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_DUMMY_READ (1<<16)
78 #define URXD_CHARRDY (1<<15)
79 #define URXD_ERR (1<<14)
80 #define URXD_OVRRUN (1<<13)
81 #define URXD_FRMERR (1<<12)
82 #define URXD_BRK (1<<11)
83 #define URXD_PRERR (1<<10)
84 #define URXD_RX_DATA (0xFF<<0)
85 #define UCR1_ADEN (1<<15) /* Auto detect interrupt */
86 #define UCR1_ADBR (1<<14) /* Auto detect baud rate */
87 #define UCR1_TRDYEN (1<<13) /* Transmitter ready interrupt enable */
88 #define UCR1_IDEN (1<<12) /* Idle condition interrupt */
89 #define UCR1_ICD_REG(x) (((x) & 3) << 10) /* idle condition detect */
90 #define UCR1_RRDYEN (1<<9) /* Recv ready interrupt enable */
91 #define UCR1_RDMAEN (1<<8) /* Recv ready DMA enable */
92 #define UCR1_IREN (1<<7) /* Infrared interface enable */
93 #define UCR1_TXMPTYEN (1<<6) /* Transimitter empty interrupt enable */
94 #define UCR1_RTSDEN (1<<5) /* RTS delta interrupt enable */
95 #define UCR1_SNDBRK (1<<4) /* Send break */
96 #define UCR1_TDMAEN (1<<3) /* Transmitter ready DMA enable */
97 #define IMX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, i.mx1 only */
98 #define UCR1_ATDMAEN (1<<2) /* Aging DMA Timer Enable */
99 #define UCR1_DOZE (1<<1) /* Doze */
100 #define UCR1_UARTEN (1<<0) /* UART enabled */
101 #define UCR2_ESCI (1<<15) /* Escape seq interrupt enable */
102 #define UCR2_IRTS (1<<14) /* Ignore RTS pin */
103 #define UCR2_CTSC (1<<13) /* CTS pin control */
104 #define UCR2_CTS (1<<12) /* Clear to send */
105 #define UCR2_ESCEN (1<<11) /* Escape enable */
106 #define UCR2_PREN (1<<8) /* Parity enable */
107 #define UCR2_PROE (1<<7) /* Parity odd/even */
108 #define UCR2_STPB (1<<6) /* Stop */
109 #define UCR2_WS (1<<5) /* Word size */
110 #define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */
111 #define UCR2_ATEN (1<<3) /* Aging Timer Enable */
112 #define UCR2_TXEN (1<<2) /* Transmitter enabled */
113 #define UCR2_RXEN (1<<1) /* Receiver enabled */
114 #define UCR2_SRST (1<<0) /* SW reset */
115 #define UCR3_DTREN (1<<13) /* DTR interrupt enable */
116 #define UCR3_PARERREN (1<<12) /* Parity enable */
117 #define UCR3_FRAERREN (1<<11) /* Frame error interrupt enable */
118 #define UCR3_DSR (1<<10) /* Data set ready */
119 #define UCR3_DCD (1<<9) /* Data carrier detect */
120 #define UCR3_RI (1<<8) /* Ring indicator */
121 #define UCR3_ADNIMP (1<<7) /* Autobaud Detection Not Improved */
122 #define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */
123 #define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */
124 #define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */
125 #define IMX21_UCR3_RXDMUXSEL (1<<2) /* RXD Muxed Input Select */
126 #define UCR3_INVT (1<<1) /* Inverted Infrared transmission */
127 #define UCR3_BPEN (1<<0) /* Preset registers enable */
128 #define UCR4_CTSTL_SHF 10 /* CTS trigger level shift */
129 #define UCR4_CTSTL_MASK 0x3F /* CTS trigger is 6 bits wide */
130 #define UCR4_INVR (1<<9) /* Inverted infrared reception */
131 #define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */
132 #define UCR4_WKEN (1<<7) /* Wake interrupt enable */
133 #define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */
134 #define UCR4_IDDMAEN (1<<6) /* DMA IDLE Condition Detected */
135 #define UCR4_IRSC (1<<5) /* IR special case */
136 #define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */
137 #define UCR4_BKEN (1<<2) /* Break condition interrupt enable */
138 #define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */
139 #define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */
140 #define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */
141 #define UFCR_DCEDTE (1<<6) /* DCE/DTE mode select */
142 #define UFCR_RFDIV (7<<7) /* Reference freq divider mask */
143 #define UFCR_RFDIV_REG(x) (((x) < 7 ? 6 - (x) : 6) << 7)
144 #define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */
145 #define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */
146 #define USR1_RTSS (1<<14) /* RTS pin status */
147 #define USR1_TRDY (1<<13) /* Transmitter ready interrupt/dma flag */
148 #define USR1_RTSD (1<<12) /* RTS delta */
149 #define USR1_ESCF (1<<11) /* Escape seq interrupt flag */
150 #define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */
151 #define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */
152 #define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */
153 #define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */
154 #define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */
155 #define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */
156 #define USR2_ADET (1<<15) /* Auto baud rate detect complete */
157 #define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */
158 #define USR2_DTRF (1<<13) /* DTR edge interrupt flag */
159 #define USR2_IDLE (1<<12) /* Idle condition */
160 #define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */
161 #define USR2_WAKE (1<<7) /* Wake */
162 #define USR2_RTSF (1<<4) /* RTS edge interrupt flag */
163 #define USR2_TXDC (1<<3) /* Transmitter complete */
164 #define USR2_BRCD (1<<2) /* Break condition */
165 #define USR2_ORE (1<<1) /* Overrun error */
166 #define USR2_RDR (1<<0) /* Recv data ready */
167 #define UTS_FRCPERR (1<<13) /* Force parity error */
168 #define UTS_LOOP (1<<12) /* Loop tx and rx */
169 #define UTS_TXEMPTY (1<<6) /* TxFIFO empty */
170 #define UTS_RXEMPTY (1<<5) /* RxFIFO empty */
171 #define UTS_TXFULL (1<<4) /* TxFIFO full */
172 #define UTS_RXFULL (1<<3) /* RxFIFO full */
173 #define UTS_SOFTRST (1<<0) /* Software reset */
175 /* We've been assigned a range on the "Low-density serial ports" major */
176 #define SERIAL_IMX_MAJOR 207
177 #define MINOR_START 16
178 #define DEV_NAME "ttymxc"
181 * This determines how often we check the modem status signals
182 * for any change. They generally aren't connected to an IRQ
183 * so we have to poll them. We also check immediately before
184 * filling the TX fifo incase CTS has been dropped.
186 #define MCTRL_TIMEOUT (250*HZ/1000)
188 #define DRIVER_NAME "IMX-uart"
192 /* i.mx21 type uart runs on all i.mx except i.mx1 */
199 /* device type dependent stuff */
200 struct imx_uart_data {
202 enum imx_uart_type devtype;
206 struct uart_port port;
207 struct timer_list timer;
208 unsigned int old_status;
209 int txirq, rxirq, rtsirq;
210 unsigned int have_rtscts:1;
211 unsigned int dte_mode:1;
212 unsigned int use_irda:1;
213 unsigned int irda_inv_rx:1;
214 unsigned int irda_inv_tx:1;
215 unsigned short trcv_delay; /* transceiver delay */
218 const struct imx_uart_data *devdata;
221 unsigned int dma_is_inited:1;
222 unsigned int dma_is_enabled:1;
223 unsigned int dma_is_rxing:1;
224 unsigned int dma_is_txing:1;
225 struct dma_chan *dma_chan_rx, *dma_chan_tx;
226 struct scatterlist rx_sgl, tx_sgl[2];
228 unsigned int tx_bytes;
229 unsigned int dma_tx_nents;
230 wait_queue_head_t dma_wait;
233 struct imx_port_ucrs {
240 #define USE_IRDA(sport) ((sport)->use_irda)
242 #define USE_IRDA(sport) (0)
245 static struct imx_uart_data imx_uart_devdata[] = {
248 .devtype = IMX1_UART,
251 .uts_reg = IMX21_UTS,
252 .devtype = IMX21_UART,
255 .uts_reg = IMX21_UTS,
256 .devtype = IMX6Q_UART,
260 static struct platform_device_id imx_uart_devtype[] = {
263 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX1_UART],
265 .name = "imx21-uart",
266 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX21_UART],
268 .name = "imx6q-uart",
269 .driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX6Q_UART],
274 MODULE_DEVICE_TABLE(platform, imx_uart_devtype);
276 static struct of_device_id imx_uart_dt_ids[] = {
277 { .compatible = "fsl,imx6q-uart", .data = &imx_uart_devdata[IMX6Q_UART], },
278 { .compatible = "fsl,imx1-uart", .data = &imx_uart_devdata[IMX1_UART], },
279 { .compatible = "fsl,imx21-uart", .data = &imx_uart_devdata[IMX21_UART], },
282 MODULE_DEVICE_TABLE(of, imx_uart_dt_ids);
284 static inline unsigned uts_reg(struct imx_port *sport)
286 return sport->devdata->uts_reg;
289 static inline int is_imx1_uart(struct imx_port *sport)
291 return sport->devdata->devtype == IMX1_UART;
294 static inline int is_imx21_uart(struct imx_port *sport)
296 return sport->devdata->devtype == IMX21_UART;
299 static inline int is_imx6q_uart(struct imx_port *sport)
301 return sport->devdata->devtype == IMX6Q_UART;
304 * Save and restore functions for UCR1, UCR2 and UCR3 registers
306 #if defined(CONFIG_SERIAL_IMX_CONSOLE)
307 static void imx_port_ucrs_save(struct uart_port *port,
308 struct imx_port_ucrs *ucr)
310 /* save control registers */
311 ucr->ucr1 = readl(port->membase + UCR1);
312 ucr->ucr2 = readl(port->membase + UCR2);
313 ucr->ucr3 = readl(port->membase + UCR3);
316 static void imx_port_ucrs_restore(struct uart_port *port,
317 struct imx_port_ucrs *ucr)
319 /* restore control registers */
320 writel(ucr->ucr1, port->membase + UCR1);
321 writel(ucr->ucr2, port->membase + UCR2);
322 writel(ucr->ucr3, port->membase + UCR3);
327 * Handle any change of modem status signal since we were last called.
329 static void imx_mctrl_check(struct imx_port *sport)
331 unsigned int status, changed;
333 status = sport->port.ops->get_mctrl(&sport->port);
334 changed = status ^ sport->old_status;
339 sport->old_status = status;
341 if (changed & TIOCM_RI)
342 sport->port.icount.rng++;
343 if (changed & TIOCM_DSR)
344 sport->port.icount.dsr++;
345 if (changed & TIOCM_CAR)
346 uart_handle_dcd_change(&sport->port, status & TIOCM_CAR);
347 if (changed & TIOCM_CTS)
348 uart_handle_cts_change(&sport->port, status & TIOCM_CTS);
350 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
354 * This is our per-port timeout handler, for checking the
355 * modem status signals.
357 static void imx_timeout(unsigned long data)
359 struct imx_port *sport = (struct imx_port *)data;
362 if (sport->port.state) {
363 spin_lock_irqsave(&sport->port.lock, flags);
364 imx_mctrl_check(sport);
365 spin_unlock_irqrestore(&sport->port.lock, flags);
367 mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT);
372 * interrupts disabled on entry
374 static void imx_stop_tx(struct uart_port *port)
376 struct imx_port *sport = (struct imx_port *)port;
379 if (USE_IRDA(sport)) {
380 /* half duplex - wait for end of transmission */
383 !(readl(sport->port.membase + USR2) & USR2_TXDC)) {
388 * irda transceiver - wait a bit more to avoid
389 * cutoff, hardware dependent
391 udelay(sport->trcv_delay);
394 * half duplex - reactivate receive mode,
395 * flush receive pipe echo crap
397 if (readl(sport->port.membase + USR2) & USR2_TXDC) {
398 temp = readl(sport->port.membase + UCR1);
399 temp &= ~(UCR1_TXMPTYEN | UCR1_TRDYEN);
400 writel(temp, sport->port.membase + UCR1);
402 temp = readl(sport->port.membase + UCR4);
403 temp &= ~(UCR4_TCEN);
404 writel(temp, sport->port.membase + UCR4);
406 while (readl(sport->port.membase + URXD0) &
410 temp = readl(sport->port.membase + UCR1);
412 writel(temp, sport->port.membase + UCR1);
414 temp = readl(sport->port.membase + UCR4);
416 writel(temp, sport->port.membase + UCR4);
422 * We are maybe in the SMP context, so if the DMA TX thread is running
423 * on other cpu, we have to wait for it to finish.
425 if (sport->dma_is_enabled && sport->dma_is_txing)
428 temp = readl(sport->port.membase + UCR1);
429 writel(temp & ~UCR1_TXMPTYEN, sport->port.membase + UCR1);
433 * interrupts disabled on entry
435 static void imx_stop_rx(struct uart_port *port)
437 struct imx_port *sport = (struct imx_port *)port;
440 if (sport->dma_is_enabled && sport->dma_is_rxing) {
441 if (sport->port.suspended) {
442 dmaengine_terminate_all(sport->dma_chan_rx);
443 sport->dma_is_rxing = 0;
449 temp = readl(sport->port.membase + UCR2);
450 writel(temp & ~UCR2_RXEN, sport->port.membase + UCR2);
452 /* disable the `Receiver Ready Interrrupt` */
453 temp = readl(sport->port.membase + UCR1);
454 writel(temp & ~UCR1_RRDYEN, sport->port.membase + UCR1);
458 * Set the modem control timer to fire immediately.
460 static void imx_enable_ms(struct uart_port *port)
462 struct imx_port *sport = (struct imx_port *)port;
464 mod_timer(&sport->timer, jiffies);
467 static inline void imx_transmit_buffer(struct imx_port *sport)
469 struct circ_buf *xmit = &sport->port.state->xmit;
471 if (sport->port.x_char) {
473 writel(sport->port.x_char, sport->port.membase + URTX0);
474 sport->port.icount.tx++;
475 sport->port.x_char = 0;
479 if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
480 imx_stop_tx(&sport->port);
484 while (!uart_circ_empty(xmit) &&
485 !(readl(sport->port.membase + uts_reg(sport)) & UTS_TXFULL)) {
486 /* send xmit->buf[xmit->tail]
487 * out the port here */
488 writel(xmit->buf[xmit->tail], sport->port.membase + URTX0);
489 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
490 sport->port.icount.tx++;
493 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
494 uart_write_wakeup(&sport->port);
496 if (uart_circ_empty(xmit))
497 imx_stop_tx(&sport->port);
500 static void imx_dma_tx(struct imx_port *sport);
501 static void dma_tx_callback(void *data)
503 struct imx_port *sport = data;
504 struct scatterlist *sgl = &sport->tx_sgl[0];
505 struct circ_buf *xmit = &sport->port.state->xmit;
509 spin_lock_irqsave(&sport->port.lock, flags);
511 dma_unmap_sg(sport->port.dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
513 temp = readl(sport->port.membase + UCR1);
514 temp &= ~UCR1_TDMAEN;
515 writel(temp, sport->port.membase + UCR1);
517 /* update the stat */
518 xmit->tail = (xmit->tail + sport->tx_bytes) & (UART_XMIT_SIZE - 1);
519 sport->port.icount.tx += sport->tx_bytes;
521 dev_dbg(sport->port.dev, "we finish the TX DMA.\n");
523 sport->dma_is_txing = 0;
525 spin_unlock_irqrestore(&sport->port.lock, flags);
527 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
528 uart_write_wakeup(&sport->port);
530 if (waitqueue_active(&sport->dma_wait)) {
531 wake_up(&sport->dma_wait);
532 dev_dbg(sport->port.dev, "exit in %s.\n", __func__);
536 spin_lock_irqsave(&sport->port.lock, flags);
537 if (!uart_circ_empty(xmit) && !uart_tx_stopped(&sport->port))
539 spin_unlock_irqrestore(&sport->port.lock, flags);
542 static void imx_dma_tx(struct imx_port *sport)
544 struct circ_buf *xmit = &sport->port.state->xmit;
545 struct scatterlist *sgl = sport->tx_sgl;
546 struct dma_async_tx_descriptor *desc;
547 struct dma_chan *chan = sport->dma_chan_tx;
548 struct device *dev = sport->port.dev;
552 if (sport->dma_is_txing)
555 sport->tx_bytes = uart_circ_chars_pending(xmit);
557 if (xmit->tail < xmit->head) {
558 sport->dma_tx_nents = 1;
559 sg_init_one(sgl, xmit->buf + xmit->tail, sport->tx_bytes);
561 sport->dma_tx_nents = 2;
562 sg_init_table(sgl, 2);
563 sg_set_buf(sgl, xmit->buf + xmit->tail,
564 UART_XMIT_SIZE - xmit->tail);
565 sg_set_buf(sgl + 1, xmit->buf, xmit->head);
568 ret = dma_map_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
570 dev_err(dev, "DMA mapping error for TX.\n");
573 desc = dmaengine_prep_slave_sg(chan, sgl, sport->dma_tx_nents,
574 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
576 dma_unmap_sg(dev, sgl, sport->dma_tx_nents,
578 dev_err(dev, "We cannot prepare for the TX slave dma!\n");
581 desc->callback = dma_tx_callback;
582 desc->callback_param = sport;
584 dev_dbg(dev, "TX: prepare to send %lu bytes by DMA.\n",
585 uart_circ_chars_pending(xmit));
587 temp = readl(sport->port.membase + UCR1);
589 writel(temp, sport->port.membase + UCR1);
592 sport->dma_is_txing = 1;
593 dmaengine_submit(desc);
594 dma_async_issue_pending(chan);
599 * interrupts disabled on entry
601 static void imx_start_tx(struct uart_port *port)
603 struct imx_port *sport = (struct imx_port *)port;
606 if (USE_IRDA(sport)) {
607 /* half duplex in IrDA mode; have to disable receive mode */
608 temp = readl(sport->port.membase + UCR4);
609 temp &= ~(UCR4_DREN);
610 writel(temp, sport->port.membase + UCR4);
612 temp = readl(sport->port.membase + UCR1);
613 temp &= ~(UCR1_RRDYEN);
614 writel(temp, sport->port.membase + UCR1);
617 if (!sport->dma_is_enabled) {
618 temp = readl(sport->port.membase + UCR1);
619 writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
622 if (USE_IRDA(sport)) {
623 temp = readl(sport->port.membase + UCR1);
625 writel(temp, sport->port.membase + UCR1);
627 temp = readl(sport->port.membase + UCR4);
629 writel(temp, sport->port.membase + UCR4);
632 if (sport->dma_is_enabled) {
633 /* FIXME: port->x_char must be transmitted if != 0 */
634 if (!uart_circ_empty(&port->state->xmit) &&
635 !uart_tx_stopped(port))
641 static irqreturn_t imx_rtsint(int irq, void *dev_id)
643 struct imx_port *sport = dev_id;
647 spin_lock_irqsave(&sport->port.lock, flags);
649 writel(USR1_RTSD, sport->port.membase + USR1);
650 val = readl(sport->port.membase + USR1) & USR1_RTSS;
651 uart_handle_cts_change(&sport->port, !!val);
652 wake_up_interruptible(&sport->port.state->port.delta_msr_wait);
654 spin_unlock_irqrestore(&sport->port.lock, flags);
658 static irqreturn_t imx_txint(int irq, void *dev_id)
660 struct imx_port *sport = dev_id;
663 spin_lock_irqsave(&sport->port.lock, flags);
664 imx_transmit_buffer(sport);
665 spin_unlock_irqrestore(&sport->port.lock, flags);
669 static irqreturn_t imx_rxint(int irq, void *dev_id)
671 struct imx_port *sport = dev_id;
672 unsigned int rx, flg, ignored = 0;
673 struct tty_port *port = &sport->port.state->port;
674 unsigned long flags, temp;
676 spin_lock_irqsave(&sport->port.lock, flags);
678 while (readl(sport->port.membase + USR2) & USR2_RDR) {
680 sport->port.icount.rx++;
682 rx = readl(sport->port.membase + URXD0);
684 temp = readl(sport->port.membase + USR2);
685 if (temp & USR2_BRCD) {
686 writel(USR2_BRCD, sport->port.membase + USR2);
687 if (uart_handle_break(&sport->port))
691 if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
694 if (unlikely(rx & URXD_ERR)) {
696 sport->port.icount.brk++;
697 else if (rx & URXD_PRERR)
698 sport->port.icount.parity++;
699 else if (rx & URXD_FRMERR)
700 sport->port.icount.frame++;
701 if (rx & URXD_OVRRUN)
702 sport->port.icount.overrun++;
704 if (rx & sport->port.ignore_status_mask) {
710 rx &= sport->port.read_status_mask;
714 else if (rx & URXD_PRERR)
716 else if (rx & URXD_FRMERR)
718 if (rx & URXD_OVRRUN)
722 sport->port.sysrq = 0;
726 if (sport->port.ignore_status_mask & URXD_DUMMY_READ)
729 tty_insert_flip_char(port, rx, flg);
733 spin_unlock_irqrestore(&sport->port.lock, flags);
734 tty_flip_buffer_push(port);
738 static int start_rx_dma(struct imx_port *sport);
740 * If the RXFIFO is filled with some data, and then we
741 * arise a DMA operation to receive them.
743 static void imx_dma_rxint(struct imx_port *sport)
748 spin_lock_irqsave(&sport->port.lock, flags);
750 temp = readl(sport->port.membase + USR2);
751 if ((temp & USR2_RDR) && !sport->dma_is_rxing) {
752 sport->dma_is_rxing = 1;
754 /* disable the `Recerver Ready Interrrupt` */
755 temp = readl(sport->port.membase + UCR1);
756 temp &= ~(UCR1_RRDYEN);
757 writel(temp, sport->port.membase + UCR1);
759 /* tell the DMA to receive the data. */
763 spin_unlock_irqrestore(&sport->port.lock, flags);
766 static irqreturn_t imx_int(int irq, void *dev_id)
768 struct imx_port *sport = dev_id;
772 sts = readl(sport->port.membase + USR1);
774 if (sts & USR1_RRDY) {
775 if (sport->dma_is_enabled)
776 imx_dma_rxint(sport);
778 imx_rxint(irq, dev_id);
781 if (sts & USR1_TRDY &&
782 readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN)
783 imx_txint(irq, dev_id);
786 imx_rtsint(irq, dev_id);
788 if (sts & USR1_AWAKE)
789 writel(USR1_AWAKE, sport->port.membase + USR1);
791 sts2 = readl(sport->port.membase + USR2);
792 if (sts2 & USR2_ORE) {
793 dev_err(sport->port.dev, "Rx FIFO overrun\n");
794 sport->port.icount.overrun++;
795 writel(sts2 | USR2_ORE, sport->port.membase + USR2);
802 * Return TIOCSER_TEMT when transmitter is not busy.
804 static unsigned int imx_tx_empty(struct uart_port *port)
806 struct imx_port *sport = (struct imx_port *)port;
809 ret = (readl(sport->port.membase + USR2) & USR2_TXDC) ? TIOCSER_TEMT : 0;
811 /* If the TX DMA is working, return 0. */
812 if (sport->dma_is_enabled && sport->dma_is_txing)
819 * We have a modem side uart, so the meanings of RTS and CTS are inverted.
821 static unsigned int imx_get_mctrl(struct uart_port *port)
823 struct imx_port *sport = (struct imx_port *)port;
824 unsigned int tmp = TIOCM_DSR | TIOCM_CAR;
826 if (readl(sport->port.membase + USR1) & USR1_RTSS)
829 if (readl(sport->port.membase + UCR2) & UCR2_CTS)
832 if (readl(sport->port.membase + uts_reg(sport)) & UTS_LOOP)
838 static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
840 struct imx_port *sport = (struct imx_port *)port;
843 temp = readl(sport->port.membase + UCR2) & ~(UCR2_CTS | UCR2_CTSC);
844 if (mctrl & TIOCM_RTS)
845 temp |= UCR2_CTS | UCR2_CTSC;
847 writel(temp, sport->port.membase + UCR2);
849 temp = readl(sport->port.membase + uts_reg(sport)) & ~UTS_LOOP;
850 if (mctrl & TIOCM_LOOP)
852 writel(temp, sport->port.membase + uts_reg(sport));
856 * Interrupts always disabled.
858 static void imx_break_ctl(struct uart_port *port, int break_state)
860 struct imx_port *sport = (struct imx_port *)port;
861 unsigned long flags, temp;
863 spin_lock_irqsave(&sport->port.lock, flags);
865 temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK;
867 if (break_state != 0)
870 writel(temp, sport->port.membase + UCR1);
872 spin_unlock_irqrestore(&sport->port.lock, flags);
875 #define TXTL 2 /* reset default */
876 #define RXTL 1 /* reset default */
878 static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
882 /* set receiver / transmitter trigger level */
883 val = readl(sport->port.membase + UFCR) & (UFCR_RFDIV | UFCR_DCEDTE);
884 val |= TXTL << UFCR_TXTL_SHF | RXTL;
885 writel(val, sport->port.membase + UFCR);
889 #define RX_BUF_SIZE (PAGE_SIZE)
890 static void imx_rx_dma_done(struct imx_port *sport)
895 spin_lock_irqsave(&sport->port.lock, flags);
897 /* Enable this interrupt when the RXFIFO is empty. */
898 temp = readl(sport->port.membase + UCR1);
900 writel(temp, sport->port.membase + UCR1);
902 sport->dma_is_rxing = 0;
904 /* Is the shutdown waiting for us? */
905 if (waitqueue_active(&sport->dma_wait))
906 wake_up(&sport->dma_wait);
908 spin_unlock_irqrestore(&sport->port.lock, flags);
912 * There are three kinds of RX DMA interrupts(such as in the MX6Q):
913 * [1] the RX DMA buffer is full.
914 * [2] the Aging timer expires(wait for 8 bytes long)
915 * [3] the Idle Condition Detect(enabled the UCR4_IDDMAEN).
917 * The [2] is trigger when a character was been sitting in the FIFO
918 * meanwhile [3] can wait for 32 bytes long when the RX line is
919 * on IDLE state and RxFIFO is empty.
921 static void dma_rx_callback(void *data)
923 struct imx_port *sport = data;
924 struct dma_chan *chan = sport->dma_chan_rx;
925 struct scatterlist *sgl = &sport->rx_sgl;
926 struct tty_port *port = &sport->port.state->port;
927 struct dma_tx_state state;
928 enum dma_status status;
932 dma_unmap_sg(sport->port.dev, sgl, 1, DMA_FROM_DEVICE);
934 status = dmaengine_tx_status(chan, (dma_cookie_t)0, &state);
935 count = RX_BUF_SIZE - state.residue;
936 dev_dbg(sport->port.dev, "We get %d bytes.\n", count);
939 if (!(sport->port.ignore_status_mask & URXD_DUMMY_READ))
940 tty_insert_flip_string(port, sport->rx_buf, count);
941 tty_flip_buffer_push(port);
944 } else if (readl(sport->port.membase + USR2) & USR2_RDR) {
946 * start rx_dma directly once data in RXFIFO, more efficient
948 * 1. call imx_rx_dma_done to stop dma if no data received
949 * 2. wait next RDR interrupt to start dma transfer.
954 * stop dma to prevent too many IDLE event trigged if no data
957 imx_rx_dma_done(sport);
961 static int start_rx_dma(struct imx_port *sport)
963 struct scatterlist *sgl = &sport->rx_sgl;
964 struct dma_chan *chan = sport->dma_chan_rx;
965 struct device *dev = sport->port.dev;
966 struct dma_async_tx_descriptor *desc;
969 sg_init_one(sgl, sport->rx_buf, RX_BUF_SIZE);
970 ret = dma_map_sg(dev, sgl, 1, DMA_FROM_DEVICE);
972 dev_err(dev, "DMA mapping error for RX.\n");
975 desc = dmaengine_prep_slave_sg(chan, sgl, 1, DMA_DEV_TO_MEM,
978 dma_unmap_sg(dev, sgl, 1, DMA_FROM_DEVICE);
979 dev_err(dev, "We cannot prepare for the RX slave dma!\n");
982 desc->callback = dma_rx_callback;
983 desc->callback_param = sport;
985 dev_dbg(dev, "RX: prepare for the DMA.\n");
986 dmaengine_submit(desc);
987 dma_async_issue_pending(chan);
991 static void imx_uart_dma_exit(struct imx_port *sport)
993 if (sport->dma_chan_rx) {
994 dma_release_channel(sport->dma_chan_rx);
995 sport->dma_chan_rx = NULL;
997 kfree(sport->rx_buf);
998 sport->rx_buf = NULL;
1001 if (sport->dma_chan_tx) {
1002 dma_release_channel(sport->dma_chan_tx);
1003 sport->dma_chan_tx = NULL;
1006 sport->dma_is_inited = 0;
1009 static int imx_uart_dma_init(struct imx_port *sport)
1011 struct dma_slave_config slave_config = {};
1012 struct device *dev = sport->port.dev;
1015 /* Prepare for RX : */
1016 sport->dma_chan_rx = dma_request_slave_channel(dev, "rx");
1017 if (!sport->dma_chan_rx) {
1018 dev_dbg(dev, "cannot get the DMA channel.\n");
1023 slave_config.direction = DMA_DEV_TO_MEM;
1024 slave_config.src_addr = sport->port.mapbase + URXD0;
1025 slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1026 slave_config.src_maxburst = RXTL;
1027 ret = dmaengine_slave_config(sport->dma_chan_rx, &slave_config);
1029 dev_err(dev, "error in RX dma configuration.\n");
1033 sport->rx_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
1034 if (!sport->rx_buf) {
1039 /* Prepare for TX : */
1040 sport->dma_chan_tx = dma_request_slave_channel(dev, "tx");
1041 if (!sport->dma_chan_tx) {
1042 dev_err(dev, "cannot get the TX DMA channel!\n");
1047 slave_config.direction = DMA_MEM_TO_DEV;
1048 slave_config.dst_addr = sport->port.mapbase + URTX0;
1049 slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1050 slave_config.dst_maxburst = TXTL;
1051 ret = dmaengine_slave_config(sport->dma_chan_tx, &slave_config);
1053 dev_err(dev, "error in TX dma configuration.");
1057 sport->dma_is_inited = 1;
1061 imx_uart_dma_exit(sport);
1065 static void imx_enable_dma(struct imx_port *sport)
1069 init_waitqueue_head(&sport->dma_wait);
1072 temp = readl(sport->port.membase + UCR1);
1073 temp |= UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN |
1074 /* wait for 32 idle frames for IDDMA interrupt */
1076 writel(temp, sport->port.membase + UCR1);
1079 temp = readl(sport->port.membase + UCR4);
1080 temp |= UCR4_IDDMAEN;
1081 writel(temp, sport->port.membase + UCR4);
1083 sport->dma_is_enabled = 1;
1086 static void imx_disable_dma(struct imx_port *sport)
1091 temp = readl(sport->port.membase + UCR1);
1092 temp &= ~(UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN);
1093 writel(temp, sport->port.membase + UCR1);
1096 temp = readl(sport->port.membase + UCR2);
1097 temp &= ~(UCR2_CTSC | UCR2_CTS);
1098 writel(temp, sport->port.membase + UCR2);
1101 temp = readl(sport->port.membase + UCR4);
1102 temp &= ~UCR4_IDDMAEN;
1103 writel(temp, sport->port.membase + UCR4);
1105 sport->dma_is_enabled = 0;
1108 /* half the RX buffer size */
1111 static int imx_startup(struct uart_port *port)
1113 struct imx_port *sport = (struct imx_port *)port;
1115 unsigned long flags, temp;
1117 retval = clk_prepare_enable(sport->clk_per);
1120 retval = clk_prepare_enable(sport->clk_ipg);
1122 clk_disable_unprepare(sport->clk_per);
1126 imx_setup_ufcr(sport, 0);
1128 /* disable the DREN bit (Data Ready interrupt enable) before
1131 temp = readl(sport->port.membase + UCR4);
1133 if (USE_IRDA(sport))
1136 /* set the trigger level for CTS */
1137 temp &= ~(UCR4_CTSTL_MASK << UCR4_CTSTL_SHF);
1138 temp |= CTSTL << UCR4_CTSTL_SHF;
1140 writel(temp & ~UCR4_DREN, sport->port.membase + UCR4);
1142 /* Reset fifo's and state machines */
1145 temp = readl(sport->port.membase + UCR2);
1147 writel(temp, sport->port.membase + UCR2);
1149 while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) && (--i > 0))
1152 /* Can we enable the DMA support? */
1153 if (is_imx6q_uart(sport) && !uart_console(port) &&
1154 !sport->dma_is_inited)
1155 imx_uart_dma_init(sport);
1157 spin_lock_irqsave(&sport->port.lock, flags);
1159 * Finally, clear and enable interrupts
1161 writel(USR1_RTSD, sport->port.membase + USR1);
1163 if (sport->dma_is_inited && !sport->dma_is_enabled)
1164 imx_enable_dma(sport);
1166 temp = readl(sport->port.membase + UCR1);
1167 temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN;
1169 if (USE_IRDA(sport)) {
1171 temp &= ~(UCR1_RTSDEN);
1174 writel(temp, sport->port.membase + UCR1);
1176 /* Clear any pending ORE flag before enabling interrupt */
1177 temp = readl(sport->port.membase + USR2);
1178 writel(temp | USR2_ORE, sport->port.membase + USR2);
1180 temp = readl(sport->port.membase + UCR4);
1182 writel(temp, sport->port.membase + UCR4);
1184 temp = readl(sport->port.membase + UCR2);
1185 temp |= (UCR2_RXEN | UCR2_TXEN);
1186 if (!sport->have_rtscts)
1188 writel(temp, sport->port.membase + UCR2);
1190 if (!is_imx1_uart(sport)) {
1191 temp = readl(sport->port.membase + UCR3);
1192 temp |= IMX21_UCR3_RXDMUXSEL | UCR3_ADNIMP;
1193 writel(temp, sport->port.membase + UCR3);
1196 if (USE_IRDA(sport)) {
1197 temp = readl(sport->port.membase + UCR4);
1198 if (sport->irda_inv_rx)
1201 temp &= ~(UCR4_INVR);
1202 writel(temp | UCR4_DREN, sport->port.membase + UCR4);
1204 temp = readl(sport->port.membase + UCR3);
1205 if (sport->irda_inv_tx)
1208 temp &= ~(UCR3_INVT);
1209 writel(temp, sport->port.membase + UCR3);
1213 * Enable modem status interrupts
1215 imx_enable_ms(&sport->port);
1216 spin_unlock_irqrestore(&sport->port.lock, flags);
1218 if (USE_IRDA(sport)) {
1219 struct imxuart_platform_data *pdata;
1220 pdata = dev_get_platdata(sport->port.dev);
1221 sport->irda_inv_rx = pdata->irda_inv_rx;
1222 sport->irda_inv_tx = pdata->irda_inv_tx;
1223 sport->trcv_delay = pdata->transceiver_delay;
1224 if (pdata->irda_enable)
1225 pdata->irda_enable(1);
1231 static void imx_shutdown(struct uart_port *port)
1233 struct imx_port *sport = (struct imx_port *)port;
1235 unsigned long flags;
1237 if (sport->dma_is_enabled) {
1240 /* We have to wait for the DMA to finish. */
1241 ret = wait_event_interruptible(sport->dma_wait,
1242 !sport->dma_is_rxing && !sport->dma_is_txing);
1244 sport->dma_is_rxing = 0;
1245 sport->dma_is_txing = 0;
1246 dmaengine_terminate_all(sport->dma_chan_tx);
1247 dmaengine_terminate_all(sport->dma_chan_rx);
1249 spin_lock_irqsave(&sport->port.lock, flags);
1252 imx_disable_dma(sport);
1253 spin_unlock_irqrestore(&sport->port.lock, flags);
1254 imx_uart_dma_exit(sport);
1257 spin_lock_irqsave(&sport->port.lock, flags);
1258 temp = readl(sport->port.membase + UCR2);
1259 temp &= ~(UCR2_TXEN);
1260 writel(temp, sport->port.membase + UCR2);
1261 spin_unlock_irqrestore(&sport->port.lock, flags);
1263 if (USE_IRDA(sport)) {
1264 struct imxuart_platform_data *pdata;
1265 pdata = dev_get_platdata(sport->port.dev);
1266 if (pdata->irda_enable)
1267 pdata->irda_enable(0);
1273 del_timer_sync(&sport->timer);
1276 * Disable all interrupts, port and break condition.
1279 spin_lock_irqsave(&sport->port.lock, flags);
1280 temp = readl(sport->port.membase + UCR1);
1281 temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN);
1282 if (USE_IRDA(sport))
1283 temp &= ~(UCR1_IREN);
1285 writel(temp, sport->port.membase + UCR1);
1286 spin_unlock_irqrestore(&sport->port.lock, flags);
1288 clk_disable_unprepare(sport->clk_per);
1289 clk_disable_unprepare(sport->clk_ipg);
1292 static void imx_flush_buffer(struct uart_port *port)
1294 struct imx_port *sport = (struct imx_port *)port;
1295 struct scatterlist *sgl = &sport->tx_sgl[0];
1298 if (!sport->dma_chan_tx)
1301 sport->tx_bytes = 0;
1302 dmaengine_terminate_all(sport->dma_chan_tx);
1303 if (sport->dma_is_txing) {
1304 dma_unmap_sg(sport->port.dev, sgl, sport->dma_tx_nents,
1306 temp = readl(sport->port.membase + UCR1);
1307 temp &= ~UCR1_TDMAEN;
1308 writel(temp, sport->port.membase + UCR1);
1309 sport->dma_is_txing = false;
1314 imx_set_termios(struct uart_port *port, struct ktermios *termios,
1315 struct ktermios *old)
1317 struct imx_port *sport = (struct imx_port *)port;
1318 unsigned long flags;
1319 unsigned int ucr2, old_ucr1, old_txrxen, baud, quot;
1320 unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1321 unsigned int div, ufcr;
1322 unsigned long num, denom;
1326 * If we don't support modem control lines, don't allow
1330 termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR);
1331 termios->c_cflag |= CLOCAL;
1335 * We only support CS7 and CS8.
1337 while ((termios->c_cflag & CSIZE) != CS7 &&
1338 (termios->c_cflag & CSIZE) != CS8) {
1339 termios->c_cflag &= ~CSIZE;
1340 termios->c_cflag |= old_csize;
1344 if ((termios->c_cflag & CSIZE) == CS8)
1345 ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS;
1347 ucr2 = UCR2_SRST | UCR2_IRTS;
1349 if (termios->c_cflag & CRTSCTS) {
1350 if (sport->have_rtscts) {
1354 termios->c_cflag &= ~CRTSCTS;
1358 if (termios->c_cflag & CSTOPB)
1360 if (termios->c_cflag & PARENB) {
1362 if (termios->c_cflag & PARODD)
1366 del_timer_sync(&sport->timer);
1369 * Ask the core to calculate the divisor for us.
1371 baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
1372 quot = uart_get_divisor(port, baud);
1374 spin_lock_irqsave(&sport->port.lock, flags);
1376 sport->port.read_status_mask = 0;
1377 if (termios->c_iflag & INPCK)
1378 sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR);
1379 if (termios->c_iflag & (BRKINT | PARMRK))
1380 sport->port.read_status_mask |= URXD_BRK;
1383 * Characters to ignore
1385 sport->port.ignore_status_mask = 0;
1386 if (termios->c_iflag & IGNPAR)
1387 sport->port.ignore_status_mask |= URXD_PRERR;
1388 if (termios->c_iflag & IGNBRK) {
1389 sport->port.ignore_status_mask |= URXD_BRK;
1391 * If we're ignoring parity and break indicators,
1392 * ignore overruns too (for real raw support).
1394 if (termios->c_iflag & IGNPAR)
1395 sport->port.ignore_status_mask |= URXD_OVRRUN;
1398 if ((termios->c_cflag & CREAD) == 0)
1399 sport->port.ignore_status_mask |= URXD_DUMMY_READ;
1402 * Update the per-port timeout.
1404 uart_update_timeout(port, termios->c_cflag, baud);
1407 * disable interrupts and drain transmitter
1409 old_ucr1 = readl(sport->port.membase + UCR1);
1410 writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN),
1411 sport->port.membase + UCR1);
1413 while (!(readl(sport->port.membase + USR2) & USR2_TXDC))
1416 /* then, disable everything */
1417 old_txrxen = readl(sport->port.membase + UCR2);
1418 writel(old_txrxen & ~(UCR2_TXEN | UCR2_RXEN),
1419 sport->port.membase + UCR2);
1420 old_txrxen &= (UCR2_TXEN | UCR2_RXEN);
1422 if (USE_IRDA(sport)) {
1424 * use maximum available submodule frequency to
1425 * avoid missing short pulses due to low sampling rate
1429 /* custom-baudrate handling */
1430 div = sport->port.uartclk / (baud * 16);
1431 if (baud == 38400 && quot != div)
1432 baud = sport->port.uartclk / (quot * 16);
1434 div = sport->port.uartclk / (baud * 16);
1441 rational_best_approximation(16 * div * baud, sport->port.uartclk,
1442 1 << 16, 1 << 16, &num, &denom);
1444 tdiv64 = sport->port.uartclk;
1446 do_div(tdiv64, denom * 16 * div);
1447 tty_termios_encode_baud_rate(termios,
1448 (speed_t)tdiv64, (speed_t)tdiv64);
1453 ufcr = readl(sport->port.membase + UFCR);
1454 ufcr = (ufcr & (~UFCR_RFDIV)) | UFCR_RFDIV_REG(div);
1455 if (sport->dte_mode)
1456 ufcr |= UFCR_DCEDTE;
1457 writel(ufcr, sport->port.membase + UFCR);
1459 writel(num, sport->port.membase + UBIR);
1460 writel(denom, sport->port.membase + UBMR);
1462 if (!is_imx1_uart(sport))
1463 writel(sport->port.uartclk / div / 1000,
1464 sport->port.membase + IMX21_ONEMS);
1466 writel(old_ucr1, sport->port.membase + UCR1);
1468 /* set the parity, stop bits and data size */
1469 writel(ucr2 | old_txrxen, sport->port.membase + UCR2);
1471 if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
1472 imx_enable_ms(&sport->port);
1474 spin_unlock_irqrestore(&sport->port.lock, flags);
1477 static const char *imx_type(struct uart_port *port)
1479 struct imx_port *sport = (struct imx_port *)port;
1481 return sport->port.type == PORT_IMX ? "IMX" : NULL;
1485 * Configure/autoconfigure the port.
1487 static void imx_config_port(struct uart_port *port, int flags)
1489 struct imx_port *sport = (struct imx_port *)port;
1491 if (flags & UART_CONFIG_TYPE)
1492 sport->port.type = PORT_IMX;
1496 * Verify the new serial_struct (for TIOCSSERIAL).
1497 * The only change we allow are to the flags and type, and
1498 * even then only between PORT_IMX and PORT_UNKNOWN
1501 imx_verify_port(struct uart_port *port, struct serial_struct *ser)
1503 struct imx_port *sport = (struct imx_port *)port;
1506 if (ser->type != PORT_UNKNOWN && ser->type != PORT_IMX)
1508 if (sport->port.irq != ser->irq)
1510 if (ser->io_type != UPIO_MEM)
1512 if (sport->port.uartclk / 16 != ser->baud_base)
1514 if (sport->port.mapbase != (unsigned long)ser->iomem_base)
1516 if (sport->port.iobase != ser->port)
1523 #if defined(CONFIG_CONSOLE_POLL)
1525 static int imx_poll_init(struct uart_port *port)
1527 struct imx_port *sport = (struct imx_port *)port;
1528 unsigned long flags;
1532 retval = clk_prepare_enable(sport->clk_ipg);
1535 retval = clk_prepare_enable(sport->clk_per);
1537 clk_disable_unprepare(sport->clk_ipg);
1539 imx_setup_ufcr(sport, 0);
1541 spin_lock_irqsave(&sport->port.lock, flags);
1543 temp = readl(sport->port.membase + UCR1);
1544 if (is_imx1_uart(sport))
1545 temp |= IMX1_UCR1_UARTCLKEN;
1546 temp |= UCR1_UARTEN | UCR1_RRDYEN;
1547 temp &= ~(UCR1_TXMPTYEN | UCR1_RTSDEN);
1548 writel(temp, sport->port.membase + UCR1);
1550 temp = readl(sport->port.membase + UCR2);
1552 writel(temp, sport->port.membase + UCR2);
1554 spin_unlock_irqrestore(&sport->port.lock, flags);
1559 static int imx_poll_get_char(struct uart_port *port)
1561 if (!(readl_relaxed(port->membase + USR2) & USR2_RDR))
1562 return NO_POLL_CHAR;
1564 return readl_relaxed(port->membase + URXD0) & URXD_RX_DATA;
1567 static void imx_poll_put_char(struct uart_port *port, unsigned char c)
1569 unsigned int status;
1573 status = readl_relaxed(port->membase + USR1);
1574 } while (~status & USR1_TRDY);
1577 writel_relaxed(c, port->membase + URTX0);
1581 status = readl_relaxed(port->membase + USR2);
1582 } while (~status & USR2_TXDC);
1586 static struct uart_ops imx_pops = {
1587 .tx_empty = imx_tx_empty,
1588 .set_mctrl = imx_set_mctrl,
1589 .get_mctrl = imx_get_mctrl,
1590 .stop_tx = imx_stop_tx,
1591 .start_tx = imx_start_tx,
1592 .stop_rx = imx_stop_rx,
1593 .enable_ms = imx_enable_ms,
1594 .break_ctl = imx_break_ctl,
1595 .startup = imx_startup,
1596 .shutdown = imx_shutdown,
1597 .flush_buffer = imx_flush_buffer,
1598 .set_termios = imx_set_termios,
1600 .config_port = imx_config_port,
1601 .verify_port = imx_verify_port,
1602 #if defined(CONFIG_CONSOLE_POLL)
1603 .poll_init = imx_poll_init,
1604 .poll_get_char = imx_poll_get_char,
1605 .poll_put_char = imx_poll_put_char,
1609 static struct imx_port *imx_ports[UART_NR];
1611 #ifdef CONFIG_SERIAL_IMX_CONSOLE
1612 static void imx_console_putchar(struct uart_port *port, int ch)
1614 struct imx_port *sport = (struct imx_port *)port;
1616 while (readl(sport->port.membase + uts_reg(sport)) & UTS_TXFULL)
1619 writel(ch, sport->port.membase + URTX0);
1623 * Interrupts are disabled on entering
1626 imx_console_write(struct console *co, const char *s, unsigned int count)
1628 struct imx_port *sport = imx_ports[co->index];
1629 struct imx_port_ucrs old_ucr;
1631 unsigned long flags = 0;
1635 retval = clk_enable(sport->clk_per);
1638 retval = clk_enable(sport->clk_ipg);
1640 clk_disable(sport->clk_per);
1644 if (sport->port.sysrq)
1646 else if (oops_in_progress)
1647 locked = spin_trylock_irqsave(&sport->port.lock, flags);
1649 spin_lock_irqsave(&sport->port.lock, flags);
1652 * First, save UCR1/2/3 and then disable interrupts
1654 imx_port_ucrs_save(&sport->port, &old_ucr);
1655 ucr1 = old_ucr.ucr1;
1657 if (is_imx1_uart(sport))
1658 ucr1 |= IMX1_UCR1_UARTCLKEN;
1659 ucr1 |= UCR1_UARTEN;
1660 ucr1 &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN);
1662 writel(ucr1, sport->port.membase + UCR1);
1664 writel(old_ucr.ucr2 | UCR2_TXEN, sport->port.membase + UCR2);
1666 uart_console_write(&sport->port, s, count, imx_console_putchar);
1669 * Finally, wait for transmitter to become empty
1670 * and restore UCR1/2/3
1672 while (!(readl(sport->port.membase + USR2) & USR2_TXDC));
1674 imx_port_ucrs_restore(&sport->port, &old_ucr);
1677 spin_unlock_irqrestore(&sport->port.lock, flags);
1679 clk_disable(sport->clk_ipg);
1680 clk_disable(sport->clk_per);
1684 * If the port was already initialised (eg, by a boot loader),
1685 * try to determine the current setup.
1688 imx_console_get_options(struct imx_port *sport, int *baud,
1689 int *parity, int *bits)
1692 if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) {
1693 /* ok, the port was enabled */
1694 unsigned int ucr2, ubir, ubmr, uartclk;
1695 unsigned int baud_raw;
1696 unsigned int ucfr_rfdiv;
1698 ucr2 = readl(sport->port.membase + UCR2);
1701 if (ucr2 & UCR2_PREN) {
1702 if (ucr2 & UCR2_PROE)
1713 ubir = readl(sport->port.membase + UBIR) & 0xffff;
1714 ubmr = readl(sport->port.membase + UBMR) & 0xffff;
1716 ucfr_rfdiv = (readl(sport->port.membase + UFCR) & UFCR_RFDIV) >> 7;
1717 if (ucfr_rfdiv == 6)
1720 ucfr_rfdiv = 6 - ucfr_rfdiv;
1722 uartclk = clk_get_rate(sport->clk_per);
1723 uartclk /= ucfr_rfdiv;
1726 * The next code provides exact computation of
1727 * baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1))
1728 * without need of float support or long long division,
1729 * which would be required to prevent 32bit arithmetic overflow
1731 unsigned int mul = ubir + 1;
1732 unsigned int div = 16 * (ubmr + 1);
1733 unsigned int rem = uartclk % div;
1735 baud_raw = (uartclk / div) * mul;
1736 baud_raw += (rem * mul + div / 2) / div;
1737 *baud = (baud_raw + 50) / 100 * 100;
1740 if (*baud != baud_raw)
1741 pr_info("Console IMX rounded baud rate from %d to %d\n",
1747 imx_console_setup(struct console *co, char *options)
1749 struct imx_port *sport;
1757 * Check whether an invalid uart number has been specified, and
1758 * if so, search for the first available port that does have
1761 if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports))
1763 sport = imx_ports[co->index];
1767 /* For setting the registers, we only need to enable the ipg clock. */
1768 retval = clk_prepare_enable(sport->clk_ipg);
1773 uart_parse_options(options, &baud, &parity, &bits, &flow);
1775 imx_console_get_options(sport, &baud, &parity, &bits);
1777 imx_setup_ufcr(sport, 0);
1779 retval = uart_set_options(&sport->port, co, baud, parity, bits, flow);
1781 clk_disable(sport->clk_ipg);
1783 clk_unprepare(sport->clk_ipg);
1787 retval = clk_prepare(sport->clk_per);
1789 clk_disable_unprepare(sport->clk_ipg);
1795 static struct uart_driver imx_reg;
1796 static struct console imx_console = {
1798 .write = imx_console_write,
1799 .device = uart_console_device,
1800 .setup = imx_console_setup,
1801 .flags = CON_PRINTBUFFER,
1806 #define IMX_CONSOLE &imx_console
1808 #define IMX_CONSOLE NULL
1811 static struct uart_driver imx_reg = {
1812 .owner = THIS_MODULE,
1813 .driver_name = DRIVER_NAME,
1814 .dev_name = DEV_NAME,
1815 .major = SERIAL_IMX_MAJOR,
1816 .minor = MINOR_START,
1817 .nr = ARRAY_SIZE(imx_ports),
1818 .cons = IMX_CONSOLE,
1821 static int serial_imx_suspend(struct platform_device *dev, pm_message_t state)
1823 struct imx_port *sport = platform_get_drvdata(dev);
1826 /* enable wakeup from i.MX UART */
1827 val = readl(sport->port.membase + UCR3);
1829 writel(val, sport->port.membase + UCR3);
1831 uart_suspend_port(&imx_reg, &sport->port);
1836 static int serial_imx_resume(struct platform_device *dev)
1838 struct imx_port *sport = platform_get_drvdata(dev);
1841 /* disable wakeup from i.MX UART */
1842 val = readl(sport->port.membase + UCR3);
1843 val &= ~UCR3_AWAKEN;
1844 writel(val, sport->port.membase + UCR3);
1846 uart_resume_port(&imx_reg, &sport->port);
1853 * This function returns 1 iff pdev isn't a device instatiated by dt, 0 iff it
1854 * could successfully get all information from dt or a negative errno.
1856 static int serial_imx_probe_dt(struct imx_port *sport,
1857 struct platform_device *pdev)
1859 struct device_node *np = pdev->dev.of_node;
1860 const struct of_device_id *of_id =
1861 of_match_device(imx_uart_dt_ids, &pdev->dev);
1865 /* no device tree device */
1868 ret = of_alias_get_id(np, "serial");
1870 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
1873 sport->port.line = ret;
1875 if (of_get_property(np, "fsl,uart-has-rtscts", NULL))
1876 sport->have_rtscts = 1;
1878 if (of_get_property(np, "fsl,irda-mode", NULL))
1879 sport->use_irda = 1;
1881 if (of_get_property(np, "fsl,dte-mode", NULL))
1882 sport->dte_mode = 1;
1884 sport->devdata = of_id->data;
1889 static inline int serial_imx_probe_dt(struct imx_port *sport,
1890 struct platform_device *pdev)
1896 static void serial_imx_probe_pdata(struct imx_port *sport,
1897 struct platform_device *pdev)
1899 struct imxuart_platform_data *pdata = dev_get_platdata(&pdev->dev);
1901 sport->port.line = pdev->id;
1902 sport->devdata = (struct imx_uart_data *) pdev->id_entry->driver_data;
1907 if (pdata->flags & IMXUART_HAVE_RTSCTS)
1908 sport->have_rtscts = 1;
1910 if (pdata->flags & IMXUART_IRDA)
1911 sport->use_irda = 1;
1914 static int serial_imx_probe(struct platform_device *pdev)
1916 struct imx_port *sport;
1919 struct resource *res;
1921 sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
1925 ret = serial_imx_probe_dt(sport, pdev);
1927 serial_imx_probe_pdata(sport, pdev);
1931 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1932 base = devm_ioremap_resource(&pdev->dev, res);
1934 return PTR_ERR(base);
1936 sport->port.dev = &pdev->dev;
1937 sport->port.mapbase = res->start;
1938 sport->port.membase = base;
1939 sport->port.type = PORT_IMX,
1940 sport->port.iotype = UPIO_MEM;
1941 sport->port.irq = platform_get_irq(pdev, 0);
1942 sport->rxirq = platform_get_irq(pdev, 0);
1943 sport->txirq = platform_get_irq(pdev, 1);
1944 sport->rtsirq = platform_get_irq(pdev, 2);
1945 sport->port.fifosize = 32;
1946 sport->port.ops = &imx_pops;
1947 sport->port.flags = UPF_BOOT_AUTOCONF;
1948 init_timer(&sport->timer);
1949 sport->timer.function = imx_timeout;
1950 sport->timer.data = (unsigned long)sport;
1952 sport->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1953 if (IS_ERR(sport->clk_ipg)) {
1954 ret = PTR_ERR(sport->clk_ipg);
1955 dev_err(&pdev->dev, "failed to get ipg clk: %d\n", ret);
1959 sport->clk_per = devm_clk_get(&pdev->dev, "per");
1960 if (IS_ERR(sport->clk_per)) {
1961 ret = PTR_ERR(sport->clk_per);
1962 dev_err(&pdev->dev, "failed to get per clk: %d\n", ret);
1966 sport->port.uartclk = clk_get_rate(sport->clk_per);
1969 * Allocate the IRQ(s) i.MX1 has three interrupts whereas later
1970 * chips only have one interrupt.
1972 if (sport->txirq > 0) {
1973 ret = devm_request_irq(&pdev->dev, sport->rxirq, imx_rxint, 0,
1974 dev_name(&pdev->dev), sport);
1978 ret = devm_request_irq(&pdev->dev, sport->txirq, imx_txint, 0,
1979 dev_name(&pdev->dev), sport);
1983 /* do not use RTS IRQ on IrDA */
1984 if (!USE_IRDA(sport)) {
1985 ret = devm_request_irq(&pdev->dev, sport->rtsirq,
1987 dev_name(&pdev->dev), sport);
1992 ret = devm_request_irq(&pdev->dev, sport->port.irq, imx_int, 0,
1993 dev_name(&pdev->dev), sport);
1998 imx_ports[sport->port.line] = sport;
2000 platform_set_drvdata(pdev, sport);
2002 return uart_add_one_port(&imx_reg, &sport->port);
2005 static int serial_imx_remove(struct platform_device *pdev)
2007 struct imx_port *sport = platform_get_drvdata(pdev);
2009 return uart_remove_one_port(&imx_reg, &sport->port);
2012 static struct platform_driver serial_imx_driver = {
2013 .probe = serial_imx_probe,
2014 .remove = serial_imx_remove,
2016 .suspend = serial_imx_suspend,
2017 .resume = serial_imx_resume,
2018 .id_table = imx_uart_devtype,
2021 .of_match_table = imx_uart_dt_ids,
2025 static int __init imx_serial_init(void)
2027 int ret = uart_register_driver(&imx_reg);
2032 ret = platform_driver_register(&serial_imx_driver);
2034 uart_unregister_driver(&imx_reg);
2039 static void __exit imx_serial_exit(void)
2041 platform_driver_unregister(&serial_imx_driver);
2042 uart_unregister_driver(&imx_reg);
2045 module_init(imx_serial_init);
2046 module_exit(imx_serial_exit);
2048 MODULE_AUTHOR("Sascha Hauer");
2049 MODULE_DESCRIPTION("IMX generic serial port driver");
2050 MODULE_LICENSE("GPL");
2051 MODULE_ALIAS("platform:imx-uart");