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v3.1
   1/*
   2 * mfd.c: driver for High Speed UART device of Intel Medfield platform
   3 *
   4 * Refer pxa.c, 8250.c and some other drivers in drivers/serial/
   5 *
   6 * (C) Copyright 2010 Intel Corporation
   7 *
   8 * This program is free software; you can redistribute it and/or
   9 * modify it under the terms of the GNU General Public License
  10 * as published by the Free Software Foundation; version 2
  11 * of the License.
  12 */
  13
  14/* Notes:
  15 * 1. DMA channel allocation: 0/1 channel are assigned to port 0,
  16 *    2/3 chan to port 1, 4/5 chan to port 3. Even number chans
  17 *    are used for RX, odd chans for TX
  18 *
  19 * 2. The RI/DSR/DCD/DTR are not pinned out, DCD & DSR are always
  20 *    asserted, only when the HW is reset the DDCD and DDSR will
  21 *    be triggered
  22 */
  23
  24#include <linux/module.h>
  25#include <linux/init.h>
  26#include <linux/console.h>
  27#include <linux/sysrq.h>
  28#include <linux/slab.h>
  29#include <linux/serial_reg.h>
  30#include <linux/circ_buf.h>
  31#include <linux/delay.h>
  32#include <linux/interrupt.h>
  33#include <linux/tty.h>
  34#include <linux/tty_flip.h>
  35#include <linux/serial_core.h>
  36#include <linux/serial_mfd.h>
  37#include <linux/dma-mapping.h>
  38#include <linux/pci.h>
  39#include <linux/io.h>
  40#include <linux/debugfs.h>
 
  41
  42#define HSU_DMA_BUF_SIZE	2048
  43
  44#define chan_readl(chan, offset)	readl(chan->reg + offset)
  45#define chan_writel(chan, offset, val)	writel(val, chan->reg + offset)
  46
  47#define mfd_readl(obj, offset)		readl(obj->reg + offset)
  48#define mfd_writel(obj, offset, val)	writel(val, obj->reg + offset)
  49
  50static int hsu_dma_enable;
  51module_param(hsu_dma_enable, int, 0);
  52MODULE_PARM_DESC(hsu_dma_enable,
  53		 "It is a bitmap to set working mode, if bit[x] is 1, then port[x] will work in DMA mode, otherwise in PIO mode.");
  54
  55struct hsu_dma_buffer {
  56	u8		*buf;
  57	dma_addr_t	dma_addr;
  58	u32		dma_size;
  59	u32		ofs;
  60};
  61
  62struct hsu_dma_chan {
  63	u32	id;
  64	enum dma_data_direction	dirt;
  65	struct uart_hsu_port	*uport;
  66	void __iomem		*reg;
  67};
  68
  69struct uart_hsu_port {
  70	struct uart_port        port;
  71	unsigned char           ier;
  72	unsigned char           lcr;
  73	unsigned char           mcr;
  74	unsigned int            lsr_break_flag;
  75	char			name[12];
  76	int			index;
  77	struct device		*dev;
  78
  79	struct hsu_dma_chan	*txc;
  80	struct hsu_dma_chan	*rxc;
  81	struct hsu_dma_buffer	txbuf;
  82	struct hsu_dma_buffer	rxbuf;
  83	int			use_dma;	/* flag for DMA/PIO */
  84	int			running;
  85	int			dma_tx_on;
  86};
  87
  88/* Top level data structure of HSU */
  89struct hsu_port {
  90	void __iomem	*reg;
  91	unsigned long	paddr;
  92	unsigned long	iolen;
  93	u32		irq;
  94
  95	struct uart_hsu_port	port[3];
  96	struct hsu_dma_chan	chans[10];
  97
  98	struct dentry *debugfs;
  99};
 100
 101static inline unsigned int serial_in(struct uart_hsu_port *up, int offset)
 102{
 103	unsigned int val;
 104
 105	if (offset > UART_MSR) {
 106		offset <<= 2;
 107		val = readl(up->port.membase + offset);
 108	} else
 109		val = (unsigned int)readb(up->port.membase + offset);
 110
 111	return val;
 112}
 113
 114static inline void serial_out(struct uart_hsu_port *up, int offset, int value)
 115{
 116	if (offset > UART_MSR) {
 117		offset <<= 2;
 118		writel(value, up->port.membase + offset);
 119	} else {
 120		unsigned char val = value & 0xff;
 121		writeb(val, up->port.membase + offset);
 122	}
 123}
 124
 125#ifdef CONFIG_DEBUG_FS
 126
 127#define HSU_REGS_BUFSIZE	1024
 128
 129static int hsu_show_regs_open(struct inode *inode, struct file *file)
 130{
 131	file->private_data = inode->i_private;
 132	return 0;
 133}
 134
 135static ssize_t port_show_regs(struct file *file, char __user *user_buf,
 136				size_t count, loff_t *ppos)
 137{
 138	struct uart_hsu_port *up = file->private_data;
 139	char *buf;
 140	u32 len = 0;
 141	ssize_t ret;
 142
 143	buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL);
 144	if (!buf)
 145		return 0;
 146
 147	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 148			"MFD HSU port[%d] regs:\n", up->index);
 149
 150	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 151			"=================================\n");
 152	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 153			"IER: \t\t0x%08x\n", serial_in(up, UART_IER));
 154	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 155			"IIR: \t\t0x%08x\n", serial_in(up, UART_IIR));
 156	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 157			"LCR: \t\t0x%08x\n", serial_in(up, UART_LCR));
 158	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 159			"MCR: \t\t0x%08x\n", serial_in(up, UART_MCR));
 160	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 161			"LSR: \t\t0x%08x\n", serial_in(up, UART_LSR));
 162	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 163			"MSR: \t\t0x%08x\n", serial_in(up, UART_MSR));
 164	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 165			"FOR: \t\t0x%08x\n", serial_in(up, UART_FOR));
 166	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 167			"PS: \t\t0x%08x\n", serial_in(up, UART_PS));
 168	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 169			"MUL: \t\t0x%08x\n", serial_in(up, UART_MUL));
 170	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 171			"DIV: \t\t0x%08x\n", serial_in(up, UART_DIV));
 172
 173	if (len > HSU_REGS_BUFSIZE)
 174		len = HSU_REGS_BUFSIZE;
 175
 176	ret =  simple_read_from_buffer(user_buf, count, ppos, buf, len);
 177	kfree(buf);
 178	return ret;
 179}
 180
 181static ssize_t dma_show_regs(struct file *file, char __user *user_buf,
 182				size_t count, loff_t *ppos)
 183{
 184	struct hsu_dma_chan *chan = file->private_data;
 185	char *buf;
 186	u32 len = 0;
 187	ssize_t ret;
 188
 189	buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL);
 190	if (!buf)
 191		return 0;
 192
 193	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 194			"MFD HSU DMA channel [%d] regs:\n", chan->id);
 195
 196	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 197			"=================================\n");
 198	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 199			"CR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_CR));
 200	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 201			"DCR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_DCR));
 202	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 203			"BSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_BSR));
 204	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 205			"MOTSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_MOTSR));
 206	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 207			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0SAR));
 208	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 209			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0TSR));
 210	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 211			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1SAR));
 212	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 213			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1TSR));
 214	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 215			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2SAR));
 216	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 217			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2TSR));
 218	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 219			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3SAR));
 220	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 221			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3TSR));
 222
 223	if (len > HSU_REGS_BUFSIZE)
 224		len = HSU_REGS_BUFSIZE;
 225
 226	ret =  simple_read_from_buffer(user_buf, count, ppos, buf, len);
 227	kfree(buf);
 228	return ret;
 229}
 230
 231static const struct file_operations port_regs_ops = {
 232	.owner		= THIS_MODULE,
 233	.open		= hsu_show_regs_open,
 234	.read		= port_show_regs,
 235	.llseek		= default_llseek,
 236};
 237
 238static const struct file_operations dma_regs_ops = {
 239	.owner		= THIS_MODULE,
 240	.open		= hsu_show_regs_open,
 241	.read		= dma_show_regs,
 242	.llseek		= default_llseek,
 243};
 244
 245static int hsu_debugfs_init(struct hsu_port *hsu)
 246{
 247	int i;
 248	char name[32];
 249
 250	hsu->debugfs = debugfs_create_dir("hsu", NULL);
 251	if (!hsu->debugfs)
 252		return -ENOMEM;
 253
 254	for (i = 0; i < 3; i++) {
 255		snprintf(name, sizeof(name), "port_%d_regs", i);
 256		debugfs_create_file(name, S_IFREG | S_IRUGO,
 257			hsu->debugfs, (void *)(&hsu->port[i]), &port_regs_ops);
 258	}
 259
 260	for (i = 0; i < 6; i++) {
 261		snprintf(name, sizeof(name), "dma_chan_%d_regs", i);
 262		debugfs_create_file(name, S_IFREG | S_IRUGO,
 263			hsu->debugfs, (void *)&hsu->chans[i], &dma_regs_ops);
 264	}
 265
 266	return 0;
 267}
 268
 269static void hsu_debugfs_remove(struct hsu_port *hsu)
 270{
 271	if (hsu->debugfs)
 272		debugfs_remove_recursive(hsu->debugfs);
 273}
 274
 275#else
 276static inline int hsu_debugfs_init(struct hsu_port *hsu)
 277{
 278	return 0;
 279}
 280
 281static inline void hsu_debugfs_remove(struct hsu_port *hsu)
 282{
 283}
 284#endif /* CONFIG_DEBUG_FS */
 285
 286static void serial_hsu_enable_ms(struct uart_port *port)
 287{
 288	struct uart_hsu_port *up =
 289		container_of(port, struct uart_hsu_port, port);
 290
 291	up->ier |= UART_IER_MSI;
 292	serial_out(up, UART_IER, up->ier);
 293}
 294
 295void hsu_dma_tx(struct uart_hsu_port *up)
 296{
 297	struct circ_buf *xmit = &up->port.state->xmit;
 298	struct hsu_dma_buffer *dbuf = &up->txbuf;
 299	int count;
 300
 301	/* test_and_set_bit may be better, but anyway it's in lock protected mode */
 302	if (up->dma_tx_on)
 303		return;
 304
 305	/* Update the circ buf info */
 306	xmit->tail += dbuf->ofs;
 307	xmit->tail &= UART_XMIT_SIZE - 1;
 308
 309	up->port.icount.tx += dbuf->ofs;
 310	dbuf->ofs = 0;
 311
 312	/* Disable the channel */
 313	chan_writel(up->txc, HSU_CH_CR, 0x0);
 314
 315	if (!uart_circ_empty(xmit) && !uart_tx_stopped(&up->port)) {
 316		dma_sync_single_for_device(up->port.dev,
 317					   dbuf->dma_addr,
 318					   dbuf->dma_size,
 319					   DMA_TO_DEVICE);
 320
 321		count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 322		dbuf->ofs = count;
 323
 324		/* Reprogram the channel */
 325		chan_writel(up->txc, HSU_CH_D0SAR, dbuf->dma_addr + xmit->tail);
 326		chan_writel(up->txc, HSU_CH_D0TSR, count);
 327
 328		/* Reenable the channel */
 329		chan_writel(up->txc, HSU_CH_DCR, 0x1
 330						 | (0x1 << 8)
 331						 | (0x1 << 16)
 332						 | (0x1 << 24));
 333		up->dma_tx_on = 1;
 334		chan_writel(up->txc, HSU_CH_CR, 0x1);
 335	}
 336
 337	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 338		uart_write_wakeup(&up->port);
 339}
 340
 341/* The buffer is already cache coherent */
 342void hsu_dma_start_rx_chan(struct hsu_dma_chan *rxc, struct hsu_dma_buffer *dbuf)
 343{
 344	dbuf->ofs = 0;
 345
 346	chan_writel(rxc, HSU_CH_BSR, 32);
 347	chan_writel(rxc, HSU_CH_MOTSR, 4);
 348
 349	chan_writel(rxc, HSU_CH_D0SAR, dbuf->dma_addr);
 350	chan_writel(rxc, HSU_CH_D0TSR, dbuf->dma_size);
 351	chan_writel(rxc, HSU_CH_DCR, 0x1 | (0x1 << 8)
 352					 | (0x1 << 16)
 353					 | (0x1 << 24)	/* timeout bit, see HSU Errata 1 */
 354					 );
 355	chan_writel(rxc, HSU_CH_CR, 0x3);
 356}
 357
 358/* Protected by spin_lock_irqsave(port->lock) */
 359static void serial_hsu_start_tx(struct uart_port *port)
 360{
 361	struct uart_hsu_port *up =
 362		container_of(port, struct uart_hsu_port, port);
 363
 364	if (up->use_dma) {
 365		hsu_dma_tx(up);
 366	} else if (!(up->ier & UART_IER_THRI)) {
 367		up->ier |= UART_IER_THRI;
 368		serial_out(up, UART_IER, up->ier);
 369	}
 370}
 371
 372static void serial_hsu_stop_tx(struct uart_port *port)
 373{
 374	struct uart_hsu_port *up =
 375		container_of(port, struct uart_hsu_port, port);
 376	struct hsu_dma_chan *txc = up->txc;
 377
 378	if (up->use_dma)
 379		chan_writel(txc, HSU_CH_CR, 0x0);
 380	else if (up->ier & UART_IER_THRI) {
 381		up->ier &= ~UART_IER_THRI;
 382		serial_out(up, UART_IER, up->ier);
 383	}
 384}
 385
 386/* This is always called in spinlock protected mode, so
 387 * modify timeout timer is safe here */
 388void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts)
 389{
 390	struct hsu_dma_buffer *dbuf = &up->rxbuf;
 391	struct hsu_dma_chan *chan = up->rxc;
 392	struct uart_port *port = &up->port;
 393	struct tty_struct *tty = port->state->port.tty;
 394	int count;
 395
 396	if (!tty)
 397		return;
 398
 399	/*
 400	 * First need to know how many is already transferred,
 401	 * then check if its a timeout DMA irq, and return
 402	 * the trail bytes out, push them up and reenable the
 403	 * channel
 404	 */
 405
 406	/* Timeout IRQ, need wait some time, see Errata 2 */
 407	if (int_sts & 0xf00)
 408		udelay(2);
 409
 410	/* Stop the channel */
 411	chan_writel(chan, HSU_CH_CR, 0x0);
 412
 413	count = chan_readl(chan, HSU_CH_D0SAR) - dbuf->dma_addr;
 414	if (!count) {
 415		/* Restart the channel before we leave */
 416		chan_writel(chan, HSU_CH_CR, 0x3);
 417		return;
 418	}
 419
 420	dma_sync_single_for_cpu(port->dev, dbuf->dma_addr,
 421			dbuf->dma_size, DMA_FROM_DEVICE);
 422
 423	/*
 424	 * Head will only wrap around when we recycle
 425	 * the DMA buffer, and when that happens, we
 426	 * explicitly set tail to 0. So head will
 427	 * always be greater than tail.
 428	 */
 429	tty_insert_flip_string(tty, dbuf->buf, count);
 430	port->icount.rx += count;
 431
 432	dma_sync_single_for_device(up->port.dev, dbuf->dma_addr,
 433			dbuf->dma_size, DMA_FROM_DEVICE);
 434
 435	/* Reprogram the channel */
 436	chan_writel(chan, HSU_CH_D0SAR, dbuf->dma_addr);
 437	chan_writel(chan, HSU_CH_D0TSR, dbuf->dma_size);
 438	chan_writel(chan, HSU_CH_DCR, 0x1
 439					 | (0x1 << 8)
 440					 | (0x1 << 16)
 441					 | (0x1 << 24)	/* timeout bit, see HSU Errata 1 */
 442					 );
 443	tty_flip_buffer_push(tty);
 444
 445	chan_writel(chan, HSU_CH_CR, 0x3);
 446
 447}
 448
 449static void serial_hsu_stop_rx(struct uart_port *port)
 450{
 451	struct uart_hsu_port *up =
 452		container_of(port, struct uart_hsu_port, port);
 453	struct hsu_dma_chan *chan = up->rxc;
 454
 455	if (up->use_dma)
 456		chan_writel(chan, HSU_CH_CR, 0x2);
 457	else {
 458		up->ier &= ~UART_IER_RLSI;
 459		up->port.read_status_mask &= ~UART_LSR_DR;
 460		serial_out(up, UART_IER, up->ier);
 461	}
 462}
 463
 464static inline void receive_chars(struct uart_hsu_port *up, int *status)
 465{
 466	struct tty_struct *tty = up->port.state->port.tty;
 467	unsigned int ch, flag;
 468	unsigned int max_count = 256;
 469
 470	if (!tty)
 471		return;
 472
 473	do {
 474		ch = serial_in(up, UART_RX);
 475		flag = TTY_NORMAL;
 476		up->port.icount.rx++;
 477
 478		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
 479				       UART_LSR_FE | UART_LSR_OE))) {
 480
 481			dev_warn(up->dev, "We really rush into ERR/BI case"
 482				"status = 0x%02x", *status);
 483			/* For statistics only */
 484			if (*status & UART_LSR_BI) {
 485				*status &= ~(UART_LSR_FE | UART_LSR_PE);
 486				up->port.icount.brk++;
 487				/*
 488				 * We do the SysRQ and SAK checking
 489				 * here because otherwise the break
 490				 * may get masked by ignore_status_mask
 491				 * or read_status_mask.
 492				 */
 493				if (uart_handle_break(&up->port))
 494					goto ignore_char;
 495			} else if (*status & UART_LSR_PE)
 496				up->port.icount.parity++;
 497			else if (*status & UART_LSR_FE)
 498				up->port.icount.frame++;
 499			if (*status & UART_LSR_OE)
 500				up->port.icount.overrun++;
 501
 502			/* Mask off conditions which should be ignored. */
 503			*status &= up->port.read_status_mask;
 504
 505#ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
 506			if (up->port.cons &&
 507				up->port.cons->index == up->port.line) {
 508				/* Recover the break flag from console xmit */
 509				*status |= up->lsr_break_flag;
 510				up->lsr_break_flag = 0;
 511			}
 512#endif
 513			if (*status & UART_LSR_BI) {
 514				flag = TTY_BREAK;
 515			} else if (*status & UART_LSR_PE)
 516				flag = TTY_PARITY;
 517			else if (*status & UART_LSR_FE)
 518				flag = TTY_FRAME;
 519		}
 520
 521		if (uart_handle_sysrq_char(&up->port, ch))
 522			goto ignore_char;
 523
 524		uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
 525	ignore_char:
 526		*status = serial_in(up, UART_LSR);
 527	} while ((*status & UART_LSR_DR) && max_count--);
 528	tty_flip_buffer_push(tty);
 529}
 530
 531static void transmit_chars(struct uart_hsu_port *up)
 532{
 533	struct circ_buf *xmit = &up->port.state->xmit;
 534	int count;
 535
 536	if (up->port.x_char) {
 537		serial_out(up, UART_TX, up->port.x_char);
 538		up->port.icount.tx++;
 539		up->port.x_char = 0;
 540		return;
 541	}
 542	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 543		serial_hsu_stop_tx(&up->port);
 544		return;
 545	}
 546
 547	/* The IRQ is for TX FIFO half-empty */
 548	count = up->port.fifosize / 2;
 549
 550	do {
 551		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
 552		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 553
 554		up->port.icount.tx++;
 555		if (uart_circ_empty(xmit))
 556			break;
 557	} while (--count > 0);
 558
 559	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 560		uart_write_wakeup(&up->port);
 561
 562	if (uart_circ_empty(xmit))
 563		serial_hsu_stop_tx(&up->port);
 564}
 565
 566static inline void check_modem_status(struct uart_hsu_port *up)
 567{
 568	int status;
 569
 570	status = serial_in(up, UART_MSR);
 571
 572	if ((status & UART_MSR_ANY_DELTA) == 0)
 573		return;
 574
 575	if (status & UART_MSR_TERI)
 576		up->port.icount.rng++;
 577	if (status & UART_MSR_DDSR)
 578		up->port.icount.dsr++;
 579	/* We may only get DDCD when HW init and reset */
 580	if (status & UART_MSR_DDCD)
 581		uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
 582	/* Will start/stop_tx accordingly */
 583	if (status & UART_MSR_DCTS)
 584		uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
 585
 586	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 587}
 588
 589/*
 590 * This handles the interrupt from one port.
 591 */
 592static irqreturn_t port_irq(int irq, void *dev_id)
 593{
 594	struct uart_hsu_port *up = dev_id;
 595	unsigned int iir, lsr;
 596	unsigned long flags;
 597
 598	if (unlikely(!up->running))
 599		return IRQ_NONE;
 600
 601	spin_lock_irqsave(&up->port.lock, flags);
 602	if (up->use_dma) {
 603		lsr = serial_in(up, UART_LSR);
 604		if (unlikely(lsr & (UART_LSR_BI | UART_LSR_PE |
 605				       UART_LSR_FE | UART_LSR_OE)))
 606			dev_warn(up->dev,
 607				"Got lsr irq while using DMA, lsr = 0x%2x\n",
 608				lsr);
 609		check_modem_status(up);
 610		spin_unlock_irqrestore(&up->port.lock, flags);
 611		return IRQ_HANDLED;
 612	}
 613
 614	iir = serial_in(up, UART_IIR);
 615	if (iir & UART_IIR_NO_INT) {
 616		spin_unlock_irqrestore(&up->port.lock, flags);
 617		return IRQ_NONE;
 618	}
 619
 620	lsr = serial_in(up, UART_LSR);
 621	if (lsr & UART_LSR_DR)
 622		receive_chars(up, &lsr);
 623	check_modem_status(up);
 624
 625	/* lsr will be renewed during the receive_chars */
 626	if (lsr & UART_LSR_THRE)
 627		transmit_chars(up);
 628
 629	spin_unlock_irqrestore(&up->port.lock, flags);
 630	return IRQ_HANDLED;
 631}
 632
 633static inline void dma_chan_irq(struct hsu_dma_chan *chan)
 634{
 635	struct uart_hsu_port *up = chan->uport;
 636	unsigned long flags;
 637	u32 int_sts;
 638
 639	spin_lock_irqsave(&up->port.lock, flags);
 640
 641	if (!up->use_dma || !up->running)
 642		goto exit;
 643
 644	/*
 645	 * No matter what situation, need read clear the IRQ status
 646	 * There is a bug, see Errata 5, HSD 2900918
 647	 */
 648	int_sts = chan_readl(chan, HSU_CH_SR);
 649
 650	/* Rx channel */
 651	if (chan->dirt == DMA_FROM_DEVICE)
 652		hsu_dma_rx(up, int_sts);
 653
 654	/* Tx channel */
 655	if (chan->dirt == DMA_TO_DEVICE) {
 656		chan_writel(chan, HSU_CH_CR, 0x0);
 657		up->dma_tx_on = 0;
 658		hsu_dma_tx(up);
 659	}
 660
 661exit:
 662	spin_unlock_irqrestore(&up->port.lock, flags);
 663	return;
 664}
 665
 666static irqreturn_t dma_irq(int irq, void *dev_id)
 667{
 668	struct hsu_port *hsu = dev_id;
 669	u32 int_sts, i;
 670
 671	int_sts = mfd_readl(hsu, HSU_GBL_DMAISR);
 672
 673	/* Currently we only have 6 channels may be used */
 674	for (i = 0; i < 6; i++) {
 675		if (int_sts & 0x1)
 676			dma_chan_irq(&hsu->chans[i]);
 677		int_sts >>= 1;
 678	}
 679
 680	return IRQ_HANDLED;
 681}
 682
 683static unsigned int serial_hsu_tx_empty(struct uart_port *port)
 684{
 685	struct uart_hsu_port *up =
 686		container_of(port, struct uart_hsu_port, port);
 687	unsigned long flags;
 688	unsigned int ret;
 689
 690	spin_lock_irqsave(&up->port.lock, flags);
 691	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
 692	spin_unlock_irqrestore(&up->port.lock, flags);
 693
 694	return ret;
 695}
 696
 697static unsigned int serial_hsu_get_mctrl(struct uart_port *port)
 698{
 699	struct uart_hsu_port *up =
 700		container_of(port, struct uart_hsu_port, port);
 701	unsigned char status;
 702	unsigned int ret;
 703
 704	status = serial_in(up, UART_MSR);
 705
 706	ret = 0;
 707	if (status & UART_MSR_DCD)
 708		ret |= TIOCM_CAR;
 709	if (status & UART_MSR_RI)
 710		ret |= TIOCM_RNG;
 711	if (status & UART_MSR_DSR)
 712		ret |= TIOCM_DSR;
 713	if (status & UART_MSR_CTS)
 714		ret |= TIOCM_CTS;
 715	return ret;
 716}
 717
 718static void serial_hsu_set_mctrl(struct uart_port *port, unsigned int mctrl)
 719{
 720	struct uart_hsu_port *up =
 721		container_of(port, struct uart_hsu_port, port);
 722	unsigned char mcr = 0;
 723
 724	if (mctrl & TIOCM_RTS)
 725		mcr |= UART_MCR_RTS;
 726	if (mctrl & TIOCM_DTR)
 727		mcr |= UART_MCR_DTR;
 728	if (mctrl & TIOCM_OUT1)
 729		mcr |= UART_MCR_OUT1;
 730	if (mctrl & TIOCM_OUT2)
 731		mcr |= UART_MCR_OUT2;
 732	if (mctrl & TIOCM_LOOP)
 733		mcr |= UART_MCR_LOOP;
 734
 735	mcr |= up->mcr;
 736
 737	serial_out(up, UART_MCR, mcr);
 738}
 739
 740static void serial_hsu_break_ctl(struct uart_port *port, int break_state)
 741{
 742	struct uart_hsu_port *up =
 743		container_of(port, struct uart_hsu_port, port);
 744	unsigned long flags;
 745
 746	spin_lock_irqsave(&up->port.lock, flags);
 747	if (break_state == -1)
 748		up->lcr |= UART_LCR_SBC;
 749	else
 750		up->lcr &= ~UART_LCR_SBC;
 751	serial_out(up, UART_LCR, up->lcr);
 752	spin_unlock_irqrestore(&up->port.lock, flags);
 753}
 754
 755/*
 756 * What special to do:
 757 * 1. chose the 64B fifo mode
 758 * 2. start dma or pio depends on configuration
 759 * 3. we only allocate dma memory when needed
 760 */
 761static int serial_hsu_startup(struct uart_port *port)
 762{
 763	struct uart_hsu_port *up =
 764		container_of(port, struct uart_hsu_port, port);
 765	unsigned long flags;
 766
 
 
 767	/*
 768	 * Clear the FIFO buffers and disable them.
 769	 * (they will be reenabled in set_termios())
 770	 */
 771	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
 772	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
 773			UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
 774	serial_out(up, UART_FCR, 0);
 775
 776	/* Clear the interrupt registers. */
 777	(void) serial_in(up, UART_LSR);
 778	(void) serial_in(up, UART_RX);
 779	(void) serial_in(up, UART_IIR);
 780	(void) serial_in(up, UART_MSR);
 781
 782	/* Now, initialize the UART, default is 8n1 */
 783	serial_out(up, UART_LCR, UART_LCR_WLEN8);
 784
 785	spin_lock_irqsave(&up->port.lock, flags);
 786
 787	up->port.mctrl |= TIOCM_OUT2;
 788	serial_hsu_set_mctrl(&up->port, up->port.mctrl);
 789
 790	/*
 791	 * Finally, enable interrupts.  Note: Modem status interrupts
 792	 * are set via set_termios(), which will be occurring imminently
 793	 * anyway, so we don't enable them here.
 794	 */
 795	if (!up->use_dma)
 796		up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE;
 797	else
 798		up->ier = 0;
 799	serial_out(up, UART_IER, up->ier);
 800
 801	spin_unlock_irqrestore(&up->port.lock, flags);
 802
 803	/* DMA init */
 804	if (up->use_dma) {
 805		struct hsu_dma_buffer *dbuf;
 806		struct circ_buf *xmit = &port->state->xmit;
 807
 808		up->dma_tx_on = 0;
 809
 810		/* First allocate the RX buffer */
 811		dbuf = &up->rxbuf;
 812		dbuf->buf = kzalloc(HSU_DMA_BUF_SIZE, GFP_KERNEL);
 813		if (!dbuf->buf) {
 814			up->use_dma = 0;
 815			goto exit;
 816		}
 817		dbuf->dma_addr = dma_map_single(port->dev,
 818						dbuf->buf,
 819						HSU_DMA_BUF_SIZE,
 820						DMA_FROM_DEVICE);
 821		dbuf->dma_size = HSU_DMA_BUF_SIZE;
 822
 823		/* Start the RX channel right now */
 824		hsu_dma_start_rx_chan(up->rxc, dbuf);
 825
 826		/* Next init the TX DMA */
 827		dbuf = &up->txbuf;
 828		dbuf->buf = xmit->buf;
 829		dbuf->dma_addr = dma_map_single(port->dev,
 830					       dbuf->buf,
 831					       UART_XMIT_SIZE,
 832					       DMA_TO_DEVICE);
 833		dbuf->dma_size = UART_XMIT_SIZE;
 834
 835		/* This should not be changed all around */
 836		chan_writel(up->txc, HSU_CH_BSR, 32);
 837		chan_writel(up->txc, HSU_CH_MOTSR, 4);
 838		dbuf->ofs = 0;
 839	}
 840
 841exit:
 842	 /* And clear the interrupt registers again for luck. */
 843	(void) serial_in(up, UART_LSR);
 844	(void) serial_in(up, UART_RX);
 845	(void) serial_in(up, UART_IIR);
 846	(void) serial_in(up, UART_MSR);
 847
 848	up->running = 1;
 849	return 0;
 850}
 851
 852static void serial_hsu_shutdown(struct uart_port *port)
 853{
 854	struct uart_hsu_port *up =
 855		container_of(port, struct uart_hsu_port, port);
 856	unsigned long flags;
 857
 858	/* Disable interrupts from this port */
 859	up->ier = 0;
 860	serial_out(up, UART_IER, 0);
 861	up->running = 0;
 862
 863	spin_lock_irqsave(&up->port.lock, flags);
 864	up->port.mctrl &= ~TIOCM_OUT2;
 865	serial_hsu_set_mctrl(&up->port, up->port.mctrl);
 866	spin_unlock_irqrestore(&up->port.lock, flags);
 867
 868	/* Disable break condition and FIFOs */
 869	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
 870	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
 871				  UART_FCR_CLEAR_RCVR |
 872				  UART_FCR_CLEAR_XMIT);
 873	serial_out(up, UART_FCR, 0);
 
 
 874}
 875
 876static void
 877serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios,
 878		       struct ktermios *old)
 879{
 880	struct uart_hsu_port *up =
 881			container_of(port, struct uart_hsu_port, port);
 882	struct tty_struct *tty = port->state->port.tty;
 883	unsigned char cval, fcr = 0;
 884	unsigned long flags;
 885	unsigned int baud, quot;
 886	u32 ps, mul;
 887
 888	switch (termios->c_cflag & CSIZE) {
 889	case CS5:
 890		cval = UART_LCR_WLEN5;
 891		break;
 892	case CS6:
 893		cval = UART_LCR_WLEN6;
 894		break;
 895	case CS7:
 896		cval = UART_LCR_WLEN7;
 897		break;
 898	default:
 899	case CS8:
 900		cval = UART_LCR_WLEN8;
 901		break;
 902	}
 903
 904	/* CMSPAR isn't supported by this driver */
 905	if (tty)
 906		tty->termios->c_cflag &= ~CMSPAR;
 907
 908	if (termios->c_cflag & CSTOPB)
 909		cval |= UART_LCR_STOP;
 910	if (termios->c_cflag & PARENB)
 911		cval |= UART_LCR_PARITY;
 912	if (!(termios->c_cflag & PARODD))
 913		cval |= UART_LCR_EPAR;
 914
 915	/*
 916	 * The base clk is 50Mhz, and the baud rate come from:
 917	 *	baud = 50M * MUL / (DIV * PS * DLAB)
 918	 *
 919	 * For those basic low baud rate we can get the direct
 920	 * scalar from 2746800, like 115200 = 2746800/24. For those
 921	 * higher baud rate, we handle them case by case, mainly by
 922	 * adjusting the MUL/PS registers, and DIV register is kept
 923	 * as default value 0x3d09 to make things simple
 924	 */
 925	baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 926
 927	quot = 1;
 928	ps = 0x10;
 929	mul = 0x3600;
 930	switch (baud) {
 931	case 3500000:
 932		mul = 0x3345;
 933		ps = 0xC;
 934		break;
 935	case 1843200:
 936		mul = 0x2400;
 937		break;
 938	case 3000000:
 939	case 2500000:
 940	case 2000000:
 941	case 1500000:
 942	case 1000000:
 943	case 500000:
 944		/* mul/ps/quot = 0x9C4/0x10/0x1 will make a 500000 bps */
 945		mul = baud / 500000 * 0x9C4;
 946		break;
 947	default:
 948		/* Use uart_get_divisor to get quot for other baud rates */
 949		quot = 0;
 950	}
 951
 952	if (!quot)
 953		quot = uart_get_divisor(port, baud);
 954
 955	if ((up->port.uartclk / quot) < (2400 * 16))
 956		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_1B;
 957	else if ((up->port.uartclk / quot) < (230400 * 16))
 958		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_16B;
 959	else
 960		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_32B;
 961
 962	fcr |= UART_FCR_HSU_64B_FIFO;
 963
 964	/*
 965	 * Ok, we're now changing the port state.  Do it with
 966	 * interrupts disabled.
 967	 */
 968	spin_lock_irqsave(&up->port.lock, flags);
 969
 970	/* Update the per-port timeout */
 971	uart_update_timeout(port, termios->c_cflag, baud);
 972
 973	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
 974	if (termios->c_iflag & INPCK)
 975		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 976	if (termios->c_iflag & (BRKINT | PARMRK))
 977		up->port.read_status_mask |= UART_LSR_BI;
 978
 979	/* Characters to ignore */
 980	up->port.ignore_status_mask = 0;
 981	if (termios->c_iflag & IGNPAR)
 982		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 983	if (termios->c_iflag & IGNBRK) {
 984		up->port.ignore_status_mask |= UART_LSR_BI;
 985		/*
 986		 * If we're ignoring parity and break indicators,
 987		 * ignore overruns too (for real raw support).
 988		 */
 989		if (termios->c_iflag & IGNPAR)
 990			up->port.ignore_status_mask |= UART_LSR_OE;
 991	}
 992
 993	/* Ignore all characters if CREAD is not set */
 994	if ((termios->c_cflag & CREAD) == 0)
 995		up->port.ignore_status_mask |= UART_LSR_DR;
 996
 997	/*
 998	 * CTS flow control flag and modem status interrupts, disable
 999	 * MSI by default
1000	 */
1001	up->ier &= ~UART_IER_MSI;
1002	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
1003		up->ier |= UART_IER_MSI;
1004
1005	serial_out(up, UART_IER, up->ier);
1006
1007	if (termios->c_cflag & CRTSCTS)
1008		up->mcr |= UART_MCR_AFE | UART_MCR_RTS;
1009	else
1010		up->mcr &= ~UART_MCR_AFE;
1011
1012	serial_out(up, UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
1013	serial_out(up, UART_DLL, quot & 0xff);		/* LS of divisor */
1014	serial_out(up, UART_DLM, quot >> 8);		/* MS of divisor */
1015	serial_out(up, UART_LCR, cval);			/* reset DLAB */
1016	serial_out(up, UART_MUL, mul);			/* set MUL */
1017	serial_out(up, UART_PS, ps);			/* set PS */
1018	up->lcr = cval;					/* Save LCR */
1019	serial_hsu_set_mctrl(&up->port, up->port.mctrl);
1020	serial_out(up, UART_FCR, fcr);
1021	spin_unlock_irqrestore(&up->port.lock, flags);
1022}
1023
1024static void
1025serial_hsu_pm(struct uart_port *port, unsigned int state,
1026	      unsigned int oldstate)
1027{
1028}
1029
1030static void serial_hsu_release_port(struct uart_port *port)
1031{
1032}
1033
1034static int serial_hsu_request_port(struct uart_port *port)
1035{
1036	return 0;
1037}
1038
1039static void serial_hsu_config_port(struct uart_port *port, int flags)
1040{
1041	struct uart_hsu_port *up =
1042		container_of(port, struct uart_hsu_port, port);
1043	up->port.type = PORT_MFD;
1044}
1045
1046static int
1047serial_hsu_verify_port(struct uart_port *port, struct serial_struct *ser)
1048{
1049	/* We don't want the core code to modify any port params */
1050	return -EINVAL;
1051}
1052
1053static const char *
1054serial_hsu_type(struct uart_port *port)
1055{
1056	struct uart_hsu_port *up =
1057		container_of(port, struct uart_hsu_port, port);
1058	return up->name;
1059}
1060
1061/* Mainly for uart console use */
1062static struct uart_hsu_port *serial_hsu_ports[3];
1063static struct uart_driver serial_hsu_reg;
1064
1065#ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
1066
1067#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1068
1069/* Wait for transmitter & holding register to empty */
1070static inline void wait_for_xmitr(struct uart_hsu_port *up)
1071{
1072	unsigned int status, tmout = 1000;
1073
1074	/* Wait up to 1ms for the character to be sent. */
1075	do {
1076		status = serial_in(up, UART_LSR);
1077
1078		if (status & UART_LSR_BI)
1079			up->lsr_break_flag = UART_LSR_BI;
1080
1081		if (--tmout == 0)
1082			break;
1083		udelay(1);
1084	} while (!(status & BOTH_EMPTY));
1085
1086	/* Wait up to 1s for flow control if necessary */
1087	if (up->port.flags & UPF_CONS_FLOW) {
1088		tmout = 1000000;
1089		while (--tmout &&
1090		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
1091			udelay(1);
1092	}
1093}
1094
1095static void serial_hsu_console_putchar(struct uart_port *port, int ch)
1096{
1097	struct uart_hsu_port *up =
1098		container_of(port, struct uart_hsu_port, port);
1099
1100	wait_for_xmitr(up);
1101	serial_out(up, UART_TX, ch);
1102}
1103
1104/*
1105 * Print a string to the serial port trying not to disturb
1106 * any possible real use of the port...
1107 *
1108 *	The console_lock must be held when we get here.
1109 */
1110static void
1111serial_hsu_console_write(struct console *co, const char *s, unsigned int count)
1112{
1113	struct uart_hsu_port *up = serial_hsu_ports[co->index];
1114	unsigned long flags;
1115	unsigned int ier;
1116	int locked = 1;
1117
1118	local_irq_save(flags);
1119	if (up->port.sysrq)
1120		locked = 0;
1121	else if (oops_in_progress) {
1122		locked = spin_trylock(&up->port.lock);
1123	} else
1124		spin_lock(&up->port.lock);
1125
1126	/* First save the IER then disable the interrupts */
1127	ier = serial_in(up, UART_IER);
1128	serial_out(up, UART_IER, 0);
1129
1130	uart_console_write(&up->port, s, count, serial_hsu_console_putchar);
1131
1132	/*
1133	 * Finally, wait for transmitter to become empty
1134	 * and restore the IER
1135	 */
1136	wait_for_xmitr(up);
1137	serial_out(up, UART_IER, ier);
1138
1139	if (locked)
1140		spin_unlock(&up->port.lock);
1141	local_irq_restore(flags);
1142}
1143
1144static struct console serial_hsu_console;
1145
1146static int __init
1147serial_hsu_console_setup(struct console *co, char *options)
1148{
1149	struct uart_hsu_port *up;
1150	int baud = 115200;
1151	int bits = 8;
1152	int parity = 'n';
1153	int flow = 'n';
1154	int ret;
1155
1156	if (co->index == -1 || co->index >= serial_hsu_reg.nr)
1157		co->index = 0;
1158	up = serial_hsu_ports[co->index];
1159	if (!up)
1160		return -ENODEV;
1161
1162	if (options)
1163		uart_parse_options(options, &baud, &parity, &bits, &flow);
1164
1165	ret = uart_set_options(&up->port, co, baud, parity, bits, flow);
1166
1167	return ret;
1168}
1169
1170static struct console serial_hsu_console = {
1171	.name		= "ttyMFD",
1172	.write		= serial_hsu_console_write,
1173	.device		= uart_console_device,
1174	.setup		= serial_hsu_console_setup,
1175	.flags		= CON_PRINTBUFFER,
1176	.index		= 2,
1177	.data		= &serial_hsu_reg,
1178};
 
 
 
 
1179#endif
1180
1181struct uart_ops serial_hsu_pops = {
1182	.tx_empty	= serial_hsu_tx_empty,
1183	.set_mctrl	= serial_hsu_set_mctrl,
1184	.get_mctrl	= serial_hsu_get_mctrl,
1185	.stop_tx	= serial_hsu_stop_tx,
1186	.start_tx	= serial_hsu_start_tx,
1187	.stop_rx	= serial_hsu_stop_rx,
1188	.enable_ms	= serial_hsu_enable_ms,
1189	.break_ctl	= serial_hsu_break_ctl,
1190	.startup	= serial_hsu_startup,
1191	.shutdown	= serial_hsu_shutdown,
1192	.set_termios	= serial_hsu_set_termios,
1193	.pm		= serial_hsu_pm,
1194	.type		= serial_hsu_type,
1195	.release_port	= serial_hsu_release_port,
1196	.request_port	= serial_hsu_request_port,
1197	.config_port	= serial_hsu_config_port,
1198	.verify_port	= serial_hsu_verify_port,
1199};
1200
1201static struct uart_driver serial_hsu_reg = {
1202	.owner		= THIS_MODULE,
1203	.driver_name	= "MFD serial",
1204	.dev_name	= "ttyMFD",
1205	.major		= TTY_MAJOR,
1206	.minor		= 128,
1207	.nr		= 3,
 
1208};
1209
1210#ifdef CONFIG_PM
1211static int serial_hsu_suspend(struct pci_dev *pdev, pm_message_t state)
1212{
1213	void *priv = pci_get_drvdata(pdev);
1214	struct uart_hsu_port *up;
1215
1216	/* Make sure this is not the internal dma controller */
1217	if (priv && (pdev->device != 0x081E)) {
1218		up = priv;
1219		uart_suspend_port(&serial_hsu_reg, &up->port);
1220	}
1221
1222	pci_save_state(pdev);
1223	pci_set_power_state(pdev, pci_choose_state(pdev, state));
1224        return 0;
1225}
1226
1227static int serial_hsu_resume(struct pci_dev *pdev)
1228{
1229	void *priv = pci_get_drvdata(pdev);
1230	struct uart_hsu_port *up;
1231	int ret;
1232
1233	pci_set_power_state(pdev, PCI_D0);
1234	pci_restore_state(pdev);
1235
1236	ret = pci_enable_device(pdev);
1237	if (ret)
1238		dev_warn(&pdev->dev,
1239			"HSU: can't re-enable device, try to continue\n");
1240
1241	if (priv && (pdev->device != 0x081E)) {
1242		up = priv;
1243		uart_resume_port(&serial_hsu_reg, &up->port);
1244	}
1245	return 0;
1246}
1247#else
1248#define serial_hsu_suspend	NULL
1249#define serial_hsu_resume	NULL
1250#endif
1251
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1252/* temp global pointer before we settle down on using one or four PCI dev */
1253static struct hsu_port *phsu;
1254
1255static int serial_hsu_probe(struct pci_dev *pdev,
1256				const struct pci_device_id *ent)
1257{
1258	struct uart_hsu_port *uport;
1259	int index, ret;
1260
1261	printk(KERN_INFO "HSU: found PCI Serial controller(ID: %04x:%04x)\n",
1262		pdev->vendor, pdev->device);
1263
1264	switch (pdev->device) {
1265	case 0x081B:
1266		index = 0;
1267		break;
1268	case 0x081C:
1269		index = 1;
1270		break;
1271	case 0x081D:
1272		index = 2;
1273		break;
1274	case 0x081E:
1275		/* internal DMA controller */
1276		index = 3;
1277		break;
1278	default:
1279		dev_err(&pdev->dev, "HSU: out of index!");
1280		return -ENODEV;
1281	}
1282
1283	ret = pci_enable_device(pdev);
1284	if (ret)
1285		return ret;
1286
1287	if (index == 3) {
1288		/* DMA controller */
1289		ret = request_irq(pdev->irq, dma_irq, 0, "hsu_dma", phsu);
1290		if (ret) {
1291			dev_err(&pdev->dev, "can not get IRQ\n");
1292			goto err_disable;
1293		}
1294		pci_set_drvdata(pdev, phsu);
1295	} else {
1296		/* UART port 0~2 */
1297		uport = &phsu->port[index];
1298		uport->port.irq = pdev->irq;
1299		uport->port.dev = &pdev->dev;
1300		uport->dev = &pdev->dev;
1301
1302		ret = request_irq(pdev->irq, port_irq, 0, uport->name, uport);
1303		if (ret) {
1304			dev_err(&pdev->dev, "can not get IRQ\n");
1305			goto err_disable;
1306		}
1307		uart_add_one_port(&serial_hsu_reg, &uport->port);
1308
1309#ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
1310		if (index == 2) {
1311			register_console(&serial_hsu_console);
1312			uport->port.cons = &serial_hsu_console;
1313		}
1314#endif
1315		pci_set_drvdata(pdev, uport);
1316	}
1317
 
 
 
1318	return 0;
1319
1320err_disable:
1321	pci_disable_device(pdev);
1322	return ret;
1323}
1324
1325static void hsu_global_init(void)
1326{
1327	struct hsu_port *hsu;
1328	struct uart_hsu_port *uport;
1329	struct hsu_dma_chan *dchan;
1330	int i, ret;
1331
1332	hsu = kzalloc(sizeof(struct hsu_port), GFP_KERNEL);
1333	if (!hsu)
1334		return;
1335
1336	/* Get basic io resource and map it */
1337	hsu->paddr = 0xffa28000;
1338	hsu->iolen = 0x1000;
1339
1340	if (!(request_mem_region(hsu->paddr, hsu->iolen, "HSU global")))
1341		pr_warning("HSU: error in request mem region\n");
1342
1343	hsu->reg = ioremap_nocache((unsigned long)hsu->paddr, hsu->iolen);
1344	if (!hsu->reg) {
1345		pr_err("HSU: error in ioremap\n");
1346		ret = -ENOMEM;
1347		goto err_free_region;
1348	}
1349
1350	/* Initialise the 3 UART ports */
1351	uport = hsu->port;
1352	for (i = 0; i < 3; i++) {
1353		uport->port.type = PORT_MFD;
1354		uport->port.iotype = UPIO_MEM;
1355		uport->port.mapbase = (resource_size_t)hsu->paddr
1356					+ HSU_PORT_REG_OFFSET
1357					+ i * HSU_PORT_REG_LENGTH;
1358		uport->port.membase = hsu->reg + HSU_PORT_REG_OFFSET
1359					+ i * HSU_PORT_REG_LENGTH;
1360
1361		sprintf(uport->name, "hsu_port%d", i);
1362		uport->port.fifosize = 64;
1363		uport->port.ops = &serial_hsu_pops;
1364		uport->port.line = i;
1365		uport->port.flags = UPF_IOREMAP;
1366		/* set the scalable maxim support rate to 2746800 bps */
1367		uport->port.uartclk = 115200 * 24 * 16;
1368
1369		uport->running = 0;
1370		uport->txc = &hsu->chans[i * 2];
1371		uport->rxc = &hsu->chans[i * 2 + 1];
1372
1373		serial_hsu_ports[i] = uport;
1374		uport->index = i;
1375
1376		if (hsu_dma_enable & (1<<i))
1377			uport->use_dma = 1;
1378		else
1379			uport->use_dma = 0;
1380
1381		uport++;
1382	}
1383
1384	/* Initialise 6 dma channels */
1385	dchan = hsu->chans;
1386	for (i = 0; i < 6; i++) {
1387		dchan->id = i;
1388		dchan->dirt = (i & 0x1) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1389		dchan->uport = &hsu->port[i/2];
1390		dchan->reg = hsu->reg + HSU_DMA_CHANS_REG_OFFSET +
1391				i * HSU_DMA_CHANS_REG_LENGTH;
1392
1393		dchan++;
1394	}
1395
1396	phsu = hsu;
1397	hsu_debugfs_init(hsu);
1398	return;
1399
1400err_free_region:
1401	release_mem_region(hsu->paddr, hsu->iolen);
1402	kfree(hsu);
1403	return;
1404}
1405
1406static void serial_hsu_remove(struct pci_dev *pdev)
1407{
1408	void *priv = pci_get_drvdata(pdev);
1409	struct uart_hsu_port *up;
1410
1411	if (!priv)
1412		return;
1413
 
 
 
1414	/* For port 0/1/2, priv is the address of uart_hsu_port */
1415	if (pdev->device != 0x081E) {
1416		up = priv;
1417		uart_remove_one_port(&serial_hsu_reg, &up->port);
1418	}
1419
1420	pci_set_drvdata(pdev, NULL);
1421	free_irq(pdev->irq, priv);
1422	pci_disable_device(pdev);
1423}
1424
1425/* First 3 are UART ports, and the 4th is the DMA */
1426static const struct pci_device_id pci_ids[] __devinitdata = {
1427	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081B) },
1428	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081C) },
1429	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081D) },
1430	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081E) },
1431	{},
1432};
1433
1434static struct pci_driver hsu_pci_driver = {
1435	.name =		"HSU serial",
1436	.id_table =	pci_ids,
1437	.probe =	serial_hsu_probe,
1438	.remove =	__devexit_p(serial_hsu_remove),
1439	.suspend =	serial_hsu_suspend,
1440	.resume	=	serial_hsu_resume,
 
 
 
1441};
1442
1443static int __init hsu_pci_init(void)
1444{
1445	int ret;
1446
1447	hsu_global_init();
1448
1449	ret = uart_register_driver(&serial_hsu_reg);
1450	if (ret)
1451		return ret;
1452
1453	return pci_register_driver(&hsu_pci_driver);
1454}
1455
1456static void __exit hsu_pci_exit(void)
1457{
1458	pci_unregister_driver(&hsu_pci_driver);
1459	uart_unregister_driver(&serial_hsu_reg);
1460
1461	hsu_debugfs_remove(phsu);
1462
1463	kfree(phsu);
1464}
1465
1466module_init(hsu_pci_init);
1467module_exit(hsu_pci_exit);
1468
1469MODULE_LICENSE("GPL v2");
1470MODULE_ALIAS("platform:medfield-hsu");
v3.5.6
   1/*
   2 * mfd.c: driver for High Speed UART device of Intel Medfield platform
   3 *
   4 * Refer pxa.c, 8250.c and some other drivers in drivers/serial/
   5 *
   6 * (C) Copyright 2010 Intel Corporation
   7 *
   8 * This program is free software; you can redistribute it and/or
   9 * modify it under the terms of the GNU General Public License
  10 * as published by the Free Software Foundation; version 2
  11 * of the License.
  12 */
  13
  14/* Notes:
  15 * 1. DMA channel allocation: 0/1 channel are assigned to port 0,
  16 *    2/3 chan to port 1, 4/5 chan to port 3. Even number chans
  17 *    are used for RX, odd chans for TX
  18 *
  19 * 2. The RI/DSR/DCD/DTR are not pinned out, DCD & DSR are always
  20 *    asserted, only when the HW is reset the DDCD and DDSR will
  21 *    be triggered
  22 */
  23
  24#include <linux/module.h>
  25#include <linux/init.h>
  26#include <linux/console.h>
  27#include <linux/sysrq.h>
  28#include <linux/slab.h>
  29#include <linux/serial_reg.h>
  30#include <linux/circ_buf.h>
  31#include <linux/delay.h>
  32#include <linux/interrupt.h>
  33#include <linux/tty.h>
  34#include <linux/tty_flip.h>
  35#include <linux/serial_core.h>
  36#include <linux/serial_mfd.h>
  37#include <linux/dma-mapping.h>
  38#include <linux/pci.h>
  39#include <linux/io.h>
  40#include <linux/debugfs.h>
  41#include <linux/pm_runtime.h>
  42
  43#define HSU_DMA_BUF_SIZE	2048
  44
  45#define chan_readl(chan, offset)	readl(chan->reg + offset)
  46#define chan_writel(chan, offset, val)	writel(val, chan->reg + offset)
  47
  48#define mfd_readl(obj, offset)		readl(obj->reg + offset)
  49#define mfd_writel(obj, offset, val)	writel(val, obj->reg + offset)
  50
  51static int hsu_dma_enable;
  52module_param(hsu_dma_enable, int, 0);
  53MODULE_PARM_DESC(hsu_dma_enable,
  54		 "It is a bitmap to set working mode, if bit[x] is 1, then port[x] will work in DMA mode, otherwise in PIO mode.");
  55
  56struct hsu_dma_buffer {
  57	u8		*buf;
  58	dma_addr_t	dma_addr;
  59	u32		dma_size;
  60	u32		ofs;
  61};
  62
  63struct hsu_dma_chan {
  64	u32	id;
  65	enum dma_data_direction	dirt;
  66	struct uart_hsu_port	*uport;
  67	void __iomem		*reg;
  68};
  69
  70struct uart_hsu_port {
  71	struct uart_port        port;
  72	unsigned char           ier;
  73	unsigned char           lcr;
  74	unsigned char           mcr;
  75	unsigned int            lsr_break_flag;
  76	char			name[12];
  77	int			index;
  78	struct device		*dev;
  79
  80	struct hsu_dma_chan	*txc;
  81	struct hsu_dma_chan	*rxc;
  82	struct hsu_dma_buffer	txbuf;
  83	struct hsu_dma_buffer	rxbuf;
  84	int			use_dma;	/* flag for DMA/PIO */
  85	int			running;
  86	int			dma_tx_on;
  87};
  88
  89/* Top level data structure of HSU */
  90struct hsu_port {
  91	void __iomem	*reg;
  92	unsigned long	paddr;
  93	unsigned long	iolen;
  94	u32		irq;
  95
  96	struct uart_hsu_port	port[3];
  97	struct hsu_dma_chan	chans[10];
  98
  99	struct dentry *debugfs;
 100};
 101
 102static inline unsigned int serial_in(struct uart_hsu_port *up, int offset)
 103{
 104	unsigned int val;
 105
 106	if (offset > UART_MSR) {
 107		offset <<= 2;
 108		val = readl(up->port.membase + offset);
 109	} else
 110		val = (unsigned int)readb(up->port.membase + offset);
 111
 112	return val;
 113}
 114
 115static inline void serial_out(struct uart_hsu_port *up, int offset, int value)
 116{
 117	if (offset > UART_MSR) {
 118		offset <<= 2;
 119		writel(value, up->port.membase + offset);
 120	} else {
 121		unsigned char val = value & 0xff;
 122		writeb(val, up->port.membase + offset);
 123	}
 124}
 125
 126#ifdef CONFIG_DEBUG_FS
 127
 128#define HSU_REGS_BUFSIZE	1024
 129
 
 
 
 
 
 130
 131static ssize_t port_show_regs(struct file *file, char __user *user_buf,
 132				size_t count, loff_t *ppos)
 133{
 134	struct uart_hsu_port *up = file->private_data;
 135	char *buf;
 136	u32 len = 0;
 137	ssize_t ret;
 138
 139	buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL);
 140	if (!buf)
 141		return 0;
 142
 143	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 144			"MFD HSU port[%d] regs:\n", up->index);
 145
 146	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 147			"=================================\n");
 148	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 149			"IER: \t\t0x%08x\n", serial_in(up, UART_IER));
 150	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 151			"IIR: \t\t0x%08x\n", serial_in(up, UART_IIR));
 152	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 153			"LCR: \t\t0x%08x\n", serial_in(up, UART_LCR));
 154	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 155			"MCR: \t\t0x%08x\n", serial_in(up, UART_MCR));
 156	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 157			"LSR: \t\t0x%08x\n", serial_in(up, UART_LSR));
 158	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 159			"MSR: \t\t0x%08x\n", serial_in(up, UART_MSR));
 160	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 161			"FOR: \t\t0x%08x\n", serial_in(up, UART_FOR));
 162	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 163			"PS: \t\t0x%08x\n", serial_in(up, UART_PS));
 164	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 165			"MUL: \t\t0x%08x\n", serial_in(up, UART_MUL));
 166	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 167			"DIV: \t\t0x%08x\n", serial_in(up, UART_DIV));
 168
 169	if (len > HSU_REGS_BUFSIZE)
 170		len = HSU_REGS_BUFSIZE;
 171
 172	ret =  simple_read_from_buffer(user_buf, count, ppos, buf, len);
 173	kfree(buf);
 174	return ret;
 175}
 176
 177static ssize_t dma_show_regs(struct file *file, char __user *user_buf,
 178				size_t count, loff_t *ppos)
 179{
 180	struct hsu_dma_chan *chan = file->private_data;
 181	char *buf;
 182	u32 len = 0;
 183	ssize_t ret;
 184
 185	buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL);
 186	if (!buf)
 187		return 0;
 188
 189	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 190			"MFD HSU DMA channel [%d] regs:\n", chan->id);
 191
 192	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 193			"=================================\n");
 194	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 195			"CR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_CR));
 196	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 197			"DCR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_DCR));
 198	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 199			"BSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_BSR));
 200	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 201			"MOTSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_MOTSR));
 202	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 203			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0SAR));
 204	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 205			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0TSR));
 206	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 207			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1SAR));
 208	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 209			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1TSR));
 210	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 211			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2SAR));
 212	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 213			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2TSR));
 214	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 215			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3SAR));
 216	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
 217			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3TSR));
 218
 219	if (len > HSU_REGS_BUFSIZE)
 220		len = HSU_REGS_BUFSIZE;
 221
 222	ret =  simple_read_from_buffer(user_buf, count, ppos, buf, len);
 223	kfree(buf);
 224	return ret;
 225}
 226
 227static const struct file_operations port_regs_ops = {
 228	.owner		= THIS_MODULE,
 229	.open		= simple_open,
 230	.read		= port_show_regs,
 231	.llseek		= default_llseek,
 232};
 233
 234static const struct file_operations dma_regs_ops = {
 235	.owner		= THIS_MODULE,
 236	.open		= simple_open,
 237	.read		= dma_show_regs,
 238	.llseek		= default_llseek,
 239};
 240
 241static int hsu_debugfs_init(struct hsu_port *hsu)
 242{
 243	int i;
 244	char name[32];
 245
 246	hsu->debugfs = debugfs_create_dir("hsu", NULL);
 247	if (!hsu->debugfs)
 248		return -ENOMEM;
 249
 250	for (i = 0; i < 3; i++) {
 251		snprintf(name, sizeof(name), "port_%d_regs", i);
 252		debugfs_create_file(name, S_IFREG | S_IRUGO,
 253			hsu->debugfs, (void *)(&hsu->port[i]), &port_regs_ops);
 254	}
 255
 256	for (i = 0; i < 6; i++) {
 257		snprintf(name, sizeof(name), "dma_chan_%d_regs", i);
 258		debugfs_create_file(name, S_IFREG | S_IRUGO,
 259			hsu->debugfs, (void *)&hsu->chans[i], &dma_regs_ops);
 260	}
 261
 262	return 0;
 263}
 264
 265static void hsu_debugfs_remove(struct hsu_port *hsu)
 266{
 267	if (hsu->debugfs)
 268		debugfs_remove_recursive(hsu->debugfs);
 269}
 270
 271#else
 272static inline int hsu_debugfs_init(struct hsu_port *hsu)
 273{
 274	return 0;
 275}
 276
 277static inline void hsu_debugfs_remove(struct hsu_port *hsu)
 278{
 279}
 280#endif /* CONFIG_DEBUG_FS */
 281
 282static void serial_hsu_enable_ms(struct uart_port *port)
 283{
 284	struct uart_hsu_port *up =
 285		container_of(port, struct uart_hsu_port, port);
 286
 287	up->ier |= UART_IER_MSI;
 288	serial_out(up, UART_IER, up->ier);
 289}
 290
 291void hsu_dma_tx(struct uart_hsu_port *up)
 292{
 293	struct circ_buf *xmit = &up->port.state->xmit;
 294	struct hsu_dma_buffer *dbuf = &up->txbuf;
 295	int count;
 296
 297	/* test_and_set_bit may be better, but anyway it's in lock protected mode */
 298	if (up->dma_tx_on)
 299		return;
 300
 301	/* Update the circ buf info */
 302	xmit->tail += dbuf->ofs;
 303	xmit->tail &= UART_XMIT_SIZE - 1;
 304
 305	up->port.icount.tx += dbuf->ofs;
 306	dbuf->ofs = 0;
 307
 308	/* Disable the channel */
 309	chan_writel(up->txc, HSU_CH_CR, 0x0);
 310
 311	if (!uart_circ_empty(xmit) && !uart_tx_stopped(&up->port)) {
 312		dma_sync_single_for_device(up->port.dev,
 313					   dbuf->dma_addr,
 314					   dbuf->dma_size,
 315					   DMA_TO_DEVICE);
 316
 317		count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 318		dbuf->ofs = count;
 319
 320		/* Reprogram the channel */
 321		chan_writel(up->txc, HSU_CH_D0SAR, dbuf->dma_addr + xmit->tail);
 322		chan_writel(up->txc, HSU_CH_D0TSR, count);
 323
 324		/* Reenable the channel */
 325		chan_writel(up->txc, HSU_CH_DCR, 0x1
 326						 | (0x1 << 8)
 327						 | (0x1 << 16)
 328						 | (0x1 << 24));
 329		up->dma_tx_on = 1;
 330		chan_writel(up->txc, HSU_CH_CR, 0x1);
 331	}
 332
 333	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 334		uart_write_wakeup(&up->port);
 335}
 336
 337/* The buffer is already cache coherent */
 338void hsu_dma_start_rx_chan(struct hsu_dma_chan *rxc, struct hsu_dma_buffer *dbuf)
 339{
 340	dbuf->ofs = 0;
 341
 342	chan_writel(rxc, HSU_CH_BSR, 32);
 343	chan_writel(rxc, HSU_CH_MOTSR, 4);
 344
 345	chan_writel(rxc, HSU_CH_D0SAR, dbuf->dma_addr);
 346	chan_writel(rxc, HSU_CH_D0TSR, dbuf->dma_size);
 347	chan_writel(rxc, HSU_CH_DCR, 0x1 | (0x1 << 8)
 348					 | (0x1 << 16)
 349					 | (0x1 << 24)	/* timeout bit, see HSU Errata 1 */
 350					 );
 351	chan_writel(rxc, HSU_CH_CR, 0x3);
 352}
 353
 354/* Protected by spin_lock_irqsave(port->lock) */
 355static void serial_hsu_start_tx(struct uart_port *port)
 356{
 357	struct uart_hsu_port *up =
 358		container_of(port, struct uart_hsu_port, port);
 359
 360	if (up->use_dma) {
 361		hsu_dma_tx(up);
 362	} else if (!(up->ier & UART_IER_THRI)) {
 363		up->ier |= UART_IER_THRI;
 364		serial_out(up, UART_IER, up->ier);
 365	}
 366}
 367
 368static void serial_hsu_stop_tx(struct uart_port *port)
 369{
 370	struct uart_hsu_port *up =
 371		container_of(port, struct uart_hsu_port, port);
 372	struct hsu_dma_chan *txc = up->txc;
 373
 374	if (up->use_dma)
 375		chan_writel(txc, HSU_CH_CR, 0x0);
 376	else if (up->ier & UART_IER_THRI) {
 377		up->ier &= ~UART_IER_THRI;
 378		serial_out(up, UART_IER, up->ier);
 379	}
 380}
 381
 382/* This is always called in spinlock protected mode, so
 383 * modify timeout timer is safe here */
 384void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts)
 385{
 386	struct hsu_dma_buffer *dbuf = &up->rxbuf;
 387	struct hsu_dma_chan *chan = up->rxc;
 388	struct uart_port *port = &up->port;
 389	struct tty_struct *tty = port->state->port.tty;
 390	int count;
 391
 392	if (!tty)
 393		return;
 394
 395	/*
 396	 * First need to know how many is already transferred,
 397	 * then check if its a timeout DMA irq, and return
 398	 * the trail bytes out, push them up and reenable the
 399	 * channel
 400	 */
 401
 402	/* Timeout IRQ, need wait some time, see Errata 2 */
 403	if (int_sts & 0xf00)
 404		udelay(2);
 405
 406	/* Stop the channel */
 407	chan_writel(chan, HSU_CH_CR, 0x0);
 408
 409	count = chan_readl(chan, HSU_CH_D0SAR) - dbuf->dma_addr;
 410	if (!count) {
 411		/* Restart the channel before we leave */
 412		chan_writel(chan, HSU_CH_CR, 0x3);
 413		return;
 414	}
 415
 416	dma_sync_single_for_cpu(port->dev, dbuf->dma_addr,
 417			dbuf->dma_size, DMA_FROM_DEVICE);
 418
 419	/*
 420	 * Head will only wrap around when we recycle
 421	 * the DMA buffer, and when that happens, we
 422	 * explicitly set tail to 0. So head will
 423	 * always be greater than tail.
 424	 */
 425	tty_insert_flip_string(tty, dbuf->buf, count);
 426	port->icount.rx += count;
 427
 428	dma_sync_single_for_device(up->port.dev, dbuf->dma_addr,
 429			dbuf->dma_size, DMA_FROM_DEVICE);
 430
 431	/* Reprogram the channel */
 432	chan_writel(chan, HSU_CH_D0SAR, dbuf->dma_addr);
 433	chan_writel(chan, HSU_CH_D0TSR, dbuf->dma_size);
 434	chan_writel(chan, HSU_CH_DCR, 0x1
 435					 | (0x1 << 8)
 436					 | (0x1 << 16)
 437					 | (0x1 << 24)	/* timeout bit, see HSU Errata 1 */
 438					 );
 439	tty_flip_buffer_push(tty);
 440
 441	chan_writel(chan, HSU_CH_CR, 0x3);
 442
 443}
 444
 445static void serial_hsu_stop_rx(struct uart_port *port)
 446{
 447	struct uart_hsu_port *up =
 448		container_of(port, struct uart_hsu_port, port);
 449	struct hsu_dma_chan *chan = up->rxc;
 450
 451	if (up->use_dma)
 452		chan_writel(chan, HSU_CH_CR, 0x2);
 453	else {
 454		up->ier &= ~UART_IER_RLSI;
 455		up->port.read_status_mask &= ~UART_LSR_DR;
 456		serial_out(up, UART_IER, up->ier);
 457	}
 458}
 459
 460static inline void receive_chars(struct uart_hsu_port *up, int *status)
 461{
 462	struct tty_struct *tty = up->port.state->port.tty;
 463	unsigned int ch, flag;
 464	unsigned int max_count = 256;
 465
 466	if (!tty)
 467		return;
 468
 469	do {
 470		ch = serial_in(up, UART_RX);
 471		flag = TTY_NORMAL;
 472		up->port.icount.rx++;
 473
 474		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
 475				       UART_LSR_FE | UART_LSR_OE))) {
 476
 477			dev_warn(up->dev, "We really rush into ERR/BI case"
 478				"status = 0x%02x", *status);
 479			/* For statistics only */
 480			if (*status & UART_LSR_BI) {
 481				*status &= ~(UART_LSR_FE | UART_LSR_PE);
 482				up->port.icount.brk++;
 483				/*
 484				 * We do the SysRQ and SAK checking
 485				 * here because otherwise the break
 486				 * may get masked by ignore_status_mask
 487				 * or read_status_mask.
 488				 */
 489				if (uart_handle_break(&up->port))
 490					goto ignore_char;
 491			} else if (*status & UART_LSR_PE)
 492				up->port.icount.parity++;
 493			else if (*status & UART_LSR_FE)
 494				up->port.icount.frame++;
 495			if (*status & UART_LSR_OE)
 496				up->port.icount.overrun++;
 497
 498			/* Mask off conditions which should be ignored. */
 499			*status &= up->port.read_status_mask;
 500
 501#ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
 502			if (up->port.cons &&
 503				up->port.cons->index == up->port.line) {
 504				/* Recover the break flag from console xmit */
 505				*status |= up->lsr_break_flag;
 506				up->lsr_break_flag = 0;
 507			}
 508#endif
 509			if (*status & UART_LSR_BI) {
 510				flag = TTY_BREAK;
 511			} else if (*status & UART_LSR_PE)
 512				flag = TTY_PARITY;
 513			else if (*status & UART_LSR_FE)
 514				flag = TTY_FRAME;
 515		}
 516
 517		if (uart_handle_sysrq_char(&up->port, ch))
 518			goto ignore_char;
 519
 520		uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
 521	ignore_char:
 522		*status = serial_in(up, UART_LSR);
 523	} while ((*status & UART_LSR_DR) && max_count--);
 524	tty_flip_buffer_push(tty);
 525}
 526
 527static void transmit_chars(struct uart_hsu_port *up)
 528{
 529	struct circ_buf *xmit = &up->port.state->xmit;
 530	int count;
 531
 532	if (up->port.x_char) {
 533		serial_out(up, UART_TX, up->port.x_char);
 534		up->port.icount.tx++;
 535		up->port.x_char = 0;
 536		return;
 537	}
 538	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
 539		serial_hsu_stop_tx(&up->port);
 540		return;
 541	}
 542
 543	/* The IRQ is for TX FIFO half-empty */
 544	count = up->port.fifosize / 2;
 545
 546	do {
 547		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
 548		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 549
 550		up->port.icount.tx++;
 551		if (uart_circ_empty(xmit))
 552			break;
 553	} while (--count > 0);
 554
 555	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 556		uart_write_wakeup(&up->port);
 557
 558	if (uart_circ_empty(xmit))
 559		serial_hsu_stop_tx(&up->port);
 560}
 561
 562static inline void check_modem_status(struct uart_hsu_port *up)
 563{
 564	int status;
 565
 566	status = serial_in(up, UART_MSR);
 567
 568	if ((status & UART_MSR_ANY_DELTA) == 0)
 569		return;
 570
 571	if (status & UART_MSR_TERI)
 572		up->port.icount.rng++;
 573	if (status & UART_MSR_DDSR)
 574		up->port.icount.dsr++;
 575	/* We may only get DDCD when HW init and reset */
 576	if (status & UART_MSR_DDCD)
 577		uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
 578	/* Will start/stop_tx accordingly */
 579	if (status & UART_MSR_DCTS)
 580		uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
 581
 582	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
 583}
 584
 585/*
 586 * This handles the interrupt from one port.
 587 */
 588static irqreturn_t port_irq(int irq, void *dev_id)
 589{
 590	struct uart_hsu_port *up = dev_id;
 591	unsigned int iir, lsr;
 592	unsigned long flags;
 593
 594	if (unlikely(!up->running))
 595		return IRQ_NONE;
 596
 597	spin_lock_irqsave(&up->port.lock, flags);
 598	if (up->use_dma) {
 599		lsr = serial_in(up, UART_LSR);
 600		if (unlikely(lsr & (UART_LSR_BI | UART_LSR_PE |
 601				       UART_LSR_FE | UART_LSR_OE)))
 602			dev_warn(up->dev,
 603				"Got lsr irq while using DMA, lsr = 0x%2x\n",
 604				lsr);
 605		check_modem_status(up);
 606		spin_unlock_irqrestore(&up->port.lock, flags);
 607		return IRQ_HANDLED;
 608	}
 609
 610	iir = serial_in(up, UART_IIR);
 611	if (iir & UART_IIR_NO_INT) {
 612		spin_unlock_irqrestore(&up->port.lock, flags);
 613		return IRQ_NONE;
 614	}
 615
 616	lsr = serial_in(up, UART_LSR);
 617	if (lsr & UART_LSR_DR)
 618		receive_chars(up, &lsr);
 619	check_modem_status(up);
 620
 621	/* lsr will be renewed during the receive_chars */
 622	if (lsr & UART_LSR_THRE)
 623		transmit_chars(up);
 624
 625	spin_unlock_irqrestore(&up->port.lock, flags);
 626	return IRQ_HANDLED;
 627}
 628
 629static inline void dma_chan_irq(struct hsu_dma_chan *chan)
 630{
 631	struct uart_hsu_port *up = chan->uport;
 632	unsigned long flags;
 633	u32 int_sts;
 634
 635	spin_lock_irqsave(&up->port.lock, flags);
 636
 637	if (!up->use_dma || !up->running)
 638		goto exit;
 639
 640	/*
 641	 * No matter what situation, need read clear the IRQ status
 642	 * There is a bug, see Errata 5, HSD 2900918
 643	 */
 644	int_sts = chan_readl(chan, HSU_CH_SR);
 645
 646	/* Rx channel */
 647	if (chan->dirt == DMA_FROM_DEVICE)
 648		hsu_dma_rx(up, int_sts);
 649
 650	/* Tx channel */
 651	if (chan->dirt == DMA_TO_DEVICE) {
 652		chan_writel(chan, HSU_CH_CR, 0x0);
 653		up->dma_tx_on = 0;
 654		hsu_dma_tx(up);
 655	}
 656
 657exit:
 658	spin_unlock_irqrestore(&up->port.lock, flags);
 659	return;
 660}
 661
 662static irqreturn_t dma_irq(int irq, void *dev_id)
 663{
 664	struct hsu_port *hsu = dev_id;
 665	u32 int_sts, i;
 666
 667	int_sts = mfd_readl(hsu, HSU_GBL_DMAISR);
 668
 669	/* Currently we only have 6 channels may be used */
 670	for (i = 0; i < 6; i++) {
 671		if (int_sts & 0x1)
 672			dma_chan_irq(&hsu->chans[i]);
 673		int_sts >>= 1;
 674	}
 675
 676	return IRQ_HANDLED;
 677}
 678
 679static unsigned int serial_hsu_tx_empty(struct uart_port *port)
 680{
 681	struct uart_hsu_port *up =
 682		container_of(port, struct uart_hsu_port, port);
 683	unsigned long flags;
 684	unsigned int ret;
 685
 686	spin_lock_irqsave(&up->port.lock, flags);
 687	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
 688	spin_unlock_irqrestore(&up->port.lock, flags);
 689
 690	return ret;
 691}
 692
 693static unsigned int serial_hsu_get_mctrl(struct uart_port *port)
 694{
 695	struct uart_hsu_port *up =
 696		container_of(port, struct uart_hsu_port, port);
 697	unsigned char status;
 698	unsigned int ret;
 699
 700	status = serial_in(up, UART_MSR);
 701
 702	ret = 0;
 703	if (status & UART_MSR_DCD)
 704		ret |= TIOCM_CAR;
 705	if (status & UART_MSR_RI)
 706		ret |= TIOCM_RNG;
 707	if (status & UART_MSR_DSR)
 708		ret |= TIOCM_DSR;
 709	if (status & UART_MSR_CTS)
 710		ret |= TIOCM_CTS;
 711	return ret;
 712}
 713
 714static void serial_hsu_set_mctrl(struct uart_port *port, unsigned int mctrl)
 715{
 716	struct uart_hsu_port *up =
 717		container_of(port, struct uart_hsu_port, port);
 718	unsigned char mcr = 0;
 719
 720	if (mctrl & TIOCM_RTS)
 721		mcr |= UART_MCR_RTS;
 722	if (mctrl & TIOCM_DTR)
 723		mcr |= UART_MCR_DTR;
 724	if (mctrl & TIOCM_OUT1)
 725		mcr |= UART_MCR_OUT1;
 726	if (mctrl & TIOCM_OUT2)
 727		mcr |= UART_MCR_OUT2;
 728	if (mctrl & TIOCM_LOOP)
 729		mcr |= UART_MCR_LOOP;
 730
 731	mcr |= up->mcr;
 732
 733	serial_out(up, UART_MCR, mcr);
 734}
 735
 736static void serial_hsu_break_ctl(struct uart_port *port, int break_state)
 737{
 738	struct uart_hsu_port *up =
 739		container_of(port, struct uart_hsu_port, port);
 740	unsigned long flags;
 741
 742	spin_lock_irqsave(&up->port.lock, flags);
 743	if (break_state == -1)
 744		up->lcr |= UART_LCR_SBC;
 745	else
 746		up->lcr &= ~UART_LCR_SBC;
 747	serial_out(up, UART_LCR, up->lcr);
 748	spin_unlock_irqrestore(&up->port.lock, flags);
 749}
 750
 751/*
 752 * What special to do:
 753 * 1. chose the 64B fifo mode
 754 * 2. start dma or pio depends on configuration
 755 * 3. we only allocate dma memory when needed
 756 */
 757static int serial_hsu_startup(struct uart_port *port)
 758{
 759	struct uart_hsu_port *up =
 760		container_of(port, struct uart_hsu_port, port);
 761	unsigned long flags;
 762
 763	pm_runtime_get_sync(up->dev);
 764
 765	/*
 766	 * Clear the FIFO buffers and disable them.
 767	 * (they will be reenabled in set_termios())
 768	 */
 769	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
 770	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
 771			UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
 772	serial_out(up, UART_FCR, 0);
 773
 774	/* Clear the interrupt registers. */
 775	(void) serial_in(up, UART_LSR);
 776	(void) serial_in(up, UART_RX);
 777	(void) serial_in(up, UART_IIR);
 778	(void) serial_in(up, UART_MSR);
 779
 780	/* Now, initialize the UART, default is 8n1 */
 781	serial_out(up, UART_LCR, UART_LCR_WLEN8);
 782
 783	spin_lock_irqsave(&up->port.lock, flags);
 784
 785	up->port.mctrl |= TIOCM_OUT2;
 786	serial_hsu_set_mctrl(&up->port, up->port.mctrl);
 787
 788	/*
 789	 * Finally, enable interrupts.  Note: Modem status interrupts
 790	 * are set via set_termios(), which will be occurring imminently
 791	 * anyway, so we don't enable them here.
 792	 */
 793	if (!up->use_dma)
 794		up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE;
 795	else
 796		up->ier = 0;
 797	serial_out(up, UART_IER, up->ier);
 798
 799	spin_unlock_irqrestore(&up->port.lock, flags);
 800
 801	/* DMA init */
 802	if (up->use_dma) {
 803		struct hsu_dma_buffer *dbuf;
 804		struct circ_buf *xmit = &port->state->xmit;
 805
 806		up->dma_tx_on = 0;
 807
 808		/* First allocate the RX buffer */
 809		dbuf = &up->rxbuf;
 810		dbuf->buf = kzalloc(HSU_DMA_BUF_SIZE, GFP_KERNEL);
 811		if (!dbuf->buf) {
 812			up->use_dma = 0;
 813			goto exit;
 814		}
 815		dbuf->dma_addr = dma_map_single(port->dev,
 816						dbuf->buf,
 817						HSU_DMA_BUF_SIZE,
 818						DMA_FROM_DEVICE);
 819		dbuf->dma_size = HSU_DMA_BUF_SIZE;
 820
 821		/* Start the RX channel right now */
 822		hsu_dma_start_rx_chan(up->rxc, dbuf);
 823
 824		/* Next init the TX DMA */
 825		dbuf = &up->txbuf;
 826		dbuf->buf = xmit->buf;
 827		dbuf->dma_addr = dma_map_single(port->dev,
 828					       dbuf->buf,
 829					       UART_XMIT_SIZE,
 830					       DMA_TO_DEVICE);
 831		dbuf->dma_size = UART_XMIT_SIZE;
 832
 833		/* This should not be changed all around */
 834		chan_writel(up->txc, HSU_CH_BSR, 32);
 835		chan_writel(up->txc, HSU_CH_MOTSR, 4);
 836		dbuf->ofs = 0;
 837	}
 838
 839exit:
 840	 /* And clear the interrupt registers again for luck. */
 841	(void) serial_in(up, UART_LSR);
 842	(void) serial_in(up, UART_RX);
 843	(void) serial_in(up, UART_IIR);
 844	(void) serial_in(up, UART_MSR);
 845
 846	up->running = 1;
 847	return 0;
 848}
 849
 850static void serial_hsu_shutdown(struct uart_port *port)
 851{
 852	struct uart_hsu_port *up =
 853		container_of(port, struct uart_hsu_port, port);
 854	unsigned long flags;
 855
 856	/* Disable interrupts from this port */
 857	up->ier = 0;
 858	serial_out(up, UART_IER, 0);
 859	up->running = 0;
 860
 861	spin_lock_irqsave(&up->port.lock, flags);
 862	up->port.mctrl &= ~TIOCM_OUT2;
 863	serial_hsu_set_mctrl(&up->port, up->port.mctrl);
 864	spin_unlock_irqrestore(&up->port.lock, flags);
 865
 866	/* Disable break condition and FIFOs */
 867	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
 868	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
 869				  UART_FCR_CLEAR_RCVR |
 870				  UART_FCR_CLEAR_XMIT);
 871	serial_out(up, UART_FCR, 0);
 872
 873	pm_runtime_put(up->dev);
 874}
 875
 876static void
 877serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios,
 878		       struct ktermios *old)
 879{
 880	struct uart_hsu_port *up =
 881			container_of(port, struct uart_hsu_port, port);
 
 882	unsigned char cval, fcr = 0;
 883	unsigned long flags;
 884	unsigned int baud, quot;
 885	u32 ps, mul;
 886
 887	switch (termios->c_cflag & CSIZE) {
 888	case CS5:
 889		cval = UART_LCR_WLEN5;
 890		break;
 891	case CS6:
 892		cval = UART_LCR_WLEN6;
 893		break;
 894	case CS7:
 895		cval = UART_LCR_WLEN7;
 896		break;
 897	default:
 898	case CS8:
 899		cval = UART_LCR_WLEN8;
 900		break;
 901	}
 902
 903	/* CMSPAR isn't supported by this driver */
 904	termios->c_cflag &= ~CMSPAR;
 
 905
 906	if (termios->c_cflag & CSTOPB)
 907		cval |= UART_LCR_STOP;
 908	if (termios->c_cflag & PARENB)
 909		cval |= UART_LCR_PARITY;
 910	if (!(termios->c_cflag & PARODD))
 911		cval |= UART_LCR_EPAR;
 912
 913	/*
 914	 * The base clk is 50Mhz, and the baud rate come from:
 915	 *	baud = 50M * MUL / (DIV * PS * DLAB)
 916	 *
 917	 * For those basic low baud rate we can get the direct
 918	 * scalar from 2746800, like 115200 = 2746800/24. For those
 919	 * higher baud rate, we handle them case by case, mainly by
 920	 * adjusting the MUL/PS registers, and DIV register is kept
 921	 * as default value 0x3d09 to make things simple
 922	 */
 923	baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
 924
 925	quot = 1;
 926	ps = 0x10;
 927	mul = 0x3600;
 928	switch (baud) {
 929	case 3500000:
 930		mul = 0x3345;
 931		ps = 0xC;
 932		break;
 933	case 1843200:
 934		mul = 0x2400;
 935		break;
 936	case 3000000:
 937	case 2500000:
 938	case 2000000:
 939	case 1500000:
 940	case 1000000:
 941	case 500000:
 942		/* mul/ps/quot = 0x9C4/0x10/0x1 will make a 500000 bps */
 943		mul = baud / 500000 * 0x9C4;
 944		break;
 945	default:
 946		/* Use uart_get_divisor to get quot for other baud rates */
 947		quot = 0;
 948	}
 949
 950	if (!quot)
 951		quot = uart_get_divisor(port, baud);
 952
 953	if ((up->port.uartclk / quot) < (2400 * 16))
 954		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_1B;
 955	else if ((up->port.uartclk / quot) < (230400 * 16))
 956		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_16B;
 957	else
 958		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_32B;
 959
 960	fcr |= UART_FCR_HSU_64B_FIFO;
 961
 962	/*
 963	 * Ok, we're now changing the port state.  Do it with
 964	 * interrupts disabled.
 965	 */
 966	spin_lock_irqsave(&up->port.lock, flags);
 967
 968	/* Update the per-port timeout */
 969	uart_update_timeout(port, termios->c_cflag, baud);
 970
 971	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
 972	if (termios->c_iflag & INPCK)
 973		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
 974	if (termios->c_iflag & (BRKINT | PARMRK))
 975		up->port.read_status_mask |= UART_LSR_BI;
 976
 977	/* Characters to ignore */
 978	up->port.ignore_status_mask = 0;
 979	if (termios->c_iflag & IGNPAR)
 980		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 981	if (termios->c_iflag & IGNBRK) {
 982		up->port.ignore_status_mask |= UART_LSR_BI;
 983		/*
 984		 * If we're ignoring parity and break indicators,
 985		 * ignore overruns too (for real raw support).
 986		 */
 987		if (termios->c_iflag & IGNPAR)
 988			up->port.ignore_status_mask |= UART_LSR_OE;
 989	}
 990
 991	/* Ignore all characters if CREAD is not set */
 992	if ((termios->c_cflag & CREAD) == 0)
 993		up->port.ignore_status_mask |= UART_LSR_DR;
 994
 995	/*
 996	 * CTS flow control flag and modem status interrupts, disable
 997	 * MSI by default
 998	 */
 999	up->ier &= ~UART_IER_MSI;
1000	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
1001		up->ier |= UART_IER_MSI;
1002
1003	serial_out(up, UART_IER, up->ier);
1004
1005	if (termios->c_cflag & CRTSCTS)
1006		up->mcr |= UART_MCR_AFE | UART_MCR_RTS;
1007	else
1008		up->mcr &= ~UART_MCR_AFE;
1009
1010	serial_out(up, UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
1011	serial_out(up, UART_DLL, quot & 0xff);		/* LS of divisor */
1012	serial_out(up, UART_DLM, quot >> 8);		/* MS of divisor */
1013	serial_out(up, UART_LCR, cval);			/* reset DLAB */
1014	serial_out(up, UART_MUL, mul);			/* set MUL */
1015	serial_out(up, UART_PS, ps);			/* set PS */
1016	up->lcr = cval;					/* Save LCR */
1017	serial_hsu_set_mctrl(&up->port, up->port.mctrl);
1018	serial_out(up, UART_FCR, fcr);
1019	spin_unlock_irqrestore(&up->port.lock, flags);
1020}
1021
1022static void
1023serial_hsu_pm(struct uart_port *port, unsigned int state,
1024	      unsigned int oldstate)
1025{
1026}
1027
1028static void serial_hsu_release_port(struct uart_port *port)
1029{
1030}
1031
1032static int serial_hsu_request_port(struct uart_port *port)
1033{
1034	return 0;
1035}
1036
1037static void serial_hsu_config_port(struct uart_port *port, int flags)
1038{
1039	struct uart_hsu_port *up =
1040		container_of(port, struct uart_hsu_port, port);
1041	up->port.type = PORT_MFD;
1042}
1043
1044static int
1045serial_hsu_verify_port(struct uart_port *port, struct serial_struct *ser)
1046{
1047	/* We don't want the core code to modify any port params */
1048	return -EINVAL;
1049}
1050
1051static const char *
1052serial_hsu_type(struct uart_port *port)
1053{
1054	struct uart_hsu_port *up =
1055		container_of(port, struct uart_hsu_port, port);
1056	return up->name;
1057}
1058
1059/* Mainly for uart console use */
1060static struct uart_hsu_port *serial_hsu_ports[3];
1061static struct uart_driver serial_hsu_reg;
1062
1063#ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
1064
1065#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1066
1067/* Wait for transmitter & holding register to empty */
1068static inline void wait_for_xmitr(struct uart_hsu_port *up)
1069{
1070	unsigned int status, tmout = 1000;
1071
1072	/* Wait up to 1ms for the character to be sent. */
1073	do {
1074		status = serial_in(up, UART_LSR);
1075
1076		if (status & UART_LSR_BI)
1077			up->lsr_break_flag = UART_LSR_BI;
1078
1079		if (--tmout == 0)
1080			break;
1081		udelay(1);
1082	} while (!(status & BOTH_EMPTY));
1083
1084	/* Wait up to 1s for flow control if necessary */
1085	if (up->port.flags & UPF_CONS_FLOW) {
1086		tmout = 1000000;
1087		while (--tmout &&
1088		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
1089			udelay(1);
1090	}
1091}
1092
1093static void serial_hsu_console_putchar(struct uart_port *port, int ch)
1094{
1095	struct uart_hsu_port *up =
1096		container_of(port, struct uart_hsu_port, port);
1097
1098	wait_for_xmitr(up);
1099	serial_out(up, UART_TX, ch);
1100}
1101
1102/*
1103 * Print a string to the serial port trying not to disturb
1104 * any possible real use of the port...
1105 *
1106 *	The console_lock must be held when we get here.
1107 */
1108static void
1109serial_hsu_console_write(struct console *co, const char *s, unsigned int count)
1110{
1111	struct uart_hsu_port *up = serial_hsu_ports[co->index];
1112	unsigned long flags;
1113	unsigned int ier;
1114	int locked = 1;
1115
1116	local_irq_save(flags);
1117	if (up->port.sysrq)
1118		locked = 0;
1119	else if (oops_in_progress) {
1120		locked = spin_trylock(&up->port.lock);
1121	} else
1122		spin_lock(&up->port.lock);
1123
1124	/* First save the IER then disable the interrupts */
1125	ier = serial_in(up, UART_IER);
1126	serial_out(up, UART_IER, 0);
1127
1128	uart_console_write(&up->port, s, count, serial_hsu_console_putchar);
1129
1130	/*
1131	 * Finally, wait for transmitter to become empty
1132	 * and restore the IER
1133	 */
1134	wait_for_xmitr(up);
1135	serial_out(up, UART_IER, ier);
1136
1137	if (locked)
1138		spin_unlock(&up->port.lock);
1139	local_irq_restore(flags);
1140}
1141
1142static struct console serial_hsu_console;
1143
1144static int __init
1145serial_hsu_console_setup(struct console *co, char *options)
1146{
1147	struct uart_hsu_port *up;
1148	int baud = 115200;
1149	int bits = 8;
1150	int parity = 'n';
1151	int flow = 'n';
 
1152
1153	if (co->index == -1 || co->index >= serial_hsu_reg.nr)
1154		co->index = 0;
1155	up = serial_hsu_ports[co->index];
1156	if (!up)
1157		return -ENODEV;
1158
1159	if (options)
1160		uart_parse_options(options, &baud, &parity, &bits, &flow);
1161
1162	return uart_set_options(&up->port, co, baud, parity, bits, flow);
 
 
1163}
1164
1165static struct console serial_hsu_console = {
1166	.name		= "ttyMFD",
1167	.write		= serial_hsu_console_write,
1168	.device		= uart_console_device,
1169	.setup		= serial_hsu_console_setup,
1170	.flags		= CON_PRINTBUFFER,
1171	.index		= -1,
1172	.data		= &serial_hsu_reg,
1173};
1174
1175#define SERIAL_HSU_CONSOLE	(&serial_hsu_console)
1176#else
1177#define SERIAL_HSU_CONSOLE	NULL
1178#endif
1179
1180struct uart_ops serial_hsu_pops = {
1181	.tx_empty	= serial_hsu_tx_empty,
1182	.set_mctrl	= serial_hsu_set_mctrl,
1183	.get_mctrl	= serial_hsu_get_mctrl,
1184	.stop_tx	= serial_hsu_stop_tx,
1185	.start_tx	= serial_hsu_start_tx,
1186	.stop_rx	= serial_hsu_stop_rx,
1187	.enable_ms	= serial_hsu_enable_ms,
1188	.break_ctl	= serial_hsu_break_ctl,
1189	.startup	= serial_hsu_startup,
1190	.shutdown	= serial_hsu_shutdown,
1191	.set_termios	= serial_hsu_set_termios,
1192	.pm		= serial_hsu_pm,
1193	.type		= serial_hsu_type,
1194	.release_port	= serial_hsu_release_port,
1195	.request_port	= serial_hsu_request_port,
1196	.config_port	= serial_hsu_config_port,
1197	.verify_port	= serial_hsu_verify_port,
1198};
1199
1200static struct uart_driver serial_hsu_reg = {
1201	.owner		= THIS_MODULE,
1202	.driver_name	= "MFD serial",
1203	.dev_name	= "ttyMFD",
1204	.major		= TTY_MAJOR,
1205	.minor		= 128,
1206	.nr		= 3,
1207	.cons		= SERIAL_HSU_CONSOLE,
1208};
1209
1210#ifdef CONFIG_PM
1211static int serial_hsu_suspend(struct pci_dev *pdev, pm_message_t state)
1212{
1213	void *priv = pci_get_drvdata(pdev);
1214	struct uart_hsu_port *up;
1215
1216	/* Make sure this is not the internal dma controller */
1217	if (priv && (pdev->device != 0x081E)) {
1218		up = priv;
1219		uart_suspend_port(&serial_hsu_reg, &up->port);
1220	}
1221
1222	pci_save_state(pdev);
1223	pci_set_power_state(pdev, pci_choose_state(pdev, state));
1224        return 0;
1225}
1226
1227static int serial_hsu_resume(struct pci_dev *pdev)
1228{
1229	void *priv = pci_get_drvdata(pdev);
1230	struct uart_hsu_port *up;
1231	int ret;
1232
1233	pci_set_power_state(pdev, PCI_D0);
1234	pci_restore_state(pdev);
1235
1236	ret = pci_enable_device(pdev);
1237	if (ret)
1238		dev_warn(&pdev->dev,
1239			"HSU: can't re-enable device, try to continue\n");
1240
1241	if (priv && (pdev->device != 0x081E)) {
1242		up = priv;
1243		uart_resume_port(&serial_hsu_reg, &up->port);
1244	}
1245	return 0;
1246}
1247#else
1248#define serial_hsu_suspend	NULL
1249#define serial_hsu_resume	NULL
1250#endif
1251
1252#ifdef CONFIG_PM_RUNTIME
1253static int serial_hsu_runtime_idle(struct device *dev)
1254{
1255	int err;
1256
1257	err = pm_schedule_suspend(dev, 500);
1258	if (err)
1259		return -EBUSY;
1260
1261	return 0;
1262}
1263
1264static int serial_hsu_runtime_suspend(struct device *dev)
1265{
1266	return 0;
1267}
1268
1269static int serial_hsu_runtime_resume(struct device *dev)
1270{
1271	return 0;
1272}
1273#else
1274#define serial_hsu_runtime_idle		NULL
1275#define serial_hsu_runtime_suspend	NULL
1276#define serial_hsu_runtime_resume	NULL
1277#endif
1278
1279static const struct dev_pm_ops serial_hsu_pm_ops = {
1280	.runtime_suspend = serial_hsu_runtime_suspend,
1281	.runtime_resume = serial_hsu_runtime_resume,
1282	.runtime_idle = serial_hsu_runtime_idle,
1283};
1284
1285/* temp global pointer before we settle down on using one or four PCI dev */
1286static struct hsu_port *phsu;
1287
1288static int serial_hsu_probe(struct pci_dev *pdev,
1289				const struct pci_device_id *ent)
1290{
1291	struct uart_hsu_port *uport;
1292	int index, ret;
1293
1294	printk(KERN_INFO "HSU: found PCI Serial controller(ID: %04x:%04x)\n",
1295		pdev->vendor, pdev->device);
1296
1297	switch (pdev->device) {
1298	case 0x081B:
1299		index = 0;
1300		break;
1301	case 0x081C:
1302		index = 1;
1303		break;
1304	case 0x081D:
1305		index = 2;
1306		break;
1307	case 0x081E:
1308		/* internal DMA controller */
1309		index = 3;
1310		break;
1311	default:
1312		dev_err(&pdev->dev, "HSU: out of index!");
1313		return -ENODEV;
1314	}
1315
1316	ret = pci_enable_device(pdev);
1317	if (ret)
1318		return ret;
1319
1320	if (index == 3) {
1321		/* DMA controller */
1322		ret = request_irq(pdev->irq, dma_irq, 0, "hsu_dma", phsu);
1323		if (ret) {
1324			dev_err(&pdev->dev, "can not get IRQ\n");
1325			goto err_disable;
1326		}
1327		pci_set_drvdata(pdev, phsu);
1328	} else {
1329		/* UART port 0~2 */
1330		uport = &phsu->port[index];
1331		uport->port.irq = pdev->irq;
1332		uport->port.dev = &pdev->dev;
1333		uport->dev = &pdev->dev;
1334
1335		ret = request_irq(pdev->irq, port_irq, 0, uport->name, uport);
1336		if (ret) {
1337			dev_err(&pdev->dev, "can not get IRQ\n");
1338			goto err_disable;
1339		}
1340		uart_add_one_port(&serial_hsu_reg, &uport->port);
1341
 
 
 
 
 
 
1342		pci_set_drvdata(pdev, uport);
1343	}
1344
1345	pm_runtime_put_noidle(&pdev->dev);
1346	pm_runtime_allow(&pdev->dev);
1347
1348	return 0;
1349
1350err_disable:
1351	pci_disable_device(pdev);
1352	return ret;
1353}
1354
1355static void hsu_global_init(void)
1356{
1357	struct hsu_port *hsu;
1358	struct uart_hsu_port *uport;
1359	struct hsu_dma_chan *dchan;
1360	int i, ret;
1361
1362	hsu = kzalloc(sizeof(struct hsu_port), GFP_KERNEL);
1363	if (!hsu)
1364		return;
1365
1366	/* Get basic io resource and map it */
1367	hsu->paddr = 0xffa28000;
1368	hsu->iolen = 0x1000;
1369
1370	if (!(request_mem_region(hsu->paddr, hsu->iolen, "HSU global")))
1371		pr_warning("HSU: error in request mem region\n");
1372
1373	hsu->reg = ioremap_nocache((unsigned long)hsu->paddr, hsu->iolen);
1374	if (!hsu->reg) {
1375		pr_err("HSU: error in ioremap\n");
1376		ret = -ENOMEM;
1377		goto err_free_region;
1378	}
1379
1380	/* Initialise the 3 UART ports */
1381	uport = hsu->port;
1382	for (i = 0; i < 3; i++) {
1383		uport->port.type = PORT_MFD;
1384		uport->port.iotype = UPIO_MEM;
1385		uport->port.mapbase = (resource_size_t)hsu->paddr
1386					+ HSU_PORT_REG_OFFSET
1387					+ i * HSU_PORT_REG_LENGTH;
1388		uport->port.membase = hsu->reg + HSU_PORT_REG_OFFSET
1389					+ i * HSU_PORT_REG_LENGTH;
1390
1391		sprintf(uport->name, "hsu_port%d", i);
1392		uport->port.fifosize = 64;
1393		uport->port.ops = &serial_hsu_pops;
1394		uport->port.line = i;
1395		uport->port.flags = UPF_IOREMAP;
1396		/* set the scalable maxim support rate to 2746800 bps */
1397		uport->port.uartclk = 115200 * 24 * 16;
1398
1399		uport->running = 0;
1400		uport->txc = &hsu->chans[i * 2];
1401		uport->rxc = &hsu->chans[i * 2 + 1];
1402
1403		serial_hsu_ports[i] = uport;
1404		uport->index = i;
1405
1406		if (hsu_dma_enable & (1<<i))
1407			uport->use_dma = 1;
1408		else
1409			uport->use_dma = 0;
1410
1411		uport++;
1412	}
1413
1414	/* Initialise 6 dma channels */
1415	dchan = hsu->chans;
1416	for (i = 0; i < 6; i++) {
1417		dchan->id = i;
1418		dchan->dirt = (i & 0x1) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1419		dchan->uport = &hsu->port[i/2];
1420		dchan->reg = hsu->reg + HSU_DMA_CHANS_REG_OFFSET +
1421				i * HSU_DMA_CHANS_REG_LENGTH;
1422
1423		dchan++;
1424	}
1425
1426	phsu = hsu;
1427	hsu_debugfs_init(hsu);
1428	return;
1429
1430err_free_region:
1431	release_mem_region(hsu->paddr, hsu->iolen);
1432	kfree(hsu);
1433	return;
1434}
1435
1436static void serial_hsu_remove(struct pci_dev *pdev)
1437{
1438	void *priv = pci_get_drvdata(pdev);
1439	struct uart_hsu_port *up;
1440
1441	if (!priv)
1442		return;
1443
1444	pm_runtime_forbid(&pdev->dev);
1445	pm_runtime_get_noresume(&pdev->dev);
1446
1447	/* For port 0/1/2, priv is the address of uart_hsu_port */
1448	if (pdev->device != 0x081E) {
1449		up = priv;
1450		uart_remove_one_port(&serial_hsu_reg, &up->port);
1451	}
1452
1453	pci_set_drvdata(pdev, NULL);
1454	free_irq(pdev->irq, priv);
1455	pci_disable_device(pdev);
1456}
1457
1458/* First 3 are UART ports, and the 4th is the DMA */
1459static const struct pci_device_id pci_ids[] __devinitconst = {
1460	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081B) },
1461	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081C) },
1462	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081D) },
1463	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081E) },
1464	{},
1465};
1466
1467static struct pci_driver hsu_pci_driver = {
1468	.name =		"HSU serial",
1469	.id_table =	pci_ids,
1470	.probe =	serial_hsu_probe,
1471	.remove =	__devexit_p(serial_hsu_remove),
1472	.suspend =	serial_hsu_suspend,
1473	.resume	=	serial_hsu_resume,
1474	.driver = {
1475		.pm = &serial_hsu_pm_ops,
1476	},
1477};
1478
1479static int __init hsu_pci_init(void)
1480{
1481	int ret;
1482
1483	hsu_global_init();
1484
1485	ret = uart_register_driver(&serial_hsu_reg);
1486	if (ret)
1487		return ret;
1488
1489	return pci_register_driver(&hsu_pci_driver);
1490}
1491
1492static void __exit hsu_pci_exit(void)
1493{
1494	pci_unregister_driver(&hsu_pci_driver);
1495	uart_unregister_driver(&serial_hsu_reg);
1496
1497	hsu_debugfs_remove(phsu);
1498
1499	kfree(phsu);
1500}
1501
1502module_init(hsu_pci_init);
1503module_exit(hsu_pci_exit);
1504
1505MODULE_LICENSE("GPL v2");
1506MODULE_ALIAS("platform:medfield-hsu");