2 * Broadcom BCM63xx SPI controller support
4 * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org>
5 * Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
18 #include <linux/kernel.h>
19 #include <linux/clk.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/delay.h>
24 #include <linux/interrupt.h>
25 #include <linux/spi/spi.h>
26 #include <linux/completion.h>
27 #include <linux/err.h>
28 #include <linux/pm_runtime.h>
30 /* BCM 6338/6348 SPI core */
31 #define SPI_6348_RSET_SIZE 64
32 #define SPI_6348_CMD 0x00 /* 16-bits register */
33 #define SPI_6348_INT_STATUS 0x02
34 #define SPI_6348_INT_MASK_ST 0x03
35 #define SPI_6348_INT_MASK 0x04
36 #define SPI_6348_ST 0x05
37 #define SPI_6348_CLK_CFG 0x06
38 #define SPI_6348_FILL_BYTE 0x07
39 #define SPI_6348_MSG_TAIL 0x09
40 #define SPI_6348_RX_TAIL 0x0b
41 #define SPI_6348_MSG_CTL 0x40 /* 8-bits register */
42 #define SPI_6348_MSG_CTL_WIDTH 8
43 #define SPI_6348_MSG_DATA 0x41
44 #define SPI_6348_MSG_DATA_SIZE 0x3f
45 #define SPI_6348_RX_DATA 0x80
46 #define SPI_6348_RX_DATA_SIZE 0x3f
48 /* BCM 3368/6358/6262/6368 SPI core */
49 #define SPI_6358_RSET_SIZE 1804
50 #define SPI_6358_MSG_CTL 0x00 /* 16-bits register */
51 #define SPI_6358_MSG_CTL_WIDTH 16
52 #define SPI_6358_MSG_DATA 0x02
53 #define SPI_6358_MSG_DATA_SIZE 0x21e
54 #define SPI_6358_RX_DATA 0x400
55 #define SPI_6358_RX_DATA_SIZE 0x220
56 #define SPI_6358_CMD 0x700 /* 16-bits register */
57 #define SPI_6358_INT_STATUS 0x702
58 #define SPI_6358_INT_MASK_ST 0x703
59 #define SPI_6358_INT_MASK 0x704
60 #define SPI_6358_ST 0x705
61 #define SPI_6358_CLK_CFG 0x706
62 #define SPI_6358_FILL_BYTE 0x707
63 #define SPI_6358_MSG_TAIL 0x709
64 #define SPI_6358_RX_TAIL 0x70B
66 /* Shared SPI definitions */
68 /* Message configuration */
69 #define SPI_FD_RW 0x00
72 #define SPI_BYTE_CNT_SHIFT 0
73 #define SPI_6348_MSG_TYPE_SHIFT 6
74 #define SPI_6358_MSG_TYPE_SHIFT 14
77 #define SPI_CMD_NOOP 0x00
78 #define SPI_CMD_SOFT_RESET 0x01
79 #define SPI_CMD_HARD_RESET 0x02
80 #define SPI_CMD_START_IMMEDIATE 0x03
81 #define SPI_CMD_COMMAND_SHIFT 0
82 #define SPI_CMD_COMMAND_MASK 0x000f
83 #define SPI_CMD_DEVICE_ID_SHIFT 4
84 #define SPI_CMD_PREPEND_BYTE_CNT_SHIFT 8
85 #define SPI_CMD_ONE_BYTE_SHIFT 11
86 #define SPI_CMD_ONE_WIRE_SHIFT 12
87 #define SPI_DEV_ID_0 0
88 #define SPI_DEV_ID_1 1
89 #define SPI_DEV_ID_2 2
90 #define SPI_DEV_ID_3 3
93 #define SPI_INTR_CMD_DONE 0x01
94 #define SPI_INTR_RX_OVERFLOW 0x02
95 #define SPI_INTR_TX_UNDERFLOW 0x04
96 #define SPI_INTR_TX_OVERFLOW 0x08
97 #define SPI_INTR_RX_UNDERFLOW 0x10
98 #define SPI_INTR_CLEAR_ALL 0x1f
101 #define SPI_RX_EMPTY 0x02
102 #define SPI_CMD_BUSY 0x04
103 #define SPI_SERIAL_BUSY 0x08
105 /* Clock configuration */
106 #define SPI_CLK_20MHZ 0x00
107 #define SPI_CLK_0_391MHZ 0x01
108 #define SPI_CLK_0_781MHZ 0x02 /* default */
109 #define SPI_CLK_1_563MHZ 0x03
110 #define SPI_CLK_3_125MHZ 0x04
111 #define SPI_CLK_6_250MHZ 0x05
112 #define SPI_CLK_12_50MHZ 0x06
113 #define SPI_CLK_MASK 0x07
114 #define SPI_SSOFFTIME_MASK 0x38
115 #define SPI_SSOFFTIME_SHIFT 3
116 #define SPI_BYTE_SWAP 0x80
118 enum bcm63xx_regs_spi
{
136 #define BCM63XX_SPI_MAX_PREPEND 15
138 #define BCM63XX_SPI_MAX_CS 8
139 #define BCM63XX_SPI_BUS_NUM 0
142 struct completion done
;
148 const unsigned long *reg_offsets
;
150 unsigned int msg_type_shift
;
151 unsigned int msg_ctl_width
;
155 const u8 __iomem
*rx_io
;
158 struct platform_device
*pdev
;
161 static inline u8
bcm_spi_readb(struct bcm63xx_spi
*bs
,
164 return readb(bs
->regs
+ bs
->reg_offsets
[offset
]);
167 static inline u16
bcm_spi_readw(struct bcm63xx_spi
*bs
,
170 #ifdef CONFIG_CPU_BIG_ENDIAN
171 return ioread16be(bs
->regs
+ bs
->reg_offsets
[offset
]);
173 return readw(bs
->regs
+ bs
->reg_offsets
[offset
]);
177 static inline void bcm_spi_writeb(struct bcm63xx_spi
*bs
,
178 u8 value
, unsigned int offset
)
180 writeb(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
183 static inline void bcm_spi_writew(struct bcm63xx_spi
*bs
,
184 u16 value
, unsigned int offset
)
186 #ifdef CONFIG_CPU_BIG_ENDIAN
187 iowrite16be(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
189 writew(value
, bs
->regs
+ bs
->reg_offsets
[offset
]);
193 static const unsigned bcm63xx_spi_freq_table
[SPI_CLK_MASK
][2] = {
194 { 20000000, SPI_CLK_20MHZ
},
195 { 12500000, SPI_CLK_12_50MHZ
},
196 { 6250000, SPI_CLK_6_250MHZ
},
197 { 3125000, SPI_CLK_3_125MHZ
},
198 { 1563000, SPI_CLK_1_563MHZ
},
199 { 781000, SPI_CLK_0_781MHZ
},
200 { 391000, SPI_CLK_0_391MHZ
}
203 static void bcm63xx_spi_setup_transfer(struct spi_device
*spi
,
204 struct spi_transfer
*t
)
206 struct bcm63xx_spi
*bs
= spi_master_get_devdata(spi
->master
);
210 /* Find the closest clock configuration */
211 for (i
= 0; i
< SPI_CLK_MASK
; i
++) {
212 if (t
->speed_hz
>= bcm63xx_spi_freq_table
[i
][0]) {
213 clk_cfg
= bcm63xx_spi_freq_table
[i
][1];
218 /* No matching configuration found, default to lowest */
219 if (i
== SPI_CLK_MASK
)
220 clk_cfg
= SPI_CLK_0_391MHZ
;
222 /* clear existing clock configuration bits of the register */
223 reg
= bcm_spi_readb(bs
, SPI_CLK_CFG
);
224 reg
&= ~SPI_CLK_MASK
;
227 bcm_spi_writeb(bs
, reg
, SPI_CLK_CFG
);
228 dev_dbg(&spi
->dev
, "Setting clock register to %02x (hz %d)\n",
229 clk_cfg
, t
->speed_hz
);
232 /* the spi->mode bits understood by this driver: */
233 #define MODEBITS (SPI_CPOL | SPI_CPHA)
235 static int bcm63xx_txrx_bufs(struct spi_device
*spi
, struct spi_transfer
*first
,
236 unsigned int num_transfers
)
238 struct bcm63xx_spi
*bs
= spi_master_get_devdata(spi
->master
);
241 unsigned int i
, timeout
= 0, prepend_len
= 0, len
= 0;
242 struct spi_transfer
*t
= first
;
246 /* Disable the CMD_DONE interrupt */
247 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
249 dev_dbg(&spi
->dev
, "txrx: tx %p, rx %p, len %d\n",
250 t
->tx_buf
, t
->rx_buf
, t
->len
);
252 if (num_transfers
> 1 && t
->tx_buf
&& t
->len
<= BCM63XX_SPI_MAX_PREPEND
)
253 prepend_len
= t
->len
;
255 /* prepare the buffer */
256 for (i
= 0; i
< num_transfers
; i
++) {
259 memcpy_toio(bs
->tx_io
+ len
, t
->tx_buf
, t
->len
);
261 /* don't prepend more than one tx */
268 /* prepend is half-duplex write only */
275 t
= list_entry(t
->transfer_list
.next
, struct spi_transfer
,
279 reinit_completion(&bs
->done
);
281 /* Fill in the Message control register */
282 msg_ctl
= (len
<< SPI_BYTE_CNT_SHIFT
);
284 if (do_rx
&& do_tx
&& prepend_len
== 0)
285 msg_ctl
|= (SPI_FD_RW
<< bs
->msg_type_shift
);
287 msg_ctl
|= (SPI_HD_R
<< bs
->msg_type_shift
);
289 msg_ctl
|= (SPI_HD_W
<< bs
->msg_type_shift
);
291 switch (bs
->msg_ctl_width
) {
293 bcm_spi_writeb(bs
, msg_ctl
, SPI_MSG_CTL
);
296 bcm_spi_writew(bs
, msg_ctl
, SPI_MSG_CTL
);
300 /* Issue the transfer */
301 cmd
= SPI_CMD_START_IMMEDIATE
;
302 cmd
|= (prepend_len
<< SPI_CMD_PREPEND_BYTE_CNT_SHIFT
);
303 cmd
|= (spi
->chip_select
<< SPI_CMD_DEVICE_ID_SHIFT
);
304 bcm_spi_writew(bs
, cmd
, SPI_CMD
);
306 /* Enable the CMD_DONE interrupt */
307 bcm_spi_writeb(bs
, SPI_INTR_CMD_DONE
, SPI_INT_MASK
);
309 timeout
= wait_for_completion_timeout(&bs
->done
, HZ
);
318 /* Read out all the data */
319 for (i
= 0; i
< num_transfers
; i
++) {
321 memcpy_fromio(t
->rx_buf
, bs
->rx_io
+ len
, t
->len
);
323 if (t
!= first
|| prepend_len
== 0)
326 t
= list_entry(t
->transfer_list
.next
, struct spi_transfer
,
333 static int bcm63xx_spi_transfer_one(struct spi_master
*master
,
334 struct spi_message
*m
)
336 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
337 struct spi_transfer
*t
, *first
= NULL
;
338 struct spi_device
*spi
= m
->spi
;
340 unsigned int n_transfers
= 0, total_len
= 0;
341 bool can_use_prepend
= false;
344 * This SPI controller does not support keeping CS active after a
346 * Work around this by merging as many transfers we can into one big
347 * full-duplex transfers.
349 list_for_each_entry(t
, &m
->transfers
, transfer_list
) {
356 if (n_transfers
== 2 && !first
->rx_buf
&& !t
->tx_buf
&&
357 first
->len
<= BCM63XX_SPI_MAX_PREPEND
)
358 can_use_prepend
= true;
359 else if (can_use_prepend
&& t
->tx_buf
)
360 can_use_prepend
= false;
362 /* we can only transfer one fifo worth of data */
363 if ((can_use_prepend
&&
364 total_len
> (bs
->fifo_size
+ BCM63XX_SPI_MAX_PREPEND
)) ||
365 (!can_use_prepend
&& total_len
> bs
->fifo_size
)) {
366 dev_err(&spi
->dev
, "unable to do transfers larger than FIFO size (%i > %i)\n",
367 total_len
, bs
->fifo_size
);
372 /* all combined transfers have to have the same speed */
373 if (t
->speed_hz
!= first
->speed_hz
) {
374 dev_err(&spi
->dev
, "unable to change speed between transfers\n");
379 /* CS will be deasserted directly after transfer */
380 if (t
->delay_usecs
) {
381 dev_err(&spi
->dev
, "unable to keep CS asserted after transfer\n");
387 list_is_last(&t
->transfer_list
, &m
->transfers
)) {
388 /* configure adapter for a new transfer */
389 bcm63xx_spi_setup_transfer(spi
, first
);
392 status
= bcm63xx_txrx_bufs(spi
, first
, n_transfers
);
396 m
->actual_length
+= total_len
;
401 can_use_prepend
= false;
406 spi_finalize_current_message(master
);
411 /* This driver supports single master mode only. Hence
412 * CMD_DONE is the only interrupt we care about
414 static irqreturn_t
bcm63xx_spi_interrupt(int irq
, void *dev_id
)
416 struct spi_master
*master
= (struct spi_master
*)dev_id
;
417 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
420 /* Read interupts and clear them immediately */
421 intr
= bcm_spi_readb(bs
, SPI_INT_STATUS
);
422 bcm_spi_writeb(bs
, SPI_INTR_CLEAR_ALL
, SPI_INT_STATUS
);
423 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
425 /* A transfer completed */
426 if (intr
& SPI_INTR_CMD_DONE
)
432 static const unsigned long bcm6348_spi_reg_offsets
[] = {
433 [SPI_CMD
] = SPI_6348_CMD
,
434 [SPI_INT_STATUS
] = SPI_6348_INT_STATUS
,
435 [SPI_INT_MASK_ST
] = SPI_6348_INT_MASK_ST
,
436 [SPI_INT_MASK
] = SPI_6348_INT_MASK
,
437 [SPI_ST
] = SPI_6348_ST
,
438 [SPI_CLK_CFG
] = SPI_6348_CLK_CFG
,
439 [SPI_FILL_BYTE
] = SPI_6348_FILL_BYTE
,
440 [SPI_MSG_TAIL
] = SPI_6348_MSG_TAIL
,
441 [SPI_RX_TAIL
] = SPI_6348_RX_TAIL
,
442 [SPI_MSG_CTL
] = SPI_6348_MSG_CTL
,
443 [SPI_MSG_DATA
] = SPI_6348_MSG_DATA
,
444 [SPI_RX_DATA
] = SPI_6348_RX_DATA
,
445 [SPI_MSG_TYPE_SHIFT
] = SPI_6348_MSG_TYPE_SHIFT
,
446 [SPI_MSG_CTL_WIDTH
] = SPI_6348_MSG_CTL_WIDTH
,
447 [SPI_MSG_DATA_SIZE
] = SPI_6348_MSG_DATA_SIZE
,
450 static const unsigned long bcm6358_spi_reg_offsets
[] = {
451 [SPI_CMD
] = SPI_6358_CMD
,
452 [SPI_INT_STATUS
] = SPI_6358_INT_STATUS
,
453 [SPI_INT_MASK_ST
] = SPI_6358_INT_MASK_ST
,
454 [SPI_INT_MASK
] = SPI_6358_INT_MASK
,
455 [SPI_ST
] = SPI_6358_ST
,
456 [SPI_CLK_CFG
] = SPI_6358_CLK_CFG
,
457 [SPI_FILL_BYTE
] = SPI_6358_FILL_BYTE
,
458 [SPI_MSG_TAIL
] = SPI_6358_MSG_TAIL
,
459 [SPI_RX_TAIL
] = SPI_6358_RX_TAIL
,
460 [SPI_MSG_CTL
] = SPI_6358_MSG_CTL
,
461 [SPI_MSG_DATA
] = SPI_6358_MSG_DATA
,
462 [SPI_RX_DATA
] = SPI_6358_RX_DATA
,
463 [SPI_MSG_TYPE_SHIFT
] = SPI_6358_MSG_TYPE_SHIFT
,
464 [SPI_MSG_CTL_WIDTH
] = SPI_6358_MSG_CTL_WIDTH
,
465 [SPI_MSG_DATA_SIZE
] = SPI_6358_MSG_DATA_SIZE
,
468 static const struct platform_device_id bcm63xx_spi_dev_match
[] = {
470 .name
= "bcm6348-spi",
471 .driver_data
= (unsigned long)bcm6348_spi_reg_offsets
,
474 .name
= "bcm6358-spi",
475 .driver_data
= (unsigned long)bcm6358_spi_reg_offsets
,
481 static int bcm63xx_spi_probe(struct platform_device
*pdev
)
484 const unsigned long *bcm63xx_spireg
;
485 struct device
*dev
= &pdev
->dev
;
487 struct spi_master
*master
;
489 struct bcm63xx_spi
*bs
;
492 if (!pdev
->id_entry
->driver_data
)
495 bcm63xx_spireg
= (const unsigned long *)pdev
->id_entry
->driver_data
;
497 irq
= platform_get_irq(pdev
, 0);
499 dev_err(dev
, "no irq\n");
503 clk
= devm_clk_get(dev
, "spi");
505 dev_err(dev
, "no clock for device\n");
509 master
= spi_alloc_master(dev
, sizeof(*bs
));
511 dev_err(dev
, "out of memory\n");
515 bs
= spi_master_get_devdata(master
);
516 init_completion(&bs
->done
);
518 platform_set_drvdata(pdev
, master
);
521 r
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
522 bs
->regs
= devm_ioremap_resource(&pdev
->dev
, r
);
523 if (IS_ERR(bs
->regs
)) {
524 ret
= PTR_ERR(bs
->regs
);
530 bs
->reg_offsets
= bcm63xx_spireg
;
531 bs
->fifo_size
= bs
->reg_offsets
[SPI_MSG_DATA_SIZE
];
533 ret
= devm_request_irq(&pdev
->dev
, irq
, bcm63xx_spi_interrupt
, 0,
536 dev_err(dev
, "unable to request irq\n");
540 master
->bus_num
= BCM63XX_SPI_BUS_NUM
;
541 master
->num_chipselect
= BCM63XX_SPI_MAX_CS
;
542 master
->transfer_one_message
= bcm63xx_spi_transfer_one
;
543 master
->mode_bits
= MODEBITS
;
544 master
->bits_per_word_mask
= SPI_BPW_MASK(8);
545 master
->auto_runtime_pm
= true;
546 bs
->msg_type_shift
= bs
->reg_offsets
[SPI_MSG_TYPE_SHIFT
];
547 bs
->msg_ctl_width
= bs
->reg_offsets
[SPI_MSG_CTL_WIDTH
];
548 bs
->tx_io
= (u8
*)(bs
->regs
+ bs
->reg_offsets
[SPI_MSG_DATA
]);
549 bs
->rx_io
= (const u8
*)(bs
->regs
+ bs
->reg_offsets
[SPI_RX_DATA
]);
551 /* Initialize hardware */
552 ret
= clk_prepare_enable(bs
->clk
);
556 bcm_spi_writeb(bs
, SPI_INTR_CLEAR_ALL
, SPI_INT_STATUS
);
558 /* register and we are done */
559 ret
= devm_spi_register_master(dev
, master
);
561 dev_err(dev
, "spi register failed\n");
562 goto out_clk_disable
;
565 dev_info(dev
, "at %pr (irq %d, FIFOs size %d)\n",
566 r
, irq
, bs
->fifo_size
);
571 clk_disable_unprepare(clk
);
573 spi_master_put(master
);
577 static int bcm63xx_spi_remove(struct platform_device
*pdev
)
579 struct spi_master
*master
= platform_get_drvdata(pdev
);
580 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
582 /* reset spi block */
583 bcm_spi_writeb(bs
, 0, SPI_INT_MASK
);
586 clk_disable_unprepare(bs
->clk
);
591 #ifdef CONFIG_PM_SLEEP
592 static int bcm63xx_spi_suspend(struct device
*dev
)
594 struct spi_master
*master
= dev_get_drvdata(dev
);
595 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
597 spi_master_suspend(master
);
599 clk_disable_unprepare(bs
->clk
);
604 static int bcm63xx_spi_resume(struct device
*dev
)
606 struct spi_master
*master
= dev_get_drvdata(dev
);
607 struct bcm63xx_spi
*bs
= spi_master_get_devdata(master
);
610 ret
= clk_prepare_enable(bs
->clk
);
614 spi_master_resume(master
);
620 static const struct dev_pm_ops bcm63xx_spi_pm_ops
= {
621 SET_SYSTEM_SLEEP_PM_OPS(bcm63xx_spi_suspend
, bcm63xx_spi_resume
)
624 static struct platform_driver bcm63xx_spi_driver
= {
626 .name
= "bcm63xx-spi",
627 .pm
= &bcm63xx_spi_pm_ops
,
629 .id_table
= bcm63xx_spi_dev_match
,
630 .probe
= bcm63xx_spi_probe
,
631 .remove
= bcm63xx_spi_remove
,
634 module_platform_driver(bcm63xx_spi_driver
);
636 MODULE_ALIAS("platform:bcm63xx_spi");
637 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
638 MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>");
639 MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver");
640 MODULE_LICENSE("GPL");