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14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/types.h>
17#include <linux/errno.h>
18#include <linux/interrupt.h>
19#include <linux/of_address.h>
20#include <linux/of_platform.h>
21#include <linux/workqueue.h>
22#include <linux/completion.h>
23#include <linux/io.h>
24#include <linux/delay.h>
25#include <linux/spi/spi.h>
26#include <linux/fsl_devices.h>
27#include <linux/slab.h>
28
29#include <asm/mpc52xx.h>
30#include <asm/mpc52xx_psc.h>
31
32#define MCLK 20000000
33
34struct mpc52xx_psc_spi {
35
36 void (*cs_control)(struct spi_device *spi, bool on);
37 u32 sysclk;
38
39
40 struct mpc52xx_psc __iomem *psc;
41 struct mpc52xx_psc_fifo __iomem *fifo;
42 unsigned int irq;
43 u8 bits_per_word;
44 u8 busy;
45
46 struct workqueue_struct *workqueue;
47 struct work_struct work;
48
49 struct list_head queue;
50 spinlock_t lock;
51
52 struct completion done;
53};
54
55
56struct mpc52xx_psc_spi_cs {
57 int bits_per_word;
58 int speed_hz;
59};
60
61
62
63
64static int mpc52xx_psc_spi_transfer_setup(struct spi_device *spi,
65 struct spi_transfer *t)
66{
67 struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
68
69 cs->speed_hz = (t && t->speed_hz)
70 ? t->speed_hz : spi->max_speed_hz;
71 cs->bits_per_word = (t && t->bits_per_word)
72 ? t->bits_per_word : spi->bits_per_word;
73 cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8;
74 return 0;
75}
76
77static void mpc52xx_psc_spi_activate_cs(struct spi_device *spi)
78{
79 struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
80 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
81 struct mpc52xx_psc __iomem *psc = mps->psc;
82 u32 sicr;
83 u16 ccr;
84
85 sicr = in_be32(&psc->sicr);
86
87
88 if (spi->mode & SPI_CPHA)
89 sicr |= 0x00001000;
90 else
91 sicr &= ~0x00001000;
92 if (spi->mode & SPI_CPOL)
93 sicr |= 0x00002000;
94 else
95 sicr &= ~0x00002000;
96
97 if (spi->mode & SPI_LSB_FIRST)
98 sicr |= 0x10000000;
99 else
100 sicr &= ~0x10000000;
101 out_be32(&psc->sicr, sicr);
102
103
104
105
106
107 ccr = in_be16((u16 __iomem *)&psc->ccr);
108 ccr &= 0xFF00;
109 if (cs->speed_hz)
110 ccr |= (MCLK / cs->speed_hz - 1) & 0xFF;
111 else
112 ccr |= (MCLK / 1000000 - 1) & 0xFF;
113 out_be16((u16 __iomem *)&psc->ccr, ccr);
114 mps->bits_per_word = cs->bits_per_word;
115
116 if (mps->cs_control)
117 mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
118}
119
120static void mpc52xx_psc_spi_deactivate_cs(struct spi_device *spi)
121{
122 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
123
124 if (mps->cs_control)
125 mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
126}
127
128#define MPC52xx_PSC_BUFSIZE (MPC52xx_PSC_RFNUM_MASK + 1)
129
130#define MPC52xx_PSC_RFALARM (MPC52xx_PSC_BUFSIZE * 20 / 100)
131
132static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi,
133 struct spi_transfer *t)
134{
135 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
136 struct mpc52xx_psc __iomem *psc = mps->psc;
137 struct mpc52xx_psc_fifo __iomem *fifo = mps->fifo;
138 unsigned rb = 0;
139 unsigned sb = 0;
140 unsigned char *rx_buf = (unsigned char *)t->rx_buf;
141 unsigned char *tx_buf = (unsigned char *)t->tx_buf;
142 unsigned rfalarm;
143 unsigned send_at_once = MPC52xx_PSC_BUFSIZE;
144 unsigned recv_at_once;
145 int last_block = 0;
146
147 if (!t->tx_buf && !t->rx_buf && t->len)
148 return -EINVAL;
149
150
151 out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
152 while (rb < t->len) {
153 if (t->len - rb > MPC52xx_PSC_BUFSIZE) {
154 rfalarm = MPC52xx_PSC_RFALARM;
155 last_block = 0;
156 } else {
157 send_at_once = t->len - sb;
158 rfalarm = MPC52xx_PSC_BUFSIZE - (t->len - rb);
159 last_block = 1;
160 }
161
162 dev_dbg(&spi->dev, "send %d bytes...\n", send_at_once);
163 for (; send_at_once; sb++, send_at_once--) {
164
165 if (send_at_once == 1 && last_block)
166 out_8(&psc->ircr2, 0x01);
167
168 if (tx_buf)
169 out_8(&psc->mpc52xx_psc_buffer_8, tx_buf[sb]);
170 else
171 out_8(&psc->mpc52xx_psc_buffer_8, 0);
172 }
173
174
175
176
177
178
179 out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
180 if (t->len - rb == 1) {
181 out_8(&psc->mode, 0);
182 } else {
183 out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
184 out_be16(&fifo->rfalarm, rfalarm);
185 }
186 out_be16(&psc->mpc52xx_psc_imr, MPC52xx_PSC_IMR_RXRDY);
187 wait_for_completion(&mps->done);
188 recv_at_once = in_be16(&fifo->rfnum);
189 dev_dbg(&spi->dev, "%d bytes received\n", recv_at_once);
190
191 send_at_once = recv_at_once;
192 if (rx_buf) {
193 for (; recv_at_once; rb++, recv_at_once--)
194 rx_buf[rb] = in_8(&psc->mpc52xx_psc_buffer_8);
195 } else {
196 for (; recv_at_once; rb++, recv_at_once--)
197 in_8(&psc->mpc52xx_psc_buffer_8);
198 }
199 }
200
201 out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
202
203 return 0;
204}
205
206static void mpc52xx_psc_spi_work(struct work_struct *work)
207{
208 struct mpc52xx_psc_spi *mps =
209 container_of(work, struct mpc52xx_psc_spi, work);
210
211 spin_lock_irq(&mps->lock);
212 mps->busy = 1;
213 while (!list_empty(&mps->queue)) {
214 struct spi_message *m;
215 struct spi_device *spi;
216 struct spi_transfer *t = NULL;
217 unsigned cs_change;
218 int status;
219
220 m = container_of(mps->queue.next, struct spi_message, queue);
221 list_del_init(&m->queue);
222 spin_unlock_irq(&mps->lock);
223
224 spi = m->spi;
225 cs_change = 1;
226 status = 0;
227 list_for_each_entry (t, &m->transfers, transfer_list) {
228 if (t->bits_per_word || t->speed_hz) {
229 status = mpc52xx_psc_spi_transfer_setup(spi, t);
230 if (status < 0)
231 break;
232 }
233
234 if (cs_change)
235 mpc52xx_psc_spi_activate_cs(spi);
236 cs_change = t->cs_change;
237
238 status = mpc52xx_psc_spi_transfer_rxtx(spi, t);
239 if (status)
240 break;
241 m->actual_length += t->len;
242
243 if (t->delay_usecs)
244 udelay(t->delay_usecs);
245
246 if (cs_change)
247 mpc52xx_psc_spi_deactivate_cs(spi);
248 }
249
250 m->status = status;
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, "probe called without platform data, no "
387 "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 .owner = THIS_MODULE,
512 .of_match_table = mpc52xx_psc_spi_of_match,
513 },
514};
515module_platform_driver(mpc52xx_psc_spi_of_driver);
516
517MODULE_AUTHOR("Dragos Carp");
518MODULE_DESCRIPTION("MPC52xx PSC SPI Driver");
519MODULE_LICENSE("GPL");
520
