Lines Matching +full:idle +full:- +full:wait +full:- +full:delay
1 // SPDX-License-Identifier: GPL-2.0-only
18 #include <linux/delay.h>
30 MODULE_DESCRIPTION("MPC52xx SPI (non-PSC) Driver");
103 if (ms->gpio_cs_count > 0) { in mpc52xx_spi_chipsel()
104 cs = ms->message->spi->chip_select; in mpc52xx_spi_chipsel()
105 gpiod_set_value(ms->gpio_cs[cs], value); in mpc52xx_spi_chipsel()
107 out_8(ms->regs + SPI_PORTDATA, value ? 0 : 0x08); in mpc52xx_spi_chipsel()
112 * Start a new transfer. This is called both by the idle state
113 * for the first transfer in a message, and by the wait state when the
118 ms->rx_buf = ms->transfer->rx_buf; in mpc52xx_spi_start_transfer()
119 ms->tx_buf = ms->transfer->tx_buf; in mpc52xx_spi_start_transfer()
120 ms->len = ms->transfer->len; in mpc52xx_spi_start_transfer()
123 if (ms->cs_change) in mpc52xx_spi_start_transfer()
125 ms->cs_change = ms->transfer->cs_change; in mpc52xx_spi_start_transfer()
128 ms->wcol_tx_timestamp = mftb(); in mpc52xx_spi_start_transfer()
129 if (ms->tx_buf) in mpc52xx_spi_start_transfer()
130 out_8(ms->regs + SPI_DATA, *ms->tx_buf++); in mpc52xx_spi_start_transfer()
132 out_8(ms->regs + SPI_DATA, 0); in mpc52xx_spi_start_transfer()
142 * IDLE state
155 dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n", in mpc52xx_spi_fsmstate_idle()
159 if (list_empty(&ms->queue)) in mpc52xx_spi_fsmstate_idle()
163 ms->message = list_first_entry(&ms->queue, struct spi_message, queue); in mpc52xx_spi_fsmstate_idle()
164 list_del_init(&ms->message->queue); in mpc52xx_spi_fsmstate_idle()
168 spi = ms->message->spi; in mpc52xx_spi_fsmstate_idle()
169 if (spi->mode & SPI_CPHA) in mpc52xx_spi_fsmstate_idle()
171 if (spi->mode & SPI_CPOL) in mpc52xx_spi_fsmstate_idle()
173 if (spi->mode & SPI_LSB_FIRST) in mpc52xx_spi_fsmstate_idle()
175 out_8(ms->regs + SPI_CTRL1, ctrl1); in mpc52xx_spi_fsmstate_idle()
180 sppr = ((ms->ipb_freq / ms->message->spi->max_speed_hz) + 1) >> 1; in mpc52xx_spi_fsmstate_idle()
184 while (((sppr - 1) & ~0x7) != 0) { in mpc52xx_spi_fsmstate_idle()
188 sppr--; /* sppr quantity in register is offset by 1 */ in mpc52xx_spi_fsmstate_idle()
194 out_8(ms->regs + SPI_BRR, sppr << 4 | spr); /* Set speed */ in mpc52xx_spi_fsmstate_idle()
196 ms->cs_change = 1; in mpc52xx_spi_fsmstate_idle()
197 ms->transfer = container_of(ms->message->transfers.next, in mpc52xx_spi_fsmstate_idle()
201 ms->state = mpc52xx_spi_fsmstate_transfer; in mpc52xx_spi_fsmstate_idle()
211 * (unless this transfer is finished; in which case go on to the wait
218 return ms->irq0 ? FSM_STOP : FSM_POLL; in mpc52xx_spi_fsmstate_transfer()
224 * machine only). The manual recommends inserting a delay in mpc52xx_spi_fsmstate_transfer()
228 ms->wcol_count++; in mpc52xx_spi_fsmstate_transfer()
229 ms->wcol_ticks += mftb() - ms->wcol_tx_timestamp; in mpc52xx_spi_fsmstate_transfer()
230 ms->wcol_tx_timestamp = mftb(); in mpc52xx_spi_fsmstate_transfer()
232 if (ms->tx_buf) in mpc52xx_spi_fsmstate_transfer()
233 data = *(ms->tx_buf - 1); in mpc52xx_spi_fsmstate_transfer()
234 out_8(ms->regs + SPI_DATA, data); /* try again */ in mpc52xx_spi_fsmstate_transfer()
237 ms->modf_count++; in mpc52xx_spi_fsmstate_transfer()
238 dev_err(&ms->master->dev, "mode fault\n"); in mpc52xx_spi_fsmstate_transfer()
240 ms->message->status = -EIO; in mpc52xx_spi_fsmstate_transfer()
241 if (ms->message->complete) in mpc52xx_spi_fsmstate_transfer()
242 ms->message->complete(ms->message->context); in mpc52xx_spi_fsmstate_transfer()
243 ms->state = mpc52xx_spi_fsmstate_idle; in mpc52xx_spi_fsmstate_transfer()
248 ms->byte_count++; in mpc52xx_spi_fsmstate_transfer()
249 if (ms->rx_buf) in mpc52xx_spi_fsmstate_transfer()
250 *ms->rx_buf++ = data; in mpc52xx_spi_fsmstate_transfer()
253 ms->len--; in mpc52xx_spi_fsmstate_transfer()
254 if (ms->len == 0) { in mpc52xx_spi_fsmstate_transfer()
255 ms->timestamp = mftb(); in mpc52xx_spi_fsmstate_transfer()
256 if (ms->transfer->delay.unit == SPI_DELAY_UNIT_USECS) in mpc52xx_spi_fsmstate_transfer()
257 ms->timestamp += ms->transfer->delay.value * in mpc52xx_spi_fsmstate_transfer()
259 ms->state = mpc52xx_spi_fsmstate_wait; in mpc52xx_spi_fsmstate_transfer()
264 ms->wcol_tx_timestamp = mftb(); in mpc52xx_spi_fsmstate_transfer()
265 if (ms->tx_buf) in mpc52xx_spi_fsmstate_transfer()
266 out_8(ms->regs + SPI_DATA, *ms->tx_buf++); in mpc52xx_spi_fsmstate_transfer()
268 out_8(ms->regs + SPI_DATA, 0); in mpc52xx_spi_fsmstate_transfer()
274 * WAIT state
276 * A transfer has completed; need to wait for the delay period to complete
283 dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n", in mpc52xx_spi_fsmstate_wait()
286 if (((int)mftb()) - ms->timestamp < 0) in mpc52xx_spi_fsmstate_wait()
289 ms->message->actual_length += ms->transfer->len; in mpc52xx_spi_fsmstate_wait()
292 * aren't then deactivate CS, notify sender, and drop back to idle in mpc52xx_spi_fsmstate_wait()
294 if (ms->transfer->transfer_list.next == &ms->message->transfers) { in mpc52xx_spi_fsmstate_wait()
295 ms->msg_count++; in mpc52xx_spi_fsmstate_wait()
297 ms->message->status = 0; in mpc52xx_spi_fsmstate_wait()
298 if (ms->message->complete) in mpc52xx_spi_fsmstate_wait()
299 ms->message->complete(ms->message->context); in mpc52xx_spi_fsmstate_wait()
300 ms->state = mpc52xx_spi_fsmstate_idle; in mpc52xx_spi_fsmstate_wait()
306 if (ms->cs_change) in mpc52xx_spi_fsmstate_wait()
309 ms->transfer = container_of(ms->transfer->transfer_list.next, in mpc52xx_spi_fsmstate_wait()
312 ms->state = mpc52xx_spi_fsmstate_transfer; in mpc52xx_spi_fsmstate_wait()
317 * mpc52xx_spi_fsm_process - Finite State Machine iteration function
329 status = in_8(ms->regs + SPI_STATUS); in mpc52xx_spi_fsm_process()
330 data = in_8(ms->regs + SPI_DATA); in mpc52xx_spi_fsm_process()
331 rc = ms->state(irq, ms, status, data); in mpc52xx_spi_fsm_process()
335 schedule_work(&ms->work); in mpc52xx_spi_fsm_process()
339 * mpc52xx_spi_irq - IRQ handler
344 spin_lock(&ms->lock); in mpc52xx_spi_irq()
346 spin_unlock(&ms->lock); in mpc52xx_spi_irq()
351 * mpc52xx_spi_wq - Workqueue function for polling the state machine
358 spin_lock_irqsave(&ms->lock, flags); in mpc52xx_spi_wq()
360 spin_unlock_irqrestore(&ms->lock, flags); in mpc52xx_spi_wq()
369 struct mpc52xx_spi *ms = spi_master_get_devdata(spi->master); in mpc52xx_spi_transfer()
372 m->actual_length = 0; in mpc52xx_spi_transfer()
373 m->status = -EINPROGRESS; in mpc52xx_spi_transfer()
375 spin_lock_irqsave(&ms->lock, flags); in mpc52xx_spi_transfer()
376 list_add_tail(&m->queue, &ms->queue); in mpc52xx_spi_transfer()
377 spin_unlock_irqrestore(&ms->lock, flags); in mpc52xx_spi_transfer()
378 schedule_work(&ms->work); in mpc52xx_spi_transfer()
396 dev_dbg(&op->dev, "probing mpc5200 SPI device\n"); in mpc52xx_spi_probe()
397 regs = of_iomap(op->dev.of_node, 0); in mpc52xx_spi_probe()
399 return -ENODEV; in mpc52xx_spi_probe()
408 /* Clear the status register and re-read it to check for a MODF in mpc52xx_spi_probe()
417 dev_err(&op->dev, "mode fault; is port_config correct?\n"); in mpc52xx_spi_probe()
418 rc = -EIO; in mpc52xx_spi_probe()
422 dev_dbg(&op->dev, "allocating spi_master struct\n"); in mpc52xx_spi_probe()
423 master = spi_alloc_master(&op->dev, sizeof(*ms)); in mpc52xx_spi_probe()
425 rc = -ENOMEM; in mpc52xx_spi_probe()
429 master->transfer = mpc52xx_spi_transfer; in mpc52xx_spi_probe()
430 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST; in mpc52xx_spi_probe()
431 master->bits_per_word_mask = SPI_BPW_MASK(8); in mpc52xx_spi_probe()
432 master->dev.of_node = op->dev.of_node; in mpc52xx_spi_probe()
437 ms->master = master; in mpc52xx_spi_probe()
438 ms->regs = regs; in mpc52xx_spi_probe()
439 ms->irq0 = irq_of_parse_and_map(op->dev.of_node, 0); in mpc52xx_spi_probe()
440 ms->irq1 = irq_of_parse_and_map(op->dev.of_node, 1); in mpc52xx_spi_probe()
441 ms->state = mpc52xx_spi_fsmstate_idle; in mpc52xx_spi_probe()
442 ms->ipb_freq = mpc5xxx_get_bus_frequency(&op->dev); in mpc52xx_spi_probe()
443 ms->gpio_cs_count = gpiod_count(&op->dev, NULL); in mpc52xx_spi_probe()
444 if (ms->gpio_cs_count > 0) { in mpc52xx_spi_probe()
445 master->num_chipselect = ms->gpio_cs_count; in mpc52xx_spi_probe()
446 ms->gpio_cs = kmalloc_array(ms->gpio_cs_count, in mpc52xx_spi_probe()
447 sizeof(*ms->gpio_cs), in mpc52xx_spi_probe()
449 if (!ms->gpio_cs) { in mpc52xx_spi_probe()
450 rc = -ENOMEM; in mpc52xx_spi_probe()
454 for (i = 0; i < ms->gpio_cs_count; i++) { in mpc52xx_spi_probe()
455 gpio_cs = gpiod_get_index(&op->dev, in mpc52xx_spi_probe()
459 dev_err(&op->dev, in mpc52xx_spi_probe()
465 ms->gpio_cs[i] = gpio_cs; in mpc52xx_spi_probe()
469 spin_lock_init(&ms->lock); in mpc52xx_spi_probe()
470 INIT_LIST_HEAD(&ms->queue); in mpc52xx_spi_probe()
471 INIT_WORK(&ms->work, mpc52xx_spi_wq); in mpc52xx_spi_probe()
474 if (ms->irq0 && ms->irq1) { in mpc52xx_spi_probe()
475 rc = request_irq(ms->irq0, mpc52xx_spi_irq, 0, in mpc52xx_spi_probe()
476 "mpc5200-spi-modf", ms); in mpc52xx_spi_probe()
477 rc |= request_irq(ms->irq1, mpc52xx_spi_irq, 0, in mpc52xx_spi_probe()
478 "mpc5200-spi-spif", ms); in mpc52xx_spi_probe()
480 free_irq(ms->irq0, ms); in mpc52xx_spi_probe()
481 free_irq(ms->irq1, ms); in mpc52xx_spi_probe()
482 ms->irq0 = ms->irq1 = 0; in mpc52xx_spi_probe()
486 ms->irq0 = ms->irq1 = 0; in mpc52xx_spi_probe()
489 if (!ms->irq0) in mpc52xx_spi_probe()
490 dev_info(&op->dev, "using polled mode\n"); in mpc52xx_spi_probe()
492 dev_dbg(&op->dev, "registering spi_master struct\n"); in mpc52xx_spi_probe()
497 dev_info(&ms->master->dev, "registered MPC5200 SPI bus\n"); in mpc52xx_spi_probe()
502 dev_err(&ms->master->dev, "initialization failed\n"); in mpc52xx_spi_probe()
504 while (i-- > 0) in mpc52xx_spi_probe()
505 gpiod_put(ms->gpio_cs[i]); in mpc52xx_spi_probe()
507 kfree(ms->gpio_cs); in mpc52xx_spi_probe()
522 free_irq(ms->irq0, ms); in mpc52xx_spi_remove()
523 free_irq(ms->irq1, ms); in mpc52xx_spi_remove()
525 for (i = 0; i < ms->gpio_cs_count; i++) in mpc52xx_spi_remove()
526 gpiod_put(ms->gpio_cs[i]); in mpc52xx_spi_remove()
528 kfree(ms->gpio_cs); in mpc52xx_spi_remove()
530 iounmap(ms->regs); in mpc52xx_spi_remove()
537 { .compatible = "fsl,mpc5200-spi", },
544 .name = "mpc52xx-spi",