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_ITCR(r) (r + 0x080)
86 #define SSP_ITIP(r) (r + 0x084)
87 #define SSP_ITOP(r) (r + 0x088)
88 #define SSP_TDR(r) (r + 0x08C)
90 #define SSP_PID0(r) (r + 0xFE0)
91 #define SSP_PID1(r) (r + 0xFE4)
92 #define SSP_PID2(r) (r + 0xFE8)
93 #define SSP_PID3(r) (r + 0xFEC)
95 #define SSP_CID0(r) (r + 0xFF0)
96 #define SSP_CID1(r) (r + 0xFF4)
97 #define SSP_CID2(r) (r + 0xFF8)
98 #define SSP_CID3(r) (r + 0xFFC)
101 * SSP Control Register 0 - SSP_CR0
103 #define SSP_CR0_MASK_DSS (0x0FUL << 0)
104 #define SSP_CR0_MASK_FRF (0x3UL << 4)
105 #define SSP_CR0_MASK_SPO (0x1UL << 6)
106 #define SSP_CR0_MASK_SPH (0x1UL << 7)
107 #define SSP_CR0_MASK_SCR (0xFFUL << 8)
110 * The ST version of this block moves som bits
111 * in SSP_CR0 and extends it to 32 bits
113 #define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
114 #define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
115 #define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
116 #define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
119 * SSP Control Register 0 - SSP_CR1
121 #define SSP_CR1_MASK_LBM (0x1UL << 0)
122 #define SSP_CR1_MASK_SSE (0x1UL << 1)
123 #define SSP_CR1_MASK_MS (0x1UL << 2)
124 #define SSP_CR1_MASK_SOD (0x1UL << 3)
127 * The ST version of this block adds some bits
130 #define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
131 #define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
132 #define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
133 #define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
134 #define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
135 /* This one is only in the PL023 variant */
136 #define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
139 * SSP Status Register - SSP_SR
141 #define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
142 #define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
143 #define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
144 #define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
145 #define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
148 * SSP Clock Prescale Register - SSP_CPSR
150 #define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
153 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
155 #define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
156 #define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
157 #define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
158 #define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
161 * SSP Raw Interrupt Status Register - SSP_RIS
163 /* Receive Overrun Raw Interrupt status */
164 #define SSP_RIS_MASK_RORRIS (0x1UL << 0)
165 /* Receive Timeout Raw Interrupt status */
166 #define SSP_RIS_MASK_RTRIS (0x1UL << 1)
167 /* Receive FIFO Raw Interrupt status */
168 #define SSP_RIS_MASK_RXRIS (0x1UL << 2)
169 /* Transmit FIFO Raw Interrupt status */
170 #define SSP_RIS_MASK_TXRIS (0x1UL << 3)
173 * SSP Masked Interrupt Status Register - SSP_MIS
175 /* Receive Overrun Masked Interrupt status */
176 #define SSP_MIS_MASK_RORMIS (0x1UL << 0)
177 /* Receive Timeout Masked Interrupt status */
178 #define SSP_MIS_MASK_RTMIS (0x1UL << 1)
179 /* Receive FIFO Masked Interrupt status */
180 #define SSP_MIS_MASK_RXMIS (0x1UL << 2)
181 /* Transmit FIFO Masked Interrupt status */
182 #define SSP_MIS_MASK_TXMIS (0x1UL << 3)
185 * SSP Interrupt Clear Register - SSP_ICR
187 /* Receive Overrun Raw Clear Interrupt bit */
188 #define SSP_ICR_MASK_RORIC (0x1UL << 0)
189 /* Receive Timeout Clear Interrupt bit */
190 #define SSP_ICR_MASK_RTIC (0x1UL << 1)
193 * SSP DMA Control Register - SSP_DMACR
195 /* Receive DMA Enable bit */
196 #define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
197 /* Transmit DMA Enable bit */
198 #define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
201 * SSP Integration Test control Register - SSP_ITCR
203 #define SSP_ITCR_MASK_ITEN (0x1UL << 0)
204 #define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
207 * SSP Integration Test Input Register - SSP_ITIP
209 #define ITIP_MASK_SSPRXD (0x1UL << 0)
210 #define ITIP_MASK_SSPFSSIN (0x1UL << 1)
211 #define ITIP_MASK_SSPCLKIN (0x1UL << 2)
212 #define ITIP_MASK_RXDMAC (0x1UL << 3)
213 #define ITIP_MASK_TXDMAC (0x1UL << 4)
214 #define ITIP_MASK_SSPTXDIN (0x1UL << 5)
217 * SSP Integration Test output Register - SSP_ITOP
219 #define ITOP_MASK_SSPTXD (0x1UL << 0)
220 #define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
221 #define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
222 #define ITOP_MASK_SSPOEn (0x1UL << 3)
223 #define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
224 #define ITOP_MASK_RORINTR (0x1UL << 5)
225 #define ITOP_MASK_RTINTR (0x1UL << 6)
226 #define ITOP_MASK_RXINTR (0x1UL << 7)
227 #define ITOP_MASK_TXINTR (0x1UL << 8)
228 #define ITOP_MASK_INTR (0x1UL << 9)
229 #define ITOP_MASK_RXDMABREQ (0x1UL << 10)
230 #define ITOP_MASK_RXDMASREQ (0x1UL << 11)
231 #define ITOP_MASK_TXDMABREQ (0x1UL << 12)
232 #define ITOP_MASK_TXDMASREQ (0x1UL << 13)
235 * SSP Test Data Register - SSP_TDR
237 #define TDR_MASK_TESTDATA (0xFFFFFFFF)
241 * we use the spi_message.state (void *) pointer to
242 * hold a single state value, that's why all this
243 * (void *) casting is done here.
245 #define STATE_START ((void *) 0)
246 #define STATE_RUNNING ((void *) 1)
247 #define STATE_DONE ((void *) 2)
248 #define STATE_ERROR ((void *) -1)
251 * SSP State - Whether Enabled or Disabled
253 #define SSP_DISABLED (0)
254 #define SSP_ENABLED (1)
257 * SSP DMA State - Whether DMA Enabled or Disabled
259 #define SSP_DMA_DISABLED (0)
260 #define SSP_DMA_ENABLED (1)
265 #define SSP_DEFAULT_CLKRATE 0x2
266 #define SSP_DEFAULT_PRESCALE 0x40
269 * SSP Clock Parameter ranges
271 #define CPSDVR_MIN 0x02
272 #define CPSDVR_MAX 0xFE
277 * SSP Interrupt related Macros
279 #define DEFAULT_SSP_REG_IMSC 0x0UL
280 #define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
281 #define ENABLE_ALL_INTERRUPTS (~DEFAULT_SSP_REG_IMSC)
283 #define CLEAR_ALL_INTERRUPTS 0x3
285 #define SPI_POLLING_TIMEOUT 1000
288 * The type of reading going on on this chip
298 * The type of writing going on on this chip
308 * struct vendor_data - vendor-specific config parameters
309 * for PL022 derivates
310 * @fifodepth: depth of FIFOs (both)
311 * @max_bpw: maximum number of bits per word
312 * @unidir: supports unidirection transfers
313 * @extended_cr: 32 bit wide control register 0 with extra
314 * features and extra features in CR1 as found in the ST variants
315 * @pl023: supports a subset of the ST extensions called "PL023"
327 * struct pl022 - This is the private SSP driver data structure
328 * @adev: AMBA device model hookup
329 * @vendor: vendor data for the IP block
330 * @phybase: the physical memory where the SSP device resides
331 * @virtbase: the virtual memory where the SSP is mapped
332 * @clk: outgoing clock "SPICLK" for the SPI bus
333 * @master: SPI framework hookup
334 * @master_info: controller-specific data from machine setup
335 * @kworker: thread struct for message pump
336 * @kworker_task: pointer to task for message pump kworker thread
337 * @pump_messages: work struct for scheduling work to the message pump
338 * @queue_lock: spinlock to syncronise access to message queue
339 * @queue: message queue
340 * @busy: message pump is busy
341 * @running: message pump is running
342 * @pump_transfers: Tasklet used in Interrupt Transfer mode
343 * @cur_msg: Pointer to current spi_message being processed
344 * @cur_transfer: Pointer to current spi_transfer
345 * @cur_chip: pointer to current clients chip(assigned from controller_state)
346 * @next_msg_cs_active: the next message in the queue has been examined
347 * and it was found that it uses the same chip select as the previous
348 * message, so we left it active after the previous transfer, and it's
350 * @tx: current position in TX buffer to be read
351 * @tx_end: end position in TX buffer to be read
352 * @rx: current position in RX buffer to be written
353 * @rx_end: end position in RX buffer to be written
354 * @read: the type of read currently going on
355 * @write: the type of write currently going on
356 * @exp_fifo_level: expected FIFO level
357 * @dma_rx_channel: optional channel for RX DMA
358 * @dma_tx_channel: optional channel for TX DMA
359 * @sgt_rx: scattertable for the RX transfer
360 * @sgt_tx: scattertable for the TX transfer
361 * @dummypage: a dummy page used for driving data on the bus with DMA
362 * @cur_cs: current chip select (gpio)
363 * @chipselects: list of chipselects (gpios)
366 struct amba_device
*adev
;
367 struct vendor_data
*vendor
;
368 resource_size_t phybase
;
369 void __iomem
*virtbase
;
371 /* Two optional pin states - default & sleep */
372 struct pinctrl
*pinctrl
;
373 struct pinctrl_state
*pins_default
;
374 struct pinctrl_state
*pins_sleep
;
375 struct spi_master
*master
;
376 struct pl022_ssp_controller
*master_info
;
377 /* Message per-transfer pump */
378 struct tasklet_struct pump_transfers
;
379 struct spi_message
*cur_msg
;
380 struct spi_transfer
*cur_transfer
;
381 struct chip_data
*cur_chip
;
382 bool next_msg_cs_active
;
387 enum ssp_reading read
;
388 enum ssp_writing write
;
390 enum ssp_rx_level_trig rx_lev_trig
;
391 enum ssp_tx_level_trig tx_lev_trig
;
393 #ifdef CONFIG_DMA_ENGINE
394 struct dma_chan
*dma_rx_channel
;
395 struct dma_chan
*dma_tx_channel
;
396 struct sg_table sgt_rx
;
397 struct sg_table sgt_tx
;
406 * struct chip_data - To maintain runtime state of SSP for each client chip
407 * @cr0: Value of control register CR0 of SSP - on later ST variants this
408 * register is 32 bits wide rather than just 16
409 * @cr1: Value of control register CR1 of SSP
410 * @dmacr: Value of DMA control Register of SSP
411 * @cpsr: Value of Clock prescale register
412 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
413 * @enable_dma: Whether to enable DMA or not
414 * @read: function ptr to be used to read when doing xfer for this chip
415 * @write: function ptr to be used to write when doing xfer for this chip
416 * @cs_control: chip select callback provided by chip
417 * @xfer_type: polling/interrupt/DMA
419 * Runtime state of the SSP controller, maintained per chip,
420 * This would be set according to the current message that would be served
429 enum ssp_reading read
;
430 enum ssp_writing write
;
431 void (*cs_control
) (u32 command
);
436 * null_cs_control - Dummy chip select function
437 * @command: select/delect the chip
439 * If no chip select function is provided by client this is used as dummy
442 static void null_cs_control(u32 command
)
444 pr_debug("pl022: dummy chip select control, CS=0x%x\n", command
);
447 static void pl022_cs_control(struct pl022
*pl022
, u32 command
)
449 if (gpio_is_valid(pl022
->cur_cs
))
450 gpio_set_value(pl022
->cur_cs
, command
);
452 pl022
->cur_chip
->cs_control(command
);
456 * giveback - current spi_message is over, schedule next message and call
457 * callback of this message. Assumes that caller already
458 * set message->status; dma and pio irqs are blocked
459 * @pl022: SSP driver private data structure
461 static void giveback(struct pl022
*pl022
)
463 struct spi_transfer
*last_transfer
;
464 pl022
->next_msg_cs_active
= false;
466 last_transfer
= list_entry(pl022
->cur_msg
->transfers
.prev
,
470 /* Delay if requested before any change in chip select */
471 if (last_transfer
->delay_usecs
)
473 * FIXME: This runs in interrupt context.
474 * Is this really smart?
476 udelay(last_transfer
->delay_usecs
);
478 if (!last_transfer
->cs_change
) {
479 struct spi_message
*next_msg
;
482 * cs_change was not set. We can keep the chip select
483 * enabled if there is message in the queue and it is
484 * for the same spi device.
486 * We cannot postpone this until pump_messages, because
487 * after calling msg->complete (below) the driver that
488 * sent the current message could be unloaded, which
489 * could invalidate the cs_control() callback...
491 /* get a pointer to the next message, if any */
492 next_msg
= spi_get_next_queued_message(pl022
->master
);
495 * see if the next and current messages point
496 * to the same spi device.
498 if (next_msg
&& next_msg
->spi
!= pl022
->cur_msg
->spi
)
500 if (!next_msg
|| pl022
->cur_msg
->state
== STATE_ERROR
)
501 pl022_cs_control(pl022
, SSP_CHIP_DESELECT
);
503 pl022
->next_msg_cs_active
= true;
507 pl022
->cur_msg
= NULL
;
508 pl022
->cur_transfer
= NULL
;
509 pl022
->cur_chip
= NULL
;
510 spi_finalize_current_message(pl022
->master
);
512 /* disable the SPI/SSP operation */
513 writew((readw(SSP_CR1(pl022
->virtbase
)) &
514 (~SSP_CR1_MASK_SSE
)), SSP_CR1(pl022
->virtbase
));
519 * flush - flush the FIFO to reach a clean state
520 * @pl022: SSP driver private data structure
522 static int flush(struct pl022
*pl022
)
524 unsigned long limit
= loops_per_jiffy
<< 1;
526 dev_dbg(&pl022
->adev
->dev
, "flush\n");
528 while (readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_RNE
)
529 readw(SSP_DR(pl022
->virtbase
));
530 } while ((readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_BSY
) && limit
--);
532 pl022
->exp_fifo_level
= 0;
538 * restore_state - Load configuration of current chip
539 * @pl022: SSP driver private data structure
541 static void restore_state(struct pl022
*pl022
)
543 struct chip_data
*chip
= pl022
->cur_chip
;
545 if (pl022
->vendor
->extended_cr
)
546 writel(chip
->cr0
, SSP_CR0(pl022
->virtbase
));
548 writew(chip
->cr0
, SSP_CR0(pl022
->virtbase
));
549 writew(chip
->cr1
, SSP_CR1(pl022
->virtbase
));
550 writew(chip
->dmacr
, SSP_DMACR(pl022
->virtbase
));
551 writew(chip
->cpsr
, SSP_CPSR(pl022
->virtbase
));
552 writew(DISABLE_ALL_INTERRUPTS
, SSP_IMSC(pl022
->virtbase
));
553 writew(CLEAR_ALL_INTERRUPTS
, SSP_ICR(pl022
->virtbase
));
557 * Default SSP Register Values
559 #define DEFAULT_SSP_REG_CR0 ( \
560 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
561 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
562 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
563 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
564 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
567 /* ST versions have slightly different bit layout */
568 #define DEFAULT_SSP_REG_CR0_ST ( \
569 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
570 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
571 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
572 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
573 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
574 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
575 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
578 /* The PL023 version is slightly different again */
579 #define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
580 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
581 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
582 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
583 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
586 #define DEFAULT_SSP_REG_CR1 ( \
587 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
588 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
589 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
590 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
593 /* ST versions extend this register to use all 16 bits */
594 #define DEFAULT_SSP_REG_CR1_ST ( \
595 DEFAULT_SSP_REG_CR1 | \
596 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
597 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
598 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
599 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
600 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
604 * The PL023 variant has further differences: no loopback mode, no microwire
605 * support, and a new clock feedback delay setting.
607 #define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
608 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
609 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
610 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
611 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
612 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
613 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
614 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
615 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
618 #define DEFAULT_SSP_REG_CPSR ( \
619 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
622 #define DEFAULT_SSP_REG_DMACR (\
623 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
624 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
628 * load_ssp_default_config - Load default configuration for SSP
629 * @pl022: SSP driver private data structure
631 static void load_ssp_default_config(struct pl022
*pl022
)
633 if (pl022
->vendor
->pl023
) {
634 writel(DEFAULT_SSP_REG_CR0_ST_PL023
, SSP_CR0(pl022
->virtbase
));
635 writew(DEFAULT_SSP_REG_CR1_ST_PL023
, SSP_CR1(pl022
->virtbase
));
636 } else if (pl022
->vendor
->extended_cr
) {
637 writel(DEFAULT_SSP_REG_CR0_ST
, SSP_CR0(pl022
->virtbase
));
638 writew(DEFAULT_SSP_REG_CR1_ST
, SSP_CR1(pl022
->virtbase
));
640 writew(DEFAULT_SSP_REG_CR0
, SSP_CR0(pl022
->virtbase
));
641 writew(DEFAULT_SSP_REG_CR1
, SSP_CR1(pl022
->virtbase
));
643 writew(DEFAULT_SSP_REG_DMACR
, SSP_DMACR(pl022
->virtbase
));
644 writew(DEFAULT_SSP_REG_CPSR
, SSP_CPSR(pl022
->virtbase
));
645 writew(DISABLE_ALL_INTERRUPTS
, SSP_IMSC(pl022
->virtbase
));
646 writew(CLEAR_ALL_INTERRUPTS
, SSP_ICR(pl022
->virtbase
));
650 * This will write to TX and read from RX according to the parameters
653 static void readwriter(struct pl022
*pl022
)
657 * The FIFO depth is different between primecell variants.
658 * I believe filling in too much in the FIFO might cause
659 * errons in 8bit wide transfers on ARM variants (just 8 words
660 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
662 * To prevent this issue, the TX FIFO is only filled to the
663 * unused RX FIFO fill length, regardless of what the TX
664 * FIFO status flag indicates.
666 dev_dbg(&pl022
->adev
->dev
,
667 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
668 __func__
, pl022
->rx
, pl022
->rx_end
, pl022
->tx
, pl022
->tx_end
);
670 /* Read as much as you can */
671 while ((readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_RNE
)
672 && (pl022
->rx
< pl022
->rx_end
)) {
673 switch (pl022
->read
) {
675 readw(SSP_DR(pl022
->virtbase
));
678 *(u8
*) (pl022
->rx
) =
679 readw(SSP_DR(pl022
->virtbase
)) & 0xFFU
;
682 *(u16
*) (pl022
->rx
) =
683 (u16
) readw(SSP_DR(pl022
->virtbase
));
686 *(u32
*) (pl022
->rx
) =
687 readl(SSP_DR(pl022
->virtbase
));
690 pl022
->rx
+= (pl022
->cur_chip
->n_bytes
);
691 pl022
->exp_fifo_level
--;
694 * Write as much as possible up to the RX FIFO size
696 while ((pl022
->exp_fifo_level
< pl022
->vendor
->fifodepth
)
697 && (pl022
->tx
< pl022
->tx_end
)) {
698 switch (pl022
->write
) {
700 writew(0x0, SSP_DR(pl022
->virtbase
));
703 writew(*(u8
*) (pl022
->tx
), SSP_DR(pl022
->virtbase
));
706 writew((*(u16
*) (pl022
->tx
)), SSP_DR(pl022
->virtbase
));
709 writel(*(u32
*) (pl022
->tx
), SSP_DR(pl022
->virtbase
));
712 pl022
->tx
+= (pl022
->cur_chip
->n_bytes
);
713 pl022
->exp_fifo_level
++;
715 * This inner reader takes care of things appearing in the RX
716 * FIFO as we're transmitting. This will happen a lot since the
717 * clock starts running when you put things into the TX FIFO,
718 * and then things are continuously clocked into the RX FIFO.
720 while ((readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_RNE
)
721 && (pl022
->rx
< pl022
->rx_end
)) {
722 switch (pl022
->read
) {
724 readw(SSP_DR(pl022
->virtbase
));
727 *(u8
*) (pl022
->rx
) =
728 readw(SSP_DR(pl022
->virtbase
)) & 0xFFU
;
731 *(u16
*) (pl022
->rx
) =
732 (u16
) readw(SSP_DR(pl022
->virtbase
));
735 *(u32
*) (pl022
->rx
) =
736 readl(SSP_DR(pl022
->virtbase
));
739 pl022
->rx
+= (pl022
->cur_chip
->n_bytes
);
740 pl022
->exp_fifo_level
--;
744 * When we exit here the TX FIFO should be full and the RX FIFO
750 * next_transfer - Move to the Next transfer in the current spi message
751 * @pl022: SSP driver private data structure
753 * This function moves though the linked list of spi transfers in the
754 * current spi message and returns with the state of current spi
755 * message i.e whether its last transfer is done(STATE_DONE) or
756 * Next transfer is ready(STATE_RUNNING)
758 static void *next_transfer(struct pl022
*pl022
)
760 struct spi_message
*msg
= pl022
->cur_msg
;
761 struct spi_transfer
*trans
= pl022
->cur_transfer
;
763 /* Move to next transfer */
764 if (trans
->transfer_list
.next
!= &msg
->transfers
) {
765 pl022
->cur_transfer
=
766 list_entry(trans
->transfer_list
.next
,
767 struct spi_transfer
, transfer_list
);
768 return STATE_RUNNING
;
774 * This DMA functionality is only compiled in if we have
775 * access to the generic DMA devices/DMA engine.
777 #ifdef CONFIG_DMA_ENGINE
778 static void unmap_free_dma_scatter(struct pl022
*pl022
)
780 /* Unmap and free the SG tables */
781 dma_unmap_sg(pl022
->dma_tx_channel
->device
->dev
, pl022
->sgt_tx
.sgl
,
782 pl022
->sgt_tx
.nents
, DMA_TO_DEVICE
);
783 dma_unmap_sg(pl022
->dma_rx_channel
->device
->dev
, pl022
->sgt_rx
.sgl
,
784 pl022
->sgt_rx
.nents
, DMA_FROM_DEVICE
);
785 sg_free_table(&pl022
->sgt_rx
);
786 sg_free_table(&pl022
->sgt_tx
);
789 static void dma_callback(void *data
)
791 struct pl022
*pl022
= data
;
792 struct spi_message
*msg
= pl022
->cur_msg
;
794 BUG_ON(!pl022
->sgt_rx
.sgl
);
798 * Optionally dump out buffers to inspect contents, this is
799 * good if you want to convince yourself that the loopback
800 * read/write contents are the same, when adopting to a new
804 struct scatterlist
*sg
;
807 dma_sync_sg_for_cpu(&pl022
->adev
->dev
,
812 for_each_sg(pl022
->sgt_rx
.sgl
, sg
, pl022
->sgt_rx
.nents
, i
) {
813 dev_dbg(&pl022
->adev
->dev
, "SPI RX SG ENTRY: %d", i
);
814 print_hex_dump(KERN_ERR
, "SPI RX: ",
822 for_each_sg(pl022
->sgt_tx
.sgl
, sg
, pl022
->sgt_tx
.nents
, i
) {
823 dev_dbg(&pl022
->adev
->dev
, "SPI TX SG ENTRY: %d", i
);
824 print_hex_dump(KERN_ERR
, "SPI TX: ",
835 unmap_free_dma_scatter(pl022
);
837 /* Update total bytes transferred */
838 msg
->actual_length
+= pl022
->cur_transfer
->len
;
839 if (pl022
->cur_transfer
->cs_change
)
840 pl022_cs_control(pl022
, SSP_CHIP_DESELECT
);
842 /* Move to next transfer */
843 msg
->state
= next_transfer(pl022
);
844 tasklet_schedule(&pl022
->pump_transfers
);
847 static void setup_dma_scatter(struct pl022
*pl022
,
850 struct sg_table
*sgtab
)
852 struct scatterlist
*sg
;
853 int bytesleft
= length
;
859 for_each_sg(sgtab
->sgl
, sg
, sgtab
->nents
, i
) {
861 * If there are less bytes left than what fits
862 * in the current page (plus page alignment offset)
863 * we just feed in this, else we stuff in as much
866 if (bytesleft
< (PAGE_SIZE
- offset_in_page(bufp
)))
867 mapbytes
= bytesleft
;
869 mapbytes
= PAGE_SIZE
- offset_in_page(bufp
);
870 sg_set_page(sg
, virt_to_page(bufp
),
871 mapbytes
, offset_in_page(bufp
));
873 bytesleft
-= mapbytes
;
874 dev_dbg(&pl022
->adev
->dev
,
875 "set RX/TX target page @ %p, %d bytes, %d left\n",
876 bufp
, mapbytes
, bytesleft
);
879 /* Map the dummy buffer on every page */
880 for_each_sg(sgtab
->sgl
, sg
, sgtab
->nents
, i
) {
881 if (bytesleft
< PAGE_SIZE
)
882 mapbytes
= bytesleft
;
884 mapbytes
= PAGE_SIZE
;
885 sg_set_page(sg
, virt_to_page(pl022
->dummypage
),
887 bytesleft
-= mapbytes
;
888 dev_dbg(&pl022
->adev
->dev
,
889 "set RX/TX to dummy page %d bytes, %d left\n",
890 mapbytes
, bytesleft
);
898 * configure_dma - configures the channels for the next transfer
899 * @pl022: SSP driver's private data structure
901 static int configure_dma(struct pl022
*pl022
)
903 struct dma_slave_config rx_conf
= {
904 .src_addr
= SSP_DR(pl022
->phybase
),
905 .direction
= DMA_DEV_TO_MEM
,
908 struct dma_slave_config tx_conf
= {
909 .dst_addr
= SSP_DR(pl022
->phybase
),
910 .direction
= DMA_MEM_TO_DEV
,
915 int rx_sglen
, tx_sglen
;
916 struct dma_chan
*rxchan
= pl022
->dma_rx_channel
;
917 struct dma_chan
*txchan
= pl022
->dma_tx_channel
;
918 struct dma_async_tx_descriptor
*rxdesc
;
919 struct dma_async_tx_descriptor
*txdesc
;
921 /* Check that the channels are available */
922 if (!rxchan
|| !txchan
)
926 * If supplied, the DMA burstsize should equal the FIFO trigger level.
927 * Notice that the DMA engine uses one-to-one mapping. Since we can
928 * not trigger on 2 elements this needs explicit mapping rather than
931 switch (pl022
->rx_lev_trig
) {
932 case SSP_RX_1_OR_MORE_ELEM
:
933 rx_conf
.src_maxburst
= 1;
935 case SSP_RX_4_OR_MORE_ELEM
:
936 rx_conf
.src_maxburst
= 4;
938 case SSP_RX_8_OR_MORE_ELEM
:
939 rx_conf
.src_maxburst
= 8;
941 case SSP_RX_16_OR_MORE_ELEM
:
942 rx_conf
.src_maxburst
= 16;
944 case SSP_RX_32_OR_MORE_ELEM
:
945 rx_conf
.src_maxburst
= 32;
948 rx_conf
.src_maxburst
= pl022
->vendor
->fifodepth
>> 1;
952 switch (pl022
->tx_lev_trig
) {
953 case SSP_TX_1_OR_MORE_EMPTY_LOC
:
954 tx_conf
.dst_maxburst
= 1;
956 case SSP_TX_4_OR_MORE_EMPTY_LOC
:
957 tx_conf
.dst_maxburst
= 4;
959 case SSP_TX_8_OR_MORE_EMPTY_LOC
:
960 tx_conf
.dst_maxburst
= 8;
962 case SSP_TX_16_OR_MORE_EMPTY_LOC
:
963 tx_conf
.dst_maxburst
= 16;
965 case SSP_TX_32_OR_MORE_EMPTY_LOC
:
966 tx_conf
.dst_maxburst
= 32;
969 tx_conf
.dst_maxburst
= pl022
->vendor
->fifodepth
>> 1;
973 switch (pl022
->read
) {
975 /* Use the same as for writing */
976 rx_conf
.src_addr_width
= DMA_SLAVE_BUSWIDTH_UNDEFINED
;
979 rx_conf
.src_addr_width
= DMA_SLAVE_BUSWIDTH_1_BYTE
;
982 rx_conf
.src_addr_width
= DMA_SLAVE_BUSWIDTH_2_BYTES
;
985 rx_conf
.src_addr_width
= DMA_SLAVE_BUSWIDTH_4_BYTES
;
989 switch (pl022
->write
) {
991 /* Use the same as for reading */
992 tx_conf
.dst_addr_width
= DMA_SLAVE_BUSWIDTH_UNDEFINED
;
995 tx_conf
.dst_addr_width
= DMA_SLAVE_BUSWIDTH_1_BYTE
;
998 tx_conf
.dst_addr_width
= DMA_SLAVE_BUSWIDTH_2_BYTES
;
1001 tx_conf
.dst_addr_width
= DMA_SLAVE_BUSWIDTH_4_BYTES
;
1005 /* SPI pecularity: we need to read and write the same width */
1006 if (rx_conf
.src_addr_width
== DMA_SLAVE_BUSWIDTH_UNDEFINED
)
1007 rx_conf
.src_addr_width
= tx_conf
.dst_addr_width
;
1008 if (tx_conf
.dst_addr_width
== DMA_SLAVE_BUSWIDTH_UNDEFINED
)
1009 tx_conf
.dst_addr_width
= rx_conf
.src_addr_width
;
1010 BUG_ON(rx_conf
.src_addr_width
!= tx_conf
.dst_addr_width
);
1012 dmaengine_slave_config(rxchan
, &rx_conf
);
1013 dmaengine_slave_config(txchan
, &tx_conf
);
1015 /* Create sglists for the transfers */
1016 pages
= DIV_ROUND_UP(pl022
->cur_transfer
->len
, PAGE_SIZE
);
1017 dev_dbg(&pl022
->adev
->dev
, "using %d pages for transfer\n", pages
);
1019 ret
= sg_alloc_table(&pl022
->sgt_rx
, pages
, GFP_ATOMIC
);
1021 goto err_alloc_rx_sg
;
1023 ret
= sg_alloc_table(&pl022
->sgt_tx
, pages
, GFP_ATOMIC
);
1025 goto err_alloc_tx_sg
;
1027 /* Fill in the scatterlists for the RX+TX buffers */
1028 setup_dma_scatter(pl022
, pl022
->rx
,
1029 pl022
->cur_transfer
->len
, &pl022
->sgt_rx
);
1030 setup_dma_scatter(pl022
, pl022
->tx
,
1031 pl022
->cur_transfer
->len
, &pl022
->sgt_tx
);
1033 /* Map DMA buffers */
1034 rx_sglen
= dma_map_sg(rxchan
->device
->dev
, pl022
->sgt_rx
.sgl
,
1035 pl022
->sgt_rx
.nents
, DMA_FROM_DEVICE
);
1039 tx_sglen
= dma_map_sg(txchan
->device
->dev
, pl022
->sgt_tx
.sgl
,
1040 pl022
->sgt_tx
.nents
, DMA_TO_DEVICE
);
1044 /* Send both scatterlists */
1045 rxdesc
= dmaengine_prep_slave_sg(rxchan
,
1049 DMA_PREP_INTERRUPT
| DMA_CTRL_ACK
);
1053 txdesc
= dmaengine_prep_slave_sg(txchan
,
1057 DMA_PREP_INTERRUPT
| DMA_CTRL_ACK
);
1061 /* Put the callback on the RX transfer only, that should finish last */
1062 rxdesc
->callback
= dma_callback
;
1063 rxdesc
->callback_param
= pl022
;
1065 /* Submit and fire RX and TX with TX last so we're ready to read! */
1066 dmaengine_submit(rxdesc
);
1067 dmaengine_submit(txdesc
);
1068 dma_async_issue_pending(rxchan
);
1069 dma_async_issue_pending(txchan
);
1070 pl022
->dma_running
= true;
1075 dmaengine_terminate_all(txchan
);
1077 dmaengine_terminate_all(rxchan
);
1078 dma_unmap_sg(txchan
->device
->dev
, pl022
->sgt_tx
.sgl
,
1079 pl022
->sgt_tx
.nents
, DMA_TO_DEVICE
);
1081 dma_unmap_sg(rxchan
->device
->dev
, pl022
->sgt_rx
.sgl
,
1082 pl022
->sgt_tx
.nents
, DMA_FROM_DEVICE
);
1084 sg_free_table(&pl022
->sgt_tx
);
1086 sg_free_table(&pl022
->sgt_rx
);
1091 static int __devinit
pl022_dma_probe(struct pl022
*pl022
)
1093 dma_cap_mask_t mask
;
1095 /* Try to acquire a generic DMA engine slave channel */
1097 dma_cap_set(DMA_SLAVE
, mask
);
1099 * We need both RX and TX channels to do DMA, else do none
1102 pl022
->dma_rx_channel
= dma_request_channel(mask
,
1103 pl022
->master_info
->dma_filter
,
1104 pl022
->master_info
->dma_rx_param
);
1105 if (!pl022
->dma_rx_channel
) {
1106 dev_dbg(&pl022
->adev
->dev
, "no RX DMA channel!\n");
1110 pl022
->dma_tx_channel
= dma_request_channel(mask
,
1111 pl022
->master_info
->dma_filter
,
1112 pl022
->master_info
->dma_tx_param
);
1113 if (!pl022
->dma_tx_channel
) {
1114 dev_dbg(&pl022
->adev
->dev
, "no TX DMA channel!\n");
1118 pl022
->dummypage
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
1119 if (!pl022
->dummypage
) {
1120 dev_dbg(&pl022
->adev
->dev
, "no DMA dummypage!\n");
1121 goto err_no_dummypage
;
1124 dev_info(&pl022
->adev
->dev
, "setup for DMA on RX %s, TX %s\n",
1125 dma_chan_name(pl022
->dma_rx_channel
),
1126 dma_chan_name(pl022
->dma_tx_channel
));
1131 dma_release_channel(pl022
->dma_tx_channel
);
1133 dma_release_channel(pl022
->dma_rx_channel
);
1134 pl022
->dma_rx_channel
= NULL
;
1136 dev_err(&pl022
->adev
->dev
,
1137 "Failed to work in dma mode, work without dma!\n");
1141 static void terminate_dma(struct pl022
*pl022
)
1143 struct dma_chan
*rxchan
= pl022
->dma_rx_channel
;
1144 struct dma_chan
*txchan
= pl022
->dma_tx_channel
;
1146 dmaengine_terminate_all(rxchan
);
1147 dmaengine_terminate_all(txchan
);
1148 unmap_free_dma_scatter(pl022
);
1149 pl022
->dma_running
= false;
1152 static void pl022_dma_remove(struct pl022
*pl022
)
1154 if (pl022
->dma_running
)
1155 terminate_dma(pl022
);
1156 if (pl022
->dma_tx_channel
)
1157 dma_release_channel(pl022
->dma_tx_channel
);
1158 if (pl022
->dma_rx_channel
)
1159 dma_release_channel(pl022
->dma_rx_channel
);
1160 kfree(pl022
->dummypage
);
1164 static inline int configure_dma(struct pl022
*pl022
)
1169 static inline int pl022_dma_probe(struct pl022
*pl022
)
1174 static inline void pl022_dma_remove(struct pl022
*pl022
)
1180 * pl022_interrupt_handler - Interrupt handler for SSP controller
1182 * This function handles interrupts generated for an interrupt based transfer.
1183 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1184 * current message's state as STATE_ERROR and schedule the tasklet
1185 * pump_transfers which will do the postprocessing of the current message by
1186 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1187 * more data, and writes data in TX FIFO till it is not full. If we complete
1188 * the transfer we move to the next transfer and schedule the tasklet.
1190 static irqreturn_t
pl022_interrupt_handler(int irq
, void *dev_id
)
1192 struct pl022
*pl022
= dev_id
;
1193 struct spi_message
*msg
= pl022
->cur_msg
;
1197 if (unlikely(!msg
)) {
1198 dev_err(&pl022
->adev
->dev
,
1199 "bad message state in interrupt handler");
1204 /* Read the Interrupt Status Register */
1205 irq_status
= readw(SSP_MIS(pl022
->virtbase
));
1207 if (unlikely(!irq_status
))
1211 * This handles the FIFO interrupts, the timeout
1212 * interrupts are flatly ignored, they cannot be
1215 if (unlikely(irq_status
& SSP_MIS_MASK_RORMIS
)) {
1217 * Overrun interrupt - bail out since our Data has been
1220 dev_err(&pl022
->adev
->dev
, "FIFO overrun\n");
1221 if (readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_RFF
)
1222 dev_err(&pl022
->adev
->dev
,
1223 "RXFIFO is full\n");
1224 if (readw(SSP_SR(pl022
->virtbase
)) & SSP_SR_MASK_TNF
)
1225 dev_err(&pl022
->adev
->dev
,
1226 "TXFIFO is full\n");
1229 * Disable and clear interrupts, disable SSP,
1230 * mark message with bad status so it can be
1233 writew(DISABLE_ALL_INTERRUPTS
,
1234 SSP_IMSC(pl022
->virtbase
));
1235 writew(CLEAR_ALL_INTERRUPTS
, SSP_ICR(pl022
->virtbase
));
1236 writew((readw(SSP_CR1(pl022
->virtbase
)) &
1237 (~SSP_CR1_MASK_SSE
)), SSP_CR1(pl022
->virtbase
));
1238 msg
->state
= STATE_ERROR
;
1240 /* Schedule message queue handler */
1241 tasklet_schedule(&pl022
->pump_transfers
);
1247 if ((pl022
->tx
== pl022
->tx_end
) && (flag
== 0)) {
1249 /* Disable Transmit interrupt, enable receive interrupt */
1250 writew((readw(SSP_IMSC(pl022
->virtbase
)) &
1251 ~SSP_IMSC_MASK_TXIM
) | SSP_IMSC_MASK_RXIM
,
1252 SSP_IMSC(pl022
->virtbase
));
1256 * Since all transactions must write as much as shall be read,
1257 * we can conclude the entire transaction once RX is complete.
1258 * At this point, all TX will always be finished.
1260 if (pl022
->rx
>= pl022
->rx_end
) {
1261 writew(DISABLE_ALL_INTERRUPTS
,
1262 SSP_IMSC(pl022
->virtbase
));
1263 writew(CLEAR_ALL_INTERRUPTS
, SSP_ICR(pl022
->virtbase
));
1264 if (unlikely(pl022
->rx
> pl022
->rx_end
)) {
1265 dev_warn(&pl022
->adev
->dev
, "read %u surplus "
1266 "bytes (did you request an odd "
1267 "number of bytes on a 16bit bus?)\n",
1268 (u32
) (pl022
->rx
- pl022
->rx_end
));
1270 /* Update total bytes transferred */
1271 msg
->actual_length
+= pl022
->cur_transfer
->len
;
1272 if (pl022
->cur_transfer
->cs_change
)
1273 pl022_cs_control(pl022
, SSP_CHIP_DESELECT
);
1274 /* Move to next transfer */
1275 msg
->state
= next_transfer(pl022
);
1276 tasklet_schedule(&pl022
->pump_transfers
);
1284 * This sets up the pointers to memory for the next message to
1285 * send out on the SPI bus.
1287 static int set_up_next_transfer(struct pl022
*pl022
,
1288 struct spi_transfer
*transfer
)
1292 /* Sanity check the message for this bus width */
1293 residue
= pl022
->cur_transfer
->len
% pl022
->cur_chip
->n_bytes
;
1294 if (unlikely(residue
!= 0)) {
1295 dev_err(&pl022
->adev
->dev
,
1296 "message of %u bytes to transmit but the current "
1297 "chip bus has a data width of %u bytes!\n",
1298 pl022
->cur_transfer
->len
,
1299 pl022
->cur_chip
->n_bytes
);
1300 dev_err(&pl022
->adev
->dev
, "skipping this message\n");
1303 pl022
->tx
= (void *)transfer
->tx_buf
;
1304 pl022
->tx_end
= pl022
->tx
+ pl022
->cur_transfer
->len
;
1305 pl022
->rx
= (void *)transfer
->rx_buf
;
1306 pl022
->rx_end
= pl022
->rx
+ pl022
->cur_transfer
->len
;
1308 pl022
->tx
? pl022
->cur_chip
->write
: WRITING_NULL
;
1309 pl022
->read
= pl022
->rx
? pl022
->cur_chip
->read
: READING_NULL
;
1314 * pump_transfers - Tasklet function which schedules next transfer
1315 * when running in interrupt or DMA transfer mode.
1316 * @data: SSP driver private data structure
1319 static void pump_transfers(unsigned long data
)
1321 struct pl022
*pl022
= (struct pl022
*) data
;
1322 struct spi_message
*message
= NULL
;
1323 struct spi_transfer
*transfer
= NULL
;
1324 struct spi_transfer
*previous
= NULL
;
1326 /* Get current state information */
1327 message
= pl022
->cur_msg
;
1328 transfer
= pl022
->cur_transfer
;
1330 /* Handle for abort */
1331 if (message
->state
== STATE_ERROR
) {
1332 message
->status
= -EIO
;
1337 /* Handle end of message */
1338 if (message
->state
== STATE_DONE
) {
1339 message
->status
= 0;
1344 /* Delay if requested at end of transfer before CS change */
1345 if (message
->state
== STATE_RUNNING
) {
1346 previous
= list_entry(transfer
->transfer_list
.prev
,
1347 struct spi_transfer
,
1349 if (previous
->delay_usecs
)
1351 * FIXME: This runs in interrupt context.
1352 * Is this really smart?
1354 udelay(previous
->delay_usecs
);
1356 /* Reselect chip select only if cs_change was requested */
1357 if (previous
->cs_change
)
1358 pl022_cs_control(pl022
, SSP_CHIP_SELECT
);
1361 message
->state
= STATE_RUNNING
;
1364 if (set_up_next_transfer(pl022
, transfer
)) {
1365 message
->state
= STATE_ERROR
;
1366 message
->status
= -EIO
;
1370 /* Flush the FIFOs and let's go! */
1373 if (pl022
->cur_chip
->enable_dma
) {
1374 if (configure_dma(pl022
)) {
1375 dev_dbg(&pl022
->adev
->dev
,
1376 "configuration of DMA failed, fall back to interrupt mode\n");
1377 goto err_config_dma
;
1383 /* enable all interrupts except RX */
1384 writew(ENABLE_ALL_INTERRUPTS
& ~SSP_IMSC_MASK_RXIM
, SSP_IMSC(pl022
->virtbase
));
1387 static void do_interrupt_dma_transfer(struct pl022
*pl022
)
1390 * Default is to enable all interrupts except RX -
1391 * this will be enabled once TX is complete
1393 u32 irqflags
= ENABLE_ALL_INTERRUPTS
& ~SSP_IMSC_MASK_RXIM
;
1395 /* Enable target chip, if not already active */
1396 if (!pl022
->next_msg_cs_active
)
1397 pl022_cs_control(pl022
, SSP_CHIP_SELECT
);
1399 if (set_up_next_transfer(pl022
, pl022
->cur_transfer
)) {
1401 pl022
->cur_msg
->state
= STATE_ERROR
;
1402 pl022
->cur_msg
->status
= -EIO
;
1406 /* If we're using DMA, set up DMA here */
1407 if (pl022
->cur_chip
->enable_dma
) {
1408 /* Configure DMA transfer */
1409 if (configure_dma(pl022
)) {
1410 dev_dbg(&pl022
->adev
->dev
,
1411 "configuration of DMA failed, fall back to interrupt mode\n");
1412 goto err_config_dma
;
1414 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1415 irqflags
= DISABLE_ALL_INTERRUPTS
;
1418 /* Enable SSP, turn on interrupts */
1419 writew((readw(SSP_CR1(pl022
->virtbase
)) | SSP_CR1_MASK_SSE
),
1420 SSP_CR1(pl022
->virtbase
));
1421 writew(irqflags
, SSP_IMSC(pl022
->virtbase
));
1424 static void do_polling_transfer(struct pl022
*pl022
)
1426 struct spi_message
*message
= NULL
;
1427 struct spi_transfer
*transfer
= NULL
;
1428 struct spi_transfer
*previous
= NULL
;
1429 struct chip_data
*chip
;
1430 unsigned long time
, timeout
;
1432 chip
= pl022
->cur_chip
;
1433 message
= pl022
->cur_msg
;
1435 while (message
->state
!= STATE_DONE
) {
1436 /* Handle for abort */
1437 if (message
->state
== STATE_ERROR
)
1439 transfer
= pl022
->cur_transfer
;
1441 /* Delay if requested at end of transfer */
1442 if (message
->state
== STATE_RUNNING
) {
1444 list_entry(transfer
->transfer_list
.prev
,
1445 struct spi_transfer
, transfer_list
);
1446 if (previous
->delay_usecs
)
1447 udelay(previous
->delay_usecs
);
1448 if (previous
->cs_change
)
1449 pl022_cs_control(pl022
, SSP_CHIP_SELECT
);
1452 message
->state
= STATE_RUNNING
;
1453 if (!pl022
->next_msg_cs_active
)
1454 pl022_cs_control(pl022
, SSP_CHIP_SELECT
);
1457 /* Configuration Changing Per Transfer */
1458 if (set_up_next_transfer(pl022
, transfer
)) {
1460 message
->state
= STATE_ERROR
;
1463 /* Flush FIFOs and enable SSP */
1465 writew((readw(SSP_CR1(pl022
->virtbase
)) | SSP_CR1_MASK_SSE
),
1466 SSP_CR1(pl022
->virtbase
));
1468 dev_dbg(&pl022
->adev
->dev
, "polling transfer ongoing ...\n");
1470 timeout
= jiffies
+ msecs_to_jiffies(SPI_POLLING_TIMEOUT
);
1471 while (pl022
->tx
< pl022
->tx_end
|| pl022
->rx
< pl022
->rx_end
) {
1474 if (time_after(time
, timeout
)) {
1475 dev_warn(&pl022
->adev
->dev
,
1476 "%s: timeout!\n", __func__
);
1477 message
->state
= STATE_ERROR
;
1483 /* Update total byte transferred */
1484 message
->actual_length
+= pl022
->cur_transfer
->len
;
1485 if (pl022
->cur_transfer
->cs_change
)
1486 pl022_cs_control(pl022
, SSP_CHIP_DESELECT
);
1487 /* Move to next transfer */
1488 message
->state
= next_transfer(pl022
);
1491 /* Handle end of message */
1492 if (message
->state
== STATE_DONE
)
1493 message
->status
= 0;
1495 message
->status
= -EIO
;
1501 static int pl022_transfer_one_message(struct spi_master
*master
,
1502 struct spi_message
*msg
)
1504 struct pl022
*pl022
= spi_master_get_devdata(master
);
1506 /* Initial message state */
1507 pl022
->cur_msg
= msg
;
1508 msg
->state
= STATE_START
;
1510 pl022
->cur_transfer
= list_entry(msg
->transfers
.next
,
1511 struct spi_transfer
, transfer_list
);
1513 /* Setup the SPI using the per chip configuration */
1514 pl022
->cur_chip
= spi_get_ctldata(msg
->spi
);
1515 pl022
->cur_cs
= pl022
->chipselects
[msg
->spi
->chip_select
];
1517 restore_state(pl022
);
1520 if (pl022
->cur_chip
->xfer_type
== POLLING_TRANSFER
)
1521 do_polling_transfer(pl022
);
1523 do_interrupt_dma_transfer(pl022
);
1528 static int pl022_prepare_transfer_hardware(struct spi_master
*master
)
1530 struct pl022
*pl022
= spi_master_get_devdata(master
);
1533 * Just make sure we have all we need to run the transfer by syncing
1534 * with the runtime PM framework.
1536 pm_runtime_get_sync(&pl022
->adev
->dev
);
1540 static int pl022_unprepare_transfer_hardware(struct spi_master
*master
)
1542 struct pl022
*pl022
= spi_master_get_devdata(master
);
1544 /* nothing more to do - disable spi/ssp and power off */
1545 writew((readw(SSP_CR1(pl022
->virtbase
)) &
1546 (~SSP_CR1_MASK_SSE
)), SSP_CR1(pl022
->virtbase
));
1548 if (pl022
->master_info
->autosuspend_delay
> 0) {
1549 pm_runtime_mark_last_busy(&pl022
->adev
->dev
);
1550 pm_runtime_put_autosuspend(&pl022
->adev
->dev
);
1552 pm_runtime_put(&pl022
->adev
->dev
);
1558 static int verify_controller_parameters(struct pl022
*pl022
,
1559 struct pl022_config_chip
const *chip_info
)
1561 if ((chip_info
->iface
< SSP_INTERFACE_MOTOROLA_SPI
)
1562 || (chip_info
->iface
> SSP_INTERFACE_UNIDIRECTIONAL
)) {
1563 dev_err(&pl022
->adev
->dev
,
1564 "interface is configured incorrectly\n");
1567 if ((chip_info
->iface
== SSP_INTERFACE_UNIDIRECTIONAL
) &&
1568 (!pl022
->vendor
->unidir
)) {
1569 dev_err(&pl022
->adev
->dev
,
1570 "unidirectional mode not supported in this "
1571 "hardware version\n");
1574 if ((chip_info
->hierarchy
!= SSP_MASTER
)
1575 && (chip_info
->hierarchy
!= SSP_SLAVE
)) {
1576 dev_err(&pl022
->adev
->dev
,
1577 "hierarchy is configured incorrectly\n");
1580 if ((chip_info
->com_mode
!= INTERRUPT_TRANSFER
)
1581 && (chip_info
->com_mode
!= DMA_TRANSFER
)
1582 && (chip_info
->com_mode
!= POLLING_TRANSFER
)) {
1583 dev_err(&pl022
->adev
->dev
,
1584 "Communication mode is configured incorrectly\n");
1587 switch (chip_info
->rx_lev_trig
) {
1588 case SSP_RX_1_OR_MORE_ELEM
:
1589 case SSP_RX_4_OR_MORE_ELEM
:
1590 case SSP_RX_8_OR_MORE_ELEM
:
1591 /* These are always OK, all variants can handle this */
1593 case SSP_RX_16_OR_MORE_ELEM
:
1594 if (pl022
->vendor
->fifodepth
< 16) {
1595 dev_err(&pl022
->adev
->dev
,
1596 "RX FIFO Trigger Level is configured incorrectly\n");
1600 case SSP_RX_32_OR_MORE_ELEM
:
1601 if (pl022
->vendor
->fifodepth
< 32) {
1602 dev_err(&pl022
->adev
->dev
,
1603 "RX FIFO Trigger Level is configured incorrectly\n");
1608 dev_err(&pl022
->adev
->dev
,
1609 "RX FIFO Trigger Level is configured incorrectly\n");
1613 switch (chip_info
->tx_lev_trig
) {
1614 case SSP_TX_1_OR_MORE_EMPTY_LOC
:
1615 case SSP_TX_4_OR_MORE_EMPTY_LOC
:
1616 case SSP_TX_8_OR_MORE_EMPTY_LOC
:
1617 /* These are always OK, all variants can handle this */
1619 case SSP_TX_16_OR_MORE_EMPTY_LOC
:
1620 if (pl022
->vendor
->fifodepth
< 16) {
1621 dev_err(&pl022
->adev
->dev
,
1622 "TX FIFO Trigger Level is configured incorrectly\n");
1626 case SSP_TX_32_OR_MORE_EMPTY_LOC
:
1627 if (pl022
->vendor
->fifodepth
< 32) {
1628 dev_err(&pl022
->adev
->dev
,
1629 "TX FIFO Trigger Level is configured incorrectly\n");
1634 dev_err(&pl022
->adev
->dev
,
1635 "TX FIFO Trigger Level is configured incorrectly\n");
1639 if (chip_info
->iface
== SSP_INTERFACE_NATIONAL_MICROWIRE
) {
1640 if ((chip_info
->ctrl_len
< SSP_BITS_4
)
1641 || (chip_info
->ctrl_len
> SSP_BITS_32
)) {
1642 dev_err(&pl022
->adev
->dev
,
1643 "CTRL LEN is configured incorrectly\n");
1646 if ((chip_info
->wait_state
!= SSP_MWIRE_WAIT_ZERO
)
1647 && (chip_info
->wait_state
!= SSP_MWIRE_WAIT_ONE
)) {
1648 dev_err(&pl022
->adev
->dev
,
1649 "Wait State is configured incorrectly\n");
1652 /* Half duplex is only available in the ST Micro version */
1653 if (pl022
->vendor
->extended_cr
) {
1654 if ((chip_info
->duplex
!=
1655 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX
)
1656 && (chip_info
->duplex
!=
1657 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX
)) {
1658 dev_err(&pl022
->adev
->dev
,
1659 "Microwire duplex mode is configured incorrectly\n");
1663 if (chip_info
->duplex
!= SSP_MICROWIRE_CHANNEL_FULL_DUPLEX
)
1664 dev_err(&pl022
->adev
->dev
,
1665 "Microwire half duplex mode requested,"
1666 " but this is only available in the"
1667 " ST version of PL022\n");
1674 static inline u32
spi_rate(u32 rate
, u16 cpsdvsr
, u16 scr
)
1676 return rate
/ (cpsdvsr
* (1 + scr
));
1679 static int calculate_effective_freq(struct pl022
*pl022
, int freq
, struct
1680 ssp_clock_params
* clk_freq
)
1682 /* Lets calculate the frequency parameters */
1683 u16 cpsdvsr
= CPSDVR_MIN
, scr
= SCR_MIN
;
1684 u32 rate
, max_tclk
, min_tclk
, best_freq
= 0, best_cpsdvsr
= 0,
1685 best_scr
= 0, tmp
, found
= 0;
1687 rate
= clk_get_rate(pl022
->clk
);
1688 /* cpsdvscr = 2 & scr 0 */
1689 max_tclk
= spi_rate(rate
, CPSDVR_MIN
, SCR_MIN
);
1690 /* cpsdvsr = 254 & scr = 255 */
1691 min_tclk
= spi_rate(rate
, CPSDVR_MAX
, SCR_MAX
);
1693 if (freq
> max_tclk
)
1694 dev_warn(&pl022
->adev
->dev
,
1695 "Max speed that can be programmed is %d Hz, you requested %d\n",
1698 if (freq
< min_tclk
) {
1699 dev_err(&pl022
->adev
->dev
,
1700 "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1706 * best_freq will give closest possible available rate (<= requested
1707 * freq) for all values of scr & cpsdvsr.
1709 while ((cpsdvsr
<= CPSDVR_MAX
) && !found
) {
1710 while (scr
<= SCR_MAX
) {
1711 tmp
= spi_rate(rate
, cpsdvsr
, scr
);
1714 /* we need lower freq */
1720 * If found exact value, mark found and break.
1721 * If found more closer value, update and break.
1723 if (tmp
> best_freq
) {
1725 best_cpsdvsr
= cpsdvsr
;
1732 * increased scr will give lower rates, which are not
1741 WARN(!best_freq
, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1744 clk_freq
->cpsdvsr
= (u8
) (best_cpsdvsr
& 0xFF);
1745 clk_freq
->scr
= (u8
) (best_scr
& 0xFF);
1746 dev_dbg(&pl022
->adev
->dev
,
1747 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1749 dev_dbg(&pl022
->adev
->dev
, "SSP cpsdvsr = %d, scr = %d\n",
1750 clk_freq
->cpsdvsr
, clk_freq
->scr
);
1756 * A piece of default chip info unless the platform
1759 static const struct pl022_config_chip pl022_default_chip_info
= {
1760 .com_mode
= POLLING_TRANSFER
,
1761 .iface
= SSP_INTERFACE_MOTOROLA_SPI
,
1762 .hierarchy
= SSP_SLAVE
,
1763 .slave_tx_disable
= DO_NOT_DRIVE_TX
,
1764 .rx_lev_trig
= SSP_RX_1_OR_MORE_ELEM
,
1765 .tx_lev_trig
= SSP_TX_1_OR_MORE_EMPTY_LOC
,
1766 .ctrl_len
= SSP_BITS_8
,
1767 .wait_state
= SSP_MWIRE_WAIT_ZERO
,
1768 .duplex
= SSP_MICROWIRE_CHANNEL_FULL_DUPLEX
,
1769 .cs_control
= null_cs_control
,
1773 * pl022_setup - setup function registered to SPI master framework
1774 * @spi: spi device which is requesting setup
1776 * This function is registered to the SPI framework for this SPI master
1777 * controller. If it is the first time when setup is called by this device,
1778 * this function will initialize the runtime state for this chip and save
1779 * the same in the device structure. Else it will update the runtime info
1780 * with the updated chip info. Nothing is really being written to the
1781 * controller hardware here, that is not done until the actual transfer
1784 static int pl022_setup(struct spi_device
*spi
)
1786 struct pl022_config_chip
const *chip_info
;
1787 struct pl022_config_chip chip_info_dt
;
1788 struct chip_data
*chip
;
1789 struct ssp_clock_params clk_freq
= { .cpsdvsr
= 0, .scr
= 0};
1791 struct pl022
*pl022
= spi_master_get_devdata(spi
->master
);
1792 unsigned int bits
= spi
->bits_per_word
;
1794 struct device_node
*np
= spi
->dev
.of_node
;
1796 if (!spi
->max_speed_hz
)
1799 /* Get controller_state if one is supplied */
1800 chip
= spi_get_ctldata(spi
);
1803 chip
= kzalloc(sizeof(struct chip_data
), GFP_KERNEL
);
1806 "cannot allocate controller state\n");
1810 "allocated memory for controller's runtime state\n");
1813 /* Get controller data if one is supplied */
1814 chip_info
= spi
->controller_data
;
1816 if (chip_info
== NULL
) {
1818 chip_info_dt
= pl022_default_chip_info
;
1820 chip_info_dt
.hierarchy
= SSP_MASTER
;
1821 of_property_read_u32(np
, "pl022,interface",
1822 &chip_info_dt
.iface
);
1823 of_property_read_u32(np
, "pl022,com-mode",
1824 &chip_info_dt
.com_mode
);
1825 of_property_read_u32(np
, "pl022,rx-level-trig",
1826 &chip_info_dt
.rx_lev_trig
);
1827 of_property_read_u32(np
, "pl022,tx-level-trig",
1828 &chip_info_dt
.tx_lev_trig
);
1829 of_property_read_u32(np
, "pl022,ctrl-len",
1830 &chip_info_dt
.ctrl_len
);
1831 of_property_read_u32(np
, "pl022,wait-state",
1832 &chip_info_dt
.wait_state
);
1833 of_property_read_u32(np
, "pl022,duplex",
1834 &chip_info_dt
.duplex
);
1836 chip_info
= &chip_info_dt
;
1838 chip_info
= &pl022_default_chip_info
;
1839 /* spi_board_info.controller_data not is supplied */
1841 "using default controller_data settings\n");
1845 "using user supplied controller_data settings\n");
1848 * We can override with custom divisors, else we use the board
1851 if ((0 == chip_info
->clk_freq
.cpsdvsr
)
1852 && (0 == chip_info
->clk_freq
.scr
)) {
1853 status
= calculate_effective_freq(pl022
,
1857 goto err_config_params
;
1859 memcpy(&clk_freq
, &chip_info
->clk_freq
, sizeof(clk_freq
));
1860 if ((clk_freq
.cpsdvsr
% 2) != 0)
1862 clk_freq
.cpsdvsr
- 1;
1864 if ((clk_freq
.cpsdvsr
< CPSDVR_MIN
)
1865 || (clk_freq
.cpsdvsr
> CPSDVR_MAX
)) {
1868 "cpsdvsr is configured incorrectly\n");
1869 goto err_config_params
;
1872 status
= verify_controller_parameters(pl022
, chip_info
);
1874 dev_err(&spi
->dev
, "controller data is incorrect");
1875 goto err_config_params
;
1878 pl022
->rx_lev_trig
= chip_info
->rx_lev_trig
;
1879 pl022
->tx_lev_trig
= chip_info
->tx_lev_trig
;
1881 /* Now set controller state based on controller data */
1882 chip
->xfer_type
= chip_info
->com_mode
;
1883 if (!chip_info
->cs_control
) {
1884 chip
->cs_control
= null_cs_control
;
1885 if (!gpio_is_valid(pl022
->chipselects
[spi
->chip_select
]))
1887 "invalid chip select\n");
1889 chip
->cs_control
= chip_info
->cs_control
;
1891 /* Check bits per word with vendor specific range */
1892 if ((bits
<= 3) || (bits
> pl022
->vendor
->max_bpw
)) {
1894 dev_err(&spi
->dev
, "illegal data size for this controller!\n");
1895 dev_err(&spi
->dev
, "This controller can only handle 4 <= n <= %d bit words\n",
1896 pl022
->vendor
->max_bpw
);
1897 goto err_config_params
;
1898 } else if (bits
<= 8) {
1899 dev_dbg(&spi
->dev
, "4 <= n <=8 bits per word\n");
1901 chip
->read
= READING_U8
;
1902 chip
->write
= WRITING_U8
;
1903 } else if (bits
<= 16) {
1904 dev_dbg(&spi
->dev
, "9 <= n <= 16 bits per word\n");
1906 chip
->read
= READING_U16
;
1907 chip
->write
= WRITING_U16
;
1909 dev_dbg(&spi
->dev
, "17 <= n <= 32 bits per word\n");
1911 chip
->read
= READING_U32
;
1912 chip
->write
= WRITING_U32
;
1915 /* Now Initialize all register settings required for this chip */
1920 if ((chip_info
->com_mode
== DMA_TRANSFER
)
1921 && ((pl022
->master_info
)->enable_dma
)) {
1922 chip
->enable_dma
= true;
1923 dev_dbg(&spi
->dev
, "DMA mode set in controller state\n");
1924 SSP_WRITE_BITS(chip
->dmacr
, SSP_DMA_ENABLED
,
1925 SSP_DMACR_MASK_RXDMAE
, 0);
1926 SSP_WRITE_BITS(chip
->dmacr
, SSP_DMA_ENABLED
,
1927 SSP_DMACR_MASK_TXDMAE
, 1);
1929 chip
->enable_dma
= false;
1930 dev_dbg(&spi
->dev
, "DMA mode NOT set in controller state\n");
1931 SSP_WRITE_BITS(chip
->dmacr
, SSP_DMA_DISABLED
,
1932 SSP_DMACR_MASK_RXDMAE
, 0);
1933 SSP_WRITE_BITS(chip
->dmacr
, SSP_DMA_DISABLED
,
1934 SSP_DMACR_MASK_TXDMAE
, 1);
1937 chip
->cpsr
= clk_freq
.cpsdvsr
;
1939 /* Special setup for the ST micro extended control registers */
1940 if (pl022
->vendor
->extended_cr
) {
1943 if (pl022
->vendor
->pl023
) {
1944 /* These bits are only in the PL023 */
1945 SSP_WRITE_BITS(chip
->cr1
, chip_info
->clkdelay
,
1946 SSP_CR1_MASK_FBCLKDEL_ST
, 13);
1948 /* These bits are in the PL022 but not PL023 */
1949 SSP_WRITE_BITS(chip
->cr0
, chip_info
->duplex
,
1950 SSP_CR0_MASK_HALFDUP_ST
, 5);
1951 SSP_WRITE_BITS(chip
->cr0
, chip_info
->ctrl_len
,
1952 SSP_CR0_MASK_CSS_ST
, 16);
1953 SSP_WRITE_BITS(chip
->cr0
, chip_info
->iface
,
1954 SSP_CR0_MASK_FRF_ST
, 21);
1955 SSP_WRITE_BITS(chip
->cr1
, chip_info
->wait_state
,
1956 SSP_CR1_MASK_MWAIT_ST
, 6);
1958 SSP_WRITE_BITS(chip
->cr0
, bits
- 1,
1959 SSP_CR0_MASK_DSS_ST
, 0);
1961 if (spi
->mode
& SPI_LSB_FIRST
) {
1968 SSP_WRITE_BITS(chip
->cr1
, tmp
, SSP_CR1_MASK_RENDN_ST
, 4);
1969 SSP_WRITE_BITS(chip
->cr1
, etx
, SSP_CR1_MASK_TENDN_ST
, 5);
1970 SSP_WRITE_BITS(chip
->cr1
, chip_info
->rx_lev_trig
,
1971 SSP_CR1_MASK_RXIFLSEL_ST
, 7);
1972 SSP_WRITE_BITS(chip
->cr1
, chip_info
->tx_lev_trig
,
1973 SSP_CR1_MASK_TXIFLSEL_ST
, 10);
1975 SSP_WRITE_BITS(chip
->cr0
, bits
- 1,
1976 SSP_CR0_MASK_DSS
, 0);
1977 SSP_WRITE_BITS(chip
->cr0
, chip_info
->iface
,
1978 SSP_CR0_MASK_FRF
, 4);
1981 /* Stuff that is common for all versions */
1982 if (spi
->mode
& SPI_CPOL
)
1983 tmp
= SSP_CLK_POL_IDLE_HIGH
;
1985 tmp
= SSP_CLK_POL_IDLE_LOW
;
1986 SSP_WRITE_BITS(chip
->cr0
, tmp
, SSP_CR0_MASK_SPO
, 6);
1988 if (spi
->mode
& SPI_CPHA
)
1989 tmp
= SSP_CLK_SECOND_EDGE
;
1991 tmp
= SSP_CLK_FIRST_EDGE
;
1992 SSP_WRITE_BITS(chip
->cr0
, tmp
, SSP_CR0_MASK_SPH
, 7);
1994 SSP_WRITE_BITS(chip
->cr0
, clk_freq
.scr
, SSP_CR0_MASK_SCR
, 8);
1995 /* Loopback is available on all versions except PL023 */
1996 if (pl022
->vendor
->loopback
) {
1997 if (spi
->mode
& SPI_LOOP
)
1998 tmp
= LOOPBACK_ENABLED
;
2000 tmp
= LOOPBACK_DISABLED
;
2001 SSP_WRITE_BITS(chip
->cr1
, tmp
, SSP_CR1_MASK_LBM
, 0);
2003 SSP_WRITE_BITS(chip
->cr1
, SSP_DISABLED
, SSP_CR1_MASK_SSE
, 1);
2004 SSP_WRITE_BITS(chip
->cr1
, chip_info
->hierarchy
, SSP_CR1_MASK_MS
, 2);
2005 SSP_WRITE_BITS(chip
->cr1
, chip_info
->slave_tx_disable
, SSP_CR1_MASK_SOD
,
2008 /* Save controller_state */
2009 spi_set_ctldata(spi
, chip
);
2012 spi_set_ctldata(spi
, NULL
);
2018 * pl022_cleanup - cleanup function registered to SPI master framework
2019 * @spi: spi device which is requesting cleanup
2021 * This function is registered to the SPI framework for this SPI master
2022 * controller. It will free the runtime state of chip.
2024 static void pl022_cleanup(struct spi_device
*spi
)
2026 struct chip_data
*chip
= spi_get_ctldata(spi
);
2028 spi_set_ctldata(spi
, NULL
);
2032 static struct pl022_ssp_controller
*
2033 pl022_platform_data_dt_get(struct device
*dev
)
2035 struct device_node
*np
= dev
->of_node
;
2036 struct pl022_ssp_controller
*pd
;
2040 dev_err(dev
, "no dt node defined\n");
2044 pd
= devm_kzalloc(dev
, sizeof(struct pl022_ssp_controller
), GFP_KERNEL
);
2046 dev_err(dev
, "cannot allocate platform data memory\n");
2051 of_property_read_u32(np
, "num-cs", &tmp
);
2052 pd
->num_chipselect
= tmp
;
2053 of_property_read_u32(np
, "pl022,autosuspend-delay",
2054 &pd
->autosuspend_delay
);
2055 pd
->rt
= of_property_read_bool(np
, "pl022,rt");
2060 static int __devinit
2061 pl022_probe(struct amba_device
*adev
, const struct amba_id
*id
)
2063 struct device
*dev
= &adev
->dev
;
2064 struct pl022_ssp_controller
*platform_info
= adev
->dev
.platform_data
;
2065 struct spi_master
*master
;
2066 struct pl022
*pl022
= NULL
; /*Data for this driver */
2067 struct device_node
*np
= adev
->dev
.of_node
;
2068 int status
= 0, i
, num_cs
;
2070 dev_info(&adev
->dev
,
2071 "ARM PL022 driver, device ID: 0x%08x\n", adev
->periphid
);
2072 if (!platform_info
&& IS_ENABLED(CONFIG_OF
))
2073 platform_info
= pl022_platform_data_dt_get(dev
);
2075 if (!platform_info
) {
2076 dev_err(dev
, "probe: no platform data defined\n");
2080 if (platform_info
->num_chipselect
) {
2081 num_cs
= platform_info
->num_chipselect
;
2083 dev_err(dev
, "probe: no chip select defined\n");
2087 /* Allocate master with space for data */
2088 master
= spi_alloc_master(dev
, sizeof(struct pl022
));
2089 if (master
== NULL
) {
2090 dev_err(&adev
->dev
, "probe - cannot alloc SPI master\n");
2094 pl022
= spi_master_get_devdata(master
);
2095 pl022
->master
= master
;
2096 pl022
->master_info
= platform_info
;
2098 pl022
->vendor
= id
->data
;
2099 pl022
->chipselects
= devm_kzalloc(dev
, num_cs
* sizeof(int),
2102 pl022
->pinctrl
= devm_pinctrl_get(dev
);
2103 if (IS_ERR(pl022
->pinctrl
)) {
2104 status
= PTR_ERR(pl022
->pinctrl
);
2105 goto err_no_pinctrl
;
2108 pl022
->pins_default
= pinctrl_lookup_state(pl022
->pinctrl
,
2109 PINCTRL_STATE_DEFAULT
);
2110 /* enable pins to be muxed in and configured */
2111 if (!IS_ERR(pl022
->pins_default
)) {
2112 status
= pinctrl_select_state(pl022
->pinctrl
,
2113 pl022
->pins_default
);
2115 dev_err(dev
, "could not set default pins\n");
2117 dev_err(dev
, "could not get default pinstate\n");
2119 pl022
->pins_sleep
= pinctrl_lookup_state(pl022
->pinctrl
,
2120 PINCTRL_STATE_SLEEP
);
2121 if (IS_ERR(pl022
->pins_sleep
))
2122 dev_dbg(dev
, "could not get sleep pinstate\n");
2125 * Bus Number Which has been Assigned to this SSP controller
2128 master
->bus_num
= platform_info
->bus_id
;
2129 master
->num_chipselect
= num_cs
;
2130 master
->cleanup
= pl022_cleanup
;
2131 master
->setup
= pl022_setup
;
2132 master
->prepare_transfer_hardware
= pl022_prepare_transfer_hardware
;
2133 master
->transfer_one_message
= pl022_transfer_one_message
;
2134 master
->unprepare_transfer_hardware
= pl022_unprepare_transfer_hardware
;
2135 master
->rt
= platform_info
->rt
;
2136 master
->dev
.of_node
= dev
->of_node
;
2138 if (platform_info
->num_chipselect
&& platform_info
->chipselects
) {
2139 for (i
= 0; i
< num_cs
; i
++)
2140 pl022
->chipselects
[i
] = platform_info
->chipselects
[i
];
2141 } else if (IS_ENABLED(CONFIG_OF
)) {
2142 for (i
= 0; i
< num_cs
; i
++) {
2143 int cs_gpio
= of_get_named_gpio(np
, "cs-gpios", i
);
2145 if (cs_gpio
== -EPROBE_DEFER
) {
2146 status
= -EPROBE_DEFER
;
2150 pl022
->chipselects
[i
] = cs_gpio
;
2152 if (gpio_is_valid(cs_gpio
)) {
2153 if (devm_gpio_request(dev
, cs_gpio
, "ssp-pl022"))
2155 "could not request %d gpio\n",
2157 else if (gpio_direction_output(cs_gpio
, 1))
2159 "could set gpio %d as output\n",
2166 * Supports mode 0-3, loopback, and active low CS. Transfers are
2167 * always MS bit first on the original pl022.
2169 master
->mode_bits
= SPI_CPOL
| SPI_CPHA
| SPI_CS_HIGH
| SPI_LOOP
;
2170 if (pl022
->vendor
->extended_cr
)
2171 master
->mode_bits
|= SPI_LSB_FIRST
;
2173 dev_dbg(&adev
->dev
, "BUSNO: %d\n", master
->bus_num
);
2175 status
= amba_request_regions(adev
, NULL
);
2177 goto err_no_ioregion
;
2179 pl022
->phybase
= adev
->res
.start
;
2180 pl022
->virtbase
= devm_ioremap(dev
, adev
->res
.start
,
2181 resource_size(&adev
->res
));
2182 if (pl022
->virtbase
== NULL
) {
2184 goto err_no_ioremap
;
2186 printk(KERN_INFO
"pl022: mapped registers from 0x%08x to %p\n",
2187 adev
->res
.start
, pl022
->virtbase
);
2189 pl022
->clk
= devm_clk_get(&adev
->dev
, NULL
);
2190 if (IS_ERR(pl022
->clk
)) {
2191 status
= PTR_ERR(pl022
->clk
);
2192 dev_err(&adev
->dev
, "could not retrieve SSP/SPI bus clock\n");
2196 status
= clk_prepare(pl022
->clk
);
2198 dev_err(&adev
->dev
, "could not prepare SSP/SPI bus clock\n");
2202 status
= clk_enable(pl022
->clk
);
2204 dev_err(&adev
->dev
, "could not enable SSP/SPI bus clock\n");
2208 /* Initialize transfer pump */
2209 tasklet_init(&pl022
->pump_transfers
, pump_transfers
,
2210 (unsigned long)pl022
);
2213 writew((readw(SSP_CR1(pl022
->virtbase
)) & (~SSP_CR1_MASK_SSE
)),
2214 SSP_CR1(pl022
->virtbase
));
2215 load_ssp_default_config(pl022
);
2217 status
= devm_request_irq(dev
, adev
->irq
[0], pl022_interrupt_handler
,
2220 dev_err(&adev
->dev
, "probe - cannot get IRQ (%d)\n", status
);
2224 /* Get DMA channels */
2225 if (platform_info
->enable_dma
) {
2226 status
= pl022_dma_probe(pl022
);
2228 platform_info
->enable_dma
= 0;
2231 /* Register with the SPI framework */
2232 amba_set_drvdata(adev
, pl022
);
2233 status
= spi_register_master(master
);
2236 "probe - problem registering spi master\n");
2237 goto err_spi_register
;
2239 dev_dbg(dev
, "probe succeeded\n");
2241 /* let runtime pm put suspend */
2242 if (platform_info
->autosuspend_delay
> 0) {
2243 dev_info(&adev
->dev
,
2244 "will use autosuspend for runtime pm, delay %dms\n",
2245 platform_info
->autosuspend_delay
);
2246 pm_runtime_set_autosuspend_delay(dev
,
2247 platform_info
->autosuspend_delay
);
2248 pm_runtime_use_autosuspend(dev
);
2249 pm_runtime_put_autosuspend(dev
);
2251 pm_runtime_put(dev
);
2256 if (platform_info
->enable_dma
)
2257 pl022_dma_remove(pl022
);
2259 clk_disable(pl022
->clk
);
2261 clk_unprepare(pl022
->clk
);
2265 amba_release_regions(adev
);
2269 spi_master_put(master
);
2273 static int __devexit
2274 pl022_remove(struct amba_device
*adev
)
2276 struct pl022
*pl022
= amba_get_drvdata(adev
);
2282 * undo pm_runtime_put() in probe. I assume that we're not
2283 * accessing the primecell here.
2285 pm_runtime_get_noresume(&adev
->dev
);
2287 load_ssp_default_config(pl022
);
2288 if (pl022
->master_info
->enable_dma
)
2289 pl022_dma_remove(pl022
);
2291 clk_disable(pl022
->clk
);
2292 clk_unprepare(pl022
->clk
);
2293 amba_release_regions(adev
);
2294 tasklet_disable(&pl022
->pump_transfers
);
2295 spi_unregister_master(pl022
->master
);
2296 amba_set_drvdata(adev
, NULL
);
2300 #if defined(CONFIG_SUSPEND) || defined(CONFIG_PM_RUNTIME)
2302 * These two functions are used from both suspend/resume and
2303 * the runtime counterparts to handle external resources like
2304 * clocks, pins and regulators when going to sleep.
2306 static void pl022_suspend_resources(struct pl022
*pl022
)
2310 clk_disable(pl022
->clk
);
2312 /* Optionally let pins go into sleep states */
2313 if (!IS_ERR(pl022
->pins_sleep
)) {
2314 ret
= pinctrl_select_state(pl022
->pinctrl
,
2317 dev_err(&pl022
->adev
->dev
,
2318 "could not set pins to sleep state\n");
2322 static void pl022_resume_resources(struct pl022
*pl022
)
2326 /* Optionaly enable pins to be muxed in and configured */
2327 if (!IS_ERR(pl022
->pins_default
)) {
2328 ret
= pinctrl_select_state(pl022
->pinctrl
,
2329 pl022
->pins_default
);
2331 dev_err(&pl022
->adev
->dev
,
2332 "could not set default pins\n");
2335 clk_enable(pl022
->clk
);
2339 #ifdef CONFIG_SUSPEND
2340 static int pl022_suspend(struct device
*dev
)
2342 struct pl022
*pl022
= dev_get_drvdata(dev
);
2345 ret
= spi_master_suspend(pl022
->master
);
2347 dev_warn(dev
, "cannot suspend master\n");
2350 pl022_suspend_resources(pl022
);
2352 dev_dbg(dev
, "suspended\n");
2356 static int pl022_resume(struct device
*dev
)
2358 struct pl022
*pl022
= dev_get_drvdata(dev
);
2361 pl022_resume_resources(pl022
);
2363 /* Start the queue running */
2364 ret
= spi_master_resume(pl022
->master
);
2366 dev_err(dev
, "problem starting queue (%d)\n", ret
);
2368 dev_dbg(dev
, "resumed\n");
2372 #endif /* CONFIG_PM */
2374 #ifdef CONFIG_PM_RUNTIME
2375 static int pl022_runtime_suspend(struct device
*dev
)
2377 struct pl022
*pl022
= dev_get_drvdata(dev
);
2379 pl022_suspend_resources(pl022
);
2383 static int pl022_runtime_resume(struct device
*dev
)
2385 struct pl022
*pl022
= dev_get_drvdata(dev
);
2387 pl022_resume_resources(pl022
);
2392 static const struct dev_pm_ops pl022_dev_pm_ops
= {
2393 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend
, pl022_resume
)
2394 SET_RUNTIME_PM_OPS(pl022_runtime_suspend
, pl022_runtime_resume
, NULL
)
2397 static struct vendor_data vendor_arm
= {
2401 .extended_cr
= false,
2406 static struct vendor_data vendor_st
= {
2410 .extended_cr
= true,
2415 static struct vendor_data vendor_st_pl023
= {
2419 .extended_cr
= true,
2424 static struct amba_id pl022_ids
[] = {
2427 * ARM PL022 variant, this has a 16bit wide
2428 * and 8 locations deep TX/RX FIFO
2432 .data
= &vendor_arm
,
2436 * ST Micro derivative, this has 32bit wide
2437 * and 32 locations deep TX/RX FIFO
2445 * ST-Ericsson derivative "PL023" (this is not
2446 * an official ARM number), this is a PL022 SSP block
2447 * stripped to SPI mode only, it has 32bit wide
2448 * and 32 locations deep TX/RX FIFO but no extended
2453 .data
= &vendor_st_pl023
,
2458 MODULE_DEVICE_TABLE(amba
, pl022_ids
);
2460 static struct amba_driver pl022_driver
= {
2462 .name
= "ssp-pl022",
2463 .pm
= &pl022_dev_pm_ops
,
2465 .id_table
= pl022_ids
,
2466 .probe
= pl022_probe
,
2467 .remove
= __devexit_p(pl022_remove
),
2470 static int __init
pl022_init(void)
2472 return amba_driver_register(&pl022_driver
);
2474 subsys_initcall(pl022_init
);
2476 static void __exit
pl022_exit(void)
2478 amba_driver_unregister(&pl022_driver
);
2480 module_exit(pl022_exit
);
2482 MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2483 MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2484 MODULE_LICENSE("GPL");