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v5.14.15
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Driver for msm7k serial device and console
   4 *
   5 * Copyright (C) 2007 Google, Inc.
   6 * Author: Robert Love <rlove@google.com>
   7 * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
 
 
 
 
 
 
 
 
 
   8 */
   9
  10#include <linux/kernel.h>
 
 
 
  11#include <linux/atomic.h>
  12#include <linux/dma-mapping.h>
  13#include <linux/dmaengine.h>
  14#include <linux/module.h>
  15#include <linux/io.h>
  16#include <linux/ioport.h>
  17#include <linux/interrupt.h>
  18#include <linux/init.h>
  19#include <linux/console.h>
  20#include <linux/tty.h>
  21#include <linux/tty_flip.h>
  22#include <linux/serial_core.h>
  23#include <linux/slab.h>
  24#include <linux/clk.h>
  25#include <linux/platform_device.h>
  26#include <linux/delay.h>
  27#include <linux/of.h>
  28#include <linux/of_device.h>
  29#include <linux/wait.h>
  30
  31#define UART_MR1			0x0000
  32
  33#define UART_MR1_AUTO_RFR_LEVEL0	0x3F
  34#define UART_MR1_AUTO_RFR_LEVEL1	0x3FF00
  35#define UART_DM_MR1_AUTO_RFR_LEVEL1	0xFFFFFF00
  36#define UART_MR1_RX_RDY_CTL		BIT(7)
  37#define UART_MR1_CTS_CTL		BIT(6)
  38
  39#define UART_MR2			0x0004
  40#define UART_MR2_ERROR_MODE		BIT(6)
  41#define UART_MR2_BITS_PER_CHAR		0x30
  42#define UART_MR2_BITS_PER_CHAR_5	(0x0 << 4)
  43#define UART_MR2_BITS_PER_CHAR_6	(0x1 << 4)
  44#define UART_MR2_BITS_PER_CHAR_7	(0x2 << 4)
  45#define UART_MR2_BITS_PER_CHAR_8	(0x3 << 4)
  46#define UART_MR2_STOP_BIT_LEN_ONE	(0x1 << 2)
  47#define UART_MR2_STOP_BIT_LEN_TWO	(0x3 << 2)
  48#define UART_MR2_PARITY_MODE_NONE	0x0
  49#define UART_MR2_PARITY_MODE_ODD	0x1
  50#define UART_MR2_PARITY_MODE_EVEN	0x2
  51#define UART_MR2_PARITY_MODE_SPACE	0x3
  52#define UART_MR2_PARITY_MODE		0x3
  53
  54#define UART_CSR			0x0008
  55
  56#define UART_TF				0x000C
  57#define UARTDM_TF			0x0070
  58
  59#define UART_CR				0x0010
  60#define UART_CR_CMD_NULL		(0 << 4)
  61#define UART_CR_CMD_RESET_RX		(1 << 4)
  62#define UART_CR_CMD_RESET_TX		(2 << 4)
  63#define UART_CR_CMD_RESET_ERR		(3 << 4)
  64#define UART_CR_CMD_RESET_BREAK_INT	(4 << 4)
  65#define UART_CR_CMD_START_BREAK		(5 << 4)
  66#define UART_CR_CMD_STOP_BREAK		(6 << 4)
  67#define UART_CR_CMD_RESET_CTS		(7 << 4)
  68#define UART_CR_CMD_RESET_STALE_INT	(8 << 4)
  69#define UART_CR_CMD_PACKET_MODE		(9 << 4)
  70#define UART_CR_CMD_MODE_RESET		(12 << 4)
  71#define UART_CR_CMD_SET_RFR		(13 << 4)
  72#define UART_CR_CMD_RESET_RFR		(14 << 4)
  73#define UART_CR_CMD_PROTECTION_EN	(16 << 4)
  74#define UART_CR_CMD_STALE_EVENT_DISABLE	(6 << 8)
  75#define UART_CR_CMD_STALE_EVENT_ENABLE	(80 << 4)
  76#define UART_CR_CMD_FORCE_STALE		(4 << 8)
  77#define UART_CR_CMD_RESET_TX_READY	(3 << 8)
  78#define UART_CR_TX_DISABLE		BIT(3)
  79#define UART_CR_TX_ENABLE		BIT(2)
  80#define UART_CR_RX_DISABLE		BIT(1)
  81#define UART_CR_RX_ENABLE		BIT(0)
  82#define UART_CR_CMD_RESET_RXBREAK_START	((1 << 11) | (2 << 4))
  83
  84#define UART_IMR			0x0014
  85#define UART_IMR_TXLEV			BIT(0)
  86#define UART_IMR_RXSTALE		BIT(3)
  87#define UART_IMR_RXLEV			BIT(4)
  88#define UART_IMR_DELTA_CTS		BIT(5)
  89#define UART_IMR_CURRENT_CTS		BIT(6)
  90#define UART_IMR_RXBREAK_START		BIT(10)
  91
  92#define UART_IPR_RXSTALE_LAST		0x20
  93#define UART_IPR_STALE_LSB		0x1F
  94#define UART_IPR_STALE_TIMEOUT_MSB	0x3FF80
  95#define UART_DM_IPR_STALE_TIMEOUT_MSB	0xFFFFFF80
  96
  97#define UART_IPR			0x0018
  98#define UART_TFWR			0x001C
  99#define UART_RFWR			0x0020
 100#define UART_HCR			0x0024
 101
 102#define UART_MREG			0x0028
 103#define UART_NREG			0x002C
 104#define UART_DREG			0x0030
 105#define UART_MNDREG			0x0034
 106#define UART_IRDA			0x0038
 107#define UART_MISR_MODE			0x0040
 108#define UART_MISR_RESET			0x0044
 109#define UART_MISR_EXPORT		0x0048
 110#define UART_MISR_VAL			0x004C
 111#define UART_TEST_CTRL			0x0050
 112
 113#define UART_SR				0x0008
 114#define UART_SR_HUNT_CHAR		BIT(7)
 115#define UART_SR_RX_BREAK		BIT(6)
 116#define UART_SR_PAR_FRAME_ERR		BIT(5)
 117#define UART_SR_OVERRUN			BIT(4)
 118#define UART_SR_TX_EMPTY		BIT(3)
 119#define UART_SR_TX_READY		BIT(2)
 120#define UART_SR_RX_FULL			BIT(1)
 121#define UART_SR_RX_READY		BIT(0)
 122
 123#define UART_RF				0x000C
 124#define UARTDM_RF			0x0070
 125#define UART_MISR			0x0010
 126#define UART_ISR			0x0014
 127#define UART_ISR_TX_READY		BIT(7)
 128
 129#define UARTDM_RXFS			0x50
 130#define UARTDM_RXFS_BUF_SHIFT		0x7
 131#define UARTDM_RXFS_BUF_MASK		0x7
 132
 133#define UARTDM_DMEN			0x3C
 134#define UARTDM_DMEN_RX_SC_ENABLE	BIT(5)
 135#define UARTDM_DMEN_TX_SC_ENABLE	BIT(4)
 136
 137#define UARTDM_DMEN_TX_BAM_ENABLE	BIT(2)	/* UARTDM_1P4 */
 138#define UARTDM_DMEN_TX_DM_ENABLE	BIT(0)	/* < UARTDM_1P4 */
 139
 140#define UARTDM_DMEN_RX_BAM_ENABLE	BIT(3)	/* UARTDM_1P4 */
 141#define UARTDM_DMEN_RX_DM_ENABLE	BIT(1)	/* < UARTDM_1P4 */
 142
 143#define UARTDM_DMRX			0x34
 144#define UARTDM_NCF_TX			0x40
 145#define UARTDM_RX_TOTAL_SNAP		0x38
 146
 147#define UARTDM_BURST_SIZE		16   /* in bytes */
 148#define UARTDM_TX_AIGN(x)		((x) & ~0x3) /* valid for > 1p3 */
 149#define UARTDM_TX_MAX			256   /* in bytes, valid for <= 1p3 */
 150#define UARTDM_RX_SIZE			(UART_XMIT_SIZE / 4)
 151
 152enum {
 153	UARTDM_1P1 = 1,
 154	UARTDM_1P2,
 155	UARTDM_1P3,
 156	UARTDM_1P4,
 157};
 158
 159struct msm_dma {
 160	struct dma_chan		*chan;
 161	enum dma_data_direction dir;
 162	dma_addr_t		phys;
 163	unsigned char		*virt;
 164	dma_cookie_t		cookie;
 165	u32			enable_bit;
 166	unsigned int		count;
 167	struct dma_async_tx_descriptor	*desc;
 168};
 169
 170struct msm_port {
 171	struct uart_port	uart;
 172	char			name[16];
 173	struct clk		*clk;
 174	struct clk		*pclk;
 175	unsigned int		imr;
 
 176	int			is_uartdm;
 177	unsigned int		old_snap_state;
 178	bool			break_detected;
 179	struct msm_dma		tx_dma;
 180	struct msm_dma		rx_dma;
 181};
 182
 183#define UART_TO_MSM(uart_port)	container_of(uart_port, struct msm_port, uart)
 184
 185static
 186void msm_write(struct uart_port *port, unsigned int val, unsigned int off)
 187{
 188	writel_relaxed(val, port->membase + off);
 189}
 190
 191static
 192unsigned int msm_read(struct uart_port *port, unsigned int off)
 193{
 194	return readl_relaxed(port->membase + off);
 195}
 196
 197/*
 198 * Setup the MND registers to use the TCXO clock.
 199 */
 200static void msm_serial_set_mnd_regs_tcxo(struct uart_port *port)
 201{
 202	msm_write(port, 0x06, UART_MREG);
 203	msm_write(port, 0xF1, UART_NREG);
 204	msm_write(port, 0x0F, UART_DREG);
 205	msm_write(port, 0x1A, UART_MNDREG);
 206	port->uartclk = 1843200;
 207}
 208
 209/*
 210 * Setup the MND registers to use the TCXO clock divided by 4.
 211 */
 212static void msm_serial_set_mnd_regs_tcxoby4(struct uart_port *port)
 213{
 214	msm_write(port, 0x18, UART_MREG);
 215	msm_write(port, 0xF6, UART_NREG);
 216	msm_write(port, 0x0F, UART_DREG);
 217	msm_write(port, 0x0A, UART_MNDREG);
 218	port->uartclk = 1843200;
 219}
 220
 221static void msm_serial_set_mnd_regs(struct uart_port *port)
 222{
 223	struct msm_port *msm_port = UART_TO_MSM(port);
 224
 225	/*
 226	 * These registers don't exist so we change the clk input rate
 227	 * on uartdm hardware instead
 228	 */
 229	if (msm_port->is_uartdm)
 230		return;
 231
 232	if (port->uartclk == 19200000)
 233		msm_serial_set_mnd_regs_tcxo(port);
 234	else if (port->uartclk == 4800000)
 235		msm_serial_set_mnd_regs_tcxoby4(port);
 236}
 237
 238static void msm_handle_tx(struct uart_port *port);
 239static void msm_start_rx_dma(struct msm_port *msm_port);
 240
 241static void msm_stop_dma(struct uart_port *port, struct msm_dma *dma)
 242{
 243	struct device *dev = port->dev;
 244	unsigned int mapped;
 245	u32 val;
 246
 247	mapped = dma->count;
 248	dma->count = 0;
 249
 250	dmaengine_terminate_all(dma->chan);
 251
 252	/*
 253	 * DMA Stall happens if enqueue and flush command happens concurrently.
 254	 * For example before changing the baud rate/protocol configuration and
 255	 * sending flush command to ADM, disable the channel of UARTDM.
 256	 * Note: should not reset the receiver here immediately as it is not
 257	 * suggested to do disable/reset or reset/disable at the same time.
 258	 */
 259	val = msm_read(port, UARTDM_DMEN);
 260	val &= ~dma->enable_bit;
 261	msm_write(port, val, UARTDM_DMEN);
 262
 263	if (mapped)
 264		dma_unmap_single(dev, dma->phys, mapped, dma->dir);
 265}
 266
 267static void msm_release_dma(struct msm_port *msm_port)
 268{
 269	struct msm_dma *dma;
 270
 271	dma = &msm_port->tx_dma;
 272	if (dma->chan) {
 273		msm_stop_dma(&msm_port->uart, dma);
 274		dma_release_channel(dma->chan);
 275	}
 276
 277	memset(dma, 0, sizeof(*dma));
 278
 279	dma = &msm_port->rx_dma;
 280	if (dma->chan) {
 281		msm_stop_dma(&msm_port->uart, dma);
 282		dma_release_channel(dma->chan);
 283		kfree(dma->virt);
 284	}
 285
 286	memset(dma, 0, sizeof(*dma));
 287}
 288
 289static void msm_request_tx_dma(struct msm_port *msm_port, resource_size_t base)
 290{
 291	struct device *dev = msm_port->uart.dev;
 292	struct dma_slave_config conf;
 293	struct msm_dma *dma;
 294	u32 crci = 0;
 295	int ret;
 296
 297	dma = &msm_port->tx_dma;
 298
 299	/* allocate DMA resources, if available */
 300	dma->chan = dma_request_chan(dev, "tx");
 301	if (IS_ERR(dma->chan))
 302		goto no_tx;
 303
 304	of_property_read_u32(dev->of_node, "qcom,tx-crci", &crci);
 305
 306	memset(&conf, 0, sizeof(conf));
 307	conf.direction = DMA_MEM_TO_DEV;
 308	conf.device_fc = true;
 309	conf.dst_addr = base + UARTDM_TF;
 310	conf.dst_maxburst = UARTDM_BURST_SIZE;
 311	conf.slave_id = crci;
 312
 313	ret = dmaengine_slave_config(dma->chan, &conf);
 314	if (ret)
 315		goto rel_tx;
 316
 317	dma->dir = DMA_TO_DEVICE;
 318
 319	if (msm_port->is_uartdm < UARTDM_1P4)
 320		dma->enable_bit = UARTDM_DMEN_TX_DM_ENABLE;
 321	else
 322		dma->enable_bit = UARTDM_DMEN_TX_BAM_ENABLE;
 323
 324	return;
 325
 326rel_tx:
 327	dma_release_channel(dma->chan);
 328no_tx:
 329	memset(dma, 0, sizeof(*dma));
 330}
 331
 332static void msm_request_rx_dma(struct msm_port *msm_port, resource_size_t base)
 333{
 334	struct device *dev = msm_port->uart.dev;
 335	struct dma_slave_config conf;
 336	struct msm_dma *dma;
 337	u32 crci = 0;
 338	int ret;
 339
 340	dma = &msm_port->rx_dma;
 341
 342	/* allocate DMA resources, if available */
 343	dma->chan = dma_request_chan(dev, "rx");
 344	if (IS_ERR(dma->chan))
 345		goto no_rx;
 346
 347	of_property_read_u32(dev->of_node, "qcom,rx-crci", &crci);
 348
 349	dma->virt = kzalloc(UARTDM_RX_SIZE, GFP_KERNEL);
 350	if (!dma->virt)
 351		goto rel_rx;
 352
 353	memset(&conf, 0, sizeof(conf));
 354	conf.direction = DMA_DEV_TO_MEM;
 355	conf.device_fc = true;
 356	conf.src_addr = base + UARTDM_RF;
 357	conf.src_maxburst = UARTDM_BURST_SIZE;
 358	conf.slave_id = crci;
 359
 360	ret = dmaengine_slave_config(dma->chan, &conf);
 361	if (ret)
 362		goto err;
 363
 364	dma->dir = DMA_FROM_DEVICE;
 365
 366	if (msm_port->is_uartdm < UARTDM_1P4)
 367		dma->enable_bit = UARTDM_DMEN_RX_DM_ENABLE;
 368	else
 369		dma->enable_bit = UARTDM_DMEN_RX_BAM_ENABLE;
 370
 371	return;
 372err:
 373	kfree(dma->virt);
 374rel_rx:
 375	dma_release_channel(dma->chan);
 376no_rx:
 377	memset(dma, 0, sizeof(*dma));
 378}
 379
 380static inline void msm_wait_for_xmitr(struct uart_port *port)
 381{
 382	unsigned int timeout = 500000;
 383
 384	while (!(msm_read(port, UART_SR) & UART_SR_TX_EMPTY)) {
 385		if (msm_read(port, UART_ISR) & UART_ISR_TX_READY)
 386			break;
 387		udelay(1);
 388		if (!timeout--)
 389			break;
 390	}
 391	msm_write(port, UART_CR_CMD_RESET_TX_READY, UART_CR);
 392}
 393
 394static void msm_stop_tx(struct uart_port *port)
 395{
 396	struct msm_port *msm_port = UART_TO_MSM(port);
 397
 398	msm_port->imr &= ~UART_IMR_TXLEV;
 399	msm_write(port, msm_port->imr, UART_IMR);
 400}
 401
 402static void msm_start_tx(struct uart_port *port)
 403{
 404	struct msm_port *msm_port = UART_TO_MSM(port);
 405	struct msm_dma *dma = &msm_port->tx_dma;
 406
 407	/* Already started in DMA mode */
 408	if (dma->count)
 409		return;
 410
 411	msm_port->imr |= UART_IMR_TXLEV;
 412	msm_write(port, msm_port->imr, UART_IMR);
 413}
 414
 415static void msm_reset_dm_count(struct uart_port *port, int count)
 416{
 417	msm_wait_for_xmitr(port);
 418	msm_write(port, count, UARTDM_NCF_TX);
 419	msm_read(port, UARTDM_NCF_TX);
 420}
 421
 422static void msm_complete_tx_dma(void *args)
 423{
 424	struct msm_port *msm_port = args;
 425	struct uart_port *port = &msm_port->uart;
 426	struct circ_buf *xmit = &port->state->xmit;
 427	struct msm_dma *dma = &msm_port->tx_dma;
 428	struct dma_tx_state state;
 429	unsigned long flags;
 430	unsigned int count;
 431	u32 val;
 432
 433	spin_lock_irqsave(&port->lock, flags);
 434
 435	/* Already stopped */
 436	if (!dma->count)
 437		goto done;
 438
 439	dmaengine_tx_status(dma->chan, dma->cookie, &state);
 440
 441	dma_unmap_single(port->dev, dma->phys, dma->count, dma->dir);
 442
 443	val = msm_read(port, UARTDM_DMEN);
 444	val &= ~dma->enable_bit;
 445	msm_write(port, val, UARTDM_DMEN);
 446
 447	if (msm_port->is_uartdm > UARTDM_1P3) {
 448		msm_write(port, UART_CR_CMD_RESET_TX, UART_CR);
 449		msm_write(port, UART_CR_TX_ENABLE, UART_CR);
 450	}
 451
 452	count = dma->count - state.residue;
 453	port->icount.tx += count;
 454	dma->count = 0;
 455
 456	xmit->tail += count;
 457	xmit->tail &= UART_XMIT_SIZE - 1;
 458
 459	/* Restore "Tx FIFO below watermark" interrupt */
 460	msm_port->imr |= UART_IMR_TXLEV;
 461	msm_write(port, msm_port->imr, UART_IMR);
 462
 463	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 464		uart_write_wakeup(port);
 465
 466	msm_handle_tx(port);
 467done:
 468	spin_unlock_irqrestore(&port->lock, flags);
 469}
 470
 471static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count)
 472{
 473	struct circ_buf *xmit = &msm_port->uart.state->xmit;
 474	struct uart_port *port = &msm_port->uart;
 475	struct msm_dma *dma = &msm_port->tx_dma;
 476	void *cpu_addr;
 477	int ret;
 478	u32 val;
 479
 480	cpu_addr = &xmit->buf[xmit->tail];
 481
 482	dma->phys = dma_map_single(port->dev, cpu_addr, count, dma->dir);
 483	ret = dma_mapping_error(port->dev, dma->phys);
 484	if (ret)
 485		return ret;
 486
 487	dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
 488						count, DMA_MEM_TO_DEV,
 489						DMA_PREP_INTERRUPT |
 490						DMA_PREP_FENCE);
 491	if (!dma->desc) {
 492		ret = -EIO;
 493		goto unmap;
 494	}
 495
 496	dma->desc->callback = msm_complete_tx_dma;
 497	dma->desc->callback_param = msm_port;
 498
 499	dma->cookie = dmaengine_submit(dma->desc);
 500	ret = dma_submit_error(dma->cookie);
 501	if (ret)
 502		goto unmap;
 503
 504	/*
 505	 * Using DMA complete for Tx FIFO reload, no need for
 506	 * "Tx FIFO below watermark" one, disable it
 507	 */
 508	msm_port->imr &= ~UART_IMR_TXLEV;
 509	msm_write(port, msm_port->imr, UART_IMR);
 510
 511	dma->count = count;
 512
 513	val = msm_read(port, UARTDM_DMEN);
 514	val |= dma->enable_bit;
 515
 516	if (msm_port->is_uartdm < UARTDM_1P4)
 517		msm_write(port, val, UARTDM_DMEN);
 518
 519	msm_reset_dm_count(port, count);
 520
 521	if (msm_port->is_uartdm > UARTDM_1P3)
 522		msm_write(port, val, UARTDM_DMEN);
 523
 524	dma_async_issue_pending(dma->chan);
 525	return 0;
 526unmap:
 527	dma_unmap_single(port->dev, dma->phys, count, dma->dir);
 528	return ret;
 529}
 530
 531static void msm_complete_rx_dma(void *args)
 532{
 533	struct msm_port *msm_port = args;
 534	struct uart_port *port = &msm_port->uart;
 535	struct tty_port *tport = &port->state->port;
 536	struct msm_dma *dma = &msm_port->rx_dma;
 537	int count = 0, i, sysrq;
 538	unsigned long flags;
 539	u32 val;
 540
 541	spin_lock_irqsave(&port->lock, flags);
 542
 543	/* Already stopped */
 544	if (!dma->count)
 545		goto done;
 546
 547	val = msm_read(port, UARTDM_DMEN);
 548	val &= ~dma->enable_bit;
 549	msm_write(port, val, UARTDM_DMEN);
 550
 551	if (msm_read(port, UART_SR) & UART_SR_OVERRUN) {
 552		port->icount.overrun++;
 553		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 554		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
 555	}
 556
 557	count = msm_read(port, UARTDM_RX_TOTAL_SNAP);
 558
 559	port->icount.rx += count;
 560
 561	dma->count = 0;
 562
 563	dma_unmap_single(port->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
 564
 565	for (i = 0; i < count; i++) {
 566		char flag = TTY_NORMAL;
 567
 568		if (msm_port->break_detected && dma->virt[i] == 0) {
 569			port->icount.brk++;
 570			flag = TTY_BREAK;
 571			msm_port->break_detected = false;
 572			if (uart_handle_break(port))
 573				continue;
 574		}
 575
 576		if (!(port->read_status_mask & UART_SR_RX_BREAK))
 577			flag = TTY_NORMAL;
 578
 579		spin_unlock_irqrestore(&port->lock, flags);
 580		sysrq = uart_handle_sysrq_char(port, dma->virt[i]);
 581		spin_lock_irqsave(&port->lock, flags);
 582		if (!sysrq)
 583			tty_insert_flip_char(tport, dma->virt[i], flag);
 584	}
 585
 586	msm_start_rx_dma(msm_port);
 587done:
 588	spin_unlock_irqrestore(&port->lock, flags);
 589
 590	if (count)
 591		tty_flip_buffer_push(tport);
 592}
 593
 594static void msm_start_rx_dma(struct msm_port *msm_port)
 595{
 596	struct msm_dma *dma = &msm_port->rx_dma;
 597	struct uart_port *uart = &msm_port->uart;
 598	u32 val;
 599	int ret;
 600
 601	if (!dma->chan)
 602		return;
 603
 604	dma->phys = dma_map_single(uart->dev, dma->virt,
 605				   UARTDM_RX_SIZE, dma->dir);
 606	ret = dma_mapping_error(uart->dev, dma->phys);
 607	if (ret)
 608		goto sw_mode;
 609
 610	dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
 611						UARTDM_RX_SIZE, DMA_DEV_TO_MEM,
 612						DMA_PREP_INTERRUPT);
 613	if (!dma->desc)
 614		goto unmap;
 615
 616	dma->desc->callback = msm_complete_rx_dma;
 617	dma->desc->callback_param = msm_port;
 618
 619	dma->cookie = dmaengine_submit(dma->desc);
 620	ret = dma_submit_error(dma->cookie);
 621	if (ret)
 622		goto unmap;
 623	/*
 624	 * Using DMA for FIFO off-load, no need for "Rx FIFO over
 625	 * watermark" or "stale" interrupts, disable them
 626	 */
 627	msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
 628
 629	/*
 630	 * Well, when DMA is ADM3 engine(implied by <= UARTDM v1.3),
 631	 * we need RXSTALE to flush input DMA fifo to memory
 632	 */
 633	if (msm_port->is_uartdm < UARTDM_1P4)
 634		msm_port->imr |= UART_IMR_RXSTALE;
 635
 636	msm_write(uart, msm_port->imr, UART_IMR);
 637
 638	dma->count = UARTDM_RX_SIZE;
 639
 640	dma_async_issue_pending(dma->chan);
 641
 642	msm_write(uart, UART_CR_CMD_RESET_STALE_INT, UART_CR);
 643	msm_write(uart, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
 644
 645	val = msm_read(uart, UARTDM_DMEN);
 646	val |= dma->enable_bit;
 647
 648	if (msm_port->is_uartdm < UARTDM_1P4)
 649		msm_write(uart, val, UARTDM_DMEN);
 650
 651	msm_write(uart, UARTDM_RX_SIZE, UARTDM_DMRX);
 652
 653	if (msm_port->is_uartdm > UARTDM_1P3)
 654		msm_write(uart, val, UARTDM_DMEN);
 655
 656	return;
 657unmap:
 658	dma_unmap_single(uart->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
 659
 660sw_mode:
 661	/*
 662	 * Switch from DMA to SW/FIFO mode. After clearing Rx BAM (UARTDM_DMEN),
 663	 * receiver must be reset.
 664	 */
 665	msm_write(uart, UART_CR_CMD_RESET_RX, UART_CR);
 666	msm_write(uart, UART_CR_RX_ENABLE, UART_CR);
 667
 668	msm_write(uart, UART_CR_CMD_RESET_STALE_INT, UART_CR);
 669	msm_write(uart, 0xFFFFFF, UARTDM_DMRX);
 670	msm_write(uart, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
 671
 672	/* Re-enable RX interrupts */
 673	msm_port->imr |= (UART_IMR_RXLEV | UART_IMR_RXSTALE);
 674	msm_write(uart, msm_port->imr, UART_IMR);
 675}
 676
 677static void msm_stop_rx(struct uart_port *port)
 678{
 679	struct msm_port *msm_port = UART_TO_MSM(port);
 680	struct msm_dma *dma = &msm_port->rx_dma;
 681
 682	msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
 683	msm_write(port, msm_port->imr, UART_IMR);
 684
 685	if (dma->chan)
 686		msm_stop_dma(port, dma);
 687}
 688
 689static void msm_enable_ms(struct uart_port *port)
 690{
 691	struct msm_port *msm_port = UART_TO_MSM(port);
 692
 693	msm_port->imr |= UART_IMR_DELTA_CTS;
 694	msm_write(port, msm_port->imr, UART_IMR);
 695}
 696
 697static void msm_handle_rx_dm(struct uart_port *port, unsigned int misr)
 698	__must_hold(&port->lock)
 699{
 700	struct tty_port *tport = &port->state->port;
 701	unsigned int sr;
 702	int count = 0;
 703	struct msm_port *msm_port = UART_TO_MSM(port);
 704
 705	if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
 706		port->icount.overrun++;
 707		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 708		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
 709	}
 710
 711	if (misr & UART_IMR_RXSTALE) {
 712		count = msm_read(port, UARTDM_RX_TOTAL_SNAP) -
 713			msm_port->old_snap_state;
 714		msm_port->old_snap_state = 0;
 715	} else {
 716		count = 4 * (msm_read(port, UART_RFWR));
 717		msm_port->old_snap_state += count;
 718	}
 719
 720	/* TODO: Precise error reporting */
 721
 722	port->icount.rx += count;
 723
 724	while (count > 0) {
 725		unsigned char buf[4];
 726		int sysrq, r_count, i;
 727
 728		sr = msm_read(port, UART_SR);
 729		if ((sr & UART_SR_RX_READY) == 0) {
 730			msm_port->old_snap_state -= count;
 731			break;
 732		}
 
 
 
 
 
 
 
 733
 734		ioread32_rep(port->membase + UARTDM_RF, buf, 1);
 735		r_count = min_t(int, count, sizeof(buf));
 736
 737		for (i = 0; i < r_count; i++) {
 738			char flag = TTY_NORMAL;
 739
 740			if (msm_port->break_detected && buf[i] == 0) {
 741				port->icount.brk++;
 742				flag = TTY_BREAK;
 743				msm_port->break_detected = false;
 744				if (uart_handle_break(port))
 745					continue;
 746			}
 747
 748			if (!(port->read_status_mask & UART_SR_RX_BREAK))
 749				flag = TTY_NORMAL;
 750
 751			spin_unlock(&port->lock);
 752			sysrq = uart_handle_sysrq_char(port, buf[i]);
 753			spin_lock(&port->lock);
 754			if (!sysrq)
 755				tty_insert_flip_char(tport, buf[i], flag);
 756		}
 757		count -= r_count;
 758	}
 759
 760	tty_flip_buffer_push(tport);
 761
 762	if (misr & (UART_IMR_RXSTALE))
 763		msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
 764	msm_write(port, 0xFFFFFF, UARTDM_DMRX);
 765	msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
 766
 767	/* Try to use DMA */
 768	msm_start_rx_dma(msm_port);
 769}
 770
 771static void msm_handle_rx(struct uart_port *port)
 772	__must_hold(&port->lock)
 773{
 774	struct tty_port *tport = &port->state->port;
 775	unsigned int sr;
 776
 777	/*
 778	 * Handle overrun. My understanding of the hardware is that overrun
 779	 * is not tied to the RX buffer, so we handle the case out of band.
 780	 */
 781	if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
 782		port->icount.overrun++;
 783		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 784		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
 785	}
 786
 787	/* and now the main RX loop */
 788	while ((sr = msm_read(port, UART_SR)) & UART_SR_RX_READY) {
 789		unsigned int c;
 790		char flag = TTY_NORMAL;
 791		int sysrq;
 792
 793		c = msm_read(port, UART_RF);
 794
 795		if (sr & UART_SR_RX_BREAK) {
 796			port->icount.brk++;
 797			if (uart_handle_break(port))
 798				continue;
 799		} else if (sr & UART_SR_PAR_FRAME_ERR) {
 800			port->icount.frame++;
 801		} else {
 802			port->icount.rx++;
 803		}
 804
 805		/* Mask conditions we're ignorning. */
 806		sr &= port->read_status_mask;
 807
 808		if (sr & UART_SR_RX_BREAK)
 809			flag = TTY_BREAK;
 810		else if (sr & UART_SR_PAR_FRAME_ERR)
 811			flag = TTY_FRAME;
 
 812
 813		spin_unlock(&port->lock);
 814		sysrq = uart_handle_sysrq_char(port, c);
 815		spin_lock(&port->lock);
 816		if (!sysrq)
 817			tty_insert_flip_char(tport, c, flag);
 818	}
 819
 820	tty_flip_buffer_push(tport);
 821}
 822
 823static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count)
 824{
 825	struct circ_buf *xmit = &port->state->xmit;
 826	struct msm_port *msm_port = UART_TO_MSM(port);
 827	unsigned int num_chars;
 828	unsigned int tf_pointer = 0;
 829	void __iomem *tf;
 830
 831	if (msm_port->is_uartdm)
 832		tf = port->membase + UARTDM_TF;
 833	else
 834		tf = port->membase + UART_TF;
 835
 836	if (tx_count && msm_port->is_uartdm)
 837		msm_reset_dm_count(port, tx_count);
 838
 839	while (tf_pointer < tx_count) {
 840		int i;
 841		char buf[4] = { 0 };
 842
 843		if (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
 844			break;
 845
 846		if (msm_port->is_uartdm)
 847			num_chars = min(tx_count - tf_pointer,
 848					(unsigned int)sizeof(buf));
 849		else
 850			num_chars = 1;
 851
 852		for (i = 0; i < num_chars; i++) {
 853			buf[i] = xmit->buf[xmit->tail + i];
 854			port->icount.tx++;
 855		}
 856
 857		iowrite32_rep(tf, buf, 1);
 858		xmit->tail = (xmit->tail + num_chars) & (UART_XMIT_SIZE - 1);
 859		tf_pointer += num_chars;
 860	}
 861
 862	/* disable tx interrupts if nothing more to send */
 863	if (uart_circ_empty(xmit))
 864		msm_stop_tx(port);
 865
 866	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 867		uart_write_wakeup(port);
 868}
 869
 870static void msm_handle_tx(struct uart_port *port)
 871{
 
 872	struct msm_port *msm_port = UART_TO_MSM(port);
 873	struct circ_buf *xmit = &msm_port->uart.state->xmit;
 874	struct msm_dma *dma = &msm_port->tx_dma;
 875	unsigned int pio_count, dma_count, dma_min;
 876	char buf[4] = { 0 };
 877	void __iomem *tf;
 878	int err = 0;
 879
 880	if (port->x_char) {
 881		if (msm_port->is_uartdm)
 882			tf = port->membase + UARTDM_TF;
 883		else
 884			tf = port->membase + UART_TF;
 885
 886		buf[0] = port->x_char;
 887
 888		if (msm_port->is_uartdm)
 889			msm_reset_dm_count(port, 1);
 890
 891		iowrite32_rep(tf, buf, 1);
 892		port->icount.tx++;
 893		port->x_char = 0;
 894		return;
 895	}
 896
 897	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
 898		msm_stop_tx(port);
 899		return;
 900	}
 901
 902	pio_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 903	dma_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
 904
 905	dma_min = 1;	/* Always DMA */
 906	if (msm_port->is_uartdm > UARTDM_1P3) {
 907		dma_count = UARTDM_TX_AIGN(dma_count);
 908		dma_min = UARTDM_BURST_SIZE;
 909	} else {
 910		if (dma_count > UARTDM_TX_MAX)
 911			dma_count = UARTDM_TX_MAX;
 912	}
 
 913
 914	if (pio_count > port->fifosize)
 915		pio_count = port->fifosize;
 916
 917	if (!dma->chan || dma_count < dma_min)
 918		msm_handle_tx_pio(port, pio_count);
 919	else
 920		err = msm_handle_tx_dma(msm_port, dma_count);
 921
 922	if (err)	/* fall back to PIO mode */
 923		msm_handle_tx_pio(port, pio_count);
 924}
 925
 926static void msm_handle_delta_cts(struct uart_port *port)
 927{
 928	msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
 929	port->icount.cts++;
 930	wake_up_interruptible(&port->state->port.delta_msr_wait);
 931}
 932
 933static irqreturn_t msm_uart_irq(int irq, void *dev_id)
 934{
 935	struct uart_port *port = dev_id;
 936	struct msm_port *msm_port = UART_TO_MSM(port);
 937	struct msm_dma *dma = &msm_port->rx_dma;
 938	unsigned long flags;
 939	unsigned int misr;
 940	u32 val;
 941
 942	spin_lock_irqsave(&port->lock, flags);
 943	misr = msm_read(port, UART_MISR);
 944	msm_write(port, 0, UART_IMR); /* disable interrupt */
 945
 946	if (misr & UART_IMR_RXBREAK_START) {
 947		msm_port->break_detected = true;
 948		msm_write(port, UART_CR_CMD_RESET_RXBREAK_START, UART_CR);
 949	}
 950
 951	if (misr & (UART_IMR_RXLEV | UART_IMR_RXSTALE)) {
 952		if (dma->count) {
 953			val = UART_CR_CMD_STALE_EVENT_DISABLE;
 954			msm_write(port, val, UART_CR);
 955			val = UART_CR_CMD_RESET_STALE_INT;
 956			msm_write(port, val, UART_CR);
 957			/*
 958			 * Flush DMA input fifo to memory, this will also
 959			 * trigger DMA RX completion
 960			 */
 961			dmaengine_terminate_all(dma->chan);
 962		} else if (msm_port->is_uartdm) {
 963			msm_handle_rx_dm(port, misr);
 964		} else {
 965			msm_handle_rx(port);
 966		}
 967	}
 968	if (misr & UART_IMR_TXLEV)
 969		msm_handle_tx(port);
 970	if (misr & UART_IMR_DELTA_CTS)
 971		msm_handle_delta_cts(port);
 972
 973	msm_write(port, msm_port->imr, UART_IMR); /* restore interrupt */
 974	spin_unlock_irqrestore(&port->lock, flags);
 975
 976	return IRQ_HANDLED;
 977}
 978
 979static unsigned int msm_tx_empty(struct uart_port *port)
 980{
 981	return (msm_read(port, UART_SR) & UART_SR_TX_EMPTY) ? TIOCSER_TEMT : 0;
 982}
 983
 984static unsigned int msm_get_mctrl(struct uart_port *port)
 985{
 986	return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS;
 987}
 988
 
 989static void msm_reset(struct uart_port *port)
 990{
 991	struct msm_port *msm_port = UART_TO_MSM(port);
 992	unsigned int mr;
 993
 994	/* reset everything */
 995	msm_write(port, UART_CR_CMD_RESET_RX, UART_CR);
 996	msm_write(port, UART_CR_CMD_RESET_TX, UART_CR);
 997	msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
 998	msm_write(port, UART_CR_CMD_RESET_BREAK_INT, UART_CR);
 999	msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
1000	msm_write(port, UART_CR_CMD_RESET_RFR, UART_CR);
1001	mr = msm_read(port, UART_MR1);
1002	mr &= ~UART_MR1_RX_RDY_CTL;
1003	msm_write(port, mr, UART_MR1);
1004
1005	/* Disable DM modes */
1006	if (msm_port->is_uartdm)
1007		msm_write(port, 0, UARTDM_DMEN);
1008}
1009
1010static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
1011{
1012	unsigned int mr;
1013
1014	mr = msm_read(port, UART_MR1);
1015
1016	if (!(mctrl & TIOCM_RTS)) {
1017		mr &= ~UART_MR1_RX_RDY_CTL;
1018		msm_write(port, mr, UART_MR1);
1019		msm_write(port, UART_CR_CMD_RESET_RFR, UART_CR);
1020	} else {
1021		mr |= UART_MR1_RX_RDY_CTL;
1022		msm_write(port, mr, UART_MR1);
1023	}
1024}
1025
1026static void msm_break_ctl(struct uart_port *port, int break_ctl)
1027{
1028	if (break_ctl)
1029		msm_write(port, UART_CR_CMD_START_BREAK, UART_CR);
1030	else
1031		msm_write(port, UART_CR_CMD_STOP_BREAK, UART_CR);
1032}
1033
1034struct msm_baud_map {
1035	u16	divisor;
1036	u8	code;
1037	u8	rxstale;
1038};
1039
1040static const struct msm_baud_map *
1041msm_find_best_baud(struct uart_port *port, unsigned int baud,
1042		   unsigned long *rate)
1043{
1044	struct msm_port *msm_port = UART_TO_MSM(port);
1045	unsigned int divisor, result;
1046	unsigned long target, old, best_rate = 0, diff, best_diff = ULONG_MAX;
1047	const struct msm_baud_map *entry, *end, *best;
1048	static const struct msm_baud_map table[] = {
1049		{    1, 0xff, 31 },
1050		{    2, 0xee, 16 },
1051		{    3, 0xdd,  8 },
1052		{    4, 0xcc,  6 },
1053		{    6, 0xbb,  6 },
1054		{    8, 0xaa,  6 },
1055		{   12, 0x99,  6 },
1056		{   16, 0x88,  1 },
1057		{   24, 0x77,  1 },
1058		{   32, 0x66,  1 },
1059		{   48, 0x55,  1 },
1060		{   96, 0x44,  1 },
1061		{  192, 0x33,  1 },
1062		{  384, 0x22,  1 },
1063		{  768, 0x11,  1 },
1064		{ 1536, 0x00,  1 },
1065	};
1066
1067	best = table; /* Default to smallest divider */
1068	target = clk_round_rate(msm_port->clk, 16 * baud);
1069	divisor = DIV_ROUND_CLOSEST(target, 16 * baud);
1070
1071	end = table + ARRAY_SIZE(table);
1072	entry = table;
1073	while (entry < end) {
1074		if (entry->divisor <= divisor) {
1075			result = target / entry->divisor / 16;
1076			diff = abs(result - baud);
1077
1078			/* Keep track of best entry */
1079			if (diff < best_diff) {
1080				best_diff = diff;
1081				best = entry;
1082				best_rate = target;
1083			}
1084
1085			if (result == baud)
1086				break;
1087		} else if (entry->divisor > divisor) {
1088			old = target;
1089			target = clk_round_rate(msm_port->clk, old + 1);
1090			/*
1091			 * The rate didn't get any faster so we can't do
1092			 * better at dividing it down
1093			 */
1094			if (target == old)
1095				break;
1096
1097			/* Start the divisor search over at this new rate */
1098			entry = table;
1099			divisor = DIV_ROUND_CLOSEST(target, 16 * baud);
1100			continue;
1101		}
1102		entry++;
1103	}
1104
1105	*rate = best_rate;
1106	return best;
1107}
1108
1109static int msm_set_baud_rate(struct uart_port *port, unsigned int baud,
1110			     unsigned long *saved_flags)
1111{
1112	unsigned int rxstale, watermark, mask;
1113	struct msm_port *msm_port = UART_TO_MSM(port);
1114	const struct msm_baud_map *entry;
1115	unsigned long flags, rate;
1116
1117	flags = *saved_flags;
1118	spin_unlock_irqrestore(&port->lock, flags);
1119
1120	entry = msm_find_best_baud(port, baud, &rate);
1121	clk_set_rate(msm_port->clk, rate);
1122	baud = rate / 16 / entry->divisor;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1123
1124	spin_lock_irqsave(&port->lock, flags);
1125	*saved_flags = flags;
1126	port->uartclk = rate;
1127
1128	msm_write(port, entry->code, UART_CSR);
1129
1130	/* RX stale watermark */
1131	rxstale = entry->rxstale;
1132	watermark = UART_IPR_STALE_LSB & rxstale;
1133	if (msm_port->is_uartdm) {
1134		mask = UART_DM_IPR_STALE_TIMEOUT_MSB;
1135	} else {
1136		watermark |= UART_IPR_RXSTALE_LAST;
1137		mask = UART_IPR_STALE_TIMEOUT_MSB;
1138	}
1139
1140	watermark |= mask & (rxstale << 2);
1141
1142	msm_write(port, watermark, UART_IPR);
1143
1144	/* set RX watermark */
1145	watermark = (port->fifosize * 3) / 4;
1146	msm_write(port, watermark, UART_RFWR);
1147
1148	/* set TX watermark */
1149	msm_write(port, 10, UART_TFWR);
1150
1151	msm_write(port, UART_CR_CMD_PROTECTION_EN, UART_CR);
1152	msm_reset(port);
1153
1154	/* Enable RX and TX */
1155	msm_write(port, UART_CR_TX_ENABLE | UART_CR_RX_ENABLE, UART_CR);
1156
1157	/* turn on RX and CTS interrupts */
1158	msm_port->imr = UART_IMR_RXLEV | UART_IMR_RXSTALE |
1159			UART_IMR_CURRENT_CTS | UART_IMR_RXBREAK_START;
1160
1161	msm_write(port, msm_port->imr, UART_IMR);
1162
1163	if (msm_port->is_uartdm) {
1164		msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
1165		msm_write(port, 0xFFFFFF, UARTDM_DMRX);
1166		msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
1167	}
1168
1169	return baud;
1170}
1171
 
1172static void msm_init_clock(struct uart_port *port)
1173{
1174	struct msm_port *msm_port = UART_TO_MSM(port);
1175
1176	clk_prepare_enable(msm_port->clk);
1177	clk_prepare_enable(msm_port->pclk);
 
1178	msm_serial_set_mnd_regs(port);
1179}
1180
1181static int msm_startup(struct uart_port *port)
1182{
1183	struct msm_port *msm_port = UART_TO_MSM(port);
1184	unsigned int data, rfr_level, mask;
1185	int ret;
1186
1187	snprintf(msm_port->name, sizeof(msm_port->name),
1188		 "msm_serial%d", port->line);
1189
 
 
 
 
 
1190	msm_init_clock(port);
1191
1192	if (likely(port->fifosize > 12))
1193		rfr_level = port->fifosize - 12;
1194	else
1195		rfr_level = port->fifosize;
1196
1197	/* set automatic RFR level */
1198	data = msm_read(port, UART_MR1);
1199
1200	if (msm_port->is_uartdm)
1201		mask = UART_DM_MR1_AUTO_RFR_LEVEL1;
1202	else
1203		mask = UART_MR1_AUTO_RFR_LEVEL1;
1204
1205	data &= ~mask;
1206	data &= ~UART_MR1_AUTO_RFR_LEVEL0;
1207	data |= mask & (rfr_level << 2);
1208	data |= UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
1209	msm_write(port, data, UART_MR1);
1210
1211	if (msm_port->is_uartdm) {
1212		msm_request_tx_dma(msm_port, msm_port->uart.mapbase);
1213		msm_request_rx_dma(msm_port, msm_port->uart.mapbase);
 
 
 
1214	}
1215
1216	ret = request_irq(port->irq, msm_uart_irq, IRQF_TRIGGER_HIGH,
1217			  msm_port->name, port);
1218	if (unlikely(ret))
1219		goto err_irq;
 
 
1220
1221	return 0;
 
1222
1223err_irq:
1224	if (msm_port->is_uartdm)
1225		msm_release_dma(msm_port);
1226
1227	clk_disable_unprepare(msm_port->pclk);
1228	clk_disable_unprepare(msm_port->clk);
 
1229
1230	return ret;
 
 
 
 
 
 
 
1231}
1232
1233static void msm_shutdown(struct uart_port *port)
1234{
1235	struct msm_port *msm_port = UART_TO_MSM(port);
1236
1237	msm_port->imr = 0;
1238	msm_write(port, 0, UART_IMR); /* disable interrupts */
1239
1240	if (msm_port->is_uartdm)
1241		msm_release_dma(msm_port);
1242
1243	clk_disable_unprepare(msm_port->clk);
1244
1245	free_irq(port->irq, port);
1246}
1247
1248static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
1249			    struct ktermios *old)
1250{
1251	struct msm_port *msm_port = UART_TO_MSM(port);
1252	struct msm_dma *dma = &msm_port->rx_dma;
1253	unsigned long flags;
1254	unsigned int baud, mr;
1255
1256	spin_lock_irqsave(&port->lock, flags);
1257
1258	if (dma->chan) /* Terminate if any */
1259		msm_stop_dma(port, dma);
1260
1261	/* calculate and set baud rate */
1262	baud = uart_get_baud_rate(port, termios, old, 300, 4000000);
1263	baud = msm_set_baud_rate(port, baud, &flags);
1264	if (tty_termios_baud_rate(termios))
1265		tty_termios_encode_baud_rate(termios, baud, baud);
1266
1267	/* calculate parity */
1268	mr = msm_read(port, UART_MR2);
1269	mr &= ~UART_MR2_PARITY_MODE;
1270	if (termios->c_cflag & PARENB) {
1271		if (termios->c_cflag & PARODD)
1272			mr |= UART_MR2_PARITY_MODE_ODD;
1273		else if (termios->c_cflag & CMSPAR)
1274			mr |= UART_MR2_PARITY_MODE_SPACE;
1275		else
1276			mr |= UART_MR2_PARITY_MODE_EVEN;
1277	}
1278
1279	/* calculate bits per char */
1280	mr &= ~UART_MR2_BITS_PER_CHAR;
1281	switch (termios->c_cflag & CSIZE) {
1282	case CS5:
1283		mr |= UART_MR2_BITS_PER_CHAR_5;
1284		break;
1285	case CS6:
1286		mr |= UART_MR2_BITS_PER_CHAR_6;
1287		break;
1288	case CS7:
1289		mr |= UART_MR2_BITS_PER_CHAR_7;
1290		break;
1291	case CS8:
1292	default:
1293		mr |= UART_MR2_BITS_PER_CHAR_8;
1294		break;
1295	}
1296
1297	/* calculate stop bits */
1298	mr &= ~(UART_MR2_STOP_BIT_LEN_ONE | UART_MR2_STOP_BIT_LEN_TWO);
1299	if (termios->c_cflag & CSTOPB)
1300		mr |= UART_MR2_STOP_BIT_LEN_TWO;
1301	else
1302		mr |= UART_MR2_STOP_BIT_LEN_ONE;
1303
1304	/* set parity, bits per char, and stop bit */
1305	msm_write(port, mr, UART_MR2);
1306
1307	/* calculate and set hardware flow control */
1308	mr = msm_read(port, UART_MR1);
1309	mr &= ~(UART_MR1_CTS_CTL | UART_MR1_RX_RDY_CTL);
1310	if (termios->c_cflag & CRTSCTS) {
1311		mr |= UART_MR1_CTS_CTL;
1312		mr |= UART_MR1_RX_RDY_CTL;
1313	}
1314	msm_write(port, mr, UART_MR1);
1315
1316	/* Configure status bits to ignore based on termio flags. */
1317	port->read_status_mask = 0;
1318	if (termios->c_iflag & INPCK)
1319		port->read_status_mask |= UART_SR_PAR_FRAME_ERR;
1320	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1321		port->read_status_mask |= UART_SR_RX_BREAK;
1322
1323	uart_update_timeout(port, termios->c_cflag, baud);
1324
1325	/* Try to use DMA */
1326	msm_start_rx_dma(msm_port);
1327
1328	spin_unlock_irqrestore(&port->lock, flags);
1329}
1330
1331static const char *msm_type(struct uart_port *port)
1332{
1333	return "MSM";
1334}
1335
1336static void msm_release_port(struct uart_port *port)
1337{
1338	struct platform_device *pdev = to_platform_device(port->dev);
 
1339	struct resource *uart_resource;
 
1340	resource_size_t size;
1341
1342	uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1343	if (unlikely(!uart_resource))
1344		return;
1345	size = resource_size(uart_resource);
1346
1347	release_mem_region(port->mapbase, size);
1348	iounmap(port->membase);
1349	port->membase = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1350}
1351
1352static int msm_request_port(struct uart_port *port)
1353{
 
1354	struct platform_device *pdev = to_platform_device(port->dev);
1355	struct resource *uart_resource;
 
1356	resource_size_t size;
1357	int ret;
1358
1359	uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1360	if (unlikely(!uart_resource))
1361		return -ENXIO;
1362
1363	size = resource_size(uart_resource);
1364
1365	if (!request_mem_region(port->mapbase, size, "msm_serial"))
1366		return -EBUSY;
1367
1368	port->membase = ioremap(port->mapbase, size);
1369	if (!port->membase) {
1370		ret = -EBUSY;
1371		goto fail_release_port;
1372	}
1373
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1374	return 0;
1375
 
 
1376fail_release_port:
1377	release_mem_region(port->mapbase, size);
1378	return ret;
1379}
1380
1381static void msm_config_port(struct uart_port *port, int flags)
1382{
 
1383	int ret;
1384
1385	if (flags & UART_CONFIG_TYPE) {
1386		port->type = PORT_MSM;
1387		ret = msm_request_port(port);
1388		if (ret)
1389			return;
1390	}
 
 
 
 
1391}
1392
1393static int msm_verify_port(struct uart_port *port, struct serial_struct *ser)
1394{
1395	if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_MSM))
1396		return -EINVAL;
1397	if (unlikely(port->irq != ser->irq))
1398		return -EINVAL;
1399	return 0;
1400}
1401
1402static void msm_power(struct uart_port *port, unsigned int state,
1403		      unsigned int oldstate)
1404{
1405	struct msm_port *msm_port = UART_TO_MSM(port);
1406
1407	switch (state) {
1408	case 0:
1409		clk_prepare_enable(msm_port->clk);
1410		clk_prepare_enable(msm_port->pclk);
 
1411		break;
1412	case 3:
1413		clk_disable_unprepare(msm_port->clk);
1414		clk_disable_unprepare(msm_port->pclk);
 
1415		break;
1416	default:
1417		pr_err("msm_serial: Unknown PM state %d\n", state);
1418	}
1419}
1420
1421#ifdef CONFIG_CONSOLE_POLL
1422static int msm_poll_get_char_single(struct uart_port *port)
1423{
1424	struct msm_port *msm_port = UART_TO_MSM(port);
1425	unsigned int rf_reg = msm_port->is_uartdm ? UARTDM_RF : UART_RF;
1426
1427	if (!(msm_read(port, UART_SR) & UART_SR_RX_READY))
1428		return NO_POLL_CHAR;
1429
1430	return msm_read(port, rf_reg) & 0xff;
1431}
1432
1433static int msm_poll_get_char_dm(struct uart_port *port)
1434{
1435	int c;
1436	static u32 slop;
1437	static int count;
1438	unsigned char *sp = (unsigned char *)&slop;
1439
1440	/* Check if a previous read had more than one char */
1441	if (count) {
1442		c = sp[sizeof(slop) - count];
1443		count--;
1444	/* Or if FIFO is empty */
1445	} else if (!(msm_read(port, UART_SR) & UART_SR_RX_READY)) {
1446		/*
1447		 * If RX packing buffer has less than a word, force stale to
1448		 * push contents into RX FIFO
1449		 */
1450		count = msm_read(port, UARTDM_RXFS);
1451		count = (count >> UARTDM_RXFS_BUF_SHIFT) & UARTDM_RXFS_BUF_MASK;
1452		if (count) {
1453			msm_write(port, UART_CR_CMD_FORCE_STALE, UART_CR);
1454			slop = msm_read(port, UARTDM_RF);
1455			c = sp[0];
1456			count--;
1457			msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
1458			msm_write(port, 0xFFFFFF, UARTDM_DMRX);
1459			msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE,
1460				  UART_CR);
1461		} else {
1462			c = NO_POLL_CHAR;
1463		}
1464	/* FIFO has a word */
1465	} else {
1466		slop = msm_read(port, UARTDM_RF);
1467		c = sp[0];
1468		count = sizeof(slop) - 1;
1469	}
1470
1471	return c;
1472}
1473
1474static int msm_poll_get_char(struct uart_port *port)
1475{
1476	u32 imr;
1477	int c;
1478	struct msm_port *msm_port = UART_TO_MSM(port);
1479
1480	/* Disable all interrupts */
1481	imr = msm_read(port, UART_IMR);
1482	msm_write(port, 0, UART_IMR);
1483
1484	if (msm_port->is_uartdm)
1485		c = msm_poll_get_char_dm(port);
1486	else
1487		c = msm_poll_get_char_single(port);
1488
1489	/* Enable interrupts */
1490	msm_write(port, imr, UART_IMR);
1491
1492	return c;
1493}
1494
1495static void msm_poll_put_char(struct uart_port *port, unsigned char c)
1496{
1497	u32 imr;
1498	struct msm_port *msm_port = UART_TO_MSM(port);
1499
1500	/* Disable all interrupts */
1501	imr = msm_read(port, UART_IMR);
1502	msm_write(port, 0, UART_IMR);
1503
1504	if (msm_port->is_uartdm)
1505		msm_reset_dm_count(port, 1);
1506
1507	/* Wait until FIFO is empty */
1508	while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
1509		cpu_relax();
1510
1511	/* Write a character */
1512	msm_write(port, c, msm_port->is_uartdm ? UARTDM_TF : UART_TF);
1513
1514	/* Wait until FIFO is empty */
1515	while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
1516		cpu_relax();
1517
1518	/* Enable interrupts */
1519	msm_write(port, imr, UART_IMR);
1520}
1521#endif
1522
1523static const struct uart_ops msm_uart_pops = {
1524	.tx_empty = msm_tx_empty,
1525	.set_mctrl = msm_set_mctrl,
1526	.get_mctrl = msm_get_mctrl,
1527	.stop_tx = msm_stop_tx,
1528	.start_tx = msm_start_tx,
1529	.stop_rx = msm_stop_rx,
1530	.enable_ms = msm_enable_ms,
1531	.break_ctl = msm_break_ctl,
1532	.startup = msm_startup,
1533	.shutdown = msm_shutdown,
1534	.set_termios = msm_set_termios,
1535	.type = msm_type,
1536	.release_port = msm_release_port,
1537	.request_port = msm_request_port,
1538	.config_port = msm_config_port,
1539	.verify_port = msm_verify_port,
1540	.pm = msm_power,
1541#ifdef CONFIG_CONSOLE_POLL
1542	.poll_get_char	= msm_poll_get_char,
1543	.poll_put_char	= msm_poll_put_char,
1544#endif
1545};
1546
1547static struct msm_port msm_uart_ports[] = {
1548	{
1549		.uart = {
1550			.iotype = UPIO_MEM,
1551			.ops = &msm_uart_pops,
1552			.flags = UPF_BOOT_AUTOCONF,
1553			.fifosize = 64,
1554			.line = 0,
1555		},
1556	},
1557	{
1558		.uart = {
1559			.iotype = UPIO_MEM,
1560			.ops = &msm_uart_pops,
1561			.flags = UPF_BOOT_AUTOCONF,
1562			.fifosize = 64,
1563			.line = 1,
1564		},
1565	},
1566	{
1567		.uart = {
1568			.iotype = UPIO_MEM,
1569			.ops = &msm_uart_pops,
1570			.flags = UPF_BOOT_AUTOCONF,
1571			.fifosize = 64,
1572			.line = 2,
1573		},
1574	},
1575};
1576
1577#define UART_NR	ARRAY_SIZE(msm_uart_ports)
1578
1579static inline struct uart_port *msm_get_port_from_line(unsigned int line)
1580{
1581	return &msm_uart_ports[line].uart;
1582}
1583
1584#ifdef CONFIG_SERIAL_MSM_CONSOLE
1585static void __msm_console_write(struct uart_port *port, const char *s,
1586				unsigned int count, bool is_uartdm)
1587{
1588	int i;
1589	int num_newlines = 0;
1590	bool replaced = false;
1591	void __iomem *tf;
1592	int locked = 1;
1593
1594	if (is_uartdm)
1595		tf = port->membase + UARTDM_TF;
1596	else
1597		tf = port->membase + UART_TF;
1598
1599	/* Account for newlines that will get a carriage return added */
1600	for (i = 0; i < count; i++)
1601		if (s[i] == '\n')
1602			num_newlines++;
1603	count += num_newlines;
1604
1605	if (port->sysrq)
1606		locked = 0;
1607	else if (oops_in_progress)
1608		locked = spin_trylock(&port->lock);
1609	else
1610		spin_lock(&port->lock);
1611
1612	if (is_uartdm)
1613		msm_reset_dm_count(port, count);
1614
1615	i = 0;
1616	while (i < count) {
1617		int j;
1618		unsigned int num_chars;
1619		char buf[4] = { 0 };
1620
1621		if (is_uartdm)
1622			num_chars = min(count - i, (unsigned int)sizeof(buf));
1623		else
1624			num_chars = 1;
1625
1626		for (j = 0; j < num_chars; j++) {
1627			char c = *s;
1628
1629			if (c == '\n' && !replaced) {
1630				buf[j] = '\r';
1631				j++;
1632				replaced = true;
1633			}
1634			if (j < num_chars) {
1635				buf[j] = c;
1636				s++;
1637				replaced = false;
1638			}
1639		}
1640
1641		while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
1642			cpu_relax();
 
1643
1644		iowrite32_rep(tf, buf, 1);
1645		i += num_chars;
1646	}
1647
1648	if (locked)
1649		spin_unlock(&port->lock);
 
1650}
1651
1652static void msm_console_write(struct console *co, const char *s,
1653			      unsigned int count)
1654{
1655	struct uart_port *port;
1656	struct msm_port *msm_port;
1657
1658	BUG_ON(co->index < 0 || co->index >= UART_NR);
1659
1660	port = msm_get_port_from_line(co->index);
1661	msm_port = UART_TO_MSM(port);
1662
1663	__msm_console_write(port, s, count, msm_port->is_uartdm);
 
 
1664}
1665
1666static int msm_console_setup(struct console *co, char *options)
1667{
1668	struct uart_port *port;
1669	int baud = 115200;
1670	int bits = 8;
1671	int parity = 'n';
1672	int flow = 'n';
1673
1674	if (unlikely(co->index >= UART_NR || co->index < 0))
1675		return -ENXIO;
1676
1677	port = msm_get_port_from_line(co->index);
 
1678
1679	if (unlikely(!port->membase))
1680		return -ENXIO;
1681
1682	msm_init_clock(port);
1683
1684	if (options)
1685		uart_parse_options(options, &baud, &parity, &bits, &flow);
1686
1687	pr_info("msm_serial: console setup on port #%d\n", port->line);
1688
1689	return uart_set_options(port, co, baud, parity, bits, flow);
1690}
1691
1692static void
1693msm_serial_early_write(struct console *con, const char *s, unsigned n)
1694{
1695	struct earlycon_device *dev = con->data;
1696
1697	__msm_console_write(&dev->port, s, n, false);
1698}
1699
1700static int __init
1701msm_serial_early_console_setup(struct earlycon_device *device, const char *opt)
1702{
1703	if (!device->port.membase)
1704		return -ENODEV;
1705
1706	device->con->write = msm_serial_early_write;
1707	return 0;
1708}
1709OF_EARLYCON_DECLARE(msm_serial, "qcom,msm-uart",
1710		    msm_serial_early_console_setup);
1711
1712static void
1713msm_serial_early_write_dm(struct console *con, const char *s, unsigned n)
1714{
1715	struct earlycon_device *dev = con->data;
1716
1717	__msm_console_write(&dev->port, s, n, true);
1718}
 
 
1719
1720static int __init
1721msm_serial_early_console_setup_dm(struct earlycon_device *device,
1722				  const char *opt)
1723{
1724	if (!device->port.membase)
1725		return -ENODEV;
1726
1727	device->con->write = msm_serial_early_write_dm;
1728	return 0;
1729}
1730OF_EARLYCON_DECLARE(msm_serial_dm, "qcom,msm-uartdm",
1731		    msm_serial_early_console_setup_dm);
1732
1733static struct uart_driver msm_uart_driver;
1734
1735static struct console msm_console = {
1736	.name = "ttyMSM",
1737	.write = msm_console_write,
1738	.device = uart_console_device,
1739	.setup = msm_console_setup,
1740	.flags = CON_PRINTBUFFER,
1741	.index = -1,
1742	.data = &msm_uart_driver,
1743};
1744
1745#define MSM_CONSOLE	(&msm_console)
1746
1747#else
1748#define MSM_CONSOLE	NULL
1749#endif
1750
1751static struct uart_driver msm_uart_driver = {
1752	.owner = THIS_MODULE,
1753	.driver_name = "msm_serial",
1754	.dev_name = "ttyMSM",
1755	.nr = UART_NR,
1756	.cons = MSM_CONSOLE,
1757};
1758
1759static atomic_t msm_uart_next_id = ATOMIC_INIT(0);
1760
1761static const struct of_device_id msm_uartdm_table[] = {
1762	{ .compatible = "qcom,msm-uartdm-v1.1", .data = (void *)UARTDM_1P1 },
1763	{ .compatible = "qcom,msm-uartdm-v1.2", .data = (void *)UARTDM_1P2 },
1764	{ .compatible = "qcom,msm-uartdm-v1.3", .data = (void *)UARTDM_1P3 },
1765	{ .compatible = "qcom,msm-uartdm-v1.4", .data = (void *)UARTDM_1P4 },
1766	{ }
1767};
1768
1769static int msm_serial_probe(struct platform_device *pdev)
1770{
1771	struct msm_port *msm_port;
1772	struct resource *resource;
1773	struct uart_port *port;
1774	const struct of_device_id *id;
1775	int irq, line;
1776
1777	if (pdev->dev.of_node)
1778		line = of_alias_get_id(pdev->dev.of_node, "serial");
1779	else
1780		line = pdev->id;
1781
1782	if (line < 0)
1783		line = atomic_inc_return(&msm_uart_next_id) - 1;
1784
1785	if (unlikely(line < 0 || line >= UART_NR))
1786		return -ENXIO;
1787
1788	dev_info(&pdev->dev, "msm_serial: detected port #%d\n", line);
1789
1790	port = msm_get_port_from_line(line);
1791	port->dev = &pdev->dev;
1792	msm_port = UART_TO_MSM(port);
1793
1794	id = of_match_device(msm_uartdm_table, &pdev->dev);
1795	if (id)
1796		msm_port->is_uartdm = (unsigned long)id->data;
1797	else
1798		msm_port->is_uartdm = 0;
1799
1800	msm_port->clk = devm_clk_get(&pdev->dev, "core");
1801	if (IS_ERR(msm_port->clk))
1802		return PTR_ERR(msm_port->clk);
1803
1804	if (msm_port->is_uartdm) {
1805		msm_port->pclk = devm_clk_get(&pdev->dev, "iface");
1806		if (IS_ERR(msm_port->pclk))
1807			return PTR_ERR(msm_port->pclk);
 
 
1808	}
1809
 
 
 
 
 
 
 
1810	port->uartclk = clk_get_rate(msm_port->clk);
1811	dev_info(&pdev->dev, "uartclk = %d\n", port->uartclk);
 
1812
1813	resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1814	if (unlikely(!resource))
1815		return -ENXIO;
1816	port->mapbase = resource->start;
1817
1818	irq = platform_get_irq(pdev, 0);
1819	if (unlikely(irq < 0))
1820		return -ENXIO;
1821	port->irq = irq;
1822	port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_MSM_CONSOLE);
1823
1824	platform_set_drvdata(pdev, port);
1825
1826	return uart_add_one_port(&msm_uart_driver, port);
1827}
1828
1829static int msm_serial_remove(struct platform_device *pdev)
1830{
1831	struct uart_port *port = platform_get_drvdata(pdev);
1832
1833	uart_remove_one_port(&msm_uart_driver, port);
1834
1835	return 0;
1836}
1837
1838static const struct of_device_id msm_match_table[] = {
1839	{ .compatible = "qcom,msm-uart" },
1840	{ .compatible = "qcom,msm-uartdm" },
1841	{}
1842};
1843MODULE_DEVICE_TABLE(of, msm_match_table);
1844
1845static int __maybe_unused msm_serial_suspend(struct device *dev)
1846{
1847	struct msm_port *port = dev_get_drvdata(dev);
1848
1849	uart_suspend_port(&msm_uart_driver, &port->uart);
1850
1851	return 0;
1852}
1853
1854static int __maybe_unused msm_serial_resume(struct device *dev)
1855{
1856	struct msm_port *port = dev_get_drvdata(dev);
1857
1858	uart_resume_port(&msm_uart_driver, &port->uart);
1859
1860	return 0;
1861}
1862
1863static const struct dev_pm_ops msm_serial_dev_pm_ops = {
1864	SET_SYSTEM_SLEEP_PM_OPS(msm_serial_suspend, msm_serial_resume)
1865};
1866
1867static struct platform_driver msm_platform_driver = {
1868	.remove = msm_serial_remove,
1869	.probe = msm_serial_probe,
1870	.driver = {
1871		.name = "msm_serial",
1872		.pm = &msm_serial_dev_pm_ops,
1873		.of_match_table = msm_match_table,
1874	},
1875};
1876
1877static int __init msm_serial_init(void)
1878{
1879	int ret;
1880
1881	ret = uart_register_driver(&msm_uart_driver);
1882	if (unlikely(ret))
1883		return ret;
1884
1885	ret = platform_driver_register(&msm_platform_driver);
1886	if (unlikely(ret))
1887		uart_unregister_driver(&msm_uart_driver);
1888
1889	pr_info("msm_serial: driver initialized\n");
1890
1891	return ret;
1892}
1893
1894static void __exit msm_serial_exit(void)
1895{
 
 
 
1896	platform_driver_unregister(&msm_platform_driver);
1897	uart_unregister_driver(&msm_uart_driver);
1898}
1899
1900module_init(msm_serial_init);
1901module_exit(msm_serial_exit);
1902
1903MODULE_AUTHOR("Robert Love <rlove@google.com>");
1904MODULE_DESCRIPTION("Driver for msm7x serial device");
1905MODULE_LICENSE("GPL");
v3.5.6
 
  1/*
  2 * Driver for msm7k serial device and console
  3 *
  4 * Copyright (C) 2007 Google, Inc.
  5 * Author: Robert Love <rlove@google.com>
  6 * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  7 *
  8 * This software is licensed under the terms of the GNU General Public
  9 * License version 2, as published by the Free Software Foundation, and
 10 * may be copied, distributed, and modified under those terms.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 */
 17
 18#if defined(CONFIG_SERIAL_MSM_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 19# define SUPPORT_SYSRQ
 20#endif
 21
 22#include <linux/atomic.h>
 23#include <linux/hrtimer.h>
 
 24#include <linux/module.h>
 25#include <linux/io.h>
 26#include <linux/ioport.h>
 27#include <linux/irq.h>
 28#include <linux/init.h>
 29#include <linux/console.h>
 30#include <linux/tty.h>
 31#include <linux/tty_flip.h>
 32#include <linux/serial_core.h>
 33#include <linux/serial.h>
 34#include <linux/clk.h>
 35#include <linux/platform_device.h>
 36#include <linux/delay.h>
 37#include <linux/of.h>
 38#include <linux/of_device.h>
 
 39
 40#include "msm_serial.h"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 41
 42struct msm_port {
 43	struct uart_port	uart;
 44	char			name[16];
 45	struct clk		*clk;
 46	struct clk		*pclk;
 47	unsigned int		imr;
 48	unsigned int            *gsbi_base;
 49	int			is_uartdm;
 50	unsigned int		old_snap_state;
 
 
 
 51};
 52
 53static inline void wait_for_xmitr(struct uart_port *port, int bits)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 54{
 55	if (!(msm_read(port, UART_SR) & UART_SR_TX_EMPTY))
 56		while ((msm_read(port, UART_ISR) & bits) != bits)
 57			cpu_relax();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 58}
 59
 60static void msm_stop_tx(struct uart_port *port)
 61{
 62	struct msm_port *msm_port = UART_TO_MSM(port);
 63
 64	msm_port->imr &= ~UART_IMR_TXLEV;
 65	msm_write(port, msm_port->imr, UART_IMR);
 66}
 67
 68static void msm_start_tx(struct uart_port *port)
 69{
 70	struct msm_port *msm_port = UART_TO_MSM(port);
 
 
 
 
 
 71
 72	msm_port->imr |= UART_IMR_TXLEV;
 73	msm_write(port, msm_port->imr, UART_IMR);
 74}
 75
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 76static void msm_stop_rx(struct uart_port *port)
 77{
 78	struct msm_port *msm_port = UART_TO_MSM(port);
 
 79
 80	msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
 81	msm_write(port, msm_port->imr, UART_IMR);
 
 
 
 82}
 83
 84static void msm_enable_ms(struct uart_port *port)
 85{
 86	struct msm_port *msm_port = UART_TO_MSM(port);
 87
 88	msm_port->imr |= UART_IMR_DELTA_CTS;
 89	msm_write(port, msm_port->imr, UART_IMR);
 90}
 91
 92static void handle_rx_dm(struct uart_port *port, unsigned int misr)
 
 93{
 94	struct tty_struct *tty = port->state->port.tty;
 95	unsigned int sr;
 96	int count = 0;
 97	struct msm_port *msm_port = UART_TO_MSM(port);
 98
 99	if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
100		port->icount.overrun++;
101		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
102		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
103	}
104
105	if (misr & UART_IMR_RXSTALE) {
106		count = msm_read(port, UARTDM_RX_TOTAL_SNAP) -
107			msm_port->old_snap_state;
108		msm_port->old_snap_state = 0;
109	} else {
110		count = 4 * (msm_read(port, UART_RFWR));
111		msm_port->old_snap_state += count;
112	}
113
114	/* TODO: Precise error reporting */
115
116	port->icount.rx += count;
117
118	while (count > 0) {
119		unsigned int c;
 
120
121		sr = msm_read(port, UART_SR);
122		if ((sr & UART_SR_RX_READY) == 0) {
123			msm_port->old_snap_state -= count;
124			break;
125		}
126		c = msm_read(port, UARTDM_RF);
127		if (sr & UART_SR_RX_BREAK) {
128			port->icount.brk++;
129			if (uart_handle_break(port))
130				continue;
131		} else if (sr & UART_SR_PAR_FRAME_ERR)
132			port->icount.frame++;
133
134		/* TODO: handle sysrq */
135		tty_insert_flip_string(tty, (char *) &c,
136				       (count > 4) ? 4 : count);
137		count -= 4;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
138	}
139
140	tty_flip_buffer_push(tty);
 
141	if (misr & (UART_IMR_RXSTALE))
142		msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
143	msm_write(port, 0xFFFFFF, UARTDM_DMRX);
144	msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
 
 
 
145}
146
147static void handle_rx(struct uart_port *port)
 
148{
149	struct tty_struct *tty = port->state->port.tty;
150	unsigned int sr;
151
152	/*
153	 * Handle overrun. My understanding of the hardware is that overrun
154	 * is not tied to the RX buffer, so we handle the case out of band.
155	 */
156	if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
157		port->icount.overrun++;
158		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
159		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
160	}
161
162	/* and now the main RX loop */
163	while ((sr = msm_read(port, UART_SR)) & UART_SR_RX_READY) {
164		unsigned int c;
165		char flag = TTY_NORMAL;
 
166
167		c = msm_read(port, UART_RF);
168
169		if (sr & UART_SR_RX_BREAK) {
170			port->icount.brk++;
171			if (uart_handle_break(port))
172				continue;
173		} else if (sr & UART_SR_PAR_FRAME_ERR) {
174			port->icount.frame++;
175		} else {
176			port->icount.rx++;
177		}
178
179		/* Mask conditions we're ignorning. */
180		sr &= port->read_status_mask;
181
182		if (sr & UART_SR_RX_BREAK) {
183			flag = TTY_BREAK;
184		} else if (sr & UART_SR_PAR_FRAME_ERR) {
185			flag = TTY_FRAME;
186		}
187
188		if (!uart_handle_sysrq_char(port, c))
189			tty_insert_flip_char(tty, c, flag);
 
 
 
190	}
191
192	tty_flip_buffer_push(tty);
193}
194
195static void reset_dm_count(struct uart_port *port)
196{
197	wait_for_xmitr(port, UART_ISR_TX_READY);
198	msm_write(port, 1, UARTDM_NCF_TX);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
199}
200
201static void handle_tx(struct uart_port *port)
202{
203	struct circ_buf *xmit = &port->state->xmit;
204	struct msm_port *msm_port = UART_TO_MSM(port);
205	int sent_tx;
 
 
 
 
 
206
207	if (port->x_char) {
208		if (msm_port->is_uartdm)
209			reset_dm_count(port);
 
 
 
 
210
211		msm_write(port, port->x_char,
212			  msm_port->is_uartdm ? UARTDM_TF : UART_TF);
 
 
213		port->icount.tx++;
214		port->x_char = 0;
 
215	}
216
217	if (msm_port->is_uartdm)
218		reset_dm_count(port);
 
 
 
 
 
219
220	while (msm_read(port, UART_SR) & UART_SR_TX_READY) {
221		if (uart_circ_empty(xmit)) {
222			/* disable tx interrupts */
223			msm_port->imr &= ~UART_IMR_TXLEV;
224			msm_write(port, msm_port->imr, UART_IMR);
225			break;
226		}
227		msm_write(port, xmit->buf[xmit->tail],
228			  msm_port->is_uartdm ? UARTDM_TF : UART_TF);
229
230		if (msm_port->is_uartdm)
231			reset_dm_count(port);
232
233		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
234		port->icount.tx++;
235		sent_tx = 1;
236	}
237
238	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
239		uart_write_wakeup(port);
240}
241
242static void handle_delta_cts(struct uart_port *port)
243{
244	msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
245	port->icount.cts++;
246	wake_up_interruptible(&port->state->port.delta_msr_wait);
247}
248
249static irqreturn_t msm_irq(int irq, void *dev_id)
250{
251	struct uart_port *port = dev_id;
252	struct msm_port *msm_port = UART_TO_MSM(port);
 
 
253	unsigned int misr;
 
254
255	spin_lock(&port->lock);
256	misr = msm_read(port, UART_MISR);
257	msm_write(port, 0, UART_IMR); /* disable interrupt */
258
 
 
 
 
 
259	if (misr & (UART_IMR_RXLEV | UART_IMR_RXSTALE)) {
260		if (msm_port->is_uartdm)
261			handle_rx_dm(port, misr);
262		else
263			handle_rx(port);
 
 
 
 
 
 
 
 
 
 
 
264	}
265	if (misr & UART_IMR_TXLEV)
266		handle_tx(port);
267	if (misr & UART_IMR_DELTA_CTS)
268		handle_delta_cts(port);
269
270	msm_write(port, msm_port->imr, UART_IMR); /* restore interrupt */
271	spin_unlock(&port->lock);
272
273	return IRQ_HANDLED;
274}
275
276static unsigned int msm_tx_empty(struct uart_port *port)
277{
278	return (msm_read(port, UART_SR) & UART_SR_TX_EMPTY) ? TIOCSER_TEMT : 0;
279}
280
281static unsigned int msm_get_mctrl(struct uart_port *port)
282{
283	return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS;
284}
285
286
287static void msm_reset(struct uart_port *port)
288{
 
 
 
289	/* reset everything */
290	msm_write(port, UART_CR_CMD_RESET_RX, UART_CR);
291	msm_write(port, UART_CR_CMD_RESET_TX, UART_CR);
292	msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
293	msm_write(port, UART_CR_CMD_RESET_BREAK_INT, UART_CR);
294	msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
295	msm_write(port, UART_CR_CMD_SET_RFR, UART_CR);
 
 
 
 
 
 
 
296}
297
298void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
299{
300	unsigned int mr;
 
301	mr = msm_read(port, UART_MR1);
302
303	if (!(mctrl & TIOCM_RTS)) {
304		mr &= ~UART_MR1_RX_RDY_CTL;
305		msm_write(port, mr, UART_MR1);
306		msm_write(port, UART_CR_CMD_RESET_RFR, UART_CR);
307	} else {
308		mr |= UART_MR1_RX_RDY_CTL;
309		msm_write(port, mr, UART_MR1);
310	}
311}
312
313static void msm_break_ctl(struct uart_port *port, int break_ctl)
314{
315	if (break_ctl)
316		msm_write(port, UART_CR_CMD_START_BREAK, UART_CR);
317	else
318		msm_write(port, UART_CR_CMD_STOP_BREAK, UART_CR);
319}
320
321static int msm_set_baud_rate(struct uart_port *port, unsigned int baud)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
322{
323	unsigned int baud_code, rxstale, watermark;
324	struct msm_port *msm_port = UART_TO_MSM(port);
 
 
 
 
 
325
326	switch (baud) {
327	case 300:
328		baud_code = UART_CSR_300;
329		rxstale = 1;
330		break;
331	case 600:
332		baud_code = UART_CSR_600;
333		rxstale = 1;
334		break;
335	case 1200:
336		baud_code = UART_CSR_1200;
337		rxstale = 1;
338		break;
339	case 2400:
340		baud_code = UART_CSR_2400;
341		rxstale = 1;
342		break;
343	case 4800:
344		baud_code = UART_CSR_4800;
345		rxstale = 1;
346		break;
347	case 9600:
348		baud_code = UART_CSR_9600;
349		rxstale = 2;
350		break;
351	case 14400:
352		baud_code = UART_CSR_14400;
353		rxstale = 3;
354		break;
355	case 19200:
356		baud_code = UART_CSR_19200;
357		rxstale = 4;
358		break;
359	case 28800:
360		baud_code = UART_CSR_28800;
361		rxstale = 6;
362		break;
363	case 38400:
364		baud_code = UART_CSR_38400;
365		rxstale = 8;
366		break;
367	case 57600:
368		baud_code = UART_CSR_57600;
369		rxstale = 16;
370		break;
371	case 115200:
372	default:
373		baud_code = UART_CSR_115200;
374		baud = 115200;
375		rxstale = 31;
376		break;
377	}
378
379	if (msm_port->is_uartdm)
380		msm_write(port, UART_CR_CMD_RESET_RX, UART_CR);
 
381
382	msm_write(port, baud_code, UART_CSR);
383
384	/* RX stale watermark */
 
385	watermark = UART_IPR_STALE_LSB & rxstale;
386	watermark |= UART_IPR_RXSTALE_LAST;
387	watermark |= UART_IPR_STALE_TIMEOUT_MSB & (rxstale << 2);
 
 
 
 
 
 
 
388	msm_write(port, watermark, UART_IPR);
389
390	/* set RX watermark */
391	watermark = (port->fifosize * 3) / 4;
392	msm_write(port, watermark, UART_RFWR);
393
394	/* set TX watermark */
395	msm_write(port, 10, UART_TFWR);
396
 
 
 
 
 
 
 
 
 
 
 
 
397	if (msm_port->is_uartdm) {
398		msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
399		msm_write(port, 0xFFFFFF, UARTDM_DMRX);
400		msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
401	}
402
403	return baud;
404}
405
406
407static void msm_init_clock(struct uart_port *port)
408{
409	struct msm_port *msm_port = UART_TO_MSM(port);
410
411	clk_enable(msm_port->clk);
412	if (!IS_ERR(msm_port->pclk))
413		clk_enable(msm_port->pclk);
414	msm_serial_set_mnd_regs(port);
415}
416
417static int msm_startup(struct uart_port *port)
418{
419	struct msm_port *msm_port = UART_TO_MSM(port);
420	unsigned int data, rfr_level;
421	int ret;
422
423	snprintf(msm_port->name, sizeof(msm_port->name),
424		 "msm_serial%d", port->line);
425
426	ret = request_irq(port->irq, msm_irq, IRQF_TRIGGER_HIGH,
427			  msm_port->name, port);
428	if (unlikely(ret))
429		return ret;
430
431	msm_init_clock(port);
432
433	if (likely(port->fifosize > 12))
434		rfr_level = port->fifosize - 12;
435	else
436		rfr_level = port->fifosize;
437
438	/* set automatic RFR level */
439	data = msm_read(port, UART_MR1);
440	data &= ~UART_MR1_AUTO_RFR_LEVEL1;
 
 
 
 
 
 
441	data &= ~UART_MR1_AUTO_RFR_LEVEL0;
442	data |= UART_MR1_AUTO_RFR_LEVEL1 & (rfr_level << 2);
443	data |= UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
444	msm_write(port, data, UART_MR1);
445
446	/* make sure that RXSTALE count is non-zero */
447	data = msm_read(port, UART_IPR);
448	if (unlikely(!data)) {
449		data |= UART_IPR_RXSTALE_LAST;
450		data |= UART_IPR_STALE_LSB;
451		msm_write(port, data, UART_IPR);
452	}
453
454	data = 0;
455	if (!port->cons || (port->cons && !(port->cons->flags & CON_ENABLED))) {
456		msm_write(port, UART_CR_CMD_PROTECTION_EN, UART_CR);
457		msm_reset(port);
458		data = UART_CR_TX_ENABLE;
459	}
460
461	data |= UART_CR_RX_ENABLE;
462	msm_write(port, data, UART_CR);	/* enable TX & RX */
463
464	/* Make sure IPR is not 0 to start with*/
465	if (msm_port->is_uartdm)
466		msm_write(port, UART_IPR_STALE_LSB, UART_IPR);
467
468	/* turn on RX and CTS interrupts */
469	msm_port->imr = UART_IMR_RXLEV | UART_IMR_RXSTALE |
470			UART_IMR_CURRENT_CTS;
471
472	if (msm_port->is_uartdm) {
473		msm_write(port, 0xFFFFFF, UARTDM_DMRX);
474		msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
475		msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
476	}
477
478	msm_write(port, msm_port->imr, UART_IMR);
479	return 0;
480}
481
482static void msm_shutdown(struct uart_port *port)
483{
484	struct msm_port *msm_port = UART_TO_MSM(port);
485
486	msm_port->imr = 0;
487	msm_write(port, 0, UART_IMR); /* disable interrupts */
488
489	clk_disable(msm_port->clk);
 
 
 
490
491	free_irq(port->irq, port);
492}
493
494static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
495			    struct ktermios *old)
496{
 
 
497	unsigned long flags;
498	unsigned int baud, mr;
499
500	spin_lock_irqsave(&port->lock, flags);
501
 
 
 
502	/* calculate and set baud rate */
503	baud = uart_get_baud_rate(port, termios, old, 300, 115200);
504	baud = msm_set_baud_rate(port, baud);
505	if (tty_termios_baud_rate(termios))
506		tty_termios_encode_baud_rate(termios, baud, baud);
507
508	/* calculate parity */
509	mr = msm_read(port, UART_MR2);
510	mr &= ~UART_MR2_PARITY_MODE;
511	if (termios->c_cflag & PARENB) {
512		if (termios->c_cflag & PARODD)
513			mr |= UART_MR2_PARITY_MODE_ODD;
514		else if (termios->c_cflag & CMSPAR)
515			mr |= UART_MR2_PARITY_MODE_SPACE;
516		else
517			mr |= UART_MR2_PARITY_MODE_EVEN;
518	}
519
520	/* calculate bits per char */
521	mr &= ~UART_MR2_BITS_PER_CHAR;
522	switch (termios->c_cflag & CSIZE) {
523	case CS5:
524		mr |= UART_MR2_BITS_PER_CHAR_5;
525		break;
526	case CS6:
527		mr |= UART_MR2_BITS_PER_CHAR_6;
528		break;
529	case CS7:
530		mr |= UART_MR2_BITS_PER_CHAR_7;
531		break;
532	case CS8:
533	default:
534		mr |= UART_MR2_BITS_PER_CHAR_8;
535		break;
536	}
537
538	/* calculate stop bits */
539	mr &= ~(UART_MR2_STOP_BIT_LEN_ONE | UART_MR2_STOP_BIT_LEN_TWO);
540	if (termios->c_cflag & CSTOPB)
541		mr |= UART_MR2_STOP_BIT_LEN_TWO;
542	else
543		mr |= UART_MR2_STOP_BIT_LEN_ONE;
544
545	/* set parity, bits per char, and stop bit */
546	msm_write(port, mr, UART_MR2);
547
548	/* calculate and set hardware flow control */
549	mr = msm_read(port, UART_MR1);
550	mr &= ~(UART_MR1_CTS_CTL | UART_MR1_RX_RDY_CTL);
551	if (termios->c_cflag & CRTSCTS) {
552		mr |= UART_MR1_CTS_CTL;
553		mr |= UART_MR1_RX_RDY_CTL;
554	}
555	msm_write(port, mr, UART_MR1);
556
557	/* Configure status bits to ignore based on termio flags. */
558	port->read_status_mask = 0;
559	if (termios->c_iflag & INPCK)
560		port->read_status_mask |= UART_SR_PAR_FRAME_ERR;
561	if (termios->c_iflag & (BRKINT | PARMRK))
562		port->read_status_mask |= UART_SR_RX_BREAK;
563
564	uart_update_timeout(port, termios->c_cflag, baud);
565
 
 
 
566	spin_unlock_irqrestore(&port->lock, flags);
567}
568
569static const char *msm_type(struct uart_port *port)
570{
571	return "MSM";
572}
573
574static void msm_release_port(struct uart_port *port)
575{
576	struct platform_device *pdev = to_platform_device(port->dev);
577	struct msm_port *msm_port = UART_TO_MSM(port);
578	struct resource *uart_resource;
579	struct resource *gsbi_resource;
580	resource_size_t size;
581
582	uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
583	if (unlikely(!uart_resource))
584		return;
585	size = resource_size(uart_resource);
586
587	release_mem_region(port->mapbase, size);
588	iounmap(port->membase);
589	port->membase = NULL;
590
591	if (msm_port->gsbi_base) {
592		iowrite32(GSBI_PROTOCOL_IDLE, msm_port->gsbi_base +
593			  GSBI_CONTROL);
594
595		gsbi_resource = platform_get_resource(pdev,
596							IORESOURCE_MEM, 1);
597
598		if (unlikely(!gsbi_resource))
599			return;
600
601		size = resource_size(gsbi_resource);
602		release_mem_region(gsbi_resource->start, size);
603		iounmap(msm_port->gsbi_base);
604		msm_port->gsbi_base = NULL;
605	}
606}
607
608static int msm_request_port(struct uart_port *port)
609{
610	struct msm_port *msm_port = UART_TO_MSM(port);
611	struct platform_device *pdev = to_platform_device(port->dev);
612	struct resource *uart_resource;
613	struct resource *gsbi_resource;
614	resource_size_t size;
615	int ret;
616
617	uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
618	if (unlikely(!uart_resource))
619		return -ENXIO;
620
621	size = resource_size(uart_resource);
622
623	if (!request_mem_region(port->mapbase, size, "msm_serial"))
624		return -EBUSY;
625
626	port->membase = ioremap(port->mapbase, size);
627	if (!port->membase) {
628		ret = -EBUSY;
629		goto fail_release_port;
630	}
631
632	gsbi_resource = platform_get_resource(pdev, IORESOURCE_MEM, 1);
633	/* Is this a GSBI-based port? */
634	if (gsbi_resource) {
635		size = resource_size(gsbi_resource);
636
637		if (!request_mem_region(gsbi_resource->start, size,
638						 "msm_serial")) {
639			ret = -EBUSY;
640			goto fail_release_port;
641		}
642
643		msm_port->gsbi_base = ioremap(gsbi_resource->start, size);
644		if (!msm_port->gsbi_base) {
645			ret = -EBUSY;
646			goto fail_release_gsbi;
647		}
648	}
649
650	return 0;
651
652fail_release_gsbi:
653	release_mem_region(gsbi_resource->start, size);
654fail_release_port:
655	release_mem_region(port->mapbase, size);
656	return ret;
657}
658
659static void msm_config_port(struct uart_port *port, int flags)
660{
661	struct msm_port *msm_port = UART_TO_MSM(port);
662	int ret;
 
663	if (flags & UART_CONFIG_TYPE) {
664		port->type = PORT_MSM;
665		ret = msm_request_port(port);
666		if (ret)
667			return;
668	}
669
670	if (msm_port->is_uartdm)
671		iowrite32(GSBI_PROTOCOL_UART, msm_port->gsbi_base +
672			  GSBI_CONTROL);
673}
674
675static int msm_verify_port(struct uart_port *port, struct serial_struct *ser)
676{
677	if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_MSM))
678		return -EINVAL;
679	if (unlikely(port->irq != ser->irq))
680		return -EINVAL;
681	return 0;
682}
683
684static void msm_power(struct uart_port *port, unsigned int state,
685		      unsigned int oldstate)
686{
687	struct msm_port *msm_port = UART_TO_MSM(port);
688
689	switch (state) {
690	case 0:
691		clk_enable(msm_port->clk);
692		if (!IS_ERR(msm_port->pclk))
693			clk_enable(msm_port->pclk);
694		break;
695	case 3:
696		clk_disable(msm_port->clk);
697		if (!IS_ERR(msm_port->pclk))
698			clk_disable(msm_port->pclk);
699		break;
700	default:
701		printk(KERN_ERR "msm_serial: Unknown PM state %d\n", state);
702	}
703}
704
705static struct uart_ops msm_uart_pops = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
706	.tx_empty = msm_tx_empty,
707	.set_mctrl = msm_set_mctrl,
708	.get_mctrl = msm_get_mctrl,
709	.stop_tx = msm_stop_tx,
710	.start_tx = msm_start_tx,
711	.stop_rx = msm_stop_rx,
712	.enable_ms = msm_enable_ms,
713	.break_ctl = msm_break_ctl,
714	.startup = msm_startup,
715	.shutdown = msm_shutdown,
716	.set_termios = msm_set_termios,
717	.type = msm_type,
718	.release_port = msm_release_port,
719	.request_port = msm_request_port,
720	.config_port = msm_config_port,
721	.verify_port = msm_verify_port,
722	.pm = msm_power,
 
 
 
 
723};
724
725static struct msm_port msm_uart_ports[] = {
726	{
727		.uart = {
728			.iotype = UPIO_MEM,
729			.ops = &msm_uart_pops,
730			.flags = UPF_BOOT_AUTOCONF,
731			.fifosize = 64,
732			.line = 0,
733		},
734	},
735	{
736		.uart = {
737			.iotype = UPIO_MEM,
738			.ops = &msm_uart_pops,
739			.flags = UPF_BOOT_AUTOCONF,
740			.fifosize = 64,
741			.line = 1,
742		},
743	},
744	{
745		.uart = {
746			.iotype = UPIO_MEM,
747			.ops = &msm_uart_pops,
748			.flags = UPF_BOOT_AUTOCONF,
749			.fifosize = 64,
750			.line = 2,
751		},
752	},
753};
754
755#define UART_NR	ARRAY_SIZE(msm_uart_ports)
756
757static inline struct uart_port *get_port_from_line(unsigned int line)
758{
759	return &msm_uart_ports[line].uart;
760}
761
762#ifdef CONFIG_SERIAL_MSM_CONSOLE
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
763
764static void msm_console_putchar(struct uart_port *port, int c)
765{
766	struct msm_port *msm_port = UART_TO_MSM(port);
767
768	if (msm_port->is_uartdm)
769		reset_dm_count(port);
 
770
771	while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
772		;
773	msm_write(port, c, msm_port->is_uartdm ? UARTDM_TF : UART_TF);
774}
775
776static void msm_console_write(struct console *co, const char *s,
777			      unsigned int count)
778{
779	struct uart_port *port;
780	struct msm_port *msm_port;
781
782	BUG_ON(co->index < 0 || co->index >= UART_NR);
783
784	port = get_port_from_line(co->index);
785	msm_port = UART_TO_MSM(port);
786
787	spin_lock(&port->lock);
788	uart_console_write(port, s, count, msm_console_putchar);
789	spin_unlock(&port->lock);
790}
791
792static int __init msm_console_setup(struct console *co, char *options)
793{
794	struct uart_port *port;
795	struct msm_port *msm_port;
796	int baud, flow, bits, parity;
 
 
797
798	if (unlikely(co->index >= UART_NR || co->index < 0))
799		return -ENXIO;
800
801	port = get_port_from_line(co->index);
802	msm_port = UART_TO_MSM(port);
803
804	if (unlikely(!port->membase))
805		return -ENXIO;
806
807	msm_init_clock(port);
808
809	if (options)
810		uart_parse_options(options, &baud, &parity, &bits, &flow);
811
812	bits = 8;
813	parity = 'n';
814	flow = 'n';
815	msm_write(port, UART_MR2_BITS_PER_CHAR_8 | UART_MR2_STOP_BIT_LEN_ONE,
816		  UART_MR2);	/* 8N1 */
817
818	if (baud < 300 || baud > 115200)
819		baud = 115200;
820	msm_set_baud_rate(port, baud);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
821
822	msm_reset(port);
 
 
 
823
824	if (msm_port->is_uartdm) {
825		msm_write(port, UART_CR_CMD_PROTECTION_EN, UART_CR);
826		msm_write(port, UART_CR_TX_ENABLE, UART_CR);
827	}
828
829	printk(KERN_INFO "msm_serial: console setup on port #%d\n", port->line);
 
 
 
 
 
830
831	return uart_set_options(port, co, baud, parity, bits, flow);
 
832}
 
 
833
834static struct uart_driver msm_uart_driver;
835
836static struct console msm_console = {
837	.name = "ttyMSM",
838	.write = msm_console_write,
839	.device = uart_console_device,
840	.setup = msm_console_setup,
841	.flags = CON_PRINTBUFFER,
842	.index = -1,
843	.data = &msm_uart_driver,
844};
845
846#define MSM_CONSOLE	(&msm_console)
847
848#else
849#define MSM_CONSOLE	NULL
850#endif
851
852static struct uart_driver msm_uart_driver = {
853	.owner = THIS_MODULE,
854	.driver_name = "msm_serial",
855	.dev_name = "ttyMSM",
856	.nr = UART_NR,
857	.cons = MSM_CONSOLE,
858};
859
860static atomic_t msm_uart_next_id = ATOMIC_INIT(0);
861
862static int __init msm_serial_probe(struct platform_device *pdev)
 
 
 
 
 
 
 
 
863{
864	struct msm_port *msm_port;
865	struct resource *resource;
866	struct uart_port *port;
867	int irq;
 
868
869	if (pdev->id == -1)
870		pdev->id = atomic_inc_return(&msm_uart_next_id) - 1;
 
 
 
 
 
871
872	if (unlikely(pdev->id < 0 || pdev->id >= UART_NR))
873		return -ENXIO;
874
875	printk(KERN_INFO "msm_serial: detected port #%d\n", pdev->id);
876
877	port = get_port_from_line(pdev->id);
878	port->dev = &pdev->dev;
879	msm_port = UART_TO_MSM(port);
880
881	if (platform_get_resource(pdev, IORESOURCE_MEM, 1))
882		msm_port->is_uartdm = 1;
 
883	else
884		msm_port->is_uartdm = 0;
885
 
 
 
 
886	if (msm_port->is_uartdm) {
887		msm_port->clk = clk_get(&pdev->dev, "gsbi_uart_clk");
888		msm_port->pclk = clk_get(&pdev->dev, "gsbi_pclk");
889	} else {
890		msm_port->clk = clk_get(&pdev->dev, "uart_clk");
891		msm_port->pclk = ERR_PTR(-ENOENT);
892	}
893
894	if (unlikely(IS_ERR(msm_port->clk) || (IS_ERR(msm_port->pclk) &&
895					       msm_port->is_uartdm)))
896			return PTR_ERR(msm_port->clk);
897
898	if (msm_port->is_uartdm)
899		clk_set_rate(msm_port->clk, 7372800);
900
901	port->uartclk = clk_get_rate(msm_port->clk);
902	printk(KERN_INFO "uartclk = %d\n", port->uartclk);
903
904
905	resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
906	if (unlikely(!resource))
907		return -ENXIO;
908	port->mapbase = resource->start;
909
910	irq = platform_get_irq(pdev, 0);
911	if (unlikely(irq < 0))
912		return -ENXIO;
913	port->irq = irq;
 
914
915	platform_set_drvdata(pdev, port);
916
917	return uart_add_one_port(&msm_uart_driver, port);
918}
919
920static int __devexit msm_serial_remove(struct platform_device *pdev)
921{
922	struct msm_port *msm_port = platform_get_drvdata(pdev);
923
924	clk_put(msm_port->clk);
925
926	return 0;
927}
928
929static struct of_device_id msm_match_table[] = {
930	{ .compatible = "qcom,msm-uart" },
 
931	{}
932};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
933
934static struct platform_driver msm_platform_driver = {
935	.remove = msm_serial_remove,
 
936	.driver = {
937		.name = "msm_serial",
938		.owner = THIS_MODULE,
939		.of_match_table = msm_match_table,
940	},
941};
942
943static int __init msm_serial_init(void)
944{
945	int ret;
946
947	ret = uart_register_driver(&msm_uart_driver);
948	if (unlikely(ret))
949		return ret;
950
951	ret = platform_driver_probe(&msm_platform_driver, msm_serial_probe);
952	if (unlikely(ret))
953		uart_unregister_driver(&msm_uart_driver);
954
955	printk(KERN_INFO "msm_serial: driver initialized\n");
956
957	return ret;
958}
959
960static void __exit msm_serial_exit(void)
961{
962#ifdef CONFIG_SERIAL_MSM_CONSOLE
963	unregister_console(&msm_console);
964#endif
965	platform_driver_unregister(&msm_platform_driver);
966	uart_unregister_driver(&msm_uart_driver);
967}
968
969module_init(msm_serial_init);
970module_exit(msm_serial_exit);
971
972MODULE_AUTHOR("Robert Love <rlove@google.com>");
973MODULE_DESCRIPTION("Driver for msm7x serial device");
974MODULE_LICENSE("GPL");