2 * mfd.c: driver for High Speed UART device of Intel Medfield platform
4 * Refer pxa.c, 8250.c and some other drivers in drivers/serial/
6 * (C) Copyright 2010 Intel Corporation
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; version 2
15 * 1. DMA channel allocation: 0/1 channel are assigned to port 0,
16 * 2/3 chan to port 1, 4/5 chan to port 3. Even number chans
17 * are used for RX, odd chans for TX
19 * 2. In A0 stepping, UART will not support TX half empty flag
21 * 3. The RI/DSR/DCD/DTR are not pinned out, DCD & DSR are always
22 * asserted, only when the HW is reset the DDCD and DDSR will
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/console.h>
29 #include <linux/sysrq.h>
30 #include <linux/serial_reg.h>
31 #include <linux/circ_buf.h>
32 #include <linux/delay.h>
33 #include <linux/interrupt.h>
34 #include <linux/tty.h>
35 #include <linux/tty_flip.h>
36 #include <linux/serial_core.h>
37 #include <linux/serial_mfd.h>
38 #include <linux/dma-mapping.h>
39 #include <linux/pci.h>
41 #include <linux/debugfs.h>
43 #define MFD_HSU_A0_STEPPING 1
45 #define HSU_DMA_BUF_SIZE 2048
47 #define chan_readl(chan, offset) readl(chan->reg + offset)
48 #define chan_writel(chan, offset, val) writel(val, chan->reg + offset)
50 #define mfd_readl(obj, offset) readl(obj->reg + offset)
51 #define mfd_writel(obj, offset, val) writel(val, obj->reg + offset)
53 #define HSU_DMA_TIMEOUT_CHECK_FREQ (HZ/10)
55 struct hsu_dma_buffer {
64 enum dma_data_direction dirt;
65 struct uart_hsu_port *uport;
67 struct timer_list rx_timer; /* only needed by RX channel */
70 struct uart_hsu_port {
71 struct uart_port port;
75 unsigned int lsr_break_flag;
80 struct hsu_dma_chan *txc;
81 struct hsu_dma_chan *rxc;
82 struct hsu_dma_buffer txbuf;
83 struct hsu_dma_buffer rxbuf;
84 int use_dma; /* flag for DMA/PIO */
89 /* Top level data structure of HSU */
96 struct uart_hsu_port port[3];
97 struct hsu_dma_chan chans[10];
99 struct dentry *debugfs;
102 static inline unsigned int serial_in(struct uart_hsu_port *up, int offset)
106 if (offset > UART_MSR) {
108 val = readl(up->port.membase + offset);
110 val = (unsigned int)readb(up->port.membase + offset);
115 static inline void serial_out(struct uart_hsu_port *up, int offset, int value)
117 if (offset > UART_MSR) {
119 writel(value, up->port.membase + offset);
121 unsigned char val = value & 0xff;
122 writeb(val, up->port.membase + offset);
126 #ifdef CONFIG_DEBUG_FS
128 #define HSU_REGS_BUFSIZE 1024
130 static int hsu_show_regs_open(struct inode *inode, struct file *file)
132 file->private_data = inode->i_private;
136 static ssize_t port_show_regs(struct file *file, char __user *user_buf,
137 size_t count, loff_t *ppos)
139 struct uart_hsu_port *up = file->private_data;
144 buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL);
148 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
149 "MFD HSU port[%d] regs:\n", up->index);
151 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
152 "=================================\n");
153 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
154 "IER: \t\t0x%08x\n", serial_in(up, UART_IER));
155 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
156 "IIR: \t\t0x%08x\n", serial_in(up, UART_IIR));
157 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
158 "LCR: \t\t0x%08x\n", serial_in(up, UART_LCR));
159 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
160 "MCR: \t\t0x%08x\n", serial_in(up, UART_MCR));
161 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
162 "LSR: \t\t0x%08x\n", serial_in(up, UART_LSR));
163 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
164 "MSR: \t\t0x%08x\n", serial_in(up, UART_MSR));
165 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
166 "FOR: \t\t0x%08x\n", serial_in(up, UART_FOR));
167 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
168 "PS: \t\t0x%08x\n", serial_in(up, UART_PS));
169 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
170 "MUL: \t\t0x%08x\n", serial_in(up, UART_MUL));
171 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
172 "DIV: \t\t0x%08x\n", serial_in(up, UART_DIV));
174 ret = simple_read_from_buffer(user_buf, count, ppos, buf, len);
179 static ssize_t dma_show_regs(struct file *file, char __user *user_buf,
180 size_t count, loff_t *ppos)
182 struct hsu_dma_chan *chan = file->private_data;
187 buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL);
191 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
192 "MFD HSU DMA channel [%d] regs:\n", chan->id);
194 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
195 "=================================\n");
196 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
197 "CR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_CR));
198 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
199 "DCR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_DCR));
200 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
201 "BSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_BSR));
202 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
203 "MOTSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_MOTSR));
204 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
205 "D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0SAR));
206 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
207 "D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0TSR));
208 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
209 "D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1SAR));
210 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
211 "D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1TSR));
212 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
213 "D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2SAR));
214 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
215 "D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2TSR));
216 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
217 "D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3SAR));
218 len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
219 "D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3TSR));
221 ret = simple_read_from_buffer(user_buf, count, ppos, buf, len);
226 static const struct file_operations port_regs_ops = {
227 .owner = THIS_MODULE,
228 .open = hsu_show_regs_open,
229 .read = port_show_regs,
232 static const struct file_operations dma_regs_ops = {
233 .owner = THIS_MODULE,
234 .open = hsu_show_regs_open,
235 .read = dma_show_regs,
238 static int hsu_debugfs_init(struct hsu_port *hsu)
243 hsu->debugfs = debugfs_create_dir("hsu", NULL);
247 for (i = 0; i < 3; i++) {
248 snprintf(name, sizeof(name), "port_%d_regs", i);
249 debugfs_create_file(name, S_IFREG | S_IRUGO,
250 hsu->debugfs, (void *)(&hsu->port[i]), &port_regs_ops);
253 for (i = 0; i < 6; i++) {
254 snprintf(name, sizeof(name), "dma_chan_%d_regs", i);
255 debugfs_create_file(name, S_IFREG | S_IRUGO,
256 hsu->debugfs, (void *)&hsu->chans[i], &dma_regs_ops);
262 static void hsu_debugfs_remove(struct hsu_port *hsu)
265 debugfs_remove_recursive(hsu->debugfs);
269 static inline int hsu_debugfs_init(struct hsu_port *hsu)
274 static inline void hsu_debugfs_remove(struct hsu_port *hsu)
277 #endif /* CONFIG_DEBUG_FS */
279 static void serial_hsu_enable_ms(struct uart_port *port)
281 struct uart_hsu_port *up =
282 container_of(port, struct uart_hsu_port, port);
284 up->ier |= UART_IER_MSI;
285 serial_out(up, UART_IER, up->ier);
288 void hsu_dma_tx(struct uart_hsu_port *up)
290 struct circ_buf *xmit = &up->port.state->xmit;
291 struct hsu_dma_buffer *dbuf = &up->txbuf;
294 /* test_and_set_bit may be better, but anyway it's in lock protected mode */
298 /* Update the circ buf info */
299 xmit->tail += dbuf->ofs;
300 xmit->tail &= UART_XMIT_SIZE - 1;
302 up->port.icount.tx += dbuf->ofs;
305 /* Disable the channel */
306 chan_writel(up->txc, HSU_CH_CR, 0x0);
308 if (!uart_circ_empty(xmit) && !uart_tx_stopped(&up->port)) {
309 dma_sync_single_for_device(up->port.dev,
314 count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
317 /* Reprogram the channel */
318 chan_writel(up->txc, HSU_CH_D0SAR, dbuf->dma_addr + xmit->tail);
319 chan_writel(up->txc, HSU_CH_D0TSR, count);
321 /* Reenable the channel */
322 chan_writel(up->txc, HSU_CH_DCR, 0x1
327 chan_writel(up->txc, HSU_CH_CR, 0x1);
330 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
331 uart_write_wakeup(&up->port);
334 /* The buffer is already cache coherent */
335 void hsu_dma_start_rx_chan(struct hsu_dma_chan *rxc, struct hsu_dma_buffer *dbuf)
339 chan_writel(rxc, HSU_CH_BSR, 32);
340 chan_writel(rxc, HSU_CH_MOTSR, 4);
342 chan_writel(rxc, HSU_CH_D0SAR, dbuf->dma_addr);
343 chan_writel(rxc, HSU_CH_D0TSR, dbuf->dma_size);
344 chan_writel(rxc, HSU_CH_DCR, 0x1 | (0x1 << 8)
346 | (0x1 << 24) /* timeout bit, see HSU Errata 1 */
348 chan_writel(rxc, HSU_CH_CR, 0x3);
350 mod_timer(&rxc->rx_timer, jiffies + HSU_DMA_TIMEOUT_CHECK_FREQ);
353 /* Protected by spin_lock_irqsave(port->lock) */
354 static void serial_hsu_start_tx(struct uart_port *port)
356 struct uart_hsu_port *up =
357 container_of(port, struct uart_hsu_port, port);
361 } else if (!(up->ier & UART_IER_THRI)) {
362 up->ier |= UART_IER_THRI;
363 serial_out(up, UART_IER, up->ier);
367 static void serial_hsu_stop_tx(struct uart_port *port)
369 struct uart_hsu_port *up =
370 container_of(port, struct uart_hsu_port, port);
371 struct hsu_dma_chan *txc = up->txc;
374 chan_writel(txc, HSU_CH_CR, 0x0);
375 else if (up->ier & UART_IER_THRI) {
376 up->ier &= ~UART_IER_THRI;
377 serial_out(up, UART_IER, up->ier);
381 /* This is always called in spinlock protected mode, so
382 * modify timeout timer is safe here */
383 void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts)
385 struct hsu_dma_buffer *dbuf = &up->rxbuf;
386 struct hsu_dma_chan *chan = up->rxc;
387 struct uart_port *port = &up->port;
388 struct tty_struct *tty = port->state->port.tty;
395 * First need to know how many is already transferred,
396 * then check if its a timeout DMA irq, and return
397 * the trail bytes out, push them up and reenable the
401 /* Timeout IRQ, need wait some time, see Errata 2 */
405 /* Stop the channel */
406 chan_writel(chan, HSU_CH_CR, 0x0);
408 count = chan_readl(chan, HSU_CH_D0SAR) - dbuf->dma_addr;
410 /* Restart the channel before we leave */
411 chan_writel(chan, HSU_CH_CR, 0x3);
414 del_timer(&chan->rx_timer);
416 dma_sync_single_for_cpu(port->dev, dbuf->dma_addr,
417 dbuf->dma_size, DMA_FROM_DEVICE);
420 * Head will only wrap around when we recycle
421 * the DMA buffer, and when that happens, we
422 * explicitly set tail to 0. So head will
423 * always be greater than tail.
425 tty_insert_flip_string(tty, dbuf->buf, count);
426 port->icount.rx += count;
428 dma_sync_single_for_device(up->port.dev, dbuf->dma_addr,
429 dbuf->dma_size, DMA_FROM_DEVICE);
431 /* Reprogram the channel */
432 chan_writel(chan, HSU_CH_D0SAR, dbuf->dma_addr);
433 chan_writel(chan, HSU_CH_D0TSR, dbuf->dma_size);
434 chan_writel(chan, HSU_CH_DCR, 0x1
437 | (0x1 << 24) /* timeout bit, see HSU Errata 1 */
439 tty_flip_buffer_push(tty);
441 chan_writel(chan, HSU_CH_CR, 0x3);
442 chan->rx_timer.expires = jiffies + HSU_DMA_TIMEOUT_CHECK_FREQ;
443 add_timer(&chan->rx_timer);
447 static void serial_hsu_stop_rx(struct uart_port *port)
449 struct uart_hsu_port *up =
450 container_of(port, struct uart_hsu_port, port);
451 struct hsu_dma_chan *chan = up->rxc;
454 chan_writel(chan, HSU_CH_CR, 0x2);
456 up->ier &= ~UART_IER_RLSI;
457 up->port.read_status_mask &= ~UART_LSR_DR;
458 serial_out(up, UART_IER, up->ier);
462 static inline void receive_chars(struct uart_hsu_port *up, int *status)
464 struct tty_struct *tty = up->port.state->port.tty;
465 unsigned int ch, flag;
466 unsigned int max_count = 256;
472 ch = serial_in(up, UART_RX);
474 up->port.icount.rx++;
476 if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
477 UART_LSR_FE | UART_LSR_OE))) {
479 dev_warn(up->dev, "We really rush into ERR/BI case"
480 "status = 0x%02x", *status);
481 /* For statistics only */
482 if (*status & UART_LSR_BI) {
483 *status &= ~(UART_LSR_FE | UART_LSR_PE);
484 up->port.icount.brk++;
486 * We do the SysRQ and SAK checking
487 * here because otherwise the break
488 * may get masked by ignore_status_mask
489 * or read_status_mask.
491 if (uart_handle_break(&up->port))
493 } else if (*status & UART_LSR_PE)
494 up->port.icount.parity++;
495 else if (*status & UART_LSR_FE)
496 up->port.icount.frame++;
497 if (*status & UART_LSR_OE)
498 up->port.icount.overrun++;
500 /* Mask off conditions which should be ignored. */
501 *status &= up->port.read_status_mask;
503 #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
505 up->port.cons->index == up->port.line) {
506 /* Recover the break flag from console xmit */
507 *status |= up->lsr_break_flag;
508 up->lsr_break_flag = 0;
511 if (*status & UART_LSR_BI) {
513 } else if (*status & UART_LSR_PE)
515 else if (*status & UART_LSR_FE)
519 if (uart_handle_sysrq_char(&up->port, ch))
522 uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
524 *status = serial_in(up, UART_LSR);
525 } while ((*status & UART_LSR_DR) && max_count--);
526 tty_flip_buffer_push(tty);
529 static void transmit_chars(struct uart_hsu_port *up)
531 struct circ_buf *xmit = &up->port.state->xmit;
534 if (up->port.x_char) {
535 serial_out(up, UART_TX, up->port.x_char);
536 up->port.icount.tx++;
540 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
541 serial_hsu_stop_tx(&up->port);
545 #ifndef MFD_HSU_A0_STEPPING
546 count = up->port.fifosize / 2;
549 * A0 only supports fully empty IRQ, and the first char written
550 * into it won't clear the EMPT bit, so we may need be cautious
551 * by useing a shorter buffer
553 count = up->port.fifosize - 4;
556 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
557 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
559 up->port.icount.tx++;
560 if (uart_circ_empty(xmit))
562 } while (--count > 0);
564 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
565 uart_write_wakeup(&up->port);
567 if (uart_circ_empty(xmit))
568 serial_hsu_stop_tx(&up->port);
571 static inline void check_modem_status(struct uart_hsu_port *up)
575 status = serial_in(up, UART_MSR);
577 if ((status & UART_MSR_ANY_DELTA) == 0)
580 if (status & UART_MSR_TERI)
581 up->port.icount.rng++;
582 if (status & UART_MSR_DDSR)
583 up->port.icount.dsr++;
584 /* We may only get DDCD when HW init and reset */
585 if (status & UART_MSR_DDCD)
586 uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
587 /* Will start/stop_tx accordingly */
588 if (status & UART_MSR_DCTS)
589 uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
591 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
595 * This handles the interrupt from one port.
597 static irqreturn_t port_irq(int irq, void *dev_id)
599 struct uart_hsu_port *up = dev_id;
600 unsigned int iir, lsr;
603 if (unlikely(!up->running))
606 spin_lock_irqsave(&up->port.lock, flags);
608 lsr = serial_in(up, UART_LSR);
609 if (unlikely(lsr & (UART_LSR_BI | UART_LSR_PE |
610 UART_LSR_FE | UART_LSR_OE)))
612 "Got lsr irq while using DMA, lsr = 0x%2x\n",
614 check_modem_status(up);
615 spin_unlock_irqrestore(&up->port.lock, flags);
619 iir = serial_in(up, UART_IIR);
620 if (iir & UART_IIR_NO_INT) {
621 spin_unlock_irqrestore(&up->port.lock, flags);
625 lsr = serial_in(up, UART_LSR);
626 if (lsr & UART_LSR_DR)
627 receive_chars(up, &lsr);
628 check_modem_status(up);
630 /* lsr will be renewed during the receive_chars */
631 if (lsr & UART_LSR_THRE)
634 spin_unlock_irqrestore(&up->port.lock, flags);
638 static inline void dma_chan_irq(struct hsu_dma_chan *chan)
640 struct uart_hsu_port *up = chan->uport;
644 spin_lock_irqsave(&up->port.lock, flags);
646 if (!up->use_dma || !up->running)
650 * No matter what situation, need read clear the IRQ status
651 * There is a bug, see Errata 5, HSD 2900918
653 int_sts = chan_readl(chan, HSU_CH_SR);
656 if (chan->dirt == DMA_FROM_DEVICE)
657 hsu_dma_rx(up, int_sts);
660 if (chan->dirt == DMA_TO_DEVICE) {
661 chan_writel(chan, HSU_CH_CR, 0x0);
667 spin_unlock_irqrestore(&up->port.lock, flags);
671 static irqreturn_t dma_irq(int irq, void *dev_id)
673 struct hsu_port *hsu = dev_id;
676 int_sts = mfd_readl(hsu, HSU_GBL_DMAISR);
678 /* Currently we only have 6 channels may be used */
679 for (i = 0; i < 6; i++) {
681 dma_chan_irq(&hsu->chans[i]);
688 static unsigned int serial_hsu_tx_empty(struct uart_port *port)
690 struct uart_hsu_port *up =
691 container_of(port, struct uart_hsu_port, port);
695 spin_lock_irqsave(&up->port.lock, flags);
696 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
697 spin_unlock_irqrestore(&up->port.lock, flags);
702 static unsigned int serial_hsu_get_mctrl(struct uart_port *port)
704 struct uart_hsu_port *up =
705 container_of(port, struct uart_hsu_port, port);
706 unsigned char status;
709 status = serial_in(up, UART_MSR);
712 if (status & UART_MSR_DCD)
714 if (status & UART_MSR_RI)
716 if (status & UART_MSR_DSR)
718 if (status & UART_MSR_CTS)
723 static void serial_hsu_set_mctrl(struct uart_port *port, unsigned int mctrl)
725 struct uart_hsu_port *up =
726 container_of(port, struct uart_hsu_port, port);
727 unsigned char mcr = 0;
729 if (mctrl & TIOCM_RTS)
731 if (mctrl & TIOCM_DTR)
733 if (mctrl & TIOCM_OUT1)
734 mcr |= UART_MCR_OUT1;
735 if (mctrl & TIOCM_OUT2)
736 mcr |= UART_MCR_OUT2;
737 if (mctrl & TIOCM_LOOP)
738 mcr |= UART_MCR_LOOP;
742 serial_out(up, UART_MCR, mcr);
745 static void serial_hsu_break_ctl(struct uart_port *port, int break_state)
747 struct uart_hsu_port *up =
748 container_of(port, struct uart_hsu_port, port);
751 spin_lock_irqsave(&up->port.lock, flags);
752 if (break_state == -1)
753 up->lcr |= UART_LCR_SBC;
755 up->lcr &= ~UART_LCR_SBC;
756 serial_out(up, UART_LCR, up->lcr);
757 spin_unlock_irqrestore(&up->port.lock, flags);
761 * What special to do:
762 * 1. chose the 64B fifo mode
763 * 2. make sure not to select half empty mode for A0 stepping
764 * 3. start dma or pio depends on configuration
765 * 4. we only allocate dma memory when needed
767 static int serial_hsu_startup(struct uart_port *port)
769 struct uart_hsu_port *up =
770 container_of(port, struct uart_hsu_port, port);
774 * Clear the FIFO buffers and disable them.
775 * (they will be reenabled in set_termios())
777 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
778 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
779 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
780 serial_out(up, UART_FCR, 0);
782 /* Clear the interrupt registers. */
783 (void) serial_in(up, UART_LSR);
784 (void) serial_in(up, UART_RX);
785 (void) serial_in(up, UART_IIR);
786 (void) serial_in(up, UART_MSR);
788 /* Now, initialize the UART, default is 8n1 */
789 serial_out(up, UART_LCR, UART_LCR_WLEN8);
791 spin_lock_irqsave(&up->port.lock, flags);
793 up->port.mctrl |= TIOCM_OUT2;
794 serial_hsu_set_mctrl(&up->port, up->port.mctrl);
797 * Finally, enable interrupts. Note: Modem status interrupts
798 * are set via set_termios(), which will be occurring imminently
799 * anyway, so we don't enable them here.
802 up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE;
805 serial_out(up, UART_IER, up->ier);
807 spin_unlock_irqrestore(&up->port.lock, flags);
811 struct hsu_dma_buffer *dbuf;
812 struct circ_buf *xmit = &port->state->xmit;
816 /* First allocate the RX buffer */
818 dbuf->buf = kzalloc(HSU_DMA_BUF_SIZE, GFP_KERNEL);
823 dbuf->dma_addr = dma_map_single(port->dev,
827 dbuf->dma_size = HSU_DMA_BUF_SIZE;
829 /* Start the RX channel right now */
830 hsu_dma_start_rx_chan(up->rxc, dbuf);
832 /* Next init the TX DMA */
834 dbuf->buf = xmit->buf;
835 dbuf->dma_addr = dma_map_single(port->dev,
839 dbuf->dma_size = UART_XMIT_SIZE;
841 /* This should not be changed all around */
842 chan_writel(up->txc, HSU_CH_BSR, 32);
843 chan_writel(up->txc, HSU_CH_MOTSR, 4);
848 /* And clear the interrupt registers again for luck. */
849 (void) serial_in(up, UART_LSR);
850 (void) serial_in(up, UART_RX);
851 (void) serial_in(up, UART_IIR);
852 (void) serial_in(up, UART_MSR);
858 static void serial_hsu_shutdown(struct uart_port *port)
860 struct uart_hsu_port *up =
861 container_of(port, struct uart_hsu_port, port);
864 del_timer_sync(&up->rxc->rx_timer);
866 /* Disable interrupts from this port */
868 serial_out(up, UART_IER, 0);
871 spin_lock_irqsave(&up->port.lock, flags);
872 up->port.mctrl &= ~TIOCM_OUT2;
873 serial_hsu_set_mctrl(&up->port, up->port.mctrl);
874 spin_unlock_irqrestore(&up->port.lock, flags);
876 /* Disable break condition and FIFOs */
877 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
878 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
879 UART_FCR_CLEAR_RCVR |
880 UART_FCR_CLEAR_XMIT);
881 serial_out(up, UART_FCR, 0);
885 serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios,
886 struct ktermios *old)
888 struct uart_hsu_port *up =
889 container_of(port, struct uart_hsu_port, port);
890 struct tty_struct *tty = port->state->port.tty;
891 unsigned char cval, fcr = 0;
893 unsigned int baud, quot;
897 switch (termios->c_cflag & CSIZE) {
899 cval = UART_LCR_WLEN5;
902 cval = UART_LCR_WLEN6;
905 cval = UART_LCR_WLEN7;
909 cval = UART_LCR_WLEN8;
913 /* CMSPAR isn't supported by this driver */
915 tty->termios->c_cflag &= ~CMSPAR;
917 if (termios->c_cflag & CSTOPB)
918 cval |= UART_LCR_STOP;
919 if (termios->c_cflag & PARENB)
920 cval |= UART_LCR_PARITY;
921 if (!(termios->c_cflag & PARODD))
922 cval |= UART_LCR_EPAR;
925 * For those basic low baud rate we can get the direct
926 * scalar from 2746800, like 115200 = 2746800/24, for those
927 * higher baud rate, we have to handle them case by case,
928 * but DIV reg is never touched as its default value 0x3d09
930 baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
931 quot = uart_get_divisor(port, baud);
958 if ((up->port.uartclk / quot) < (2400 * 16))
959 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_1B;
960 else if ((up->port.uartclk / quot) < (230400 * 16))
961 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_16B;
963 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_32B;
965 fcr |= UART_FCR_HSU_64B_FIFO;
966 #ifdef MFD_HSU_A0_STEPPING
967 /* A0 doesn't support half empty IRQ */
968 fcr |= UART_FCR_FULL_EMPT_TXI;
972 * Ok, we're now changing the port state. Do it with
973 * interrupts disabled.
975 spin_lock_irqsave(&up->port.lock, flags);
977 /* Update the per-port timeout */
978 uart_update_timeout(port, termios->c_cflag, baud);
980 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
981 if (termios->c_iflag & INPCK)
982 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
983 if (termios->c_iflag & (BRKINT | PARMRK))
984 up->port.read_status_mask |= UART_LSR_BI;
986 /* Characters to ignore */
987 up->port.ignore_status_mask = 0;
988 if (termios->c_iflag & IGNPAR)
989 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
990 if (termios->c_iflag & IGNBRK) {
991 up->port.ignore_status_mask |= UART_LSR_BI;
993 * If we're ignoring parity and break indicators,
994 * ignore overruns too (for real raw support).
996 if (termios->c_iflag & IGNPAR)
997 up->port.ignore_status_mask |= UART_LSR_OE;
1000 /* Ignore all characters if CREAD is not set */
1001 if ((termios->c_cflag & CREAD) == 0)
1002 up->port.ignore_status_mask |= UART_LSR_DR;
1005 * CTS flow control flag and modem status interrupts, disable
1008 up->ier &= ~UART_IER_MSI;
1009 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
1010 up->ier |= UART_IER_MSI;
1012 serial_out(up, UART_IER, up->ier);
1014 if (termios->c_cflag & CRTSCTS)
1015 up->mcr |= UART_MCR_AFE | UART_MCR_RTS;
1017 up->mcr &= ~UART_MCR_AFE;
1019 serial_out(up, UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
1020 serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */
1021 serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */
1022 serial_out(up, UART_LCR, cval); /* reset DLAB */
1023 serial_out(up, UART_MUL, mul); /* set MUL */
1024 serial_out(up, UART_PS, ps); /* set PS */
1025 up->lcr = cval; /* Save LCR */
1026 serial_hsu_set_mctrl(&up->port, up->port.mctrl);
1027 serial_out(up, UART_FCR, fcr);
1028 spin_unlock_irqrestore(&up->port.lock, flags);
1032 serial_hsu_pm(struct uart_port *port, unsigned int state,
1033 unsigned int oldstate)
1037 static void serial_hsu_release_port(struct uart_port *port)
1041 static int serial_hsu_request_port(struct uart_port *port)
1046 static void serial_hsu_config_port(struct uart_port *port, int flags)
1048 struct uart_hsu_port *up =
1049 container_of(port, struct uart_hsu_port, port);
1050 up->port.type = PORT_MFD;
1054 serial_hsu_verify_port(struct uart_port *port, struct serial_struct *ser)
1056 /* We don't want the core code to modify any port params */
1061 serial_hsu_type(struct uart_port *port)
1063 struct uart_hsu_port *up =
1064 container_of(port, struct uart_hsu_port, port);
1068 /* Mainly for uart console use */
1069 static struct uart_hsu_port *serial_hsu_ports[3];
1070 static struct uart_driver serial_hsu_reg;
1072 #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
1074 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1076 /* Wait for transmitter & holding register to empty */
1077 static inline void wait_for_xmitr(struct uart_hsu_port *up)
1079 unsigned int status, tmout = 1000;
1081 /* Wait up to 1ms for the character to be sent. */
1083 status = serial_in(up, UART_LSR);
1085 if (status & UART_LSR_BI)
1086 up->lsr_break_flag = UART_LSR_BI;
1091 } while (!(status & BOTH_EMPTY));
1093 /* Wait up to 1s for flow control if necessary */
1094 if (up->port.flags & UPF_CONS_FLOW) {
1097 ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
1102 static void serial_hsu_console_putchar(struct uart_port *port, int ch)
1104 struct uart_hsu_port *up =
1105 container_of(port, struct uart_hsu_port, port);
1108 serial_out(up, UART_TX, ch);
1112 * Print a string to the serial port trying not to disturb
1113 * any possible real use of the port...
1115 * The console_lock must be held when we get here.
1118 serial_hsu_console_write(struct console *co, const char *s, unsigned int count)
1120 struct uart_hsu_port *up = serial_hsu_ports[co->index];
1121 unsigned long flags;
1125 local_irq_save(flags);
1128 else if (oops_in_progress) {
1129 locked = spin_trylock(&up->port.lock);
1131 spin_lock(&up->port.lock);
1133 /* First save the IER then disable the interrupts */
1134 ier = serial_in(up, UART_IER);
1135 serial_out(up, UART_IER, 0);
1137 uart_console_write(&up->port, s, count, serial_hsu_console_putchar);
1140 * Finally, wait for transmitter to become empty
1141 * and restore the IER
1144 serial_out(up, UART_IER, ier);
1147 spin_unlock(&up->port.lock);
1148 local_irq_restore(flags);
1151 static struct console serial_hsu_console;
1154 serial_hsu_console_setup(struct console *co, char *options)
1156 struct uart_hsu_port *up;
1163 if (co->index == -1 || co->index >= serial_hsu_reg.nr)
1165 up = serial_hsu_ports[co->index];
1170 uart_parse_options(options, &baud, &parity, &bits, &flow);
1172 ret = uart_set_options(&up->port, co, baud, parity, bits, flow);
1177 static struct console serial_hsu_console = {
1179 .write = serial_hsu_console_write,
1180 .device = uart_console_device,
1181 .setup = serial_hsu_console_setup,
1182 .flags = CON_PRINTBUFFER,
1184 .data = &serial_hsu_reg,
1188 struct uart_ops serial_hsu_pops = {
1189 .tx_empty = serial_hsu_tx_empty,
1190 .set_mctrl = serial_hsu_set_mctrl,
1191 .get_mctrl = serial_hsu_get_mctrl,
1192 .stop_tx = serial_hsu_stop_tx,
1193 .start_tx = serial_hsu_start_tx,
1194 .stop_rx = serial_hsu_stop_rx,
1195 .enable_ms = serial_hsu_enable_ms,
1196 .break_ctl = serial_hsu_break_ctl,
1197 .startup = serial_hsu_startup,
1198 .shutdown = serial_hsu_shutdown,
1199 .set_termios = serial_hsu_set_termios,
1200 .pm = serial_hsu_pm,
1201 .type = serial_hsu_type,
1202 .release_port = serial_hsu_release_port,
1203 .request_port = serial_hsu_request_port,
1204 .config_port = serial_hsu_config_port,
1205 .verify_port = serial_hsu_verify_port,
1208 static struct uart_driver serial_hsu_reg = {
1209 .owner = THIS_MODULE,
1210 .driver_name = "MFD serial",
1211 .dev_name = "ttyMFD",
1218 static int serial_hsu_suspend(struct pci_dev *pdev, pm_message_t state)
1220 void *priv = pci_get_drvdata(pdev);
1221 struct uart_hsu_port *up;
1223 /* Make sure this is not the internal dma controller */
1224 if (priv && (pdev->device != 0x081E)) {
1226 uart_suspend_port(&serial_hsu_reg, &up->port);
1229 pci_save_state(pdev);
1230 pci_set_power_state(pdev, pci_choose_state(pdev, state));
1234 static int serial_hsu_resume(struct pci_dev *pdev)
1236 void *priv = pci_get_drvdata(pdev);
1237 struct uart_hsu_port *up;
1240 pci_set_power_state(pdev, PCI_D0);
1241 pci_restore_state(pdev);
1243 ret = pci_enable_device(pdev);
1245 dev_warn(&pdev->dev,
1246 "HSU: can't re-enable device, try to continue\n");
1248 if (priv && (pdev->device != 0x081E)) {
1250 uart_resume_port(&serial_hsu_reg, &up->port);
1255 #define serial_hsu_suspend NULL
1256 #define serial_hsu_resume NULL
1259 /* temp global pointer before we settle down on using one or four PCI dev */
1260 static struct hsu_port *phsu;
1262 static int serial_hsu_probe(struct pci_dev *pdev,
1263 const struct pci_device_id *ent)
1265 struct uart_hsu_port *uport;
1268 printk(KERN_INFO "HSU: found PCI Serial controller(ID: %04x:%04x)\n",
1269 pdev->vendor, pdev->device);
1271 switch (pdev->device) {
1282 /* internal DMA controller */
1286 dev_err(&pdev->dev, "HSU: out of index!");
1290 ret = pci_enable_device(pdev);
1295 /* DMA controller */
1296 ret = request_irq(pdev->irq, dma_irq, 0, "hsu_dma", phsu);
1298 dev_err(&pdev->dev, "can not get IRQ\n");
1301 pci_set_drvdata(pdev, phsu);
1304 uport = &phsu->port[index];
1305 uport->port.irq = pdev->irq;
1306 uport->port.dev = &pdev->dev;
1307 uport->dev = &pdev->dev;
1309 ret = request_irq(pdev->irq, port_irq, 0, uport->name, uport);
1311 dev_err(&pdev->dev, "can not get IRQ\n");
1314 uart_add_one_port(&serial_hsu_reg, &uport->port);
1316 #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
1318 register_console(&serial_hsu_console);
1319 uport->port.cons = &serial_hsu_console;
1322 pci_set_drvdata(pdev, uport);
1328 pci_disable_device(pdev);
1332 static void hsu_dma_rx_timeout(unsigned long data)
1334 struct hsu_dma_chan *chan = (void *)data;
1335 struct uart_hsu_port *up = chan->uport;
1336 struct hsu_dma_buffer *dbuf = &up->rxbuf;
1338 unsigned long flags;
1340 spin_lock_irqsave(&up->port.lock, flags);
1342 count = chan_readl(chan, HSU_CH_D0SAR) - dbuf->dma_addr;
1345 mod_timer(&chan->rx_timer, jiffies + HSU_DMA_TIMEOUT_CHECK_FREQ);
1351 spin_unlock_irqrestore(&up->port.lock, flags);
1354 static void hsu_global_init(void)
1356 struct hsu_port *hsu;
1357 struct uart_hsu_port *uport;
1358 struct hsu_dma_chan *dchan;
1361 hsu = kzalloc(sizeof(struct hsu_port), GFP_KERNEL);
1365 /* Get basic io resource and map it */
1366 hsu->paddr = 0xffa28000;
1367 hsu->iolen = 0x1000;
1369 if (!(request_mem_region(hsu->paddr, hsu->iolen, "HSU global")))
1370 pr_warning("HSU: error in request mem region\n");
1372 hsu->reg = ioremap_nocache((unsigned long)hsu->paddr, hsu->iolen);
1374 pr_err("HSU: error in ioremap\n");
1376 goto err_free_region;
1379 /* Initialise the 3 UART ports */
1381 for (i = 0; i < 3; i++) {
1382 uport->port.type = PORT_MFD;
1383 uport->port.iotype = UPIO_MEM;
1384 uport->port.mapbase = (resource_size_t)hsu->paddr
1385 + HSU_PORT_REG_OFFSET
1386 + i * HSU_PORT_REG_LENGTH;
1387 uport->port.membase = hsu->reg + HSU_PORT_REG_OFFSET
1388 + i * HSU_PORT_REG_LENGTH;
1390 sprintf(uport->name, "hsu_port%d", i);
1391 uport->port.fifosize = 64;
1392 uport->port.ops = &serial_hsu_pops;
1393 uport->port.line = i;
1394 uport->port.flags = UPF_IOREMAP;
1395 /* set the scalable maxim support rate to 2746800 bps */
1396 uport->port.uartclk = 115200 * 24 * 16;
1399 uport->txc = &hsu->chans[i * 2];
1400 uport->rxc = &hsu->chans[i * 2 + 1];
1402 serial_hsu_ports[i] = uport;
1407 /* Initialise 6 dma channels */
1409 for (i = 0; i < 6; i++) {
1411 dchan->dirt = (i & 0x1) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1412 dchan->uport = &hsu->port[i/2];
1413 dchan->reg = hsu->reg + HSU_DMA_CHANS_REG_OFFSET +
1414 i * HSU_DMA_CHANS_REG_LENGTH;
1416 /* Work around for RX */
1417 if (dchan->dirt == DMA_FROM_DEVICE) {
1418 init_timer(&dchan->rx_timer);
1419 dchan->rx_timer.function = hsu_dma_rx_timeout;
1420 dchan->rx_timer.data = (unsigned long)dchan;
1427 hsu_debugfs_init(hsu);
1431 release_mem_region(hsu->paddr, hsu->iolen);
1436 static void serial_hsu_remove(struct pci_dev *pdev)
1438 struct hsu_port *hsu;
1441 hsu = pci_get_drvdata(pdev);
1445 for (i = 0; i < 3; i++)
1446 uart_remove_one_port(&serial_hsu_reg, &hsu->port[i].port);
1448 pci_set_drvdata(pdev, NULL);
1449 free_irq(hsu->irq, hsu);
1450 pci_disable_device(pdev);
1453 /* First 3 are UART ports, and the 4th is the DMA */
1454 static const struct pci_device_id pci_ids[] __devinitdata = {
1455 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081B) },
1456 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081C) },
1457 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081D) },
1458 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081E) },
1462 static struct pci_driver hsu_pci_driver = {
1463 .name = "HSU serial",
1464 .id_table = pci_ids,
1465 .probe = serial_hsu_probe,
1466 .remove = __devexit_p(serial_hsu_remove),
1467 .suspend = serial_hsu_suspend,
1468 .resume = serial_hsu_resume,
1471 static int __init hsu_pci_init(void)
1477 ret = uart_register_driver(&serial_hsu_reg);
1481 return pci_register_driver(&hsu_pci_driver);
1484 static void __exit hsu_pci_exit(void)
1486 pci_unregister_driver(&hsu_pci_driver);
1487 uart_unregister_driver(&serial_hsu_reg);
1489 hsu_debugfs_remove(phsu);
1494 module_init(hsu_pci_init);
1495 module_exit(hsu_pci_exit);
1497 MODULE_LICENSE("GPL v2");
1498 MODULE_ALIAS("platform:medfield-hsu");