poll_rate;
 128	unsigned int		rx_timeout;
 129};
 130
 131struct uart_omap_port {
 132	struct uart_port	port;
 133	struct uart_omap_dma	uart_dma;
 134	struct device		*dev;
 135	int			wakeirq;
 136
 137	unsigned char		ier;
 138	unsigned char		lcr;
 139	unsigned char		mcr;
 140	unsigned char		fcr;
 141	unsigned char		efr;
 142	unsigned char		dll;
 143	unsigned char		dlh;
 144	unsigned char		mdr1;
 145	unsigned char		scr;
 146	unsigned char		wer;
 147
 148	int			use_dma;
 149	/*
 150	 * Some bits in registers are cleared on a read, so they must
 151	 * be saved whenever the register is read, but the bits will not
 152	 * be immediately processed.
 153	 */
 154	unsigned int		lsr_break_flag;
 155	unsigned char		msr_saved_flags;
 156	char			name[20];
 157	unsigned long		port_activity;
 158	int			context_loss_cnt;
 159	u32			errata;
 160	u32			features;
 161
 162	int			rts_gpio;
 163
 164	struct pm_qos_request	pm_qos_request;
 165	u32			latency;
 166	u32			calc_latency;
 167	struct work_struct	qos_work;
 168	bool			is_suspending;
 169};
 170
 171#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
 172
 173static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
 174
 175/* Forward declaration of functions */
 176static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
 177
 178static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
 179{
 180	offset <<= up->port.regshift;
 181	return readw(up->port.membase + offset);
 182}
 183
 184static inline void serial_out(struct uart_omap_port *up, int offset, int value)
 185{
 186	offset <<= up->port.regshift;
 187	writew(value, up->port.membase + offset);
 188}
 189
 190static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
 191{
 192	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
 193	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
 194		       UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
 195	serial_out(up, UART_FCR, 0);
 196}
 197
 198#ifdef CONFIG_PM
 199static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
 200{
 201	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
 202
 203	if (!pdata || !pdata->get_context_loss_count)
 204		return -EINVAL;
 205
 206	return pdata->get_context_loss_count(up->dev);
 207}
 208
 209/* REVISIT: Remove this when omap3 boots in device tree only mode */
 210static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
 211{
 212	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
 213
 214	if (!pdata || !pdata->enable_wakeup)
 215		return;
 216
 217	pdata->enable_wakeup(up->dev, enable);
 218}
 219#endif /* CONFIG_PM */
 220
 221/*
 222 * Calculate the absolute difference between the desired and actual baud
 223 * rate for the given mode.
 224 */
 225static inline int calculate_baud_abs_diff(struct uart_port *port,
 226				unsigned int baud, unsigned int mode)
 227{
 228	unsigned int n = port->uartclk / (mode * baud);
 229	int abs_diff;
 230
 231	if (n == 0)
 232		n = 1;
 233
 234	abs_diff = baud - (port->uartclk / (mode * n));
 235	if (abs_diff < 0)
 236		abs_diff = -abs_diff;
 237
 238	return abs_diff;
 239}
 240
 241/*
 242 * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
 243 * @port: uart port info
 244 * @baud: baudrate for which mode needs to be determined
 245 *
 246 * Returns true if baud rate is MODE16X and false if MODE13X
 247 * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
 248 * and Error Rates" determines modes not for all common baud rates.
 249 * E.g. for 1000000 baud rate mode must be 16x, but according to that
 250 * table it's determined as 13x.
 251 */
 252static bool
 253serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
 254{
 255	int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
 256	int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
 257
 258	return (abs_diff_13 >= abs_diff_16);
 259}
 260
 261/*
 262 * serial_omap_get_divisor - calculate divisor value
 263 * @port: uart port info
 264 * @baud: baudrate for which divisor needs to be calculated.
 265 */
 266static unsigned int
 267serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
 268{
 269	unsigned int mode;
 270
 271	if (!serial_omap_baud_is_mode16(port, baud))
 272		mode = 13;
 273	else
 274		mode = 16;
 275	return port->uartclk/(mode * baud);
 276}
 277
 278static void serial_omap_enable_ms(struct uart_port *port)
 279{
 280	struct uart_omap_port *up = to_uart_omap_port(port);
 281
 282	dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
 283
 284	pm_runtime_get_sync(up->dev);
 285	up->ier |= UART_IER_MSI;
 286	serial_out(up, UART_IER, up->ier);
 287	pm_runtime_mark_last_busy(up->dev);
 288	pm_runtime_put_autosuspend(up->dev);
 289}
 290
 291static void serial_omap_stop_tx(struct uart_port *port)
 292{
 293	struct uart_omap_port *up = to_uart_omap_port(port);
 294	int res;
 295
 296	pm_runtime_get_sync(up->dev);
 297
 298	/* Handle RS-485 */
 299	if (port->rs485.flags & SER_RS485_ENABLED) {
 300		if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
 301			/* THR interrupt is fired when both TX FIFO and TX
 302			 * shift register are empty. This means there's nothing
 303			 * left to transmit now, so make sure the THR interrupt
 304			 * is fired when TX FIFO is below the trigger level,
 305			 * disable THR interrupts and toggle the RS-485 GPIO
 306			 * data direction pin if needed.
 307			 */
 308			up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
 309			serial_out(up, UART_OMAP_SCR, up->scr);
 310			res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
 311				1 : 0;
 312			if (gpio_get_value(up->rts_gpio) != res) {
 313				if (port->rs485.delay_rts_after_send > 0)
 314					mdelay(
 315					port->rs485.delay_rts_after_send);
 316				gpio_set_value(up->rts_gpio, res);
 317			}
 318		} else {
 319			/* We're asked to stop, but there's still stuff in the
 320			 * UART FIFO, so make sure the THR interrupt is fired
 321			 * when both TX FIFO and TX shift register are empty.
 322			 * The next THR interrupt (if no transmission is started
 323			 * in the meantime) will indicate the end of a
 324			 * transmission. Therefore we _don't_ disable THR
 325			 * interrupts in this situation.
 326			 */
 327			up->scr |= OMAP_UART_SCR_TX_EMPTY;
 328			serial_out(up, UART_OMAP_SCR, up->scr);
 329			return;
 330		}
 331	}
 332
 333	if (up->ier & UART_IER_THRI) {
 334		up->ier &= ~UART_IER_THRI;
 335		serial_out(up, UART_IER, up->ier);
 336	}
 337
 338	if ((port->rs485.flags & SER_RS485_ENABLED) &&
 339	    !(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
 340		/*
 341		 * Empty the RX FIFO, we are not interested in anything
 342		 * received during the half-duplex transmission.
 343		 */
 344		serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_RCVR);
 345		/* Re-enable RX interrupts */
 346		up->ier |= UART_IER_RLSI | UART_IER_RDI;
 347		up->port.read_status_mask |= UART_LSR_DR;
 348		serial_out(up, UART_IER, up->ier);
 349	}
 350
 351	pm_runtime_mark_last_busy(up->dev);
 352	pm_runtime_put_autosuspend(up->dev);
 353}
 354
 355static void serial_omap_stop_rx(struct uart_port *port)
 356{
 357	struct uart_omap_port *up = to_uart_omap_port(port);
 358
 359	pm_runtime_get_sync(up->dev);
 360	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
 361	up->port.read_status_mask &= ~UART_LSR_DR;
 362	serial_out(up, UART_IER, up->ier);
 363	pm_runtime_mark_last_busy(up->dev);
 364	pm_runtime_put_autosuspend(up->dev);
 365}
 366
 367static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
 368{
 369	struct circ_buf *xmit = &up->port.state->xmit;
 370	int count;
 371
 372	if (up->port.x_char) {
 373		serial_out(up, UART_TX, up->port.x_char);
 374		up->port.icount.tx++;
 375		up->port.x_char = 0;
 376		return;
 377	}
 378	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 379		serial_omap_stop_tx(&up->port);
 380		return;
 381	}
 382	count = up->port.fifosize / 4;
 383	do {
 384		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
 385		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 386		up->port.icount.tx++;
 387		if (uart_circ_empty(xmit))
 388			break;
 389	} while (--count > 0);
 390
 391	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 392		uart_write_wakeup(&up->port);
 393
 394	if (uart_circ_empty(xmit))
 395		serial_omap_stop_tx(&up->port);
 396}
 397
 398static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
 399{
 400	if (!(up->ier & UART_IER_THRI)) {
 401		up->ier |= UART_IER_THRI;
 402		serial_out(up, UART_IER, up->ier);
 403	}
 404}
 405
 406static void serial_omap_start_tx(struct uart_port *port)
 407{
 408	struct uart_omap_port *up = to_uart_omap_port(port);
 409	int res;
 410
 411	pm_runtime_get_sync(up->dev);
 412
 413	/* Handle RS-485 */
 414	if (port->rs485.flags & SER_RS485_ENABLED) {
 415		/* Fire THR interrupts when FIFO is below trigger level */
 416		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
 417		serial_out(up, UART_OMAP_SCR, up->scr);
 418
 419		/* if rts not already enabled */
 420		res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
 421		if (gpio_get_value(up->rts_gpio) != res) {
 422			gpio_set_value(up->rts_gpio, res);
 423			if (port->rs485.delay_rts_before_send > 0)
 424				mdelay(port->rs485.delay_rts_before_send);
 425		}
 426	}
 427
 428	if ((port->rs485.flags & SER_RS485_ENABLED) &&
 429	    !(port->rs485.flags & SER_RS485_RX_DURING_TX))
 430		serial_omap_stop_rx(port);
 431
 432	serial_omap_enable_ier_thri(up);
 433	pm_runtime_mark_last_busy(up->dev);
 434	pm_runtime_put_autosuspend(up->dev);
 435}
 436
 437static void serial_omap_throttle(struct uart_port *port)
 438{
 439	struct uart_omap_port *up = to_uart_omap_port(port);
 440	unsigned long flags;
 441
 442	pm_runtime_get_sync(up->dev);
 443	spin_lock_irqsave(&up->port.lock, flags);
 444	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
 445	serial_out(up, UART_IER, up->ier);
 446	spin_unlock_irqrestore(&up->port.lock, flags);
 447	pm_runtime_mark_last_busy(up->dev);
 448	pm_runtime_put_autosuspend(up->dev);
 449}
 450
 451static void serial_omap_unthrottle(struct uart_port *port)
 452{
 453	struct uart_omap_port *up = to_uart_omap_port(port);
 454	unsigned long flags;
 455
 456	pm_runtime_get_sync(up->dev);
 457	spin_lock_irqsave(&up->port.lock, flags);
 458	up->ier |= UART_IER_RLSI | UART_IER_RDI;
 459	serial_out(up, UART_IER, up->ier);
 460	spin_unlock_irqrestore(&up->port.lock, flags);
 461	pm_runtime_mark_last_busy(up->dev);
 462	pm_runtime_put_autosuspend(up->dev);
 463}
 464
 465static unsigned int check_modem_status(struct uart_omap_port *up)
 466{
 467	unsigned int status;
 468
 469	status = serial_in(up, UART_MSR);
 470	status |= up->msr_saved_flags;
 471	up->msr_saved_flags = 0;
 472	if ((status & UART_MSR_ANY_DELTA) == 0)
 473		return status;
 474
 475	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
 476	    up->port.state != NULL) {
 477		if (status & UART_MSR_TERI)
 478			up->port.icount.rng++;
 479		if (status & UART_MSR_DDSR)
 480			up->port.icount.dsr++;
 481		if (status & UART_MSR_DDCD)
 482			uart_handle_dcd_change
 483				(&up->port, status & UART_MSR_DCD);
 484		if (status & UART_MSR_DCTS)
 485			uart_handle_cts_change
 486				(&up->port, status & UART_MSR_CTS);
 487		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 488	}
 489
 490	return status;
 491}
 492
 493static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
 494{
 495	unsigned int flag;
 496	unsigned char ch = 0;
 497
 
 
 
 
 498	if (likely(lsr & UART_LSR_DR))
 499		ch = serial_in(up, UART_RX);
 500
 501	up->port.icount.rx++;
 502	flag = TTY_NORMAL;
 503
 504	if (lsr & UART_LSR_BI) {
 505		flag = TTY_BREAK;
 506		lsr &= ~(UART_LSR_FE | UART_LSR_PE);
 507		up->port.icount.brk++;
 508		/*
 509		 * We do the SysRQ and SAK checking
 510		 * here because otherwise the break
 511		 * may get masked by ignore_status_mask
 512		 * or read_status_mask.
 513		 */
 514		if (uart_handle_break(&up->port))
 515			return;
 516
 517	}
 518
 519	if (lsr & UART_LSR_PE) {
 520		flag = TTY_PARITY;
 521		up->port.icount.parity++;
 522	}
 523
 524	if (lsr & UART_LSR_FE) {
 525		flag = TTY_FRAME;
 526		up->port.icount.frame++;
 527	}
 528
 529	if (lsr & UART_LSR_OE)
 530		up->port.icount.overrun++;
 531
 532#ifdef CONFIG_SERIAL_OMAP_CONSOLE
 533	if (up->port.line == up->port.cons->index) {
 534		/* Recover the break flag from console xmit */
 535		lsr |= up->lsr_break_flag;
 536	}
 537#endif
 538	uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
 539}
 540
 541static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
 542{
 543	unsigned char ch = 0;
 544	unsigned int flag;
 545
 546	if (!(lsr & UART_LSR_DR))
 547		return;
 548
 549	ch = serial_in(up, UART_RX);
 550	flag = TTY_NORMAL;
 551	up->port.icount.rx++;
 552
 553	if (uart_handle_sysrq_char(&up->port, ch))
 554		return;
 555
 556	uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
 557}
 558
 559/**
 560 * serial_omap_irq() - This handles the interrupt from one port
 561 * @irq: uart port irq number
 562 * @dev_id: uart port info
 563 */
 564static irqreturn_t serial_omap_irq(int irq, void *dev_id)
 565{
 566	struct uart_omap_port *up = dev_id;
 567	unsigned int iir, lsr;
 568	unsigned int type;
 569	irqreturn_t ret = IRQ_NONE;
 570	int max_count = 256;
 571
 572	spin_lock(&up->port.lock);
 573	pm_runtime_get_sync(up->dev);
 574
 575	do {
 576		iir = serial_in(up, UART_IIR);
 577		if (iir & UART_IIR_NO_INT)
 578			break;
 579
 580		ret = IRQ_HANDLED;
 581		lsr = serial_in(up, UART_LSR);
 582
 583		/* extract IRQ type from IIR register */
 584		type = iir & 0x3e;
 585
 586		switch (type) {
 587		case UART_IIR_MSI:
 588			check_modem_status(up);
 589			break;
 590		case UART_IIR_THRI:
 591			transmit_chars(up, lsr);
 592			break;
 593		case UART_IIR_RX_TIMEOUT:
 594			/* FALLTHROUGH */
 595		case UART_IIR_RDI:
 596			serial_omap_rdi(up, lsr);
 597			break;
 598		case UART_IIR_RLSI:
 599			serial_omap_rlsi(up, lsr);
 600			break;
 601		case UART_IIR_CTS_RTS_DSR:
 602			/* simply try again */
 603			break;
 604		case UART_IIR_XOFF:
 605			/* FALLTHROUGH */
 606		default:
 607			break;
 608		}
 609	} while (max_count--);
 610
 611	spin_unlock(&up->port.lock);
 612
 613	tty_flip_buffer_push(&up->port.state->port);
 614
 615	pm_runtime_mark_last_busy(up->dev);
 616	pm_runtime_put_autosuspend(up->dev);
 617	up->port_activity = jiffies;
 618
 619	return ret;
 620}
 621
 622static unsigned int serial_omap_tx_empty(struct uart_port *port)
 623{
 624	struct uart_omap_port *up = to_uart_omap_port(port);
 625	unsigned long flags = 0;
 626	unsigned int ret = 0;
 627
 628	pm_runtime_get_sync(up->dev);
 629	dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
 630	spin_lock_irqsave(&up->port.lock, flags);
 631	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
 632	spin_unlock_irqrestore(&up->port.lock, flags);
 633	pm_runtime_mark_last_busy(up->dev);
 634	pm_runtime_put_autosuspend(up->dev);
 635	return ret;
 636}
 637
 638static unsigned int serial_omap_get_mctrl(struct uart_port *port)
 639{
 640	struct uart_omap_port *up = to_uart_omap_port(port);
 641	unsigned int status;
 642	unsigned int ret = 0;
 643
 644	pm_runtime_get_sync(up->dev);
 645	status = check_modem_status(up);
 646	pm_runtime_mark_last_busy(up->dev);
 647	pm_runtime_put_autosuspend(up->dev);
 648
 649	dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
 650
 651	if (status & UART_MSR_DCD)
 652		ret |= TIOCM_CAR;
 653	if (status & UART_MSR_RI)
 654		ret |= TIOCM_RNG;
 655	if (status & UART_MSR_DSR)
 656		ret |= TIOCM_DSR;
 657	if (status & UART_MSR_CTS)
 658		ret |= TIOCM_CTS;
 659	return ret;
 660}
 661
 662static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
 663{
 664	struct uart_omap_port *up = to_uart_omap_port(port);
 665	unsigned char mcr = 0, old_mcr, lcr;
 666
 667	dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
 668	if (mctrl & TIOCM_RTS)
 669		mcr |= UART_MCR_RTS;
 670	if (mctrl & TIOCM_DTR)
 671		mcr |= UART_MCR_DTR;
 672	if (mctrl & TIOCM_OUT1)
 673		mcr |= UART_MCR_OUT1;
 674	if (mctrl & TIOCM_OUT2)
 675		mcr |= UART_MCR_OUT2;
 676	if (mctrl & TIOCM_LOOP)
 677		mcr |= UART_MCR_LOOP;
 678
 679	pm_runtime_get_sync(up->dev);
 680	old_mcr = serial_in(up, UART_MCR);
 681	old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
 682		     UART_MCR_DTR | UART_MCR_RTS);
 683	up->mcr = old_mcr | mcr;
 684	serial_out(up, UART_MCR, up->mcr);
 685
 686	/* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
 687	lcr = serial_in(up, UART_LCR);
 688	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 689	if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
 690		up->efr |= UART_EFR_RTS;
 691	else
 692		up->efr &= ~UART_EFR_RTS;
 693	serial_out(up, UART_EFR, up->efr);
 694	serial_out(up, UART_LCR, lcr);
 695
 696	pm_runtime_mark_last_busy(up->dev);
 697	pm_runtime_put_autosuspend(up->dev);
 698}
 699
 700static void serial_omap_break_ctl(struct uart_port *port, int break_state)
 701{
 702	struct uart_omap_port *up = to_uart_omap_port(port);
 703	unsigned long flags = 0;
 704
 705	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
 706	pm_runtime_get_sync(up->dev);
 707	spin_lock_irqsave(&up->port.lock, flags);
 708	if (break_state == -1)
 709		up->lcr |= UART_LCR_SBC;
 710	else
 711		up->lcr &= ~UART_LCR_SBC;
 712	serial_out(up, UART_LCR, up->lcr);
 713	spin_unlock_irqrestore(&up->port.lock, flags);
 714	pm_runtime_mark_last_busy(up->dev);
 715	pm_runtime_put_autosuspend(up->dev);
 716}
 717
 718static int serial_omap_startup(struct uart_port *port)
 719{
 720	struct uart_omap_port *up = to_uart_omap_port(port);
 721	unsigned long flags = 0;
 722	int retval;
 723
 724	/*
 725	 * Allocate the IRQ
 726	 */
 727	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
 728				up->name, up);
 729	if (retval)
 730		return retval;
 731
 732	/* Optional wake-up IRQ */
 733	if (up->wakeirq) {
 734		retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
 735		if (retval) {
 736			free_irq(up->port.irq, up);
 737			return retval;
 738		}
 739	}
 740
 741	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
 742
 743	pm_runtime_get_sync(up->dev);
 744	/*
 745	 * Clear the FIFO buffers and disable them.
 746	 * (they will be reenabled in set_termios())
 747	 */
 748	serial_omap_clear_fifos(up);
 749
 750	/*
 751	 * Clear the interrupt registers.
 752	 */
 753	(void) serial_in(up, UART_LSR);
 754	if (serial_in(up, UART_LSR) & UART_LSR_DR)
 755		(void) serial_in(up, UART_RX);
 756	(void) serial_in(up, UART_IIR);
 757	(void) serial_in(up, UART_MSR);
 758
 759	/*
 760	 * Now, initialize the UART
 761	 */
 762	serial_out(up, UART_LCR, UART_LCR_WLEN8);
 763	spin_lock_irqsave(&up->port.lock, flags);
 764	/*
 765	 * Most PC uarts need OUT2 raised to enable interrupts.
 766	 */
 767	up->port.mctrl |= TIOCM_OUT2;
 768	serial_omap_set_mctrl(&up->port, up->port.mctrl);
 769	spin_unlock_irqrestore(&up->port.lock, flags);
 770
 771	up->msr_saved_flags = 0;
 772	/*
 773	 * Finally, enable interrupts. Note: Modem status interrupts
 774	 * are set via set_termios(), which will be occurring imminently
 775	 * anyway, so we don't enable them here.
 776	 */
 777	up->ier = UART_IER_RLSI | UART_IER_RDI;
 778	serial_out(up, UART_IER, up->ier);
 779
 780	/* Enable module level wake up */
 781	up->wer = OMAP_UART_WER_MOD_WKUP;
 782	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
 783		up->wer |= OMAP_UART_TX_WAKEUP_EN;
 784
 785	serial_out(up, UART_OMAP_WER, up->wer);
 786
 787	pm_runtime_mark_last_busy(up->dev);
 788	pm_runtime_put_autosuspend(up->dev);
 789	up->port_activity = jiffies;
 790	return 0;
 791}
 792
 793static void serial_omap_shutdown(struct uart_port *port)
 794{
 795	struct uart_omap_port *up = to_uart_omap_port(port);
 796	unsigned long flags = 0;
 797
 798	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
 799
 800	pm_runtime_get_sync(up->dev);
 801	/*
 802	 * Disable interrupts from this port
 803	 */
 804	up->ier = 0;
 805	serial_out(up, UART_IER, 0);
 806
 807	spin_lock_irqsave(&up->port.lock, flags);
 808	up->port.mctrl &= ~TIOCM_OUT2;
 809	serial_omap_set_mctrl(&up->port, up->port.mctrl);
 810	spin_unlock_irqrestore(&up->port.lock, flags);
 811
 812	/*
 813	 * Disable break condition and FIFOs
 814	 */
 815	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
 816	serial_omap_clear_fifos(up);
 817
 818	/*
 819	 * Read data port to reset things, and then free the irq
 820	 */
 821	if (serial_in(up, UART_LSR) & UART_LSR_DR)
 822		(void) serial_in(up, UART_RX);
 823
 824	pm_runtime_mark_last_busy(up->dev);
 825	pm_runtime_put_autosuspend(up->dev);
 826	free_irq(up->port.irq, up);
 827	dev_pm_clear_wake_irq(up->dev);
 828}
 829
 830static void serial_omap_uart_qos_work(struct work_struct *work)
 831{
 832	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
 833						qos_work);
 834
 835	pm_qos_update_request(&up->pm_qos_request, up->latency);
 836}
 837
 838static void
 839serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 840			struct ktermios *old)
 841{
 842	struct uart_omap_port *up = to_uart_omap_port(port);
 843	unsigned char cval = 0;
 844	unsigned long flags = 0;
 845	unsigned int baud, quot;
 846
 847	switch (termios->c_cflag & CSIZE) {
 848	case CS5:
 849		cval = UART_LCR_WLEN5;
 850		break;
 851	case CS6:
 852		cval = UART_LCR_WLEN6;
 853		break;
 854	case CS7:
 855		cval = UART_LCR_WLEN7;
 856		break;
 857	default:
 858	case CS8:
 859		cval = UART_LCR_WLEN8;
 860		break;
 861	}
 862
 863	if (termios->c_cflag & CSTOPB)
 864		cval |= UART_LCR_STOP;
 865	if (termios->c_cflag & PARENB)
 866		cval |= UART_LCR_PARITY;
 867	if (!(termios->c_cflag & PARODD))
 868		cval |= UART_LCR_EPAR;
 869	if (termios->c_cflag & CMSPAR)
 870		cval |= UART_LCR_SPAR;
 871
 872	/*
 873	 * Ask the core to calculate the divisor for us.
 874	 */
 875
 876	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
 877	quot = serial_omap_get_divisor(port, baud);
 878
 879	/* calculate wakeup latency constraint */
 880	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
 881	up->latency = up->calc_latency;
 882	schedule_work(&up->qos_work);
 883
 884	up->dll = quot & 0xff;
 885	up->dlh = quot >> 8;
 886	up->mdr1 = UART_OMAP_MDR1_DISABLE;
 887
 888	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
 889			UART_FCR_ENABLE_FIFO;
 890
 891	/*
 892	 * Ok, we're now changing the port state. Do it with
 893	 * interrupts disabled.
 894	 */
 895	pm_runtime_get_sync(up->dev);
 896	spin_lock_irqsave(&up->port.lock, flags);
 897
 898	/*
 899	 * Update the per-port timeout.
 900	 */
 901	uart_update_timeout(port, termios->c_cflag, baud);
 902
 903	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
 904	if (termios->c_iflag & INPCK)
 905		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 906	if (termios->c_iflag & (BRKINT | PARMRK))
 907		up->port.read_status_mask |= UART_LSR_BI;
 908
 909	/*
 910	 * Characters to ignore
 911	 */
 912	up->port.ignore_status_mask = 0;
 913	if (termios->c_iflag & IGNPAR)
 914		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 915	if (termios->c_iflag & IGNBRK) {
 916		up->port.ignore_status_mask |= UART_LSR_BI;
 917		/*
 918		 * If we're ignoring parity and break indicators,
 919		 * ignore overruns too (for real raw support).
 920		 */
 921		if (termios->c_iflag & IGNPAR)
 922			up->port.ignore_status_mask |= UART_LSR_OE;
 923	}
 924
 925	/*
 926	 * ignore all characters if CREAD is not set
 927	 */
 928	if ((termios->c_cflag & CREAD) == 0)
 929		up->port.ignore_status_mask |= UART_LSR_DR;
 930
 931	/*
 932	 * Modem status interrupts
 933	 */
 934	up->ier &= ~UART_IER_MSI;
 935	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
 936		up->ier |= UART_IER_MSI;
 937	serial_out(up, UART_IER, up->ier);
 938	serial_out(up, UART_LCR, cval);		/* reset DLAB */
 939	up->lcr = cval;
 940	up->scr = 0;
 941
 942	/* FIFOs and DMA Settings */
 943
 944	/* FCR can be changed only when the
 945	 * baud clock is not running
 946	 * DLL_REG and DLH_REG set to 0.
 947	 */
 948	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 949	serial_out(up, UART_DLL, 0);
 950	serial_out(up, UART_DLM, 0);
 951	serial_out(up, UART_LCR, 0);
 952
 953	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 954
 955	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
 956	up->efr &= ~UART_EFR_SCD;
 957	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 958
 959	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 960	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
 961	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 962	/* FIFO ENABLE, DMA MODE */
 963
 964	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
 965	/*
 966	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
 967	 * sets Enables the granularity of 1 for TRIGGER RX
 968	 * level. Along with setting RX FIFO trigger level
 969	 * to 1 (as noted below, 16 characters) and TLR[3:0]
 970	 * to zero this will result RX FIFO threshold level
 971	 * to 1 character, instead of 16 as noted in comment
 972	 * below.
 973	 */
 974
 975	/* Set receive FIFO threshold to 16 characters and
 976	 * transmit FIFO threshold to 32 spaces
 977	 */
 978	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
 979	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
 980	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
 981		UART_FCR_ENABLE_FIFO;
 982
 983	serial_out(up, UART_FCR, up->fcr);
 984	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 985
 986	serial_out(up, UART_OMAP_SCR, up->scr);
 987
 988	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
 989	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 990	serial_out(up, UART_MCR, up->mcr);
 991	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 992	serial_out(up, UART_EFR, up->efr);
 993	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 994
 995	/* Protocol, Baud Rate, and Interrupt Settings */
 996
 997	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
 998		serial_omap_mdr1_errataset(up, up->mdr1);
 999	else
1000		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1001
1002	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1003	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1004
1005	serial_out(up, UART_LCR, 0);
1006	serial_out(up, UART_IER, 0);
1007	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1008
1009	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
1010	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
1011
1012	serial_out(up, UART_LCR, 0);
1013	serial_out(up, UART_IER, up->ier);
1014	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1015
1016	serial_out(up, UART_EFR, up->efr);
1017	serial_out(up, UART_LCR, cval);
1018
1019	if (!serial_omap_baud_is_mode16(port, baud))
1020		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1021	else
1022		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1023
1024	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1025		serial_omap_mdr1_errataset(up, up->mdr1);
1026	else
1027		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1028
1029	/* Configure flow control */
1030	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1031
1032	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1033	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1034	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1035
1036	/* Enable access to TCR/TLR */
1037	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1038	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1039	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1040
1041	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1042
1043	up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
1044
1045	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1046		/* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
1047		up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
1048		up->efr |= UART_EFR_CTS;
1049	} else {
1050		/* Disable AUTORTS and AUTOCTS */
1051		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1052	}
1053
1054	if (up->port.flags & UPF_SOFT_FLOW) {
1055		/* clear SW control mode bits */
1056		up->efr &= OMAP_UART_SW_CLR;
1057
1058		/*
1059		 * IXON Flag:
1060		 * Enable XON/XOFF flow control on input.
1061		 * Receiver compares XON1, XOFF1.
1062		 */
1063		if (termios->c_iflag & IXON)
1064			up->efr |= OMAP_UART_SW_RX;
1065
1066		/*
1067		 * IXOFF Flag:
1068		 * Enable XON/XOFF flow control on output.
1069		 * Transmit XON1, XOFF1
1070		 */
1071		if (termios->c_iflag & IXOFF) {
1072			up->port.status |= UPSTAT_AUTOXOFF;
1073			up->efr |= OMAP_UART_SW_TX;
1074		}
1075
1076		/*
1077		 * IXANY Flag:
1078		 * Enable any character to restart output.
1079		 * Operation resumes after receiving any
1080		 * character after recognition of the XOFF character
1081		 */
1082		if (termios->c_iflag & IXANY)
1083			up->mcr |= UART_MCR_XONANY;
1084		else
1085			up->mcr &= ~UART_MCR_XONANY;
1086	}
1087	serial_out(up, UART_MCR, up->mcr);
1088	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1089	serial_out(up, UART_EFR, up->efr);
1090	serial_out(up, UART_LCR, up->lcr);
1091
1092	serial_omap_set_mctrl(&up->port, up->port.mctrl);
1093
1094	spin_unlock_irqrestore(&up->port.lock, flags);
1095	pm_runtime_mark_last_busy(up->dev);
1096	pm_runtime_put_autosuspend(up->dev);
1097	dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1098}
1099
1100static void
1101serial_omap_pm(struct uart_port *port, unsigned int state,
1102	       unsigned int oldstate)
1103{
1104	struct uart_omap_port *up = to_uart_omap_port(port);
1105	unsigned char efr;
1106
1107	dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1108
1109	pm_runtime_get_sync(up->dev);
1110	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1111	efr = serial_in(up, UART_EFR);
1112	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1113	serial_out(up, UART_LCR, 0);
1114
1115	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1116	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1117	serial_out(up, UART_EFR, efr);
1118	serial_out(up, UART_LCR, 0);
1119
1120	pm_runtime_mark_last_busy(up->dev);
1121	pm_runtime_put_autosuspend(up->dev);
1122}
1123
1124static void serial_omap_release_port(struct uart_port *port)
1125{
1126	dev_dbg(port->dev, "serial_omap_release_port+\n");
1127}
1128
1129static int serial_omap_request_port(struct uart_port *port)
1130{
1131	dev_dbg(port->dev, "serial_omap_request_port+\n");
1132	return 0;
1133}
1134
1135static void serial_omap_config_port(struct uart_port *port, int flags)
1136{
1137	struct uart_omap_port *up = to_uart_omap_port(port);
1138
1139	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1140							up->port.line);
1141	up->port.type = PORT_OMAP;
1142	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1143}
1144
1145static int
1146serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1147{
1148	/* we don't want the core code to modify any port params */
1149	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1150	return -EINVAL;
1151}
1152
1153static const char *
1154serial_omap_type(struct uart_port *port)
1155{
1156	struct uart_omap_port *up = to_uart_omap_port(port);
1157
1158	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1159	return up->name;
1160}
1161
1162#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1163
1164static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
1165{
1166	unsigned int status, tmout = 10000;
1167
1168	/* Wait up to 10ms for the character(s) to be sent. */
1169	do {
1170		status = serial_in(up, UART_LSR);
1171
1172		if (status & UART_LSR_BI)
1173			up->lsr_break_flag = UART_LSR_BI;
1174
1175		if (--tmout == 0)
1176			break;
1177		udelay(1);
1178	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1179
1180	/* Wait up to 1s for flow control if necessary */
1181	if (up->port.flags & UPF_CONS_FLOW) {
1182		tmout = 1000000;
1183		for (tmout = 1000000; tmout; tmout--) {
1184			unsigned int msr = serial_in(up, UART_MSR);
1185
1186			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1187			if (msr & UART_MSR_CTS)
1188				break;
1189
1190			udelay(1);
1191		}
1192	}
1193}
1194
1195#ifdef CONFIG_CONSOLE_POLL
1196
1197static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1198{
1199	struct uart_omap_port *up = to_uart_omap_port(port);
1200
1201	pm_runtime_get_sync(up->dev);
1202	wait_for_xmitr(up);
1203	serial_out(up, UART_TX, ch);
1204	pm_runtime_mark_last_busy(up->dev);
1205	pm_runtime_put_autosuspend(up->dev);
1206}
1207
1208static int serial_omap_poll_get_char(struct uart_port *port)
1209{
1210	struct uart_omap_port *up = to_uart_omap_port(port);
1211	unsigned int status;
1212
1213	pm_runtime_get_sync(up->dev);
1214	status = serial_in(up, UART_LSR);
1215	if (!(status & UART_LSR_DR)) {
1216		status = NO_POLL_CHAR;
1217		goto out;
1218	}
1219
1220	status = serial_in(up, UART_RX);
1221
1222out:
1223	pm_runtime_mark_last_busy(up->dev);
1224	pm_runtime_put_autosuspend(up->dev);
1225
1226	return status;
1227}
1228
1229#endif /* CONFIG_CONSOLE_POLL */
1230
1231#ifdef CONFIG_SERIAL_OMAP_CONSOLE
1232
1233#ifdef CONFIG_SERIAL_EARLYCON
1234static unsigned int omap_serial_early_in(struct uart_port *port, int offset)
1235{
1236	offset <<= port->regshift;
1237	return readw(port->membase + offset);
1238}
1239
1240static void omap_serial_early_out(struct uart_port *port, int offset,
1241				  int value)
1242{
1243	offset <<= port->regshift;
1244	writew(value, port->membase + offset);
1245}
1246
1247static void omap_serial_early_putc(struct uart_port *port, int c)
1248{
1249	unsigned int status;
1250
1251	for (;;) {
1252		status = omap_serial_early_in(port, UART_LSR);
1253		if ((status & BOTH_EMPTY) == BOTH_EMPTY)
1254			break;
1255		cpu_relax();
1256	}
1257	omap_serial_early_out(port, UART_TX, c);
1258}
1259
1260static void early_omap_serial_write(struct console *console, const char *s,
1261				    unsigned int count)
1262{
1263	struct earlycon_device *device = console->data;
1264	struct uart_port *port = &device->port;
1265
1266	uart_console_write(port, s, count, omap_serial_early_putc);
1267}
1268
1269static int __init early_omap_serial_setup(struct earlycon_device *device,
1270					  const char *options)
1271{
1272	struct uart_port *port = &device->port;
1273
1274	if (!(device->port.membase || device->port.iobase))
1275		return -ENODEV;
1276
1277	port->regshift = 2;
1278	device->con->write = early_omap_serial_write;
1279	return 0;
1280}
1281
1282OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup);
1283OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup);
1284OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup);
1285#endif /* CONFIG_SERIAL_EARLYCON */
1286
1287static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1288
1289static struct uart_driver serial_omap_reg;
1290
1291static void serial_omap_console_putchar(struct uart_port *port, int ch)
1292{
1293	struct uart_omap_port *up = to_uart_omap_port(port);
1294
1295	wait_for_xmitr(up);
1296	serial_out(up, UART_TX, ch);
1297}
1298
1299static void
1300serial_omap_console_write(struct console *co, const char *s,
1301		unsigned int count)
1302{
1303	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1304	unsigned long flags;
1305	unsigned int ier;
1306	int locked = 1;
1307
1308	pm_runtime_get_sync(up->dev);
1309
1310	local_irq_save(flags);
1311	if (up->port.sysrq)
1312		locked = 0;
1313	else if (oops_in_progress)
1314		locked = spin_trylock(&up->port.lock);
1315	else
1316		spin_lock(&up->port.lock);
1317
1318	/*
1319	 * First save the IER then disable the interrupts
1320	 */
1321	ier = serial_in(up, UART_IER);
1322	serial_out(up, UART_IER, 0);
1323
1324	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1325
1326	/*
1327	 * Finally, wait for transmitter to become empty
1328	 * and restore the IER
1329	 */
1330	wait_for_xmitr(up);
1331	serial_out(up, UART_IER, ier);
1332	/*
1333	 * The receive handling will happen properly because the
1334	 * receive ready bit will still be set; it is not cleared
1335	 * on read.  However, modem control will not, we must
1336	 * call it if we have saved something in the saved flags
1337	 * while processing with interrupts off.
1338	 */
1339	if (up->msr_saved_flags)
1340		check_modem_status(up);
1341
1342	pm_runtime_mark_last_busy(up->dev);
1343	pm_runtime_put_autosuspend(up->dev);
1344	if (locked)
1345		spin_unlock(&up->port.lock);
1346	local_irq_restore(flags);
1347}
1348
1349static int __init
1350serial_omap_console_setup(struct console *co, char *options)
1351{
1352	struct uart_omap_port *up;
1353	int baud = 115200;
1354	int bits = 8;
1355	int parity = 'n';
1356	int flow = 'n';
1357
1358	if (serial_omap_console_ports[co->index] == NULL)
1359		return -ENODEV;
1360	up = serial_omap_console_ports[co->index];
1361
1362	if (options)
1363		uart_parse_options(options, &baud, &parity, &bits, &flow);
1364
1365	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1366}
1367
1368static struct console serial_omap_console = {
1369	.name		= OMAP_SERIAL_NAME,
1370	.write		= serial_omap_console_write,
1371	.device		= uart_console_device,
1372	.setup		= serial_omap_console_setup,
1373	.flags		= CON_PRINTBUFFER,
1374	.index		= -1,
1375	.data		= &serial_omap_reg,
1376};
1377
1378static void serial_omap_add_console_port(struct uart_omap_port *up)
1379{
1380	serial_omap_console_ports[up->port.line] = up;
1381}
1382
1383#define OMAP_CONSOLE	(&serial_omap_console)
1384
1385#else
1386
1387#define OMAP_CONSOLE	NULL
1388
1389static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1390{}
1391
1392#endif
1393
1394/* Enable or disable the rs485 support */
1395static int
1396serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
1397{
1398	struct uart_omap_port *up = to_uart_omap_port(port);
1399	unsigned int mode;
1400	int val;
1401
1402	pm_runtime_get_sync(up->dev);
1403
1404	/* Disable interrupts from this port */
1405	mode = up->ier;
1406	up->ier = 0;
1407	serial_out(up, UART_IER, 0);
1408
1409	/* Clamp the delays to [0, 100ms] */
1410	rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
1411	rs485->delay_rts_after_send  = min(rs485->delay_rts_after_send, 100U);
1412
1413	/* store new config */
1414	port->rs485 = *rs485;
1415
1416	/*
1417	 * Just as a precaution, only allow rs485
1418	 * to be enabled if the gpio pin is valid
1419	 */
1420	if (gpio_is_valid(up->rts_gpio)) {
1421		/* enable / disable rts */
1422		val = (port->rs485.flags & SER_RS485_ENABLED) ?
1423			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1424		val = (port->rs485.flags & val) ? 1 : 0;
1425		gpio_set_value(up->rts_gpio, val);
1426	} else
1427		port->rs485.flags &= ~SER_RS485_ENABLED;
1428
1429	/* Enable interrupts */
1430	up->ier = mode;
1431	serial_out(up, UART_IER, up->ier);
1432
1433	/* If RS-485 is disabled, make sure the THR interrupt is fired when
1434	 * TX FIFO is below the trigger level.
1435	 */
1436	if (!(port->rs485.flags & SER_RS485_ENABLED) &&
1437	    (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1438		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1439		serial_out(up, UART_OMAP_SCR, up->scr);
1440	}
1441
1442	pm_runtime_mark_last_busy(up->dev);
1443	pm_runtime_put_autosuspend(up->dev);
1444
1445	return 0;
1446}
1447
1448static const struct uart_ops serial_omap_pops = {
1449	.tx_empty	= serial_omap_tx_empty,
1450	.set_mctrl	= serial_omap_set_mctrl,
1451	.get_mctrl	= serial_omap_get_mctrl,
1452	.stop_tx	= serial_omap_stop_tx,
1453	.start_tx	= serial_omap_start_tx,
1454	.throttle	= serial_omap_throttle,
1455	.unthrottle	= serial_omap_unthrottle,
1456	.stop_rx	= serial_omap_stop_rx,
1457	.enable_ms	= serial_omap_enable_ms,
1458	.break_ctl	= serial_omap_break_ctl,
1459	.startup	= serial_omap_startup,
1460	.shutdown	= serial_omap_shutdown,
1461	.set_termios	= serial_omap_set_termios,
1462	.pm		= serial_omap_pm,
1463	.type		= serial_omap_type,
1464	.release_port	= serial_omap_release_port,
1465	.request_port	= serial_omap_request_port,
1466	.config_port	= serial_omap_config_port,
1467	.verify_port	= serial_omap_verify_port,
1468#ifdef CONFIG_CONSOLE_POLL
1469	.poll_put_char  = serial_omap_poll_put_char,
1470	.poll_get_char  = serial_omap_poll_get_char,
1471#endif
1472};
1473
1474static struct uart_driver serial_omap_reg = {
1475	.owner		= THIS_MODULE,
1476	.driver_name	= "OMAP-SERIAL",
1477	.dev_name	= OMAP_SERIAL_NAME,
1478	.nr		= OMAP_MAX_HSUART_PORTS,
1479	.cons		= OMAP_CONSOLE,
1480};
1481
1482#ifdef CONFIG_PM_SLEEP
1483static int serial_omap_prepare(struct device *dev)
1484{
1485	struct uart_omap_port *up = dev_get_drvdata(dev);
1486
1487	up->is_suspending = true;
1488
1489	return 0;
1490}
1491
1492static void serial_omap_complete(struct device *dev)
1493{
1494	struct uart_omap_port *up = dev_get_drvdata(dev);
1495
1496	up->is_suspending = false;
1497}
1498
1499static int serial_omap_suspend(struct device *dev)
1500{
1501	struct uart_omap_port *up = dev_get_drvdata(dev);
1502
1503	uart_suspend_port(&serial_omap_reg, &up->port);
1504	flush_work(&up->qos_work);
1505
1506	if (device_may_wakeup(dev))
1507		serial_omap_enable_wakeup(up, true);
1508	else
1509		serial_omap_enable_wakeup(up, false);
1510
1511	return 0;
1512}
1513
1514static int serial_omap_resume(struct device *dev)
1515{
1516	struct uart_omap_port *up = dev_get_drvdata(dev);
1517
1518	if (device_may_wakeup(dev))
1519		serial_omap_enable_wakeup(up, false);
1520
1521	uart_resume_port(&serial_omap_reg, &up->port);
1522
1523	return 0;
1524}
1525#else
1526#define serial_omap_prepare NULL
1527#define serial_omap_complete NULL
1528#endif /* CONFIG_PM_SLEEP */
1529
1530static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1531{
1532	u32 mvr, scheme;
1533	u16 revision, major, minor;
1534
1535	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1536
1537	/* Check revision register scheme */
1538	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1539
1540	switch (scheme) {
1541	case 0: /* Legacy Scheme: OMAP2/3 */
1542		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1543		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1544					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1545		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1546		break;
1547	case 1:
1548		/* New Scheme: OMAP4+ */
1549		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1550		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1551					OMAP_UART_MVR_MAJ_SHIFT;
1552		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1553		break;
1554	default:
1555		dev_warn(up->dev,
1556			"Unknown %s revision, defaulting to highest\n",
1557			up->name);
1558		/* highest possible revision */
1559		major = 0xff;
1560		minor = 0xff;
1561	}
1562
1563	/* normalize revision for the driver */
1564	revision = UART_BUILD_REVISION(major, minor);
1565
1566	switch (revision) {
1567	case OMAP_UART_REV_46:
1568		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1569				UART_ERRATA_i291_DMA_FORCEIDLE);
1570		break;
1571	case OMAP_UART_REV_52:
1572		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1573				UART_ERRATA_i291_DMA_FORCEIDLE);
1574		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1575		break;
1576	case OMAP_UART_REV_63:
1577		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1578		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1579		break;
1580	default:
1581		break;
1582	}
1583}
1584
1585static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1586{
1587	struct omap_uart_port_info *omap_up_info;
1588
1589	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1590	if (!omap_up_info)
1591		return NULL; /* out of memory */
1592
1593	of_property_read_u32(dev->of_node, "clock-frequency",
1594					 &omap_up_info->uartclk);
1595
1596	omap_up_info->flags = UPF_BOOT_AUTOCONF;
1597
1598	return omap_up_info;
1599}
1600
1601static int serial_omap_probe_rs485(struct uart_omap_port *up,
1602				   struct device_node *np)
1603{
1604	struct serial_rs485 *rs485conf = &up->port.rs485;
 
 
1605	int ret;
1606
1607	rs485conf->flags = 0;
1608	up->rts_gpio = -EINVAL;
1609
1610	if (!np)
1611		return 0;
1612
1613	uart_get_rs485_mode(up->dev, rs485conf);
 
 
1614
1615	if (of_property_read_bool(np, "rs485-rts-active-high")) {
1616		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1617		rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND;
1618	} else {
1619		rs485conf->flags &= ~SER_RS485_RTS_ON_SEND;
1620		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1621	}
1622
1623	/* check for tx enable gpio */
1624	up->rts_gpio = of_get_named_gpio(np, "rts-gpio", 0);
1625	if (gpio_is_valid(up->rts_gpio)) {
1626		ret = devm_gpio_request(up->dev, up->rts_gpio, "omap-serial");
1627		if (ret < 0)
1628			return ret;
1629		ret = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ? 1 : 0;
1630		ret = gpio_direction_output(up->rts_gpio, ret);
1631		if (ret < 0)
1632			return ret;
1633	} else if (up->rts_gpio == -EPROBE_DEFER) {
1634		return -EPROBE_DEFER;
 
 
 
1635	} else {
1636		up->rts_gpio = -EINVAL;
1637	}
1638
1639	return 0;
1640}
1641
1642static int serial_omap_probe(struct platform_device *pdev)
1643{
1644	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1645	struct uart_omap_port *up;
1646	struct resource *mem;
1647	void __iomem *base;
1648	int uartirq = 0;
1649	int wakeirq = 0;
1650	int ret;
1651
1652	/* The optional wakeirq may be specified in the board dts file */
1653	if (pdev->dev.of_node) {
1654		uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1655		if (!uartirq)
1656			return -EPROBE_DEFER;
1657		wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1658		omap_up_info = of_get_uart_port_info(&pdev->dev);
1659		pdev->dev.platform_data = omap_up_info;
1660	} else {
1661		uartirq = platform_get_irq(pdev, 0);
1662		if (uartirq < 0)
1663			return -EPROBE_DEFER;
1664	}
1665
1666	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1667	if (!up)
1668		return -ENOMEM;
1669
1670	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1671	base = devm_ioremap_resource(&pdev->dev, mem);
1672	if (IS_ERR(base))
1673		return PTR_ERR(base);
1674
1675	up->dev = &pdev->dev;
1676	up->port.dev = &pdev->dev;
1677	up->port.type = PORT_OMAP;
1678	up->port.iotype = UPIO_MEM;
1679	up->port.irq = uartirq;
1680	up->port.regshift = 2;
1681	up->port.fifosize = 64;
1682	up->port.ops = &serial_omap_pops;
 
1683
1684	if (pdev->dev.of_node)
1685		ret = of_alias_get_id(pdev->dev.of_node, "serial");
1686	else
1687		ret = pdev->id;
1688
1689	if (ret < 0) {
1690		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1691			ret);
1692		goto err_port_line;
1693	}
1694	up->port.line = ret;
1695
1696	if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1697		dev_err(&pdev->dev, "uart ID %d >  MAX %d.\n", up->port.line,
1698			OMAP_MAX_HSUART_PORTS);
1699		ret = -ENXIO;
1700		goto err_port_line;
1701	}
1702
1703	up->wakeirq = wakeirq;
1704	if (!up->wakeirq)
1705		dev_info(up->port.dev, "no wakeirq for uart%d\n",
1706			 up->port.line);
1707
1708	ret = serial_omap_probe_rs485(up, pdev->dev.of_node);
1709	if (ret < 0)
1710		goto err_rs485;
1711
1712	sprintf(up->name, "OMAP UART%d", up->port.line);
1713	up->port.mapbase = mem->start;
1714	up->port.membase = base;
1715	up->port.flags = omap_up_info->flags;
1716	up->port.uartclk = omap_up_info->uartclk;
1717	up->port.rs485_config = serial_omap_config_rs485;
1718	if (!up->port.uartclk) {
1719		up->port.uartclk = DEFAULT_CLK_SPEED;
1720		dev_warn(&pdev->dev,
1721			 "No clock speed specified: using default: %d\n",
1722			 DEFAULT_CLK_SPEED);
1723	}
1724
1725	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1726	up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1727	pm_qos_add_request(&up->pm_qos_request,
1728		PM_QOS_CPU_DMA_LATENCY, up->latency);
1729	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1730
1731	platform_set_drvdata(pdev, up);
1732	if (omap_up_info->autosuspend_timeout == 0)
1733		omap_up_info->autosuspend_timeout = -1;
1734
1735	device_init_wakeup(up->dev, true);
1736	pm_runtime_use_autosuspend(&pdev->dev);
1737	pm_runtime_set_autosuspend_delay(&pdev->dev,
1738			omap_up_info->autosuspend_timeout);
1739
1740	pm_runtime_irq_safe(&pdev->dev);
1741	pm_runtime_enable(&pdev->dev);
1742
1743	pm_runtime_get_sync(&pdev->dev);
1744
1745	omap_serial_fill_features_erratas(up);
1746
1747	ui[up->port.line] = up;
1748	serial_omap_add_console_port(up);
1749
1750	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1751	if (ret != 0)
1752		goto err_add_port;
1753
1754	pm_runtime_mark_last_busy(up->dev);
1755	pm_runtime_put_autosuspend(up->dev);
1756	return 0;
1757
1758err_add_port:
1759	pm_runtime_dont_use_autosuspend(&pdev->dev);
1760	pm_runtime_put_sync(&pdev->dev);
1761	pm_runtime_disable(&pdev->dev);
1762	pm_qos_remove_request(&up->pm_qos_request);
1763	device_init_wakeup(up->dev, false);
1764err_rs485:
1765err_port_line:
1766	return ret;
1767}
1768
1769static int serial_omap_remove(struct platform_device *dev)
1770{
1771	struct uart_omap_port *up = platform_get_drvdata(dev);
1772
1773	pm_runtime_get_sync(up->dev);
1774
1775	uart_remove_one_port(&serial_omap_reg, &up->port);
1776
1777	pm_runtime_dont_use_autosuspend(up->dev);
1778	pm_runtime_put_sync(up->dev);
1779	pm_runtime_disable(up->dev);
1780	pm_qos_remove_request(&up->pm_qos_request);
1781	device_init_wakeup(&dev->dev, false);
1782
1783	return 0;
1784}
1785
1786/*
1787 * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1788 * The access to uart register after MDR1 Access
1789 * causes UART to corrupt data.
1790 *
1791 * Need a delay =
1792 * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1793 * give 10 times as much
1794 */
1795static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1796{
1797	u8 timeout = 255;
1798
1799	serial_out(up, UART_OMAP_MDR1, mdr1);
1800	udelay(2);
1801	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1802			UART_FCR_CLEAR_RCVR);
1803	/*
1804	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1805	 * TX_FIFO_E bit is 1.
1806	 */
1807	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1808				(UART_LSR_THRE | UART_LSR_DR))) {
1809		timeout--;
1810		if (!timeout) {
1811			/* Should *never* happen. we warn and carry on */
1812			dev_crit(up->dev, "Errata i202: timedout %x\n",
1813						serial_in(up, UART_LSR));
1814			break;
1815		}
1816		udelay(1);
1817	}
1818}
1819
1820#ifdef CONFIG_PM
1821static void serial_omap_restore_context(struct uart_omap_port *up)
1822{
1823	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1824		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1825	else
1826		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1827
1828	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1829	serial_out(up, UART_EFR, UART_EFR_ECB);
1830	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1831	serial_out(up, UART_IER, 0x0);
1832	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1833	serial_out(up, UART_DLL, up->dll);
1834	serial_out(up, UART_DLM, up->dlh);
1835	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1836	serial_out(up, UART_IER, up->ier);
1837	serial_out(up, UART_FCR, up->fcr);
1838	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1839	serial_out(up, UART_MCR, up->mcr);
1840	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1841	serial_out(up, UART_OMAP_SCR, up->scr);
1842	serial_out(up, UART_EFR, up->efr);
1843	serial_out(up, UART_LCR, up->lcr);
1844	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1845		serial_omap_mdr1_errataset(up, up->mdr1);
1846	else
1847		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1848	serial_out(up, UART_OMAP_WER, up->wer);
1849}
1850
1851static int serial_omap_runtime_suspend(struct device *dev)
1852{
1853	struct uart_omap_port *up = dev_get_drvdata(dev);
1854
1855	if (!up)
1856		return -EINVAL;
1857
1858	/*
1859	* When using 'no_console_suspend', the console UART must not be
1860	* suspended. Since driver suspend is managed by runtime suspend,
1861	* preventing runtime suspend (by returning error) will keep device
1862	* active during suspend.
1863	*/
1864	if (up->is_suspending && !console_suspend_enabled &&
1865	    uart_console(&up->port))
1866		return -EBUSY;
1867
1868	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1869
1870	serial_omap_enable_wakeup(up, true);
1871
1872	up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1873	schedule_work(&up->qos_work);
1874
1875	return 0;
1876}
1877
1878static int serial_omap_runtime_resume(struct device *dev)
1879{
1880	struct uart_omap_port *up = dev_get_drvdata(dev);
1881
1882	int loss_cnt = serial_omap_get_context_loss_count(up);
1883
1884	serial_omap_enable_wakeup(up, false);
1885
1886	if (loss_cnt < 0) {
1887		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1888			loss_cnt);
1889		serial_omap_restore_context(up);
1890	} else if (up->context_loss_cnt != loss_cnt) {
1891		serial_omap_restore_context(up);
1892	}
1893	up->latency = up->calc_latency;
1894	schedule_work(&up->qos_work);
1895
1896	return 0;
1897}
1898#endif
1899
1900static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1901	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1902	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1903				serial_omap_runtime_resume, NULL)
1904	.prepare        = serial_omap_prepare,
1905	.complete       = serial_omap_complete,
1906};
1907
1908#if defined(CONFIG_OF)
1909static const struct of_device_id omap_serial_of_match[] = {
1910	{ .compatible = "ti,omap2-uart" },
1911	{ .compatible = "ti,omap3-uart" },
1912	{ .compatible = "ti,omap4-uart" },
1913	{},
1914};
1915MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1916#endif
1917
1918static struct platform_driver serial_omap_driver = {
1919	.probe          = serial_omap_probe,
1920	.remove         = serial_omap_remove,
1921	.driver		= {
1922		.name	= OMAP_SERIAL_DRIVER_NAME,
1923		.pm	= &serial_omap_dev_pm_ops,
1924		.of_match_table = of_match_ptr(omap_serial_of_match),
1925	},
1926};
1927
1928static int __init serial_omap_init(void)
1929{
1930	int ret;
1931
1932	ret = uart_register_driver(&serial_omap_reg);
1933	if (ret != 0)
1934		return ret;
1935	ret = platform_driver_register(&serial_omap_driver);
1936	if (ret != 0)
1937		uart_unregister_driver(&serial_omap_reg);
1938	return ret;
1939}
1940
1941static void __exit serial_omap_exit(void)
1942{
1943	platform_driver_unregister(&serial_omap_driver);
1944	uart_unregister_driver(&serial_omap_reg);
1945}
1946
1947module_init(serial_omap_init);
1948module_exit(serial_omap_exit);
1949
1950MODULE_DESCRIPTION("OMAP High Speed UART driver");
1951MODULE_LICENSE("GPL");
1952MODULE_AUTHOR("Texas Instruments Inc");
v5.9
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Driver for OMAP-UART controller.
   4 * Based on drivers/serial/8250.c
   5 *
   6 * Copyright (C) 2010 Texas Instruments.
   7 *
   8 * Authors:
   9 *	Govindraj R	<govindraj.raja@ti.com>
  10 *	Thara Gopinath	<thara@ti.com>
  11 *
  12 * Note: This driver is made separate from 8250 driver as we cannot
  13 * over load 8250 driver with omap platform specific configuration for
  14 * features like DMA, it makes easier to implement features like DMA and
  15 * hardware flow control and software flow control configuration with
  16 * this driver as required for the omap-platform.
  17 */
  18
 
 
 
 
  19#include <linux/module.h>
  20#include <linux/init.h>
  21#include <linux/console.h>
  22#include <linux/serial_reg.h>
  23#include <linux/delay.h>
  24#include <linux/slab.h>
  25#include <linux/tty.h>
  26#include <linux/tty_flip.h>
  27#include <linux/platform_device.h>
  28#include <linux/io.h>
  29#include <linux/clk.h>
  30#include <linux/serial_core.h>
  31#include <linux/irq.h>
  32#include <linux/pm_runtime.h>
  33#include <linux/pm_wakeirq.h>
  34#include <linux/of.h>
  35#include <linux/of_irq.h>
  36#include <linux/gpio/consumer.h>
 
  37#include <linux/platform_data/serial-omap.h>
  38
 
 
  39#define OMAP_MAX_HSUART_PORTS	10
  40
  41#define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
  42
  43#define OMAP_UART_REV_42 0x0402
  44#define OMAP_UART_REV_46 0x0406
  45#define OMAP_UART_REV_52 0x0502
  46#define OMAP_UART_REV_63 0x0603
  47
  48#define OMAP_UART_TX_WAKEUP_EN		BIT(7)
  49
  50/* Feature flags */
  51#define OMAP_UART_WER_HAS_TX_WAKEUP	BIT(0)
  52
  53#define UART_ERRATA_i202_MDR1_ACCESS	BIT(0)
  54#define UART_ERRATA_i291_DMA_FORCEIDLE	BIT(1)
  55
  56#define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
  57
  58/* SCR register bitmasks */
  59#define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK		(1 << 7)
  60#define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK		(1 << 6)
  61#define OMAP_UART_SCR_TX_EMPTY			(1 << 3)
  62
  63/* FCR register bitmasks */
  64#define OMAP_UART_FCR_RX_FIFO_TRIG_MASK			(0x3 << 6)
  65#define OMAP_UART_FCR_TX_FIFO_TRIG_MASK			(0x3 << 4)
  66
  67/* MVR register bitmasks */
  68#define OMAP_UART_MVR_SCHEME_SHIFT	30
  69
  70#define OMAP_UART_LEGACY_MVR_MAJ_MASK	0xf0
  71#define OMAP_UART_LEGACY_MVR_MAJ_SHIFT	4
  72#define OMAP_UART_LEGACY_MVR_MIN_MASK	0x0f
  73
  74#define OMAP_UART_MVR_MAJ_MASK		0x700
  75#define OMAP_UART_MVR_MAJ_SHIFT		8
  76#define OMAP_UART_MVR_MIN_MASK		0x3f
  77
  78#define OMAP_UART_DMA_CH_FREE	-1
  79
  80#define MSR_SAVE_FLAGS		UART_MSR_ANY_DELTA
  81#define OMAP_MODE13X_SPEED	230400
  82
  83/* WER = 0x7F
  84 * Enable module level wakeup in WER reg
  85 */
  86#define OMAP_UART_WER_MOD_WKUP	0x7F
  87
  88/* Enable XON/XOFF flow control on output */
  89#define OMAP_UART_SW_TX		0x08
  90
  91/* Enable XON/XOFF flow control on input */
  92#define OMAP_UART_SW_RX		0x02
  93
  94#define OMAP_UART_SW_CLR	0xF0
  95
  96#define OMAP_UART_TCR_TRIG	0x0F
  97
  98struct uart_omap_dma {
  99	u8			uart_dma_tx;
 100	u8			uart_dma_rx;
 101	int			rx_dma_channel;
 102	int			tx_dma_channel;
 103	dma_addr_t		rx_buf_dma_phys;
 104	dma_addr_t		tx_buf_dma_phys;
 105	unsigned int		uart_base;
 106	/*
 107	 * Buffer for rx dma. It is not required for tx because the buffer
 108	 * comes from port structure.
 109	 */
 110	unsigned char		*rx_buf;
 111	unsigned int		prev_rx_dma_pos;
 112	int			tx_buf_size;
 113	int			tx_dma_used;
 114	int			rx_dma_used;
 115	spinlock_t		tx_lock;
 116	spinlock_t		rx_lock;
 117	/* timer to poll activity on rx dma */
 118	struct timer_list	rx_timer;
 119	unsigned int		rx_buf_size;
 120	unsigned int		rx_poll_rate;
 121	unsigned int		rx_timeout;
 122};
 123
 124struct uart_omap_port {
 125	struct uart_port	port;
 126	struct uart_omap_dma	uart_dma;
 127	struct device		*dev;
 128	int			wakeirq;
 129
 130	unsigned char		ier;
 131	unsigned char		lcr;
 132	unsigned char		mcr;
 133	unsigned char		fcr;
 134	unsigned char		efr;
 135	unsigned char		dll;
 136	unsigned char		dlh;
 137	unsigned char		mdr1;
 138	unsigned char		scr;
 139	unsigned char		wer;
 140
 141	int			use_dma;
 142	/*
 143	 * Some bits in registers are cleared on a read, so they must
 144	 * be saved whenever the register is read, but the bits will not
 145	 * be immediately processed.
 146	 */
 147	unsigned int		lsr_break_flag;
 148	unsigned char		msr_saved_flags;
 149	char			name[20];
 150	unsigned long		port_activity;
 151	int			context_loss_cnt;
 152	u32			errata;
 153	u32			features;
 154
 155	struct gpio_desc	*rts_gpiod;
 156
 157	struct pm_qos_request	pm_qos_request;
 158	u32			latency;
 159	u32			calc_latency;
 160	struct work_struct	qos_work;
 161	bool			is_suspending;
 162};
 163
 164#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
 165
 166static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
 167
 168/* Forward declaration of functions */
 169static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
 170
 171static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
 172{
 173	offset <<= up->port.regshift;
 174	return readw(up->port.membase + offset);
 175}
 176
 177static inline void serial_out(struct uart_omap_port *up, int offset, int value)
 178{
 179	offset <<= up->port.regshift;
 180	writew(value, up->port.membase + offset);
 181}
 182
 183static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
 184{
 185	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
 186	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
 187		       UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
 188	serial_out(up, UART_FCR, 0);
 189}
 190
 191#ifdef CONFIG_PM
 192static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
 193{
 194	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
 195
 196	if (!pdata || !pdata->get_context_loss_count)
 197		return -EINVAL;
 198
 199	return pdata->get_context_loss_count(up->dev);
 200}
 201
 202/* REVISIT: Remove this when omap3 boots in device tree only mode */
 203static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
 204{
 205	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
 206
 207	if (!pdata || !pdata->enable_wakeup)
 208		return;
 209
 210	pdata->enable_wakeup(up->dev, enable);
 211}
 212#endif /* CONFIG_PM */
 213
 214/*
 215 * Calculate the absolute difference between the desired and actual baud
 216 * rate for the given mode.
 217 */
 218static inline int calculate_baud_abs_diff(struct uart_port *port,
 219				unsigned int baud, unsigned int mode)
 220{
 221	unsigned int n = port->uartclk / (mode * baud);
 222	int abs_diff;
 223
 224	if (n == 0)
 225		n = 1;
 226
 227	abs_diff = baud - (port->uartclk / (mode * n));
 228	if (abs_diff < 0)
 229		abs_diff = -abs_diff;
 230
 231	return abs_diff;
 232}
 233
 234/*
 235 * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
 236 * @port: uart port info
 237 * @baud: baudrate for which mode needs to be determined
 238 *
 239 * Returns true if baud rate is MODE16X and false if MODE13X
 240 * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
 241 * and Error Rates" determines modes not for all common baud rates.
 242 * E.g. for 1000000 baud rate mode must be 16x, but according to that
 243 * table it's determined as 13x.
 244 */
 245static bool
 246serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
 247{
 248	int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
 249	int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
 250
 251	return (abs_diff_13 >= abs_diff_16);
 252}
 253
 254/*
 255 * serial_omap_get_divisor - calculate divisor value
 256 * @port: uart port info
 257 * @baud: baudrate for which divisor needs to be calculated.
 258 */
 259static unsigned int
 260serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
 261{
 262	unsigned int mode;
 263
 264	if (!serial_omap_baud_is_mode16(port, baud))
 265		mode = 13;
 266	else
 267		mode = 16;
 268	return port->uartclk/(mode * baud);
 269}
 270
 271static void serial_omap_enable_ms(struct uart_port *port)
 272{
 273	struct uart_omap_port *up = to_uart_omap_port(port);
 274
 275	dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
 276
 277	pm_runtime_get_sync(up->dev);
 278	up->ier |= UART_IER_MSI;
 279	serial_out(up, UART_IER, up->ier);
 280	pm_runtime_mark_last_busy(up->dev);
 281	pm_runtime_put_autosuspend(up->dev);
 282}
 283
 284static void serial_omap_stop_tx(struct uart_port *port)
 285{
 286	struct uart_omap_port *up = to_uart_omap_port(port);
 287	int res;
 288
 289	pm_runtime_get_sync(up->dev);
 290
 291	/* Handle RS-485 */
 292	if (port->rs485.flags & SER_RS485_ENABLED) {
 293		if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
 294			/* THR interrupt is fired when both TX FIFO and TX
 295			 * shift register are empty. This means there's nothing
 296			 * left to transmit now, so make sure the THR interrupt
 297			 * is fired when TX FIFO is below the trigger level,
 298			 * disable THR interrupts and toggle the RS-485 GPIO
 299			 * data direction pin if needed.
 300			 */
 301			up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
 302			serial_out(up, UART_OMAP_SCR, up->scr);
 303			res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
 304				1 : 0;
 305			if (gpiod_get_value(up->rts_gpiod) != res) {
 306				if (port->rs485.delay_rts_after_send > 0)
 307					mdelay(
 308					port->rs485.delay_rts_after_send);
 309				gpiod_set_value(up->rts_gpiod, res);
 310			}
 311		} else {
 312			/* We're asked to stop, but there's still stuff in the
 313			 * UART FIFO, so make sure the THR interrupt is fired
 314			 * when both TX FIFO and TX shift register are empty.
 315			 * The next THR interrupt (if no transmission is started
 316			 * in the meantime) will indicate the end of a
 317			 * transmission. Therefore we _don't_ disable THR
 318			 * interrupts in this situation.
 319			 */
 320			up->scr |= OMAP_UART_SCR_TX_EMPTY;
 321			serial_out(up, UART_OMAP_SCR, up->scr);
 322			return;
 323		}
 324	}
 325
 326	if (up->ier & UART_IER_THRI) {
 327		up->ier &= ~UART_IER_THRI;
 328		serial_out(up, UART_IER, up->ier);
 329	}
 330
 331	if ((port->rs485.flags & SER_RS485_ENABLED) &&
 332	    !(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
 333		/*
 334		 * Empty the RX FIFO, we are not interested in anything
 335		 * received during the half-duplex transmission.
 336		 */
 337		serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_RCVR);
 338		/* Re-enable RX interrupts */
 339		up->ier |= UART_IER_RLSI | UART_IER_RDI;
 340		up->port.read_status_mask |= UART_LSR_DR;
 341		serial_out(up, UART_IER, up->ier);
 342	}
 343
 344	pm_runtime_mark_last_busy(up->dev);
 345	pm_runtime_put_autosuspend(up->dev);
 346}
 347
 348static void serial_omap_stop_rx(struct uart_port *port)
 349{
 350	struct uart_omap_port *up = to_uart_omap_port(port);
 351
 352	pm_runtime_get_sync(up->dev);
 353	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
 354	up->port.read_status_mask &= ~UART_LSR_DR;
 355	serial_out(up, UART_IER, up->ier);
 356	pm_runtime_mark_last_busy(up->dev);
 357	pm_runtime_put_autosuspend(up->dev);
 358}
 359
 360static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
 361{
 362	struct circ_buf *xmit = &up->port.state->xmit;
 363	int count;
 364
 365	if (up->port.x_char) {
 366		serial_out(up, UART_TX, up->port.x_char);
 367		up->port.icount.tx++;
 368		up->port.x_char = 0;
 369		return;
 370	}
 371	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 372		serial_omap_stop_tx(&up->port);
 373		return;
 374	}
 375	count = up->port.fifosize / 4;
 376	do {
 377		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
 378		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 379		up->port.icount.tx++;
 380		if (uart_circ_empty(xmit))
 381			break;
 382	} while (--count > 0);
 383
 384	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 385		uart_write_wakeup(&up->port);
 386
 387	if (uart_circ_empty(xmit))
 388		serial_omap_stop_tx(&up->port);
 389}
 390
 391static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
 392{
 393	if (!(up->ier & UART_IER_THRI)) {
 394		up->ier |= UART_IER_THRI;
 395		serial_out(up, UART_IER, up->ier);
 396	}
 397}
 398
 399static void serial_omap_start_tx(struct uart_port *port)
 400{
 401	struct uart_omap_port *up = to_uart_omap_port(port);
 402	int res;
 403
 404	pm_runtime_get_sync(up->dev);
 405
 406	/* Handle RS-485 */
 407	if (port->rs485.flags & SER_RS485_ENABLED) {
 408		/* Fire THR interrupts when FIFO is below trigger level */
 409		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
 410		serial_out(up, UART_OMAP_SCR, up->scr);
 411
 412		/* if rts not already enabled */
 413		res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
 414		if (gpiod_get_value(up->rts_gpiod) != res) {
 415			gpiod_set_value(up->rts_gpiod, res);
 416			if (port->rs485.delay_rts_before_send > 0)
 417				mdelay(port->rs485.delay_rts_before_send);
 418		}
 419	}
 420
 421	if ((port->rs485.flags & SER_RS485_ENABLED) &&
 422	    !(port->rs485.flags & SER_RS485_RX_DURING_TX))
 423		serial_omap_stop_rx(port);
 424
 425	serial_omap_enable_ier_thri(up);
 426	pm_runtime_mark_last_busy(up->dev);
 427	pm_runtime_put_autosuspend(up->dev);
 428}
 429
 430static void serial_omap_throttle(struct uart_port *port)
 431{
 432	struct uart_omap_port *up = to_uart_omap_port(port);
 433	unsigned long flags;
 434
 435	pm_runtime_get_sync(up->dev);
 436	spin_lock_irqsave(&up->port.lock, flags);
 437	up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
 438	serial_out(up, UART_IER, up->ier);
 439	spin_unlock_irqrestore(&up->port.lock, flags);
 440	pm_runtime_mark_last_busy(up->dev);
 441	pm_runtime_put_autosuspend(up->dev);
 442}
 443
 444static void serial_omap_unthrottle(struct uart_port *port)
 445{
 446	struct uart_omap_port *up = to_uart_omap_port(port);
 447	unsigned long flags;
 448
 449	pm_runtime_get_sync(up->dev);
 450	spin_lock_irqsave(&up->port.lock, flags);
 451	up->ier |= UART_IER_RLSI | UART_IER_RDI;
 452	serial_out(up, UART_IER, up->ier);
 453	spin_unlock_irqrestore(&up->port.lock, flags);
 454	pm_runtime_mark_last_busy(up->dev);
 455	pm_runtime_put_autosuspend(up->dev);
 456}
 457
 458static unsigned int check_modem_status(struct uart_omap_port *up)
 459{
 460	unsigned int status;
 461
 462	status = serial_in(up, UART_MSR);
 463	status |= up->msr_saved_flags;
 464	up->msr_saved_flags = 0;
 465	if ((status & UART_MSR_ANY_DELTA) == 0)
 466		return status;
 467
 468	if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
 469	    up->port.state != NULL) {
 470		if (status & UART_MSR_TERI)
 471			up->port.icount.rng++;
 472		if (status & UART_MSR_DDSR)
 473			up->port.icount.dsr++;
 474		if (status & UART_MSR_DDCD)
 475			uart_handle_dcd_change
 476				(&up->port, status & UART_MSR_DCD);
 477		if (status & UART_MSR_DCTS)
 478			uart_handle_cts_change
 479				(&up->port, status & UART_MSR_CTS);
 480		wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 481	}
 482
 483	return status;
 484}
 485
 486static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
 487{
 488	unsigned int flag;
 
 489
 490	/*
 491	 * Read one data character out to avoid stalling the receiver according
 492	 * to the table 23-246 of the omap4 TRM.
 493	 */
 494	if (likely(lsr & UART_LSR_DR))
 495		serial_in(up, UART_RX);
 496
 497	up->port.icount.rx++;
 498	flag = TTY_NORMAL;
 499
 500	if (lsr & UART_LSR_BI) {
 501		flag = TTY_BREAK;
 502		lsr &= ~(UART_LSR_FE | UART_LSR_PE);
 503		up->port.icount.brk++;
 504		/*
 505		 * We do the SysRQ and SAK checking
 506		 * here because otherwise the break
 507		 * may get masked by ignore_status_mask
 508		 * or read_status_mask.
 509		 */
 510		if (uart_handle_break(&up->port))
 511			return;
 512
 513	}
 514
 515	if (lsr & UART_LSR_PE) {
 516		flag = TTY_PARITY;
 517		up->port.icount.parity++;
 518	}
 519
 520	if (lsr & UART_LSR_FE) {
 521		flag = TTY_FRAME;
 522		up->port.icount.frame++;
 523	}
 524
 525	if (lsr & UART_LSR_OE)
 526		up->port.icount.overrun++;
 527
 528#ifdef CONFIG_SERIAL_OMAP_CONSOLE
 529	if (up->port.line == up->port.cons->index) {
 530		/* Recover the break flag from console xmit */
 531		lsr |= up->lsr_break_flag;
 532	}
 533#endif
 534	uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
 535}
 536
 537static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
 538{
 539	unsigned char ch = 0;
 540	unsigned int flag;
 541
 542	if (!(lsr & UART_LSR_DR))
 543		return;
 544
 545	ch = serial_in(up, UART_RX);
 546	flag = TTY_NORMAL;
 547	up->port.icount.rx++;
 548
 549	if (uart_handle_sysrq_char(&up->port, ch))
 550		return;
 551
 552	uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
 553}
 554
 555/**
 556 * serial_omap_irq() - This handles the interrupt from one port
 557 * @irq: uart port irq number
 558 * @dev_id: uart port info
 559 */
 560static irqreturn_t serial_omap_irq(int irq, void *dev_id)
 561{
 562	struct uart_omap_port *up = dev_id;
 563	unsigned int iir, lsr;
 564	unsigned int type;
 565	irqreturn_t ret = IRQ_NONE;
 566	int max_count = 256;
 567
 568	spin_lock(&up->port.lock);
 569	pm_runtime_get_sync(up->dev);
 570
 571	do {
 572		iir = serial_in(up, UART_IIR);
 573		if (iir & UART_IIR_NO_INT)
 574			break;
 575
 576		ret = IRQ_HANDLED;
 577		lsr = serial_in(up, UART_LSR);
 578
 579		/* extract IRQ type from IIR register */
 580		type = iir & 0x3e;
 581
 582		switch (type) {
 583		case UART_IIR_MSI:
 584			check_modem_status(up);
 585			break;
 586		case UART_IIR_THRI:
 587			transmit_chars(up, lsr);
 588			break;
 589		case UART_IIR_RX_TIMEOUT:
 
 590		case UART_IIR_RDI:
 591			serial_omap_rdi(up, lsr);
 592			break;
 593		case UART_IIR_RLSI:
 594			serial_omap_rlsi(up, lsr);
 595			break;
 596		case UART_IIR_CTS_RTS_DSR:
 597			/* simply try again */
 598			break;
 599		case UART_IIR_XOFF:
 
 600		default:
 601			break;
 602		}
 603	} while (max_count--);
 604
 605	spin_unlock(&up->port.lock);
 606
 607	tty_flip_buffer_push(&up->port.state->port);
 608
 609	pm_runtime_mark_last_busy(up->dev);
 610	pm_runtime_put_autosuspend(up->dev);
 611	up->port_activity = jiffies;
 612
 613	return ret;
 614}
 615
 616static unsigned int serial_omap_tx_empty(struct uart_port *port)
 617{
 618	struct uart_omap_port *up = to_uart_omap_port(port);
 619	unsigned long flags = 0;
 620	unsigned int ret = 0;
 621
 622	pm_runtime_get_sync(up->dev);
 623	dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
 624	spin_lock_irqsave(&up->port.lock, flags);
 625	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
 626	spin_unlock_irqrestore(&up->port.lock, flags);
 627	pm_runtime_mark_last_busy(up->dev);
 628	pm_runtime_put_autosuspend(up->dev);
 629	return ret;
 630}
 631
 632static unsigned int serial_omap_get_mctrl(struct uart_port *port)
 633{
 634	struct uart_omap_port *up = to_uart_omap_port(port);
 635	unsigned int status;
 636	unsigned int ret = 0;
 637
 638	pm_runtime_get_sync(up->dev);
 639	status = check_modem_status(up);
 640	pm_runtime_mark_last_busy(up->dev);
 641	pm_runtime_put_autosuspend(up->dev);
 642
 643	dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
 644
 645	if (status & UART_MSR_DCD)
 646		ret |= TIOCM_CAR;
 647	if (status & UART_MSR_RI)
 648		ret |= TIOCM_RNG;
 649	if (status & UART_MSR_DSR)
 650		ret |= TIOCM_DSR;
 651	if (status & UART_MSR_CTS)
 652		ret |= TIOCM_CTS;
 653	return ret;
 654}
 655
 656static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
 657{
 658	struct uart_omap_port *up = to_uart_omap_port(port);
 659	unsigned char mcr = 0, old_mcr, lcr;
 660
 661	dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
 662	if (mctrl & TIOCM_RTS)
 663		mcr |= UART_MCR_RTS;
 664	if (mctrl & TIOCM_DTR)
 665		mcr |= UART_MCR_DTR;
 666	if (mctrl & TIOCM_OUT1)
 667		mcr |= UART_MCR_OUT1;
 668	if (mctrl & TIOCM_OUT2)
 669		mcr |= UART_MCR_OUT2;
 670	if (mctrl & TIOCM_LOOP)
 671		mcr |= UART_MCR_LOOP;
 672
 673	pm_runtime_get_sync(up->dev);
 674	old_mcr = serial_in(up, UART_MCR);
 675	old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
 676		     UART_MCR_DTR | UART_MCR_RTS);
 677	up->mcr = old_mcr | mcr;
 678	serial_out(up, UART_MCR, up->mcr);
 679
 680	/* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
 681	lcr = serial_in(up, UART_LCR);
 682	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 683	if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
 684		up->efr |= UART_EFR_RTS;
 685	else
 686		up->efr &= ~UART_EFR_RTS;
 687	serial_out(up, UART_EFR, up->efr);
 688	serial_out(up, UART_LCR, lcr);
 689
 690	pm_runtime_mark_last_busy(up->dev);
 691	pm_runtime_put_autosuspend(up->dev);
 692}
 693
 694static void serial_omap_break_ctl(struct uart_port *port, int break_state)
 695{
 696	struct uart_omap_port *up = to_uart_omap_port(port);
 697	unsigned long flags = 0;
 698
 699	dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
 700	pm_runtime_get_sync(up->dev);
 701	spin_lock_irqsave(&up->port.lock, flags);
 702	if (break_state == -1)
 703		up->lcr |= UART_LCR_SBC;
 704	else
 705		up->lcr &= ~UART_LCR_SBC;
 706	serial_out(up, UART_LCR, up->lcr);
 707	spin_unlock_irqrestore(&up->port.lock, flags);
 708	pm_runtime_mark_last_busy(up->dev);
 709	pm_runtime_put_autosuspend(up->dev);
 710}
 711
 712static int serial_omap_startup(struct uart_port *port)
 713{
 714	struct uart_omap_port *up = to_uart_omap_port(port);
 715	unsigned long flags = 0;
 716	int retval;
 717
 718	/*
 719	 * Allocate the IRQ
 720	 */
 721	retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
 722				up->name, up);
 723	if (retval)
 724		return retval;
 725
 726	/* Optional wake-up IRQ */
 727	if (up->wakeirq) {
 728		retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
 729		if (retval) {
 730			free_irq(up->port.irq, up);
 731			return retval;
 732		}
 733	}
 734
 735	dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
 736
 737	pm_runtime_get_sync(up->dev);
 738	/*
 739	 * Clear the FIFO buffers and disable them.
 740	 * (they will be reenabled in set_termios())
 741	 */
 742	serial_omap_clear_fifos(up);
 743
 744	/*
 745	 * Clear the interrupt registers.
 746	 */
 747	(void) serial_in(up, UART_LSR);
 748	if (serial_in(up, UART_LSR) & UART_LSR_DR)
 749		(void) serial_in(up, UART_RX);
 750	(void) serial_in(up, UART_IIR);
 751	(void) serial_in(up, UART_MSR);
 752
 753	/*
 754	 * Now, initialize the UART
 755	 */
 756	serial_out(up, UART_LCR, UART_LCR_WLEN8);
 757	spin_lock_irqsave(&up->port.lock, flags);
 758	/*
 759	 * Most PC uarts need OUT2 raised to enable interrupts.
 760	 */
 761	up->port.mctrl |= TIOCM_OUT2;
 762	serial_omap_set_mctrl(&up->port, up->port.mctrl);
 763	spin_unlock_irqrestore(&up->port.lock, flags);
 764
 765	up->msr_saved_flags = 0;
 766	/*
 767	 * Finally, enable interrupts. Note: Modem status interrupts
 768	 * are set via set_termios(), which will be occurring imminently
 769	 * anyway, so we don't enable them here.
 770	 */
 771	up->ier = UART_IER_RLSI | UART_IER_RDI;
 772	serial_out(up, UART_IER, up->ier);
 773
 774	/* Enable module level wake up */
 775	up->wer = OMAP_UART_WER_MOD_WKUP;
 776	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
 777		up->wer |= OMAP_UART_TX_WAKEUP_EN;
 778
 779	serial_out(up, UART_OMAP_WER, up->wer);
 780
 781	pm_runtime_mark_last_busy(up->dev);
 782	pm_runtime_put_autosuspend(up->dev);
 783	up->port_activity = jiffies;
 784	return 0;
 785}
 786
 787static void serial_omap_shutdown(struct uart_port *port)
 788{
 789	struct uart_omap_port *up = to_uart_omap_port(port);
 790	unsigned long flags = 0;
 791
 792	dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
 793
 794	pm_runtime_get_sync(up->dev);
 795	/*
 796	 * Disable interrupts from this port
 797	 */
 798	up->ier = 0;
 799	serial_out(up, UART_IER, 0);
 800
 801	spin_lock_irqsave(&up->port.lock, flags);
 802	up->port.mctrl &= ~TIOCM_OUT2;
 803	serial_omap_set_mctrl(&up->port, up->port.mctrl);
 804	spin_unlock_irqrestore(&up->port.lock, flags);
 805
 806	/*
 807	 * Disable break condition and FIFOs
 808	 */
 809	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
 810	serial_omap_clear_fifos(up);
 811
 812	/*
 813	 * Read data port to reset things, and then free the irq
 814	 */
 815	if (serial_in(up, UART_LSR) & UART_LSR_DR)
 816		(void) serial_in(up, UART_RX);
 817
 818	pm_runtime_mark_last_busy(up->dev);
 819	pm_runtime_put_autosuspend(up->dev);
 820	free_irq(up->port.irq, up);
 821	dev_pm_clear_wake_irq(up->dev);
 822}
 823
 824static void serial_omap_uart_qos_work(struct work_struct *work)
 825{
 826	struct uart_omap_port *up = container_of(work, struct uart_omap_port,
 827						qos_work);
 828
 829	cpu_latency_qos_update_request(&up->pm_qos_request, up->latency);
 830}
 831
 832static void
 833serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
 834			struct ktermios *old)
 835{
 836	struct uart_omap_port *up = to_uart_omap_port(port);
 837	unsigned char cval = 0;
 838	unsigned long flags = 0;
 839	unsigned int baud, quot;
 840
 841	switch (termios->c_cflag & CSIZE) {
 842	case CS5:
 843		cval = UART_LCR_WLEN5;
 844		break;
 845	case CS6:
 846		cval = UART_LCR_WLEN6;
 847		break;
 848	case CS7:
 849		cval = UART_LCR_WLEN7;
 850		break;
 851	default:
 852	case CS8:
 853		cval = UART_LCR_WLEN8;
 854		break;
 855	}
 856
 857	if (termios->c_cflag & CSTOPB)
 858		cval |= UART_LCR_STOP;
 859	if (termios->c_cflag & PARENB)
 860		cval |= UART_LCR_PARITY;
 861	if (!(termios->c_cflag & PARODD))
 862		cval |= UART_LCR_EPAR;
 863	if (termios->c_cflag & CMSPAR)
 864		cval |= UART_LCR_SPAR;
 865
 866	/*
 867	 * Ask the core to calculate the divisor for us.
 868	 */
 869
 870	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
 871	quot = serial_omap_get_divisor(port, baud);
 872
 873	/* calculate wakeup latency constraint */
 874	up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
 875	up->latency = up->calc_latency;
 876	schedule_work(&up->qos_work);
 877
 878	up->dll = quot & 0xff;
 879	up->dlh = quot >> 8;
 880	up->mdr1 = UART_OMAP_MDR1_DISABLE;
 881
 882	up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
 883			UART_FCR_ENABLE_FIFO;
 884
 885	/*
 886	 * Ok, we're now changing the port state. Do it with
 887	 * interrupts disabled.
 888	 */
 889	pm_runtime_get_sync(up->dev);
 890	spin_lock_irqsave(&up->port.lock, flags);
 891
 892	/*
 893	 * Update the per-port timeout.
 894	 */
 895	uart_update_timeout(port, termios->c_cflag, baud);
 896
 897	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
 898	if (termios->c_iflag & INPCK)
 899		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 900	if (termios->c_iflag & (BRKINT | PARMRK))
 901		up->port.read_status_mask |= UART_LSR_BI;
 902
 903	/*
 904	 * Characters to ignore
 905	 */
 906	up->port.ignore_status_mask = 0;
 907	if (termios->c_iflag & IGNPAR)
 908		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 909	if (termios->c_iflag & IGNBRK) {
 910		up->port.ignore_status_mask |= UART_LSR_BI;
 911		/*
 912		 * If we're ignoring parity and break indicators,
 913		 * ignore overruns too (for real raw support).
 914		 */
 915		if (termios->c_iflag & IGNPAR)
 916			up->port.ignore_status_mask |= UART_LSR_OE;
 917	}
 918
 919	/*
 920	 * ignore all characters if CREAD is not set
 921	 */
 922	if ((termios->c_cflag & CREAD) == 0)
 923		up->port.ignore_status_mask |= UART_LSR_DR;
 924
 925	/*
 926	 * Modem status interrupts
 927	 */
 928	up->ier &= ~UART_IER_MSI;
 929	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
 930		up->ier |= UART_IER_MSI;
 931	serial_out(up, UART_IER, up->ier);
 932	serial_out(up, UART_LCR, cval);		/* reset DLAB */
 933	up->lcr = cval;
 934	up->scr = 0;
 935
 936	/* FIFOs and DMA Settings */
 937
 938	/* FCR can be changed only when the
 939	 * baud clock is not running
 940	 * DLL_REG and DLH_REG set to 0.
 941	 */
 942	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 943	serial_out(up, UART_DLL, 0);
 944	serial_out(up, UART_DLM, 0);
 945	serial_out(up, UART_LCR, 0);
 946
 947	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 948
 949	up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
 950	up->efr &= ~UART_EFR_SCD;
 951	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 952
 953	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 954	up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
 955	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
 956	/* FIFO ENABLE, DMA MODE */
 957
 958	up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
 959	/*
 960	 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
 961	 * sets Enables the granularity of 1 for TRIGGER RX
 962	 * level. Along with setting RX FIFO trigger level
 963	 * to 1 (as noted below, 16 characters) and TLR[3:0]
 964	 * to zero this will result RX FIFO threshold level
 965	 * to 1 character, instead of 16 as noted in comment
 966	 * below.
 967	 */
 968
 969	/* Set receive FIFO threshold to 16 characters and
 970	 * transmit FIFO threshold to 32 spaces
 971	 */
 972	up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
 973	up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
 974	up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
 975		UART_FCR_ENABLE_FIFO;
 976
 977	serial_out(up, UART_FCR, up->fcr);
 978	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 979
 980	serial_out(up, UART_OMAP_SCR, up->scr);
 981
 982	/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
 983	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 984	serial_out(up, UART_MCR, up->mcr);
 985	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 986	serial_out(up, UART_EFR, up->efr);
 987	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
 988
 989	/* Protocol, Baud Rate, and Interrupt Settings */
 990
 991	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
 992		serial_omap_mdr1_errataset(up, up->mdr1);
 993	else
 994		serial_out(up, UART_OMAP_MDR1, up->mdr1);
 995
 996	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
 997	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
 998
 999	serial_out(up, UART_LCR, 0);
1000	serial_out(up, UART_IER, 0);
1001	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1002
1003	serial_out(up, UART_DLL, up->dll);	/* LS of divisor */
1004	serial_out(up, UART_DLM, up->dlh);	/* MS of divisor */
1005
1006	serial_out(up, UART_LCR, 0);
1007	serial_out(up, UART_IER, up->ier);
1008	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1009
1010	serial_out(up, UART_EFR, up->efr);
1011	serial_out(up, UART_LCR, cval);
1012
1013	if (!serial_omap_baud_is_mode16(port, baud))
1014		up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1015	else
1016		up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1017
1018	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1019		serial_omap_mdr1_errataset(up, up->mdr1);
1020	else
1021		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1022
1023	/* Configure flow control */
1024	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1025
1026	/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1027	serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1028	serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1029
1030	/* Enable access to TCR/TLR */
1031	serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1032	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1033	serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1034
1035	serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1036
1037	up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
1038
1039	if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1040		/* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
1041		up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
1042		up->efr |= UART_EFR_CTS;
1043	} else {
1044		/* Disable AUTORTS and AUTOCTS */
1045		up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1046	}
1047
1048	if (up->port.flags & UPF_SOFT_FLOW) {
1049		/* clear SW control mode bits */
1050		up->efr &= OMAP_UART_SW_CLR;
1051
1052		/*
1053		 * IXON Flag:
1054		 * Enable XON/XOFF flow control on input.
1055		 * Receiver compares XON1, XOFF1.
1056		 */
1057		if (termios->c_iflag & IXON)
1058			up->efr |= OMAP_UART_SW_RX;
1059
1060		/*
1061		 * IXOFF Flag:
1062		 * Enable XON/XOFF flow control on output.
1063		 * Transmit XON1, XOFF1
1064		 */
1065		if (termios->c_iflag & IXOFF) {
1066			up->port.status |= UPSTAT_AUTOXOFF;
1067			up->efr |= OMAP_UART_SW_TX;
1068		}
1069
1070		/*
1071		 * IXANY Flag:
1072		 * Enable any character to restart output.
1073		 * Operation resumes after receiving any
1074		 * character after recognition of the XOFF character
1075		 */
1076		if (termios->c_iflag & IXANY)
1077			up->mcr |= UART_MCR_XONANY;
1078		else
1079			up->mcr &= ~UART_MCR_XONANY;
1080	}
1081	serial_out(up, UART_MCR, up->mcr);
1082	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1083	serial_out(up, UART_EFR, up->efr);
1084	serial_out(up, UART_LCR, up->lcr);
1085
1086	serial_omap_set_mctrl(&up->port, up->port.mctrl);
1087
1088	spin_unlock_irqrestore(&up->port.lock, flags);
1089	pm_runtime_mark_last_busy(up->dev);
1090	pm_runtime_put_autosuspend(up->dev);
1091	dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1092}
1093
1094static void
1095serial_omap_pm(struct uart_port *port, unsigned int state,
1096	       unsigned int oldstate)
1097{
1098	struct uart_omap_port *up = to_uart_omap_port(port);
1099	unsigned char efr;
1100
1101	dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1102
1103	pm_runtime_get_sync(up->dev);
1104	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1105	efr = serial_in(up, UART_EFR);
1106	serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1107	serial_out(up, UART_LCR, 0);
1108
1109	serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1110	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1111	serial_out(up, UART_EFR, efr);
1112	serial_out(up, UART_LCR, 0);
1113
1114	pm_runtime_mark_last_busy(up->dev);
1115	pm_runtime_put_autosuspend(up->dev);
1116}
1117
1118static void serial_omap_release_port(struct uart_port *port)
1119{
1120	dev_dbg(port->dev, "serial_omap_release_port+\n");
1121}
1122
1123static int serial_omap_request_port(struct uart_port *port)
1124{
1125	dev_dbg(port->dev, "serial_omap_request_port+\n");
1126	return 0;
1127}
1128
1129static void serial_omap_config_port(struct uart_port *port, int flags)
1130{
1131	struct uart_omap_port *up = to_uart_omap_port(port);
1132
1133	dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1134							up->port.line);
1135	up->port.type = PORT_OMAP;
1136	up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1137}
1138
1139static int
1140serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1141{
1142	/* we don't want the core code to modify any port params */
1143	dev_dbg(port->dev, "serial_omap_verify_port+\n");
1144	return -EINVAL;
1145}
1146
1147static const char *
1148serial_omap_type(struct uart_port *port)
1149{
1150	struct uart_omap_port *up = to_uart_omap_port(port);
1151
1152	dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1153	return up->name;
1154}
1155
1156#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1157
1158static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
1159{
1160	unsigned int status, tmout = 10000;
1161
1162	/* Wait up to 10ms for the character(s) to be sent. */
1163	do {
1164		status = serial_in(up, UART_LSR);
1165
1166		if (status & UART_LSR_BI)
1167			up->lsr_break_flag = UART_LSR_BI;
1168
1169		if (--tmout == 0)
1170			break;
1171		udelay(1);
1172	} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1173
1174	/* Wait up to 1s for flow control if necessary */
1175	if (up->port.flags & UPF_CONS_FLOW) {
1176		tmout = 1000000;
1177		for (tmout = 1000000; tmout; tmout--) {
1178			unsigned int msr = serial_in(up, UART_MSR);
1179
1180			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1181			if (msr & UART_MSR_CTS)
1182				break;
1183
1184			udelay(1);
1185		}
1186	}
1187}
1188
1189#ifdef CONFIG_CONSOLE_POLL
1190
1191static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1192{
1193	struct uart_omap_port *up = to_uart_omap_port(port);
1194
1195	pm_runtime_get_sync(up->dev);
1196	wait_for_xmitr(up);
1197	serial_out(up, UART_TX, ch);
1198	pm_runtime_mark_last_busy(up->dev);
1199	pm_runtime_put_autosuspend(up->dev);
1200}
1201
1202static int serial_omap_poll_get_char(struct uart_port *port)
1203{
1204	struct uart_omap_port *up = to_uart_omap_port(port);
1205	unsigned int status;
1206
1207	pm_runtime_get_sync(up->dev);
1208	status = serial_in(up, UART_LSR);
1209	if (!(status & UART_LSR_DR)) {
1210		status = NO_POLL_CHAR;
1211		goto out;
1212	}
1213
1214	status = serial_in(up, UART_RX);
1215
1216out:
1217	pm_runtime_mark_last_busy(up->dev);
1218	pm_runtime_put_autosuspend(up->dev);
1219
1220	return status;
1221}
1222
1223#endif /* CONFIG_CONSOLE_POLL */
1224
1225#ifdef CONFIG_SERIAL_OMAP_CONSOLE
1226
1227#ifdef CONFIG_SERIAL_EARLYCON
1228static unsigned int omap_serial_early_in(struct uart_port *port, int offset)
1229{
1230	offset <<= port->regshift;
1231	return readw(port->membase + offset);
1232}
1233
1234static void omap_serial_early_out(struct uart_port *port, int offset,
1235				  int value)
1236{
1237	offset <<= port->regshift;
1238	writew(value, port->membase + offset);
1239}
1240
1241static void omap_serial_early_putc(struct uart_port *port, int c)
1242{
1243	unsigned int status;
1244
1245	for (;;) {
1246		status = omap_serial_early_in(port, UART_LSR);
1247		if ((status & BOTH_EMPTY) == BOTH_EMPTY)
1248			break;
1249		cpu_relax();
1250	}
1251	omap_serial_early_out(port, UART_TX, c);
1252}
1253
1254static void early_omap_serial_write(struct console *console, const char *s,
1255				    unsigned int count)
1256{
1257	struct earlycon_device *device = console->data;
1258	struct uart_port *port = &device->port;
1259
1260	uart_console_write(port, s, count, omap_serial_early_putc);
1261}
1262
1263static int __init early_omap_serial_setup(struct earlycon_device *device,
1264					  const char *options)
1265{
1266	struct uart_port *port = &device->port;
1267
1268	if (!(device->port.membase || device->port.iobase))
1269		return -ENODEV;
1270
1271	port->regshift = 2;
1272	device->con->write = early_omap_serial_write;
1273	return 0;
1274}
1275
1276OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup);
1277OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup);
1278OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup);
1279#endif /* CONFIG_SERIAL_EARLYCON */
1280
1281static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1282
1283static struct uart_driver serial_omap_reg;
1284
1285static void serial_omap_console_putchar(struct uart_port *port, int ch)
1286{
1287	struct uart_omap_port *up = to_uart_omap_port(port);
1288
1289	wait_for_xmitr(up);
1290	serial_out(up, UART_TX, ch);
1291}
1292
1293static void
1294serial_omap_console_write(struct console *co, const char *s,
1295		unsigned int count)
1296{
1297	struct uart_omap_port *up = serial_omap_console_ports[co->index];
1298	unsigned long flags;
1299	unsigned int ier;
1300	int locked = 1;
1301
1302	pm_runtime_get_sync(up->dev);
1303
1304	local_irq_save(flags);
1305	if (up->port.sysrq)
1306		locked = 0;
1307	else if (oops_in_progress)
1308		locked = spin_trylock(&up->port.lock);
1309	else
1310		spin_lock(&up->port.lock);
1311
1312	/*
1313	 * First save the IER then disable the interrupts
1314	 */
1315	ier = serial_in(up, UART_IER);
1316	serial_out(up, UART_IER, 0);
1317
1318	uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1319
1320	/*
1321	 * Finally, wait for transmitter to become empty
1322	 * and restore the IER
1323	 */
1324	wait_for_xmitr(up);
1325	serial_out(up, UART_IER, ier);
1326	/*
1327	 * The receive handling will happen properly because the
1328	 * receive ready bit will still be set; it is not cleared
1329	 * on read.  However, modem control will not, we must
1330	 * call it if we have saved something in the saved flags
1331	 * while processing with interrupts off.
1332	 */
1333	if (up->msr_saved_flags)
1334		check_modem_status(up);
1335
1336	pm_runtime_mark_last_busy(up->dev);
1337	pm_runtime_put_autosuspend(up->dev);
1338	if (locked)
1339		spin_unlock(&up->port.lock);
1340	local_irq_restore(flags);
1341}
1342
1343static int __init
1344serial_omap_console_setup(struct console *co, char *options)
1345{
1346	struct uart_omap_port *up;
1347	int baud = 115200;
1348	int bits = 8;
1349	int parity = 'n';
1350	int flow = 'n';
1351
1352	if (serial_omap_console_ports[co->index] == NULL)
1353		return -ENODEV;
1354	up = serial_omap_console_ports[co->index];
1355
1356	if (options)
1357		uart_parse_options(options, &baud, &parity, &bits, &flow);
1358
1359	return uart_set_options(&up->port, co, baud, parity, bits, flow);
1360}
1361
1362static struct console serial_omap_console = {
1363	.name		= OMAP_SERIAL_NAME,
1364	.write		= serial_omap_console_write,
1365	.device		= uart_console_device,
1366	.setup		= serial_omap_console_setup,
1367	.flags		= CON_PRINTBUFFER,
1368	.index		= -1,
1369	.data		= &serial_omap_reg,
1370};
1371
1372static void serial_omap_add_console_port(struct uart_omap_port *up)
1373{
1374	serial_omap_console_ports[up->port.line] = up;
1375}
1376
1377#define OMAP_CONSOLE	(&serial_omap_console)
1378
1379#else
1380
1381#define OMAP_CONSOLE	NULL
1382
1383static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1384{}
1385
1386#endif
1387
1388/* Enable or disable the rs485 support */
1389static int
1390serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
1391{
1392	struct uart_omap_port *up = to_uart_omap_port(port);
1393	unsigned int mode;
1394	int val;
1395
1396	pm_runtime_get_sync(up->dev);
1397
1398	/* Disable interrupts from this port */
1399	mode = up->ier;
1400	up->ier = 0;
1401	serial_out(up, UART_IER, 0);
1402
1403	/* Clamp the delays to [0, 100ms] */
1404	rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
1405	rs485->delay_rts_after_send  = min(rs485->delay_rts_after_send, 100U);
1406
1407	/* store new config */
1408	port->rs485 = *rs485;
1409
1410	/*
1411	 * Just as a precaution, only allow rs485
1412	 * to be enabled if the gpio pin is valid
1413	 */
1414	if (up->rts_gpiod) {
1415		/* enable / disable rts */
1416		val = (port->rs485.flags & SER_RS485_ENABLED) ?
1417			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1418		val = (port->rs485.flags & val) ? 1 : 0;
1419		gpiod_set_value(up->rts_gpiod, val);
1420	} else
1421		port->rs485.flags &= ~SER_RS485_ENABLED;
1422
1423	/* Enable interrupts */
1424	up->ier = mode;
1425	serial_out(up, UART_IER, up->ier);
1426
1427	/* If RS-485 is disabled, make sure the THR interrupt is fired when
1428	 * TX FIFO is below the trigger level.
1429	 */
1430	if (!(port->rs485.flags & SER_RS485_ENABLED) &&
1431	    (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1432		up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1433		serial_out(up, UART_OMAP_SCR, up->scr);
1434	}
1435
1436	pm_runtime_mark_last_busy(up->dev);
1437	pm_runtime_put_autosuspend(up->dev);
1438
1439	return 0;
1440}
1441
1442static const struct uart_ops serial_omap_pops = {
1443	.tx_empty	= serial_omap_tx_empty,
1444	.set_mctrl	= serial_omap_set_mctrl,
1445	.get_mctrl	= serial_omap_get_mctrl,
1446	.stop_tx	= serial_omap_stop_tx,
1447	.start_tx	= serial_omap_start_tx,
1448	.throttle	= serial_omap_throttle,
1449	.unthrottle	= serial_omap_unthrottle,
1450	.stop_rx	= serial_omap_stop_rx,
1451	.enable_ms	= serial_omap_enable_ms,
1452	.break_ctl	= serial_omap_break_ctl,
1453	.startup	= serial_omap_startup,
1454	.shutdown	= serial_omap_shutdown,
1455	.set_termios	= serial_omap_set_termios,
1456	.pm		= serial_omap_pm,
1457	.type		= serial_omap_type,
1458	.release_port	= serial_omap_release_port,
1459	.request_port	= serial_omap_request_port,
1460	.config_port	= serial_omap_config_port,
1461	.verify_port	= serial_omap_verify_port,
1462#ifdef CONFIG_CONSOLE_POLL
1463	.poll_put_char  = serial_omap_poll_put_char,
1464	.poll_get_char  = serial_omap_poll_get_char,
1465#endif
1466};
1467
1468static struct uart_driver serial_omap_reg = {
1469	.owner		= THIS_MODULE,
1470	.driver_name	= "OMAP-SERIAL",
1471	.dev_name	= OMAP_SERIAL_NAME,
1472	.nr		= OMAP_MAX_HSUART_PORTS,
1473	.cons		= OMAP_CONSOLE,
1474};
1475
1476#ifdef CONFIG_PM_SLEEP
1477static int serial_omap_prepare(struct device *dev)
1478{
1479	struct uart_omap_port *up = dev_get_drvdata(dev);
1480
1481	up->is_suspending = true;
1482
1483	return 0;
1484}
1485
1486static void serial_omap_complete(struct device *dev)
1487{
1488	struct uart_omap_port *up = dev_get_drvdata(dev);
1489
1490	up->is_suspending = false;
1491}
1492
1493static int serial_omap_suspend(struct device *dev)
1494{
1495	struct uart_omap_port *up = dev_get_drvdata(dev);
1496
1497	uart_suspend_port(&serial_omap_reg, &up->port);
1498	flush_work(&up->qos_work);
1499
1500	if (device_may_wakeup(dev))
1501		serial_omap_enable_wakeup(up, true);
1502	else
1503		serial_omap_enable_wakeup(up, false);
1504
1505	return 0;
1506}
1507
1508static int serial_omap_resume(struct device *dev)
1509{
1510	struct uart_omap_port *up = dev_get_drvdata(dev);
1511
1512	if (device_may_wakeup(dev))
1513		serial_omap_enable_wakeup(up, false);
1514
1515	uart_resume_port(&serial_omap_reg, &up->port);
1516
1517	return 0;
1518}
1519#else
1520#define serial_omap_prepare NULL
1521#define serial_omap_complete NULL
1522#endif /* CONFIG_PM_SLEEP */
1523
1524static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1525{
1526	u32 mvr, scheme;
1527	u16 revision, major, minor;
1528
1529	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1530
1531	/* Check revision register scheme */
1532	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1533
1534	switch (scheme) {
1535	case 0: /* Legacy Scheme: OMAP2/3 */
1536		/* MINOR_REV[0:4], MAJOR_REV[4:7] */
1537		major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1538					OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1539		minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1540		break;
1541	case 1:
1542		/* New Scheme: OMAP4+ */
1543		/* MINOR_REV[0:5], MAJOR_REV[8:10] */
1544		major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1545					OMAP_UART_MVR_MAJ_SHIFT;
1546		minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1547		break;
1548	default:
1549		dev_warn(up->dev,
1550			"Unknown %s revision, defaulting to highest\n",
1551			up->name);
1552		/* highest possible revision */
1553		major = 0xff;
1554		minor = 0xff;
1555	}
1556
1557	/* normalize revision for the driver */
1558	revision = UART_BUILD_REVISION(major, minor);
1559
1560	switch (revision) {
1561	case OMAP_UART_REV_46:
1562		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1563				UART_ERRATA_i291_DMA_FORCEIDLE);
1564		break;
1565	case OMAP_UART_REV_52:
1566		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1567				UART_ERRATA_i291_DMA_FORCEIDLE);
1568		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1569		break;
1570	case OMAP_UART_REV_63:
1571		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1572		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1573		break;
1574	default:
1575		break;
1576	}
1577}
1578
1579static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1580{
1581	struct omap_uart_port_info *omap_up_info;
1582
1583	omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1584	if (!omap_up_info)
1585		return NULL; /* out of memory */
1586
1587	of_property_read_u32(dev->of_node, "clock-frequency",
1588					 &omap_up_info->uartclk);
1589
1590	omap_up_info->flags = UPF_BOOT_AUTOCONF;
1591
1592	return omap_up_info;
1593}
1594
1595static int serial_omap_probe_rs485(struct uart_omap_port *up,
1596				   struct device *dev)
1597{
1598	struct serial_rs485 *rs485conf = &up->port.rs485;
1599	struct device_node *np = dev->of_node;
1600	enum gpiod_flags gflags;
1601	int ret;
1602
1603	rs485conf->flags = 0;
1604	up->rts_gpiod = NULL;
1605
1606	if (!np)
1607		return 0;
1608
1609	ret = uart_get_rs485_mode(&up->port);
1610	if (ret)
1611		return ret;
1612
1613	if (of_property_read_bool(np, "rs485-rts-active-high")) {
1614		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1615		rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND;
1616	} else {
1617		rs485conf->flags &= ~SER_RS485_RTS_ON_SEND;
1618		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1619	}
1620
1621	/* check for tx enable gpio */
1622	gflags = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ?
1623		GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
1624	up->rts_gpiod = devm_gpiod_get_optional(dev, "rts", gflags);
1625	if (IS_ERR(up->rts_gpiod)) {
1626		ret = PTR_ERR(up->rts_gpiod);
1627	        if (ret == -EPROBE_DEFER)
 
 
1628			return ret;
1629		/*
1630		 * FIXME: the code historically ignored any other error than
1631		 * -EPROBE_DEFER and just went on without GPIO.
1632		 */
1633		up->rts_gpiod = NULL;
1634	} else {
1635		gpiod_set_consumer_name(up->rts_gpiod, "omap-serial");
1636	}
1637
1638	return 0;
1639}
1640
1641static int serial_omap_probe(struct platform_device *pdev)
1642{
1643	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1644	struct uart_omap_port *up;
1645	struct resource *mem;
1646	void __iomem *base;
1647	int uartirq = 0;
1648	int wakeirq = 0;
1649	int ret;
1650
1651	/* The optional wakeirq may be specified in the board dts file */
1652	if (pdev->dev.of_node) {
1653		uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1654		if (!uartirq)
1655			return -EPROBE_DEFER;
1656		wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1657		omap_up_info = of_get_uart_port_info(&pdev->dev);
1658		pdev->dev.platform_data = omap_up_info;
1659	} else {
1660		uartirq = platform_get_irq(pdev, 0);
1661		if (uartirq < 0)
1662			return -EPROBE_DEFER;
1663	}
1664
1665	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1666	if (!up)
1667		return -ENOMEM;
1668
1669	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1670	base = devm_ioremap_resource(&pdev->dev, mem);
1671	if (IS_ERR(base))
1672		return PTR_ERR(base);
1673
1674	up->dev = &pdev->dev;
1675	up->port.dev = &pdev->dev;
1676	up->port.type = PORT_OMAP;
1677	up->port.iotype = UPIO_MEM;
1678	up->port.irq = uartirq;
1679	up->port.regshift = 2;
1680	up->port.fifosize = 64;
1681	up->port.ops = &serial_omap_pops;
1682	up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_OMAP_CONSOLE);
1683
1684	if (pdev->dev.of_node)
1685		ret = of_alias_get_id(pdev->dev.of_node, "serial");
1686	else
1687		ret = pdev->id;
1688
1689	if (ret < 0) {
1690		dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1691			ret);
1692		goto err_port_line;
1693	}
1694	up->port.line = ret;
1695
1696	if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1697		dev_err(&pdev->dev, "uart ID %d >  MAX %d.\n", up->port.line,
1698			OMAP_MAX_HSUART_PORTS);
1699		ret = -ENXIO;
1700		goto err_port_line;
1701	}
1702
1703	up->wakeirq = wakeirq;
1704	if (!up->wakeirq)
1705		dev_info(up->port.dev, "no wakeirq for uart%d\n",
1706			 up->port.line);
1707
1708	ret = serial_omap_probe_rs485(up, &pdev->dev);
1709	if (ret < 0)
1710		goto err_rs485;
1711
1712	sprintf(up->name, "OMAP UART%d", up->port.line);
1713	up->port.mapbase = mem->start;
1714	up->port.membase = base;
1715	up->port.flags = omap_up_info->flags;
1716	up->port.uartclk = omap_up_info->uartclk;
1717	up->port.rs485_config = serial_omap_config_rs485;
1718	if (!up->port.uartclk) {
1719		up->port.uartclk = DEFAULT_CLK_SPEED;
1720		dev_warn(&pdev->dev,
1721			 "No clock speed specified: using default: %d\n",
1722			 DEFAULT_CLK_SPEED);
1723	}
1724
1725	up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1726	up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1727	cpu_latency_qos_add_request(&up->pm_qos_request, up->latency);
 
1728	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1729
1730	platform_set_drvdata(pdev, up);
1731	if (omap_up_info->autosuspend_timeout == 0)
1732		omap_up_info->autosuspend_timeout = -1;
1733
1734	device_init_wakeup(up->dev, true);
1735	pm_runtime_use_autosuspend(&pdev->dev);
1736	pm_runtime_set_autosuspend_delay(&pdev->dev,
1737			omap_up_info->autosuspend_timeout);
1738
1739	pm_runtime_irq_safe(&pdev->dev);
1740	pm_runtime_enable(&pdev->dev);
1741
1742	pm_runtime_get_sync(&pdev->dev);
1743
1744	omap_serial_fill_features_erratas(up);
1745
1746	ui[up->port.line] = up;
1747	serial_omap_add_console_port(up);
1748
1749	ret = uart_add_one_port(&serial_omap_reg, &up->port);
1750	if (ret != 0)
1751		goto err_add_port;
1752
1753	pm_runtime_mark_last_busy(up->dev);
1754	pm_runtime_put_autosuspend(up->dev);
1755	return 0;
1756
1757err_add_port:
1758	pm_runtime_dont_use_autosuspend(&pdev->dev);
1759	pm_runtime_put_sync(&pdev->dev);
1760	pm_runtime_disable(&pdev->dev);
1761	cpu_latency_qos_remove_request(&up->pm_qos_request);
1762	device_init_wakeup(up->dev, false);
1763err_rs485:
1764err_port_line:
1765	return ret;
1766}
1767
1768static int serial_omap_remove(struct platform_device *dev)
1769{
1770	struct uart_omap_port *up = platform_get_drvdata(dev);
1771
1772	pm_runtime_get_sync(up->dev);
1773
1774	uart_remove_one_port(&serial_omap_reg, &up->port);
1775
1776	pm_runtime_dont_use_autosuspend(up->dev);
1777	pm_runtime_put_sync(up->dev);
1778	pm_runtime_disable(up->dev);
1779	cpu_latency_qos_remove_request(&up->pm_qos_request);
1780	device_init_wakeup(&dev->dev, false);
1781
1782	return 0;
1783}
1784
1785/*
1786 * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1787 * The access to uart register after MDR1 Access
1788 * causes UART to corrupt data.
1789 *
1790 * Need a delay =
1791 * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1792 * give 10 times as much
1793 */
1794static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1795{
1796	u8 timeout = 255;
1797
1798	serial_out(up, UART_OMAP_MDR1, mdr1);
1799	udelay(2);
1800	serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1801			UART_FCR_CLEAR_RCVR);
1802	/*
1803	 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1804	 * TX_FIFO_E bit is 1.
1805	 */
1806	while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1807				(UART_LSR_THRE | UART_LSR_DR))) {
1808		timeout--;
1809		if (!timeout) {
1810			/* Should *never* happen. we warn and carry on */
1811			dev_crit(up->dev, "Errata i202: timedout %x\n",
1812						serial_in(up, UART_LSR));
1813			break;
1814		}
1815		udelay(1);
1816	}
1817}
1818
1819#ifdef CONFIG_PM
1820static void serial_omap_restore_context(struct uart_omap_port *up)
1821{
1822	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1823		serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1824	else
1825		serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1826
1827	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1828	serial_out(up, UART_EFR, UART_EFR_ECB);
1829	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1830	serial_out(up, UART_IER, 0x0);
1831	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1832	serial_out(up, UART_DLL, up->dll);
1833	serial_out(up, UART_DLM, up->dlh);
1834	serial_out(up, UART_LCR, 0x0); /* Operational mode */
1835	serial_out(up, UART_IER, up->ier);
1836	serial_out(up, UART_FCR, up->fcr);
1837	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1838	serial_out(up, UART_MCR, up->mcr);
1839	serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1840	serial_out(up, UART_OMAP_SCR, up->scr);
1841	serial_out(up, UART_EFR, up->efr);
1842	serial_out(up, UART_LCR, up->lcr);
1843	if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1844		serial_omap_mdr1_errataset(up, up->mdr1);
1845	else
1846		serial_out(up, UART_OMAP_MDR1, up->mdr1);
1847	serial_out(up, UART_OMAP_WER, up->wer);
1848}
1849
1850static int serial_omap_runtime_suspend(struct device *dev)
1851{
1852	struct uart_omap_port *up = dev_get_drvdata(dev);
1853
1854	if (!up)
1855		return -EINVAL;
1856
1857	/*
1858	* When using 'no_console_suspend', the console UART must not be
1859	* suspended. Since driver suspend is managed by runtime suspend,
1860	* preventing runtime suspend (by returning error) will keep device
1861	* active during suspend.
1862	*/
1863	if (up->is_suspending && !console_suspend_enabled &&
1864	    uart_console(&up->port))
1865		return -EBUSY;
1866
1867	up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1868
1869	serial_omap_enable_wakeup(up, true);
1870
1871	up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1872	schedule_work(&up->qos_work);
1873
1874	return 0;
1875}
1876
1877static int serial_omap_runtime_resume(struct device *dev)
1878{
1879	struct uart_omap_port *up = dev_get_drvdata(dev);
1880
1881	int loss_cnt = serial_omap_get_context_loss_count(up);
1882
1883	serial_omap_enable_wakeup(up, false);
1884
1885	if (loss_cnt < 0) {
1886		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1887			loss_cnt);
1888		serial_omap_restore_context(up);
1889	} else if (up->context_loss_cnt != loss_cnt) {
1890		serial_omap_restore_context(up);
1891	}
1892	up->latency = up->calc_latency;
1893	schedule_work(&up->qos_work);
1894
1895	return 0;
1896}
1897#endif
1898
1899static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1900	SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1901	SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1902				serial_omap_runtime_resume, NULL)
1903	.prepare        = serial_omap_prepare,
1904	.complete       = serial_omap_complete,
1905};
1906
1907#if defined(CONFIG_OF)
1908static const struct of_device_id omap_serial_of_match[] = {
1909	{ .compatible = "ti,omap2-uart" },
1910	{ .compatible = "ti,omap3-uart" },
1911	{ .compatible = "ti,omap4-uart" },
1912	{},
1913};
1914MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1915#endif
1916
1917static struct platform_driver serial_omap_driver = {
1918	.probe          = serial_omap_probe,
1919	.remove         = serial_omap_remove,
1920	.driver		= {
1921		.name	= OMAP_SERIAL_DRIVER_NAME,
1922		.pm	= &serial_omap_dev_pm_ops,
1923		.of_match_table = of_match_ptr(omap_serial_of_match),
1924	},
1925};
1926
1927static int __init serial_omap_init(void)
1928{
1929	int ret;
1930
1931	ret = uart_register_driver(&serial_omap_reg);
1932	if (ret != 0)
1933		return ret;
1934	ret = platform_driver_register(&serial_omap_driver);
1935	if (ret != 0)
1936		uart_unregister_driver(&serial_omap_reg);
1937	return ret;
1938}
1939
1940static void __exit serial_omap_exit(void)
1941{
1942	platform_driver_unregister(&serial_omap_driver);
1943	uart_unregister_driver(&serial_omap_reg);
1944}
1945
1946module_init(serial_omap_init);
1947module_exit(serial_omap_exit);
1948
1949MODULE_DESCRIPTION("OMAP High Speed UART driver");
1950MODULE_LICENSE("GPL");
1951MODULE_AUTHOR("Texas Instruments Inc");