Linux-libre 5.4.49-gnu
[librecmc/linux-libre.git] / drivers / spi / spi-orion.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Marvell Orion SPI controller driver
4  *
5  * Author: Shadi Ammouri <shadi@marvell.com>
6  * Copyright (C) 2007-2008 Marvell Ltd.
7  */
8
9 #include <linux/interrupt.h>
10 #include <linux/delay.h>
11 #include <linux/platform_device.h>
12 #include <linux/err.h>
13 #include <linux/io.h>
14 #include <linux/spi/spi.h>
15 #include <linux/module.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/of.h>
18 #include <linux/of_address.h>
19 #include <linux/of_device.h>
20 #include <linux/of_gpio.h>
21 #include <linux/clk.h>
22 #include <linux/sizes.h>
23 #include <linux/gpio.h>
24 #include <asm/unaligned.h>
25
26 #define DRIVER_NAME                     "orion_spi"
27
28 /* Runtime PM autosuspend timeout: PM is fairly light on this driver */
29 #define SPI_AUTOSUSPEND_TIMEOUT         200
30
31 /* Some SoCs using this driver support up to 8 chip selects.
32  * It is up to the implementer to only use the chip selects
33  * that are available.
34  */
35 #define ORION_NUM_CHIPSELECTS           8
36
37 #define ORION_SPI_WAIT_RDY_MAX_LOOP     2000 /* in usec */
38
39 #define ORION_SPI_IF_CTRL_REG           0x00
40 #define ORION_SPI_IF_CONFIG_REG         0x04
41 #define ORION_SPI_IF_RXLSBF             BIT(14)
42 #define ORION_SPI_IF_TXLSBF             BIT(13)
43 #define ORION_SPI_DATA_OUT_REG          0x08
44 #define ORION_SPI_DATA_IN_REG           0x0c
45 #define ORION_SPI_INT_CAUSE_REG         0x10
46 #define ORION_SPI_TIMING_PARAMS_REG     0x18
47
48 /* Register for the "Direct Mode" */
49 #define SPI_DIRECT_WRITE_CONFIG_REG     0x20
50
51 #define ORION_SPI_TMISO_SAMPLE_MASK     (0x3 << 6)
52 #define ORION_SPI_TMISO_SAMPLE_1        (1 << 6)
53 #define ORION_SPI_TMISO_SAMPLE_2        (2 << 6)
54
55 #define ORION_SPI_MODE_CPOL             (1 << 11)
56 #define ORION_SPI_MODE_CPHA             (1 << 12)
57 #define ORION_SPI_IF_8_16_BIT_MODE      (1 << 5)
58 #define ORION_SPI_CLK_PRESCALE_MASK     0x1F
59 #define ARMADA_SPI_CLK_PRESCALE_MASK    0xDF
60 #define ORION_SPI_MODE_MASK             (ORION_SPI_MODE_CPOL | \
61                                          ORION_SPI_MODE_CPHA)
62 #define ORION_SPI_CS_MASK       0x1C
63 #define ORION_SPI_CS_SHIFT      2
64 #define ORION_SPI_CS(cs)        ((cs << ORION_SPI_CS_SHIFT) & \
65                                         ORION_SPI_CS_MASK)
66
67 enum orion_spi_type {
68         ORION_SPI,
69         ARMADA_SPI,
70 };
71
72 struct orion_spi_dev {
73         enum orion_spi_type     typ;
74         /*
75          * min_divisor and max_hz should be exclusive, the only we can
76          * have both is for managing the armada-370-spi case with old
77          * device tree
78          */
79         unsigned long           max_hz;
80         unsigned int            min_divisor;
81         unsigned int            max_divisor;
82         u32                     prescale_mask;
83         bool                    is_errata_50mhz_ac;
84 };
85
86 struct orion_direct_acc {
87         void __iomem            *vaddr;
88         u32                     size;
89 };
90
91 struct orion_child_options {
92         struct orion_direct_acc direct_access;
93 };
94
95 struct orion_spi {
96         struct spi_master       *master;
97         void __iomem            *base;
98         struct clk              *clk;
99         struct clk              *axi_clk;
100         const struct orion_spi_dev *devdata;
101         int                     unused_hw_gpio;
102
103         struct orion_child_options      child[ORION_NUM_CHIPSELECTS];
104 };
105
106 static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg)
107 {
108         return orion_spi->base + reg;
109 }
110
111 static inline void
112 orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
113 {
114         void __iomem *reg_addr = spi_reg(orion_spi, reg);
115         u32 val;
116
117         val = readl(reg_addr);
118         val |= mask;
119         writel(val, reg_addr);
120 }
121
122 static inline void
123 orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
124 {
125         void __iomem *reg_addr = spi_reg(orion_spi, reg);
126         u32 val;
127
128         val = readl(reg_addr);
129         val &= ~mask;
130         writel(val, reg_addr);
131 }
132
133 static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed)
134 {
135         u32 tclk_hz;
136         u32 rate;
137         u32 prescale;
138         u32 reg;
139         struct orion_spi *orion_spi;
140         const struct orion_spi_dev *devdata;
141
142         orion_spi = spi_master_get_devdata(spi->master);
143         devdata = orion_spi->devdata;
144
145         tclk_hz = clk_get_rate(orion_spi->clk);
146
147         if (devdata->typ == ARMADA_SPI) {
148                 /*
149                  * Given the core_clk (tclk_hz) and the target rate (speed) we
150                  * determine the best values for SPR (in [0 .. 15]) and SPPR (in
151                  * [0..7]) such that
152                  *
153                  *      core_clk / (SPR * 2 ** SPPR)
154                  *
155                  * is as big as possible but not bigger than speed.
156                  */
157
158                 /* best integer divider: */
159                 unsigned divider = DIV_ROUND_UP(tclk_hz, speed);
160                 unsigned spr, sppr;
161
162                 if (divider < 16) {
163                         /* This is the easy case, divider is less than 16 */
164                         spr = divider;
165                         sppr = 0;
166
167                 } else {
168                         unsigned two_pow_sppr;
169                         /*
170                          * Find the highest bit set in divider. This and the
171                          * three next bits define SPR (apart from rounding).
172                          * SPPR is then the number of zero bits that must be
173                          * appended:
174                          */
175                         sppr = fls(divider) - 4;
176
177                         /*
178                          * As SPR only has 4 bits, we have to round divider up
179                          * to the next multiple of 2 ** sppr.
180                          */
181                         two_pow_sppr = 1 << sppr;
182                         divider = (divider + two_pow_sppr - 1) & -two_pow_sppr;
183
184                         /*
185                          * recalculate sppr as rounding up divider might have
186                          * increased it enough to change the position of the
187                          * highest set bit. In this case the bit that now
188                          * doesn't make it into SPR is 0, so there is no need to
189                          * round again.
190                          */
191                         sppr = fls(divider) - 4;
192                         spr = divider >> sppr;
193
194                         /*
195                          * Now do range checking. SPR is constructed to have a
196                          * width of 4 bits, so this is fine for sure. So we
197                          * still need to check for sppr to fit into 3 bits:
198                          */
199                         if (sppr > 7)
200                                 return -EINVAL;
201                 }
202
203                 prescale = ((sppr & 0x6) << 5) | ((sppr & 0x1) << 4) | spr;
204         } else {
205                 /*
206                  * the supported rates are: 4,6,8...30
207                  * round up as we look for equal or less speed
208                  */
209                 rate = DIV_ROUND_UP(tclk_hz, speed);
210                 rate = roundup(rate, 2);
211
212                 /* check if requested speed is too small */
213                 if (rate > 30)
214                         return -EINVAL;
215
216                 if (rate < 4)
217                         rate = 4;
218
219                 /* Convert the rate to SPI clock divisor value. */
220                 prescale = 0x10 + rate/2;
221         }
222
223         reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
224         reg = ((reg & ~devdata->prescale_mask) | prescale);
225         writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
226
227         return 0;
228 }
229
230 static void
231 orion_spi_mode_set(struct spi_device *spi)
232 {
233         u32 reg;
234         struct orion_spi *orion_spi;
235
236         orion_spi = spi_master_get_devdata(spi->master);
237
238         reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
239         reg &= ~ORION_SPI_MODE_MASK;
240         if (spi->mode & SPI_CPOL)
241                 reg |= ORION_SPI_MODE_CPOL;
242         if (spi->mode & SPI_CPHA)
243                 reg |= ORION_SPI_MODE_CPHA;
244         if (spi->mode & SPI_LSB_FIRST)
245                 reg |= ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF;
246         else
247                 reg &= ~(ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF);
248
249         writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
250 }
251
252 static void
253 orion_spi_50mhz_ac_timing_erratum(struct spi_device *spi, unsigned int speed)
254 {
255         u32 reg;
256         struct orion_spi *orion_spi;
257
258         orion_spi = spi_master_get_devdata(spi->master);
259
260         /*
261          * Erratum description: (Erratum NO. FE-9144572) The device
262          * SPI interface supports frequencies of up to 50 MHz.
263          * However, due to this erratum, when the device core clock is
264          * 250 MHz and the SPI interfaces is configured for 50MHz SPI
265          * clock and CPOL=CPHA=1 there might occur data corruption on
266          * reads from the SPI device.
267          * Erratum Workaround:
268          * Work in one of the following configurations:
269          * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
270          * Register".
271          * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
272          * Register" before setting the interface.
273          */
274         reg = readl(spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
275         reg &= ~ORION_SPI_TMISO_SAMPLE_MASK;
276
277         if (clk_get_rate(orion_spi->clk) == 250000000 &&
278                         speed == 50000000 && spi->mode & SPI_CPOL &&
279                         spi->mode & SPI_CPHA)
280                 reg |= ORION_SPI_TMISO_SAMPLE_2;
281         else
282                 reg |= ORION_SPI_TMISO_SAMPLE_1; /* This is the default value */
283
284         writel(reg, spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
285 }
286
287 /*
288  * called only when no transfer is active on the bus
289  */
290 static int
291 orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
292 {
293         struct orion_spi *orion_spi;
294         unsigned int speed = spi->max_speed_hz;
295         unsigned int bits_per_word = spi->bits_per_word;
296         int     rc;
297
298         orion_spi = spi_master_get_devdata(spi->master);
299
300         if ((t != NULL) && t->speed_hz)
301                 speed = t->speed_hz;
302
303         if ((t != NULL) && t->bits_per_word)
304                 bits_per_word = t->bits_per_word;
305
306         orion_spi_mode_set(spi);
307
308         if (orion_spi->devdata->is_errata_50mhz_ac)
309                 orion_spi_50mhz_ac_timing_erratum(spi, speed);
310
311         rc = orion_spi_baudrate_set(spi, speed);
312         if (rc)
313                 return rc;
314
315         if (bits_per_word == 16)
316                 orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
317                                   ORION_SPI_IF_8_16_BIT_MODE);
318         else
319                 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
320                                   ORION_SPI_IF_8_16_BIT_MODE);
321
322         return 0;
323 }
324
325 static void orion_spi_set_cs(struct spi_device *spi, bool enable)
326 {
327         struct orion_spi *orion_spi;
328         int cs;
329
330         orion_spi = spi_master_get_devdata(spi->master);
331
332         if (gpio_is_valid(spi->cs_gpio))
333                 cs = orion_spi->unused_hw_gpio;
334         else
335                 cs = spi->chip_select;
336
337         orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, ORION_SPI_CS_MASK);
338         orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG,
339                                 ORION_SPI_CS(cs));
340
341         /* Chip select logic is inverted from spi_set_cs */
342         if (!enable)
343                 orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
344         else
345                 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
346 }
347
348 static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi)
349 {
350         int i;
351
352         for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) {
353                 if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG)))
354                         return 1;
355
356                 udelay(1);
357         }
358
359         return -1;
360 }
361
362 static inline int
363 orion_spi_write_read_8bit(struct spi_device *spi,
364                           const u8 **tx_buf, u8 **rx_buf)
365 {
366         void __iomem *tx_reg, *rx_reg, *int_reg;
367         struct orion_spi *orion_spi;
368
369         orion_spi = spi_master_get_devdata(spi->master);
370         tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
371         rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
372         int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
373
374         /* clear the interrupt cause register */
375         writel(0x0, int_reg);
376
377         if (tx_buf && *tx_buf)
378                 writel(*(*tx_buf)++, tx_reg);
379         else
380                 writel(0, tx_reg);
381
382         if (orion_spi_wait_till_ready(orion_spi) < 0) {
383                 dev_err(&spi->dev, "TXS timed out\n");
384                 return -1;
385         }
386
387         if (rx_buf && *rx_buf)
388                 *(*rx_buf)++ = readl(rx_reg);
389
390         return 1;
391 }
392
393 static inline int
394 orion_spi_write_read_16bit(struct spi_device *spi,
395                            const u16 **tx_buf, u16 **rx_buf)
396 {
397         void __iomem *tx_reg, *rx_reg, *int_reg;
398         struct orion_spi *orion_spi;
399
400         orion_spi = spi_master_get_devdata(spi->master);
401         tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
402         rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
403         int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
404
405         /* clear the interrupt cause register */
406         writel(0x0, int_reg);
407
408         if (tx_buf && *tx_buf)
409                 writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg);
410         else
411                 writel(0, tx_reg);
412
413         if (orion_spi_wait_till_ready(orion_spi) < 0) {
414                 dev_err(&spi->dev, "TXS timed out\n");
415                 return -1;
416         }
417
418         if (rx_buf && *rx_buf)
419                 put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++);
420
421         return 1;
422 }
423
424 static unsigned int
425 orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer)
426 {
427         unsigned int count;
428         int word_len;
429         struct orion_spi *orion_spi;
430         int cs = spi->chip_select;
431         void __iomem *vaddr;
432
433         word_len = spi->bits_per_word;
434         count = xfer->len;
435
436         orion_spi = spi_master_get_devdata(spi->master);
437
438         /*
439          * Use SPI direct write mode if base address is available. Otherwise
440          * fall back to PIO mode for this transfer.
441          */
442         vaddr = orion_spi->child[cs].direct_access.vaddr;
443
444         if (vaddr && xfer->tx_buf && word_len == 8) {
445                 unsigned int cnt = count / 4;
446                 unsigned int rem = count % 4;
447
448                 /*
449                  * Send the TX-data to the SPI device via the direct
450                  * mapped address window
451                  */
452                 iowrite32_rep(vaddr, xfer->tx_buf, cnt);
453                 if (rem) {
454                         u32 *buf = (u32 *)xfer->tx_buf;
455
456                         iowrite8_rep(vaddr, &buf[cnt], rem);
457                 }
458
459                 return count;
460         }
461
462         if (word_len == 8) {
463                 const u8 *tx = xfer->tx_buf;
464                 u8 *rx = xfer->rx_buf;
465
466                 do {
467                         if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0)
468                                 goto out;
469                         count--;
470                         if (xfer->word_delay_usecs)
471                                 udelay(xfer->word_delay_usecs);
472                 } while (count);
473         } else if (word_len == 16) {
474                 const u16 *tx = xfer->tx_buf;
475                 u16 *rx = xfer->rx_buf;
476
477                 do {
478                         if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0)
479                                 goto out;
480                         count -= 2;
481                         if (xfer->word_delay_usecs)
482                                 udelay(xfer->word_delay_usecs);
483                 } while (count);
484         }
485
486 out:
487         return xfer->len - count;
488 }
489
490 static int orion_spi_transfer_one(struct spi_master *master,
491                                         struct spi_device *spi,
492                                         struct spi_transfer *t)
493 {
494         int status = 0;
495
496         status = orion_spi_setup_transfer(spi, t);
497         if (status < 0)
498                 return status;
499
500         if (t->len)
501                 orion_spi_write_read(spi, t);
502
503         return status;
504 }
505
506 static int orion_spi_setup(struct spi_device *spi)
507 {
508         if (gpio_is_valid(spi->cs_gpio)) {
509                 gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
510         }
511         return orion_spi_setup_transfer(spi, NULL);
512 }
513
514 static int orion_spi_reset(struct orion_spi *orion_spi)
515 {
516         /* Verify that the CS is deasserted */
517         orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
518
519         /* Don't deassert CS between the direct mapped SPI transfers */
520         writel(0, spi_reg(orion_spi, SPI_DIRECT_WRITE_CONFIG_REG));
521
522         return 0;
523 }
524
525 static const struct orion_spi_dev orion_spi_dev_data = {
526         .typ = ORION_SPI,
527         .min_divisor = 4,
528         .max_divisor = 30,
529         .prescale_mask = ORION_SPI_CLK_PRESCALE_MASK,
530 };
531
532 static const struct orion_spi_dev armada_370_spi_dev_data = {
533         .typ = ARMADA_SPI,
534         .min_divisor = 4,
535         .max_divisor = 1920,
536         .max_hz = 50000000,
537         .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
538 };
539
540 static const struct orion_spi_dev armada_xp_spi_dev_data = {
541         .typ = ARMADA_SPI,
542         .max_hz = 50000000,
543         .max_divisor = 1920,
544         .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
545 };
546
547 static const struct orion_spi_dev armada_375_spi_dev_data = {
548         .typ = ARMADA_SPI,
549         .min_divisor = 15,
550         .max_divisor = 1920,
551         .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
552 };
553
554 static const struct orion_spi_dev armada_380_spi_dev_data = {
555         .typ = ARMADA_SPI,
556         .max_hz = 50000000,
557         .max_divisor = 1920,
558         .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
559         .is_errata_50mhz_ac = true,
560 };
561
562 static const struct of_device_id orion_spi_of_match_table[] = {
563         {
564                 .compatible = "marvell,orion-spi",
565                 .data = &orion_spi_dev_data,
566         },
567         {
568                 .compatible = "marvell,armada-370-spi",
569                 .data = &armada_370_spi_dev_data,
570         },
571         {
572                 .compatible = "marvell,armada-375-spi",
573                 .data = &armada_375_spi_dev_data,
574         },
575         {
576                 .compatible = "marvell,armada-380-spi",
577                 .data = &armada_380_spi_dev_data,
578         },
579         {
580                 .compatible = "marvell,armada-390-spi",
581                 .data = &armada_xp_spi_dev_data,
582         },
583         {
584                 .compatible = "marvell,armada-xp-spi",
585                 .data = &armada_xp_spi_dev_data,
586         },
587
588         {}
589 };
590 MODULE_DEVICE_TABLE(of, orion_spi_of_match_table);
591
592 static int orion_spi_probe(struct platform_device *pdev)
593 {
594         const struct of_device_id *of_id;
595         const struct orion_spi_dev *devdata;
596         struct spi_master *master;
597         struct orion_spi *spi;
598         struct resource *r;
599         unsigned long tclk_hz;
600         int status = 0;
601         struct device_node *np;
602
603         master = spi_alloc_master(&pdev->dev, sizeof(*spi));
604         if (master == NULL) {
605                 dev_dbg(&pdev->dev, "master allocation failed\n");
606                 return -ENOMEM;
607         }
608
609         if (pdev->id != -1)
610                 master->bus_num = pdev->id;
611         if (pdev->dev.of_node) {
612                 u32 cell_index;
613
614                 if (!of_property_read_u32(pdev->dev.of_node, "cell-index",
615                                           &cell_index))
616                         master->bus_num = cell_index;
617         }
618
619         /* we support all 4 SPI modes and LSB first option */
620         master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST;
621         master->set_cs = orion_spi_set_cs;
622         master->transfer_one = orion_spi_transfer_one;
623         master->num_chipselect = ORION_NUM_CHIPSELECTS;
624         master->setup = orion_spi_setup;
625         master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
626         master->auto_runtime_pm = true;
627         master->flags = SPI_MASTER_GPIO_SS;
628
629         platform_set_drvdata(pdev, master);
630
631         spi = spi_master_get_devdata(master);
632         spi->master = master;
633         spi->unused_hw_gpio = -1;
634
635         of_id = of_match_device(orion_spi_of_match_table, &pdev->dev);
636         devdata = (of_id) ? of_id->data : &orion_spi_dev_data;
637         spi->devdata = devdata;
638
639         spi->clk = devm_clk_get(&pdev->dev, NULL);
640         if (IS_ERR(spi->clk)) {
641                 status = PTR_ERR(spi->clk);
642                 goto out;
643         }
644
645         status = clk_prepare_enable(spi->clk);
646         if (status)
647                 goto out;
648
649         /* The following clock is only used by some SoCs */
650         spi->axi_clk = devm_clk_get(&pdev->dev, "axi");
651         if (IS_ERR(spi->axi_clk) &&
652             PTR_ERR(spi->axi_clk) == -EPROBE_DEFER) {
653                 status = -EPROBE_DEFER;
654                 goto out_rel_clk;
655         }
656         if (!IS_ERR(spi->axi_clk))
657                 clk_prepare_enable(spi->axi_clk);
658
659         tclk_hz = clk_get_rate(spi->clk);
660
661         /*
662          * With old device tree, armada-370-spi could be used with
663          * Armada XP, however for this SoC the maximum frequency is
664          * 50MHz instead of tclk/4. On Armada 370, tclk cannot be
665          * higher than 200MHz. So, in order to be able to handle both
666          * SoCs, we can take the minimum of 50MHz and tclk/4.
667          */
668         if (of_device_is_compatible(pdev->dev.of_node,
669                                         "marvell,armada-370-spi"))
670                 master->max_speed_hz = min(devdata->max_hz,
671                                 DIV_ROUND_UP(tclk_hz, devdata->min_divisor));
672         else if (devdata->min_divisor)
673                 master->max_speed_hz =
674                         DIV_ROUND_UP(tclk_hz, devdata->min_divisor);
675         else
676                 master->max_speed_hz = devdata->max_hz;
677         master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor);
678
679         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
680         spi->base = devm_ioremap_resource(&pdev->dev, r);
681         if (IS_ERR(spi->base)) {
682                 status = PTR_ERR(spi->base);
683                 goto out_rel_axi_clk;
684         }
685
686         for_each_available_child_of_node(pdev->dev.of_node, np) {
687                 struct orion_direct_acc *dir_acc;
688                 u32 cs;
689                 int cs_gpio;
690
691                 /* Get chip-select number from the "reg" property */
692                 status = of_property_read_u32(np, "reg", &cs);
693                 if (status) {
694                         dev_err(&pdev->dev,
695                                 "%pOF has no valid 'reg' property (%d)\n",
696                                 np, status);
697                         continue;
698                 }
699
700                 /*
701                  * Initialize the CS GPIO:
702                  * - properly request the actual GPIO signal
703                  * - de-assert the logical signal so that all GPIO CS lines
704                  *   are inactive when probing for slaves
705                  * - find an unused physical CS which will be driven for any
706                  *   slave which uses a CS GPIO
707                  */
708                 cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", cs);
709                 if (cs_gpio > 0) {
710                         char *gpio_name;
711                         int cs_flags;
712
713                         if (spi->unused_hw_gpio == -1) {
714                                 dev_info(&pdev->dev,
715                                         "Selected unused HW CS#%d for any GPIO CSes\n",
716                                         cs);
717                                 spi->unused_hw_gpio = cs;
718                         }
719
720                         gpio_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
721                                         "%s-CS%d", dev_name(&pdev->dev), cs);
722                         if (!gpio_name) {
723                                 status = -ENOMEM;
724                                 goto out_rel_axi_clk;
725                         }
726
727                         cs_flags = of_property_read_bool(np, "spi-cs-high") ?
728                                 GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
729                         status = devm_gpio_request_one(&pdev->dev, cs_gpio,
730                                         cs_flags, gpio_name);
731                         if (status) {
732                                 dev_err(&pdev->dev,
733                                         "Can't request GPIO for CS %d\n", cs);
734                                 goto out_rel_axi_clk;
735                         }
736                 }
737
738                 /*
739                  * Check if an address is configured for this SPI device. If
740                  * not, the MBus mapping via the 'ranges' property in the 'soc'
741                  * node is not configured and this device should not use the
742                  * direct mode. In this case, just continue with the next
743                  * device.
744                  */
745                 status = of_address_to_resource(pdev->dev.of_node, cs + 1, r);
746                 if (status)
747                         continue;
748
749                 /*
750                  * Only map one page for direct access. This is enough for the
751                  * simple TX transfer which only writes to the first word.
752                  * This needs to get extended for the direct SPI-NOR / SPI-NAND
753                  * support, once this gets implemented.
754                  */
755                 dir_acc = &spi->child[cs].direct_access;
756                 dir_acc->vaddr = devm_ioremap(&pdev->dev, r->start, PAGE_SIZE);
757                 if (!dir_acc->vaddr) {
758                         status = -ENOMEM;
759                         goto out_rel_axi_clk;
760                 }
761                 dir_acc->size = PAGE_SIZE;
762
763                 dev_info(&pdev->dev, "CS%d configured for direct access\n", cs);
764         }
765
766         pm_runtime_set_active(&pdev->dev);
767         pm_runtime_use_autosuspend(&pdev->dev);
768         pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
769         pm_runtime_enable(&pdev->dev);
770
771         status = orion_spi_reset(spi);
772         if (status < 0)
773                 goto out_rel_pm;
774
775         pm_runtime_mark_last_busy(&pdev->dev);
776         pm_runtime_put_autosuspend(&pdev->dev);
777
778         master->dev.of_node = pdev->dev.of_node;
779         status = spi_register_master(master);
780         if (status < 0)
781                 goto out_rel_pm;
782
783         return status;
784
785 out_rel_pm:
786         pm_runtime_disable(&pdev->dev);
787 out_rel_axi_clk:
788         clk_disable_unprepare(spi->axi_clk);
789 out_rel_clk:
790         clk_disable_unprepare(spi->clk);
791 out:
792         spi_master_put(master);
793         return status;
794 }
795
796
797 static int orion_spi_remove(struct platform_device *pdev)
798 {
799         struct spi_master *master = platform_get_drvdata(pdev);
800         struct orion_spi *spi = spi_master_get_devdata(master);
801
802         pm_runtime_get_sync(&pdev->dev);
803         clk_disable_unprepare(spi->axi_clk);
804         clk_disable_unprepare(spi->clk);
805
806         spi_unregister_master(master);
807         pm_runtime_disable(&pdev->dev);
808
809         return 0;
810 }
811
812 MODULE_ALIAS("platform:" DRIVER_NAME);
813
814 #ifdef CONFIG_PM
815 static int orion_spi_runtime_suspend(struct device *dev)
816 {
817         struct spi_master *master = dev_get_drvdata(dev);
818         struct orion_spi *spi = spi_master_get_devdata(master);
819
820         clk_disable_unprepare(spi->axi_clk);
821         clk_disable_unprepare(spi->clk);
822         return 0;
823 }
824
825 static int orion_spi_runtime_resume(struct device *dev)
826 {
827         struct spi_master *master = dev_get_drvdata(dev);
828         struct orion_spi *spi = spi_master_get_devdata(master);
829
830         if (!IS_ERR(spi->axi_clk))
831                 clk_prepare_enable(spi->axi_clk);
832         return clk_prepare_enable(spi->clk);
833 }
834 #endif
835
836 static const struct dev_pm_ops orion_spi_pm_ops = {
837         SET_RUNTIME_PM_OPS(orion_spi_runtime_suspend,
838                            orion_spi_runtime_resume,
839                            NULL)
840 };
841
842 static struct platform_driver orion_spi_driver = {
843         .driver = {
844                 .name   = DRIVER_NAME,
845                 .pm     = &orion_spi_pm_ops,
846                 .of_match_table = of_match_ptr(orion_spi_of_match_table),
847         },
848         .probe          = orion_spi_probe,
849         .remove         = orion_spi_remove,
850 };
851
852 module_platform_driver(orion_spi_driver);
853
854 MODULE_DESCRIPTION("Orion SPI driver");
855 MODULE_AUTHOR("Shadi Ammouri <shadi@marvell.com>");
856 MODULE_LICENSE("GPL");