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[pohmelfs.git] / drivers / spi / spi-pl022.c
blobf37ad2271ad53729ba857bb732b646ebe92333a7
1 /*
2 * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
4 * Copyright (C) 2008-2009 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/workqueue.h>
33 #include <linux/delay.h>
34 #include <linux/clk.h>
35 #include <linux/err.h>
36 #include <linux/amba/bus.h>
37 #include <linux/amba/pl022.h>
38 #include <linux/io.h>
39 #include <linux/slab.h>
40 #include <linux/dmaengine.h>
41 #include <linux/dma-mapping.h>
42 #include <linux/scatterlist.h>
43 #include <linux/pm_runtime.h>
46 * This macro is used to define some register default values.
47 * reg is masked with mask, the OR:ed with an (again masked)
48 * val shifted sb steps to the left.
50 #define SSP_WRITE_BITS(reg, val, mask, sb) \
51 ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
54 * This macro is also used to define some default values.
55 * It will just shift val by sb steps to the left and mask
56 * the result with mask.
58 #define GEN_MASK_BITS(val, mask, sb) \
59 (((val)<<(sb)) & (mask))
61 #define DRIVE_TX 0
62 #define DO_NOT_DRIVE_TX 1
64 #define DO_NOT_QUEUE_DMA 0
65 #define QUEUE_DMA 1
67 #define RX_TRANSFER 1
68 #define TX_TRANSFER 2
71 * Macros to access SSP Registers with their offsets
73 #define SSP_CR0(r) (r + 0x000)
74 #define SSP_CR1(r) (r + 0x004)
75 #define SSP_DR(r) (r + 0x008)
76 #define SSP_SR(r) (r + 0x00C)
77 #define SSP_CPSR(r) (r + 0x010)
78 #define SSP_IMSC(r) (r + 0x014)
79 #define SSP_RIS(r) (r + 0x018)
80 #define SSP_MIS(r) (r + 0x01C)
81 #define SSP_ICR(r) (r + 0x020)
82 #define SSP_DMACR(r) (r + 0x024)
83 #define SSP_ITCR(r) (r + 0x080)
84 #define SSP_ITIP(r) (r + 0x084)
85 #define SSP_ITOP(r) (r + 0x088)
86 #define SSP_TDR(r) (r + 0x08C)
88 #define SSP_PID0(r) (r + 0xFE0)
89 #define SSP_PID1(r) (r + 0xFE4)
90 #define SSP_PID2(r) (r + 0xFE8)
91 #define SSP_PID3(r) (r + 0xFEC)
93 #define SSP_CID0(r) (r + 0xFF0)
94 #define SSP_CID1(r) (r + 0xFF4)
95 #define SSP_CID2(r) (r + 0xFF8)
96 #define SSP_CID3(r) (r + 0xFFC)
99 * SSP Control Register 0 - SSP_CR0
101 #define SSP_CR0_MASK_DSS (0x0FUL << 0)
102 #define SSP_CR0_MASK_FRF (0x3UL << 4)
103 #define SSP_CR0_MASK_SPO (0x1UL << 6)
104 #define SSP_CR0_MASK_SPH (0x1UL << 7)
105 #define SSP_CR0_MASK_SCR (0xFFUL << 8)
108 * The ST version of this block moves som bits
109 * in SSP_CR0 and extends it to 32 bits
111 #define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
112 #define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
113 #define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
114 #define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
117 * SSP Control Register 0 - SSP_CR1
119 #define SSP_CR1_MASK_LBM (0x1UL << 0)
120 #define SSP_CR1_MASK_SSE (0x1UL << 1)
121 #define SSP_CR1_MASK_MS (0x1UL << 2)
122 #define SSP_CR1_MASK_SOD (0x1UL << 3)
125 * The ST version of this block adds some bits
126 * in SSP_CR1
128 #define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
129 #define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
130 #define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
131 #define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
132 #define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
133 /* This one is only in the PL023 variant */
134 #define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
137 * SSP Status Register - SSP_SR
139 #define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
140 #define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
141 #define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
142 #define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
143 #define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
146 * SSP Clock Prescale Register - SSP_CPSR
148 #define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
151 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
153 #define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
154 #define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
155 #define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
156 #define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
159 * SSP Raw Interrupt Status Register - SSP_RIS
161 /* Receive Overrun Raw Interrupt status */
162 #define SSP_RIS_MASK_RORRIS (0x1UL << 0)
163 /* Receive Timeout Raw Interrupt status */
164 #define SSP_RIS_MASK_RTRIS (0x1UL << 1)
165 /* Receive FIFO Raw Interrupt status */
166 #define SSP_RIS_MASK_RXRIS (0x1UL << 2)
167 /* Transmit FIFO Raw Interrupt status */
168 #define SSP_RIS_MASK_TXRIS (0x1UL << 3)
171 * SSP Masked Interrupt Status Register - SSP_MIS
173 /* Receive Overrun Masked Interrupt status */
174 #define SSP_MIS_MASK_RORMIS (0x1UL << 0)
175 /* Receive Timeout Masked Interrupt status */
176 #define SSP_MIS_MASK_RTMIS (0x1UL << 1)
177 /* Receive FIFO Masked Interrupt status */
178 #define SSP_MIS_MASK_RXMIS (0x1UL << 2)
179 /* Transmit FIFO Masked Interrupt status */
180 #define SSP_MIS_MASK_TXMIS (0x1UL << 3)
183 * SSP Interrupt Clear Register - SSP_ICR
185 /* Receive Overrun Raw Clear Interrupt bit */
186 #define SSP_ICR_MASK_RORIC (0x1UL << 0)
187 /* Receive Timeout Clear Interrupt bit */
188 #define SSP_ICR_MASK_RTIC (0x1UL << 1)
191 * SSP DMA Control Register - SSP_DMACR
193 /* Receive DMA Enable bit */
194 #define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
195 /* Transmit DMA Enable bit */
196 #define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
199 * SSP Integration Test control Register - SSP_ITCR
201 #define SSP_ITCR_MASK_ITEN (0x1UL << 0)
202 #define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
205 * SSP Integration Test Input Register - SSP_ITIP
207 #define ITIP_MASK_SSPRXD (0x1UL << 0)
208 #define ITIP_MASK_SSPFSSIN (0x1UL << 1)
209 #define ITIP_MASK_SSPCLKIN (0x1UL << 2)
210 #define ITIP_MASK_RXDMAC (0x1UL << 3)
211 #define ITIP_MASK_TXDMAC (0x1UL << 4)
212 #define ITIP_MASK_SSPTXDIN (0x1UL << 5)
215 * SSP Integration Test output Register - SSP_ITOP
217 #define ITOP_MASK_SSPTXD (0x1UL << 0)
218 #define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
219 #define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
220 #define ITOP_MASK_SSPOEn (0x1UL << 3)
221 #define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
222 #define ITOP_MASK_RORINTR (0x1UL << 5)
223 #define ITOP_MASK_RTINTR (0x1UL << 6)
224 #define ITOP_MASK_RXINTR (0x1UL << 7)
225 #define ITOP_MASK_TXINTR (0x1UL << 8)
226 #define ITOP_MASK_INTR (0x1UL << 9)
227 #define ITOP_MASK_RXDMABREQ (0x1UL << 10)
228 #define ITOP_MASK_RXDMASREQ (0x1UL << 11)
229 #define ITOP_MASK_TXDMABREQ (0x1UL << 12)
230 #define ITOP_MASK_TXDMASREQ (0x1UL << 13)
233 * SSP Test Data Register - SSP_TDR
235 #define TDR_MASK_TESTDATA (0xFFFFFFFF)
238 * Message State
239 * we use the spi_message.state (void *) pointer to
240 * hold a single state value, that's why all this
241 * (void *) casting is done here.
243 #define STATE_START ((void *) 0)
244 #define STATE_RUNNING ((void *) 1)
245 #define STATE_DONE ((void *) 2)
246 #define STATE_ERROR ((void *) -1)
249 * SSP State - Whether Enabled or Disabled
251 #define SSP_DISABLED (0)
252 #define SSP_ENABLED (1)
255 * SSP DMA State - Whether DMA Enabled or Disabled
257 #define SSP_DMA_DISABLED (0)
258 #define SSP_DMA_ENABLED (1)
261 * SSP Clock Defaults
263 #define SSP_DEFAULT_CLKRATE 0x2
264 #define SSP_DEFAULT_PRESCALE 0x40
267 * SSP Clock Parameter ranges
269 #define CPSDVR_MIN 0x02
270 #define CPSDVR_MAX 0xFE
271 #define SCR_MIN 0x00
272 #define SCR_MAX 0xFF
275 * SSP Interrupt related Macros
277 #define DEFAULT_SSP_REG_IMSC 0x0UL
278 #define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
279 #define ENABLE_ALL_INTERRUPTS (~DEFAULT_SSP_REG_IMSC)
281 #define CLEAR_ALL_INTERRUPTS 0x3
283 #define SPI_POLLING_TIMEOUT 1000
286 * The type of reading going on on this chip
288 enum ssp_reading {
289 READING_NULL,
290 READING_U8,
291 READING_U16,
292 READING_U32
296 * The type of writing going on on this chip
298 enum ssp_writing {
299 WRITING_NULL,
300 WRITING_U8,
301 WRITING_U16,
302 WRITING_U32
306 * struct vendor_data - vendor-specific config parameters
307 * for PL022 derivates
308 * @fifodepth: depth of FIFOs (both)
309 * @max_bpw: maximum number of bits per word
310 * @unidir: supports unidirection transfers
311 * @extended_cr: 32 bit wide control register 0 with extra
312 * features and extra features in CR1 as found in the ST variants
313 * @pl023: supports a subset of the ST extensions called "PL023"
315 struct vendor_data {
316 int fifodepth;
317 int max_bpw;
318 bool unidir;
319 bool extended_cr;
320 bool pl023;
321 bool loopback;
325 * struct pl022 - This is the private SSP driver data structure
326 * @adev: AMBA device model hookup
327 * @vendor: vendor data for the IP block
328 * @phybase: the physical memory where the SSP device resides
329 * @virtbase: the virtual memory where the SSP is mapped
330 * @clk: outgoing clock "SPICLK" for the SPI bus
331 * @master: SPI framework hookup
332 * @master_info: controller-specific data from machine setup
333 * @workqueue: a workqueue on which any spi_message request is queued
334 * @pump_messages: work struct for scheduling work to the workqueue
335 * @queue_lock: spinlock to syncronise access to message queue
336 * @queue: message queue
337 * @busy: workqueue is busy
338 * @running: workqueue is running
339 * @pump_transfers: Tasklet used in Interrupt Transfer mode
340 * @cur_msg: Pointer to current spi_message being processed
341 * @cur_transfer: Pointer to current spi_transfer
342 * @cur_chip: pointer to current clients chip(assigned from controller_state)
343 * @next_msg_cs_active: the next message in the queue has been examined
344 * and it was found that it uses the same chip select as the previous
345 * message, so we left it active after the previous transfer, and it's
346 * active already.
347 * @tx: current position in TX buffer to be read
348 * @tx_end: end position in TX buffer to be read
349 * @rx: current position in RX buffer to be written
350 * @rx_end: end position in RX buffer to be written
351 * @read: the type of read currently going on
352 * @write: the type of write currently going on
353 * @exp_fifo_level: expected FIFO level
354 * @dma_rx_channel: optional channel for RX DMA
355 * @dma_tx_channel: optional channel for TX DMA
356 * @sgt_rx: scattertable for the RX transfer
357 * @sgt_tx: scattertable for the TX transfer
358 * @dummypage: a dummy page used for driving data on the bus with DMA
360 struct pl022 {
361 struct amba_device *adev;
362 struct vendor_data *vendor;
363 resource_size_t phybase;
364 void __iomem *virtbase;
365 struct clk *clk;
366 struct spi_master *master;
367 struct pl022_ssp_controller *master_info;
368 /* Driver message queue */
369 struct workqueue_struct *workqueue;
370 struct work_struct pump_messages;
371 spinlock_t queue_lock;
372 struct list_head queue;
373 bool busy;
374 bool running;
375 /* Message transfer pump */
376 struct tasklet_struct pump_transfers;
377 struct spi_message *cur_msg;
378 struct spi_transfer *cur_transfer;
379 struct chip_data *cur_chip;
380 bool next_msg_cs_active;
381 void *tx;
382 void *tx_end;
383 void *rx;
384 void *rx_end;
385 enum ssp_reading read;
386 enum ssp_writing write;
387 u32 exp_fifo_level;
388 enum ssp_rx_level_trig rx_lev_trig;
389 enum ssp_tx_level_trig tx_lev_trig;
390 /* DMA settings */
391 #ifdef CONFIG_DMA_ENGINE
392 struct dma_chan *dma_rx_channel;
393 struct dma_chan *dma_tx_channel;
394 struct sg_table sgt_rx;
395 struct sg_table sgt_tx;
396 char *dummypage;
397 #endif
401 * struct chip_data - To maintain runtime state of SSP for each client chip
402 * @cr0: Value of control register CR0 of SSP - on later ST variants this
403 * register is 32 bits wide rather than just 16
404 * @cr1: Value of control register CR1 of SSP
405 * @dmacr: Value of DMA control Register of SSP
406 * @cpsr: Value of Clock prescale register
407 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
408 * @enable_dma: Whether to enable DMA or not
409 * @read: function ptr to be used to read when doing xfer for this chip
410 * @write: function ptr to be used to write when doing xfer for this chip
411 * @cs_control: chip select callback provided by chip
412 * @xfer_type: polling/interrupt/DMA
414 * Runtime state of the SSP controller, maintained per chip,
415 * This would be set according to the current message that would be served
417 struct chip_data {
418 u32 cr0;
419 u16 cr1;
420 u16 dmacr;
421 u16 cpsr;
422 u8 n_bytes;
423 bool enable_dma;
424 enum ssp_reading read;
425 enum ssp_writing write;
426 void (*cs_control) (u32 command);
427 int xfer_type;
431 * null_cs_control - Dummy chip select function
432 * @command: select/delect the chip
434 * If no chip select function is provided by client this is used as dummy
435 * chip select
437 static void null_cs_control(u32 command)
439 pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
443 * giveback - current spi_message is over, schedule next message and call
444 * callback of this message. Assumes that caller already
445 * set message->status; dma and pio irqs are blocked
446 * @pl022: SSP driver private data structure
448 static void giveback(struct pl022 *pl022)
450 struct spi_transfer *last_transfer;
451 unsigned long flags;
452 struct spi_message *msg;
453 pl022->next_msg_cs_active = false;
455 last_transfer = list_entry(pl022->cur_msg->transfers.prev,
456 struct spi_transfer,
457 transfer_list);
459 /* Delay if requested before any change in chip select */
460 if (last_transfer->delay_usecs)
462 * FIXME: This runs in interrupt context.
463 * Is this really smart?
465 udelay(last_transfer->delay_usecs);
467 if (!last_transfer->cs_change) {
468 struct spi_message *next_msg;
471 * cs_change was not set. We can keep the chip select
472 * enabled if there is message in the queue and it is
473 * for the same spi device.
475 * We cannot postpone this until pump_messages, because
476 * after calling msg->complete (below) the driver that
477 * sent the current message could be unloaded, which
478 * could invalidate the cs_control() callback...
481 /* get a pointer to the next message, if any */
482 spin_lock_irqsave(&pl022->queue_lock, flags);
483 if (list_empty(&pl022->queue))
484 next_msg = NULL;
485 else
486 next_msg = list_entry(pl022->queue.next,
487 struct spi_message, queue);
488 spin_unlock_irqrestore(&pl022->queue_lock, flags);
491 * see if the next and current messages point
492 * to the same spi device.
494 if (next_msg && next_msg->spi != pl022->cur_msg->spi)
495 next_msg = NULL;
496 if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
497 pl022->cur_chip->cs_control(SSP_CHIP_DESELECT);
498 else
499 pl022->next_msg_cs_active = true;
502 spin_lock_irqsave(&pl022->queue_lock, flags);
503 msg = pl022->cur_msg;
504 pl022->cur_msg = NULL;
505 pl022->cur_transfer = NULL;
506 pl022->cur_chip = NULL;
507 queue_work(pl022->workqueue, &pl022->pump_messages);
508 spin_unlock_irqrestore(&pl022->queue_lock, flags);
510 msg->state = NULL;
511 if (msg->complete)
512 msg->complete(msg->context);
516 * flush - flush the FIFO to reach a clean state
517 * @pl022: SSP driver private data structure
519 static int flush(struct pl022 *pl022)
521 unsigned long limit = loops_per_jiffy << 1;
523 dev_dbg(&pl022->adev->dev, "flush\n");
524 do {
525 while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
526 readw(SSP_DR(pl022->virtbase));
527 } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
529 pl022->exp_fifo_level = 0;
531 return limit;
535 * restore_state - Load configuration of current chip
536 * @pl022: SSP driver private data structure
538 static void restore_state(struct pl022 *pl022)
540 struct chip_data *chip = pl022->cur_chip;
542 if (pl022->vendor->extended_cr)
543 writel(chip->cr0, SSP_CR0(pl022->virtbase));
544 else
545 writew(chip->cr0, SSP_CR0(pl022->virtbase));
546 writew(chip->cr1, SSP_CR1(pl022->virtbase));
547 writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
548 writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
549 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
550 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
554 * Default SSP Register Values
556 #define DEFAULT_SSP_REG_CR0 ( \
557 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
558 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
559 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
560 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
561 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
564 /* ST versions have slightly different bit layout */
565 #define DEFAULT_SSP_REG_CR0_ST ( \
566 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
567 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
568 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
569 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
570 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
571 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
572 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
575 /* The PL023 version is slightly different again */
576 #define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
577 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
578 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
579 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
580 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
583 #define DEFAULT_SSP_REG_CR1 ( \
584 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
585 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
586 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
587 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
590 /* ST versions extend this register to use all 16 bits */
591 #define DEFAULT_SSP_REG_CR1_ST ( \
592 DEFAULT_SSP_REG_CR1 | \
593 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
594 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
595 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
596 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
597 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
601 * The PL023 variant has further differences: no loopback mode, no microwire
602 * support, and a new clock feedback delay setting.
604 #define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
605 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
606 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
607 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
608 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
609 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
610 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
611 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
612 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
615 #define DEFAULT_SSP_REG_CPSR ( \
616 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
619 #define DEFAULT_SSP_REG_DMACR (\
620 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
621 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
625 * load_ssp_default_config - Load default configuration for SSP
626 * @pl022: SSP driver private data structure
628 static void load_ssp_default_config(struct pl022 *pl022)
630 if (pl022->vendor->pl023) {
631 writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
632 writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
633 } else if (pl022->vendor->extended_cr) {
634 writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
635 writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
636 } else {
637 writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
638 writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
640 writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
641 writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
642 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
643 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
647 * This will write to TX and read from RX according to the parameters
648 * set in pl022.
650 static void readwriter(struct pl022 *pl022)
654 * The FIFO depth is different between primecell variants.
655 * I believe filling in too much in the FIFO might cause
656 * errons in 8bit wide transfers on ARM variants (just 8 words
657 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
659 * To prevent this issue, the TX FIFO is only filled to the
660 * unused RX FIFO fill length, regardless of what the TX
661 * FIFO status flag indicates.
663 dev_dbg(&pl022->adev->dev,
664 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
665 __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
667 /* Read as much as you can */
668 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
669 && (pl022->rx < pl022->rx_end)) {
670 switch (pl022->read) {
671 case READING_NULL:
672 readw(SSP_DR(pl022->virtbase));
673 break;
674 case READING_U8:
675 *(u8 *) (pl022->rx) =
676 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
677 break;
678 case READING_U16:
679 *(u16 *) (pl022->rx) =
680 (u16) readw(SSP_DR(pl022->virtbase));
681 break;
682 case READING_U32:
683 *(u32 *) (pl022->rx) =
684 readl(SSP_DR(pl022->virtbase));
685 break;
687 pl022->rx += (pl022->cur_chip->n_bytes);
688 pl022->exp_fifo_level--;
691 * Write as much as possible up to the RX FIFO size
693 while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
694 && (pl022->tx < pl022->tx_end)) {
695 switch (pl022->write) {
696 case WRITING_NULL:
697 writew(0x0, SSP_DR(pl022->virtbase));
698 break;
699 case WRITING_U8:
700 writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
701 break;
702 case WRITING_U16:
703 writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
704 break;
705 case WRITING_U32:
706 writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
707 break;
709 pl022->tx += (pl022->cur_chip->n_bytes);
710 pl022->exp_fifo_level++;
712 * This inner reader takes care of things appearing in the RX
713 * FIFO as we're transmitting. This will happen a lot since the
714 * clock starts running when you put things into the TX FIFO,
715 * and then things are continuously clocked into the RX FIFO.
717 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
718 && (pl022->rx < pl022->rx_end)) {
719 switch (pl022->read) {
720 case READING_NULL:
721 readw(SSP_DR(pl022->virtbase));
722 break;
723 case READING_U8:
724 *(u8 *) (pl022->rx) =
725 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
726 break;
727 case READING_U16:
728 *(u16 *) (pl022->rx) =
729 (u16) readw(SSP_DR(pl022->virtbase));
730 break;
731 case READING_U32:
732 *(u32 *) (pl022->rx) =
733 readl(SSP_DR(pl022->virtbase));
734 break;
736 pl022->rx += (pl022->cur_chip->n_bytes);
737 pl022->exp_fifo_level--;
741 * When we exit here the TX FIFO should be full and the RX FIFO
742 * should be empty
747 * next_transfer - Move to the Next transfer in the current spi message
748 * @pl022: SSP driver private data structure
750 * This function moves though the linked list of spi transfers in the
751 * current spi message and returns with the state of current spi
752 * message i.e whether its last transfer is done(STATE_DONE) or
753 * Next transfer is ready(STATE_RUNNING)
755 static void *next_transfer(struct pl022 *pl022)
757 struct spi_message *msg = pl022->cur_msg;
758 struct spi_transfer *trans = pl022->cur_transfer;
760 /* Move to next transfer */
761 if (trans->transfer_list.next != &msg->transfers) {
762 pl022->cur_transfer =
763 list_entry(trans->transfer_list.next,
764 struct spi_transfer, transfer_list);
765 return STATE_RUNNING;
767 return STATE_DONE;
771 * This DMA functionality is only compiled in if we have
772 * access to the generic DMA devices/DMA engine.
774 #ifdef CONFIG_DMA_ENGINE
775 static void unmap_free_dma_scatter(struct pl022 *pl022)
777 /* Unmap and free the SG tables */
778 dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
779 pl022->sgt_tx.nents, DMA_TO_DEVICE);
780 dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
781 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
782 sg_free_table(&pl022->sgt_rx);
783 sg_free_table(&pl022->sgt_tx);
786 static void dma_callback(void *data)
788 struct pl022 *pl022 = data;
789 struct spi_message *msg = pl022->cur_msg;
791 BUG_ON(!pl022->sgt_rx.sgl);
793 #ifdef VERBOSE_DEBUG
795 * Optionally dump out buffers to inspect contents, this is
796 * good if you want to convince yourself that the loopback
797 * read/write contents are the same, when adopting to a new
798 * DMA engine.
801 struct scatterlist *sg;
802 unsigned int i;
804 dma_sync_sg_for_cpu(&pl022->adev->dev,
805 pl022->sgt_rx.sgl,
806 pl022->sgt_rx.nents,
807 DMA_FROM_DEVICE);
809 for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
810 dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
811 print_hex_dump(KERN_ERR, "SPI RX: ",
812 DUMP_PREFIX_OFFSET,
815 sg_virt(sg),
816 sg_dma_len(sg),
819 for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
820 dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
821 print_hex_dump(KERN_ERR, "SPI TX: ",
822 DUMP_PREFIX_OFFSET,
825 sg_virt(sg),
826 sg_dma_len(sg),
830 #endif
832 unmap_free_dma_scatter(pl022);
834 /* Update total bytes transferred */
835 msg->actual_length += pl022->cur_transfer->len;
836 if (pl022->cur_transfer->cs_change)
837 pl022->cur_chip->
838 cs_control(SSP_CHIP_DESELECT);
840 /* Move to next transfer */
841 msg->state = next_transfer(pl022);
842 tasklet_schedule(&pl022->pump_transfers);
845 static void setup_dma_scatter(struct pl022 *pl022,
846 void *buffer,
847 unsigned int length,
848 struct sg_table *sgtab)
850 struct scatterlist *sg;
851 int bytesleft = length;
852 void *bufp = buffer;
853 int mapbytes;
854 int i;
856 if (buffer) {
857 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
859 * If there are less bytes left than what fits
860 * in the current page (plus page alignment offset)
861 * we just feed in this, else we stuff in as much
862 * as we can.
864 if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
865 mapbytes = bytesleft;
866 else
867 mapbytes = PAGE_SIZE - offset_in_page(bufp);
868 sg_set_page(sg, virt_to_page(bufp),
869 mapbytes, offset_in_page(bufp));
870 bufp += mapbytes;
871 bytesleft -= mapbytes;
872 dev_dbg(&pl022->adev->dev,
873 "set RX/TX target page @ %p, %d bytes, %d left\n",
874 bufp, mapbytes, bytesleft);
876 } else {
877 /* Map the dummy buffer on every page */
878 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
879 if (bytesleft < PAGE_SIZE)
880 mapbytes = bytesleft;
881 else
882 mapbytes = PAGE_SIZE;
883 sg_set_page(sg, virt_to_page(pl022->dummypage),
884 mapbytes, 0);
885 bytesleft -= mapbytes;
886 dev_dbg(&pl022->adev->dev,
887 "set RX/TX to dummy page %d bytes, %d left\n",
888 mapbytes, bytesleft);
892 BUG_ON(bytesleft);
896 * configure_dma - configures the channels for the next transfer
897 * @pl022: SSP driver's private data structure
899 static int configure_dma(struct pl022 *pl022)
901 struct dma_slave_config rx_conf = {
902 .src_addr = SSP_DR(pl022->phybase),
903 .direction = DMA_DEV_TO_MEM,
905 struct dma_slave_config tx_conf = {
906 .dst_addr = SSP_DR(pl022->phybase),
907 .direction = DMA_MEM_TO_DEV,
909 unsigned int pages;
910 int ret;
911 int rx_sglen, tx_sglen;
912 struct dma_chan *rxchan = pl022->dma_rx_channel;
913 struct dma_chan *txchan = pl022->dma_tx_channel;
914 struct dma_async_tx_descriptor *rxdesc;
915 struct dma_async_tx_descriptor *txdesc;
917 /* Check that the channels are available */
918 if (!rxchan || !txchan)
919 return -ENODEV;
922 * If supplied, the DMA burstsize should equal the FIFO trigger level.
923 * Notice that the DMA engine uses one-to-one mapping. Since we can
924 * not trigger on 2 elements this needs explicit mapping rather than
925 * calculation.
927 switch (pl022->rx_lev_trig) {
928 case SSP_RX_1_OR_MORE_ELEM:
929 rx_conf.src_maxburst = 1;
930 break;
931 case SSP_RX_4_OR_MORE_ELEM:
932 rx_conf.src_maxburst = 4;
933 break;
934 case SSP_RX_8_OR_MORE_ELEM:
935 rx_conf.src_maxburst = 8;
936 break;
937 case SSP_RX_16_OR_MORE_ELEM:
938 rx_conf.src_maxburst = 16;
939 break;
940 case SSP_RX_32_OR_MORE_ELEM:
941 rx_conf.src_maxburst = 32;
942 break;
943 default:
944 rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
945 break;
948 switch (pl022->tx_lev_trig) {
949 case SSP_TX_1_OR_MORE_EMPTY_LOC:
950 tx_conf.dst_maxburst = 1;
951 break;
952 case SSP_TX_4_OR_MORE_EMPTY_LOC:
953 tx_conf.dst_maxburst = 4;
954 break;
955 case SSP_TX_8_OR_MORE_EMPTY_LOC:
956 tx_conf.dst_maxburst = 8;
957 break;
958 case SSP_TX_16_OR_MORE_EMPTY_LOC:
959 tx_conf.dst_maxburst = 16;
960 break;
961 case SSP_TX_32_OR_MORE_EMPTY_LOC:
962 tx_conf.dst_maxburst = 32;
963 break;
964 default:
965 tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
966 break;
969 switch (pl022->read) {
970 case READING_NULL:
971 /* Use the same as for writing */
972 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
973 break;
974 case READING_U8:
975 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
976 break;
977 case READING_U16:
978 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
979 break;
980 case READING_U32:
981 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
982 break;
985 switch (pl022->write) {
986 case WRITING_NULL:
987 /* Use the same as for reading */
988 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
989 break;
990 case WRITING_U8:
991 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
992 break;
993 case WRITING_U16:
994 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
995 break;
996 case WRITING_U32:
997 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
998 break;
1001 /* SPI pecularity: we need to read and write the same width */
1002 if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1003 rx_conf.src_addr_width = tx_conf.dst_addr_width;
1004 if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1005 tx_conf.dst_addr_width = rx_conf.src_addr_width;
1006 BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
1008 dmaengine_slave_config(rxchan, &rx_conf);
1009 dmaengine_slave_config(txchan, &tx_conf);
1011 /* Create sglists for the transfers */
1012 pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
1013 dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
1015 ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
1016 if (ret)
1017 goto err_alloc_rx_sg;
1019 ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
1020 if (ret)
1021 goto err_alloc_tx_sg;
1023 /* Fill in the scatterlists for the RX+TX buffers */
1024 setup_dma_scatter(pl022, pl022->rx,
1025 pl022->cur_transfer->len, &pl022->sgt_rx);
1026 setup_dma_scatter(pl022, pl022->tx,
1027 pl022->cur_transfer->len, &pl022->sgt_tx);
1029 /* Map DMA buffers */
1030 rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1031 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1032 if (!rx_sglen)
1033 goto err_rx_sgmap;
1035 tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1036 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1037 if (!tx_sglen)
1038 goto err_tx_sgmap;
1040 /* Send both scatterlists */
1041 rxdesc = rxchan->device->device_prep_slave_sg(rxchan,
1042 pl022->sgt_rx.sgl,
1043 rx_sglen,
1044 DMA_DEV_TO_MEM,
1045 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1046 if (!rxdesc)
1047 goto err_rxdesc;
1049 txdesc = txchan->device->device_prep_slave_sg(txchan,
1050 pl022->sgt_tx.sgl,
1051 tx_sglen,
1052 DMA_MEM_TO_DEV,
1053 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1054 if (!txdesc)
1055 goto err_txdesc;
1057 /* Put the callback on the RX transfer only, that should finish last */
1058 rxdesc->callback = dma_callback;
1059 rxdesc->callback_param = pl022;
1061 /* Submit and fire RX and TX with TX last so we're ready to read! */
1062 dmaengine_submit(rxdesc);
1063 dmaengine_submit(txdesc);
1064 dma_async_issue_pending(rxchan);
1065 dma_async_issue_pending(txchan);
1067 return 0;
1069 err_txdesc:
1070 dmaengine_terminate_all(txchan);
1071 err_rxdesc:
1072 dmaengine_terminate_all(rxchan);
1073 dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1074 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1075 err_tx_sgmap:
1076 dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1077 pl022->sgt_tx.nents, DMA_FROM_DEVICE);
1078 err_rx_sgmap:
1079 sg_free_table(&pl022->sgt_tx);
1080 err_alloc_tx_sg:
1081 sg_free_table(&pl022->sgt_rx);
1082 err_alloc_rx_sg:
1083 return -ENOMEM;
1086 static int __devinit pl022_dma_probe(struct pl022 *pl022)
1088 dma_cap_mask_t mask;
1090 /* Try to acquire a generic DMA engine slave channel */
1091 dma_cap_zero(mask);
1092 dma_cap_set(DMA_SLAVE, mask);
1094 * We need both RX and TX channels to do DMA, else do none
1095 * of them.
1097 pl022->dma_rx_channel = dma_request_channel(mask,
1098 pl022->master_info->dma_filter,
1099 pl022->master_info->dma_rx_param);
1100 if (!pl022->dma_rx_channel) {
1101 dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1102 goto err_no_rxchan;
1105 pl022->dma_tx_channel = dma_request_channel(mask,
1106 pl022->master_info->dma_filter,
1107 pl022->master_info->dma_tx_param);
1108 if (!pl022->dma_tx_channel) {
1109 dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1110 goto err_no_txchan;
1113 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1114 if (!pl022->dummypage) {
1115 dev_dbg(&pl022->adev->dev, "no DMA dummypage!\n");
1116 goto err_no_dummypage;
1119 dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1120 dma_chan_name(pl022->dma_rx_channel),
1121 dma_chan_name(pl022->dma_tx_channel));
1123 return 0;
1125 err_no_dummypage:
1126 dma_release_channel(pl022->dma_tx_channel);
1127 err_no_txchan:
1128 dma_release_channel(pl022->dma_rx_channel);
1129 pl022->dma_rx_channel = NULL;
1130 err_no_rxchan:
1131 dev_err(&pl022->adev->dev,
1132 "Failed to work in dma mode, work without dma!\n");
1133 return -ENODEV;
1136 static void terminate_dma(struct pl022 *pl022)
1138 struct dma_chan *rxchan = pl022->dma_rx_channel;
1139 struct dma_chan *txchan = pl022->dma_tx_channel;
1141 dmaengine_terminate_all(rxchan);
1142 dmaengine_terminate_all(txchan);
1143 unmap_free_dma_scatter(pl022);
1146 static void pl022_dma_remove(struct pl022 *pl022)
1148 if (pl022->busy)
1149 terminate_dma(pl022);
1150 if (pl022->dma_tx_channel)
1151 dma_release_channel(pl022->dma_tx_channel);
1152 if (pl022->dma_rx_channel)
1153 dma_release_channel(pl022->dma_rx_channel);
1154 kfree(pl022->dummypage);
1157 #else
1158 static inline int configure_dma(struct pl022 *pl022)
1160 return -ENODEV;
1163 static inline int pl022_dma_probe(struct pl022 *pl022)
1165 return 0;
1168 static inline void pl022_dma_remove(struct pl022 *pl022)
1171 #endif
1174 * pl022_interrupt_handler - Interrupt handler for SSP controller
1176 * This function handles interrupts generated for an interrupt based transfer.
1177 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1178 * current message's state as STATE_ERROR and schedule the tasklet
1179 * pump_transfers which will do the postprocessing of the current message by
1180 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1181 * more data, and writes data in TX FIFO till it is not full. If we complete
1182 * the transfer we move to the next transfer and schedule the tasklet.
1184 static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1186 struct pl022 *pl022 = dev_id;
1187 struct spi_message *msg = pl022->cur_msg;
1188 u16 irq_status = 0;
1189 u16 flag = 0;
1191 if (unlikely(!msg)) {
1192 dev_err(&pl022->adev->dev,
1193 "bad message state in interrupt handler");
1194 /* Never fail */
1195 return IRQ_HANDLED;
1198 /* Read the Interrupt Status Register */
1199 irq_status = readw(SSP_MIS(pl022->virtbase));
1201 if (unlikely(!irq_status))
1202 return IRQ_NONE;
1205 * This handles the FIFO interrupts, the timeout
1206 * interrupts are flatly ignored, they cannot be
1207 * trusted.
1209 if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1211 * Overrun interrupt - bail out since our Data has been
1212 * corrupted
1214 dev_err(&pl022->adev->dev, "FIFO overrun\n");
1215 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1216 dev_err(&pl022->adev->dev,
1217 "RXFIFO is full\n");
1218 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF)
1219 dev_err(&pl022->adev->dev,
1220 "TXFIFO is full\n");
1223 * Disable and clear interrupts, disable SSP,
1224 * mark message with bad status so it can be
1225 * retried.
1227 writew(DISABLE_ALL_INTERRUPTS,
1228 SSP_IMSC(pl022->virtbase));
1229 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1230 writew((readw(SSP_CR1(pl022->virtbase)) &
1231 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1232 msg->state = STATE_ERROR;
1234 /* Schedule message queue handler */
1235 tasklet_schedule(&pl022->pump_transfers);
1236 return IRQ_HANDLED;
1239 readwriter(pl022);
1241 if ((pl022->tx == pl022->tx_end) && (flag == 0)) {
1242 flag = 1;
1243 /* Disable Transmit interrupt, enable receive interrupt */
1244 writew((readw(SSP_IMSC(pl022->virtbase)) &
1245 ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1246 SSP_IMSC(pl022->virtbase));
1250 * Since all transactions must write as much as shall be read,
1251 * we can conclude the entire transaction once RX is complete.
1252 * At this point, all TX will always be finished.
1254 if (pl022->rx >= pl022->rx_end) {
1255 writew(DISABLE_ALL_INTERRUPTS,
1256 SSP_IMSC(pl022->virtbase));
1257 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1258 if (unlikely(pl022->rx > pl022->rx_end)) {
1259 dev_warn(&pl022->adev->dev, "read %u surplus "
1260 "bytes (did you request an odd "
1261 "number of bytes on a 16bit bus?)\n",
1262 (u32) (pl022->rx - pl022->rx_end));
1264 /* Update total bytes transferred */
1265 msg->actual_length += pl022->cur_transfer->len;
1266 if (pl022->cur_transfer->cs_change)
1267 pl022->cur_chip->
1268 cs_control(SSP_CHIP_DESELECT);
1269 /* Move to next transfer */
1270 msg->state = next_transfer(pl022);
1271 tasklet_schedule(&pl022->pump_transfers);
1272 return IRQ_HANDLED;
1275 return IRQ_HANDLED;
1279 * This sets up the pointers to memory for the next message to
1280 * send out on the SPI bus.
1282 static int set_up_next_transfer(struct pl022 *pl022,
1283 struct spi_transfer *transfer)
1285 int residue;
1287 /* Sanity check the message for this bus width */
1288 residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1289 if (unlikely(residue != 0)) {
1290 dev_err(&pl022->adev->dev,
1291 "message of %u bytes to transmit but the current "
1292 "chip bus has a data width of %u bytes!\n",
1293 pl022->cur_transfer->len,
1294 pl022->cur_chip->n_bytes);
1295 dev_err(&pl022->adev->dev, "skipping this message\n");
1296 return -EIO;
1298 pl022->tx = (void *)transfer->tx_buf;
1299 pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1300 pl022->rx = (void *)transfer->rx_buf;
1301 pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1302 pl022->write =
1303 pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1304 pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1305 return 0;
1309 * pump_transfers - Tasklet function which schedules next transfer
1310 * when running in interrupt or DMA transfer mode.
1311 * @data: SSP driver private data structure
1314 static void pump_transfers(unsigned long data)
1316 struct pl022 *pl022 = (struct pl022 *) data;
1317 struct spi_message *message = NULL;
1318 struct spi_transfer *transfer = NULL;
1319 struct spi_transfer *previous = NULL;
1321 /* Get current state information */
1322 message = pl022->cur_msg;
1323 transfer = pl022->cur_transfer;
1325 /* Handle for abort */
1326 if (message->state == STATE_ERROR) {
1327 message->status = -EIO;
1328 giveback(pl022);
1329 return;
1332 /* Handle end of message */
1333 if (message->state == STATE_DONE) {
1334 message->status = 0;
1335 giveback(pl022);
1336 return;
1339 /* Delay if requested at end of transfer before CS change */
1340 if (message->state == STATE_RUNNING) {
1341 previous = list_entry(transfer->transfer_list.prev,
1342 struct spi_transfer,
1343 transfer_list);
1344 if (previous->delay_usecs)
1346 * FIXME: This runs in interrupt context.
1347 * Is this really smart?
1349 udelay(previous->delay_usecs);
1351 /* Reselect chip select only if cs_change was requested */
1352 if (previous->cs_change)
1353 pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1354 } else {
1355 /* STATE_START */
1356 message->state = STATE_RUNNING;
1359 if (set_up_next_transfer(pl022, transfer)) {
1360 message->state = STATE_ERROR;
1361 message->status = -EIO;
1362 giveback(pl022);
1363 return;
1365 /* Flush the FIFOs and let's go! */
1366 flush(pl022);
1368 if (pl022->cur_chip->enable_dma) {
1369 if (configure_dma(pl022)) {
1370 dev_dbg(&pl022->adev->dev,
1371 "configuration of DMA failed, fall back to interrupt mode\n");
1372 goto err_config_dma;
1374 return;
1377 err_config_dma:
1378 /* enable all interrupts except RX */
1379 writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
1382 static void do_interrupt_dma_transfer(struct pl022 *pl022)
1385 * Default is to enable all interrupts except RX -
1386 * this will be enabled once TX is complete
1388 u32 irqflags = ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM;
1390 /* Enable target chip, if not already active */
1391 if (!pl022->next_msg_cs_active)
1392 pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1394 if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
1395 /* Error path */
1396 pl022->cur_msg->state = STATE_ERROR;
1397 pl022->cur_msg->status = -EIO;
1398 giveback(pl022);
1399 return;
1401 /* If we're using DMA, set up DMA here */
1402 if (pl022->cur_chip->enable_dma) {
1403 /* Configure DMA transfer */
1404 if (configure_dma(pl022)) {
1405 dev_dbg(&pl022->adev->dev,
1406 "configuration of DMA failed, fall back to interrupt mode\n");
1407 goto err_config_dma;
1409 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1410 irqflags = DISABLE_ALL_INTERRUPTS;
1412 err_config_dma:
1413 /* Enable SSP, turn on interrupts */
1414 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1415 SSP_CR1(pl022->virtbase));
1416 writew(irqflags, SSP_IMSC(pl022->virtbase));
1419 static void do_polling_transfer(struct pl022 *pl022)
1421 struct spi_message *message = NULL;
1422 struct spi_transfer *transfer = NULL;
1423 struct spi_transfer *previous = NULL;
1424 struct chip_data *chip;
1425 unsigned long time, timeout;
1427 chip = pl022->cur_chip;
1428 message = pl022->cur_msg;
1430 while (message->state != STATE_DONE) {
1431 /* Handle for abort */
1432 if (message->state == STATE_ERROR)
1433 break;
1434 transfer = pl022->cur_transfer;
1436 /* Delay if requested at end of transfer */
1437 if (message->state == STATE_RUNNING) {
1438 previous =
1439 list_entry(transfer->transfer_list.prev,
1440 struct spi_transfer, transfer_list);
1441 if (previous->delay_usecs)
1442 udelay(previous->delay_usecs);
1443 if (previous->cs_change)
1444 pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1445 } else {
1446 /* STATE_START */
1447 message->state = STATE_RUNNING;
1448 if (!pl022->next_msg_cs_active)
1449 pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1452 /* Configuration Changing Per Transfer */
1453 if (set_up_next_transfer(pl022, transfer)) {
1454 /* Error path */
1455 message->state = STATE_ERROR;
1456 break;
1458 /* Flush FIFOs and enable SSP */
1459 flush(pl022);
1460 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1461 SSP_CR1(pl022->virtbase));
1463 dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1465 timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1466 while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1467 time = jiffies;
1468 readwriter(pl022);
1469 if (time_after(time, timeout)) {
1470 dev_warn(&pl022->adev->dev,
1471 "%s: timeout!\n", __func__);
1472 message->state = STATE_ERROR;
1473 goto out;
1475 cpu_relax();
1478 /* Update total byte transferred */
1479 message->actual_length += pl022->cur_transfer->len;
1480 if (pl022->cur_transfer->cs_change)
1481 pl022->cur_chip->cs_control(SSP_CHIP_DESELECT);
1482 /* Move to next transfer */
1483 message->state = next_transfer(pl022);
1485 out:
1486 /* Handle end of message */
1487 if (message->state == STATE_DONE)
1488 message->status = 0;
1489 else
1490 message->status = -EIO;
1492 giveback(pl022);
1493 return;
1497 * pump_messages - Workqueue function which processes spi message queue
1498 * @data: pointer to private data of SSP driver
1500 * This function checks if there is any spi message in the queue that
1501 * needs processing and delegate control to appropriate function
1502 * do_polling_transfer()/do_interrupt_dma_transfer()
1503 * based on the kind of the transfer
1506 static void pump_messages(struct work_struct *work)
1508 struct pl022 *pl022 =
1509 container_of(work, struct pl022, pump_messages);
1510 unsigned long flags;
1511 bool was_busy = false;
1513 /* Lock queue and check for queue work */
1514 spin_lock_irqsave(&pl022->queue_lock, flags);
1515 if (list_empty(&pl022->queue) || !pl022->running) {
1516 if (pl022->busy) {
1517 /* nothing more to do - disable spi/ssp and power off */
1518 writew((readw(SSP_CR1(pl022->virtbase)) &
1519 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1521 if (pl022->master_info->autosuspend_delay > 0) {
1522 pm_runtime_mark_last_busy(&pl022->adev->dev);
1523 pm_runtime_put_autosuspend(&pl022->adev->dev);
1524 } else {
1525 pm_runtime_put(&pl022->adev->dev);
1528 pl022->busy = false;
1529 spin_unlock_irqrestore(&pl022->queue_lock, flags);
1530 return;
1533 /* Make sure we are not already running a message */
1534 if (pl022->cur_msg) {
1535 spin_unlock_irqrestore(&pl022->queue_lock, flags);
1536 return;
1538 /* Extract head of queue */
1539 pl022->cur_msg =
1540 list_entry(pl022->queue.next, struct spi_message, queue);
1542 list_del_init(&pl022->cur_msg->queue);
1543 if (pl022->busy)
1544 was_busy = true;
1545 else
1546 pl022->busy = true;
1547 spin_unlock_irqrestore(&pl022->queue_lock, flags);
1549 /* Initial message state */
1550 pl022->cur_msg->state = STATE_START;
1551 pl022->cur_transfer = list_entry(pl022->cur_msg->transfers.next,
1552 struct spi_transfer, transfer_list);
1554 /* Setup the SPI using the per chip configuration */
1555 pl022->cur_chip = spi_get_ctldata(pl022->cur_msg->spi);
1556 if (!was_busy)
1558 * We enable the core voltage and clocks here, then the clocks
1559 * and core will be disabled when this workqueue is run again
1560 * and there is no more work to be done.
1562 pm_runtime_get_sync(&pl022->adev->dev);
1564 restore_state(pl022);
1565 flush(pl022);
1567 if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1568 do_polling_transfer(pl022);
1569 else
1570 do_interrupt_dma_transfer(pl022);
1573 static int __init init_queue(struct pl022 *pl022)
1575 INIT_LIST_HEAD(&pl022->queue);
1576 spin_lock_init(&pl022->queue_lock);
1578 pl022->running = false;
1579 pl022->busy = false;
1581 tasklet_init(&pl022->pump_transfers, pump_transfers,
1582 (unsigned long)pl022);
1584 INIT_WORK(&pl022->pump_messages, pump_messages);
1585 pl022->workqueue = create_singlethread_workqueue(
1586 dev_name(pl022->master->dev.parent));
1587 if (pl022->workqueue == NULL)
1588 return -EBUSY;
1590 return 0;
1593 static int start_queue(struct pl022 *pl022)
1595 unsigned long flags;
1597 spin_lock_irqsave(&pl022->queue_lock, flags);
1599 if (pl022->running || pl022->busy) {
1600 spin_unlock_irqrestore(&pl022->queue_lock, flags);
1601 return -EBUSY;
1604 pl022->running = true;
1605 pl022->cur_msg = NULL;
1606 pl022->cur_transfer = NULL;
1607 pl022->cur_chip = NULL;
1608 pl022->next_msg_cs_active = false;
1609 spin_unlock_irqrestore(&pl022->queue_lock, flags);
1611 queue_work(pl022->workqueue, &pl022->pump_messages);
1613 return 0;
1616 static int stop_queue(struct pl022 *pl022)
1618 unsigned long flags;
1619 unsigned limit = 500;
1620 int status = 0;
1622 spin_lock_irqsave(&pl022->queue_lock, flags);
1624 /* This is a bit lame, but is optimized for the common execution path.
1625 * A wait_queue on the pl022->busy could be used, but then the common
1626 * execution path (pump_messages) would be required to call wake_up or
1627 * friends on every SPI message. Do this instead */
1628 while ((!list_empty(&pl022->queue) || pl022->busy) && limit--) {
1629 spin_unlock_irqrestore(&pl022->queue_lock, flags);
1630 msleep(10);
1631 spin_lock_irqsave(&pl022->queue_lock, flags);
1634 if (!list_empty(&pl022->queue) || pl022->busy)
1635 status = -EBUSY;
1636 else
1637 pl022->running = false;
1639 spin_unlock_irqrestore(&pl022->queue_lock, flags);
1641 return status;
1644 static int destroy_queue(struct pl022 *pl022)
1646 int status;
1648 status = stop_queue(pl022);
1649 /* we are unloading the module or failing to load (only two calls
1650 * to this routine), and neither call can handle a return value.
1651 * However, destroy_workqueue calls flush_workqueue, and that will
1652 * block until all work is done. If the reason that stop_queue
1653 * timed out is that the work will never finish, then it does no
1654 * good to call destroy_workqueue, so return anyway. */
1655 if (status != 0)
1656 return status;
1658 destroy_workqueue(pl022->workqueue);
1660 return 0;
1663 static int verify_controller_parameters(struct pl022 *pl022,
1664 struct pl022_config_chip const *chip_info)
1666 if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1667 || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1668 dev_err(&pl022->adev->dev,
1669 "interface is configured incorrectly\n");
1670 return -EINVAL;
1672 if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1673 (!pl022->vendor->unidir)) {
1674 dev_err(&pl022->adev->dev,
1675 "unidirectional mode not supported in this "
1676 "hardware version\n");
1677 return -EINVAL;
1679 if ((chip_info->hierarchy != SSP_MASTER)
1680 && (chip_info->hierarchy != SSP_SLAVE)) {
1681 dev_err(&pl022->adev->dev,
1682 "hierarchy is configured incorrectly\n");
1683 return -EINVAL;
1685 if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1686 && (chip_info->com_mode != DMA_TRANSFER)
1687 && (chip_info->com_mode != POLLING_TRANSFER)) {
1688 dev_err(&pl022->adev->dev,
1689 "Communication mode is configured incorrectly\n");
1690 return -EINVAL;
1692 switch (chip_info->rx_lev_trig) {
1693 case SSP_RX_1_OR_MORE_ELEM:
1694 case SSP_RX_4_OR_MORE_ELEM:
1695 case SSP_RX_8_OR_MORE_ELEM:
1696 /* These are always OK, all variants can handle this */
1697 break;
1698 case SSP_RX_16_OR_MORE_ELEM:
1699 if (pl022->vendor->fifodepth < 16) {
1700 dev_err(&pl022->adev->dev,
1701 "RX FIFO Trigger Level is configured incorrectly\n");
1702 return -EINVAL;
1704 break;
1705 case SSP_RX_32_OR_MORE_ELEM:
1706 if (pl022->vendor->fifodepth < 32) {
1707 dev_err(&pl022->adev->dev,
1708 "RX FIFO Trigger Level is configured incorrectly\n");
1709 return -EINVAL;
1711 break;
1712 default:
1713 dev_err(&pl022->adev->dev,
1714 "RX FIFO Trigger Level is configured incorrectly\n");
1715 return -EINVAL;
1716 break;
1718 switch (chip_info->tx_lev_trig) {
1719 case SSP_TX_1_OR_MORE_EMPTY_LOC:
1720 case SSP_TX_4_OR_MORE_EMPTY_LOC:
1721 case SSP_TX_8_OR_MORE_EMPTY_LOC:
1722 /* These are always OK, all variants can handle this */
1723 break;
1724 case SSP_TX_16_OR_MORE_EMPTY_LOC:
1725 if (pl022->vendor->fifodepth < 16) {
1726 dev_err(&pl022->adev->dev,
1727 "TX FIFO Trigger Level is configured incorrectly\n");
1728 return -EINVAL;
1730 break;
1731 case SSP_TX_32_OR_MORE_EMPTY_LOC:
1732 if (pl022->vendor->fifodepth < 32) {
1733 dev_err(&pl022->adev->dev,
1734 "TX FIFO Trigger Level is configured incorrectly\n");
1735 return -EINVAL;
1737 break;
1738 default:
1739 dev_err(&pl022->adev->dev,
1740 "TX FIFO Trigger Level is configured incorrectly\n");
1741 return -EINVAL;
1742 break;
1744 if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1745 if ((chip_info->ctrl_len < SSP_BITS_4)
1746 || (chip_info->ctrl_len > SSP_BITS_32)) {
1747 dev_err(&pl022->adev->dev,
1748 "CTRL LEN is configured incorrectly\n");
1749 return -EINVAL;
1751 if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1752 && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1753 dev_err(&pl022->adev->dev,
1754 "Wait State is configured incorrectly\n");
1755 return -EINVAL;
1757 /* Half duplex is only available in the ST Micro version */
1758 if (pl022->vendor->extended_cr) {
1759 if ((chip_info->duplex !=
1760 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1761 && (chip_info->duplex !=
1762 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1763 dev_err(&pl022->adev->dev,
1764 "Microwire duplex mode is configured incorrectly\n");
1765 return -EINVAL;
1767 } else {
1768 if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1769 dev_err(&pl022->adev->dev,
1770 "Microwire half duplex mode requested,"
1771 " but this is only available in the"
1772 " ST version of PL022\n");
1773 return -EINVAL;
1776 return 0;
1780 * pl022_transfer - transfer function registered to SPI master framework
1781 * @spi: spi device which is requesting transfer
1782 * @msg: spi message which is to handled is queued to driver queue
1784 * This function is registered to the SPI framework for this SPI master
1785 * controller. It will queue the spi_message in the queue of driver if
1786 * the queue is not stopped and return.
1788 static int pl022_transfer(struct spi_device *spi, struct spi_message *msg)
1790 struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1791 unsigned long flags;
1793 spin_lock_irqsave(&pl022->queue_lock, flags);
1795 if (!pl022->running) {
1796 spin_unlock_irqrestore(&pl022->queue_lock, flags);
1797 return -ESHUTDOWN;
1799 msg->actual_length = 0;
1800 msg->status = -EINPROGRESS;
1801 msg->state = STATE_START;
1803 list_add_tail(&msg->queue, &pl022->queue);
1804 if (pl022->running && !pl022->busy)
1805 queue_work(pl022->workqueue, &pl022->pump_messages);
1807 spin_unlock_irqrestore(&pl022->queue_lock, flags);
1808 return 0;
1811 static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1813 return rate / (cpsdvsr * (1 + scr));
1816 static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1817 ssp_clock_params * clk_freq)
1819 /* Lets calculate the frequency parameters */
1820 u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1821 u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1822 best_scr = 0, tmp, found = 0;
1824 rate = clk_get_rate(pl022->clk);
1825 /* cpsdvscr = 2 & scr 0 */
1826 max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1827 /* cpsdvsr = 254 & scr = 255 */
1828 min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1830 if (!((freq <= max_tclk) && (freq >= min_tclk))) {
1831 dev_err(&pl022->adev->dev,
1832 "controller data is incorrect: out of range frequency");
1833 return -EINVAL;
1837 * best_freq will give closest possible available rate (<= requested
1838 * freq) for all values of scr & cpsdvsr.
1840 while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1841 while (scr <= SCR_MAX) {
1842 tmp = spi_rate(rate, cpsdvsr, scr);
1844 if (tmp > freq)
1845 scr++;
1847 * If found exact value, update and break.
1848 * If found more closer value, update and continue.
1850 else if ((tmp == freq) || (tmp > best_freq)) {
1851 best_freq = tmp;
1852 best_cpsdvsr = cpsdvsr;
1853 best_scr = scr;
1855 if (tmp == freq)
1856 break;
1858 scr++;
1860 cpsdvsr += 2;
1861 scr = SCR_MIN;
1864 clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1865 clk_freq->scr = (u8) (best_scr & 0xFF);
1866 dev_dbg(&pl022->adev->dev,
1867 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1868 freq, best_freq);
1869 dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1870 clk_freq->cpsdvsr, clk_freq->scr);
1872 return 0;
1876 * A piece of default chip info unless the platform
1877 * supplies it.
1879 static const struct pl022_config_chip pl022_default_chip_info = {
1880 .com_mode = POLLING_TRANSFER,
1881 .iface = SSP_INTERFACE_MOTOROLA_SPI,
1882 .hierarchy = SSP_SLAVE,
1883 .slave_tx_disable = DO_NOT_DRIVE_TX,
1884 .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1885 .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1886 .ctrl_len = SSP_BITS_8,
1887 .wait_state = SSP_MWIRE_WAIT_ZERO,
1888 .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1889 .cs_control = null_cs_control,
1893 * pl022_setup - setup function registered to SPI master framework
1894 * @spi: spi device which is requesting setup
1896 * This function is registered to the SPI framework for this SPI master
1897 * controller. If it is the first time when setup is called by this device,
1898 * this function will initialize the runtime state for this chip and save
1899 * the same in the device structure. Else it will update the runtime info
1900 * with the updated chip info. Nothing is really being written to the
1901 * controller hardware here, that is not done until the actual transfer
1902 * commence.
1904 static int pl022_setup(struct spi_device *spi)
1906 struct pl022_config_chip const *chip_info;
1907 struct chip_data *chip;
1908 struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1909 int status = 0;
1910 struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1911 unsigned int bits = spi->bits_per_word;
1912 u32 tmp;
1914 if (!spi->max_speed_hz)
1915 return -EINVAL;
1917 /* Get controller_state if one is supplied */
1918 chip = spi_get_ctldata(spi);
1920 if (chip == NULL) {
1921 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1922 if (!chip) {
1923 dev_err(&spi->dev,
1924 "cannot allocate controller state\n");
1925 return -ENOMEM;
1927 dev_dbg(&spi->dev,
1928 "allocated memory for controller's runtime state\n");
1931 /* Get controller data if one is supplied */
1932 chip_info = spi->controller_data;
1934 if (chip_info == NULL) {
1935 chip_info = &pl022_default_chip_info;
1936 /* spi_board_info.controller_data not is supplied */
1937 dev_dbg(&spi->dev,
1938 "using default controller_data settings\n");
1939 } else
1940 dev_dbg(&spi->dev,
1941 "using user supplied controller_data settings\n");
1944 * We can override with custom divisors, else we use the board
1945 * frequency setting
1947 if ((0 == chip_info->clk_freq.cpsdvsr)
1948 && (0 == chip_info->clk_freq.scr)) {
1949 status = calculate_effective_freq(pl022,
1950 spi->max_speed_hz,
1951 &clk_freq);
1952 if (status < 0)
1953 goto err_config_params;
1954 } else {
1955 memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1956 if ((clk_freq.cpsdvsr % 2) != 0)
1957 clk_freq.cpsdvsr =
1958 clk_freq.cpsdvsr - 1;
1960 if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1961 || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1962 status = -EINVAL;
1963 dev_err(&spi->dev,
1964 "cpsdvsr is configured incorrectly\n");
1965 goto err_config_params;
1968 status = verify_controller_parameters(pl022, chip_info);
1969 if (status) {
1970 dev_err(&spi->dev, "controller data is incorrect");
1971 goto err_config_params;
1974 pl022->rx_lev_trig = chip_info->rx_lev_trig;
1975 pl022->tx_lev_trig = chip_info->tx_lev_trig;
1977 /* Now set controller state based on controller data */
1978 chip->xfer_type = chip_info->com_mode;
1979 if (!chip_info->cs_control) {
1980 chip->cs_control = null_cs_control;
1981 dev_warn(&spi->dev,
1982 "chip select function is NULL for this chip\n");
1983 } else
1984 chip->cs_control = chip_info->cs_control;
1986 if (bits <= 3) {
1987 /* PL022 doesn't support less than 4-bits */
1988 status = -ENOTSUPP;
1989 goto err_config_params;
1990 } else if (bits <= 8) {
1991 dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1992 chip->n_bytes = 1;
1993 chip->read = READING_U8;
1994 chip->write = WRITING_U8;
1995 } else if (bits <= 16) {
1996 dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1997 chip->n_bytes = 2;
1998 chip->read = READING_U16;
1999 chip->write = WRITING_U16;
2000 } else {
2001 if (pl022->vendor->max_bpw >= 32) {
2002 dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
2003 chip->n_bytes = 4;
2004 chip->read = READING_U32;
2005 chip->write = WRITING_U32;
2006 } else {
2007 dev_err(&spi->dev,
2008 "illegal data size for this controller!\n");
2009 dev_err(&spi->dev,
2010 "a standard pl022 can only handle "
2011 "1 <= n <= 16 bit words\n");
2012 status = -ENOTSUPP;
2013 goto err_config_params;
2017 /* Now Initialize all register settings required for this chip */
2018 chip->cr0 = 0;
2019 chip->cr1 = 0;
2020 chip->dmacr = 0;
2021 chip->cpsr = 0;
2022 if ((chip_info->com_mode == DMA_TRANSFER)
2023 && ((pl022->master_info)->enable_dma)) {
2024 chip->enable_dma = true;
2025 dev_dbg(&spi->dev, "DMA mode set in controller state\n");
2026 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
2027 SSP_DMACR_MASK_RXDMAE, 0);
2028 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
2029 SSP_DMACR_MASK_TXDMAE, 1);
2030 } else {
2031 chip->enable_dma = false;
2032 dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
2033 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
2034 SSP_DMACR_MASK_RXDMAE, 0);
2035 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
2036 SSP_DMACR_MASK_TXDMAE, 1);
2039 chip->cpsr = clk_freq.cpsdvsr;
2041 /* Special setup for the ST micro extended control registers */
2042 if (pl022->vendor->extended_cr) {
2043 u32 etx;
2045 if (pl022->vendor->pl023) {
2046 /* These bits are only in the PL023 */
2047 SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
2048 SSP_CR1_MASK_FBCLKDEL_ST, 13);
2049 } else {
2050 /* These bits are in the PL022 but not PL023 */
2051 SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
2052 SSP_CR0_MASK_HALFDUP_ST, 5);
2053 SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
2054 SSP_CR0_MASK_CSS_ST, 16);
2055 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2056 SSP_CR0_MASK_FRF_ST, 21);
2057 SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
2058 SSP_CR1_MASK_MWAIT_ST, 6);
2060 SSP_WRITE_BITS(chip->cr0, bits - 1,
2061 SSP_CR0_MASK_DSS_ST, 0);
2063 if (spi->mode & SPI_LSB_FIRST) {
2064 tmp = SSP_RX_LSB;
2065 etx = SSP_TX_LSB;
2066 } else {
2067 tmp = SSP_RX_MSB;
2068 etx = SSP_TX_MSB;
2070 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
2071 SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
2072 SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
2073 SSP_CR1_MASK_RXIFLSEL_ST, 7);
2074 SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
2075 SSP_CR1_MASK_TXIFLSEL_ST, 10);
2076 } else {
2077 SSP_WRITE_BITS(chip->cr0, bits - 1,
2078 SSP_CR0_MASK_DSS, 0);
2079 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2080 SSP_CR0_MASK_FRF, 4);
2083 /* Stuff that is common for all versions */
2084 if (spi->mode & SPI_CPOL)
2085 tmp = SSP_CLK_POL_IDLE_HIGH;
2086 else
2087 tmp = SSP_CLK_POL_IDLE_LOW;
2088 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
2090 if (spi->mode & SPI_CPHA)
2091 tmp = SSP_CLK_SECOND_EDGE;
2092 else
2093 tmp = SSP_CLK_FIRST_EDGE;
2094 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
2096 SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
2097 /* Loopback is available on all versions except PL023 */
2098 if (pl022->vendor->loopback) {
2099 if (spi->mode & SPI_LOOP)
2100 tmp = LOOPBACK_ENABLED;
2101 else
2102 tmp = LOOPBACK_DISABLED;
2103 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
2105 SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
2106 SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
2107 SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
2110 /* Save controller_state */
2111 spi_set_ctldata(spi, chip);
2112 return status;
2113 err_config_params:
2114 spi_set_ctldata(spi, NULL);
2115 kfree(chip);
2116 return status;
2120 * pl022_cleanup - cleanup function registered to SPI master framework
2121 * @spi: spi device which is requesting cleanup
2123 * This function is registered to the SPI framework for this SPI master
2124 * controller. It will free the runtime state of chip.
2126 static void pl022_cleanup(struct spi_device *spi)
2128 struct chip_data *chip = spi_get_ctldata(spi);
2130 spi_set_ctldata(spi, NULL);
2131 kfree(chip);
2134 static int __devinit
2135 pl022_probe(struct amba_device *adev, const struct amba_id *id)
2137 struct device *dev = &adev->dev;
2138 struct pl022_ssp_controller *platform_info = adev->dev.platform_data;
2139 struct spi_master *master;
2140 struct pl022 *pl022 = NULL; /*Data for this driver */
2141 int status = 0;
2143 dev_info(&adev->dev,
2144 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
2145 if (platform_info == NULL) {
2146 dev_err(&adev->dev, "probe - no platform data supplied\n");
2147 status = -ENODEV;
2148 goto err_no_pdata;
2151 /* Allocate master with space for data */
2152 master = spi_alloc_master(dev, sizeof(struct pl022));
2153 if (master == NULL) {
2154 dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
2155 status = -ENOMEM;
2156 goto err_no_master;
2159 pl022 = spi_master_get_devdata(master);
2160 pl022->master = master;
2161 pl022->master_info = platform_info;
2162 pl022->adev = adev;
2163 pl022->vendor = id->data;
2166 * Bus Number Which has been Assigned to this SSP controller
2167 * on this board
2169 master->bus_num = platform_info->bus_id;
2170 master->num_chipselect = platform_info->num_chipselect;
2171 master->cleanup = pl022_cleanup;
2172 master->setup = pl022_setup;
2173 master->transfer = pl022_transfer;
2176 * Supports mode 0-3, loopback, and active low CS. Transfers are
2177 * always MS bit first on the original pl022.
2179 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
2180 if (pl022->vendor->extended_cr)
2181 master->mode_bits |= SPI_LSB_FIRST;
2183 dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
2185 status = amba_request_regions(adev, NULL);
2186 if (status)
2187 goto err_no_ioregion;
2189 pl022->phybase = adev->res.start;
2190 pl022->virtbase = ioremap(adev->res.start, resource_size(&adev->res));
2191 if (pl022->virtbase == NULL) {
2192 status = -ENOMEM;
2193 goto err_no_ioremap;
2195 printk(KERN_INFO "pl022: mapped registers from 0x%08x to %p\n",
2196 adev->res.start, pl022->virtbase);
2198 pl022->clk = clk_get(&adev->dev, NULL);
2199 if (IS_ERR(pl022->clk)) {
2200 status = PTR_ERR(pl022->clk);
2201 dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
2202 goto err_no_clk;
2205 status = clk_prepare(pl022->clk);
2206 if (status) {
2207 dev_err(&adev->dev, "could not prepare SSP/SPI bus clock\n");
2208 goto err_clk_prep;
2211 status = clk_enable(pl022->clk);
2212 if (status) {
2213 dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
2214 goto err_no_clk_en;
2217 /* Disable SSP */
2218 writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
2219 SSP_CR1(pl022->virtbase));
2220 load_ssp_default_config(pl022);
2222 status = request_irq(adev->irq[0], pl022_interrupt_handler, 0, "pl022",
2223 pl022);
2224 if (status < 0) {
2225 dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
2226 goto err_no_irq;
2229 /* Get DMA channels */
2230 if (platform_info->enable_dma) {
2231 status = pl022_dma_probe(pl022);
2232 if (status != 0)
2233 platform_info->enable_dma = 0;
2236 /* Initialize and start queue */
2237 status = init_queue(pl022);
2238 if (status != 0) {
2239 dev_err(&adev->dev, "probe - problem initializing queue\n");
2240 goto err_init_queue;
2242 status = start_queue(pl022);
2243 if (status != 0) {
2244 dev_err(&adev->dev, "probe - problem starting queue\n");
2245 goto err_start_queue;
2247 /* Register with the SPI framework */
2248 amba_set_drvdata(adev, pl022);
2249 status = spi_register_master(master);
2250 if (status != 0) {
2251 dev_err(&adev->dev,
2252 "probe - problem registering spi master\n");
2253 goto err_spi_register;
2255 dev_dbg(dev, "probe succeeded\n");
2257 /* let runtime pm put suspend */
2258 if (platform_info->autosuspend_delay > 0) {
2259 dev_info(&adev->dev,
2260 "will use autosuspend for runtime pm, delay %dms\n",
2261 platform_info->autosuspend_delay);
2262 pm_runtime_set_autosuspend_delay(dev,
2263 platform_info->autosuspend_delay);
2264 pm_runtime_use_autosuspend(dev);
2265 pm_runtime_put_autosuspend(dev);
2266 } else {
2267 pm_runtime_put(dev);
2269 return 0;
2271 err_spi_register:
2272 err_start_queue:
2273 err_init_queue:
2274 destroy_queue(pl022);
2275 if (platform_info->enable_dma)
2276 pl022_dma_remove(pl022);
2278 free_irq(adev->irq[0], pl022);
2279 err_no_irq:
2280 clk_disable(pl022->clk);
2281 err_no_clk_en:
2282 clk_unprepare(pl022->clk);
2283 err_clk_prep:
2284 clk_put(pl022->clk);
2285 err_no_clk:
2286 iounmap(pl022->virtbase);
2287 err_no_ioremap:
2288 amba_release_regions(adev);
2289 err_no_ioregion:
2290 spi_master_put(master);
2291 err_no_master:
2292 err_no_pdata:
2293 return status;
2296 static int __devexit
2297 pl022_remove(struct amba_device *adev)
2299 struct pl022 *pl022 = amba_get_drvdata(adev);
2301 if (!pl022)
2302 return 0;
2305 * undo pm_runtime_put() in probe. I assume that we're not
2306 * accessing the primecell here.
2308 pm_runtime_get_noresume(&adev->dev);
2310 /* Remove the queue */
2311 if (destroy_queue(pl022) != 0)
2312 dev_err(&adev->dev, "queue remove failed\n");
2313 load_ssp_default_config(pl022);
2314 if (pl022->master_info->enable_dma)
2315 pl022_dma_remove(pl022);
2317 free_irq(adev->irq[0], pl022);
2318 clk_disable(pl022->clk);
2319 clk_unprepare(pl022->clk);
2320 clk_put(pl022->clk);
2321 iounmap(pl022->virtbase);
2322 amba_release_regions(adev);
2323 tasklet_disable(&pl022->pump_transfers);
2324 spi_unregister_master(pl022->master);
2325 spi_master_put(pl022->master);
2326 amba_set_drvdata(adev, NULL);
2327 return 0;
2330 #ifdef CONFIG_SUSPEND
2331 static int pl022_suspend(struct device *dev)
2333 struct pl022 *pl022 = dev_get_drvdata(dev);
2334 int status = 0;
2336 status = stop_queue(pl022);
2337 if (status) {
2338 dev_warn(dev, "suspend cannot stop queue\n");
2339 return status;
2342 dev_dbg(dev, "suspended\n");
2343 return 0;
2346 static int pl022_resume(struct device *dev)
2348 struct pl022 *pl022 = dev_get_drvdata(dev);
2349 int status = 0;
2351 /* Start the queue running */
2352 status = start_queue(pl022);
2353 if (status)
2354 dev_err(dev, "problem starting queue (%d)\n", status);
2355 else
2356 dev_dbg(dev, "resumed\n");
2358 return status;
2360 #endif /* CONFIG_PM */
2362 #ifdef CONFIG_PM_RUNTIME
2363 static int pl022_runtime_suspend(struct device *dev)
2365 struct pl022 *pl022 = dev_get_drvdata(dev);
2367 clk_disable(pl022->clk);
2368 amba_vcore_disable(pl022->adev);
2370 return 0;
2373 static int pl022_runtime_resume(struct device *dev)
2375 struct pl022 *pl022 = dev_get_drvdata(dev);
2377 amba_vcore_enable(pl022->adev);
2378 clk_enable(pl022->clk);
2380 return 0;
2382 #endif
2384 static const struct dev_pm_ops pl022_dev_pm_ops = {
2385 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2386 SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2389 static struct vendor_data vendor_arm = {
2390 .fifodepth = 8,
2391 .max_bpw = 16,
2392 .unidir = false,
2393 .extended_cr = false,
2394 .pl023 = false,
2395 .loopback = true,
2398 static struct vendor_data vendor_st = {
2399 .fifodepth = 32,
2400 .max_bpw = 32,
2401 .unidir = false,
2402 .extended_cr = true,
2403 .pl023 = false,
2404 .loopback = true,
2407 static struct vendor_data vendor_st_pl023 = {
2408 .fifodepth = 32,
2409 .max_bpw = 32,
2410 .unidir = false,
2411 .extended_cr = true,
2412 .pl023 = true,
2413 .loopback = false,
2416 static struct vendor_data vendor_db5500_pl023 = {
2417 .fifodepth = 32,
2418 .max_bpw = 32,
2419 .unidir = false,
2420 .extended_cr = true,
2421 .pl023 = true,
2422 .loopback = true,
2425 static struct amba_id pl022_ids[] = {
2428 * ARM PL022 variant, this has a 16bit wide
2429 * and 8 locations deep TX/RX FIFO
2431 .id = 0x00041022,
2432 .mask = 0x000fffff,
2433 .data = &vendor_arm,
2437 * ST Micro derivative, this has 32bit wide
2438 * and 32 locations deep TX/RX FIFO
2440 .id = 0x01080022,
2441 .mask = 0xffffffff,
2442 .data = &vendor_st,
2446 * ST-Ericsson derivative "PL023" (this is not
2447 * an official ARM number), this is a PL022 SSP block
2448 * stripped to SPI mode only, it has 32bit wide
2449 * and 32 locations deep TX/RX FIFO but no extended
2450 * CR0/CR1 register
2452 .id = 0x00080023,
2453 .mask = 0xffffffff,
2454 .data = &vendor_st_pl023,
2457 .id = 0x10080023,
2458 .mask = 0xffffffff,
2459 .data = &vendor_db5500_pl023,
2461 { 0, 0 },
2464 MODULE_DEVICE_TABLE(amba, pl022_ids);
2466 static struct amba_driver pl022_driver = {
2467 .drv = {
2468 .name = "ssp-pl022",
2469 .pm = &pl022_dev_pm_ops,
2471 .id_table = pl022_ids,
2472 .probe = pl022_probe,
2473 .remove = __devexit_p(pl022_remove),
2476 static int __init pl022_init(void)
2478 return amba_driver_register(&pl022_driver);
2480 subsys_initcall(pl022_init);
2482 static void __exit pl022_exit(void)
2484 amba_driver_unregister(&pl022_driver);
2486 module_exit(pl022_exit);
2488 MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2489 MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2490 MODULE_LICENSE("GPL");