2 * Driver for Motorola IMX serial ports
4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
6 * Author: Sascha Hauer <sascha@saschahauer.de>
7 * Copyright (C) 2004 Pengutronix
9 * Copyright (C) 2009 emlix GmbH
10 * Author: Fabian Godehardt (added IrDA support for iMX)
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 * [29-Mar-2005] Mike Lee
27 * Added hardware handshake
30 #if defined(CONFIG_SERIAL_IMX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
34 #include <linux/module.h>
35 #include <linux/ioport.h>
36 #include <linux/init.h>
37 #include <linux/console.h>
38 #include <linux/sysrq.h>
39 #include <linux/platform_device.h>
40 #include <linux/tty.h>
41 #include <linux/tty_flip.h>
42 #include <linux/serial_core.h>
43 #include <linux/serial.h>
44 #include <linux/clk.h>
45 #include <linux/delay.h>
46 #include <linux/rational.h>
47 #include <linux/slab.h>
49 #include <linux/of_device.h>
51 #include <linux/dma-mapping.h>
54 #include <linux/platform_data/serial-imx.h>
55 #include <linux/platform_data/dma-imx.h>
57 /* Register definitions */
58 #define URXD0 0x0 /* Receiver Register */
59 #define URTX0 0x40 /* Transmitter Register */
60 #define UCR1 0x80 /* Control Register 1 */
61 #define UCR2 0x84 /* Control Register 2 */
62 #define UCR3 0x88 /* Control Register 3 */
63 #define UCR4 0x8c /* Control Register 4 */
64 #define UFCR 0x90 /* FIFO Control Register */
65 #define USR1 0x94 /* Status Register 1 */
66 #define USR2 0x98 /* Status Register 2 */
67 #define UESC 0x9c /* Escape Character Register */
68 #define UTIM 0xa0 /* Escape Timer Register */
69 #define UBIR 0xa4 /* BRM Incremental Register */
70 #define UBMR 0xa8 /* BRM Modulator Register */
71 #define UBRC 0xac /* Baud Rate Count Register */
72 #define IMX21_ONEMS 0xb0 /* One Millisecond register */
73 #define IMX1_UTS 0xd0 /* UART Test Register on i.mx1 */
74 #define IMX21_UTS 0xb4 /* UART Test Register on all other i.mx*/
76 /* UART Control Register Bit Fields.*/
77 #define URXD_CHARRDY (1<<15)
78 #define URXD_ERR (1<<14)
79 #define URXD_OVRRUN (1<<13)
80 #define URXD_FRMERR (1<<12)
81 #define URXD_BRK (1<<11)
82 #define URXD_PRERR (1<<10)
83 #define URXD_RX_DATA (0xFF<<0)
84 #define UCR1_ADEN (1<<15) /* Auto detect interrupt */
85 #define UCR1_ADBR (1<<14) /* Auto detect baud rate */
86 #define UCR1_TRDYEN (1<<13) /* Transmitter ready interrupt enable */
87 #define UCR1_IDEN (1<<12) /* Idle condition interrupt */
88 #define UCR1_ICD_REG(x) (((x) & 3) << 10) /* idle condition detect */
89 #define UCR1_RRDYEN (1<<9) /* Recv ready interrupt enable */
90 #define UCR1_RDMAEN (1<<8) /* Recv ready DMA enable */
91 #define UCR1_IREN (1<<7) /* Infrared interface enable */
92 #define UCR1_TXMPTYEN (1<<6) /* Transimitter empty interrupt enable */
93 #define UCR1_RTSDEN (1<<5) /* RTS delta interrupt enable */
94 #define UCR1_SNDBRK (1<<4) /* Send break */
95 #define UCR1_TDMAEN (1<<3) /* Transmitter ready DMA enable */
96 #define IMX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, i.mx1 only */
97 #define UCR1_ATDMAEN (1<<2) /* Aging DMA Timer Enable */
98 #define UCR1_DOZE (1<<1) /* Doze */
99 #define UCR1_UARTEN (1<<0) /* UART enabled */
100 #define UCR2_ESCI (1<<15) /* Escape seq interrupt enable */
101 #define UCR2_IRTS (1<<14) /* Ignore RTS pin */
102 #define UCR2_CTSC (1<<13) /* CTS pin control */
103 #define UCR2_CTS (1<<12) /* Clear to send */
104 #define UCR2_ESCEN (1<<11) /* Escape enable */
105 #define UCR2_PREN (1<<8) /* Parity enable */
106 #define UCR2_PROE (1<<7) /* Parity odd/even */
107 #define UCR2_STPB (1<<6) /* Stop */
108 #define UCR2_WS (1<<5) /* Word size */
109 #define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */
110 #define UCR2_ATEN (1<<3) /* Aging Timer Enable */
111 #define UCR2_TXEN (1<<2) /* Transmitter enabled */
112 #define UCR2_RXEN (1<<1) /* Receiver enabled */
113 #define UCR2_SRST (1<<0) /* SW reset */
114 #define UCR3_DTREN (1<<13) /* DTR interrupt enable */
115 #define UCR3_PARERREN (1<<12) /* Parity enable */
116 #define UCR3_FRAERREN (1<<11) /* Frame error interrupt enable */
117 #define UCR3_DSR (1<<10) /* Data set ready */
118 #define UCR3_DCD (1<<9) /* Data carrier detect */
119 #define UCR3_RI (1<<8) /* Ring indicator */
120 #define UCR3_ADNIMP (1<<7) /* Autobaud Detection Not Improved */
121 #define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */
122 #define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */
123 #define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */
124 #define IMX21_UCR3_RXDMUXSEL (1<<2) /* RXD Muxed Input Select */
125 #define UCR3_INVT (1<<1) /* Inverted Infrared transmission */
126 #define UCR3_BPEN (1<<0) /* Preset registers enable */
127 #define UCR4_CTSTL_SHF 10 /* CTS trigger level shift */
128 #define UCR4_CTSTL_MASK 0x3F /* CTS trigger is 6 bits wide */
129 #define UCR4_INVR (1<<9) /* Inverted infrared reception */
130 #define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */
131 #define UCR4_WKEN (1<<7) /* Wake interrupt enable */
132 #define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */
133 #define UCR4_IDDMAEN (1<<6) /* DMA IDLE Condition Detected */
134 #define UCR4_IRSC (1<<5) /* IR special case */
135 #define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */
136 #define UCR4_BKEN (1<<2) /* Break condition interrupt enable */
137 #define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */
138 #define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */
139 #define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */
140 #define UFCR_DCEDTE (1<<6) /* DCE/DTE mode select */
141 #define UFCR_RFDIV (7<<7) /* Reference freq divider mask */
142 #define UFCR_RFDIV_REG(x) (((x) < 7 ? 6 - (x) : 6) << 7)
143 #define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */
144 #define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */
145 #define USR1_RTSS (1<<14) /* RTS pin status */
146 #define USR1_TRDY (1<<13) /* Transmitter ready interrupt/dma flag */
147 #define USR1_RTSD (1<<12) /* RTS delta */
148 #define USR1_ESCF (1<<11) /* Escape seq interrupt flag */
149 #define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */
150 #define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */
151 #define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */
152 #define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */
153 #define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */
154 #define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */
155 #define USR2_ADET (1<<15) /* Auto baud rate detect complete */
156 #define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */
157 #define USR2_DTRF (1<<13) /* DTR edge interrupt flag */
158 #define USR2_IDLE (1<<12) /* Idle condition */
159 #define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */
160 #define USR2_WAKE (1<<7) /* Wake */
161 #define USR2_RTSF (1<<4) /* RTS edge interrupt flag */
162 #define USR2_TXDC (1<<3) /* Transmitter complete */
163 #define USR2_BRCD (1<<2) /* Break condition */
164 #define USR2_ORE (1<<1) /* Overrun error */
165 #define USR2_RDR (1<<0) /* Recv data ready */
166 #define UTS_FRCPERR (1<<13) /* Force parity error */
167 #define UTS_LOOP (1<<12) /* Loop tx and rx */
168 #define UTS_TXEMPTY (1<<6) /* TxFIFO empty */
169 #define UTS_RXEMPTY (1<<5) /* RxFIFO empty */
170 #define UTS_TXFULL (1<<4) /* TxFIFO full */
171 #define UTS_RXFULL (1<<3) /* RxFIFO full */
172 #define UTS_SOFTRST (1<<0) /* Software reset */
174 /* We've been assigned a range on the "Low-density serial ports" major */
175 #define SERIAL_IMX_MAJOR 207
176 #define MINOR_START 16
177 #define DEV_NAME "ttymxc"
180 * This determines how often we check the modem status signals
181 * for any change. They generally aren't connected to an IRQ
182 * so we have to poll them. We also check immediately before
183 * filling the TX fifo incase CTS has been dropped.
185 #define MCTRL_TIMEOUT (250*HZ/1000)
187 #define DRIVER_NAME "IMX-uart"
191 /* i.mx21 type uart runs on all i.mx except i.mx1 */
198 /* device type dependent stuff */
199 struct imx_uart_data {
201 enum imx_uart_type devtype;
205 struct uart_port port;
206 struct timer_list timer;
207 unsigned int old_status;
208 int txirq, rxirq, rtsirq;
209 unsigned int have_rtscts:1;
210 unsigned int dte_mode:1;
211 unsigned int use_irda:1;
212 unsigned int irda_inv_rx:1;
213 unsigned int irda_inv_tx:1;
214 unsigned short trcv_delay; /* transceiver delay */
217 const struct imx_uart_data *devdata;
220 unsigned int dma_is_inited:1;
221 unsigned int dma_is_enabled:1;
222 unsigned int dma_is_rxing:1;
223 unsigned int dma_is_txing:1;
224 struct dma_chan *dma_chan_rx, *dma_chan_tx;
225 struct scatterlist rx_sgl, tx_sgl[2];
227 unsigned int tx_bytes;
228 unsigned int dma_tx_nents;
229 wait_queue_head_t dma_wait;
232 struct imx_port_ucrs {
239 #define USE_IRDA(sport) ((sport)->use_irda)
241 #define USE_IRDA(sport) (0)
244 static struct imx_uart_data imx_uart_devdata[] = {
247 .devtype = IMX1_UART,
250 .uts_reg = IMX21_UTS,
251 .devtype = IMX21_UART,
254 .uts_reg = IMX21_UTS,
255 .devtype = IMX6Q_UART,
259 static struct platform_device_id imx_uart_devtype[] = {
262 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX1_UART],
264 .name = "imx21-uart",
265 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX21_UART],
267 .name = "imx6q-uart",
268 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX6Q_UART],
273 MODULE_DEVICE_TABLE(platform, imx_uart_devtype);
275 static struct of_device_id imx_uart_dt_ids[] = {
276 { .compatible = "fsl,imx6q-uart", .data = &imx_uart_devdata[IMX6Q_UART], },
277 { .compatible = "fsl,imx1-uart", .data = &imx_uart_devdata[IMX1_UART], },
278 { .compatible = "fsl,imx21-uart", .data = &imx_uart_devdata[IMX21_UART], },
281 MODULE_DEVICE_TABLE(of, imx_uart_dt_ids);
283 static inline unsigned uts_reg(struct imx_port *sport)
285 return sport->devdata->uts_reg;
288 static inline int is_imx1_uart(struct imx_port *sport)
290 return sport->devdata->devtype == IMX1_UART;
293 static inline int is_imx21_uart(struct imx_port *sport)
295 return sport->devdata->devtype == IMX21_UART;
298 static inline int is_imx6q_uart(struct imx_port *sport)
300 return sport->devdata->devtype == IMX6Q_UART;
303 * Save and restore functions for UCR1, UCR2 and UCR3 registers
305 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_IMX_CONSOLE)
306 static void imx_port_ucrs_save(struct uart_port *port,
307 struct imx_port_ucrs *ucr)
309 /* save control registers */
310 ucr->ucr1 = readl(port->membase + UCR1);
311 ucr->ucr2 = readl(port->membase + UCR2);
312 ucr->ucr3 = readl(port->membase + UCR3);
315 static void imx_port_ucrs_restore(struct uart_port *port,
316 struct imx_port_ucrs *ucr)
318 /* restore control registers */
319 writel(ucr->ucr1, port->membase + UCR1);
320 writel(ucr->ucr2, port->membase + UCR2);
321 writel(ucr->ucr3, port->membase + UCR3);
326 * Handle any change of modem status signal since we were last called.
328 static void imx_mctrl_check(struct imx_port *sport)
330 unsigned int status, changed;
332 status = sport->port.ops->get_mctrl(&sport->port);
333 changed = status ^ sport->old_status;
338 sport->old_status = status;
340 if (changed & TIOCM_RI)
341 sport->port.icount.rng++;
342 if (changed & TIOCM_DSR)
343 sport->port.icount.dsr++;
344 if (changed & TIOCM_CAR)
345 uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
346 if (changed & TIOCM_CTS)
347 uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
349 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
353 * This is our per-port timeout handler, for checking the
354 * modem status signals.
356 static void imx_timeout(unsigned long data)
358 struct imx_port *sport = (struct imx_port *)data;
361 if (sport->port.state) {
362 spin_lock_irqsave(&sport->port.lock, flags);
363 imx_mctrl_check(sport);
364 spin_unlock_irqrestore(&sport->port.lock, flags);
366 mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
371 * interrupts disabled on entry
373 static void imx_stop_tx(struct uart_port *port)
375 struct imx_port *sport = (struct imx_port *)port;
378 if (USE_IRDA(sport)) {
379 /* half duplex - wait for end of transmission */
382 !(readl(sport->port.membase + USR2) & USR2_TXDC)) {
387 * irda transceiver - wait a bit more to avoid
388 * cutoff, hardware dependent
390 udelay(sport->trcv_delay);
393 * half duplex - reactivate receive mode,
394 * flush receive pipe echo crap
396 if (readl(sport->port.membase + USR2) & USR2_TXDC) {
397 temp = readl(sport->port.membase + UCR1);
398 temp &= ~(UCR1_TXMPTYEN | UCR1_TRDYEN);
399 writel(temp, sport->port.membase + UCR1);
401 temp = readl(sport->port.membase + UCR4);
402 temp &= ~(UCR4_TCEN);
403 writel(temp, sport->port.membase + UCR4);
405 while (readl(sport->port.membase + URXD0) &
409 temp = readl(sport->port.membase + UCR1);
411 writel(temp, sport->port.membase + UCR1);
413 temp = readl(sport->port.membase + UCR4);
415 writel(temp, sport->port.membase + UCR4);
421 * We are maybe in the SMP context, so if the DMA TX thread is running
422 * on other cpu, we have to wait for it to finish.
424 if (sport->dma_is_enabled && sport->dma_is_txing)
427 temp = readl(sport->port.membase + UCR1);
428 writel(temp & ~UCR1_TXMPTYEN, sport->port.membase + UCR1);
432 * interrupts disabled on entry
434 static void imx_stop_rx(struct uart_port *port)
436 struct imx_port *sport = (struct imx_port *)port;
439 if (sport->dma_is_enabled && sport->dma_is_rxing) {
440 if (sport->port.suspended) {
441 dmaengine_terminate_all(sport->dma_chan_rx);
442 sport->dma_is_rxing = 0;
448 temp = readl(sport->port.membase + UCR2);
449 writel(temp & ~UCR2_RXEN, sport->port.membase + UCR2);
451 /* disable the `Receiver Ready Interrrupt` */
452 temp = readl(sport->port.membase + UCR1);
453 writel(temp & ~UCR1_RRDYEN, sport->port.membase + UCR1);
457 * Set the modem control timer to fire immediately.
459 static void imx_enable_ms(struct uart_port *port)
461 struct imx_port *sport = (struct imx_port *)port;
463 mod_timer(&sport->timer, jiffies);
466 static inline void imx_transmit_buffer(struct imx_port *sport)
468 struct circ_buf *xmit = &sport->port.state->xmit;
470 if (sport->port.x_char) {
472 writel(sport->port.x_char, sport->port.membase + URTX0);
476 if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
477 imx_stop_tx(&sport->port);
481 while (!uart_circ_empty(xmit) &&
482 !(readl(sport->port.membase + uts_reg(sport)) & UTS_TXFULL)) {
483 /* send xmit->buf[xmit->tail]
484 * out the port here */
485 writel(xmit->buf[xmit->tail], sport->port.membase + URTX0);
486 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
487 sport->port.icount.tx++;
490 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
491 uart_write_wakeup(&sport->port);
493 if (uart_circ_empty(xmit))
494 imx_stop_tx(&sport->port);
497 static void dma_tx_callback(void *data)
499 struct imx_port *sport = data;
500 struct scatterlist *sgl = &sport->tx_sgl[0];
501 struct circ_buf *xmit = &sport->port.state->xmit;
504 dma_unmap_sg(sport->port.dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
506 sport->dma_is_txing = 0;
508 /* update the stat */
509 spin_lock_irqsave(&sport->port.lock, flags);
510 xmit->tail = (xmit->tail + sport->tx_bytes) & (UART_XMIT_SIZE - 1);
511 sport->port.icount.tx += sport->tx_bytes;
512 spin_unlock_irqrestore(&sport->port.lock, flags);
514 dev_dbg(sport->port.dev, "we finish the TX DMA.\n");
516 uart_write_wakeup(&sport->port);
518 if (waitqueue_active(&sport->dma_wait)) {
519 wake_up(&sport->dma_wait);
520 dev_dbg(sport->port.dev, "exit in %s.\n", __func__);
525 static void imx_dma_tx(struct imx_port *sport)
527 struct circ_buf *xmit = &sport->port.state->xmit;
528 struct scatterlist *sgl = sport->tx_sgl;
529 struct dma_async_tx_descriptor *desc;
530 struct dma_chan *chan = sport->dma_chan_tx;
531 struct device *dev = sport->port.dev;
532 enum dma_status status;
535 status = dmaengine_tx_status(chan, (dma_cookie_t)0, NULL);
536 if (DMA_IN_PROGRESS == status)
539 sport->tx_bytes = uart_circ_chars_pending(xmit);
541 if (xmit->tail > xmit->head && xmit->head > 0) {
542 sport->dma_tx_nents = 2;
543 sg_init_table(sgl, 2);
544 sg_set_buf(sgl, xmit->buf + xmit->tail,
545 UART_XMIT_SIZE - xmit->tail);
546 sg_set_buf(sgl + 1, xmit->buf, xmit->head);
548 sport->dma_tx_nents = 1;
549 sg_init_one(sgl, xmit->buf + xmit->tail, sport->tx_bytes);
552 ret = dma_map_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
554 dev_err(dev, "DMA mapping error for TX.\n");
557 desc = dmaengine_prep_slave_sg(chan, sgl, sport->dma_tx_nents,
558 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
560 dev_err(dev, "We cannot prepare for the TX slave dma!\n");
563 desc->callback = dma_tx_callback;
564 desc->callback_param = sport;
566 dev_dbg(dev, "TX: prepare to send %lu bytes by DMA.\n",
567 uart_circ_chars_pending(xmit));
569 sport->dma_is_txing = 1;
570 dmaengine_submit(desc);
571 dma_async_issue_pending(chan);
576 * interrupts disabled on entry
578 static void imx_start_tx(struct uart_port *port)
580 struct imx_port *sport = (struct imx_port *)port;
583 if (USE_IRDA(sport)) {
584 /* half duplex in IrDA mode; have to disable receive mode */
585 temp = readl(sport->port.membase + UCR4);
586 temp &= ~(UCR4_DREN);
587 writel(temp, sport->port.membase + UCR4);
589 temp = readl(sport->port.membase + UCR1);
590 temp &= ~(UCR1_RRDYEN);
591 writel(temp, sport->port.membase + UCR1);
593 /* Clear any pending ORE flag before enabling interrupt */
594 temp = readl(sport->port.membase + USR2);
595 writel(temp | USR2_ORE, sport->port.membase + USR2);
597 temp = readl(sport->port.membase + UCR4);
599 writel(temp, sport->port.membase + UCR4);
601 if (!sport->dma_is_enabled) {
602 temp = readl(sport->port.membase + UCR1);
603 writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
606 if (USE_IRDA(sport)) {
607 temp = readl(sport->port.membase + UCR1);
609 writel(temp, sport->port.membase + UCR1);
611 temp = readl(sport->port.membase + UCR4);
613 writel(temp, sport->port.membase + UCR4);
616 if (sport->dma_is_enabled) {
617 /* FIXME: port->x_char must be transmitted if != 0 */
618 if (!uart_circ_empty(&port->state->xmit) &&
619 !uart_tx_stopped(port))
624 if (readl(sport->port.membase + uts_reg(sport)) & UTS_TXEMPTY)
625 imx_transmit_buffer(sport);
628 static irqreturn_t imx_rtsint(int irq, void *dev_id)
630 struct imx_port *sport = dev_id;
634 spin_lock_irqsave(&sport->port.lock, flags);
636 writel(USR1_RTSD, sport->port.membase + USR1);
637 val = readl(sport->port.membase + USR1) & USR1_RTSS;
638 uart_handle_cts_change(&sport->port, !!val);
639 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
641 spin_unlock_irqrestore(&sport->port.lock, flags);
645 static irqreturn_t imx_txint(int irq, void *dev_id)
647 struct imx_port *sport = dev_id;
650 spin_lock_irqsave(&sport->port.lock, flags);
651 imx_transmit_buffer(sport);
652 spin_unlock_irqrestore(&sport->port.lock, flags);
656 static irqreturn_t imx_rxint(int irq, void *dev_id)
658 struct imx_port *sport = dev_id;
659 unsigned int rx, flg, ignored = 0;
660 struct tty_port *port = &sport->port.state->port;
661 unsigned long flags, temp;
663 spin_lock_irqsave(&sport->port.lock, flags);
665 while (readl(sport->port.membase + USR2) & USR2_RDR) {
667 sport->port.icount.rx++;
669 rx = readl(sport->port.membase + URXD0);
671 temp = readl(sport->port.membase + USR2);
672 if (temp & USR2_BRCD) {
673 writel(USR2_BRCD, sport->port.membase + USR2);
674 if (uart_handle_break(&sport->port))
678 if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
681 if (unlikely(rx & URXD_ERR)) {
683 sport->port.icount.brk++;
684 else if (rx & URXD_PRERR)
685 sport->port.icount.parity++;
686 else if (rx & URXD_FRMERR)
687 sport->port.icount.frame++;
688 if (rx & URXD_OVRRUN)
689 sport->port.icount.overrun++;
691 if (rx & sport->port.ignore_status_mask) {
697 rx &= sport->port.read_status_mask;
701 else if (rx & URXD_PRERR)
703 else if (rx & URXD_FRMERR)
705 if (rx & URXD_OVRRUN)
709 sport->port.sysrq = 0;
713 tty_insert_flip_char(port, rx, flg);
717 spin_unlock_irqrestore(&sport->port.lock, flags);
718 tty_flip_buffer_push(port);
722 static int start_rx_dma(struct imx_port *sport);
724 * If the RXFIFO is filled with some data, and then we
725 * arise a DMA operation to receive them.
727 static void imx_dma_rxint(struct imx_port *sport)
731 temp = readl(sport->port.membase + USR2);
732 if ((temp & USR2_RDR) && !sport->dma_is_rxing) {
733 sport->dma_is_rxing = 1;
735 /* disable the `Recerver Ready Interrrupt` */
736 temp = readl(sport->port.membase + UCR1);
737 temp &= ~(UCR1_RRDYEN);
738 writel(temp, sport->port.membase + UCR1);
740 /* tell the DMA to receive the data. */
745 static irqreturn_t imx_int(int irq, void *dev_id)
747 struct imx_port *sport = dev_id;
751 sts = readl(sport->port.membase + USR1);
753 if (sts & USR1_RRDY) {
754 if (sport->dma_is_enabled)
755 imx_dma_rxint(sport);
757 imx_rxint(irq, dev_id);
760 if (sts & USR1_TRDY &&
761 readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN)
762 imx_txint(irq, dev_id);
765 imx_rtsint(irq, dev_id);
767 if (sts & USR1_AWAKE)
768 writel(USR1_AWAKE, sport->port.membase + USR1);
770 sts2 = readl(sport->port.membase + USR2);
771 if (sts2 & USR2_ORE) {
772 dev_err(sport->port.dev, "Rx FIFO overrun\n");
773 sport->port.icount.overrun++;
774 writel(sts2 | USR2_ORE, sport->port.membase + USR2);
781 * Return TIOCSER_TEMT when transmitter is not busy.
783 static unsigned int imx_tx_empty(struct uart_port *port)
785 struct imx_port *sport = (struct imx_port *)port;
788 ret = (readl(sport->port.membase + USR2) & USR2_TXDC) ? TIOCSER_TEMT : 0;
790 /* If the TX DMA is working, return 0. */
791 if (sport->dma_is_enabled && sport->dma_is_txing)
798 * We have a modem side uart, so the meanings of RTS and CTS are inverted.
800 static unsigned int imx_get_mctrl(struct uart_port *port)
802 struct imx_port *sport = (struct imx_port *)port;
803 unsigned int tmp = TIOCM_DSR | TIOCM_CAR;
805 if (readl(sport->port.membase + USR1) & USR1_RTSS)
808 if (readl(sport->port.membase + UCR2) & UCR2_CTS)
811 if (readl(sport->port.membase + uts_reg(sport)) & UTS_LOOP)
817 static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
819 struct imx_port *sport = (struct imx_port *)port;
822 temp = readl(sport->port.membase + UCR2) & ~(UCR2_CTS | UCR2_CTSC);
823 if (mctrl & TIOCM_RTS)
824 temp |= UCR2_CTS | UCR2_CTSC;
826 writel(temp, sport->port.membase + UCR2);
828 temp = readl(sport->port.membase + uts_reg(sport)) & ~UTS_LOOP;
829 if (mctrl & TIOCM_LOOP)
831 writel(temp, sport->port.membase + uts_reg(sport));
835 * Interrupts always disabled.
837 static void imx_break_ctl(struct uart_port *port, int break_state)
839 struct imx_port *sport = (struct imx_port *)port;
840 unsigned long flags, temp;
842 spin_lock_irqsave(&sport->port.lock, flags);
844 temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK;
846 if (break_state != 0)
849 writel(temp, sport->port.membase + UCR1);
851 spin_unlock_irqrestore(&sport->port.lock, flags);
854 #define TXTL 2 /* reset default */
855 #define RXTL 1 /* reset default */
857 static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
861 /* set receiver / transmitter trigger level */
862 val = readl(sport->port.membase + UFCR) & (UFCR_RFDIV | UFCR_DCEDTE);
863 val |= TXTL << UFCR_TXTL_SHF | RXTL;
864 writel(val, sport->port.membase + UFCR);
868 #define RX_BUF_SIZE (PAGE_SIZE)
869 static void imx_rx_dma_done(struct imx_port *sport)
873 /* Enable this interrupt when the RXFIFO is empty. */
874 temp = readl(sport->port.membase + UCR1);
876 writel(temp, sport->port.membase + UCR1);
878 sport->dma_is_rxing = 0;
880 /* Is the shutdown waiting for us? */
881 if (waitqueue_active(&sport->dma_wait))
882 wake_up(&sport->dma_wait);
886 * There are three kinds of RX DMA interrupts(such as in the MX6Q):
887 * [1] the RX DMA buffer is full.
888 * [2] the Aging timer expires(wait for 8 bytes long)
889 * [3] the Idle Condition Detect(enabled the UCR4_IDDMAEN).
891 * The [2] is trigger when a character was been sitting in the FIFO
892 * meanwhile [3] can wait for 32 bytes long when the RX line is
893 * on IDLE state and RxFIFO is empty.
895 static void dma_rx_callback(void *data)
897 struct imx_port *sport = data;
898 struct dma_chan *chan = sport->dma_chan_rx;
899 struct scatterlist *sgl = &sport->rx_sgl;
900 struct tty_port *port = &sport->port.state->port;
901 struct dma_tx_state state;
902 enum dma_status status;
906 dma_unmap_sg(sport->port.dev, sgl, 1, DMA_FROM_DEVICE);
908 status = dmaengine_tx_status(chan, (dma_cookie_t)0, &state);
909 count = RX_BUF_SIZE - state.residue;
910 dev_dbg(sport->port.dev, "We get %d bytes.\n", count);
913 tty_insert_flip_string(port, sport->rx_buf, count);
914 tty_flip_buffer_push(port);
918 imx_rx_dma_done(sport);
921 static int start_rx_dma(struct imx_port *sport)
923 struct scatterlist *sgl = &sport->rx_sgl;
924 struct dma_chan *chan = sport->dma_chan_rx;
925 struct device *dev = sport->port.dev;
926 struct dma_async_tx_descriptor *desc;
929 sg_init_one(sgl, sport->rx_buf, RX_BUF_SIZE);
930 ret = dma_map_sg(dev, sgl, 1, DMA_FROM_DEVICE);
932 dev_err(dev, "DMA mapping error for RX.\n");
935 desc = dmaengine_prep_slave_sg(chan, sgl, 1, DMA_DEV_TO_MEM,
938 dev_err(dev, "We cannot prepare for the RX slave dma!\n");
941 desc->callback = dma_rx_callback;
942 desc->callback_param = sport;
944 dev_dbg(dev, "RX: prepare for the DMA.\n");
945 dmaengine_submit(desc);
946 dma_async_issue_pending(chan);
950 static void imx_uart_dma_exit(struct imx_port *sport)
952 if (sport->dma_chan_rx) {
953 dma_release_channel(sport->dma_chan_rx);
954 sport->dma_chan_rx = NULL;
956 kfree(sport->rx_buf);
957 sport->rx_buf = NULL;
960 if (sport->dma_chan_tx) {
961 dma_release_channel(sport->dma_chan_tx);
962 sport->dma_chan_tx = NULL;
965 sport->dma_is_inited = 0;
968 static int imx_uart_dma_init(struct imx_port *sport)
970 struct dma_slave_config slave_config = {};
971 struct device *dev = sport->port.dev;
974 /* Prepare for RX : */
975 sport->dma_chan_rx = dma_request_slave_channel(dev, "rx");
976 if (!sport->dma_chan_rx) {
977 dev_dbg(dev, "cannot get the DMA channel.\n");
982 slave_config.direction = DMA_DEV_TO_MEM;
983 slave_config.src_addr = sport->port.mapbase + URXD0;
984 slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
985 slave_config.src_maxburst = RXTL;
986 ret = dmaengine_slave_config(sport->dma_chan_rx, &slave_config);
988 dev_err(dev, "error in RX dma configuration.\n");
992 sport->rx_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
993 if (!sport->rx_buf) {
994 dev_err(dev, "cannot alloc DMA buffer.\n");
999 /* Prepare for TX : */
1000 sport->dma_chan_tx = dma_request_slave_channel(dev, "tx");
1001 if (!sport->dma_chan_tx) {
1002 dev_err(dev, "cannot get the TX DMA channel!\n");
1007 slave_config.direction = DMA_MEM_TO_DEV;
1008 slave_config.dst_addr = sport->port.mapbase + URTX0;
1009 slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1010 slave_config.dst_maxburst = TXTL;
1011 ret = dmaengine_slave_config(sport->dma_chan_tx, &slave_config);
1013 dev_err(dev, "error in TX dma configuration.");
1017 sport->dma_is_inited = 1;
1021 imx_uart_dma_exit(sport);
1025 static void imx_enable_dma(struct imx_port *sport)
1029 init_waitqueue_head(&sport->dma_wait);
1032 temp = readl(sport->port.membase + UCR1);
1033 temp |= UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN |
1034 /* wait for 32 idle frames for IDDMA interrupt */
1036 writel(temp, sport->port.membase + UCR1);
1039 temp = readl(sport->port.membase + UCR4);
1040 temp |= UCR4_IDDMAEN;
1041 writel(temp, sport->port.membase + UCR4);
1043 sport->dma_is_enabled = 1;
1046 static void imx_disable_dma(struct imx_port *sport)
1051 temp = readl(sport->port.membase + UCR1);
1052 temp &= ~(UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN);
1053 writel(temp, sport->port.membase + UCR1);
1056 temp = readl(sport->port.membase + UCR2);
1057 temp &= ~(UCR2_CTSC | UCR2_CTS);
1058 writel(temp, sport->port.membase + UCR2);
1061 temp = readl(sport->port.membase + UCR4);
1062 temp &= ~UCR4_IDDMAEN;
1063 writel(temp, sport->port.membase + UCR4);
1065 sport->dma_is_enabled = 0;
1068 /* half the RX buffer size */
1071 static int imx_startup(struct uart_port *port)
1073 struct imx_port *sport = (struct imx_port *)port;
1075 unsigned long flags, temp;
1077 retval = clk_prepare_enable(sport->clk_per);
1080 retval = clk_prepare_enable(sport->clk_ipg);
1082 clk_disable_unprepare(sport->clk_per);
1086 imx_setup_ufcr(sport, 0);
1088 /* disable the DREN bit (Data Ready interrupt enable) before
1091 temp = readl(sport->port.membase + UCR4);
1093 if (USE_IRDA(sport))
1096 /* set the trigger level for CTS */
1097 temp &= ~(UCR4_CTSTL_MASK << UCR4_CTSTL_SHF);
1098 temp |= CTSTL << UCR4_CTSTL_SHF;
1100 writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
1102 /* Reset fifo's and state machines */
1105 temp = readl(sport->port.membase + UCR2);
1107 writel(temp, sport->port.membase + UCR2);
1109 while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) && (--i > 0))
1113 * Allocate the IRQ(s) i.MX1 has three interrupts whereas later
1114 * chips only have one interrupt.
1116 if (sport->txirq > 0) {
1117 retval = request_irq(sport->rxirq, imx_rxint, 0,
1118 dev_name(port->dev), sport);
1122 retval = request_irq(sport->txirq, imx_txint, 0,
1123 dev_name(port->dev), sport);
1127 /* do not use RTS IRQ on IrDA */
1128 if (!USE_IRDA(sport)) {
1129 retval = request_irq(sport->rtsirq, imx_rtsint, 0,
1130 dev_name(port->dev), sport);
1135 retval = request_irq(sport->port.irq, imx_int, 0,
1136 dev_name(port->dev), sport);
1138 free_irq(sport->port.irq, sport);
1143 spin_lock_irqsave(&sport->port.lock, flags);
1145 * Finally, clear and enable interrupts
1147 writel(USR1_RTSD, sport->port.membase + USR1);
1149 temp = readl(sport->port.membase + UCR1);
1150 temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
1152 if (USE_IRDA(sport)) {
1154 temp &= ~(UCR1_RTSDEN);
1157 writel(temp, sport->port.membase + UCR1);
1159 temp = readl(sport->port.membase + UCR2);
1160 temp |= (UCR2_RXEN | UCR2_TXEN);
1161 if (!sport->have_rtscts)
1163 writel(temp, sport->port.membase + UCR2);
1165 if (!is_imx1_uart(sport)) {
1166 temp = readl(sport->port.membase + UCR3);
1167 temp |= IMX21_UCR3_RXDMUXSEL | UCR3_ADNIMP;
1168 writel(temp, sport->port.membase + UCR3);
1171 if (USE_IRDA(sport)) {
1172 temp = readl(sport->port.membase + UCR4);
1173 if (sport->irda_inv_rx)
1176 temp &= ~(UCR4_INVR);
1177 writel(temp | UCR4_DREN, sport->port.membase + UCR4);
1179 temp = readl(sport->port.membase + UCR3);
1180 if (sport->irda_inv_tx)
1183 temp &= ~(UCR3_INVT);
1184 writel(temp, sport->port.membase + UCR3);
1188 * Enable modem status interrupts
1190 imx_enable_ms(&sport->port);
1191 spin_unlock_irqrestore(&sport->port.lock, flags);
1193 if (USE_IRDA(sport)) {
1194 struct imxuart_platform_data *pdata;
1195 pdata = dev_get_platdata(sport->port.dev);
1196 sport->irda_inv_rx = pdata->irda_inv_rx;
1197 sport->irda_inv_tx = pdata->irda_inv_tx;
1198 sport->trcv_delay = pdata->transceiver_delay;
1199 if (pdata->irda_enable)
1200 pdata->irda_enable(1);
1207 free_irq(sport->txirq, sport);
1210 free_irq(sport->rxirq, sport);
1215 static void imx_shutdown(struct uart_port *port)
1217 struct imx_port *sport = (struct imx_port *)port;
1219 unsigned long flags;
1221 if (sport->dma_is_enabled) {
1224 /* We have to wait for the DMA to finish. */
1225 ret = wait_event_interruptible(sport->dma_wait,
1226 !sport->dma_is_rxing && !sport->dma_is_txing);
1228 sport->dma_is_rxing = 0;
1229 sport->dma_is_txing = 0;
1230 dmaengine_terminate_all(sport->dma_chan_tx);
1231 dmaengine_terminate_all(sport->dma_chan_rx);
1235 imx_disable_dma(sport);
1236 imx_uart_dma_exit(sport);
1239 spin_lock_irqsave(&sport->port.lock, flags);
1240 temp = readl(sport->port.membase + UCR2);
1241 temp &= ~(UCR2_TXEN);
1242 writel(temp, sport->port.membase + UCR2);
1243 spin_unlock_irqrestore(&sport->port.lock, flags);
1245 if (USE_IRDA(sport)) {
1246 struct imxuart_platform_data *pdata;
1247 pdata = dev_get_platdata(sport->port.dev);
1248 if (pdata->irda_enable)
1249 pdata->irda_enable(0);
1255 del_timer_sync(&sport->timer);
1258 * Free the interrupts
1260 if (sport->txirq > 0) {
1261 if (!USE_IRDA(sport))
1262 free_irq(sport->rtsirq, sport);
1263 free_irq(sport->txirq, sport);
1264 free_irq(sport->rxirq, sport);
1266 free_irq(sport->port.irq, sport);
1269 * Disable all interrupts, port and break condition.
1272 spin_lock_irqsave(&sport->port.lock, flags);
1273 temp = readl(sport->port.membase + UCR1);
1274 temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN);
1275 if (USE_IRDA(sport))
1276 temp &= ~(UCR1_IREN);
1278 writel(temp, sport->port.membase + UCR1);
1279 spin_unlock_irqrestore(&sport->port.lock, flags);
1281 clk_disable_unprepare(sport->clk_per);
1282 clk_disable_unprepare(sport->clk_ipg);
1285 static void imx_flush_buffer(struct uart_port *port)
1287 struct imx_port *sport = (struct imx_port *)port;
1289 if (sport->dma_is_enabled) {
1290 sport->tx_bytes = 0;
1291 dmaengine_terminate_all(sport->dma_chan_tx);
1296 imx_set_termios(struct uart_port *port, struct ktermios *termios,
1297 struct ktermios *old)
1299 struct imx_port *sport = (struct imx_port *)port;
1300 unsigned long flags;
1301 unsigned int ucr2, old_ucr1, old_txrxen, baud, quot;
1302 unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1303 unsigned int div, ufcr;
1304 unsigned long num, denom;
1308 * If we don't support modem control lines, don't allow
1312 termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR);
1313 termios->c_cflag |= CLOCAL;
1317 * We only support CS7 and CS8.
1319 while ((termios->c_cflag & CSIZE) != CS7 &&
1320 (termios->c_cflag & CSIZE) != CS8) {
1321 termios->c_cflag &= ~CSIZE;
1322 termios->c_cflag |= old_csize;
1326 if ((termios->c_cflag & CSIZE) == CS8)
1327 ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS;
1329 ucr2 = UCR2_SRST | UCR2_IRTS;
1331 if (termios->c_cflag & CRTSCTS) {
1332 if (sport->have_rtscts) {
1336 /* Can we enable the DMA support? */
1337 if (is_imx6q_uart(sport) && !uart_console(port)
1338 && !sport->dma_is_inited)
1339 imx_uart_dma_init(sport);
1341 termios->c_cflag &= ~CRTSCTS;
1345 if (termios->c_cflag & CSTOPB)
1347 if (termios->c_cflag & PARENB) {
1349 if (termios->c_cflag & PARODD)
1353 del_timer_sync(&sport->timer);
1356 * Ask the core to calculate the divisor for us.
1358 baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
1359 quot = uart_get_divisor(port, baud);
1361 spin_lock_irqsave(&sport->port.lock, flags);
1363 sport->port.read_status_mask = 0;
1364 if (termios->c_iflag & INPCK)
1365 sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR);
1366 if (termios->c_iflag & (BRKINT | PARMRK))
1367 sport->port.read_status_mask |= URXD_BRK;
1370 * Characters to ignore
1372 sport->port.ignore_status_mask = 0;
1373 if (termios->c_iflag & IGNPAR)
1374 sport->port.ignore_status_mask |= URXD_PRERR;
1375 if (termios->c_iflag & IGNBRK) {
1376 sport->port.ignore_status_mask |= URXD_BRK;
1378 * If we're ignoring parity and break indicators,
1379 * ignore overruns too (for real raw support).
1381 if (termios->c_iflag & IGNPAR)
1382 sport->port.ignore_status_mask |= URXD_OVRRUN;
1386 * Update the per-port timeout.
1388 uart_update_timeout(port, termios->c_cflag, baud);
1391 * disable interrupts and drain transmitter
1393 old_ucr1 = readl(sport->port.membase + UCR1);
1394 writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN),
1395 sport->port.membase + UCR1);
1397 while (!(readl(sport->port.membase + USR2) & USR2_TXDC))
1400 /* then, disable everything */
1401 old_txrxen = readl(sport->port.membase + UCR2);
1402 writel(old_txrxen & ~(UCR2_TXEN | UCR2_RXEN),
1403 sport->port.membase + UCR2);
1404 old_txrxen &= (UCR2_TXEN | UCR2_RXEN);
1406 if (USE_IRDA(sport)) {
1408 * use maximum available submodule frequency to
1409 * avoid missing short pulses due to low sampling rate
1413 /* custom-baudrate handling */
1414 div = sport->port.uartclk / (baud * 16);
1415 if (baud == 38400 && quot != div)
1416 baud = sport->port.uartclk / (quot * 16);
1418 div = sport->port.uartclk / (baud * 16);
1425 rational_best_approximation(16 * div * baud, sport->port.uartclk,
1426 1 << 16, 1 << 16, &num, &denom);
1428 tdiv64 = sport->port.uartclk;
1430 do_div(tdiv64, denom * 16 * div);
1431 tty_termios_encode_baud_rate(termios,
1432 (speed_t)tdiv64, (speed_t)tdiv64);
1437 ufcr = readl(sport->port.membase + UFCR);
1438 ufcr = (ufcr & (~UFCR_RFDIV)) | UFCR_RFDIV_REG(div);
1439 if (sport->dte_mode)
1440 ufcr |= UFCR_DCEDTE;
1441 writel(ufcr, sport->port.membase + UFCR);
1443 writel(num, sport->port.membase + UBIR);
1444 writel(denom, sport->port.membase + UBMR);
1446 if (!is_imx1_uart(sport))
1447 writel(sport->port.uartclk / div / 1000,
1448 sport->port.membase + IMX21_ONEMS);
1450 writel(old_ucr1, sport->port.membase + UCR1);
1452 /* set the parity, stop bits and data size */
1453 writel(ucr2 | old_txrxen, sport->port.membase + UCR2);
1455 if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
1456 imx_enable_ms(&sport->port);
1458 if (sport->dma_is_inited && !sport->dma_is_enabled)
1459 imx_enable_dma(sport);
1460 spin_unlock_irqrestore(&sport->port.lock, flags);
1463 static const char *imx_type(struct uart_port *port)
1465 struct imx_port *sport = (struct imx_port *)port;
1467 return sport->port.type == PORT_IMX ? "IMX" : NULL;
1471 * Configure/autoconfigure the port.
1473 static void imx_config_port(struct uart_port *port, int flags)
1475 struct imx_port *sport = (struct imx_port *)port;
1477 if (flags & UART_CONFIG_TYPE)
1478 sport->port.type = PORT_IMX;
1482 * Verify the new serial_struct (for TIOCSSERIAL).
1483 * The only change we allow are to the flags and type, and
1484 * even then only between PORT_IMX and PORT_UNKNOWN
1487 imx_verify_port(struct uart_port *port, struct serial_struct *ser)
1489 struct imx_port *sport = (struct imx_port *)port;
1492 if (ser->type != PORT_UNKNOWN && ser->type != PORT_IMX)
1494 if (sport->port.irq != ser->irq)
1496 if (ser->io_type != UPIO_MEM)
1498 if (sport->port.uartclk / 16 != ser->baud_base)
1500 if (sport->port.mapbase != (unsigned long)ser->iomem_base)
1502 if (sport->port.iobase != ser->port)
1509 #if defined(CONFIG_CONSOLE_POLL)
1510 static int imx_poll_get_char(struct uart_port *port)
1512 if (!(readl(port->membase + USR2) & USR2_RDR))
1513 return NO_POLL_CHAR;
1515 return readl(port->membase + URXD0) & URXD_RX_DATA;
1518 static void imx_poll_put_char(struct uart_port *port, unsigned char c)
1520 struct imx_port_ucrs old_ucr;
1521 unsigned int status;
1523 /* save control registers */
1524 imx_port_ucrs_save(port, &old_ucr);
1526 /* disable interrupts */
1527 writel(UCR1_UARTEN, port->membase + UCR1);
1528 writel(old_ucr.ucr2 & ~(UCR2_ATEN | UCR2_RTSEN | UCR2_ESCI),
1529 port->membase + UCR2);
1530 writel(old_ucr.ucr3 & ~(UCR3_DCD | UCR3_RI | UCR3_DTREN),
1531 port->membase + UCR3);
1535 status = readl(port->membase + USR1);
1536 } while (~status & USR1_TRDY);
1539 writel(c, port->membase + URTX0);
1543 status = readl(port->membase + USR2);
1544 } while (~status & USR2_TXDC);
1546 /* restore control registers */
1547 imx_port_ucrs_restore(port, &old_ucr);
1551 static struct uart_ops imx_pops = {
1552 .tx_empty = imx_tx_empty,
1553 .set_mctrl = imx_set_mctrl,
1554 .get_mctrl = imx_get_mctrl,
1555 .stop_tx = imx_stop_tx,
1556 .start_tx = imx_start_tx,
1557 .stop_rx = imx_stop_rx,
1558 .enable_ms = imx_enable_ms,
1559 .break_ctl = imx_break_ctl,
1560 .startup = imx_startup,
1561 .shutdown = imx_shutdown,
1562 .flush_buffer = imx_flush_buffer,
1563 .set_termios = imx_set_termios,
1565 .config_port = imx_config_port,
1566 .verify_port = imx_verify_port,
1567 #if defined(CONFIG_CONSOLE_POLL)
1568 .poll_get_char = imx_poll_get_char,
1569 .poll_put_char = imx_poll_put_char,
1573 static struct imx_port *imx_ports[UART_NR];
1575 #ifdef CONFIG_SERIAL_IMX_CONSOLE
1576 static void imx_console_putchar(struct uart_port *port, int ch)
1578 struct imx_port *sport = (struct imx_port *)port;
1580 while (readl(sport->port.membase + uts_reg(sport)) & UTS_TXFULL)
1583 writel(ch, sport->port.membase + URTX0);
1587 * Interrupts are disabled on entering
1590 imx_console_write(struct console *co, const char *s, unsigned int count)
1592 struct imx_port *sport = imx_ports[co->index];
1593 struct imx_port_ucrs old_ucr;
1595 unsigned long flags = 0;
1599 retval = clk_enable(sport->clk_per);
1602 retval = clk_enable(sport->clk_ipg);
1604 clk_disable(sport->clk_per);
1608 if (sport->port.sysrq)
1610 else if (oops_in_progress)
1611 locked = spin_trylock_irqsave(&sport->port.lock, flags);
1613 spin_lock_irqsave(&sport->port.lock, flags);
1616 * First, save UCR1/2/3 and then disable interrupts
1618 imx_port_ucrs_save(&sport->port, &old_ucr);
1619 ucr1 = old_ucr.ucr1;
1621 if (is_imx1_uart(sport))
1622 ucr1 |= IMX1_UCR1_UARTCLKEN;
1623 ucr1 |= UCR1_UARTEN;
1624 ucr1 &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN);
1626 writel(ucr1, sport->port.membase + UCR1);
1628 writel(old_ucr.ucr2 | UCR2_TXEN, sport->port.membase + UCR2);
1630 uart_console_write(&sport->port, s, count, imx_console_putchar);
1633 * Finally, wait for transmitter to become empty
1634 * and restore UCR1/2/3
1636 while (!(readl(sport->port.membase + USR2) & USR2_TXDC));
1638 imx_port_ucrs_restore(&sport->port, &old_ucr);
1641 spin_unlock_irqrestore(&sport->port.lock, flags);
1643 clk_disable(sport->clk_ipg);
1644 clk_disable(sport->clk_per);
1648 * If the port was already initialised (eg, by a boot loader),
1649 * try to determine the current setup.
1652 imx_console_get_options(struct imx_port *sport, int *baud,
1653 int *parity, int *bits)
1656 if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) {
1657 /* ok, the port was enabled */
1658 unsigned int ucr2, ubir, ubmr, uartclk;
1659 unsigned int baud_raw;
1660 unsigned int ucfr_rfdiv;
1662 ucr2 = readl(sport->port.membase + UCR2);
1665 if (ucr2 & UCR2_PREN) {
1666 if (ucr2 & UCR2_PROE)
1677 ubir = readl(sport->port.membase + UBIR) & 0xffff;
1678 ubmr = readl(sport->port.membase + UBMR) & 0xffff;
1680 ucfr_rfdiv = (readl(sport->port.membase + UFCR) & UFCR_RFDIV) >> 7;
1681 if (ucfr_rfdiv == 6)
1684 ucfr_rfdiv = 6 - ucfr_rfdiv;
1686 uartclk = clk_get_rate(sport->clk_per);
1687 uartclk /= ucfr_rfdiv;
1690 * The next code provides exact computation of
1691 * baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
1692 * without need of float support or long long division,
1693 * which would be required to prevent 32bit arithmetic overflow
1695 unsigned int mul = ubir + 1;
1696 unsigned int div = 16 * (ubmr + 1);
1697 unsigned int rem = uartclk % div;
1699 baud_raw = (uartclk / div) * mul;
1700 baud_raw += (rem * mul + div / 2) / div;
1701 *baud = (baud_raw + 50) / 100 * 100;
1704 if (*baud != baud_raw)
1705 pr_info("Console IMX rounded baud rate from %d to %d\n",
1711 imx_console_setup(struct console *co, char *options)
1713 struct imx_port *sport;
1721 * Check whether an invalid uart number has been specified, and
1722 * if so, search for the first available port that does have
1725 if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports))
1727 sport = imx_ports[co->index];
1731 /* For setting the registers, we only need to enable the ipg clock. */
1732 retval = clk_prepare_enable(sport->clk_ipg);
1737 uart_parse_options(options, &baud, &parity, &bits, &flow);
1739 imx_console_get_options(sport, &baud, &parity, &bits);
1741 imx_setup_ufcr(sport, 0);
1743 retval = uart_set_options(&sport->port, co, baud, parity, bits, flow);
1745 clk_disable(sport->clk_ipg);
1747 clk_unprepare(sport->clk_ipg);
1751 retval = clk_prepare(sport->clk_per);
1753 clk_disable_unprepare(sport->clk_ipg);
1759 static struct uart_driver imx_reg;
1760 static struct console imx_console = {
1762 .write = imx_console_write,
1763 .device = uart_console_device,
1764 .setup = imx_console_setup,
1765 .flags = CON_PRINTBUFFER,
1770 #define IMX_CONSOLE &imx_console
1772 #define IMX_CONSOLE NULL
1775 static struct uart_driver imx_reg = {
1776 .owner = THIS_MODULE,
1777 .driver_name = DRIVER_NAME,
1778 .dev_name = DEV_NAME,
1779 .major = SERIAL_IMX_MAJOR,
1780 .minor = MINOR_START,
1781 .nr = ARRAY_SIZE(imx_ports),
1782 .cons = IMX_CONSOLE,
1785 static int serial_imx_suspend(struct platform_device *dev, pm_message_t state)
1787 struct imx_port *sport = platform_get_drvdata(dev);
1790 /* enable wakeup from i.MX UART */
1791 val = readl(sport->port.membase + UCR3);
1793 writel(val, sport->port.membase + UCR3);
1795 uart_suspend_port(&imx_reg, &sport->port);
1800 static int serial_imx_resume(struct platform_device *dev)
1802 struct imx_port *sport = platform_get_drvdata(dev);
1805 /* disable wakeup from i.MX UART */
1806 val = readl(sport->port.membase + UCR3);
1807 val &= ~UCR3_AWAKEN;
1808 writel(val, sport->port.membase + UCR3);
1810 uart_resume_port(&imx_reg, &sport->port);
1817 * This function returns 1 iff pdev isn't a device instatiated by dt, 0 iff it
1818 * could successfully get all information from dt or a negative errno.
1820 static int serial_imx_probe_dt(struct imx_port *sport,
1821 struct platform_device *pdev)
1823 struct device_node *np = pdev->dev.of_node;
1824 const struct of_device_id *of_id =
1825 of_match_device(imx_uart_dt_ids, &pdev->dev);
1829 /* no device tree device */
1832 ret = of_alias_get_id(np, "serial");
1834 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
1837 sport->port.line = ret;
1839 if (of_get_property(np, "fsl,uart-has-rtscts", NULL))
1840 sport->have_rtscts = 1;
1842 if (of_get_property(np, "fsl,irda-mode", NULL))
1843 sport->use_irda = 1;
1845 if (of_get_property(np, "fsl,dte-mode", NULL))
1846 sport->dte_mode = 1;
1848 sport->devdata = of_id->data;
1853 static inline int serial_imx_probe_dt(struct imx_port *sport,
1854 struct platform_device *pdev)
1860 static void serial_imx_probe_pdata(struct imx_port *sport,
1861 struct platform_device *pdev)
1863 struct imxuart_platform_data *pdata = dev_get_platdata(&pdev->dev);
1865 sport->port.line = pdev->id;
1866 sport->devdata = (struct imx_uart_data *) pdev->id_entry->driver_data;
1871 if (pdata->flags & IMXUART_HAVE_RTSCTS)
1872 sport->have_rtscts = 1;
1874 if (pdata->flags & IMXUART_IRDA)
1875 sport->use_irda = 1;
1878 static int serial_imx_probe(struct platform_device *pdev)
1880 struct imx_port *sport;
1883 struct resource *res;
1885 sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
1889 ret = serial_imx_probe_dt(sport, pdev);
1891 serial_imx_probe_pdata(sport, pdev);
1895 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1896 base = devm_ioremap_resource(&pdev->dev, res);
1898 return PTR_ERR(base);
1900 sport->port.dev = &pdev->dev;
1901 sport->port.mapbase = res->start;
1902 sport->port.membase = base;
1903 sport->port.type = PORT_IMX,
1904 sport->port.iotype = UPIO_MEM;
1905 sport->port.irq = platform_get_irq(pdev, 0);
1906 sport->rxirq = platform_get_irq(pdev, 0);
1907 sport->txirq = platform_get_irq(pdev, 1);
1908 sport->rtsirq = platform_get_irq(pdev, 2);
1909 sport->port.fifosize = 32;
1910 sport->port.ops = &imx_pops;
1911 sport->port.flags = UPF_BOOT_AUTOCONF;
1912 init_timer(&sport->timer);
1913 sport->timer.function = imx_timeout;
1914 sport->timer.data = (unsigned long)sport;
1916 sport->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1917 if (IS_ERR(sport->clk_ipg)) {
1918 ret = PTR_ERR(sport->clk_ipg);
1919 dev_err(&pdev->dev, "failed to get ipg clk: %d\n", ret);
1923 sport->clk_per = devm_clk_get(&pdev->dev, "per");
1924 if (IS_ERR(sport->clk_per)) {
1925 ret = PTR_ERR(sport->clk_per);
1926 dev_err(&pdev->dev, "failed to get per clk: %d\n", ret);
1930 sport->port.uartclk = clk_get_rate(sport->clk_per);
1932 imx_ports[sport->port.line] = sport;
1934 platform_set_drvdata(pdev, sport);
1936 return uart_add_one_port(&imx_reg, &sport->port);
1939 static int serial_imx_remove(struct platform_device *pdev)
1941 struct imx_port *sport = platform_get_drvdata(pdev);
1943 return uart_remove_one_port(&imx_reg, &sport->port);
1946 static struct platform_driver serial_imx_driver = {
1947 .probe = serial_imx_probe,
1948 .remove = serial_imx_remove,
1950 .suspend = serial_imx_suspend,
1951 .resume = serial_imx_resume,
1952 .id_table = imx_uart_devtype,
1955 .owner = THIS_MODULE,
1956 .of_match_table = imx_uart_dt_ids,
1960 static int __init imx_serial_init(void)
1964 pr_info("Serial: IMX driver\n");
1966 ret = uart_register_driver(&imx_reg);
1970 ret = platform_driver_register(&serial_imx_driver);
1972 uart_unregister_driver(&imx_reg);
1977 static void __exit imx_serial_exit(void)
1979 platform_driver_unregister(&serial_imx_driver);
1980 uart_unregister_driver(&imx_reg);
1983 module_init(imx_serial_init);
1984 module_exit(imx_serial_exit);
1986 MODULE_AUTHOR("Sascha Hauer");
1987 MODULE_DESCRIPTION("IMX generic serial port driver");
1988 MODULE_LICENSE("GPL");
1989 MODULE_ALIAS("platform:imx-uart");