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/slab.h>
31 #include <linux/serial_reg.h>
32 #include <linux/circ_buf.h>
33 #include <linux/delay.h>
34 #include <linux/interrupt.h>
35 #include <linux/tty.h>
36 #include <linux/tty_flip.h>
37 #include <linux/serial_core.h>
38 #include <linux/serial_mfd.h>
39 #include <linux/dma-mapping.h>
40 #include <linux/pci.h>
42 #include <linux/debugfs.h>
44 #define MFD_HSU_A0_STEPPING 1
46 #define HSU_DMA_BUF_SIZE 2048
48 #define chan_readl(chan, offset) readl(chan->reg + offset)
49 #define chan_writel(chan, offset, val) writel(val, chan->reg + offset)
51 #define mfd_readl(obj, offset) readl(obj->reg + offset)
52 #define mfd_writel(obj, offset, val) writel(val, obj->reg + offset)
54 #define HSU_DMA_TIMEOUT_CHECK_FREQ (HZ/10)
56 struct hsu_dma_buffer
{
65 enum dma_data_direction dirt
;
66 struct uart_hsu_port
*uport
;
68 struct timer_list rx_timer
; /* only needed by RX channel */
71 struct uart_hsu_port
{
72 struct uart_port port
;
76 unsigned int lsr_break_flag
;
81 struct hsu_dma_chan
*txc
;
82 struct hsu_dma_chan
*rxc
;
83 struct hsu_dma_buffer txbuf
;
84 struct hsu_dma_buffer rxbuf
;
85 int use_dma
; /* flag for DMA/PIO */
90 /* Top level data structure of HSU */
97 struct uart_hsu_port port
[3];
98 struct hsu_dma_chan chans
[10];
100 struct dentry
*debugfs
;
103 static inline unsigned int serial_in(struct uart_hsu_port
*up
, int offset
)
107 if (offset
> UART_MSR
) {
109 val
= readl(up
->port
.membase
+ offset
);
111 val
= (unsigned int)readb(up
->port
.membase
+ offset
);
116 static inline void serial_out(struct uart_hsu_port
*up
, int offset
, int value
)
118 if (offset
> UART_MSR
) {
120 writel(value
, up
->port
.membase
+ offset
);
122 unsigned char val
= value
& 0xff;
123 writeb(val
, up
->port
.membase
+ offset
);
127 #ifdef CONFIG_DEBUG_FS
129 #define HSU_REGS_BUFSIZE 1024
131 static int hsu_show_regs_open(struct inode
*inode
, struct file
*file
)
133 file
->private_data
= inode
->i_private
;
137 static ssize_t
port_show_regs(struct file
*file
, char __user
*user_buf
,
138 size_t count
, loff_t
*ppos
)
140 struct uart_hsu_port
*up
= file
->private_data
;
145 buf
= kzalloc(HSU_REGS_BUFSIZE
, GFP_KERNEL
);
149 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
150 "MFD HSU port[%d] regs:\n", up
->index
);
152 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
153 "=================================\n");
154 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
155 "IER: \t\t0x%08x\n", serial_in(up
, UART_IER
));
156 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
157 "IIR: \t\t0x%08x\n", serial_in(up
, UART_IIR
));
158 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
159 "LCR: \t\t0x%08x\n", serial_in(up
, UART_LCR
));
160 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
161 "MCR: \t\t0x%08x\n", serial_in(up
, UART_MCR
));
162 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
163 "LSR: \t\t0x%08x\n", serial_in(up
, UART_LSR
));
164 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
165 "MSR: \t\t0x%08x\n", serial_in(up
, UART_MSR
));
166 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
167 "FOR: \t\t0x%08x\n", serial_in(up
, UART_FOR
));
168 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
169 "PS: \t\t0x%08x\n", serial_in(up
, UART_PS
));
170 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
171 "MUL: \t\t0x%08x\n", serial_in(up
, UART_MUL
));
172 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
173 "DIV: \t\t0x%08x\n", serial_in(up
, UART_DIV
));
175 if (len
> HSU_REGS_BUFSIZE
)
176 len
= HSU_REGS_BUFSIZE
;
178 ret
= simple_read_from_buffer(user_buf
, count
, ppos
, buf
, len
);
183 static ssize_t
dma_show_regs(struct file
*file
, char __user
*user_buf
,
184 size_t count
, loff_t
*ppos
)
186 struct hsu_dma_chan
*chan
= file
->private_data
;
191 buf
= kzalloc(HSU_REGS_BUFSIZE
, GFP_KERNEL
);
195 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
196 "MFD HSU DMA channel [%d] regs:\n", chan
->id
);
198 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
199 "=================================\n");
200 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
201 "CR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_CR
));
202 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
203 "DCR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_DCR
));
204 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
205 "BSR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_BSR
));
206 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
207 "MOTSR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_MOTSR
));
208 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
209 "D0SAR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_D0SAR
));
210 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
211 "D0TSR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_D0TSR
));
212 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
213 "D0SAR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_D1SAR
));
214 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
215 "D0TSR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_D1TSR
));
216 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
217 "D0SAR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_D2SAR
));
218 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
219 "D0TSR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_D2TSR
));
220 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
221 "D0SAR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_D3SAR
));
222 len
+= snprintf(buf
+ len
, HSU_REGS_BUFSIZE
- len
,
223 "D0TSR: \t\t0x%08x\n", chan_readl(chan
, HSU_CH_D3TSR
));
225 if (len
> HSU_REGS_BUFSIZE
)
226 len
= HSU_REGS_BUFSIZE
;
228 ret
= simple_read_from_buffer(user_buf
, count
, ppos
, buf
, len
);
233 static const struct file_operations port_regs_ops
= {
234 .owner
= THIS_MODULE
,
235 .open
= hsu_show_regs_open
,
236 .read
= port_show_regs
,
237 .llseek
= default_llseek
,
240 static const struct file_operations dma_regs_ops
= {
241 .owner
= THIS_MODULE
,
242 .open
= hsu_show_regs_open
,
243 .read
= dma_show_regs
,
244 .llseek
= default_llseek
,
247 static int hsu_debugfs_init(struct hsu_port
*hsu
)
252 hsu
->debugfs
= debugfs_create_dir("hsu", NULL
);
256 for (i
= 0; i
< 3; i
++) {
257 snprintf(name
, sizeof(name
), "port_%d_regs", i
);
258 debugfs_create_file(name
, S_IFREG
| S_IRUGO
,
259 hsu
->debugfs
, (void *)(&hsu
->port
[i
]), &port_regs_ops
);
262 for (i
= 0; i
< 6; i
++) {
263 snprintf(name
, sizeof(name
), "dma_chan_%d_regs", i
);
264 debugfs_create_file(name
, S_IFREG
| S_IRUGO
,
265 hsu
->debugfs
, (void *)&hsu
->chans
[i
], &dma_regs_ops
);
271 static void hsu_debugfs_remove(struct hsu_port
*hsu
)
274 debugfs_remove_recursive(hsu
->debugfs
);
278 static inline int hsu_debugfs_init(struct hsu_port
*hsu
)
283 static inline void hsu_debugfs_remove(struct hsu_port
*hsu
)
286 #endif /* CONFIG_DEBUG_FS */
288 static void serial_hsu_enable_ms(struct uart_port
*port
)
290 struct uart_hsu_port
*up
=
291 container_of(port
, struct uart_hsu_port
, port
);
293 up
->ier
|= UART_IER_MSI
;
294 serial_out(up
, UART_IER
, up
->ier
);
297 void hsu_dma_tx(struct uart_hsu_port
*up
)
299 struct circ_buf
*xmit
= &up
->port
.state
->xmit
;
300 struct hsu_dma_buffer
*dbuf
= &up
->txbuf
;
303 /* test_and_set_bit may be better, but anyway it's in lock protected mode */
307 /* Update the circ buf info */
308 xmit
->tail
+= dbuf
->ofs
;
309 xmit
->tail
&= UART_XMIT_SIZE
- 1;
311 up
->port
.icount
.tx
+= dbuf
->ofs
;
314 /* Disable the channel */
315 chan_writel(up
->txc
, HSU_CH_CR
, 0x0);
317 if (!uart_circ_empty(xmit
) && !uart_tx_stopped(&up
->port
)) {
318 dma_sync_single_for_device(up
->port
.dev
,
323 count
= CIRC_CNT_TO_END(xmit
->head
, xmit
->tail
, UART_XMIT_SIZE
);
326 /* Reprogram the channel */
327 chan_writel(up
->txc
, HSU_CH_D0SAR
, dbuf
->dma_addr
+ xmit
->tail
);
328 chan_writel(up
->txc
, HSU_CH_D0TSR
, count
);
330 /* Reenable the channel */
331 chan_writel(up
->txc
, HSU_CH_DCR
, 0x1
336 chan_writel(up
->txc
, HSU_CH_CR
, 0x1);
339 if (uart_circ_chars_pending(xmit
) < WAKEUP_CHARS
)
340 uart_write_wakeup(&up
->port
);
343 /* The buffer is already cache coherent */
344 void hsu_dma_start_rx_chan(struct hsu_dma_chan
*rxc
, struct hsu_dma_buffer
*dbuf
)
348 chan_writel(rxc
, HSU_CH_BSR
, 32);
349 chan_writel(rxc
, HSU_CH_MOTSR
, 4);
351 chan_writel(rxc
, HSU_CH_D0SAR
, dbuf
->dma_addr
);
352 chan_writel(rxc
, HSU_CH_D0TSR
, dbuf
->dma_size
);
353 chan_writel(rxc
, HSU_CH_DCR
, 0x1 | (0x1 << 8)
355 | (0x1 << 24) /* timeout bit, see HSU Errata 1 */
357 chan_writel(rxc
, HSU_CH_CR
, 0x3);
359 mod_timer(&rxc
->rx_timer
, jiffies
+ HSU_DMA_TIMEOUT_CHECK_FREQ
);
362 /* Protected by spin_lock_irqsave(port->lock) */
363 static void serial_hsu_start_tx(struct uart_port
*port
)
365 struct uart_hsu_port
*up
=
366 container_of(port
, struct uart_hsu_port
, port
);
370 } else if (!(up
->ier
& UART_IER_THRI
)) {
371 up
->ier
|= UART_IER_THRI
;
372 serial_out(up
, UART_IER
, up
->ier
);
376 static void serial_hsu_stop_tx(struct uart_port
*port
)
378 struct uart_hsu_port
*up
=
379 container_of(port
, struct uart_hsu_port
, port
);
380 struct hsu_dma_chan
*txc
= up
->txc
;
383 chan_writel(txc
, HSU_CH_CR
, 0x0);
384 else if (up
->ier
& UART_IER_THRI
) {
385 up
->ier
&= ~UART_IER_THRI
;
386 serial_out(up
, UART_IER
, up
->ier
);
390 /* This is always called in spinlock protected mode, so
391 * modify timeout timer is safe here */
392 void hsu_dma_rx(struct uart_hsu_port
*up
, u32 int_sts
)
394 struct hsu_dma_buffer
*dbuf
= &up
->rxbuf
;
395 struct hsu_dma_chan
*chan
= up
->rxc
;
396 struct uart_port
*port
= &up
->port
;
397 struct tty_struct
*tty
= port
->state
->port
.tty
;
404 * First need to know how many is already transferred,
405 * then check if its a timeout DMA irq, and return
406 * the trail bytes out, push them up and reenable the
410 /* Timeout IRQ, need wait some time, see Errata 2 */
414 /* Stop the channel */
415 chan_writel(chan
, HSU_CH_CR
, 0x0);
417 count
= chan_readl(chan
, HSU_CH_D0SAR
) - dbuf
->dma_addr
;
419 /* Restart the channel before we leave */
420 chan_writel(chan
, HSU_CH_CR
, 0x3);
423 del_timer(&chan
->rx_timer
);
425 dma_sync_single_for_cpu(port
->dev
, dbuf
->dma_addr
,
426 dbuf
->dma_size
, DMA_FROM_DEVICE
);
429 * Head will only wrap around when we recycle
430 * the DMA buffer, and when that happens, we
431 * explicitly set tail to 0. So head will
432 * always be greater than tail.
434 tty_insert_flip_string(tty
, dbuf
->buf
, count
);
435 port
->icount
.rx
+= count
;
437 dma_sync_single_for_device(up
->port
.dev
, dbuf
->dma_addr
,
438 dbuf
->dma_size
, DMA_FROM_DEVICE
);
440 /* Reprogram the channel */
441 chan_writel(chan
, HSU_CH_D0SAR
, dbuf
->dma_addr
);
442 chan_writel(chan
, HSU_CH_D0TSR
, dbuf
->dma_size
);
443 chan_writel(chan
, HSU_CH_DCR
, 0x1
446 | (0x1 << 24) /* timeout bit, see HSU Errata 1 */
448 tty_flip_buffer_push(tty
);
450 chan_writel(chan
, HSU_CH_CR
, 0x3);
451 chan
->rx_timer
.expires
= jiffies
+ HSU_DMA_TIMEOUT_CHECK_FREQ
;
452 add_timer(&chan
->rx_timer
);
456 static void serial_hsu_stop_rx(struct uart_port
*port
)
458 struct uart_hsu_port
*up
=
459 container_of(port
, struct uart_hsu_port
, port
);
460 struct hsu_dma_chan
*chan
= up
->rxc
;
463 chan_writel(chan
, HSU_CH_CR
, 0x2);
465 up
->ier
&= ~UART_IER_RLSI
;
466 up
->port
.read_status_mask
&= ~UART_LSR_DR
;
467 serial_out(up
, UART_IER
, up
->ier
);
471 static inline void receive_chars(struct uart_hsu_port
*up
, int *status
)
473 struct tty_struct
*tty
= up
->port
.state
->port
.tty
;
474 unsigned int ch
, flag
;
475 unsigned int max_count
= 256;
481 ch
= serial_in(up
, UART_RX
);
483 up
->port
.icount
.rx
++;
485 if (unlikely(*status
& (UART_LSR_BI
| UART_LSR_PE
|
486 UART_LSR_FE
| UART_LSR_OE
))) {
488 dev_warn(up
->dev
, "We really rush into ERR/BI case"
489 "status = 0x%02x", *status
);
490 /* For statistics only */
491 if (*status
& UART_LSR_BI
) {
492 *status
&= ~(UART_LSR_FE
| UART_LSR_PE
);
493 up
->port
.icount
.brk
++;
495 * We do the SysRQ and SAK checking
496 * here because otherwise the break
497 * may get masked by ignore_status_mask
498 * or read_status_mask.
500 if (uart_handle_break(&up
->port
))
502 } else if (*status
& UART_LSR_PE
)
503 up
->port
.icount
.parity
++;
504 else if (*status
& UART_LSR_FE
)
505 up
->port
.icount
.frame
++;
506 if (*status
& UART_LSR_OE
)
507 up
->port
.icount
.overrun
++;
509 /* Mask off conditions which should be ignored. */
510 *status
&= up
->port
.read_status_mask
;
512 #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
514 up
->port
.cons
->index
== up
->port
.line
) {
515 /* Recover the break flag from console xmit */
516 *status
|= up
->lsr_break_flag
;
517 up
->lsr_break_flag
= 0;
520 if (*status
& UART_LSR_BI
) {
522 } else if (*status
& UART_LSR_PE
)
524 else if (*status
& UART_LSR_FE
)
528 if (uart_handle_sysrq_char(&up
->port
, ch
))
531 uart_insert_char(&up
->port
, *status
, UART_LSR_OE
, ch
, flag
);
533 *status
= serial_in(up
, UART_LSR
);
534 } while ((*status
& UART_LSR_DR
) && max_count
--);
535 tty_flip_buffer_push(tty
);
538 static void transmit_chars(struct uart_hsu_port
*up
)
540 struct circ_buf
*xmit
= &up
->port
.state
->xmit
;
543 if (up
->port
.x_char
) {
544 serial_out(up
, UART_TX
, up
->port
.x_char
);
545 up
->port
.icount
.tx
++;
549 if (uart_circ_empty(xmit
) || uart_tx_stopped(&up
->port
)) {
550 serial_hsu_stop_tx(&up
->port
);
554 #ifndef MFD_HSU_A0_STEPPING
555 count
= up
->port
.fifosize
/ 2;
558 * A0 only supports fully empty IRQ, and the first char written
559 * into it won't clear the EMPT bit, so we may need be cautious
560 * by useing a shorter buffer
562 count
= up
->port
.fifosize
- 4;
565 serial_out(up
, UART_TX
, xmit
->buf
[xmit
->tail
]);
566 xmit
->tail
= (xmit
->tail
+ 1) & (UART_XMIT_SIZE
- 1);
568 up
->port
.icount
.tx
++;
569 if (uart_circ_empty(xmit
))
571 } while (--count
> 0);
573 if (uart_circ_chars_pending(xmit
) < WAKEUP_CHARS
)
574 uart_write_wakeup(&up
->port
);
576 if (uart_circ_empty(xmit
))
577 serial_hsu_stop_tx(&up
->port
);
580 static inline void check_modem_status(struct uart_hsu_port
*up
)
584 status
= serial_in(up
, UART_MSR
);
586 if ((status
& UART_MSR_ANY_DELTA
) == 0)
589 if (status
& UART_MSR_TERI
)
590 up
->port
.icount
.rng
++;
591 if (status
& UART_MSR_DDSR
)
592 up
->port
.icount
.dsr
++;
593 /* We may only get DDCD when HW init and reset */
594 if (status
& UART_MSR_DDCD
)
595 uart_handle_dcd_change(&up
->port
, status
& UART_MSR_DCD
);
596 /* Will start/stop_tx accordingly */
597 if (status
& UART_MSR_DCTS
)
598 uart_handle_cts_change(&up
->port
, status
& UART_MSR_CTS
);
600 wake_up_interruptible(&up
->port
.state
->port
.delta_msr_wait
);
604 * This handles the interrupt from one port.
606 static irqreturn_t
port_irq(int irq
, void *dev_id
)
608 struct uart_hsu_port
*up
= dev_id
;
609 unsigned int iir
, lsr
;
612 if (unlikely(!up
->running
))
615 spin_lock_irqsave(&up
->port
.lock
, flags
);
617 lsr
= serial_in(up
, UART_LSR
);
618 if (unlikely(lsr
& (UART_LSR_BI
| UART_LSR_PE
|
619 UART_LSR_FE
| UART_LSR_OE
)))
621 "Got lsr irq while using DMA, lsr = 0x%2x\n",
623 check_modem_status(up
);
624 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
628 iir
= serial_in(up
, UART_IIR
);
629 if (iir
& UART_IIR_NO_INT
) {
630 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
634 lsr
= serial_in(up
, UART_LSR
);
635 if (lsr
& UART_LSR_DR
)
636 receive_chars(up
, &lsr
);
637 check_modem_status(up
);
639 /* lsr will be renewed during the receive_chars */
640 if (lsr
& UART_LSR_THRE
)
643 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
647 static inline void dma_chan_irq(struct hsu_dma_chan
*chan
)
649 struct uart_hsu_port
*up
= chan
->uport
;
653 spin_lock_irqsave(&up
->port
.lock
, flags
);
655 if (!up
->use_dma
|| !up
->running
)
659 * No matter what situation, need read clear the IRQ status
660 * There is a bug, see Errata 5, HSD 2900918
662 int_sts
= chan_readl(chan
, HSU_CH_SR
);
665 if (chan
->dirt
== DMA_FROM_DEVICE
)
666 hsu_dma_rx(up
, int_sts
);
669 if (chan
->dirt
== DMA_TO_DEVICE
) {
670 chan_writel(chan
, HSU_CH_CR
, 0x0);
676 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
680 static irqreturn_t
dma_irq(int irq
, void *dev_id
)
682 struct hsu_port
*hsu
= dev_id
;
685 int_sts
= mfd_readl(hsu
, HSU_GBL_DMAISR
);
687 /* Currently we only have 6 channels may be used */
688 for (i
= 0; i
< 6; i
++) {
690 dma_chan_irq(&hsu
->chans
[i
]);
697 static unsigned int serial_hsu_tx_empty(struct uart_port
*port
)
699 struct uart_hsu_port
*up
=
700 container_of(port
, struct uart_hsu_port
, port
);
704 spin_lock_irqsave(&up
->port
.lock
, flags
);
705 ret
= serial_in(up
, UART_LSR
) & UART_LSR_TEMT
? TIOCSER_TEMT
: 0;
706 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
711 static unsigned int serial_hsu_get_mctrl(struct uart_port
*port
)
713 struct uart_hsu_port
*up
=
714 container_of(port
, struct uart_hsu_port
, port
);
715 unsigned char status
;
718 status
= serial_in(up
, UART_MSR
);
721 if (status
& UART_MSR_DCD
)
723 if (status
& UART_MSR_RI
)
725 if (status
& UART_MSR_DSR
)
727 if (status
& UART_MSR_CTS
)
732 static void serial_hsu_set_mctrl(struct uart_port
*port
, unsigned int mctrl
)
734 struct uart_hsu_port
*up
=
735 container_of(port
, struct uart_hsu_port
, port
);
736 unsigned char mcr
= 0;
738 if (mctrl
& TIOCM_RTS
)
740 if (mctrl
& TIOCM_DTR
)
742 if (mctrl
& TIOCM_OUT1
)
743 mcr
|= UART_MCR_OUT1
;
744 if (mctrl
& TIOCM_OUT2
)
745 mcr
|= UART_MCR_OUT2
;
746 if (mctrl
& TIOCM_LOOP
)
747 mcr
|= UART_MCR_LOOP
;
751 serial_out(up
, UART_MCR
, mcr
);
754 static void serial_hsu_break_ctl(struct uart_port
*port
, int break_state
)
756 struct uart_hsu_port
*up
=
757 container_of(port
, struct uart_hsu_port
, port
);
760 spin_lock_irqsave(&up
->port
.lock
, flags
);
761 if (break_state
== -1)
762 up
->lcr
|= UART_LCR_SBC
;
764 up
->lcr
&= ~UART_LCR_SBC
;
765 serial_out(up
, UART_LCR
, up
->lcr
);
766 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
770 * What special to do:
771 * 1. chose the 64B fifo mode
772 * 2. make sure not to select half empty mode for A0 stepping
773 * 3. start dma or pio depends on configuration
774 * 4. we only allocate dma memory when needed
776 static int serial_hsu_startup(struct uart_port
*port
)
778 struct uart_hsu_port
*up
=
779 container_of(port
, struct uart_hsu_port
, port
);
783 * Clear the FIFO buffers and disable them.
784 * (they will be reenabled in set_termios())
786 serial_out(up
, UART_FCR
, UART_FCR_ENABLE_FIFO
);
787 serial_out(up
, UART_FCR
, UART_FCR_ENABLE_FIFO
|
788 UART_FCR_CLEAR_RCVR
| UART_FCR_CLEAR_XMIT
);
789 serial_out(up
, UART_FCR
, 0);
791 /* Clear the interrupt registers. */
792 (void) serial_in(up
, UART_LSR
);
793 (void) serial_in(up
, UART_RX
);
794 (void) serial_in(up
, UART_IIR
);
795 (void) serial_in(up
, UART_MSR
);
797 /* Now, initialize the UART, default is 8n1 */
798 serial_out(up
, UART_LCR
, UART_LCR_WLEN8
);
800 spin_lock_irqsave(&up
->port
.lock
, flags
);
802 up
->port
.mctrl
|= TIOCM_OUT2
;
803 serial_hsu_set_mctrl(&up
->port
, up
->port
.mctrl
);
806 * Finally, enable interrupts. Note: Modem status interrupts
807 * are set via set_termios(), which will be occurring imminently
808 * anyway, so we don't enable them here.
811 up
->ier
= UART_IER_RLSI
| UART_IER_RDI
| UART_IER_RTOIE
;
814 serial_out(up
, UART_IER
, up
->ier
);
816 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
820 struct hsu_dma_buffer
*dbuf
;
821 struct circ_buf
*xmit
= &port
->state
->xmit
;
825 /* First allocate the RX buffer */
827 dbuf
->buf
= kzalloc(HSU_DMA_BUF_SIZE
, GFP_KERNEL
);
832 dbuf
->dma_addr
= dma_map_single(port
->dev
,
836 dbuf
->dma_size
= HSU_DMA_BUF_SIZE
;
838 /* Start the RX channel right now */
839 hsu_dma_start_rx_chan(up
->rxc
, dbuf
);
841 /* Next init the TX DMA */
843 dbuf
->buf
= xmit
->buf
;
844 dbuf
->dma_addr
= dma_map_single(port
->dev
,
848 dbuf
->dma_size
= UART_XMIT_SIZE
;
850 /* This should not be changed all around */
851 chan_writel(up
->txc
, HSU_CH_BSR
, 32);
852 chan_writel(up
->txc
, HSU_CH_MOTSR
, 4);
857 /* And clear the interrupt registers again for luck. */
858 (void) serial_in(up
, UART_LSR
);
859 (void) serial_in(up
, UART_RX
);
860 (void) serial_in(up
, UART_IIR
);
861 (void) serial_in(up
, UART_MSR
);
867 static void serial_hsu_shutdown(struct uart_port
*port
)
869 struct uart_hsu_port
*up
=
870 container_of(port
, struct uart_hsu_port
, port
);
873 del_timer_sync(&up
->rxc
->rx_timer
);
875 /* Disable interrupts from this port */
877 serial_out(up
, UART_IER
, 0);
880 spin_lock_irqsave(&up
->port
.lock
, flags
);
881 up
->port
.mctrl
&= ~TIOCM_OUT2
;
882 serial_hsu_set_mctrl(&up
->port
, up
->port
.mctrl
);
883 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
885 /* Disable break condition and FIFOs */
886 serial_out(up
, UART_LCR
, serial_in(up
, UART_LCR
) & ~UART_LCR_SBC
);
887 serial_out(up
, UART_FCR
, UART_FCR_ENABLE_FIFO
|
888 UART_FCR_CLEAR_RCVR
|
889 UART_FCR_CLEAR_XMIT
);
890 serial_out(up
, UART_FCR
, 0);
894 serial_hsu_set_termios(struct uart_port
*port
, struct ktermios
*termios
,
895 struct ktermios
*old
)
897 struct uart_hsu_port
*up
=
898 container_of(port
, struct uart_hsu_port
, port
);
899 struct tty_struct
*tty
= port
->state
->port
.tty
;
900 unsigned char cval
, fcr
= 0;
902 unsigned int baud
, quot
;
905 switch (termios
->c_cflag
& CSIZE
) {
907 cval
= UART_LCR_WLEN5
;
910 cval
= UART_LCR_WLEN6
;
913 cval
= UART_LCR_WLEN7
;
917 cval
= UART_LCR_WLEN8
;
921 /* CMSPAR isn't supported by this driver */
923 tty
->termios
->c_cflag
&= ~CMSPAR
;
925 if (termios
->c_cflag
& CSTOPB
)
926 cval
|= UART_LCR_STOP
;
927 if (termios
->c_cflag
& PARENB
)
928 cval
|= UART_LCR_PARITY
;
929 if (!(termios
->c_cflag
& PARODD
))
930 cval
|= UART_LCR_EPAR
;
933 * The base clk is 50Mhz, and the baud rate come from:
934 * baud = 50M * MUL / (DIV * PS * DLAB)
936 * For those basic low baud rate we can get the direct
937 * scalar from 2746800, like 115200 = 2746800/24. For those
938 * higher baud rate, we handle them case by case, mainly by
939 * adjusting the MUL/PS registers, and DIV register is kept
940 * as default value 0x3d09 to make things simple
942 baud
= uart_get_baud_rate(port
, termios
, old
, 0, 4000000);
961 /* mul/ps/quot = 0x9C4/0x10/0x1 will make a 500000 bps */
962 mul
= baud
/ 500000 * 0x9C4;
965 /* Use uart_get_divisor to get quot for other baud rates */
970 quot
= uart_get_divisor(port
, baud
);
972 if ((up
->port
.uartclk
/ quot
) < (2400 * 16))
973 fcr
= UART_FCR_ENABLE_FIFO
| UART_FCR_HSU_64_1B
;
974 else if ((up
->port
.uartclk
/ quot
) < (230400 * 16))
975 fcr
= UART_FCR_ENABLE_FIFO
| UART_FCR_HSU_64_16B
;
977 fcr
= UART_FCR_ENABLE_FIFO
| UART_FCR_HSU_64_32B
;
979 fcr
|= UART_FCR_HSU_64B_FIFO
;
980 #ifdef MFD_HSU_A0_STEPPING
981 /* A0 doesn't support half empty IRQ */
982 fcr
|= UART_FCR_FULL_EMPT_TXI
;
986 * Ok, we're now changing the port state. Do it with
987 * interrupts disabled.
989 spin_lock_irqsave(&up
->port
.lock
, flags
);
991 /* Update the per-port timeout */
992 uart_update_timeout(port
, termios
->c_cflag
, baud
);
994 up
->port
.read_status_mask
= UART_LSR_OE
| UART_LSR_THRE
| UART_LSR_DR
;
995 if (termios
->c_iflag
& INPCK
)
996 up
->port
.read_status_mask
|= UART_LSR_FE
| UART_LSR_PE
;
997 if (termios
->c_iflag
& (BRKINT
| PARMRK
))
998 up
->port
.read_status_mask
|= UART_LSR_BI
;
1000 /* Characters to ignore */
1001 up
->port
.ignore_status_mask
= 0;
1002 if (termios
->c_iflag
& IGNPAR
)
1003 up
->port
.ignore_status_mask
|= UART_LSR_PE
| UART_LSR_FE
;
1004 if (termios
->c_iflag
& IGNBRK
) {
1005 up
->port
.ignore_status_mask
|= UART_LSR_BI
;
1007 * If we're ignoring parity and break indicators,
1008 * ignore overruns too (for real raw support).
1010 if (termios
->c_iflag
& IGNPAR
)
1011 up
->port
.ignore_status_mask
|= UART_LSR_OE
;
1014 /* Ignore all characters if CREAD is not set */
1015 if ((termios
->c_cflag
& CREAD
) == 0)
1016 up
->port
.ignore_status_mask
|= UART_LSR_DR
;
1019 * CTS flow control flag and modem status interrupts, disable
1022 up
->ier
&= ~UART_IER_MSI
;
1023 if (UART_ENABLE_MS(&up
->port
, termios
->c_cflag
))
1024 up
->ier
|= UART_IER_MSI
;
1026 serial_out(up
, UART_IER
, up
->ier
);
1028 if (termios
->c_cflag
& CRTSCTS
)
1029 up
->mcr
|= UART_MCR_AFE
| UART_MCR_RTS
;
1031 up
->mcr
&= ~UART_MCR_AFE
;
1033 serial_out(up
, UART_LCR
, cval
| UART_LCR_DLAB
); /* set DLAB */
1034 serial_out(up
, UART_DLL
, quot
& 0xff); /* LS of divisor */
1035 serial_out(up
, UART_DLM
, quot
>> 8); /* MS of divisor */
1036 serial_out(up
, UART_LCR
, cval
); /* reset DLAB */
1037 serial_out(up
, UART_MUL
, mul
); /* set MUL */
1038 serial_out(up
, UART_PS
, ps
); /* set PS */
1039 up
->lcr
= cval
; /* Save LCR */
1040 serial_hsu_set_mctrl(&up
->port
, up
->port
.mctrl
);
1041 serial_out(up
, UART_FCR
, fcr
);
1042 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
1046 serial_hsu_pm(struct uart_port
*port
, unsigned int state
,
1047 unsigned int oldstate
)
1051 static void serial_hsu_release_port(struct uart_port
*port
)
1055 static int serial_hsu_request_port(struct uart_port
*port
)
1060 static void serial_hsu_config_port(struct uart_port
*port
, int flags
)
1062 struct uart_hsu_port
*up
=
1063 container_of(port
, struct uart_hsu_port
, port
);
1064 up
->port
.type
= PORT_MFD
;
1068 serial_hsu_verify_port(struct uart_port
*port
, struct serial_struct
*ser
)
1070 /* We don't want the core code to modify any port params */
1075 serial_hsu_type(struct uart_port
*port
)
1077 struct uart_hsu_port
*up
=
1078 container_of(port
, struct uart_hsu_port
, port
);
1082 /* Mainly for uart console use */
1083 static struct uart_hsu_port
*serial_hsu_ports
[3];
1084 static struct uart_driver serial_hsu_reg
;
1086 #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
1088 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1090 /* Wait for transmitter & holding register to empty */
1091 static inline void wait_for_xmitr(struct uart_hsu_port
*up
)
1093 unsigned int status
, tmout
= 1000;
1095 /* Wait up to 1ms for the character to be sent. */
1097 status
= serial_in(up
, UART_LSR
);
1099 if (status
& UART_LSR_BI
)
1100 up
->lsr_break_flag
= UART_LSR_BI
;
1105 } while (!(status
& BOTH_EMPTY
));
1107 /* Wait up to 1s for flow control if necessary */
1108 if (up
->port
.flags
& UPF_CONS_FLOW
) {
1111 ((serial_in(up
, UART_MSR
) & UART_MSR_CTS
) == 0))
1116 static void serial_hsu_console_putchar(struct uart_port
*port
, int ch
)
1118 struct uart_hsu_port
*up
=
1119 container_of(port
, struct uart_hsu_port
, port
);
1122 serial_out(up
, UART_TX
, ch
);
1126 * Print a string to the serial port trying not to disturb
1127 * any possible real use of the port...
1129 * The console_lock must be held when we get here.
1132 serial_hsu_console_write(struct console
*co
, const char *s
, unsigned int count
)
1134 struct uart_hsu_port
*up
= serial_hsu_ports
[co
->index
];
1135 unsigned long flags
;
1139 local_irq_save(flags
);
1142 else if (oops_in_progress
) {
1143 locked
= spin_trylock(&up
->port
.lock
);
1145 spin_lock(&up
->port
.lock
);
1147 /* First save the IER then disable the interrupts */
1148 ier
= serial_in(up
, UART_IER
);
1149 serial_out(up
, UART_IER
, 0);
1151 uart_console_write(&up
->port
, s
, count
, serial_hsu_console_putchar
);
1154 * Finally, wait for transmitter to become empty
1155 * and restore the IER
1158 serial_out(up
, UART_IER
, ier
);
1161 spin_unlock(&up
->port
.lock
);
1162 local_irq_restore(flags
);
1165 static struct console serial_hsu_console
;
1168 serial_hsu_console_setup(struct console
*co
, char *options
)
1170 struct uart_hsu_port
*up
;
1177 if (co
->index
== -1 || co
->index
>= serial_hsu_reg
.nr
)
1179 up
= serial_hsu_ports
[co
->index
];
1184 uart_parse_options(options
, &baud
, &parity
, &bits
, &flow
);
1186 ret
= uart_set_options(&up
->port
, co
, baud
, parity
, bits
, flow
);
1191 static struct console serial_hsu_console
= {
1193 .write
= serial_hsu_console_write
,
1194 .device
= uart_console_device
,
1195 .setup
= serial_hsu_console_setup
,
1196 .flags
= CON_PRINTBUFFER
,
1198 .data
= &serial_hsu_reg
,
1202 struct uart_ops serial_hsu_pops
= {
1203 .tx_empty
= serial_hsu_tx_empty
,
1204 .set_mctrl
= serial_hsu_set_mctrl
,
1205 .get_mctrl
= serial_hsu_get_mctrl
,
1206 .stop_tx
= serial_hsu_stop_tx
,
1207 .start_tx
= serial_hsu_start_tx
,
1208 .stop_rx
= serial_hsu_stop_rx
,
1209 .enable_ms
= serial_hsu_enable_ms
,
1210 .break_ctl
= serial_hsu_break_ctl
,
1211 .startup
= serial_hsu_startup
,
1212 .shutdown
= serial_hsu_shutdown
,
1213 .set_termios
= serial_hsu_set_termios
,
1214 .pm
= serial_hsu_pm
,
1215 .type
= serial_hsu_type
,
1216 .release_port
= serial_hsu_release_port
,
1217 .request_port
= serial_hsu_request_port
,
1218 .config_port
= serial_hsu_config_port
,
1219 .verify_port
= serial_hsu_verify_port
,
1222 static struct uart_driver serial_hsu_reg
= {
1223 .owner
= THIS_MODULE
,
1224 .driver_name
= "MFD serial",
1225 .dev_name
= "ttyMFD",
1232 static int serial_hsu_suspend(struct pci_dev
*pdev
, pm_message_t state
)
1234 void *priv
= pci_get_drvdata(pdev
);
1235 struct uart_hsu_port
*up
;
1237 /* Make sure this is not the internal dma controller */
1238 if (priv
&& (pdev
->device
!= 0x081E)) {
1240 uart_suspend_port(&serial_hsu_reg
, &up
->port
);
1243 pci_save_state(pdev
);
1244 pci_set_power_state(pdev
, pci_choose_state(pdev
, state
));
1248 static int serial_hsu_resume(struct pci_dev
*pdev
)
1250 void *priv
= pci_get_drvdata(pdev
);
1251 struct uart_hsu_port
*up
;
1254 pci_set_power_state(pdev
, PCI_D0
);
1255 pci_restore_state(pdev
);
1257 ret
= pci_enable_device(pdev
);
1259 dev_warn(&pdev
->dev
,
1260 "HSU: can't re-enable device, try to continue\n");
1262 if (priv
&& (pdev
->device
!= 0x081E)) {
1264 uart_resume_port(&serial_hsu_reg
, &up
->port
);
1269 #define serial_hsu_suspend NULL
1270 #define serial_hsu_resume NULL
1273 /* temp global pointer before we settle down on using one or four PCI dev */
1274 static struct hsu_port
*phsu
;
1276 static int serial_hsu_probe(struct pci_dev
*pdev
,
1277 const struct pci_device_id
*ent
)
1279 struct uart_hsu_port
*uport
;
1282 printk(KERN_INFO
"HSU: found PCI Serial controller(ID: %04x:%04x)\n",
1283 pdev
->vendor
, pdev
->device
);
1285 switch (pdev
->device
) {
1296 /* internal DMA controller */
1300 dev_err(&pdev
->dev
, "HSU: out of index!");
1304 ret
= pci_enable_device(pdev
);
1309 /* DMA controller */
1310 ret
= request_irq(pdev
->irq
, dma_irq
, 0, "hsu_dma", phsu
);
1312 dev_err(&pdev
->dev
, "can not get IRQ\n");
1315 pci_set_drvdata(pdev
, phsu
);
1318 uport
= &phsu
->port
[index
];
1319 uport
->port
.irq
= pdev
->irq
;
1320 uport
->port
.dev
= &pdev
->dev
;
1321 uport
->dev
= &pdev
->dev
;
1323 ret
= request_irq(pdev
->irq
, port_irq
, 0, uport
->name
, uport
);
1325 dev_err(&pdev
->dev
, "can not get IRQ\n");
1328 uart_add_one_port(&serial_hsu_reg
, &uport
->port
);
1330 #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
1332 register_console(&serial_hsu_console
);
1333 uport
->port
.cons
= &serial_hsu_console
;
1336 pci_set_drvdata(pdev
, uport
);
1342 pci_disable_device(pdev
);
1346 static void hsu_dma_rx_timeout(unsigned long data
)
1348 struct hsu_dma_chan
*chan
= (void *)data
;
1349 struct uart_hsu_port
*up
= chan
->uport
;
1350 struct hsu_dma_buffer
*dbuf
= &up
->rxbuf
;
1352 unsigned long flags
;
1354 spin_lock_irqsave(&up
->port
.lock
, flags
);
1356 count
= chan_readl(chan
, HSU_CH_D0SAR
) - dbuf
->dma_addr
;
1359 mod_timer(&chan
->rx_timer
, jiffies
+ HSU_DMA_TIMEOUT_CHECK_FREQ
);
1365 spin_unlock_irqrestore(&up
->port
.lock
, flags
);
1368 static void hsu_global_init(void)
1370 struct hsu_port
*hsu
;
1371 struct uart_hsu_port
*uport
;
1372 struct hsu_dma_chan
*dchan
;
1375 hsu
= kzalloc(sizeof(struct hsu_port
), GFP_KERNEL
);
1379 /* Get basic io resource and map it */
1380 hsu
->paddr
= 0xffa28000;
1381 hsu
->iolen
= 0x1000;
1383 if (!(request_mem_region(hsu
->paddr
, hsu
->iolen
, "HSU global")))
1384 pr_warning("HSU: error in request mem region\n");
1386 hsu
->reg
= ioremap_nocache((unsigned long)hsu
->paddr
, hsu
->iolen
);
1388 pr_err("HSU: error in ioremap\n");
1390 goto err_free_region
;
1393 /* Initialise the 3 UART ports */
1395 for (i
= 0; i
< 3; i
++) {
1396 uport
->port
.type
= PORT_MFD
;
1397 uport
->port
.iotype
= UPIO_MEM
;
1398 uport
->port
.mapbase
= (resource_size_t
)hsu
->paddr
1399 + HSU_PORT_REG_OFFSET
1400 + i
* HSU_PORT_REG_LENGTH
;
1401 uport
->port
.membase
= hsu
->reg
+ HSU_PORT_REG_OFFSET
1402 + i
* HSU_PORT_REG_LENGTH
;
1404 sprintf(uport
->name
, "hsu_port%d", i
);
1405 uport
->port
.fifosize
= 64;
1406 uport
->port
.ops
= &serial_hsu_pops
;
1407 uport
->port
.line
= i
;
1408 uport
->port
.flags
= UPF_IOREMAP
;
1409 /* set the scalable maxim support rate to 2746800 bps */
1410 uport
->port
.uartclk
= 115200 * 24 * 16;
1413 uport
->txc
= &hsu
->chans
[i
* 2];
1414 uport
->rxc
= &hsu
->chans
[i
* 2 + 1];
1416 serial_hsu_ports
[i
] = uport
;
1421 /* Initialise 6 dma channels */
1423 for (i
= 0; i
< 6; i
++) {
1425 dchan
->dirt
= (i
& 0x1) ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
;
1426 dchan
->uport
= &hsu
->port
[i
/2];
1427 dchan
->reg
= hsu
->reg
+ HSU_DMA_CHANS_REG_OFFSET
+
1428 i
* HSU_DMA_CHANS_REG_LENGTH
;
1430 /* Work around for RX */
1431 if (dchan
->dirt
== DMA_FROM_DEVICE
) {
1432 init_timer(&dchan
->rx_timer
);
1433 dchan
->rx_timer
.function
= hsu_dma_rx_timeout
;
1434 dchan
->rx_timer
.data
= (unsigned long)dchan
;
1440 hsu_debugfs_init(hsu
);
1444 release_mem_region(hsu
->paddr
, hsu
->iolen
);
1449 static void serial_hsu_remove(struct pci_dev
*pdev
)
1451 void *priv
= pci_get_drvdata(pdev
);
1452 struct uart_hsu_port
*up
;
1457 /* For port 0/1/2, priv is the address of uart_hsu_port */
1458 if (pdev
->device
!= 0x081E) {
1460 uart_remove_one_port(&serial_hsu_reg
, &up
->port
);
1463 pci_set_drvdata(pdev
, NULL
);
1464 free_irq(pdev
->irq
, priv
);
1465 pci_disable_device(pdev
);
1468 /* First 3 are UART ports, and the 4th is the DMA */
1469 static const struct pci_device_id pci_ids
[] __devinitdata
= {
1470 { PCI_DEVICE(PCI_VENDOR_ID_INTEL
, 0x081B) },
1471 { PCI_DEVICE(PCI_VENDOR_ID_INTEL
, 0x081C) },
1472 { PCI_DEVICE(PCI_VENDOR_ID_INTEL
, 0x081D) },
1473 { PCI_DEVICE(PCI_VENDOR_ID_INTEL
, 0x081E) },
1477 static struct pci_driver hsu_pci_driver
= {
1478 .name
= "HSU serial",
1479 .id_table
= pci_ids
,
1480 .probe
= serial_hsu_probe
,
1481 .remove
= __devexit_p(serial_hsu_remove
),
1482 .suspend
= serial_hsu_suspend
,
1483 .resume
= serial_hsu_resume
,
1486 static int __init
hsu_pci_init(void)
1492 ret
= uart_register_driver(&serial_hsu_reg
);
1496 return pci_register_driver(&hsu_pci_driver
);
1499 static void __exit
hsu_pci_exit(void)
1501 pci_unregister_driver(&hsu_pci_driver
);
1502 uart_unregister_driver(&serial_hsu_reg
);
1504 hsu_debugfs_remove(phsu
);
1509 module_init(hsu_pci_init
);
1510 module_exit(hsu_pci_exit
);
1512 MODULE_LICENSE("GPL v2");
1513 MODULE_ALIAS("platform:medfield-hsu");