2 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
4 * Copyright (C) 2008-2012 ST-Ericsson AB
5 * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
7 * Author: Linus Walleij <linus.walleij@stericsson.com>
9 * Initial version inspired by:
10 * linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
11 * Initial adoption to PL022 by:
12 * Sachin Verma <sachin.verma@st.com>
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
25 #include <linux/init.h>
26 #include <linux/module.h>
27 #include <linux/device.h>
28 #include <linux/ioport.h>
29 #include <linux/errno.h>
30 #include <linux/interrupt.h>
31 #include <linux/spi/spi.h>
32 #include <linux/delay.h>
33 #include <linux/clk.h>
34 #include <linux/err.h>
35 #include <linux/amba/bus.h>
36 #include <linux/amba/pl022.h>
38 #include <linux/slab.h>
39 #include <linux/dmaengine.h>
40 #include <linux/dma-mapping.h>
41 #include <linux/scatterlist.h>
42 #include <linux/pm_runtime.h>
43 #include <linux/gpio.h>
44 #include <linux/of_gpio.h>
45 #include <linux/pinctrl/consumer.h>
48 * This macro is used to define some register default values.
49 * reg is masked with mask, the OR:ed with an (again masked)
50 * val shifted sb steps to the left.
52 #define SSP_WRITE_BITS(reg, val, mask, sb) \
53 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
56 * This macro is also used to define some default values.
57 * It will just shift val by sb steps to the left and mask
58 * the result with mask.
60 #define GEN_MASK_BITS(val, mask, sb) \
61 (((val)<<(sb)) & (mask))
64 #define DO_NOT_DRIVE_TX 1
66 #define DO_NOT_QUEUE_DMA 0
73 * Macros to access SSP Registers with their offsets
75 #define SSP_CR0(r) (r + 0x000)
76 #define SSP_CR1(r) (r + 0x004)
77 #define SSP_DR(r) (r + 0x008)
78 #define SSP_SR(r) (r + 0x00C)
79 #define SSP_CPSR(r) (r + 0x010)
80 #define SSP_IMSC(r) (r + 0x014)
81 #define SSP_RIS(r) (r + 0x018)
82 #define SSP_MIS(r) (r + 0x01C)
83 #define SSP_ICR(r) (r + 0x020)
84 #define SSP_DMACR(r) (r + 0x024)
85 #define SSP_CSR(r) (r + 0x030) /* vendor extension */
86 #define SSP_ITCR(r) (r + 0x080)
87 #define SSP_ITIP(r) (r + 0x084)
88 #define SSP_ITOP(r) (r + 0x088)
89 #define SSP_TDR(r) (r + 0x08C)
91 #define SSP_PID0(r) (r + 0xFE0)
92 #define SSP_PID1(r) (r + 0xFE4)
93 #define SSP_PID2(r) (r + 0xFE8)
94 #define SSP_PID3(r) (r + 0xFEC)
96 #define SSP_CID0(r) (r + 0xFF0)
97 #define SSP_CID1(r) (r + 0xFF4)
98 #define SSP_CID2(r) (r + 0xFF8)
99 #define SSP_CID3(r) (r + 0xFFC)
102 * SSP Control Register 0 - SSP_CR0
104 #define SSP_CR0_MASK_DSS (0x0FUL << 0)
105 #define SSP_CR0_MASK_FRF (0x3UL << 4)
106 #define SSP_CR0_MASK_SPO (0x1UL << 6)
107 #define SSP_CR0_MASK_SPH (0x1UL << 7)
108 #define SSP_CR0_MASK_SCR (0xFFUL << 8)
111 * The ST version of this block moves som bits
112 * in SSP_CR0 and extends it to 32 bits
114 #define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
115 #define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
116 #define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
117 #define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
120 * SSP Control Register 0 - SSP_CR1
122 #define SSP_CR1_MASK_LBM (0x1UL << 0)
123 #define SSP_CR1_MASK_SSE (0x1UL << 1)
124 #define SSP_CR1_MASK_MS (0x1UL << 2)
125 #define SSP_CR1_MASK_SOD (0x1UL << 3)
128 * The ST version of this block adds some bits
131 #define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
132 #define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
133 #define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
134 #define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
135 #define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
136 /* This one is only in the PL023 variant */
137 #define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
140 * SSP Status Register - SSP_SR
142 #define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
143 #define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
144 #define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
145 #define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
146 #define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
149 * SSP Clock Prescale Register - SSP_CPSR
151 #define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
154 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
156 #define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
157 #define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
158 #define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
159 #define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
162 * SSP Raw Interrupt Status Register - SSP_RIS
164 /* Receive Overrun Raw Interrupt status */
165 #define SSP_RIS_MASK_RORRIS (0x1UL << 0)
166 /* Receive Timeout Raw Interrupt status */
167 #define SSP_RIS_MASK_RTRIS (0x1UL << 1)
168 /* Receive FIFO Raw Interrupt status */
169 #define SSP_RIS_MASK_RXRIS (0x1UL << 2)
170 /* Transmit FIFO Raw Interrupt status */
171 #define SSP_RIS_MASK_TXRIS (0x1UL << 3)
174 * SSP Masked Interrupt Status Register - SSP_MIS
176 /* Receive Overrun Masked Interrupt status */
177 #define SSP_MIS_MASK_RORMIS (0x1UL << 0)
178 /* Receive Timeout Masked Interrupt status */
179 #define SSP_MIS_MASK_RTMIS (0x1UL << 1)
180 /* Receive FIFO Masked Interrupt status */
181 #define SSP_MIS_MASK_RXMIS (0x1UL << 2)
182 /* Transmit FIFO Masked Interrupt status */
183 #define SSP_MIS_MASK_TXMIS (0x1UL << 3)
186 * SSP Interrupt Clear Register - SSP_ICR
188 /* Receive Overrun Raw Clear Interrupt bit */
189 #define SSP_ICR_MASK_RORIC (0x1UL << 0)
190 /* Receive Timeout Clear Interrupt bit */
191 #define SSP_ICR_MASK_RTIC (0x1UL << 1)
194 * SSP DMA Control Register - SSP_DMACR
196 /* Receive DMA Enable bit */
197 #define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
198 /* Transmit DMA Enable bit */
199 #define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
202 * SSP Chip Select Control Register - SSP_CSR
205 #define SSP_CSR_CSVALUE_MASK (0x1FUL << 0)
208 * SSP Integration Test control Register - SSP_ITCR
210 #define SSP_ITCR_MASK_ITEN (0x1UL << 0)
211 #define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
214 * SSP Integration Test Input Register - SSP_ITIP
216 #define ITIP_MASK_SSPRXD (0x1UL << 0)
217 #define ITIP_MASK_SSPFSSIN (0x1UL << 1)
218 #define ITIP_MASK_SSPCLKIN (0x1UL << 2)
219 #define ITIP_MASK_RXDMAC (0x1UL << 3)
220 #define ITIP_MASK_TXDMAC (0x1UL << 4)
221 #define ITIP_MASK_SSPTXDIN (0x1UL << 5)
224 * SSP Integration Test output Register - SSP_ITOP
226 #define ITOP_MASK_SSPTXD (0x1UL << 0)
227 #define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
228 #define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
229 #define ITOP_MASK_SSPOEn (0x1UL << 3)
230 #define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
231 #define ITOP_MASK_RORINTR (0x1UL << 5)
232 #define ITOP_MASK_RTINTR (0x1UL << 6)
233 #define ITOP_MASK_RXINTR (0x1UL << 7)
234 #define ITOP_MASK_TXINTR (0x1UL << 8)
235 #define ITOP_MASK_INTR (0x1UL << 9)
236 #define ITOP_MASK_RXDMABREQ (0x1UL << 10)
237 #define ITOP_MASK_RXDMASREQ (0x1UL << 11)
238 #define ITOP_MASK_TXDMABREQ (0x1UL << 12)
239 #define ITOP_MASK_TXDMASREQ (0x1UL << 13)
242 * SSP Test Data Register - SSP_TDR
244 #define TDR_MASK_TESTDATA (0xFFFFFFFF)
248 * we use the spi_message.state (void *) pointer to
249 * hold a single state value, that's why all this
250 * (void *) casting is done here.
252 #define STATE_START ((void *) 0)
253 #define STATE_RUNNING ((void *) 1)
254 #define STATE_DONE ((void *) 2)
255 #define STATE_ERROR ((void *) -1)
258 * SSP State - Whether Enabled or Disabled
260 #define SSP_DISABLED (0)
261 #define SSP_ENABLED (1)
264 * SSP DMA State - Whether DMA Enabled or Disabled
266 #define SSP_DMA_DISABLED (0)
267 #define SSP_DMA_ENABLED (1)
272 #define SSP_DEFAULT_CLKRATE 0x2
273 #define SSP_DEFAULT_PRESCALE 0x40
276 * SSP Clock Parameter ranges
278 #define CPSDVR_MIN 0x02
279 #define CPSDVR_MAX 0xFE
284 * SSP Interrupt related Macros
286 #define DEFAULT_SSP_REG_IMSC 0x0UL
287 #define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
288 #define ENABLE_ALL_INTERRUPTS ( \
289 SSP_IMSC_MASK_RORIM | \
290 SSP_IMSC_MASK_RTIM | \
291 SSP_IMSC_MASK_RXIM | \
295 #define CLEAR_ALL_INTERRUPTS 0x3
297 #define SPI_POLLING_TIMEOUT 1000
300 * The type of reading going on on this chip
310 * The type of writing going on on this chip
320 * struct vendor_data - vendor-specific config parameters
321 * for PL022 derivates
322 * @fifodepth: depth of FIFOs (both)
323 * @max_bpw: maximum number of bits per word
324 * @unidir: supports unidirection transfers
325 * @extended_cr: 32 bit wide control register 0 with extra
326 * features and extra features in CR1 as found in the ST variants
327 * @pl023: supports a subset of the ST extensions called "PL023"
328 * @internal_cs_ctrl: supports chip select control register
337 bool internal_cs_ctrl
;
341 * struct pl022 - This is the private SSP driver data structure
342 * @adev: AMBA device model hookup
343 * @vendor: vendor data for the IP block
344 * @phybase: the physical memory where the SSP device resides
345 * @virtbase: the virtual memory where the SSP is mapped
346 * @clk: outgoing clock "SPICLK" for the SPI bus
347 * @master: SPI framework hookup
348 * @master_info: controller-specific data from machine setup
349 * @pump_transfers: Tasklet used in Interrupt Transfer mode
350 * @cur_msg: Pointer to current spi_message being processed
351 * @cur_transfer: Pointer to current spi_transfer
352 * @cur_chip: pointer to current clients chip(assigned from controller_state)
353 * @next_msg_cs_active: the next message in the queue has been examined
354 * and it was found that it uses the same chip select as the previous
355 * message, so we left it active after the previous transfer, and it's
357 * @tx: current position in TX buffer to be read
358 * @tx_end: end position in TX buffer to be read
359 * @rx: current position in RX buffer to be written
360 * @rx_end: end position in RX buffer to be written
361 * @read: the type of read currently going on
362 * @write: the type of write currently going on
363 * @exp_fifo_level: expected FIFO level
364 * @dma_rx_channel: optional channel for RX DMA
365 * @dma_tx_channel: optional channel for TX DMA
366 * @sgt_rx: scattertable for the RX transfer
367 * @sgt_tx: scattertable for the TX transfer
368 * @dummypage: a dummy page used for driving data on the bus with DMA
369 * @cur_cs: current chip select (gpio)
370 * @chipselects: list of chipselects (gpios)
373 struct amba_device
*adev
;
374 struct vendor_data
*vendor
;
375 resource_size_t phybase
;
376 void __iomem
*virtbase
;
378 struct spi_master
*master
;
379 struct pl022_ssp_controller
*master_info
;
380 /* Message per-transfer pump */
381 struct tasklet_struct pump_transfers
;
382 struct spi_message
*cur_msg
;
383 struct spi_transfer
*cur_transfer
;
384 struct chip_data
*cur_chip
;
385 bool next_msg_cs_active
;
390 enum ssp_reading read
;
391 enum ssp_writing write
;
393 enum ssp_rx_level_trig rx_lev_trig
;
394 enum ssp_tx_level_trig tx_lev_trig
;
396 #ifdef CONFIG_DMA_ENGINE
397 struct dma_chan
*dma_rx_channel
;
398 struct dma_chan
*dma_tx_channel
;
399 struct sg_table sgt_rx
;
400 struct sg_table sgt_tx
;
409 * struct chip_data - To maintain runtime state of SSP for each client chip
410 * @cr0: Value of control register CR0 of SSP - on later ST variants this
411 * register is 32 bits wide rather than just 16
412 * @cr1: Value of control register CR1 of SSP
413 * @dmacr: Value of DMA control Register of SSP
414 * @cpsr: Value of Clock prescale register
415 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
416 * @enable_dma: Whether to enable DMA or not
417 * @read: function ptr to be used to read when doing xfer for this chip
418 * @write: function ptr to be used to write when doing xfer for this chip
419 * @cs_control: chip select callback provided by chip
420 * @xfer_type: polling/interrupt/DMA
422 * Runtime state of the SSP controller, maintained per chip,
423 * This would be set according to the current message that would be served
432 enum ssp_reading read
;
433 enum ssp_writing write
;
434 void (*cs_control
) (u32 command
);
439 * null_cs_control - Dummy chip select function
440 * @command: select/delect the chip
442 * If no chip select function is provided by client this is used as dummy
445 static void null_cs_control(u32 command
)
447 pr_debug("pl022: dummy chip select control, CS=0x%x\n", command
);
451 * internal_cs_control - Control chip select signals via SSP_CSR.
452 * @pl022: SSP driver private data structure
453 * @command: select/delect the chip
455 * Used on controller with internal chip select control via SSP_CSR register
456 * (vendor extension). Each of the 5 LSB in the register controls one chip
459 static void internal_cs_control(struct pl022
*pl022
, u32 command
)
463 tmp
= readw(SSP_CSR(pl022
->virtbase
));
464 if (command
== SSP_CHIP_SELECT
)
465 tmp
&= ~BIT(pl022
->cur_cs
);
467 tmp
|= BIT(pl022
->cur_cs
);
468 writew(tmp
, SSP_CSR(pl022
->virtbase
));
471 static void pl022_cs_control(struct pl022
*pl022
, u32 command
)
473 if (pl022
->vendor
->internal_cs_ctrl
)
474 internal_cs_control(pl022
, command
);
475 else if (gpio_is_valid(pl022
->cur_cs
))
476 gpio_set_value(pl022
->cur_cs
, command
);
478 pl022
->cur_chip
->cs_control(command
);
482 * giveback - current spi_message is over, schedule next message and call
483 * callback of this message. Assumes that caller already
484 * set message->status; dma and pio irqs are blocked
485 * @pl022: SSP driver private data structure
487 static void giveback(struct pl022
*pl022
)
489 struct spi_transfer
*last_transfer
;
490 pl022
->next_msg_cs_active
= false;
492 last_transfer
= list_last_entry(&pl022
->cur_msg
->transfers
,
493 struct spi_transfer
, transfer_list
);
495 /* Delay if requested before any change in chip select */
496 if (last_transfer
->delay_usecs
)
498 * FIXME: This runs in interrupt context.
499 * Is this really smart?
501 udelay(last_transfer
->delay_usecs
);
503 if (!last_transfer
->cs_change
) {
504 struct spi_message
*next_msg
;
507 * cs_change was not set. We can keep the chip select
508 * enabled if there is message in the queue and it is
509 * for the same spi device.
511 * We cannot postpone this until pump_messages, because
512 * after calling msg->complete (below) the driver that
513 * sent the current message could be unloaded, which
514 * could invalidate the cs_control() callback...
516 /* get a pointer to the next message, if any */
517 next_msg
= spi_get_next_queued_message(pl022
->master
);
520 * see if the next and current messages point
521 * to the same spi device.
523 if (next_msg
&& next_msg
->spi
!= pl022
->cur_msg
->spi
)
525 if (!next_msg
|| pl022
->cur_msg
->state
== STATE_ERROR
)
526 pl022_cs_control(pl022
, SSP_CHIP_DESELECT
);
528 pl022
->next_msg_cs_active
= true;
532 pl022
->cur_msg
= NULL
;
533 pl022
->cur_transfer
= NULL
;
534 pl022
->cur_chip
= NULL
;
536 /* disable the SPI/SSP operation */
537 writew((readw(SSP_CR1(pl022
->virtbase
)) &
538 (~SSP_CR1_MASK_SSE
)), SSP_CR1(pl022
->virtbase
));
540 spi_finalize_current_message(pl022
->master
);
544 * flush - flush the FIFO to reach a clean state
545 * @pl022: SSP driver private data structure
547 static int flush(struct pl022
*pl022
)
549 unsigned long limit
= loops_per_jiffy
<< 1;
551 dev_dbg(&pl022
->adev
->dev
, "flush\n");
553 while (readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_RNE
)
554 readw(SSP_DR(pl022
->virtbase
));
555 } while ((readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_BSY
) && limit
--);
557 pl022
->exp_fifo_level
= 0;
563 * restore_state - Load configuration of current chip
564 * @pl022: SSP driver private data structure
566 static void restore_state(struct pl022
*pl022
)
568 struct chip_data
*chip
= pl022
->cur_chip
;
570 if (pl022
->vendor
->extended_cr
)
571 writel(chip
->cr0
, SSP_CR0(pl022
->virtbase
));
573 writew(chip
->cr0
, SSP_CR0(pl022
->virtbase
));
574 writew(chip
->cr1
, SSP_CR1(pl022
->virtbase
));
575 writew(chip
->dmacr
, SSP_DMACR(pl022
->virtbase
));
576 writew(chip
->cpsr
, SSP_CPSR(pl022
->virtbase
));
577 writew(DISABLE_ALL_INTERRUPTS
, SSP_IMSC(pl022
->virtbase
));
578 writew(CLEAR_ALL_INTERRUPTS
, SSP_ICR(pl022
->virtbase
));
582 * Default SSP Register Values
584 #define DEFAULT_SSP_REG_CR0 ( \
585 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
586 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
587 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
588 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
589 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
592 /* ST versions have slightly different bit layout */
593 #define DEFAULT_SSP_REG_CR0_ST ( \
594 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
595 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
596 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
597 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
598 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
599 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
600 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
603 /* The PL023 version is slightly different again */
604 #define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
605 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
606 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
607 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
608 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
611 #define DEFAULT_SSP_REG_CR1 ( \
612 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
613 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
614 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
615 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
618 /* ST versions extend this register to use all 16 bits */
619 #define DEFAULT_SSP_REG_CR1_ST ( \
620 DEFAULT_SSP_REG_CR1 | \
621 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
622 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
623 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
624 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
625 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
629 * The PL023 variant has further differences: no loopback mode, no microwire
630 * support, and a new clock feedback delay setting.
632 #define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
633 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
634 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
635 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
636 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
637 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
638 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
639 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
640 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
643 #define DEFAULT_SSP_REG_CPSR ( \
644 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
647 #define DEFAULT_SSP_REG_DMACR (\
648 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
649 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
653 * load_ssp_default_config - Load default configuration for SSP
654 * @pl022: SSP driver private data structure
656 static void load_ssp_default_config(struct pl022
*pl022
)
658 if (pl022
->vendor
->pl023
) {
659 writel(DEFAULT_SSP_REG_CR0_ST_PL023
, SSP_CR0(pl022
->virtbase
));
660 writew(DEFAULT_SSP_REG_CR1_ST_PL023
, SSP_CR1(pl022
->virtbase
));
661 } else if (pl022
->vendor
->extended_cr
) {
662 writel(DEFAULT_SSP_REG_CR0_ST
, SSP_CR0(pl022
->virtbase
));
663 writew(DEFAULT_SSP_REG_CR1_ST
, SSP_CR1(pl022
->virtbase
));
665 writew(DEFAULT_SSP_REG_CR0
, SSP_CR0(pl022
->virtbase
));
666 writew(DEFAULT_SSP_REG_CR1
, SSP_CR1(pl022
->virtbase
));
668 writew(DEFAULT_SSP_REG_DMACR
, SSP_DMACR(pl022
->virtbase
));
669 writew(DEFAULT_SSP_REG_CPSR
, SSP_CPSR(pl022
->virtbase
));
670 writew(DISABLE_ALL_INTERRUPTS
, SSP_IMSC(pl022
->virtbase
));
671 writew(CLEAR_ALL_INTERRUPTS
, SSP_ICR(pl022
->virtbase
));
675 * This will write to TX and read from RX according to the parameters
678 static void readwriter(struct pl022
*pl022
)
682 * The FIFO depth is different between primecell variants.
683 * I believe filling in too much in the FIFO might cause
684 * errons in 8bit wide transfers on ARM variants (just 8 words
685 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
687 * To prevent this issue, the TX FIFO is only filled to the
688 * unused RX FIFO fill length, regardless of what the TX
689 * FIFO status flag indicates.
691 dev_dbg(&pl022
->adev
->dev
,
692 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
693 __func__
, pl022
->rx
, pl022
->rx_end
, pl022
->tx
, pl022
->tx_end
);
695 /* Read as much as you can */
696 while ((readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_RNE
)
697 && (pl022
->rx
< pl022
->rx_end
)) {
698 switch (pl022
->read
) {
700 readw(SSP_DR(pl022
->virtbase
));
703 *(u8
*) (pl022
->rx
) =
704 readw(SSP_DR(pl022
->virtbase
)) & 0xFFU
;
707 *(u16
*) (pl022
->rx
) =
708 (u16
) readw(SSP_DR(pl022
->virtbase
));
711 *(u32
*) (pl022
->rx
) =
712 readl(SSP_DR(pl022
->virtbase
));
715 pl022
->rx
+= (pl022
->cur_chip
->n_bytes
);
716 pl022
->exp_fifo_level
--;
719 * Write as much as possible up to the RX FIFO size
721 while ((pl022
->exp_fifo_level
< pl022
->vendor
->fifodepth
)
722 && (pl022
->tx
< pl022
->tx_end
)) {
723 switch (pl022
->write
) {
725 writew(0x0, SSP_DR(pl022
->virtbase
));
728 writew(*(u8
*) (pl022
->tx
), SSP_DR(pl022
->virtbase
));
731 writew((*(u16
*) (pl022
->tx
)), SSP_DR(pl022
->virtbase
));
734 writel(*(u32
*) (pl022
->tx
), SSP_DR(pl022
->virtbase
));
737 pl022
->tx
+= (pl022
->cur_chip
->n_bytes
);
738 pl022
->exp_fifo_level
++;
740 * This inner reader takes care of things appearing in the RX
741 * FIFO as we're transmitting. This will happen a lot since the
742 * clock starts running when you put things into the TX FIFO,
743 * and then things are continuously clocked into the RX FIFO.
745 while ((readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_RNE
)
746 && (pl022
->rx
< pl022
->rx_end
)) {
747 switch (pl022
->read
) {
749 readw(SSP_DR(pl022
->virtbase
));
752 *(u8
*) (pl022
->rx
) =
753 readw(SSP_DR(pl022
->virtbase
)) & 0xFFU
;
756 *(u16
*) (pl022
->rx
) =
757 (u16
) readw(SSP_DR(pl022
->virtbase
));
760 *(u32
*) (pl022
->rx
) =
761 readl(SSP_DR(pl022
->virtbase
));
764 pl022
->rx
+= (pl022
->cur_chip
->n_bytes
);
765 pl022
->exp_fifo_level
--;
769 * When we exit here the TX FIFO should be full and the RX FIFO
775 * next_transfer - Move to the Next transfer in the current spi message
776 * @pl022: SSP driver private data structure
778 * This function moves though the linked list of spi transfers in the
779 * current spi message and returns with the state of current spi
780 * message i.e whether its last transfer is done(STATE_DONE) or
781 * Next transfer is ready(STATE_RUNNING)
783 static void *next_transfer(struct pl022
*pl022
)
785 struct spi_message
*msg
= pl022
->cur_msg
;
786 struct spi_transfer
*trans
= pl022
->cur_transfer
;
788 /* Move to next transfer */
789 if (trans
->transfer_list
.next
!= &msg
->transfers
) {
790 pl022
->cur_transfer
=
791 list_entry(trans
->transfer_list
.next
,
792 struct spi_transfer
, transfer_list
);
793 return STATE_RUNNING
;
799 * This DMA functionality is only compiled in if we have
800 * access to the generic DMA devices/DMA engine.
802 #ifdef CONFIG_DMA_ENGINE
803 static void unmap_free_dma_scatter(struct pl022
*pl022
)
805 /* Unmap and free the SG tables */
806 dma_unmap_sg(pl022
->dma_tx_channel
->device
->dev
, pl022
->sgt_tx
.sgl
,
807 pl022
->sgt_tx
.nents
, DMA_TO_DEVICE
);
808 dma_unmap_sg(pl022
->dma_rx_channel
->device
->dev
, pl022
->sgt_rx
.sgl
,
809 pl022
->sgt_rx
.nents
, DMA_FROM_DEVICE
);
810 sg_free_table(&pl022
->sgt_rx
);
811 sg_free_table(&pl022
->sgt_tx
);
814 static void dma_callback(void *data
)
816 struct pl022
*pl022
= data
;
817 struct spi_message
*msg
= pl022
->cur_msg
;
819 BUG_ON(!pl022
->sgt_rx
.sgl
);
823 * Optionally dump out buffers to inspect contents, this is
824 * good if you want to convince yourself that the loopback
825 * read/write contents are the same, when adopting to a new
829 struct scatterlist
*sg
;
832 dma_sync_sg_for_cpu(&pl022
->adev
->dev
,
837 for_each_sg(pl022
->sgt_rx
.sgl
, sg
, pl022
->sgt_rx
.nents
, i
) {
838 dev_dbg(&pl022
->adev
->dev
, "SPI RX SG ENTRY: %d", i
);
839 print_hex_dump(KERN_ERR
, "SPI RX: ",
847 for_each_sg(pl022
->sgt_tx
.sgl
, sg
, pl022
->sgt_tx
.nents
, i
) {
848 dev_dbg(&pl022
->adev
->dev
, "SPI TX SG ENTRY: %d", i
);
849 print_hex_dump(KERN_ERR
, "SPI TX: ",
860 unmap_free_dma_scatter(pl022
);
862 /* Update total bytes transferred */
863 msg
->actual_length
+= pl022
->cur_transfer
->len
;
864 if (pl022
->cur_transfer
->cs_change
)
865 pl022_cs_control(pl022
, SSP_CHIP_DESELECT
);
867 /* Move to next transfer */
868 msg
->state
= next_transfer(pl022
);
869 tasklet_schedule(&pl022
->pump_transfers
);
872 static void setup_dma_scatter(struct pl022
*pl022
,
875 struct sg_table
*sgtab
)
877 struct scatterlist
*sg
;
878 int bytesleft
= length
;
884 for_each_sg(sgtab
->sgl
, sg
, sgtab
->nents
, i
) {
886 * If there are less bytes left than what fits
887 * in the current page (plus page alignment offset)
888 * we just feed in this, else we stuff in as much
891 if (bytesleft
< (PAGE_SIZE
- offset_in_page(bufp
)))
892 mapbytes
= bytesleft
;
894 mapbytes
= PAGE_SIZE
- offset_in_page(bufp
);
895 sg_set_page(sg
, virt_to_page(bufp
),
896 mapbytes
, offset_in_page(bufp
));
898 bytesleft
-= mapbytes
;
899 dev_dbg(&pl022
->adev
->dev
,
900 "set RX/TX target page @ %p, %d bytes, %d left\n",
901 bufp
, mapbytes
, bytesleft
);
904 /* Map the dummy buffer on every page */
905 for_each_sg(sgtab
->sgl
, sg
, sgtab
->nents
, i
) {
906 if (bytesleft
< PAGE_SIZE
)
907 mapbytes
= bytesleft
;
909 mapbytes
= PAGE_SIZE
;
910 sg_set_page(sg
, virt_to_page(pl022
->dummypage
),
912 bytesleft
-= mapbytes
;
913 dev_dbg(&pl022
->adev
->dev
,
914 "set RX/TX to dummy page %d bytes, %d left\n",
915 mapbytes
, bytesleft
);
923 * configure_dma - configures the channels for the next transfer
924 * @pl022: SSP driver's private data structure
926 static int configure_dma(struct pl022
*pl022
)
928 struct dma_slave_config rx_conf
= {
929 .src_addr
= SSP_DR(pl022
->phybase
),
930 .direction
= DMA_DEV_TO_MEM
,
933 struct dma_slave_config tx_conf
= {
934 .dst_addr
= SSP_DR(pl022
->phybase
),
935 .direction
= DMA_MEM_TO_DEV
,
940 int rx_sglen
, tx_sglen
;
941 struct dma_chan
*rxchan
= pl022
->dma_rx_channel
;
942 struct dma_chan
*txchan
= pl022
->dma_tx_channel
;
943 struct dma_async_tx_descriptor
*rxdesc
;
944 struct dma_async_tx_descriptor
*txdesc
;
946 /* Check that the channels are available */
947 if (!rxchan
|| !txchan
)
951 * If supplied, the DMA burstsize should equal the FIFO trigger level.
952 * Notice that the DMA engine uses one-to-one mapping. Since we can
953 * not trigger on 2 elements this needs explicit mapping rather than
956 switch (pl022
->rx_lev_trig
) {
957 case SSP_RX_1_OR_MORE_ELEM
:
958 rx_conf
.src_maxburst
= 1;
960 case SSP_RX_4_OR_MORE_ELEM
:
961 rx_conf
.src_maxburst
= 4;
963 case SSP_RX_8_OR_MORE_ELEM
:
964 rx_conf
.src_maxburst
= 8;
966 case SSP_RX_16_OR_MORE_ELEM
:
967 rx_conf
.src_maxburst
= 16;
969 case SSP_RX_32_OR_MORE_ELEM
:
970 rx_conf
.src_maxburst
= 32;
973 rx_conf
.src_maxburst
= pl022
->vendor
->fifodepth
>> 1;
977 switch (pl022
->tx_lev_trig
) {
978 case SSP_TX_1_OR_MORE_EMPTY_LOC
:
979 tx_conf
.dst_maxburst
= 1;
981 case SSP_TX_4_OR_MORE_EMPTY_LOC
:
982 tx_conf
.dst_maxburst
= 4;
984 case SSP_TX_8_OR_MORE_EMPTY_LOC
:
985 tx_conf
.dst_maxburst
= 8;
987 case SSP_TX_16_OR_MORE_EMPTY_LOC
:
988 tx_conf
.dst_maxburst
= 16;
990 case SSP_TX_32_OR_MORE_EMPTY_LOC
:
991 tx_conf
.dst_maxburst
= 32;
994 tx_conf
.dst_maxburst
= pl022
->vendor
->fifodepth
>> 1;
998 switch (pl022
->read
) {
1000 /* Use the same as for writing */
1001 rx_conf
.src_addr_width
= DMA_SLAVE_BUSWIDTH_UNDEFINED
;
1004 rx_conf
.src_addr_width
= DMA_SLAVE_BUSWIDTH_1_BYTE
;
1007 rx_conf
.src_addr_width
= DMA_SLAVE_BUSWIDTH_2_BYTES
;
1010 rx_conf
.src_addr_width
= DMA_SLAVE_BUSWIDTH_4_BYTES
;
1014 switch (pl022
->write
) {
1016 /* Use the same as for reading */
1017 tx_conf
.dst_addr_width
= DMA_SLAVE_BUSWIDTH_UNDEFINED
;
1020 tx_conf
.dst_addr_width
= DMA_SLAVE_BUSWIDTH_1_BYTE
;
1023 tx_conf
.dst_addr_width
= DMA_SLAVE_BUSWIDTH_2_BYTES
;
1026 tx_conf
.dst_addr_width
= DMA_SLAVE_BUSWIDTH_4_BYTES
;
1030 /* SPI pecularity: we need to read and write the same width */
1031 if (rx_conf
.src_addr_width
== DMA_SLAVE_BUSWIDTH_UNDEFINED
)
1032 rx_conf
.src_addr_width
= tx_conf
.dst_addr_width
;
1033 if (tx_conf
.dst_addr_width
== DMA_SLAVE_BUSWIDTH_UNDEFINED
)
1034 tx_conf
.dst_addr_width
= rx_conf
.src_addr_width
;
1035 BUG_ON(rx_conf
.src_addr_width
!= tx_conf
.dst_addr_width
);
1037 dmaengine_slave_config(rxchan
, &rx_conf
);
1038 dmaengine_slave_config(txchan
, &tx_conf
);
1040 /* Create sglists for the transfers */
1041 pages
= DIV_ROUND_UP(pl022
->cur_transfer
->len
, PAGE_SIZE
);
1042 dev_dbg(&pl022
->adev
->dev
, "using %d pages for transfer\n", pages
);
1044 ret
= sg_alloc_table(&pl022
->sgt_rx
, pages
, GFP_ATOMIC
);
1046 goto err_alloc_rx_sg
;
1048 ret
= sg_alloc_table(&pl022
->sgt_tx
, pages
, GFP_ATOMIC
);
1050 goto err_alloc_tx_sg
;
1052 /* Fill in the scatterlists for the RX+TX buffers */
1053 setup_dma_scatter(pl022
, pl022
->rx
,
1054 pl022
->cur_transfer
->len
, &pl022
->sgt_rx
);
1055 setup_dma_scatter(pl022
, pl022
->tx
,
1056 pl022
->cur_transfer
->len
, &pl022
->sgt_tx
);
1058 /* Map DMA buffers */
1059 rx_sglen
= dma_map_sg(rxchan
->device
->dev
, pl022
->sgt_rx
.sgl
,
1060 pl022
->sgt_rx
.nents
, DMA_FROM_DEVICE
);
1064 tx_sglen
= dma_map_sg(txchan
->device
->dev
, pl022
->sgt_tx
.sgl
,
1065 pl022
->sgt_tx
.nents
, DMA_TO_DEVICE
);
1069 /* Send both scatterlists */
1070 rxdesc
= dmaengine_prep_slave_sg(rxchan
,
1074 DMA_PREP_INTERRUPT
| DMA_CTRL_ACK
);
1078 txdesc
= dmaengine_prep_slave_sg(txchan
,
1082 DMA_PREP_INTERRUPT
| DMA_CTRL_ACK
);
1086 /* Put the callback on the RX transfer only, that should finish last */
1087 rxdesc
->callback
= dma_callback
;
1088 rxdesc
->callback_param
= pl022
;
1090 /* Submit and fire RX and TX with TX last so we're ready to read! */
1091 dmaengine_submit(rxdesc
);
1092 dmaengine_submit(txdesc
);
1093 dma_async_issue_pending(rxchan
);
1094 dma_async_issue_pending(txchan
);
1095 pl022
->dma_running
= true;
1100 dmaengine_terminate_all(txchan
);
1102 dmaengine_terminate_all(rxchan
);
1103 dma_unmap_sg(txchan
->device
->dev
, pl022
->sgt_tx
.sgl
,
1104 pl022
->sgt_tx
.nents
, DMA_TO_DEVICE
);
1106 dma_unmap_sg(rxchan
->device
->dev
, pl022
->sgt_rx
.sgl
,
1107 pl022
->sgt_rx
.nents
, DMA_FROM_DEVICE
);
1109 sg_free_table(&pl022
->sgt_tx
);
1111 sg_free_table(&pl022
->sgt_rx
);
1116 static int pl022_dma_probe(struct pl022
*pl022
)
1118 dma_cap_mask_t mask
;
1120 /* Try to acquire a generic DMA engine slave channel */
1122 dma_cap_set(DMA_SLAVE
, mask
);
1124 * We need both RX and TX channels to do DMA, else do none
1127 pl022
->dma_rx_channel
= dma_request_channel(mask
,
1128 pl022
->master_info
->dma_filter
,
1129 pl022
->master_info
->dma_rx_param
);
1130 if (!pl022
->dma_rx_channel
) {
1131 dev_dbg(&pl022
->adev
->dev
, "no RX DMA channel!\n");
1135 pl022
->dma_tx_channel
= dma_request_channel(mask
,
1136 pl022
->master_info
->dma_filter
,
1137 pl022
->master_info
->dma_tx_param
);
1138 if (!pl022
->dma_tx_channel
) {
1139 dev_dbg(&pl022
->adev
->dev
, "no TX DMA channel!\n");
1143 pl022
->dummypage
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
1144 if (!pl022
->dummypage
)
1145 goto err_no_dummypage
;
1147 dev_info(&pl022
->adev
->dev
, "setup for DMA on RX %s, TX %s\n",
1148 dma_chan_name(pl022
->dma_rx_channel
),
1149 dma_chan_name(pl022
->dma_tx_channel
));
1154 dma_release_channel(pl022
->dma_tx_channel
);
1156 dma_release_channel(pl022
->dma_rx_channel
);
1157 pl022
->dma_rx_channel
= NULL
;
1159 dev_err(&pl022
->adev
->dev
,
1160 "Failed to work in dma mode, work without dma!\n");
1164 static int pl022_dma_autoprobe(struct pl022
*pl022
)
1166 struct device
*dev
= &pl022
->adev
->dev
;
1167 struct dma_chan
*chan
;
1170 /* automatically configure DMA channels from platform, normally using DT */
1171 chan
= dma_request_slave_channel_reason(dev
, "rx");
1173 err
= PTR_ERR(chan
);
1177 pl022
->dma_rx_channel
= chan
;
1179 chan
= dma_request_slave_channel_reason(dev
, "tx");
1181 err
= PTR_ERR(chan
);
1185 pl022
->dma_tx_channel
= chan
;
1187 pl022
->dummypage
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
1188 if (!pl022
->dummypage
) {
1190 goto err_no_dummypage
;
1196 dma_release_channel(pl022
->dma_tx_channel
);
1197 pl022
->dma_tx_channel
= NULL
;
1199 dma_release_channel(pl022
->dma_rx_channel
);
1200 pl022
->dma_rx_channel
= NULL
;
1205 static void terminate_dma(struct pl022
*pl022
)
1207 struct dma_chan
*rxchan
= pl022
->dma_rx_channel
;
1208 struct dma_chan
*txchan
= pl022
->dma_tx_channel
;
1210 dmaengine_terminate_all(rxchan
);
1211 dmaengine_terminate_all(txchan
);
1212 unmap_free_dma_scatter(pl022
);
1213 pl022
->dma_running
= false;
1216 static void pl022_dma_remove(struct pl022
*pl022
)
1218 if (pl022
->dma_running
)
1219 terminate_dma(pl022
);
1220 if (pl022
->dma_tx_channel
)
1221 dma_release_channel(pl022
->dma_tx_channel
);
1222 if (pl022
->dma_rx_channel
)
1223 dma_release_channel(pl022
->dma_rx_channel
);
1224 kfree(pl022
->dummypage
);
1228 static inline int configure_dma(struct pl022
*pl022
)
1233 static inline int pl022_dma_autoprobe(struct pl022
*pl022
)
1238 static inline int pl022_dma_probe(struct pl022
*pl022
)
1243 static inline void pl022_dma_remove(struct pl022
*pl022
)
1249 * pl022_interrupt_handler - Interrupt handler for SSP controller
1251 * This function handles interrupts generated for an interrupt based transfer.
1252 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1253 * current message's state as STATE_ERROR and schedule the tasklet
1254 * pump_transfers which will do the postprocessing of the current message by
1255 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1256 * more data, and writes data in TX FIFO till it is not full. If we complete
1257 * the transfer we move to the next transfer and schedule the tasklet.
1259 static irqreturn_t
pl022_interrupt_handler(int irq
, void *dev_id
)
1261 struct pl022
*pl022
= dev_id
;
1262 struct spi_message
*msg
= pl022
->cur_msg
;
1265 if (unlikely(!msg
)) {
1266 dev_err(&pl022
->adev
->dev
,
1267 "bad message state in interrupt handler");
1272 /* Read the Interrupt Status Register */
1273 irq_status
= readw(SSP_MIS(pl022
->virtbase
));
1275 if (unlikely(!irq_status
))
1279 * This handles the FIFO interrupts, the timeout
1280 * interrupts are flatly ignored, they cannot be
1283 if (unlikely(irq_status
& SSP_MIS_MASK_RORMIS
)) {
1285 * Overrun interrupt - bail out since our Data has been
1288 dev_err(&pl022
->adev
->dev
, "FIFO overrun\n");
1289 if (readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_RFF
)
1290 dev_err(&pl022
->adev
->dev
,
1291 "RXFIFO is full\n");
1294 * Disable and clear interrupts, disable SSP,
1295 * mark message with bad status so it can be
1298 writew(DISABLE_ALL_INTERRUPTS
,
1299 SSP_IMSC(pl022
->virtbase
));
1300 writew(CLEAR_ALL_INTERRUPTS
, SSP_ICR(pl022
->virtbase
));
1301 writew((readw(SSP_CR1(pl022
->virtbase
)) &
1302 (~SSP_CR1_MASK_SSE
)), SSP_CR1(pl022
->virtbase
));
1303 msg
->state
= STATE_ERROR
;
1305 /* Schedule message queue handler */
1306 tasklet_schedule(&pl022
->pump_transfers
);
1312 if (pl022
->tx
== pl022
->tx_end
) {
1313 /* Disable Transmit interrupt, enable receive interrupt */
1314 writew((readw(SSP_IMSC(pl022
->virtbase
)) &
1315 ~SSP_IMSC_MASK_TXIM
) | SSP_IMSC_MASK_RXIM
,
1316 SSP_IMSC(pl022
->virtbase
));
1320 * Since all transactions must write as much as shall be read,
1321 * we can conclude the entire transaction once RX is complete.
1322 * At this point, all TX will always be finished.
1324 if (pl022
->rx
>= pl022
->rx_end
) {
1325 writew(DISABLE_ALL_INTERRUPTS
,
1326 SSP_IMSC(pl022
->virtbase
));
1327 writew(CLEAR_ALL_INTERRUPTS
, SSP_ICR(pl022
->virtbase
));
1328 if (unlikely(pl022
->rx
> pl022
->rx_end
)) {
1329 dev_warn(&pl022
->adev
->dev
, "read %u surplus "
1330 "bytes (did you request an odd "
1331 "number of bytes on a 16bit bus?)\n",
1332 (u32
) (pl022
->rx
- pl022
->rx_end
));
1334 /* Update total bytes transferred */
1335 msg
->actual_length
+= pl022
->cur_transfer
->len
;
1336 if (pl022
->cur_transfer
->cs_change
)
1337 pl022_cs_control(pl022
, SSP_CHIP_DESELECT
);
1338 /* Move to next transfer */
1339 msg
->state
= next_transfer(pl022
);
1340 tasklet_schedule(&pl022
->pump_transfers
);
1348 * This sets up the pointers to memory for the next message to
1349 * send out on the SPI bus.
1351 static int set_up_next_transfer(struct pl022
*pl022
,
1352 struct spi_transfer
*transfer
)
1356 /* Sanity check the message for this bus width */
1357 residue
= pl022
->cur_transfer
->len
% pl022
->cur_chip
->n_bytes
;
1358 if (unlikely(residue
!= 0)) {
1359 dev_err(&pl022
->adev
->dev
,
1360 "message of %u bytes to transmit but the current "
1361 "chip bus has a data width of %u bytes!\n",
1362 pl022
->cur_transfer
->len
,
1363 pl022
->cur_chip
->n_bytes
);
1364 dev_err(&pl022
->adev
->dev
, "skipping this message\n");
1367 pl022
->tx
= (void *)transfer
->tx_buf
;
1368 pl022
->tx_end
= pl022
->tx
+ pl022
->cur_transfer
->len
;
1369 pl022
->rx
= (void *)transfer
->rx_buf
;
1370 pl022
->rx_end
= pl022
->rx
+ pl022
->cur_transfer
->len
;
1372 pl022
->tx
? pl022
->cur_chip
->write
: WRITING_NULL
;
1373 pl022
->read
= pl022
->rx
? pl022
->cur_chip
->read
: READING_NULL
;
1378 * pump_transfers - Tasklet function which schedules next transfer
1379 * when running in interrupt or DMA transfer mode.
1380 * @data: SSP driver private data structure
1383 static void pump_transfers(unsigned long data
)
1385 struct pl022
*pl022
= (struct pl022
*) data
;
1386 struct spi_message
*message
= NULL
;
1387 struct spi_transfer
*transfer
= NULL
;
1388 struct spi_transfer
*previous
= NULL
;
1390 /* Get current state information */
1391 message
= pl022
->cur_msg
;
1392 transfer
= pl022
->cur_transfer
;
1394 /* Handle for abort */
1395 if (message
->state
== STATE_ERROR
) {
1396 message
->status
= -EIO
;
1401 /* Handle end of message */
1402 if (message
->state
== STATE_DONE
) {
1403 message
->status
= 0;
1408 /* Delay if requested at end of transfer before CS change */
1409 if (message
->state
== STATE_RUNNING
) {
1410 previous
= list_entry(transfer
->transfer_list
.prev
,
1411 struct spi_transfer
,
1413 if (previous
->delay_usecs
)
1415 * FIXME: This runs in interrupt context.
1416 * Is this really smart?
1418 udelay(previous
->delay_usecs
);
1420 /* Reselect chip select only if cs_change was requested */
1421 if (previous
->cs_change
)
1422 pl022_cs_control(pl022
, SSP_CHIP_SELECT
);
1425 message
->state
= STATE_RUNNING
;
1428 if (set_up_next_transfer(pl022
, transfer
)) {
1429 message
->state
= STATE_ERROR
;
1430 message
->status
= -EIO
;
1434 /* Flush the FIFOs and let's go! */
1437 if (pl022
->cur_chip
->enable_dma
) {
1438 if (configure_dma(pl022
)) {
1439 dev_dbg(&pl022
->adev
->dev
,
1440 "configuration of DMA failed, fall back to interrupt mode\n");
1441 goto err_config_dma
;
1447 /* enable all interrupts except RX */
1448 writew(ENABLE_ALL_INTERRUPTS
& ~SSP_IMSC_MASK_RXIM
, SSP_IMSC(pl022
->virtbase
));
1451 static void do_interrupt_dma_transfer(struct pl022
*pl022
)
1454 * Default is to enable all interrupts except RX -
1455 * this will be enabled once TX is complete
1457 u32 irqflags
= (u32
)(ENABLE_ALL_INTERRUPTS
& ~SSP_IMSC_MASK_RXIM
);
1459 /* Enable target chip, if not already active */
1460 if (!pl022
->next_msg_cs_active
)
1461 pl022_cs_control(pl022
, SSP_CHIP_SELECT
);
1463 if (set_up_next_transfer(pl022
, pl022
->cur_transfer
)) {
1465 pl022
->cur_msg
->state
= STATE_ERROR
;
1466 pl022
->cur_msg
->status
= -EIO
;
1470 /* If we're using DMA, set up DMA here */
1471 if (pl022
->cur_chip
->enable_dma
) {
1472 /* Configure DMA transfer */
1473 if (configure_dma(pl022
)) {
1474 dev_dbg(&pl022
->adev
->dev
,
1475 "configuration of DMA failed, fall back to interrupt mode\n");
1476 goto err_config_dma
;
1478 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1479 irqflags
= DISABLE_ALL_INTERRUPTS
;
1482 /* Enable SSP, turn on interrupts */
1483 writew((readw(SSP_CR1(pl022
->virtbase
)) | SSP_CR1_MASK_SSE
),
1484 SSP_CR1(pl022
->virtbase
));
1485 writew(irqflags
, SSP_IMSC(pl022
->virtbase
));
1488 static void do_polling_transfer(struct pl022
*pl022
)
1490 struct spi_message
*message
= NULL
;
1491 struct spi_transfer
*transfer
= NULL
;
1492 struct spi_transfer
*previous
= NULL
;
1493 struct chip_data
*chip
;
1494 unsigned long time
, timeout
;
1496 chip
= pl022
->cur_chip
;
1497 message
= pl022
->cur_msg
;
1499 while (message
->state
!= STATE_DONE
) {
1500 /* Handle for abort */
1501 if (message
->state
== STATE_ERROR
)
1503 transfer
= pl022
->cur_transfer
;
1505 /* Delay if requested at end of transfer */
1506 if (message
->state
== STATE_RUNNING
) {
1508 list_entry(transfer
->transfer_list
.prev
,
1509 struct spi_transfer
, transfer_list
);
1510 if (previous
->delay_usecs
)
1511 udelay(previous
->delay_usecs
);
1512 if (previous
->cs_change
)
1513 pl022_cs_control(pl022
, SSP_CHIP_SELECT
);
1516 message
->state
= STATE_RUNNING
;
1517 if (!pl022
->next_msg_cs_active
)
1518 pl022_cs_control(pl022
, SSP_CHIP_SELECT
);
1521 /* Configuration Changing Per Transfer */
1522 if (set_up_next_transfer(pl022
, transfer
)) {
1524 message
->state
= STATE_ERROR
;
1527 /* Flush FIFOs and enable SSP */
1529 writew((readw(SSP_CR1(pl022
->virtbase
)) | SSP_CR1_MASK_SSE
),
1530 SSP_CR1(pl022
->virtbase
));
1532 dev_dbg(&pl022
->adev
->dev
, "polling transfer ongoing ...\n");
1534 timeout
= jiffies
+ msecs_to_jiffies(SPI_POLLING_TIMEOUT
);
1535 while (pl022
->tx
< pl022
->tx_end
|| pl022
->rx
< pl022
->rx_end
) {
1538 if (time_after(time
, timeout
)) {
1539 dev_warn(&pl022
->adev
->dev
,
1540 "%s: timeout!\n", __func__
);
1541 message
->state
= STATE_ERROR
;
1547 /* Update total byte transferred */
1548 message
->actual_length
+= pl022
->cur_transfer
->len
;
1549 if (pl022
->cur_transfer
->cs_change
)
1550 pl022_cs_control(pl022
, SSP_CHIP_DESELECT
);
1551 /* Move to next transfer */
1552 message
->state
= next_transfer(pl022
);
1555 /* Handle end of message */
1556 if (message
->state
== STATE_DONE
)
1557 message
->status
= 0;
1559 message
->status
= -EIO
;
1565 static int pl022_transfer_one_message(struct spi_master
*master
,
1566 struct spi_message
*msg
)
1568 struct pl022
*pl022
= spi_master_get_devdata(master
);
1570 /* Initial message state */
1571 pl022
->cur_msg
= msg
;
1572 msg
->state
= STATE_START
;
1574 pl022
->cur_transfer
= list_entry(msg
->transfers
.next
,
1575 struct spi_transfer
, transfer_list
);
1577 /* Setup the SPI using the per chip configuration */
1578 pl022
->cur_chip
= spi_get_ctldata(msg
->spi
);
1579 pl022
->cur_cs
= pl022
->chipselects
[msg
->spi
->chip_select
];
1581 restore_state(pl022
);
1584 if (pl022
->cur_chip
->xfer_type
== POLLING_TRANSFER
)
1585 do_polling_transfer(pl022
);
1587 do_interrupt_dma_transfer(pl022
);
1592 static int pl022_unprepare_transfer_hardware(struct spi_master
*master
)
1594 struct pl022
*pl022
= spi_master_get_devdata(master
);
1596 /* nothing more to do - disable spi/ssp and power off */
1597 writew((readw(SSP_CR1(pl022
->virtbase
)) &
1598 (~SSP_CR1_MASK_SSE
)), SSP_CR1(pl022
->virtbase
));
1603 static int verify_controller_parameters(struct pl022
*pl022
,
1604 struct pl022_config_chip
const *chip_info
)
1606 if ((chip_info
->iface
< SSP_INTERFACE_MOTOROLA_SPI
)
1607 || (chip_info
->iface
> SSP_INTERFACE_UNIDIRECTIONAL
)) {
1608 dev_err(&pl022
->adev
->dev
,
1609 "interface is configured incorrectly\n");
1612 if ((chip_info
->iface
== SSP_INTERFACE_UNIDIRECTIONAL
) &&
1613 (!pl022
->vendor
->unidir
)) {
1614 dev_err(&pl022
->adev
->dev
,
1615 "unidirectional mode not supported in this "
1616 "hardware version\n");
1619 if ((chip_info
->hierarchy
!= SSP_MASTER
)
1620 && (chip_info
->hierarchy
!= SSP_SLAVE
)) {
1621 dev_err(&pl022
->adev
->dev
,
1622 "hierarchy is configured incorrectly\n");
1625 if ((chip_info
->com_mode
!= INTERRUPT_TRANSFER
)
1626 && (chip_info
->com_mode
!= DMA_TRANSFER
)
1627 && (chip_info
->com_mode
!= POLLING_TRANSFER
)) {
1628 dev_err(&pl022
->adev
->dev
,
1629 "Communication mode is configured incorrectly\n");
1632 switch (chip_info
->rx_lev_trig
) {
1633 case SSP_RX_1_OR_MORE_ELEM
:
1634 case SSP_RX_4_OR_MORE_ELEM
:
1635 case SSP_RX_8_OR_MORE_ELEM
:
1636 /* These are always OK, all variants can handle this */
1638 case SSP_RX_16_OR_MORE_ELEM
:
1639 if (pl022
->vendor
->fifodepth
< 16) {
1640 dev_err(&pl022
->adev
->dev
,
1641 "RX FIFO Trigger Level is configured incorrectly\n");
1645 case SSP_RX_32_OR_MORE_ELEM
:
1646 if (pl022
->vendor
->fifodepth
< 32) {
1647 dev_err(&pl022
->adev
->dev
,
1648 "RX FIFO Trigger Level is configured incorrectly\n");
1653 dev_err(&pl022
->adev
->dev
,
1654 "RX FIFO Trigger Level is configured incorrectly\n");
1657 switch (chip_info
->tx_lev_trig
) {
1658 case SSP_TX_1_OR_MORE_EMPTY_LOC
:
1659 case SSP_TX_4_OR_MORE_EMPTY_LOC
:
1660 case SSP_TX_8_OR_MORE_EMPTY_LOC
:
1661 /* These are always OK, all variants can handle this */
1663 case SSP_TX_16_OR_MORE_EMPTY_LOC
:
1664 if (pl022
->vendor
->fifodepth
< 16) {
1665 dev_err(&pl022
->adev
->dev
,
1666 "TX FIFO Trigger Level is configured incorrectly\n");
1670 case SSP_TX_32_OR_MORE_EMPTY_LOC
:
1671 if (pl022
->vendor
->fifodepth
< 32) {
1672 dev_err(&pl022
->adev
->dev
,
1673 "TX FIFO Trigger Level is configured incorrectly\n");
1678 dev_err(&pl022
->adev
->dev
,
1679 "TX FIFO Trigger Level is configured incorrectly\n");
1682 if (chip_info
->iface
== SSP_INTERFACE_NATIONAL_MICROWIRE
) {
1683 if ((chip_info
->ctrl_len
< SSP_BITS_4
)
1684 || (chip_info
->ctrl_len
> SSP_BITS_32
)) {
1685 dev_err(&pl022
->adev
->dev
,
1686 "CTRL LEN is configured incorrectly\n");
1689 if ((chip_info
->wait_state
!= SSP_MWIRE_WAIT_ZERO
)
1690 && (chip_info
->wait_state
!= SSP_MWIRE_WAIT_ONE
)) {
1691 dev_err(&pl022
->adev
->dev
,
1692 "Wait State is configured incorrectly\n");
1695 /* Half duplex is only available in the ST Micro version */
1696 if (pl022
->vendor
->extended_cr
) {
1697 if ((chip_info
->duplex
!=
1698 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX
)
1699 && (chip_info
->duplex
!=
1700 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX
)) {
1701 dev_err(&pl022
->adev
->dev
,
1702 "Microwire duplex mode is configured incorrectly\n");
1706 if (chip_info
->duplex
!= SSP_MICROWIRE_CHANNEL_FULL_DUPLEX
)
1707 dev_err(&pl022
->adev
->dev
,
1708 "Microwire half duplex mode requested,"
1709 " but this is only available in the"
1710 " ST version of PL022\n");
1717 static inline u32
spi_rate(u32 rate
, u16 cpsdvsr
, u16 scr
)
1719 return rate
/ (cpsdvsr
* (1 + scr
));
1722 static int calculate_effective_freq(struct pl022
*pl022
, int freq
, struct
1723 ssp_clock_params
* clk_freq
)
1725 /* Lets calculate the frequency parameters */
1726 u16 cpsdvsr
= CPSDVR_MIN
, scr
= SCR_MIN
;
1727 u32 rate
, max_tclk
, min_tclk
, best_freq
= 0, best_cpsdvsr
= 0,
1728 best_scr
= 0, tmp
, found
= 0;
1730 rate
= clk_get_rate(pl022
->clk
);
1731 /* cpsdvscr = 2 & scr 0 */
1732 max_tclk
= spi_rate(rate
, CPSDVR_MIN
, SCR_MIN
);
1733 /* cpsdvsr = 254 & scr = 255 */
1734 min_tclk
= spi_rate(rate
, CPSDVR_MAX
, SCR_MAX
);
1736 if (freq
> max_tclk
)
1737 dev_warn(&pl022
->adev
->dev
,
1738 "Max speed that can be programmed is %d Hz, you requested %d\n",
1741 if (freq
< min_tclk
) {
1742 dev_err(&pl022
->adev
->dev
,
1743 "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1749 * best_freq will give closest possible available rate (<= requested
1750 * freq) for all values of scr & cpsdvsr.
1752 while ((cpsdvsr
<= CPSDVR_MAX
) && !found
) {
1753 while (scr
<= SCR_MAX
) {
1754 tmp
= spi_rate(rate
, cpsdvsr
, scr
);
1757 /* we need lower freq */
1763 * If found exact value, mark found and break.
1764 * If found more closer value, update and break.
1766 if (tmp
> best_freq
) {
1768 best_cpsdvsr
= cpsdvsr
;
1775 * increased scr will give lower rates, which are not
1784 WARN(!best_freq
, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1787 clk_freq
->cpsdvsr
= (u8
) (best_cpsdvsr
& 0xFF);
1788 clk_freq
->scr
= (u8
) (best_scr
& 0xFF);
1789 dev_dbg(&pl022
->adev
->dev
,
1790 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1792 dev_dbg(&pl022
->adev
->dev
, "SSP cpsdvsr = %d, scr = %d\n",
1793 clk_freq
->cpsdvsr
, clk_freq
->scr
);
1799 * A piece of default chip info unless the platform
1802 static const struct pl022_config_chip pl022_default_chip_info
= {
1803 .com_mode
= POLLING_TRANSFER
,
1804 .iface
= SSP_INTERFACE_MOTOROLA_SPI
,
1805 .hierarchy
= SSP_SLAVE
,
1806 .slave_tx_disable
= DO_NOT_DRIVE_TX
,
1807 .rx_lev_trig
= SSP_RX_1_OR_MORE_ELEM
,
1808 .tx_lev_trig
= SSP_TX_1_OR_MORE_EMPTY_LOC
,
1809 .ctrl_len
= SSP_BITS_8
,
1810 .wait_state
= SSP_MWIRE_WAIT_ZERO
,
1811 .duplex
= SSP_MICROWIRE_CHANNEL_FULL_DUPLEX
,
1812 .cs_control
= null_cs_control
,
1816 * pl022_setup - setup function registered to SPI master framework
1817 * @spi: spi device which is requesting setup
1819 * This function is registered to the SPI framework for this SPI master
1820 * controller. If it is the first time when setup is called by this device,
1821 * this function will initialize the runtime state for this chip and save
1822 * the same in the device structure. Else it will update the runtime info
1823 * with the updated chip info. Nothing is really being written to the
1824 * controller hardware here, that is not done until the actual transfer
1827 static int pl022_setup(struct spi_device
*spi
)
1829 struct pl022_config_chip
const *chip_info
;
1830 struct pl022_config_chip chip_info_dt
;
1831 struct chip_data
*chip
;
1832 struct ssp_clock_params clk_freq
= { .cpsdvsr
= 0, .scr
= 0};
1834 struct pl022
*pl022
= spi_master_get_devdata(spi
->master
);
1835 unsigned int bits
= spi
->bits_per_word
;
1837 struct device_node
*np
= spi
->dev
.of_node
;
1839 if (!spi
->max_speed_hz
)
1842 /* Get controller_state if one is supplied */
1843 chip
= spi_get_ctldata(spi
);
1846 chip
= kzalloc(sizeof(struct chip_data
), GFP_KERNEL
);
1850 "allocated memory for controller's runtime state\n");
1853 /* Get controller data if one is supplied */
1854 chip_info
= spi
->controller_data
;
1856 if (chip_info
== NULL
) {
1858 chip_info_dt
= pl022_default_chip_info
;
1860 chip_info_dt
.hierarchy
= SSP_MASTER
;
1861 of_property_read_u32(np
, "pl022,interface",
1862 &chip_info_dt
.iface
);
1863 of_property_read_u32(np
, "pl022,com-mode",
1864 &chip_info_dt
.com_mode
);
1865 of_property_read_u32(np
, "pl022,rx-level-trig",
1866 &chip_info_dt
.rx_lev_trig
);
1867 of_property_read_u32(np
, "pl022,tx-level-trig",
1868 &chip_info_dt
.tx_lev_trig
);
1869 of_property_read_u32(np
, "pl022,ctrl-len",
1870 &chip_info_dt
.ctrl_len
);
1871 of_property_read_u32(np
, "pl022,wait-state",
1872 &chip_info_dt
.wait_state
);
1873 of_property_read_u32(np
, "pl022,duplex",
1874 &chip_info_dt
.duplex
);
1876 chip_info
= &chip_info_dt
;
1878 chip_info
= &pl022_default_chip_info
;
1879 /* spi_board_info.controller_data not is supplied */
1881 "using default controller_data settings\n");
1885 "using user supplied controller_data settings\n");
1888 * We can override with custom divisors, else we use the board
1891 if ((0 == chip_info
->clk_freq
.cpsdvsr
)
1892 && (0 == chip_info
->clk_freq
.scr
)) {
1893 status
= calculate_effective_freq(pl022
,
1897 goto err_config_params
;
1899 memcpy(&clk_freq
, &chip_info
->clk_freq
, sizeof(clk_freq
));
1900 if ((clk_freq
.cpsdvsr
% 2) != 0)
1902 clk_freq
.cpsdvsr
- 1;
1904 if ((clk_freq
.cpsdvsr
< CPSDVR_MIN
)
1905 || (clk_freq
.cpsdvsr
> CPSDVR_MAX
)) {
1908 "cpsdvsr is configured incorrectly\n");
1909 goto err_config_params
;
1912 status
= verify_controller_parameters(pl022
, chip_info
);
1914 dev_err(&spi
->dev
, "controller data is incorrect");
1915 goto err_config_params
;
1918 pl022
->rx_lev_trig
= chip_info
->rx_lev_trig
;
1919 pl022
->tx_lev_trig
= chip_info
->tx_lev_trig
;
1921 /* Now set controller state based on controller data */
1922 chip
->xfer_type
= chip_info
->com_mode
;
1923 if (!chip_info
->cs_control
) {
1924 chip
->cs_control
= null_cs_control
;
1925 if (!gpio_is_valid(pl022
->chipselects
[spi
->chip_select
]))
1927 "invalid chip select\n");
1929 chip
->cs_control
= chip_info
->cs_control
;
1931 /* Check bits per word with vendor specific range */
1932 if ((bits
<= 3) || (bits
> pl022
->vendor
->max_bpw
)) {
1934 dev_err(&spi
->dev
, "illegal data size for this controller!\n");
1935 dev_err(&spi
->dev
, "This controller can only handle 4 <= n <= %d bit words\n",
1936 pl022
->vendor
->max_bpw
);
1937 goto err_config_params
;
1938 } else if (bits
<= 8) {
1939 dev_dbg(&spi
->dev
, "4 <= n <=8 bits per word\n");
1941 chip
->read
= READING_U8
;
1942 chip
->write
= WRITING_U8
;
1943 } else if (bits
<= 16) {
1944 dev_dbg(&spi
->dev
, "9 <= n <= 16 bits per word\n");
1946 chip
->read
= READING_U16
;
1947 chip
->write
= WRITING_U16
;
1949 dev_dbg(&spi
->dev
, "17 <= n <= 32 bits per word\n");
1951 chip
->read
= READING_U32
;
1952 chip
->write
= WRITING_U32
;
1955 /* Now Initialize all register settings required for this chip */
1960 if ((chip_info
->com_mode
== DMA_TRANSFER
)
1961 && ((pl022
->master_info
)->enable_dma
)) {
1962 chip
->enable_dma
= true;
1963 dev_dbg(&spi
->dev
, "DMA mode set in controller state\n");
1964 SSP_WRITE_BITS(chip
->dmacr
, SSP_DMA_ENABLED
,
1965 SSP_DMACR_MASK_RXDMAE
, 0);
1966 SSP_WRITE_BITS(chip
->dmacr
, SSP_DMA_ENABLED
,
1967 SSP_DMACR_MASK_TXDMAE
, 1);
1969 chip
->enable_dma
= false;
1970 dev_dbg(&spi
->dev
, "DMA mode NOT set in controller state\n");
1971 SSP_WRITE_BITS(chip
->dmacr
, SSP_DMA_DISABLED
,
1972 SSP_DMACR_MASK_RXDMAE
, 0);
1973 SSP_WRITE_BITS(chip
->dmacr
, SSP_DMA_DISABLED
,
1974 SSP_DMACR_MASK_TXDMAE
, 1);
1977 chip
->cpsr
= clk_freq
.cpsdvsr
;
1979 /* Special setup for the ST micro extended control registers */
1980 if (pl022
->vendor
->extended_cr
) {
1983 if (pl022
->vendor
->pl023
) {
1984 /* These bits are only in the PL023 */
1985 SSP_WRITE_BITS(chip
->cr1
, chip_info
->clkdelay
,
1986 SSP_CR1_MASK_FBCLKDEL_ST
, 13);
1988 /* These bits are in the PL022 but not PL023 */
1989 SSP_WRITE_BITS(chip
->cr0
, chip_info
->duplex
,
1990 SSP_CR0_MASK_HALFDUP_ST
, 5);
1991 SSP_WRITE_BITS(chip
->cr0
, chip_info
->ctrl_len
,
1992 SSP_CR0_MASK_CSS_ST
, 16);
1993 SSP_WRITE_BITS(chip
->cr0
, chip_info
->iface
,
1994 SSP_CR0_MASK_FRF_ST
, 21);
1995 SSP_WRITE_BITS(chip
->cr1
, chip_info
->wait_state
,
1996 SSP_CR1_MASK_MWAIT_ST
, 6);
1998 SSP_WRITE_BITS(chip
->cr0
, bits
- 1,
1999 SSP_CR0_MASK_DSS_ST
, 0);
2001 if (spi
->mode
& SPI_LSB_FIRST
) {
2008 SSP_WRITE_BITS(chip
->cr1
, tmp
, SSP_CR1_MASK_RENDN_ST
, 4);
2009 SSP_WRITE_BITS(chip
->cr1
, etx
, SSP_CR1_MASK_TENDN_ST
, 5);
2010 SSP_WRITE_BITS(chip
->cr1
, chip_info
->rx_lev_trig
,
2011 SSP_CR1_MASK_RXIFLSEL_ST
, 7);
2012 SSP_WRITE_BITS(chip
->cr1
, chip_info
->tx_lev_trig
,
2013 SSP_CR1_MASK_TXIFLSEL_ST
, 10);
2015 SSP_WRITE_BITS(chip
->cr0
, bits
- 1,
2016 SSP_CR0_MASK_DSS
, 0);
2017 SSP_WRITE_BITS(chip
->cr0
, chip_info
->iface
,
2018 SSP_CR0_MASK_FRF
, 4);
2021 /* Stuff that is common for all versions */
2022 if (spi
->mode
& SPI_CPOL
)
2023 tmp
= SSP_CLK_POL_IDLE_HIGH
;
2025 tmp
= SSP_CLK_POL_IDLE_LOW
;
2026 SSP_WRITE_BITS(chip
->cr0
, tmp
, SSP_CR0_MASK_SPO
, 6);
2028 if (spi
->mode
& SPI_CPHA
)
2029 tmp
= SSP_CLK_SECOND_EDGE
;
2031 tmp
= SSP_CLK_FIRST_EDGE
;
2032 SSP_WRITE_BITS(chip
->cr0
, tmp
, SSP_CR0_MASK_SPH
, 7);
2034 SSP_WRITE_BITS(chip
->cr0
, clk_freq
.scr
, SSP_CR0_MASK_SCR
, 8);
2035 /* Loopback is available on all versions except PL023 */
2036 if (pl022
->vendor
->loopback
) {
2037 if (spi
->mode
& SPI_LOOP
)
2038 tmp
= LOOPBACK_ENABLED
;
2040 tmp
= LOOPBACK_DISABLED
;
2041 SSP_WRITE_BITS(chip
->cr1
, tmp
, SSP_CR1_MASK_LBM
, 0);
2043 SSP_WRITE_BITS(chip
->cr1
, SSP_DISABLED
, SSP_CR1_MASK_SSE
, 1);
2044 SSP_WRITE_BITS(chip
->cr1
, chip_info
->hierarchy
, SSP_CR1_MASK_MS
, 2);
2045 SSP_WRITE_BITS(chip
->cr1
, chip_info
->slave_tx_disable
, SSP_CR1_MASK_SOD
,
2048 /* Save controller_state */
2049 spi_set_ctldata(spi
, chip
);
2052 spi_set_ctldata(spi
, NULL
);
2058 * pl022_cleanup - cleanup function registered to SPI master framework
2059 * @spi: spi device which is requesting cleanup
2061 * This function is registered to the SPI framework for this SPI master
2062 * controller. It will free the runtime state of chip.
2064 static void pl022_cleanup(struct spi_device
*spi
)
2066 struct chip_data
*chip
= spi_get_ctldata(spi
);
2068 spi_set_ctldata(spi
, NULL
);
2072 static struct pl022_ssp_controller
*
2073 pl022_platform_data_dt_get(struct device
*dev
)
2075 struct device_node
*np
= dev
->of_node
;
2076 struct pl022_ssp_controller
*pd
;
2080 dev_err(dev
, "no dt node defined\n");
2084 pd
= devm_kzalloc(dev
, sizeof(struct pl022_ssp_controller
), GFP_KERNEL
);
2090 of_property_read_u32(np
, "num-cs", &tmp
);
2091 pd
->num_chipselect
= tmp
;
2092 of_property_read_u32(np
, "pl022,autosuspend-delay",
2093 &pd
->autosuspend_delay
);
2094 pd
->rt
= of_property_read_bool(np
, "pl022,rt");
2099 static int pl022_probe(struct amba_device
*adev
, const struct amba_id
*id
)
2101 struct device
*dev
= &adev
->dev
;
2102 struct pl022_ssp_controller
*platform_info
=
2103 dev_get_platdata(&adev
->dev
);
2104 struct spi_master
*master
;
2105 struct pl022
*pl022
= NULL
; /*Data for this driver */
2106 struct device_node
*np
= adev
->dev
.of_node
;
2107 int status
= 0, i
, num_cs
;
2109 dev_info(&adev
->dev
,
2110 "ARM PL022 driver, device ID: 0x%08x\n", adev
->periphid
);
2111 if (!platform_info
&& IS_ENABLED(CONFIG_OF
))
2112 platform_info
= pl022_platform_data_dt_get(dev
);
2114 if (!platform_info
) {
2115 dev_err(dev
, "probe: no platform data defined\n");
2119 if (platform_info
->num_chipselect
) {
2120 num_cs
= platform_info
->num_chipselect
;
2122 dev_err(dev
, "probe: no chip select defined\n");
2126 /* Allocate master with space for data */
2127 master
= spi_alloc_master(dev
, sizeof(struct pl022
));
2128 if (master
== NULL
) {
2129 dev_err(&adev
->dev
, "probe - cannot alloc SPI master\n");
2133 pl022
= spi_master_get_devdata(master
);
2134 pl022
->master
= master
;
2135 pl022
->master_info
= platform_info
;
2137 pl022
->vendor
= id
->data
;
2138 pl022
->chipselects
= devm_kzalloc(dev
, num_cs
* sizeof(int),
2140 if (!pl022
->chipselects
) {
2146 * Bus Number Which has been Assigned to this SSP controller
2149 master
->bus_num
= platform_info
->bus_id
;
2150 master
->num_chipselect
= num_cs
;
2151 master
->cleanup
= pl022_cleanup
;
2152 master
->setup
= pl022_setup
;
2153 master
->auto_runtime_pm
= true;
2154 master
->transfer_one_message
= pl022_transfer_one_message
;
2155 master
->unprepare_transfer_hardware
= pl022_unprepare_transfer_hardware
;
2156 master
->rt
= platform_info
->rt
;
2157 master
->dev
.of_node
= dev
->of_node
;
2159 if (platform_info
->num_chipselect
&& platform_info
->chipselects
) {
2160 for (i
= 0; i
< num_cs
; i
++)
2161 pl022
->chipselects
[i
] = platform_info
->chipselects
[i
];
2162 } else if (pl022
->vendor
->internal_cs_ctrl
) {
2163 for (i
= 0; i
< num_cs
; i
++)
2164 pl022
->chipselects
[i
] = i
;
2165 } else if (IS_ENABLED(CONFIG_OF
)) {
2166 for (i
= 0; i
< num_cs
; i
++) {
2167 int cs_gpio
= of_get_named_gpio(np
, "cs-gpios", i
);
2169 if (cs_gpio
== -EPROBE_DEFER
) {
2170 status
= -EPROBE_DEFER
;
2174 pl022
->chipselects
[i
] = cs_gpio
;
2176 if (gpio_is_valid(cs_gpio
)) {
2177 if (devm_gpio_request(dev
, cs_gpio
, "ssp-pl022"))
2179 "could not request %d gpio\n",
2181 else if (gpio_direction_output(cs_gpio
, 1))
2183 "could not set gpio %d as output\n",
2190 * Supports mode 0-3, loopback, and active low CS. Transfers are
2191 * always MS bit first on the original pl022.
2193 master
->mode_bits
= SPI_CPOL
| SPI_CPHA
| SPI_CS_HIGH
| SPI_LOOP
;
2194 if (pl022
->vendor
->extended_cr
)
2195 master
->mode_bits
|= SPI_LSB_FIRST
;
2197 dev_dbg(&adev
->dev
, "BUSNO: %d\n", master
->bus_num
);
2199 status
= amba_request_regions(adev
, NULL
);
2201 goto err_no_ioregion
;
2203 pl022
->phybase
= adev
->res
.start
;
2204 pl022
->virtbase
= devm_ioremap(dev
, adev
->res
.start
,
2205 resource_size(&adev
->res
));
2206 if (pl022
->virtbase
== NULL
) {
2208 goto err_no_ioremap
;
2210 dev_info(&adev
->dev
, "mapped registers from %pa to %p\n",
2211 &adev
->res
.start
, pl022
->virtbase
);
2213 pl022
->clk
= devm_clk_get(&adev
->dev
, NULL
);
2214 if (IS_ERR(pl022
->clk
)) {
2215 status
= PTR_ERR(pl022
->clk
);
2216 dev_err(&adev
->dev
, "could not retrieve SSP/SPI bus clock\n");
2220 status
= clk_prepare_enable(pl022
->clk
);
2222 dev_err(&adev
->dev
, "could not enable SSP/SPI bus clock\n");
2226 /* Initialize transfer pump */
2227 tasklet_init(&pl022
->pump_transfers
, pump_transfers
,
2228 (unsigned long)pl022
);
2231 writew((readw(SSP_CR1(pl022
->virtbase
)) & (~SSP_CR1_MASK_SSE
)),
2232 SSP_CR1(pl022
->virtbase
));
2233 load_ssp_default_config(pl022
);
2235 status
= devm_request_irq(dev
, adev
->irq
[0], pl022_interrupt_handler
,
2238 dev_err(&adev
->dev
, "probe - cannot get IRQ (%d)\n", status
);
2242 /* Get DMA channels, try autoconfiguration first */
2243 status
= pl022_dma_autoprobe(pl022
);
2244 if (status
== -EPROBE_DEFER
) {
2245 dev_dbg(dev
, "deferring probe to get DMA channel\n");
2249 /* If that failed, use channels from platform_info */
2251 platform_info
->enable_dma
= 1;
2252 else if (platform_info
->enable_dma
) {
2253 status
= pl022_dma_probe(pl022
);
2255 platform_info
->enable_dma
= 0;
2258 /* Register with the SPI framework */
2259 amba_set_drvdata(adev
, pl022
);
2260 status
= devm_spi_register_master(&adev
->dev
, master
);
2263 "probe - problem registering spi master\n");
2264 goto err_spi_register
;
2266 dev_dbg(dev
, "probe succeeded\n");
2268 /* let runtime pm put suspend */
2269 if (platform_info
->autosuspend_delay
> 0) {
2270 dev_info(&adev
->dev
,
2271 "will use autosuspend for runtime pm, delay %dms\n",
2272 platform_info
->autosuspend_delay
);
2273 pm_runtime_set_autosuspend_delay(dev
,
2274 platform_info
->autosuspend_delay
);
2275 pm_runtime_use_autosuspend(dev
);
2277 pm_runtime_put(dev
);
2282 if (platform_info
->enable_dma
)
2283 pl022_dma_remove(pl022
);
2285 clk_disable_unprepare(pl022
->clk
);
2289 amba_release_regions(adev
);
2293 spi_master_put(master
);
2298 pl022_remove(struct amba_device
*adev
)
2300 struct pl022
*pl022
= amba_get_drvdata(adev
);
2306 * undo pm_runtime_put() in probe. I assume that we're not
2307 * accessing the primecell here.
2309 pm_runtime_get_noresume(&adev
->dev
);
2311 load_ssp_default_config(pl022
);
2312 if (pl022
->master_info
->enable_dma
)
2313 pl022_dma_remove(pl022
);
2315 clk_disable_unprepare(pl022
->clk
);
2316 amba_release_regions(adev
);
2317 tasklet_disable(&pl022
->pump_transfers
);
2321 #ifdef CONFIG_PM_SLEEP
2322 static int pl022_suspend(struct device
*dev
)
2324 struct pl022
*pl022
= dev_get_drvdata(dev
);
2327 ret
= spi_master_suspend(pl022
->master
);
2329 dev_warn(dev
, "cannot suspend master\n");
2333 ret
= pm_runtime_force_suspend(dev
);
2335 spi_master_resume(pl022
->master
);
2339 pinctrl_pm_select_sleep_state(dev
);
2341 dev_dbg(dev
, "suspended\n");
2345 static int pl022_resume(struct device
*dev
)
2347 struct pl022
*pl022
= dev_get_drvdata(dev
);
2350 ret
= pm_runtime_force_resume(dev
);
2352 dev_err(dev
, "problem resuming\n");
2354 /* Start the queue running */
2355 ret
= spi_master_resume(pl022
->master
);
2357 dev_err(dev
, "problem starting queue (%d)\n", ret
);
2359 dev_dbg(dev
, "resumed\n");
2366 static int pl022_runtime_suspend(struct device
*dev
)
2368 struct pl022
*pl022
= dev_get_drvdata(dev
);
2370 clk_disable_unprepare(pl022
->clk
);
2371 pinctrl_pm_select_idle_state(dev
);
2376 static int pl022_runtime_resume(struct device
*dev
)
2378 struct pl022
*pl022
= dev_get_drvdata(dev
);
2380 pinctrl_pm_select_default_state(dev
);
2381 clk_prepare_enable(pl022
->clk
);
2387 static const struct dev_pm_ops pl022_dev_pm_ops
= {
2388 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend
, pl022_resume
)
2389 SET_RUNTIME_PM_OPS(pl022_runtime_suspend
, pl022_runtime_resume
, NULL
)
2392 static struct vendor_data vendor_arm
= {
2396 .extended_cr
= false,
2399 .internal_cs_ctrl
= false,
2402 static struct vendor_data vendor_st
= {
2406 .extended_cr
= true,
2409 .internal_cs_ctrl
= false,
2412 static struct vendor_data vendor_st_pl023
= {
2416 .extended_cr
= true,
2419 .internal_cs_ctrl
= false,
2422 static struct vendor_data vendor_lsi
= {
2426 .extended_cr
= false,
2429 .internal_cs_ctrl
= true,
2432 static const struct amba_id pl022_ids
[] = {
2435 * ARM PL022 variant, this has a 16bit wide
2436 * and 8 locations deep TX/RX FIFO
2440 .data
= &vendor_arm
,
2444 * ST Micro derivative, this has 32bit wide
2445 * and 32 locations deep TX/RX FIFO
2453 * ST-Ericsson derivative "PL023" (this is not
2454 * an official ARM number), this is a PL022 SSP block
2455 * stripped to SPI mode only, it has 32bit wide
2456 * and 32 locations deep TX/RX FIFO but no extended
2461 .data
= &vendor_st_pl023
,
2465 * PL022 variant that has a chip select control register whih
2466 * allows control of 5 output signals nCS[0:4].
2470 .data
= &vendor_lsi
,
2475 MODULE_DEVICE_TABLE(amba
, pl022_ids
);
2477 static struct amba_driver pl022_driver
= {
2479 .name
= "ssp-pl022",
2480 .pm
= &pl022_dev_pm_ops
,
2482 .id_table
= pl022_ids
,
2483 .probe
= pl022_probe
,
2484 .remove
= pl022_remove
,
2487 static int __init
pl022_init(void)
2489 return amba_driver_register(&pl022_driver
);
2491 subsys_initcall(pl022_init
);
2493 static void __exit
pl022_exit(void)
2495 amba_driver_unregister(&pl022_driver
);
2497 module_exit(pl022_exit
);
2499 MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2500 MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2501 MODULE_LICENSE("GPL");