Linux 4.2.1
[linux/fpc-iii.git] / drivers / spi / spi-pl022.c
blob94af80676684e4708d373e1551b8a6c46ea118fa
1 /*
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>
37 #include <linux/io.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))
63 #define DRIVE_TX 0
64 #define DO_NOT_DRIVE_TX 1
66 #define DO_NOT_QUEUE_DMA 0
67 #define QUEUE_DMA 1
69 #define RX_TRANSFER 1
70 #define TX_TRANSFER 2
73 * Macros to access SSP Registers with their offsets
75 #define SSP_CR0(r) (r + 0x000)
76 #define SSP_CR1(r) (r + 0x004)
77 #define SSP_DR(r) (r + 0x008)
78 #define SSP_SR(r) (r + 0x00C)
79 #define SSP_CPSR(r) (r + 0x010)
80 #define SSP_IMSC(r) (r + 0x014)
81 #define SSP_RIS(r) (r + 0x018)
82 #define SSP_MIS(r) (r + 0x01C)
83 #define SSP_ICR(r) (r + 0x020)
84 #define SSP_DMACR(r) (r + 0x024)
85 #define SSP_CSR(r) (r + 0x030) /* vendor extension */
86 #define SSP_ITCR(r) (r + 0x080)
87 #define SSP_ITIP(r) (r + 0x084)
88 #define SSP_ITOP(r) (r + 0x088)
89 #define SSP_TDR(r) (r + 0x08C)
91 #define SSP_PID0(r) (r + 0xFE0)
92 #define SSP_PID1(r) (r + 0xFE4)
93 #define SSP_PID2(r) (r + 0xFE8)
94 #define SSP_PID3(r) (r + 0xFEC)
96 #define SSP_CID0(r) (r + 0xFF0)
97 #define SSP_CID1(r) (r + 0xFF4)
98 #define SSP_CID2(r) (r + 0xFF8)
99 #define SSP_CID3(r) (r + 0xFFC)
102 * SSP Control Register 0 - SSP_CR0
104 #define SSP_CR0_MASK_DSS (0x0FUL << 0)
105 #define SSP_CR0_MASK_FRF (0x3UL << 4)
106 #define SSP_CR0_MASK_SPO (0x1UL << 6)
107 #define SSP_CR0_MASK_SPH (0x1UL << 7)
108 #define SSP_CR0_MASK_SCR (0xFFUL << 8)
111 * The ST version of this block moves som bits
112 * in SSP_CR0 and extends it to 32 bits
114 #define SSP_CR0_MASK_DSS_ST (0x1FUL << 0)
115 #define SSP_CR0_MASK_HALFDUP_ST (0x1UL << 5)
116 #define SSP_CR0_MASK_CSS_ST (0x1FUL << 16)
117 #define SSP_CR0_MASK_FRF_ST (0x3UL << 21)
120 * SSP Control Register 0 - SSP_CR1
122 #define SSP_CR1_MASK_LBM (0x1UL << 0)
123 #define SSP_CR1_MASK_SSE (0x1UL << 1)
124 #define SSP_CR1_MASK_MS (0x1UL << 2)
125 #define SSP_CR1_MASK_SOD (0x1UL << 3)
128 * The ST version of this block adds some bits
129 * in SSP_CR1
131 #define SSP_CR1_MASK_RENDN_ST (0x1UL << 4)
132 #define SSP_CR1_MASK_TENDN_ST (0x1UL << 5)
133 #define SSP_CR1_MASK_MWAIT_ST (0x1UL << 6)
134 #define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
135 #define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
136 /* This one is only in the PL023 variant */
137 #define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
140 * SSP Status Register - SSP_SR
142 #define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
143 #define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
144 #define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
145 #define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
146 #define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
149 * SSP Clock Prescale Register - SSP_CPSR
151 #define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
154 * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
156 #define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
157 #define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
158 #define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
159 #define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
162 * SSP Raw Interrupt Status Register - SSP_RIS
164 /* Receive Overrun Raw Interrupt status */
165 #define SSP_RIS_MASK_RORRIS (0x1UL << 0)
166 /* Receive Timeout Raw Interrupt status */
167 #define SSP_RIS_MASK_RTRIS (0x1UL << 1)
168 /* Receive FIFO Raw Interrupt status */
169 #define SSP_RIS_MASK_RXRIS (0x1UL << 2)
170 /* Transmit FIFO Raw Interrupt status */
171 #define SSP_RIS_MASK_TXRIS (0x1UL << 3)
174 * SSP Masked Interrupt Status Register - SSP_MIS
176 /* Receive Overrun Masked Interrupt status */
177 #define SSP_MIS_MASK_RORMIS (0x1UL << 0)
178 /* Receive Timeout Masked Interrupt status */
179 #define SSP_MIS_MASK_RTMIS (0x1UL << 1)
180 /* Receive FIFO Masked Interrupt status */
181 #define SSP_MIS_MASK_RXMIS (0x1UL << 2)
182 /* Transmit FIFO Masked Interrupt status */
183 #define SSP_MIS_MASK_TXMIS (0x1UL << 3)
186 * SSP Interrupt Clear Register - SSP_ICR
188 /* Receive Overrun Raw Clear Interrupt bit */
189 #define SSP_ICR_MASK_RORIC (0x1UL << 0)
190 /* Receive Timeout Clear Interrupt bit */
191 #define SSP_ICR_MASK_RTIC (0x1UL << 1)
194 * SSP DMA Control Register - SSP_DMACR
196 /* Receive DMA Enable bit */
197 #define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
198 /* Transmit DMA Enable bit */
199 #define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
202 * SSP Chip Select Control Register - SSP_CSR
203 * (vendor extension)
205 #define SSP_CSR_CSVALUE_MASK (0x1FUL << 0)
208 * SSP Integration Test control Register - SSP_ITCR
210 #define SSP_ITCR_MASK_ITEN (0x1UL << 0)
211 #define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
214 * SSP Integration Test Input Register - SSP_ITIP
216 #define ITIP_MASK_SSPRXD (0x1UL << 0)
217 #define ITIP_MASK_SSPFSSIN (0x1UL << 1)
218 #define ITIP_MASK_SSPCLKIN (0x1UL << 2)
219 #define ITIP_MASK_RXDMAC (0x1UL << 3)
220 #define ITIP_MASK_TXDMAC (0x1UL << 4)
221 #define ITIP_MASK_SSPTXDIN (0x1UL << 5)
224 * SSP Integration Test output Register - SSP_ITOP
226 #define ITOP_MASK_SSPTXD (0x1UL << 0)
227 #define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
228 #define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
229 #define ITOP_MASK_SSPOEn (0x1UL << 3)
230 #define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
231 #define ITOP_MASK_RORINTR (0x1UL << 5)
232 #define ITOP_MASK_RTINTR (0x1UL << 6)
233 #define ITOP_MASK_RXINTR (0x1UL << 7)
234 #define ITOP_MASK_TXINTR (0x1UL << 8)
235 #define ITOP_MASK_INTR (0x1UL << 9)
236 #define ITOP_MASK_RXDMABREQ (0x1UL << 10)
237 #define ITOP_MASK_RXDMASREQ (0x1UL << 11)
238 #define ITOP_MASK_TXDMABREQ (0x1UL << 12)
239 #define ITOP_MASK_TXDMASREQ (0x1UL << 13)
242 * SSP Test Data Register - SSP_TDR
244 #define TDR_MASK_TESTDATA (0xFFFFFFFF)
247 * Message State
248 * we use the spi_message.state (void *) pointer to
249 * hold a single state value, that's why all this
250 * (void *) casting is done here.
252 #define STATE_START ((void *) 0)
253 #define STATE_RUNNING ((void *) 1)
254 #define STATE_DONE ((void *) 2)
255 #define STATE_ERROR ((void *) -1)
258 * SSP State - Whether Enabled or Disabled
260 #define SSP_DISABLED (0)
261 #define SSP_ENABLED (1)
264 * SSP DMA State - Whether DMA Enabled or Disabled
266 #define SSP_DMA_DISABLED (0)
267 #define SSP_DMA_ENABLED (1)
270 * SSP Clock Defaults
272 #define SSP_DEFAULT_CLKRATE 0x2
273 #define SSP_DEFAULT_PRESCALE 0x40
276 * SSP Clock Parameter ranges
278 #define CPSDVR_MIN 0x02
279 #define CPSDVR_MAX 0xFE
280 #define SCR_MIN 0x00
281 #define SCR_MAX 0xFF
284 * SSP Interrupt related Macros
286 #define DEFAULT_SSP_REG_IMSC 0x0UL
287 #define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
288 #define ENABLE_ALL_INTERRUPTS ( \
289 SSP_IMSC_MASK_RORIM | \
290 SSP_IMSC_MASK_RTIM | \
291 SSP_IMSC_MASK_RXIM | \
292 SSP_IMSC_MASK_TXIM \
295 #define CLEAR_ALL_INTERRUPTS 0x3
297 #define SPI_POLLING_TIMEOUT 1000
300 * The type of reading going on on this chip
302 enum ssp_reading {
303 READING_NULL,
304 READING_U8,
305 READING_U16,
306 READING_U32
310 * The type of writing going on on this chip
312 enum ssp_writing {
313 WRITING_NULL,
314 WRITING_U8,
315 WRITING_U16,
316 WRITING_U32
320 * struct vendor_data - vendor-specific config parameters
321 * for PL022 derivates
322 * @fifodepth: depth of FIFOs (both)
323 * @max_bpw: maximum number of bits per word
324 * @unidir: supports unidirection transfers
325 * @extended_cr: 32 bit wide control register 0 with extra
326 * features and extra features in CR1 as found in the ST variants
327 * @pl023: supports a subset of the ST extensions called "PL023"
328 * @internal_cs_ctrl: supports chip select control register
330 struct vendor_data {
331 int fifodepth;
332 int max_bpw;
333 bool unidir;
334 bool extended_cr;
335 bool pl023;
336 bool loopback;
337 bool internal_cs_ctrl;
341 * struct pl022 - This is the private SSP driver data structure
342 * @adev: AMBA device model hookup
343 * @vendor: vendor data for the IP block
344 * @phybase: the physical memory where the SSP device resides
345 * @virtbase: the virtual memory where the SSP is mapped
346 * @clk: outgoing clock "SPICLK" for the SPI bus
347 * @master: SPI framework hookup
348 * @master_info: controller-specific data from machine setup
349 * @kworker: thread struct for message pump
350 * @kworker_task: pointer to task for message pump kworker thread
351 * @pump_messages: work struct for scheduling work to the message pump
352 * @queue_lock: spinlock to syncronise access to message queue
353 * @queue: message queue
354 * @busy: message pump is busy
355 * @running: message pump is running
356 * @pump_transfers: Tasklet used in Interrupt Transfer mode
357 * @cur_msg: Pointer to current spi_message being processed
358 * @cur_transfer: Pointer to current spi_transfer
359 * @cur_chip: pointer to current clients chip(assigned from controller_state)
360 * @next_msg_cs_active: the next message in the queue has been examined
361 * and it was found that it uses the same chip select as the previous
362 * message, so we left it active after the previous transfer, and it's
363 * active already.
364 * @tx: current position in TX buffer to be read
365 * @tx_end: end position in TX buffer to be read
366 * @rx: current position in RX buffer to be written
367 * @rx_end: end position in RX buffer to be written
368 * @read: the type of read currently going on
369 * @write: the type of write currently going on
370 * @exp_fifo_level: expected FIFO level
371 * @dma_rx_channel: optional channel for RX DMA
372 * @dma_tx_channel: optional channel for TX DMA
373 * @sgt_rx: scattertable for the RX transfer
374 * @sgt_tx: scattertable for the TX transfer
375 * @dummypage: a dummy page used for driving data on the bus with DMA
376 * @cur_cs: current chip select (gpio)
377 * @chipselects: list of chipselects (gpios)
379 struct pl022 {
380 struct amba_device *adev;
381 struct vendor_data *vendor;
382 resource_size_t phybase;
383 void __iomem *virtbase;
384 struct clk *clk;
385 struct spi_master *master;
386 struct pl022_ssp_controller *master_info;
387 /* Message per-transfer pump */
388 struct tasklet_struct pump_transfers;
389 struct spi_message *cur_msg;
390 struct spi_transfer *cur_transfer;
391 struct chip_data *cur_chip;
392 bool next_msg_cs_active;
393 void *tx;
394 void *tx_end;
395 void *rx;
396 void *rx_end;
397 enum ssp_reading read;
398 enum ssp_writing write;
399 u32 exp_fifo_level;
400 enum ssp_rx_level_trig rx_lev_trig;
401 enum ssp_tx_level_trig tx_lev_trig;
402 /* DMA settings */
403 #ifdef CONFIG_DMA_ENGINE
404 struct dma_chan *dma_rx_channel;
405 struct dma_chan *dma_tx_channel;
406 struct sg_table sgt_rx;
407 struct sg_table sgt_tx;
408 char *dummypage;
409 bool dma_running;
410 #endif
411 int cur_cs;
412 int *chipselects;
416 * struct chip_data - To maintain runtime state of SSP for each client chip
417 * @cr0: Value of control register CR0 of SSP - on later ST variants this
418 * register is 32 bits wide rather than just 16
419 * @cr1: Value of control register CR1 of SSP
420 * @dmacr: Value of DMA control Register of SSP
421 * @cpsr: Value of Clock prescale register
422 * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
423 * @enable_dma: Whether to enable DMA or not
424 * @read: function ptr to be used to read when doing xfer for this chip
425 * @write: function ptr to be used to write when doing xfer for this chip
426 * @cs_control: chip select callback provided by chip
427 * @xfer_type: polling/interrupt/DMA
429 * Runtime state of the SSP controller, maintained per chip,
430 * This would be set according to the current message that would be served
432 struct chip_data {
433 u32 cr0;
434 u16 cr1;
435 u16 dmacr;
436 u16 cpsr;
437 u8 n_bytes;
438 bool enable_dma;
439 enum ssp_reading read;
440 enum ssp_writing write;
441 void (*cs_control) (u32 command);
442 int xfer_type;
446 * null_cs_control - Dummy chip select function
447 * @command: select/delect the chip
449 * If no chip select function is provided by client this is used as dummy
450 * chip select
452 static void null_cs_control(u32 command)
454 pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
458 * internal_cs_control - Control chip select signals via SSP_CSR.
459 * @pl022: SSP driver private data structure
460 * @command: select/delect the chip
462 * Used on controller with internal chip select control via SSP_CSR register
463 * (vendor extension). Each of the 5 LSB in the register controls one chip
464 * select signal.
466 static void internal_cs_control(struct pl022 *pl022, u32 command)
468 u32 tmp;
470 tmp = readw(SSP_CSR(pl022->virtbase));
471 if (command == SSP_CHIP_SELECT)
472 tmp &= ~BIT(pl022->cur_cs);
473 else
474 tmp |= BIT(pl022->cur_cs);
475 writew(tmp, SSP_CSR(pl022->virtbase));
478 static void pl022_cs_control(struct pl022 *pl022, u32 command)
480 if (pl022->vendor->internal_cs_ctrl)
481 internal_cs_control(pl022, command);
482 else if (gpio_is_valid(pl022->cur_cs))
483 gpio_set_value(pl022->cur_cs, command);
484 else
485 pl022->cur_chip->cs_control(command);
489 * giveback - current spi_message is over, schedule next message and call
490 * callback of this message. Assumes that caller already
491 * set message->status; dma and pio irqs are blocked
492 * @pl022: SSP driver private data structure
494 static void giveback(struct pl022 *pl022)
496 struct spi_transfer *last_transfer;
497 pl022->next_msg_cs_active = false;
499 last_transfer = list_last_entry(&pl022->cur_msg->transfers,
500 struct spi_transfer, transfer_list);
502 /* Delay if requested before any change in chip select */
503 if (last_transfer->delay_usecs)
505 * FIXME: This runs in interrupt context.
506 * Is this really smart?
508 udelay(last_transfer->delay_usecs);
510 if (!last_transfer->cs_change) {
511 struct spi_message *next_msg;
514 * cs_change was not set. We can keep the chip select
515 * enabled if there is message in the queue and it is
516 * for the same spi device.
518 * We cannot postpone this until pump_messages, because
519 * after calling msg->complete (below) the driver that
520 * sent the current message could be unloaded, which
521 * could invalidate the cs_control() callback...
523 /* get a pointer to the next message, if any */
524 next_msg = spi_get_next_queued_message(pl022->master);
527 * see if the next and current messages point
528 * to the same spi device.
530 if (next_msg && next_msg->spi != pl022->cur_msg->spi)
531 next_msg = NULL;
532 if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
533 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
534 else
535 pl022->next_msg_cs_active = true;
539 pl022->cur_msg = NULL;
540 pl022->cur_transfer = NULL;
541 pl022->cur_chip = NULL;
543 /* disable the SPI/SSP operation */
544 writew((readw(SSP_CR1(pl022->virtbase)) &
545 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
547 spi_finalize_current_message(pl022->master);
551 * flush - flush the FIFO to reach a clean state
552 * @pl022: SSP driver private data structure
554 static int flush(struct pl022 *pl022)
556 unsigned long limit = loops_per_jiffy << 1;
558 dev_dbg(&pl022->adev->dev, "flush\n");
559 do {
560 while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
561 readw(SSP_DR(pl022->virtbase));
562 } while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
564 pl022->exp_fifo_level = 0;
566 return limit;
570 * restore_state - Load configuration of current chip
571 * @pl022: SSP driver private data structure
573 static void restore_state(struct pl022 *pl022)
575 struct chip_data *chip = pl022->cur_chip;
577 if (pl022->vendor->extended_cr)
578 writel(chip->cr0, SSP_CR0(pl022->virtbase));
579 else
580 writew(chip->cr0, SSP_CR0(pl022->virtbase));
581 writew(chip->cr1, SSP_CR1(pl022->virtbase));
582 writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
583 writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
584 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
585 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
589 * Default SSP Register Values
591 #define DEFAULT_SSP_REG_CR0 ( \
592 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
593 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
594 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
595 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
596 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
599 /* ST versions have slightly different bit layout */
600 #define DEFAULT_SSP_REG_CR0_ST ( \
601 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
602 GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
603 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
604 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
605 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
606 GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16) | \
607 GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
610 /* The PL023 version is slightly different again */
611 #define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
612 GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0) | \
613 GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
614 GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
615 GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
618 #define DEFAULT_SSP_REG_CR1 ( \
619 GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
620 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
621 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
622 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
625 /* ST versions extend this register to use all 16 bits */
626 #define DEFAULT_SSP_REG_CR1_ST ( \
627 DEFAULT_SSP_REG_CR1 | \
628 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
629 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
630 GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
631 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
632 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
636 * The PL023 variant has further differences: no loopback mode, no microwire
637 * support, and a new clock feedback delay setting.
639 #define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
640 GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
641 GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
642 GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
643 GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
644 GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
645 GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
646 GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
647 GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
650 #define DEFAULT_SSP_REG_CPSR ( \
651 GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
654 #define DEFAULT_SSP_REG_DMACR (\
655 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
656 GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
660 * load_ssp_default_config - Load default configuration for SSP
661 * @pl022: SSP driver private data structure
663 static void load_ssp_default_config(struct pl022 *pl022)
665 if (pl022->vendor->pl023) {
666 writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
667 writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
668 } else if (pl022->vendor->extended_cr) {
669 writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
670 writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
671 } else {
672 writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
673 writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
675 writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
676 writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
677 writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
678 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
682 * This will write to TX and read from RX according to the parameters
683 * set in pl022.
685 static void readwriter(struct pl022 *pl022)
689 * The FIFO depth is different between primecell variants.
690 * I believe filling in too much in the FIFO might cause
691 * errons in 8bit wide transfers on ARM variants (just 8 words
692 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
694 * To prevent this issue, the TX FIFO is only filled to the
695 * unused RX FIFO fill length, regardless of what the TX
696 * FIFO status flag indicates.
698 dev_dbg(&pl022->adev->dev,
699 "%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
700 __func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
702 /* Read as much as you can */
703 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
704 && (pl022->rx < pl022->rx_end)) {
705 switch (pl022->read) {
706 case READING_NULL:
707 readw(SSP_DR(pl022->virtbase));
708 break;
709 case READING_U8:
710 *(u8 *) (pl022->rx) =
711 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
712 break;
713 case READING_U16:
714 *(u16 *) (pl022->rx) =
715 (u16) readw(SSP_DR(pl022->virtbase));
716 break;
717 case READING_U32:
718 *(u32 *) (pl022->rx) =
719 readl(SSP_DR(pl022->virtbase));
720 break;
722 pl022->rx += (pl022->cur_chip->n_bytes);
723 pl022->exp_fifo_level--;
726 * Write as much as possible up to the RX FIFO size
728 while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
729 && (pl022->tx < pl022->tx_end)) {
730 switch (pl022->write) {
731 case WRITING_NULL:
732 writew(0x0, SSP_DR(pl022->virtbase));
733 break;
734 case WRITING_U8:
735 writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
736 break;
737 case WRITING_U16:
738 writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
739 break;
740 case WRITING_U32:
741 writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
742 break;
744 pl022->tx += (pl022->cur_chip->n_bytes);
745 pl022->exp_fifo_level++;
747 * This inner reader takes care of things appearing in the RX
748 * FIFO as we're transmitting. This will happen a lot since the
749 * clock starts running when you put things into the TX FIFO,
750 * and then things are continuously clocked into the RX FIFO.
752 while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
753 && (pl022->rx < pl022->rx_end)) {
754 switch (pl022->read) {
755 case READING_NULL:
756 readw(SSP_DR(pl022->virtbase));
757 break;
758 case READING_U8:
759 *(u8 *) (pl022->rx) =
760 readw(SSP_DR(pl022->virtbase)) & 0xFFU;
761 break;
762 case READING_U16:
763 *(u16 *) (pl022->rx) =
764 (u16) readw(SSP_DR(pl022->virtbase));
765 break;
766 case READING_U32:
767 *(u32 *) (pl022->rx) =
768 readl(SSP_DR(pl022->virtbase));
769 break;
771 pl022->rx += (pl022->cur_chip->n_bytes);
772 pl022->exp_fifo_level--;
776 * When we exit here the TX FIFO should be full and the RX FIFO
777 * should be empty
782 * next_transfer - Move to the Next transfer in the current spi message
783 * @pl022: SSP driver private data structure
785 * This function moves though the linked list of spi transfers in the
786 * current spi message and returns with the state of current spi
787 * message i.e whether its last transfer is done(STATE_DONE) or
788 * Next transfer is ready(STATE_RUNNING)
790 static void *next_transfer(struct pl022 *pl022)
792 struct spi_message *msg = pl022->cur_msg;
793 struct spi_transfer *trans = pl022->cur_transfer;
795 /* Move to next transfer */
796 if (trans->transfer_list.next != &msg->transfers) {
797 pl022->cur_transfer =
798 list_entry(trans->transfer_list.next,
799 struct spi_transfer, transfer_list);
800 return STATE_RUNNING;
802 return STATE_DONE;
806 * This DMA functionality is only compiled in if we have
807 * access to the generic DMA devices/DMA engine.
809 #ifdef CONFIG_DMA_ENGINE
810 static void unmap_free_dma_scatter(struct pl022 *pl022)
812 /* Unmap and free the SG tables */
813 dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
814 pl022->sgt_tx.nents, DMA_TO_DEVICE);
815 dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
816 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
817 sg_free_table(&pl022->sgt_rx);
818 sg_free_table(&pl022->sgt_tx);
821 static void dma_callback(void *data)
823 struct pl022 *pl022 = data;
824 struct spi_message *msg = pl022->cur_msg;
826 BUG_ON(!pl022->sgt_rx.sgl);
828 #ifdef VERBOSE_DEBUG
830 * Optionally dump out buffers to inspect contents, this is
831 * good if you want to convince yourself that the loopback
832 * read/write contents are the same, when adopting to a new
833 * DMA engine.
836 struct scatterlist *sg;
837 unsigned int i;
839 dma_sync_sg_for_cpu(&pl022->adev->dev,
840 pl022->sgt_rx.sgl,
841 pl022->sgt_rx.nents,
842 DMA_FROM_DEVICE);
844 for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
845 dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
846 print_hex_dump(KERN_ERR, "SPI RX: ",
847 DUMP_PREFIX_OFFSET,
850 sg_virt(sg),
851 sg_dma_len(sg),
854 for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
855 dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
856 print_hex_dump(KERN_ERR, "SPI TX: ",
857 DUMP_PREFIX_OFFSET,
860 sg_virt(sg),
861 sg_dma_len(sg),
865 #endif
867 unmap_free_dma_scatter(pl022);
869 /* Update total bytes transferred */
870 msg->actual_length += pl022->cur_transfer->len;
871 if (pl022->cur_transfer->cs_change)
872 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
874 /* Move to next transfer */
875 msg->state = next_transfer(pl022);
876 tasklet_schedule(&pl022->pump_transfers);
879 static void setup_dma_scatter(struct pl022 *pl022,
880 void *buffer,
881 unsigned int length,
882 struct sg_table *sgtab)
884 struct scatterlist *sg;
885 int bytesleft = length;
886 void *bufp = buffer;
887 int mapbytes;
888 int i;
890 if (buffer) {
891 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
893 * If there are less bytes left than what fits
894 * in the current page (plus page alignment offset)
895 * we just feed in this, else we stuff in as much
896 * as we can.
898 if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
899 mapbytes = bytesleft;
900 else
901 mapbytes = PAGE_SIZE - offset_in_page(bufp);
902 sg_set_page(sg, virt_to_page(bufp),
903 mapbytes, offset_in_page(bufp));
904 bufp += mapbytes;
905 bytesleft -= mapbytes;
906 dev_dbg(&pl022->adev->dev,
907 "set RX/TX target page @ %p, %d bytes, %d left\n",
908 bufp, mapbytes, bytesleft);
910 } else {
911 /* Map the dummy buffer on every page */
912 for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
913 if (bytesleft < PAGE_SIZE)
914 mapbytes = bytesleft;
915 else
916 mapbytes = PAGE_SIZE;
917 sg_set_page(sg, virt_to_page(pl022->dummypage),
918 mapbytes, 0);
919 bytesleft -= mapbytes;
920 dev_dbg(&pl022->adev->dev,
921 "set RX/TX to dummy page %d bytes, %d left\n",
922 mapbytes, bytesleft);
926 BUG_ON(bytesleft);
930 * configure_dma - configures the channels for the next transfer
931 * @pl022: SSP driver's private data structure
933 static int configure_dma(struct pl022 *pl022)
935 struct dma_slave_config rx_conf = {
936 .src_addr = SSP_DR(pl022->phybase),
937 .direction = DMA_DEV_TO_MEM,
938 .device_fc = false,
940 struct dma_slave_config tx_conf = {
941 .dst_addr = SSP_DR(pl022->phybase),
942 .direction = DMA_MEM_TO_DEV,
943 .device_fc = false,
945 unsigned int pages;
946 int ret;
947 int rx_sglen, tx_sglen;
948 struct dma_chan *rxchan = pl022->dma_rx_channel;
949 struct dma_chan *txchan = pl022->dma_tx_channel;
950 struct dma_async_tx_descriptor *rxdesc;
951 struct dma_async_tx_descriptor *txdesc;
953 /* Check that the channels are available */
954 if (!rxchan || !txchan)
955 return -ENODEV;
958 * If supplied, the DMA burstsize should equal the FIFO trigger level.
959 * Notice that the DMA engine uses one-to-one mapping. Since we can
960 * not trigger on 2 elements this needs explicit mapping rather than
961 * calculation.
963 switch (pl022->rx_lev_trig) {
964 case SSP_RX_1_OR_MORE_ELEM:
965 rx_conf.src_maxburst = 1;
966 break;
967 case SSP_RX_4_OR_MORE_ELEM:
968 rx_conf.src_maxburst = 4;
969 break;
970 case SSP_RX_8_OR_MORE_ELEM:
971 rx_conf.src_maxburst = 8;
972 break;
973 case SSP_RX_16_OR_MORE_ELEM:
974 rx_conf.src_maxburst = 16;
975 break;
976 case SSP_RX_32_OR_MORE_ELEM:
977 rx_conf.src_maxburst = 32;
978 break;
979 default:
980 rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
981 break;
984 switch (pl022->tx_lev_trig) {
985 case SSP_TX_1_OR_MORE_EMPTY_LOC:
986 tx_conf.dst_maxburst = 1;
987 break;
988 case SSP_TX_4_OR_MORE_EMPTY_LOC:
989 tx_conf.dst_maxburst = 4;
990 break;
991 case SSP_TX_8_OR_MORE_EMPTY_LOC:
992 tx_conf.dst_maxburst = 8;
993 break;
994 case SSP_TX_16_OR_MORE_EMPTY_LOC:
995 tx_conf.dst_maxburst = 16;
996 break;
997 case SSP_TX_32_OR_MORE_EMPTY_LOC:
998 tx_conf.dst_maxburst = 32;
999 break;
1000 default:
1001 tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
1002 break;
1005 switch (pl022->read) {
1006 case READING_NULL:
1007 /* Use the same as for writing */
1008 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1009 break;
1010 case READING_U8:
1011 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1012 break;
1013 case READING_U16:
1014 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1015 break;
1016 case READING_U32:
1017 rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1018 break;
1021 switch (pl022->write) {
1022 case WRITING_NULL:
1023 /* Use the same as for reading */
1024 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
1025 break;
1026 case WRITING_U8:
1027 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1028 break;
1029 case WRITING_U16:
1030 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1031 break;
1032 case WRITING_U32:
1033 tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1034 break;
1037 /* SPI pecularity: we need to read and write the same width */
1038 if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1039 rx_conf.src_addr_width = tx_conf.dst_addr_width;
1040 if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1041 tx_conf.dst_addr_width = rx_conf.src_addr_width;
1042 BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
1044 dmaengine_slave_config(rxchan, &rx_conf);
1045 dmaengine_slave_config(txchan, &tx_conf);
1047 /* Create sglists for the transfers */
1048 pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
1049 dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
1051 ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
1052 if (ret)
1053 goto err_alloc_rx_sg;
1055 ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
1056 if (ret)
1057 goto err_alloc_tx_sg;
1059 /* Fill in the scatterlists for the RX+TX buffers */
1060 setup_dma_scatter(pl022, pl022->rx,
1061 pl022->cur_transfer->len, &pl022->sgt_rx);
1062 setup_dma_scatter(pl022, pl022->tx,
1063 pl022->cur_transfer->len, &pl022->sgt_tx);
1065 /* Map DMA buffers */
1066 rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1067 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1068 if (!rx_sglen)
1069 goto err_rx_sgmap;
1071 tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1072 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1073 if (!tx_sglen)
1074 goto err_tx_sgmap;
1076 /* Send both scatterlists */
1077 rxdesc = dmaengine_prep_slave_sg(rxchan,
1078 pl022->sgt_rx.sgl,
1079 rx_sglen,
1080 DMA_DEV_TO_MEM,
1081 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1082 if (!rxdesc)
1083 goto err_rxdesc;
1085 txdesc = dmaengine_prep_slave_sg(txchan,
1086 pl022->sgt_tx.sgl,
1087 tx_sglen,
1088 DMA_MEM_TO_DEV,
1089 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1090 if (!txdesc)
1091 goto err_txdesc;
1093 /* Put the callback on the RX transfer only, that should finish last */
1094 rxdesc->callback = dma_callback;
1095 rxdesc->callback_param = pl022;
1097 /* Submit and fire RX and TX with TX last so we're ready to read! */
1098 dmaengine_submit(rxdesc);
1099 dmaengine_submit(txdesc);
1100 dma_async_issue_pending(rxchan);
1101 dma_async_issue_pending(txchan);
1102 pl022->dma_running = true;
1104 return 0;
1106 err_txdesc:
1107 dmaengine_terminate_all(txchan);
1108 err_rxdesc:
1109 dmaengine_terminate_all(rxchan);
1110 dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1111 pl022->sgt_tx.nents, DMA_TO_DEVICE);
1112 err_tx_sgmap:
1113 dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1114 pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1115 err_rx_sgmap:
1116 sg_free_table(&pl022->sgt_tx);
1117 err_alloc_tx_sg:
1118 sg_free_table(&pl022->sgt_rx);
1119 err_alloc_rx_sg:
1120 return -ENOMEM;
1123 static int pl022_dma_probe(struct pl022 *pl022)
1125 dma_cap_mask_t mask;
1127 /* Try to acquire a generic DMA engine slave channel */
1128 dma_cap_zero(mask);
1129 dma_cap_set(DMA_SLAVE, mask);
1131 * We need both RX and TX channels to do DMA, else do none
1132 * of them.
1134 pl022->dma_rx_channel = dma_request_channel(mask,
1135 pl022->master_info->dma_filter,
1136 pl022->master_info->dma_rx_param);
1137 if (!pl022->dma_rx_channel) {
1138 dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1139 goto err_no_rxchan;
1142 pl022->dma_tx_channel = dma_request_channel(mask,
1143 pl022->master_info->dma_filter,
1144 pl022->master_info->dma_tx_param);
1145 if (!pl022->dma_tx_channel) {
1146 dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1147 goto err_no_txchan;
1150 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1151 if (!pl022->dummypage)
1152 goto err_no_dummypage;
1154 dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1155 dma_chan_name(pl022->dma_rx_channel),
1156 dma_chan_name(pl022->dma_tx_channel));
1158 return 0;
1160 err_no_dummypage:
1161 dma_release_channel(pl022->dma_tx_channel);
1162 err_no_txchan:
1163 dma_release_channel(pl022->dma_rx_channel);
1164 pl022->dma_rx_channel = NULL;
1165 err_no_rxchan:
1166 dev_err(&pl022->adev->dev,
1167 "Failed to work in dma mode, work without dma!\n");
1168 return -ENODEV;
1171 static int pl022_dma_autoprobe(struct pl022 *pl022)
1173 struct device *dev = &pl022->adev->dev;
1175 /* automatically configure DMA channels from platform, normally using DT */
1176 pl022->dma_rx_channel = dma_request_slave_channel(dev, "rx");
1177 if (!pl022->dma_rx_channel)
1178 goto err_no_rxchan;
1180 pl022->dma_tx_channel = dma_request_slave_channel(dev, "tx");
1181 if (!pl022->dma_tx_channel)
1182 goto err_no_txchan;
1184 pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1185 if (!pl022->dummypage)
1186 goto err_no_dummypage;
1188 return 0;
1190 err_no_dummypage:
1191 dma_release_channel(pl022->dma_tx_channel);
1192 pl022->dma_tx_channel = NULL;
1193 err_no_txchan:
1194 dma_release_channel(pl022->dma_rx_channel);
1195 pl022->dma_rx_channel = NULL;
1196 err_no_rxchan:
1197 return -ENODEV;
1200 static void terminate_dma(struct pl022 *pl022)
1202 struct dma_chan *rxchan = pl022->dma_rx_channel;
1203 struct dma_chan *txchan = pl022->dma_tx_channel;
1205 dmaengine_terminate_all(rxchan);
1206 dmaengine_terminate_all(txchan);
1207 unmap_free_dma_scatter(pl022);
1208 pl022->dma_running = false;
1211 static void pl022_dma_remove(struct pl022 *pl022)
1213 if (pl022->dma_running)
1214 terminate_dma(pl022);
1215 if (pl022->dma_tx_channel)
1216 dma_release_channel(pl022->dma_tx_channel);
1217 if (pl022->dma_rx_channel)
1218 dma_release_channel(pl022->dma_rx_channel);
1219 kfree(pl022->dummypage);
1222 #else
1223 static inline int configure_dma(struct pl022 *pl022)
1225 return -ENODEV;
1228 static inline int pl022_dma_autoprobe(struct pl022 *pl022)
1230 return 0;
1233 static inline int pl022_dma_probe(struct pl022 *pl022)
1235 return 0;
1238 static inline void pl022_dma_remove(struct pl022 *pl022)
1241 #endif
1244 * pl022_interrupt_handler - Interrupt handler for SSP controller
1246 * This function handles interrupts generated for an interrupt based transfer.
1247 * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1248 * current message's state as STATE_ERROR and schedule the tasklet
1249 * pump_transfers which will do the postprocessing of the current message by
1250 * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1251 * more data, and writes data in TX FIFO till it is not full. If we complete
1252 * the transfer we move to the next transfer and schedule the tasklet.
1254 static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1256 struct pl022 *pl022 = dev_id;
1257 struct spi_message *msg = pl022->cur_msg;
1258 u16 irq_status = 0;
1260 if (unlikely(!msg)) {
1261 dev_err(&pl022->adev->dev,
1262 "bad message state in interrupt handler");
1263 /* Never fail */
1264 return IRQ_HANDLED;
1267 /* Read the Interrupt Status Register */
1268 irq_status = readw(SSP_MIS(pl022->virtbase));
1270 if (unlikely(!irq_status))
1271 return IRQ_NONE;
1274 * This handles the FIFO interrupts, the timeout
1275 * interrupts are flatly ignored, they cannot be
1276 * trusted.
1278 if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1280 * Overrun interrupt - bail out since our Data has been
1281 * corrupted
1283 dev_err(&pl022->adev->dev, "FIFO overrun\n");
1284 if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1285 dev_err(&pl022->adev->dev,
1286 "RXFIFO is full\n");
1289 * Disable and clear interrupts, disable SSP,
1290 * mark message with bad status so it can be
1291 * retried.
1293 writew(DISABLE_ALL_INTERRUPTS,
1294 SSP_IMSC(pl022->virtbase));
1295 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1296 writew((readw(SSP_CR1(pl022->virtbase)) &
1297 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1298 msg->state = STATE_ERROR;
1300 /* Schedule message queue handler */
1301 tasklet_schedule(&pl022->pump_transfers);
1302 return IRQ_HANDLED;
1305 readwriter(pl022);
1307 if (pl022->tx == pl022->tx_end) {
1308 /* Disable Transmit interrupt, enable receive interrupt */
1309 writew((readw(SSP_IMSC(pl022->virtbase)) &
1310 ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1311 SSP_IMSC(pl022->virtbase));
1315 * Since all transactions must write as much as shall be read,
1316 * we can conclude the entire transaction once RX is complete.
1317 * At this point, all TX will always be finished.
1319 if (pl022->rx >= pl022->rx_end) {
1320 writew(DISABLE_ALL_INTERRUPTS,
1321 SSP_IMSC(pl022->virtbase));
1322 writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1323 if (unlikely(pl022->rx > pl022->rx_end)) {
1324 dev_warn(&pl022->adev->dev, "read %u surplus "
1325 "bytes (did you request an odd "
1326 "number of bytes on a 16bit bus?)\n",
1327 (u32) (pl022->rx - pl022->rx_end));
1329 /* Update total bytes transferred */
1330 msg->actual_length += pl022->cur_transfer->len;
1331 if (pl022->cur_transfer->cs_change)
1332 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1333 /* Move to next transfer */
1334 msg->state = next_transfer(pl022);
1335 tasklet_schedule(&pl022->pump_transfers);
1336 return IRQ_HANDLED;
1339 return IRQ_HANDLED;
1343 * This sets up the pointers to memory for the next message to
1344 * send out on the SPI bus.
1346 static int set_up_next_transfer(struct pl022 *pl022,
1347 struct spi_transfer *transfer)
1349 int residue;
1351 /* Sanity check the message for this bus width */
1352 residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1353 if (unlikely(residue != 0)) {
1354 dev_err(&pl022->adev->dev,
1355 "message of %u bytes to transmit but the current "
1356 "chip bus has a data width of %u bytes!\n",
1357 pl022->cur_transfer->len,
1358 pl022->cur_chip->n_bytes);
1359 dev_err(&pl022->adev->dev, "skipping this message\n");
1360 return -EIO;
1362 pl022->tx = (void *)transfer->tx_buf;
1363 pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1364 pl022->rx = (void *)transfer->rx_buf;
1365 pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1366 pl022->write =
1367 pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1368 pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1369 return 0;
1373 * pump_transfers - Tasklet function which schedules next transfer
1374 * when running in interrupt or DMA transfer mode.
1375 * @data: SSP driver private data structure
1378 static void pump_transfers(unsigned long data)
1380 struct pl022 *pl022 = (struct pl022 *) data;
1381 struct spi_message *message = NULL;
1382 struct spi_transfer *transfer = NULL;
1383 struct spi_transfer *previous = NULL;
1385 /* Get current state information */
1386 message = pl022->cur_msg;
1387 transfer = pl022->cur_transfer;
1389 /* Handle for abort */
1390 if (message->state == STATE_ERROR) {
1391 message->status = -EIO;
1392 giveback(pl022);
1393 return;
1396 /* Handle end of message */
1397 if (message->state == STATE_DONE) {
1398 message->status = 0;
1399 giveback(pl022);
1400 return;
1403 /* Delay if requested at end of transfer before CS change */
1404 if (message->state == STATE_RUNNING) {
1405 previous = list_entry(transfer->transfer_list.prev,
1406 struct spi_transfer,
1407 transfer_list);
1408 if (previous->delay_usecs)
1410 * FIXME: This runs in interrupt context.
1411 * Is this really smart?
1413 udelay(previous->delay_usecs);
1415 /* Reselect chip select only if cs_change was requested */
1416 if (previous->cs_change)
1417 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1418 } else {
1419 /* STATE_START */
1420 message->state = STATE_RUNNING;
1423 if (set_up_next_transfer(pl022, transfer)) {
1424 message->state = STATE_ERROR;
1425 message->status = -EIO;
1426 giveback(pl022);
1427 return;
1429 /* Flush the FIFOs and let's go! */
1430 flush(pl022);
1432 if (pl022->cur_chip->enable_dma) {
1433 if (configure_dma(pl022)) {
1434 dev_dbg(&pl022->adev->dev,
1435 "configuration of DMA failed, fall back to interrupt mode\n");
1436 goto err_config_dma;
1438 return;
1441 err_config_dma:
1442 /* enable all interrupts except RX */
1443 writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
1446 static void do_interrupt_dma_transfer(struct pl022 *pl022)
1449 * Default is to enable all interrupts except RX -
1450 * this will be enabled once TX is complete
1452 u32 irqflags = (u32)(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM);
1454 /* Enable target chip, if not already active */
1455 if (!pl022->next_msg_cs_active)
1456 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1458 if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
1459 /* Error path */
1460 pl022->cur_msg->state = STATE_ERROR;
1461 pl022->cur_msg->status = -EIO;
1462 giveback(pl022);
1463 return;
1465 /* If we're using DMA, set up DMA here */
1466 if (pl022->cur_chip->enable_dma) {
1467 /* Configure DMA transfer */
1468 if (configure_dma(pl022)) {
1469 dev_dbg(&pl022->adev->dev,
1470 "configuration of DMA failed, fall back to interrupt mode\n");
1471 goto err_config_dma;
1473 /* Disable interrupts in DMA mode, IRQ from DMA controller */
1474 irqflags = DISABLE_ALL_INTERRUPTS;
1476 err_config_dma:
1477 /* Enable SSP, turn on interrupts */
1478 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1479 SSP_CR1(pl022->virtbase));
1480 writew(irqflags, SSP_IMSC(pl022->virtbase));
1483 static void do_polling_transfer(struct pl022 *pl022)
1485 struct spi_message *message = NULL;
1486 struct spi_transfer *transfer = NULL;
1487 struct spi_transfer *previous = NULL;
1488 struct chip_data *chip;
1489 unsigned long time, timeout;
1491 chip = pl022->cur_chip;
1492 message = pl022->cur_msg;
1494 while (message->state != STATE_DONE) {
1495 /* Handle for abort */
1496 if (message->state == STATE_ERROR)
1497 break;
1498 transfer = pl022->cur_transfer;
1500 /* Delay if requested at end of transfer */
1501 if (message->state == STATE_RUNNING) {
1502 previous =
1503 list_entry(transfer->transfer_list.prev,
1504 struct spi_transfer, transfer_list);
1505 if (previous->delay_usecs)
1506 udelay(previous->delay_usecs);
1507 if (previous->cs_change)
1508 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1509 } else {
1510 /* STATE_START */
1511 message->state = STATE_RUNNING;
1512 if (!pl022->next_msg_cs_active)
1513 pl022_cs_control(pl022, SSP_CHIP_SELECT);
1516 /* Configuration Changing Per Transfer */
1517 if (set_up_next_transfer(pl022, transfer)) {
1518 /* Error path */
1519 message->state = STATE_ERROR;
1520 break;
1522 /* Flush FIFOs and enable SSP */
1523 flush(pl022);
1524 writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1525 SSP_CR1(pl022->virtbase));
1527 dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1529 timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1530 while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1531 time = jiffies;
1532 readwriter(pl022);
1533 if (time_after(time, timeout)) {
1534 dev_warn(&pl022->adev->dev,
1535 "%s: timeout!\n", __func__);
1536 message->state = STATE_ERROR;
1537 goto out;
1539 cpu_relax();
1542 /* Update total byte transferred */
1543 message->actual_length += pl022->cur_transfer->len;
1544 if (pl022->cur_transfer->cs_change)
1545 pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1546 /* Move to next transfer */
1547 message->state = next_transfer(pl022);
1549 out:
1550 /* Handle end of message */
1551 if (message->state == STATE_DONE)
1552 message->status = 0;
1553 else
1554 message->status = -EIO;
1556 giveback(pl022);
1557 return;
1560 static int pl022_transfer_one_message(struct spi_master *master,
1561 struct spi_message *msg)
1563 struct pl022 *pl022 = spi_master_get_devdata(master);
1565 /* Initial message state */
1566 pl022->cur_msg = msg;
1567 msg->state = STATE_START;
1569 pl022->cur_transfer = list_entry(msg->transfers.next,
1570 struct spi_transfer, transfer_list);
1572 /* Setup the SPI using the per chip configuration */
1573 pl022->cur_chip = spi_get_ctldata(msg->spi);
1574 pl022->cur_cs = pl022->chipselects[msg->spi->chip_select];
1576 restore_state(pl022);
1577 flush(pl022);
1579 if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1580 do_polling_transfer(pl022);
1581 else
1582 do_interrupt_dma_transfer(pl022);
1584 return 0;
1587 static int pl022_unprepare_transfer_hardware(struct spi_master *master)
1589 struct pl022 *pl022 = spi_master_get_devdata(master);
1591 /* nothing more to do - disable spi/ssp and power off */
1592 writew((readw(SSP_CR1(pl022->virtbase)) &
1593 (~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1595 return 0;
1598 static int verify_controller_parameters(struct pl022 *pl022,
1599 struct pl022_config_chip const *chip_info)
1601 if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1602 || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1603 dev_err(&pl022->adev->dev,
1604 "interface is configured incorrectly\n");
1605 return -EINVAL;
1607 if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1608 (!pl022->vendor->unidir)) {
1609 dev_err(&pl022->adev->dev,
1610 "unidirectional mode not supported in this "
1611 "hardware version\n");
1612 return -EINVAL;
1614 if ((chip_info->hierarchy != SSP_MASTER)
1615 && (chip_info->hierarchy != SSP_SLAVE)) {
1616 dev_err(&pl022->adev->dev,
1617 "hierarchy is configured incorrectly\n");
1618 return -EINVAL;
1620 if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1621 && (chip_info->com_mode != DMA_TRANSFER)
1622 && (chip_info->com_mode != POLLING_TRANSFER)) {
1623 dev_err(&pl022->adev->dev,
1624 "Communication mode is configured incorrectly\n");
1625 return -EINVAL;
1627 switch (chip_info->rx_lev_trig) {
1628 case SSP_RX_1_OR_MORE_ELEM:
1629 case SSP_RX_4_OR_MORE_ELEM:
1630 case SSP_RX_8_OR_MORE_ELEM:
1631 /* These are always OK, all variants can handle this */
1632 break;
1633 case SSP_RX_16_OR_MORE_ELEM:
1634 if (pl022->vendor->fifodepth < 16) {
1635 dev_err(&pl022->adev->dev,
1636 "RX FIFO Trigger Level is configured incorrectly\n");
1637 return -EINVAL;
1639 break;
1640 case SSP_RX_32_OR_MORE_ELEM:
1641 if (pl022->vendor->fifodepth < 32) {
1642 dev_err(&pl022->adev->dev,
1643 "RX FIFO Trigger Level is configured incorrectly\n");
1644 return -EINVAL;
1646 break;
1647 default:
1648 dev_err(&pl022->adev->dev,
1649 "RX FIFO Trigger Level is configured incorrectly\n");
1650 return -EINVAL;
1652 switch (chip_info->tx_lev_trig) {
1653 case SSP_TX_1_OR_MORE_EMPTY_LOC:
1654 case SSP_TX_4_OR_MORE_EMPTY_LOC:
1655 case SSP_TX_8_OR_MORE_EMPTY_LOC:
1656 /* These are always OK, all variants can handle this */
1657 break;
1658 case SSP_TX_16_OR_MORE_EMPTY_LOC:
1659 if (pl022->vendor->fifodepth < 16) {
1660 dev_err(&pl022->adev->dev,
1661 "TX FIFO Trigger Level is configured incorrectly\n");
1662 return -EINVAL;
1664 break;
1665 case SSP_TX_32_OR_MORE_EMPTY_LOC:
1666 if (pl022->vendor->fifodepth < 32) {
1667 dev_err(&pl022->adev->dev,
1668 "TX FIFO Trigger Level is configured incorrectly\n");
1669 return -EINVAL;
1671 break;
1672 default:
1673 dev_err(&pl022->adev->dev,
1674 "TX FIFO Trigger Level is configured incorrectly\n");
1675 return -EINVAL;
1677 if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1678 if ((chip_info->ctrl_len < SSP_BITS_4)
1679 || (chip_info->ctrl_len > SSP_BITS_32)) {
1680 dev_err(&pl022->adev->dev,
1681 "CTRL LEN is configured incorrectly\n");
1682 return -EINVAL;
1684 if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1685 && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1686 dev_err(&pl022->adev->dev,
1687 "Wait State is configured incorrectly\n");
1688 return -EINVAL;
1690 /* Half duplex is only available in the ST Micro version */
1691 if (pl022->vendor->extended_cr) {
1692 if ((chip_info->duplex !=
1693 SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1694 && (chip_info->duplex !=
1695 SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1696 dev_err(&pl022->adev->dev,
1697 "Microwire duplex mode is configured incorrectly\n");
1698 return -EINVAL;
1700 } else {
1701 if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1702 dev_err(&pl022->adev->dev,
1703 "Microwire half duplex mode requested,"
1704 " but this is only available in the"
1705 " ST version of PL022\n");
1706 return -EINVAL;
1709 return 0;
1712 static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1714 return rate / (cpsdvsr * (1 + scr));
1717 static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1718 ssp_clock_params * clk_freq)
1720 /* Lets calculate the frequency parameters */
1721 u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1722 u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1723 best_scr = 0, tmp, found = 0;
1725 rate = clk_get_rate(pl022->clk);
1726 /* cpsdvscr = 2 & scr 0 */
1727 max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1728 /* cpsdvsr = 254 & scr = 255 */
1729 min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1731 if (freq > max_tclk)
1732 dev_warn(&pl022->adev->dev,
1733 "Max speed that can be programmed is %d Hz, you requested %d\n",
1734 max_tclk, freq);
1736 if (freq < min_tclk) {
1737 dev_err(&pl022->adev->dev,
1738 "Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1739 freq, min_tclk);
1740 return -EINVAL;
1744 * best_freq will give closest possible available rate (<= requested
1745 * freq) for all values of scr & cpsdvsr.
1747 while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1748 while (scr <= SCR_MAX) {
1749 tmp = spi_rate(rate, cpsdvsr, scr);
1751 if (tmp > freq) {
1752 /* we need lower freq */
1753 scr++;
1754 continue;
1758 * If found exact value, mark found and break.
1759 * If found more closer value, update and break.
1761 if (tmp > best_freq) {
1762 best_freq = tmp;
1763 best_cpsdvsr = cpsdvsr;
1764 best_scr = scr;
1766 if (tmp == freq)
1767 found = 1;
1770 * increased scr will give lower rates, which are not
1771 * required
1773 break;
1775 cpsdvsr += 2;
1776 scr = SCR_MIN;
1779 WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1780 freq);
1782 clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1783 clk_freq->scr = (u8) (best_scr & 0xFF);
1784 dev_dbg(&pl022->adev->dev,
1785 "SSP Target Frequency is: %u, Effective Frequency is %u\n",
1786 freq, best_freq);
1787 dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1788 clk_freq->cpsdvsr, clk_freq->scr);
1790 return 0;
1794 * A piece of default chip info unless the platform
1795 * supplies it.
1797 static const struct pl022_config_chip pl022_default_chip_info = {
1798 .com_mode = POLLING_TRANSFER,
1799 .iface = SSP_INTERFACE_MOTOROLA_SPI,
1800 .hierarchy = SSP_SLAVE,
1801 .slave_tx_disable = DO_NOT_DRIVE_TX,
1802 .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1803 .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1804 .ctrl_len = SSP_BITS_8,
1805 .wait_state = SSP_MWIRE_WAIT_ZERO,
1806 .duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1807 .cs_control = null_cs_control,
1811 * pl022_setup - setup function registered to SPI master framework
1812 * @spi: spi device which is requesting setup
1814 * This function is registered to the SPI framework for this SPI master
1815 * controller. If it is the first time when setup is called by this device,
1816 * this function will initialize the runtime state for this chip and save
1817 * the same in the device structure. Else it will update the runtime info
1818 * with the updated chip info. Nothing is really being written to the
1819 * controller hardware here, that is not done until the actual transfer
1820 * commence.
1822 static int pl022_setup(struct spi_device *spi)
1824 struct pl022_config_chip const *chip_info;
1825 struct pl022_config_chip chip_info_dt;
1826 struct chip_data *chip;
1827 struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1828 int status = 0;
1829 struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1830 unsigned int bits = spi->bits_per_word;
1831 u32 tmp;
1832 struct device_node *np = spi->dev.of_node;
1834 if (!spi->max_speed_hz)
1835 return -EINVAL;
1837 /* Get controller_state if one is supplied */
1838 chip = spi_get_ctldata(spi);
1840 if (chip == NULL) {
1841 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1842 if (!chip)
1843 return -ENOMEM;
1844 dev_dbg(&spi->dev,
1845 "allocated memory for controller's runtime state\n");
1848 /* Get controller data if one is supplied */
1849 chip_info = spi->controller_data;
1851 if (chip_info == NULL) {
1852 if (np) {
1853 chip_info_dt = pl022_default_chip_info;
1855 chip_info_dt.hierarchy = SSP_MASTER;
1856 of_property_read_u32(np, "pl022,interface",
1857 &chip_info_dt.iface);
1858 of_property_read_u32(np, "pl022,com-mode",
1859 &chip_info_dt.com_mode);
1860 of_property_read_u32(np, "pl022,rx-level-trig",
1861 &chip_info_dt.rx_lev_trig);
1862 of_property_read_u32(np, "pl022,tx-level-trig",
1863 &chip_info_dt.tx_lev_trig);
1864 of_property_read_u32(np, "pl022,ctrl-len",
1865 &chip_info_dt.ctrl_len);
1866 of_property_read_u32(np, "pl022,wait-state",
1867 &chip_info_dt.wait_state);
1868 of_property_read_u32(np, "pl022,duplex",
1869 &chip_info_dt.duplex);
1871 chip_info = &chip_info_dt;
1872 } else {
1873 chip_info = &pl022_default_chip_info;
1874 /* spi_board_info.controller_data not is supplied */
1875 dev_dbg(&spi->dev,
1876 "using default controller_data settings\n");
1878 } else
1879 dev_dbg(&spi->dev,
1880 "using user supplied controller_data settings\n");
1883 * We can override with custom divisors, else we use the board
1884 * frequency setting
1886 if ((0 == chip_info->clk_freq.cpsdvsr)
1887 && (0 == chip_info->clk_freq.scr)) {
1888 status = calculate_effective_freq(pl022,
1889 spi->max_speed_hz,
1890 &clk_freq);
1891 if (status < 0)
1892 goto err_config_params;
1893 } else {
1894 memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1895 if ((clk_freq.cpsdvsr % 2) != 0)
1896 clk_freq.cpsdvsr =
1897 clk_freq.cpsdvsr - 1;
1899 if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1900 || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1901 status = -EINVAL;
1902 dev_err(&spi->dev,
1903 "cpsdvsr is configured incorrectly\n");
1904 goto err_config_params;
1907 status = verify_controller_parameters(pl022, chip_info);
1908 if (status) {
1909 dev_err(&spi->dev, "controller data is incorrect");
1910 goto err_config_params;
1913 pl022->rx_lev_trig = chip_info->rx_lev_trig;
1914 pl022->tx_lev_trig = chip_info->tx_lev_trig;
1916 /* Now set controller state based on controller data */
1917 chip->xfer_type = chip_info->com_mode;
1918 if (!chip_info->cs_control) {
1919 chip->cs_control = null_cs_control;
1920 if (!gpio_is_valid(pl022->chipselects[spi->chip_select]))
1921 dev_warn(&spi->dev,
1922 "invalid chip select\n");
1923 } else
1924 chip->cs_control = chip_info->cs_control;
1926 /* Check bits per word with vendor specific range */
1927 if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
1928 status = -ENOTSUPP;
1929 dev_err(&spi->dev, "illegal data size for this controller!\n");
1930 dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
1931 pl022->vendor->max_bpw);
1932 goto err_config_params;
1933 } else if (bits <= 8) {
1934 dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1935 chip->n_bytes = 1;
1936 chip->read = READING_U8;
1937 chip->write = WRITING_U8;
1938 } else if (bits <= 16) {
1939 dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1940 chip->n_bytes = 2;
1941 chip->read = READING_U16;
1942 chip->write = WRITING_U16;
1943 } else {
1944 dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1945 chip->n_bytes = 4;
1946 chip->read = READING_U32;
1947 chip->write = WRITING_U32;
1950 /* Now Initialize all register settings required for this chip */
1951 chip->cr0 = 0;
1952 chip->cr1 = 0;
1953 chip->dmacr = 0;
1954 chip->cpsr = 0;
1955 if ((chip_info->com_mode == DMA_TRANSFER)
1956 && ((pl022->master_info)->enable_dma)) {
1957 chip->enable_dma = true;
1958 dev_dbg(&spi->dev, "DMA mode set in controller state\n");
1959 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1960 SSP_DMACR_MASK_RXDMAE, 0);
1961 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1962 SSP_DMACR_MASK_TXDMAE, 1);
1963 } else {
1964 chip->enable_dma = false;
1965 dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
1966 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1967 SSP_DMACR_MASK_RXDMAE, 0);
1968 SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1969 SSP_DMACR_MASK_TXDMAE, 1);
1972 chip->cpsr = clk_freq.cpsdvsr;
1974 /* Special setup for the ST micro extended control registers */
1975 if (pl022->vendor->extended_cr) {
1976 u32 etx;
1978 if (pl022->vendor->pl023) {
1979 /* These bits are only in the PL023 */
1980 SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
1981 SSP_CR1_MASK_FBCLKDEL_ST, 13);
1982 } else {
1983 /* These bits are in the PL022 but not PL023 */
1984 SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
1985 SSP_CR0_MASK_HALFDUP_ST, 5);
1986 SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
1987 SSP_CR0_MASK_CSS_ST, 16);
1988 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1989 SSP_CR0_MASK_FRF_ST, 21);
1990 SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
1991 SSP_CR1_MASK_MWAIT_ST, 6);
1993 SSP_WRITE_BITS(chip->cr0, bits - 1,
1994 SSP_CR0_MASK_DSS_ST, 0);
1996 if (spi->mode & SPI_LSB_FIRST) {
1997 tmp = SSP_RX_LSB;
1998 etx = SSP_TX_LSB;
1999 } else {
2000 tmp = SSP_RX_MSB;
2001 etx = SSP_TX_MSB;
2003 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
2004 SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
2005 SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
2006 SSP_CR1_MASK_RXIFLSEL_ST, 7);
2007 SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
2008 SSP_CR1_MASK_TXIFLSEL_ST, 10);
2009 } else {
2010 SSP_WRITE_BITS(chip->cr0, bits - 1,
2011 SSP_CR0_MASK_DSS, 0);
2012 SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2013 SSP_CR0_MASK_FRF, 4);
2016 /* Stuff that is common for all versions */
2017 if (spi->mode & SPI_CPOL)
2018 tmp = SSP_CLK_POL_IDLE_HIGH;
2019 else
2020 tmp = SSP_CLK_POL_IDLE_LOW;
2021 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
2023 if (spi->mode & SPI_CPHA)
2024 tmp = SSP_CLK_SECOND_EDGE;
2025 else
2026 tmp = SSP_CLK_FIRST_EDGE;
2027 SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
2029 SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
2030 /* Loopback is available on all versions except PL023 */
2031 if (pl022->vendor->loopback) {
2032 if (spi->mode & SPI_LOOP)
2033 tmp = LOOPBACK_ENABLED;
2034 else
2035 tmp = LOOPBACK_DISABLED;
2036 SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
2038 SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
2039 SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
2040 SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
2043 /* Save controller_state */
2044 spi_set_ctldata(spi, chip);
2045 return status;
2046 err_config_params:
2047 spi_set_ctldata(spi, NULL);
2048 kfree(chip);
2049 return status;
2053 * pl022_cleanup - cleanup function registered to SPI master framework
2054 * @spi: spi device which is requesting cleanup
2056 * This function is registered to the SPI framework for this SPI master
2057 * controller. It will free the runtime state of chip.
2059 static void pl022_cleanup(struct spi_device *spi)
2061 struct chip_data *chip = spi_get_ctldata(spi);
2063 spi_set_ctldata(spi, NULL);
2064 kfree(chip);
2067 static struct pl022_ssp_controller *
2068 pl022_platform_data_dt_get(struct device *dev)
2070 struct device_node *np = dev->of_node;
2071 struct pl022_ssp_controller *pd;
2072 u32 tmp;
2074 if (!np) {
2075 dev_err(dev, "no dt node defined\n");
2076 return NULL;
2079 pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL);
2080 if (!pd)
2081 return NULL;
2083 pd->bus_id = -1;
2084 pd->enable_dma = 1;
2085 of_property_read_u32(np, "num-cs", &tmp);
2086 pd->num_chipselect = tmp;
2087 of_property_read_u32(np, "pl022,autosuspend-delay",
2088 &pd->autosuspend_delay);
2089 pd->rt = of_property_read_bool(np, "pl022,rt");
2091 return pd;
2094 static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
2096 struct device *dev = &adev->dev;
2097 struct pl022_ssp_controller *platform_info =
2098 dev_get_platdata(&adev->dev);
2099 struct spi_master *master;
2100 struct pl022 *pl022 = NULL; /*Data for this driver */
2101 struct device_node *np = adev->dev.of_node;
2102 int status = 0, i, num_cs;
2104 dev_info(&adev->dev,
2105 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
2106 if (!platform_info && IS_ENABLED(CONFIG_OF))
2107 platform_info = pl022_platform_data_dt_get(dev);
2109 if (!platform_info) {
2110 dev_err(dev, "probe: no platform data defined\n");
2111 return -ENODEV;
2114 if (platform_info->num_chipselect) {
2115 num_cs = platform_info->num_chipselect;
2116 } else {
2117 dev_err(dev, "probe: no chip select defined\n");
2118 return -ENODEV;
2121 /* Allocate master with space for data */
2122 master = spi_alloc_master(dev, sizeof(struct pl022));
2123 if (master == NULL) {
2124 dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
2125 return -ENOMEM;
2128 pl022 = spi_master_get_devdata(master);
2129 pl022->master = master;
2130 pl022->master_info = platform_info;
2131 pl022->adev = adev;
2132 pl022->vendor = id->data;
2133 pl022->chipselects = devm_kzalloc(dev, num_cs * sizeof(int),
2134 GFP_KERNEL);
2135 if (!pl022->chipselects) {
2136 status = -ENOMEM;
2137 goto err_no_mem;
2141 * Bus Number Which has been Assigned to this SSP controller
2142 * on this board
2144 master->bus_num = platform_info->bus_id;
2145 master->num_chipselect = num_cs;
2146 master->cleanup = pl022_cleanup;
2147 master->setup = pl022_setup;
2148 master->auto_runtime_pm = true;
2149 master->transfer_one_message = pl022_transfer_one_message;
2150 master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
2151 master->rt = platform_info->rt;
2152 master->dev.of_node = dev->of_node;
2154 if (platform_info->num_chipselect && platform_info->chipselects) {
2155 for (i = 0; i < num_cs; i++)
2156 pl022->chipselects[i] = platform_info->chipselects[i];
2157 } else if (pl022->vendor->internal_cs_ctrl) {
2158 for (i = 0; i < num_cs; i++)
2159 pl022->chipselects[i] = i;
2160 } else if (IS_ENABLED(CONFIG_OF)) {
2161 for (i = 0; i < num_cs; i++) {
2162 int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
2164 if (cs_gpio == -EPROBE_DEFER) {
2165 status = -EPROBE_DEFER;
2166 goto err_no_gpio;
2169 pl022->chipselects[i] = cs_gpio;
2171 if (gpio_is_valid(cs_gpio)) {
2172 if (devm_gpio_request(dev, cs_gpio, "ssp-pl022"))
2173 dev_err(&adev->dev,
2174 "could not request %d gpio\n",
2175 cs_gpio);
2176 else if (gpio_direction_output(cs_gpio, 1))
2177 dev_err(&adev->dev,
2178 "could not set gpio %d as output\n",
2179 cs_gpio);
2185 * Supports mode 0-3, loopback, and active low CS. Transfers are
2186 * always MS bit first on the original pl022.
2188 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
2189 if (pl022->vendor->extended_cr)
2190 master->mode_bits |= SPI_LSB_FIRST;
2192 dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
2194 status = amba_request_regions(adev, NULL);
2195 if (status)
2196 goto err_no_ioregion;
2198 pl022->phybase = adev->res.start;
2199 pl022->virtbase = devm_ioremap(dev, adev->res.start,
2200 resource_size(&adev->res));
2201 if (pl022->virtbase == NULL) {
2202 status = -ENOMEM;
2203 goto err_no_ioremap;
2205 dev_info(&adev->dev, "mapped registers from %pa to %p\n",
2206 &adev->res.start, pl022->virtbase);
2208 pl022->clk = devm_clk_get(&adev->dev, NULL);
2209 if (IS_ERR(pl022->clk)) {
2210 status = PTR_ERR(pl022->clk);
2211 dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
2212 goto err_no_clk;
2215 status = clk_prepare_enable(pl022->clk);
2216 if (status) {
2217 dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
2218 goto err_no_clk_en;
2221 /* Initialize transfer pump */
2222 tasklet_init(&pl022->pump_transfers, pump_transfers,
2223 (unsigned long)pl022);
2225 /* Disable SSP */
2226 writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
2227 SSP_CR1(pl022->virtbase));
2228 load_ssp_default_config(pl022);
2230 status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler,
2231 0, "pl022", pl022);
2232 if (status < 0) {
2233 dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
2234 goto err_no_irq;
2237 /* Get DMA channels, try autoconfiguration first */
2238 status = pl022_dma_autoprobe(pl022);
2240 /* If that failed, use channels from platform_info */
2241 if (status == 0)
2242 platform_info->enable_dma = 1;
2243 else if (platform_info->enable_dma) {
2244 status = pl022_dma_probe(pl022);
2245 if (status != 0)
2246 platform_info->enable_dma = 0;
2249 /* Register with the SPI framework */
2250 amba_set_drvdata(adev, pl022);
2251 status = devm_spi_register_master(&adev->dev, master);
2252 if (status != 0) {
2253 dev_err(&adev->dev,
2254 "probe - problem registering spi master\n");
2255 goto err_spi_register;
2257 dev_dbg(dev, "probe succeeded\n");
2259 /* let runtime pm put suspend */
2260 if (platform_info->autosuspend_delay > 0) {
2261 dev_info(&adev->dev,
2262 "will use autosuspend for runtime pm, delay %dms\n",
2263 platform_info->autosuspend_delay);
2264 pm_runtime_set_autosuspend_delay(dev,
2265 platform_info->autosuspend_delay);
2266 pm_runtime_use_autosuspend(dev);
2268 pm_runtime_put(dev);
2270 return 0;
2272 err_spi_register:
2273 if (platform_info->enable_dma)
2274 pl022_dma_remove(pl022);
2275 err_no_irq:
2276 clk_disable_unprepare(pl022->clk);
2277 err_no_clk_en:
2278 err_no_clk:
2279 err_no_ioremap:
2280 amba_release_regions(adev);
2281 err_no_ioregion:
2282 err_no_gpio:
2283 err_no_mem:
2284 spi_master_put(master);
2285 return status;
2288 static int
2289 pl022_remove(struct amba_device *adev)
2291 struct pl022 *pl022 = amba_get_drvdata(adev);
2293 if (!pl022)
2294 return 0;
2297 * undo pm_runtime_put() in probe. I assume that we're not
2298 * accessing the primecell here.
2300 pm_runtime_get_noresume(&adev->dev);
2302 load_ssp_default_config(pl022);
2303 if (pl022->master_info->enable_dma)
2304 pl022_dma_remove(pl022);
2306 clk_disable_unprepare(pl022->clk);
2307 amba_release_regions(adev);
2308 tasklet_disable(&pl022->pump_transfers);
2309 return 0;
2312 #ifdef CONFIG_PM_SLEEP
2313 static int pl022_suspend(struct device *dev)
2315 struct pl022 *pl022 = dev_get_drvdata(dev);
2316 int ret;
2318 ret = spi_master_suspend(pl022->master);
2319 if (ret) {
2320 dev_warn(dev, "cannot suspend master\n");
2321 return ret;
2324 ret = pm_runtime_force_suspend(dev);
2325 if (ret) {
2326 spi_master_resume(pl022->master);
2327 return ret;
2330 pinctrl_pm_select_sleep_state(dev);
2332 dev_dbg(dev, "suspended\n");
2333 return 0;
2336 static int pl022_resume(struct device *dev)
2338 struct pl022 *pl022 = dev_get_drvdata(dev);
2339 int ret;
2341 ret = pm_runtime_force_resume(dev);
2342 if (ret)
2343 dev_err(dev, "problem resuming\n");
2345 /* Start the queue running */
2346 ret = spi_master_resume(pl022->master);
2347 if (ret)
2348 dev_err(dev, "problem starting queue (%d)\n", ret);
2349 else
2350 dev_dbg(dev, "resumed\n");
2352 return ret;
2354 #endif
2356 #ifdef CONFIG_PM
2357 static int pl022_runtime_suspend(struct device *dev)
2359 struct pl022 *pl022 = dev_get_drvdata(dev);
2361 clk_disable_unprepare(pl022->clk);
2362 pinctrl_pm_select_idle_state(dev);
2364 return 0;
2367 static int pl022_runtime_resume(struct device *dev)
2369 struct pl022 *pl022 = dev_get_drvdata(dev);
2371 pinctrl_pm_select_default_state(dev);
2372 clk_prepare_enable(pl022->clk);
2374 return 0;
2376 #endif
2378 static const struct dev_pm_ops pl022_dev_pm_ops = {
2379 SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2380 SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2383 static struct vendor_data vendor_arm = {
2384 .fifodepth = 8,
2385 .max_bpw = 16,
2386 .unidir = false,
2387 .extended_cr = false,
2388 .pl023 = false,
2389 .loopback = true,
2390 .internal_cs_ctrl = false,
2393 static struct vendor_data vendor_st = {
2394 .fifodepth = 32,
2395 .max_bpw = 32,
2396 .unidir = false,
2397 .extended_cr = true,
2398 .pl023 = false,
2399 .loopback = true,
2400 .internal_cs_ctrl = false,
2403 static struct vendor_data vendor_st_pl023 = {
2404 .fifodepth = 32,
2405 .max_bpw = 32,
2406 .unidir = false,
2407 .extended_cr = true,
2408 .pl023 = true,
2409 .loopback = false,
2410 .internal_cs_ctrl = false,
2413 static struct vendor_data vendor_lsi = {
2414 .fifodepth = 8,
2415 .max_bpw = 16,
2416 .unidir = false,
2417 .extended_cr = false,
2418 .pl023 = false,
2419 .loopback = true,
2420 .internal_cs_ctrl = true,
2423 static struct amba_id pl022_ids[] = {
2426 * ARM PL022 variant, this has a 16bit wide
2427 * and 8 locations deep TX/RX FIFO
2429 .id = 0x00041022,
2430 .mask = 0x000fffff,
2431 .data = &vendor_arm,
2435 * ST Micro derivative, this has 32bit wide
2436 * and 32 locations deep TX/RX FIFO
2438 .id = 0x01080022,
2439 .mask = 0xffffffff,
2440 .data = &vendor_st,
2444 * ST-Ericsson derivative "PL023" (this is not
2445 * an official ARM number), this is a PL022 SSP block
2446 * stripped to SPI mode only, it has 32bit wide
2447 * and 32 locations deep TX/RX FIFO but no extended
2448 * CR0/CR1 register
2450 .id = 0x00080023,
2451 .mask = 0xffffffff,
2452 .data = &vendor_st_pl023,
2456 * PL022 variant that has a chip select control register whih
2457 * allows control of 5 output signals nCS[0:4].
2459 .id = 0x000b6022,
2460 .mask = 0x000fffff,
2461 .data = &vendor_lsi,
2463 { 0, 0 },
2466 MODULE_DEVICE_TABLE(amba, pl022_ids);
2468 static struct amba_driver pl022_driver = {
2469 .drv = {
2470 .name = "ssp-pl022",
2471 .pm = &pl022_dev_pm_ops,
2473 .id_table = pl022_ids,
2474 .probe = pl022_probe,
2475 .remove = pl022_remove,
2478 static int __init pl022_init(void)
2480 return amba_driver_register(&pl022_driver);
2482 subsys_initcall(pl022_init);
2484 static void __exit pl022_exit(void)
2486 amba_driver_unregister(&pl022_driver);
2488 module_exit(pl022_exit);
2490 MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2491 MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2492 MODULE_LICENSE("GPL");