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