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14#include <linux/module.h>
15#include <linux/types.h>
16#include <linux/errno.h>
17#include <linux/interrupt.h>
18#include <linux/of_address.h>
19#include <linux/of_platform.h>
20#include <linux/workqueue.h>
21#include <linux/completion.h>
22#include <linux/io.h>
23#include <linux/delay.h>
24#include <linux/spi/spi.h>
25#include <linux/fsl_devices.h>
26#include <linux/slab.h>
27
28#include <asm/mpc52xx.h>
29#include <asm/mpc52xx_psc.h>
30
31#define MCLK 20000000
32
33struct mpc52xx_psc_spi {
34
35 void (*cs_control)(struct spi_device *spi, bool on);
36 u32 sysclk;
37
38
39 struct mpc52xx_psc __iomem *psc;
40 struct mpc52xx_psc_fifo __iomem *fifo;
41 unsigned int irq;
42 u8 bits_per_word;
43 u8 busy;
44
45 struct workqueue_struct *workqueue;
46 struct work_struct work;
47
48 struct list_head queue;
49 spinlock_t lock;
50
51 struct completion done;
52};
53
54
55struct mpc52xx_psc_spi_cs {
56 int bits_per_word;
57 int speed_hz;
58};
59
60
61
62
63static int mpc52xx_psc_spi_transfer_setup(struct spi_device *spi,
64 struct spi_transfer *t)
65{
66 struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
67
68 cs->speed_hz = (t && t->speed_hz)
69 ? t->speed_hz : spi->max_speed_hz;
70 cs->bits_per_word = (t && t->bits_per_word)
71 ? t->bits_per_word : spi->bits_per_word;
72 cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8;
73 return 0;
74}
75
76static void mpc52xx_psc_spi_activate_cs(struct spi_device *spi)
77{
78 struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
79 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
80 struct mpc52xx_psc __iomem *psc = mps->psc;
81 u32 sicr;
82 u16 ccr;
83
84 sicr = in_be32(&psc->sicr);
85
86
87 if (spi->mode & SPI_CPHA)
88 sicr |= 0x00001000;
89 else
90 sicr &= ~0x00001000;
91 if (spi->mode & SPI_CPOL)
92 sicr |= 0x00002000;
93 else
94 sicr &= ~0x00002000;
95
96 if (spi->mode & SPI_LSB_FIRST)
97 sicr |= 0x10000000;
98 else
99 sicr &= ~0x10000000;
100 out_be32(&psc->sicr, sicr);
101
102
103
104
105
106 ccr = in_be16((u16 __iomem *)&psc->ccr);
107 ccr &= 0xFF00;
108 if (cs->speed_hz)
109 ccr |= (MCLK / cs->speed_hz - 1) & 0xFF;
110 else
111 ccr |= (MCLK / 1000000 - 1) & 0xFF;
112 out_be16((u16 __iomem *)&psc->ccr, ccr);
113 mps->bits_per_word = cs->bits_per_word;
114
115 if (mps->cs_control)
116 mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
117}
118
119static void mpc52xx_psc_spi_deactivate_cs(struct spi_device *spi)
120{
121 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
122
123 if (mps->cs_control)
124 mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
125}
126
127#define MPC52xx_PSC_BUFSIZE (MPC52xx_PSC_RFNUM_MASK + 1)
128
129#define MPC52xx_PSC_RFALARM (MPC52xx_PSC_BUFSIZE * 20 / 100)
130
131static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi,
132 struct spi_transfer *t)
133{
134 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
135 struct mpc52xx_psc __iomem *psc = mps->psc;
136 struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
137 unsigned rb = 0;
138 unsigned sb = 0;
139 unsigned char *rx_buf = (unsigned char *)t->rx_buf;
140 unsigned char *tx_buf = (unsigned char *)t->tx_buf;
141 unsigned rfalarm;
142 unsigned send_at_once = MPC52xx_PSC_BUFSIZE;
143 unsigned recv_at_once;
144 int last_block = 0;
145
146 if (!t->tx_buf && !t->rx_buf && t->len)
147 return -EINVAL;
148
149
150 out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
151 while (rb < t->len) {
152 if (t->len - rb > MPC52xx_PSC_BUFSIZE) {
153 rfalarm = MPC52xx_PSC_RFALARM;
154 last_block = 0;
155 } else {
156 send_at_once = t->len - sb;
157 rfalarm = MPC52xx_PSC_BUFSIZE - (t->len - rb);
158 last_block = 1;
159 }
160
161 dev_dbg(&spi->dev, "send %d bytes...\n", send_at_once);
162 for (; send_at_once; sb++, send_at_once--) {
163
164 if (send_at_once == 1 && last_block)
165 out_8(&psc->ircr2, 0x01);
166
167 if (tx_buf)
168 out_8(&psc->mpc52xx_psc_buffer_8, tx_buf[sb]);
169 else
170 out_8(&psc->mpc52xx_psc_buffer_8, 0);
171 }
172
173
174
175
176
177
178 out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
179 if (t->len - rb == 1) {
180 out_8(&psc->mode, 0);
181 } else {
182 out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
183 out_be16(&fifo->rfalarm, rfalarm);
184 }
185 out_be16(&psc->mpc52xx_psc_imr, MPC52xx_PSC_IMR_RXRDY);
186 wait_for_completion(&mps->done);
187 recv_at_once = in_be16(&fifo->rfnum);
188 dev_dbg(&spi->dev, "%d bytes received\n", recv_at_once);
189
190 send_at_once = recv_at_once;
191 if (rx_buf) {
192 for (; recv_at_once; rb++, recv_at_once--)
193 rx_buf[rb] = in_8(&psc->mpc52xx_psc_buffer_8);
194 } else {
195 for (; recv_at_once; rb++, recv_at_once--)
196 in_8(&psc->mpc52xx_psc_buffer_8);
197 }
198 }
199
200 out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
201
202 return 0;
203}
204
205static void mpc52xx_psc_spi_work(struct work_struct *work)
206{
207 struct mpc52xx_psc_spi *mps =
208 container_of(work, struct mpc52xx_psc_spi, work);
209
210 spin_lock_irq(&mps->lock);
211 mps->busy = 1;
212 while (!list_empty(&mps->queue)) {
213 struct spi_message *m;
214 struct spi_device *spi;
215 struct spi_transfer *t = NULL;
216 unsigned cs_change;
217 int status;
218
219 m = container_of(mps->queue.next, struct spi_message, queue);
220 list_del_init(&m->queue);
221 spin_unlock_irq(&mps->lock);
222
223 spi = m->spi;
224 cs_change = 1;
225 status = 0;
226 list_for_each_entry (t, &m->transfers, transfer_list) {
227 if (t->bits_per_word || t->speed_hz) {
228 status = mpc52xx_psc_spi_transfer_setup(spi, t);
229 if (status < 0)
230 break;
231 }
232
233 if (cs_change)
234 mpc52xx_psc_spi_activate_cs(spi);
235 cs_change = t->cs_change;
236
237 status = mpc52xx_psc_spi_transfer_rxtx(spi, t);
238 if (status)
239 break;
240 m->actual_length += t->len;
241
242 if (t->delay_usecs)
243 udelay(t->delay_usecs);
244
245 if (cs_change)
246 mpc52xx_psc_spi_deactivate_cs(spi);
247 }
248
249 m->status = status;
250 if (m->complete)
251 m->complete(m->context);
252
253 if (status || !cs_change)
254 mpc52xx_psc_spi_deactivate_cs(spi);
255
256 mpc52xx_psc_spi_transfer_setup(spi, NULL);
257
258 spin_lock_irq(&mps->lock);
259 }
260 mps->busy = 0;
261 spin_unlock_irq(&mps->lock);
262}
263
264static int mpc52xx_psc_spi_setup(struct spi_device *spi)
265{
266 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
267 struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
268 unsigned long flags;
269
270 if (spi->bits_per_word%8)
271 return -EINVAL;
272
273 if (!cs) {
274 cs = kzalloc(sizeof *cs, GFP_KERNEL);
275 if (!cs)
276 return -ENOMEM;
277 spi->controller_state = cs;
278 }
279
280 cs->bits_per_word = spi->bits_per_word;
281 cs->speed_hz = spi->max_speed_hz;
282
283 spin_lock_irqsave(&mps->lock, flags);
284 if (!mps->busy)
285 mpc52xx_psc_spi_deactivate_cs(spi);
286 spin_unlock_irqrestore(&mps->lock, flags);
287
288 return 0;
289}
290
291static int mpc52xx_psc_spi_transfer(struct spi_device *spi,
292 struct spi_message *m)
293{
294 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
295 unsigned long flags;
296
297 m->actual_length = 0;
298 m->status = -EINPROGRESS;
299
300 spin_lock_irqsave(&mps->lock, flags);
301 list_add_tail(&m->queue, &mps->queue);
302 queue_work(mps->workqueue, &mps->work);
303 spin_unlock_irqrestore(&mps->lock, flags);
304
305 return 0;
306}
307
308static void mpc52xx_psc_spi_cleanup(struct spi_device *spi)
309{
310 kfree(spi->controller_state);
311}
312
313static int mpc52xx_psc_spi_port_config(int psc_id, struct mpc52xx_psc_spi *mps)
314{
315 struct mpc52xx_psc __iomem *psc = mps->psc;
316 struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
317 u32 mclken_div;
318 int ret;
319
320
321 mclken_div = (mps->sysclk ? mps->sysclk : 512000000) / MCLK;
322 ret = mpc52xx_set_psc_clkdiv(psc_id, mclken_div);
323 if (ret)
324 return ret;
325
326
327 out_8(&psc->command, MPC52xx_PSC_RST_RX);
328 out_8(&psc->command, MPC52xx_PSC_RST_TX);
329 out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
330
331
332 out_be16(&psc->mpc52xx_psc_imr, 0);
333 out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
334 out_8(&fifo->rfcntl, 0);
335 out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
336
337
338
339 out_be32(&psc->sicr, 0x0180C800);
340 out_be16((u16 __iomem *)&psc->ccr, 0x070F);
341
342
343 out_8(&psc->ctur, 0x00);
344 out_8(&psc->ctlr, 0x84);
345
346 mps->bits_per_word = 8;
347
348 return 0;
349}
350
351static irqreturn_t mpc52xx_psc_spi_isr(int irq, void *dev_id)
352{
353 struct mpc52xx_psc_spi *mps = (struct mpc52xx_psc_spi *)dev_id;
354 struct mpc52xx_psc __iomem *psc = mps->psc;
355
356
357 if (in_be16(&psc->mpc52xx_psc_isr) & MPC52xx_PSC_IMR_RXRDY) {
358 out_be16(&psc->mpc52xx_psc_imr, 0);
359 complete(&mps->done);
360 return IRQ_HANDLED;
361 }
362 return IRQ_NONE;
363}
364
365
366static int mpc52xx_psc_spi_do_probe(struct device *dev, u32 regaddr,
367 u32 size, unsigned int irq, s16 bus_num)
368{
369 struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
370 struct mpc52xx_psc_spi *mps;
371 struct spi_master *master;
372 int ret;
373
374 master = spi_alloc_master(dev, sizeof *mps);
375 if (master == NULL)
376 return -ENOMEM;
377
378 dev_set_drvdata(dev, master);
379 mps = spi_master_get_devdata(master);
380
381
382 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
383
384 mps->irq = irq;
385 if (pdata == NULL) {
386 dev_warn(dev,
387 "probe called without platform data, no cs_control function will be called\n");
388 mps->cs_control = NULL;
389 mps->sysclk = 0;
390 master->bus_num = bus_num;
391 master->num_chipselect = 255;
392 } else {
393 mps->cs_control = pdata->cs_control;
394 mps->sysclk = pdata->sysclk;
395 master->bus_num = pdata->bus_num;
396 master->num_chipselect = pdata->max_chipselect;
397 }
398 master->setup = mpc52xx_psc_spi_setup;
399 master->transfer = mpc52xx_psc_spi_transfer;
400 master->cleanup = mpc52xx_psc_spi_cleanup;
401 master->dev.of_node = dev->of_node;
402
403 mps->psc = ioremap(regaddr, size);
404 if (!mps->psc) {
405 dev_err(dev, "could not ioremap I/O port range\n");
406 ret = -EFAULT;
407 goto free_master;
408 }
409
410 mps->fifo = ((void __iomem *)mps->psc) + sizeof(struct mpc52xx_psc);
411
412 ret = request_irq(mps->irq, mpc52xx_psc_spi_isr, 0, "mpc52xx-psc-spi",
413 mps);
414 if (ret)
415 goto free_master;
416
417 ret = mpc52xx_psc_spi_port_config(master->bus_num, mps);
418 if (ret < 0) {
419 dev_err(dev, "can't configure PSC! Is it capable of SPI?\n");
420 goto free_irq;
421 }
422
423 spin_lock_init(&mps->lock);
424 init_completion(&mps->done);
425 INIT_WORK(&mps->work, mpc52xx_psc_spi_work);
426 INIT_LIST_HEAD(&mps->queue);
427
428 mps->workqueue = create_singlethread_workqueue(
429 dev_name(master->dev.parent));
430 if (mps->workqueue == NULL) {
431 ret = -EBUSY;
432 goto free_irq;
433 }
434
435 ret = spi_register_master(master);
436 if (ret < 0)
437 goto unreg_master;
438
439 return ret;
440
441unreg_master:
442 destroy_workqueue(mps->workqueue);
443free_irq:
444 free_irq(mps->irq, mps);
445free_master:
446 if (mps->psc)
447 iounmap(mps->psc);
448 spi_master_put(master);
449
450 return ret;
451}
452
453static int mpc52xx_psc_spi_of_probe(struct platform_device *op)
454{
455 const u32 *regaddr_p;
456 u64 regaddr64, size64;
457 s16 id = -1;
458
459 regaddr_p = of_get_address(op->dev.of_node, 0, &size64, NULL);
460 if (!regaddr_p) {
461 dev_err(&op->dev, "Invalid PSC address\n");
462 return -EINVAL;
463 }
464 regaddr64 = of_translate_address(op->dev.of_node, regaddr_p);
465
466
467 if (op->dev.platform_data == NULL) {
468 const u32 *psc_nump;
469
470 psc_nump = of_get_property(op->dev.of_node, "cell-index", NULL);
471 if (!psc_nump || *psc_nump > 5) {
472 dev_err(&op->dev, "Invalid cell-index property\n");
473 return -EINVAL;
474 }
475 id = *psc_nump + 1;
476 }
477
478 return mpc52xx_psc_spi_do_probe(&op->dev, (u32)regaddr64, (u32)size64,
479 irq_of_parse_and_map(op->dev.of_node, 0), id);
480}
481
482static int mpc52xx_psc_spi_of_remove(struct platform_device *op)
483{
484 struct spi_master *master = spi_master_get(platform_get_drvdata(op));
485 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(master);
486
487 flush_workqueue(mps->workqueue);
488 destroy_workqueue(mps->workqueue);
489 spi_unregister_master(master);
490 free_irq(mps->irq, mps);
491 if (mps->psc)
492 iounmap(mps->psc);
493 spi_master_put(master);
494
495 return 0;
496}
497
498static const struct of_device_id mpc52xx_psc_spi_of_match[] = {
499 { .compatible = "fsl,mpc5200-psc-spi", },
500 { .compatible = "mpc5200-psc-spi", },
501 {}
502};
503
504MODULE_DEVICE_TABLE(of, mpc52xx_psc_spi_of_match);
505
506static struct platform_driver mpc52xx_psc_spi_of_driver = {
507 .probe = mpc52xx_psc_spi_of_probe,
508 .remove = mpc52xx_psc_spi_of_remove,
509 .driver = {
510 .name = "mpc52xx-psc-spi",
511 .of_match_table = mpc52xx_psc_spi_of_match,
512 },
513};
514module_platform_driver(mpc52xx_psc_spi_of_driver);
515
516MODULE_AUTHOR("Dragos Carp");
517MODULE_DESCRIPTION("MPC52xx PSC SPI Driver");
518MODULE_LICENSE("GPL");
519
