Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
[linux-2.6-microblaze.git] / drivers / spi / spi-sun6i.c
1 /*
2  * Copyright (C) 2012 - 2014 Allwinner Tech
3  * Pan Nan <pannan@allwinnertech.com>
4  *
5  * Copyright (C) 2014 Maxime Ripard
6  * Maxime Ripard <maxime.ripard@free-electrons.com>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  */
13
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/device.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/module.h>
20 #include <linux/of_device.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/reset.h>
24
25 #include <linux/spi/spi.h>
26
27 #define SUN6I_FIFO_DEPTH                128
28 #define SUN8I_FIFO_DEPTH                64
29
30 #define SUN6I_GBL_CTL_REG               0x04
31 #define SUN6I_GBL_CTL_BUS_ENABLE                BIT(0)
32 #define SUN6I_GBL_CTL_MASTER                    BIT(1)
33 #define SUN6I_GBL_CTL_TP                        BIT(7)
34 #define SUN6I_GBL_CTL_RST                       BIT(31)
35
36 #define SUN6I_TFR_CTL_REG               0x08
37 #define SUN6I_TFR_CTL_CPHA                      BIT(0)
38 #define SUN6I_TFR_CTL_CPOL                      BIT(1)
39 #define SUN6I_TFR_CTL_SPOL                      BIT(2)
40 #define SUN6I_TFR_CTL_CS_MASK                   0x30
41 #define SUN6I_TFR_CTL_CS(cs)                    (((cs) << 4) & SUN6I_TFR_CTL_CS_MASK)
42 #define SUN6I_TFR_CTL_CS_MANUAL                 BIT(6)
43 #define SUN6I_TFR_CTL_CS_LEVEL                  BIT(7)
44 #define SUN6I_TFR_CTL_DHB                       BIT(8)
45 #define SUN6I_TFR_CTL_FBS                       BIT(12)
46 #define SUN6I_TFR_CTL_XCH                       BIT(31)
47
48 #define SUN6I_INT_CTL_REG               0x10
49 #define SUN6I_INT_CTL_RF_RDY                    BIT(0)
50 #define SUN6I_INT_CTL_TF_ERQ                    BIT(4)
51 #define SUN6I_INT_CTL_RF_OVF                    BIT(8)
52 #define SUN6I_INT_CTL_TC                        BIT(12)
53
54 #define SUN6I_INT_STA_REG               0x14
55
56 #define SUN6I_FIFO_CTL_REG              0x18
57 #define SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_MASK   0xff
58 #define SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_BITS   0
59 #define SUN6I_FIFO_CTL_RF_RST                   BIT(15)
60 #define SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_MASK   0xff
61 #define SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_BITS   16
62 #define SUN6I_FIFO_CTL_TF_RST                   BIT(31)
63
64 #define SUN6I_FIFO_STA_REG              0x1c
65 #define SUN6I_FIFO_STA_RF_CNT_MASK              0x7f
66 #define SUN6I_FIFO_STA_RF_CNT_BITS              0
67 #define SUN6I_FIFO_STA_TF_CNT_MASK              0x7f
68 #define SUN6I_FIFO_STA_TF_CNT_BITS              16
69
70 #define SUN6I_CLK_CTL_REG               0x24
71 #define SUN6I_CLK_CTL_CDR2_MASK                 0xff
72 #define SUN6I_CLK_CTL_CDR2(div)                 (((div) & SUN6I_CLK_CTL_CDR2_MASK) << 0)
73 #define SUN6I_CLK_CTL_CDR1_MASK                 0xf
74 #define SUN6I_CLK_CTL_CDR1(div)                 (((div) & SUN6I_CLK_CTL_CDR1_MASK) << 8)
75 #define SUN6I_CLK_CTL_DRS                       BIT(12)
76
77 #define SUN6I_MAX_XFER_SIZE             0xffffff
78
79 #define SUN6I_BURST_CNT_REG             0x30
80 #define SUN6I_BURST_CNT(cnt)                    ((cnt) & SUN6I_MAX_XFER_SIZE)
81
82 #define SUN6I_XMIT_CNT_REG              0x34
83 #define SUN6I_XMIT_CNT(cnt)                     ((cnt) & SUN6I_MAX_XFER_SIZE)
84
85 #define SUN6I_BURST_CTL_CNT_REG         0x38
86 #define SUN6I_BURST_CTL_CNT_STC(cnt)            ((cnt) & SUN6I_MAX_XFER_SIZE)
87
88 #define SUN6I_TXDATA_REG                0x200
89 #define SUN6I_RXDATA_REG                0x300
90
91 struct sun6i_spi {
92         struct spi_master       *master;
93         void __iomem            *base_addr;
94         struct clk              *hclk;
95         struct clk              *mclk;
96         struct reset_control    *rstc;
97
98         struct completion       done;
99
100         const u8                *tx_buf;
101         u8                      *rx_buf;
102         int                     len;
103         unsigned long           fifo_depth;
104 };
105
106 static inline u32 sun6i_spi_read(struct sun6i_spi *sspi, u32 reg)
107 {
108         return readl(sspi->base_addr + reg);
109 }
110
111 static inline void sun6i_spi_write(struct sun6i_spi *sspi, u32 reg, u32 value)
112 {
113         writel(value, sspi->base_addr + reg);
114 }
115
116 static inline u32 sun6i_spi_get_tx_fifo_count(struct sun6i_spi *sspi)
117 {
118         u32 reg = sun6i_spi_read(sspi, SUN6I_FIFO_STA_REG);
119
120         reg >>= SUN6I_FIFO_STA_TF_CNT_BITS;
121
122         return reg & SUN6I_FIFO_STA_TF_CNT_MASK;
123 }
124
125 static inline void sun6i_spi_enable_interrupt(struct sun6i_spi *sspi, u32 mask)
126 {
127         u32 reg = sun6i_spi_read(sspi, SUN6I_INT_CTL_REG);
128
129         reg |= mask;
130         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, reg);
131 }
132
133 static inline void sun6i_spi_disable_interrupt(struct sun6i_spi *sspi, u32 mask)
134 {
135         u32 reg = sun6i_spi_read(sspi, SUN6I_INT_CTL_REG);
136
137         reg &= ~mask;
138         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, reg);
139 }
140
141 static inline void sun6i_spi_drain_fifo(struct sun6i_spi *sspi, int len)
142 {
143         u32 reg, cnt;
144         u8 byte;
145
146         /* See how much data is available */
147         reg = sun6i_spi_read(sspi, SUN6I_FIFO_STA_REG);
148         reg &= SUN6I_FIFO_STA_RF_CNT_MASK;
149         cnt = reg >> SUN6I_FIFO_STA_RF_CNT_BITS;
150
151         if (len > cnt)
152                 len = cnt;
153
154         while (len--) {
155                 byte = readb(sspi->base_addr + SUN6I_RXDATA_REG);
156                 if (sspi->rx_buf)
157                         *sspi->rx_buf++ = byte;
158         }
159 }
160
161 static inline void sun6i_spi_fill_fifo(struct sun6i_spi *sspi, int len)
162 {
163         u32 cnt;
164         u8 byte;
165
166         /* See how much data we can fit */
167         cnt = sspi->fifo_depth - sun6i_spi_get_tx_fifo_count(sspi);
168
169         len = min3(len, (int)cnt, sspi->len);
170
171         while (len--) {
172                 byte = sspi->tx_buf ? *sspi->tx_buf++ : 0;
173                 writeb(byte, sspi->base_addr + SUN6I_TXDATA_REG);
174                 sspi->len--;
175         }
176 }
177
178 static void sun6i_spi_set_cs(struct spi_device *spi, bool enable)
179 {
180         struct sun6i_spi *sspi = spi_master_get_devdata(spi->master);
181         u32 reg;
182
183         reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
184         reg &= ~SUN6I_TFR_CTL_CS_MASK;
185         reg |= SUN6I_TFR_CTL_CS(spi->chip_select);
186
187         if (enable)
188                 reg |= SUN6I_TFR_CTL_CS_LEVEL;
189         else
190                 reg &= ~SUN6I_TFR_CTL_CS_LEVEL;
191
192         sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg);
193 }
194
195 static size_t sun6i_spi_max_transfer_size(struct spi_device *spi)
196 {
197         return SUN6I_MAX_XFER_SIZE - 1;
198 }
199
200 static int sun6i_spi_transfer_one(struct spi_master *master,
201                                   struct spi_device *spi,
202                                   struct spi_transfer *tfr)
203 {
204         struct sun6i_spi *sspi = spi_master_get_devdata(master);
205         unsigned int mclk_rate, div, timeout;
206         unsigned int start, end, tx_time;
207         unsigned int trig_level;
208         unsigned int tx_len = 0;
209         int ret = 0;
210         u32 reg;
211
212         if (tfr->len > SUN6I_MAX_XFER_SIZE)
213                 return -EINVAL;
214
215         reinit_completion(&sspi->done);
216         sspi->tx_buf = tfr->tx_buf;
217         sspi->rx_buf = tfr->rx_buf;
218         sspi->len = tfr->len;
219
220         /* Clear pending interrupts */
221         sun6i_spi_write(sspi, SUN6I_INT_STA_REG, ~0);
222
223         /* Reset FIFO */
224         sun6i_spi_write(sspi, SUN6I_FIFO_CTL_REG,
225                         SUN6I_FIFO_CTL_RF_RST | SUN6I_FIFO_CTL_TF_RST);
226
227         /*
228          * Setup FIFO interrupt trigger level
229          * Here we choose 3/4 of the full fifo depth, as it's the hardcoded
230          * value used in old generation of Allwinner SPI controller.
231          * (See spi-sun4i.c)
232          */
233         trig_level = sspi->fifo_depth / 4 * 3;
234         sun6i_spi_write(sspi, SUN6I_FIFO_CTL_REG,
235                         (trig_level << SUN6I_FIFO_CTL_RF_RDY_TRIG_LEVEL_BITS) |
236                         (trig_level << SUN6I_FIFO_CTL_TF_ERQ_TRIG_LEVEL_BITS));
237
238         /*
239          * Setup the transfer control register: Chip Select,
240          * polarities, etc.
241          */
242         reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
243
244         if (spi->mode & SPI_CPOL)
245                 reg |= SUN6I_TFR_CTL_CPOL;
246         else
247                 reg &= ~SUN6I_TFR_CTL_CPOL;
248
249         if (spi->mode & SPI_CPHA)
250                 reg |= SUN6I_TFR_CTL_CPHA;
251         else
252                 reg &= ~SUN6I_TFR_CTL_CPHA;
253
254         if (spi->mode & SPI_LSB_FIRST)
255                 reg |= SUN6I_TFR_CTL_FBS;
256         else
257                 reg &= ~SUN6I_TFR_CTL_FBS;
258
259         /*
260          * If it's a TX only transfer, we don't want to fill the RX
261          * FIFO with bogus data
262          */
263         if (sspi->rx_buf)
264                 reg &= ~SUN6I_TFR_CTL_DHB;
265         else
266                 reg |= SUN6I_TFR_CTL_DHB;
267
268         /* We want to control the chip select manually */
269         reg |= SUN6I_TFR_CTL_CS_MANUAL;
270
271         sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg);
272
273         /* Ensure that we have a parent clock fast enough */
274         mclk_rate = clk_get_rate(sspi->mclk);
275         if (mclk_rate < (2 * tfr->speed_hz)) {
276                 clk_set_rate(sspi->mclk, 2 * tfr->speed_hz);
277                 mclk_rate = clk_get_rate(sspi->mclk);
278         }
279
280         /*
281          * Setup clock divider.
282          *
283          * We have two choices there. Either we can use the clock
284          * divide rate 1, which is calculated thanks to this formula:
285          * SPI_CLK = MOD_CLK / (2 ^ cdr)
286          * Or we can use CDR2, which is calculated with the formula:
287          * SPI_CLK = MOD_CLK / (2 * (cdr + 1))
288          * Wether we use the former or the latter is set through the
289          * DRS bit.
290          *
291          * First try CDR2, and if we can't reach the expected
292          * frequency, fall back to CDR1.
293          */
294         div = mclk_rate / (2 * tfr->speed_hz);
295         if (div <= (SUN6I_CLK_CTL_CDR2_MASK + 1)) {
296                 if (div > 0)
297                         div--;
298
299                 reg = SUN6I_CLK_CTL_CDR2(div) | SUN6I_CLK_CTL_DRS;
300         } else {
301                 div = ilog2(mclk_rate) - ilog2(tfr->speed_hz);
302                 reg = SUN6I_CLK_CTL_CDR1(div);
303         }
304
305         sun6i_spi_write(sspi, SUN6I_CLK_CTL_REG, reg);
306
307         /* Setup the transfer now... */
308         if (sspi->tx_buf)
309                 tx_len = tfr->len;
310
311         /* Setup the counters */
312         sun6i_spi_write(sspi, SUN6I_BURST_CNT_REG, SUN6I_BURST_CNT(tfr->len));
313         sun6i_spi_write(sspi, SUN6I_XMIT_CNT_REG, SUN6I_XMIT_CNT(tx_len));
314         sun6i_spi_write(sspi, SUN6I_BURST_CTL_CNT_REG,
315                         SUN6I_BURST_CTL_CNT_STC(tx_len));
316
317         /* Fill the TX FIFO */
318         sun6i_spi_fill_fifo(sspi, sspi->fifo_depth);
319
320         /* Enable the interrupts */
321         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, SUN6I_INT_CTL_TC);
322         sun6i_spi_enable_interrupt(sspi, SUN6I_INT_CTL_TC |
323                                          SUN6I_INT_CTL_RF_RDY);
324         if (tx_len > sspi->fifo_depth)
325                 sun6i_spi_enable_interrupt(sspi, SUN6I_INT_CTL_TF_ERQ);
326
327         /* Start the transfer */
328         reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
329         sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg | SUN6I_TFR_CTL_XCH);
330
331         tx_time = max(tfr->len * 8 * 2 / (tfr->speed_hz / 1000), 100U);
332         start = jiffies;
333         timeout = wait_for_completion_timeout(&sspi->done,
334                                               msecs_to_jiffies(tx_time));
335         end = jiffies;
336         if (!timeout) {
337                 dev_warn(&master->dev,
338                          "%s: timeout transferring %u bytes@%iHz for %i(%i)ms",
339                          dev_name(&spi->dev), tfr->len, tfr->speed_hz,
340                          jiffies_to_msecs(end - start), tx_time);
341                 ret = -ETIMEDOUT;
342                 goto out;
343         }
344
345 out:
346         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, 0);
347
348         return ret;
349 }
350
351 static irqreturn_t sun6i_spi_handler(int irq, void *dev_id)
352 {
353         struct sun6i_spi *sspi = dev_id;
354         u32 status = sun6i_spi_read(sspi, SUN6I_INT_STA_REG);
355
356         /* Transfer complete */
357         if (status & SUN6I_INT_CTL_TC) {
358                 sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_TC);
359                 sun6i_spi_drain_fifo(sspi, sspi->fifo_depth);
360                 complete(&sspi->done);
361                 return IRQ_HANDLED;
362         }
363
364         /* Receive FIFO 3/4 full */
365         if (status & SUN6I_INT_CTL_RF_RDY) {
366                 sun6i_spi_drain_fifo(sspi, SUN6I_FIFO_DEPTH);
367                 /* Only clear the interrupt _after_ draining the FIFO */
368                 sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_RF_RDY);
369                 return IRQ_HANDLED;
370         }
371
372         /* Transmit FIFO 3/4 empty */
373         if (status & SUN6I_INT_CTL_TF_ERQ) {
374                 sun6i_spi_fill_fifo(sspi, SUN6I_FIFO_DEPTH);
375
376                 if (!sspi->len)
377                         /* nothing left to transmit */
378                         sun6i_spi_disable_interrupt(sspi, SUN6I_INT_CTL_TF_ERQ);
379
380                 /* Only clear the interrupt _after_ re-seeding the FIFO */
381                 sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_TF_ERQ);
382
383                 return IRQ_HANDLED;
384         }
385
386         return IRQ_NONE;
387 }
388
389 static int sun6i_spi_runtime_resume(struct device *dev)
390 {
391         struct spi_master *master = dev_get_drvdata(dev);
392         struct sun6i_spi *sspi = spi_master_get_devdata(master);
393         int ret;
394
395         ret = clk_prepare_enable(sspi->hclk);
396         if (ret) {
397                 dev_err(dev, "Couldn't enable AHB clock\n");
398                 goto out;
399         }
400
401         ret = clk_prepare_enable(sspi->mclk);
402         if (ret) {
403                 dev_err(dev, "Couldn't enable module clock\n");
404                 goto err;
405         }
406
407         ret = reset_control_deassert(sspi->rstc);
408         if (ret) {
409                 dev_err(dev, "Couldn't deassert the device from reset\n");
410                 goto err2;
411         }
412
413         sun6i_spi_write(sspi, SUN6I_GBL_CTL_REG,
414                         SUN6I_GBL_CTL_BUS_ENABLE | SUN6I_GBL_CTL_MASTER | SUN6I_GBL_CTL_TP);
415
416         return 0;
417
418 err2:
419         clk_disable_unprepare(sspi->mclk);
420 err:
421         clk_disable_unprepare(sspi->hclk);
422 out:
423         return ret;
424 }
425
426 static int sun6i_spi_runtime_suspend(struct device *dev)
427 {
428         struct spi_master *master = dev_get_drvdata(dev);
429         struct sun6i_spi *sspi = spi_master_get_devdata(master);
430
431         reset_control_assert(sspi->rstc);
432         clk_disable_unprepare(sspi->mclk);
433         clk_disable_unprepare(sspi->hclk);
434
435         return 0;
436 }
437
438 static int sun6i_spi_probe(struct platform_device *pdev)
439 {
440         struct spi_master *master;
441         struct sun6i_spi *sspi;
442         struct resource *res;
443         int ret = 0, irq;
444
445         master = spi_alloc_master(&pdev->dev, sizeof(struct sun6i_spi));
446         if (!master) {
447                 dev_err(&pdev->dev, "Unable to allocate SPI Master\n");
448                 return -ENOMEM;
449         }
450
451         platform_set_drvdata(pdev, master);
452         sspi = spi_master_get_devdata(master);
453
454         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
455         sspi->base_addr = devm_ioremap_resource(&pdev->dev, res);
456         if (IS_ERR(sspi->base_addr)) {
457                 ret = PTR_ERR(sspi->base_addr);
458                 goto err_free_master;
459         }
460
461         irq = platform_get_irq(pdev, 0);
462         if (irq < 0) {
463                 dev_err(&pdev->dev, "No spi IRQ specified\n");
464                 ret = -ENXIO;
465                 goto err_free_master;
466         }
467
468         ret = devm_request_irq(&pdev->dev, irq, sun6i_spi_handler,
469                                0, "sun6i-spi", sspi);
470         if (ret) {
471                 dev_err(&pdev->dev, "Cannot request IRQ\n");
472                 goto err_free_master;
473         }
474
475         sspi->master = master;
476         sspi->fifo_depth = (unsigned long)of_device_get_match_data(&pdev->dev);
477
478         master->max_speed_hz = 100 * 1000 * 1000;
479         master->min_speed_hz = 3 * 1000;
480         master->set_cs = sun6i_spi_set_cs;
481         master->transfer_one = sun6i_spi_transfer_one;
482         master->num_chipselect = 4;
483         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
484         master->bits_per_word_mask = SPI_BPW_MASK(8);
485         master->dev.of_node = pdev->dev.of_node;
486         master->auto_runtime_pm = true;
487         master->max_transfer_size = sun6i_spi_max_transfer_size;
488
489         sspi->hclk = devm_clk_get(&pdev->dev, "ahb");
490         if (IS_ERR(sspi->hclk)) {
491                 dev_err(&pdev->dev, "Unable to acquire AHB clock\n");
492                 ret = PTR_ERR(sspi->hclk);
493                 goto err_free_master;
494         }
495
496         sspi->mclk = devm_clk_get(&pdev->dev, "mod");
497         if (IS_ERR(sspi->mclk)) {
498                 dev_err(&pdev->dev, "Unable to acquire module clock\n");
499                 ret = PTR_ERR(sspi->mclk);
500                 goto err_free_master;
501         }
502
503         init_completion(&sspi->done);
504
505         sspi->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
506         if (IS_ERR(sspi->rstc)) {
507                 dev_err(&pdev->dev, "Couldn't get reset controller\n");
508                 ret = PTR_ERR(sspi->rstc);
509                 goto err_free_master;
510         }
511
512         /*
513          * This wake-up/shutdown pattern is to be able to have the
514          * device woken up, even if runtime_pm is disabled
515          */
516         ret = sun6i_spi_runtime_resume(&pdev->dev);
517         if (ret) {
518                 dev_err(&pdev->dev, "Couldn't resume the device\n");
519                 goto err_free_master;
520         }
521
522         pm_runtime_set_active(&pdev->dev);
523         pm_runtime_enable(&pdev->dev);
524         pm_runtime_idle(&pdev->dev);
525
526         ret = devm_spi_register_master(&pdev->dev, master);
527         if (ret) {
528                 dev_err(&pdev->dev, "cannot register SPI master\n");
529                 goto err_pm_disable;
530         }
531
532         return 0;
533
534 err_pm_disable:
535         pm_runtime_disable(&pdev->dev);
536         sun6i_spi_runtime_suspend(&pdev->dev);
537 err_free_master:
538         spi_master_put(master);
539         return ret;
540 }
541
542 static int sun6i_spi_remove(struct platform_device *pdev)
543 {
544         pm_runtime_force_suspend(&pdev->dev);
545
546         return 0;
547 }
548
549 static const struct of_device_id sun6i_spi_match[] = {
550         { .compatible = "allwinner,sun6i-a31-spi", .data = (void *)SUN6I_FIFO_DEPTH },
551         { .compatible = "allwinner,sun8i-h3-spi",  .data = (void *)SUN8I_FIFO_DEPTH },
552         {}
553 };
554 MODULE_DEVICE_TABLE(of, sun6i_spi_match);
555
556 static const struct dev_pm_ops sun6i_spi_pm_ops = {
557         .runtime_resume         = sun6i_spi_runtime_resume,
558         .runtime_suspend        = sun6i_spi_runtime_suspend,
559 };
560
561 static struct platform_driver sun6i_spi_driver = {
562         .probe  = sun6i_spi_probe,
563         .remove = sun6i_spi_remove,
564         .driver = {
565                 .name           = "sun6i-spi",
566                 .of_match_table = sun6i_spi_match,
567                 .pm             = &sun6i_spi_pm_ops,
568         },
569 };
570 module_platform_driver(sun6i_spi_driver);
571
572 MODULE_AUTHOR("Pan Nan <pannan@allwinnertech.com>");
573 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
574 MODULE_DESCRIPTION("Allwinner A31 SPI controller driver");
575 MODULE_LICENSE("GPL");