• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
4  * Copyright (C) 2013, Intel Corporation
5  */
6 
7 #include <linux/acpi.h>
8 #include <linux/bitops.h>
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/device.h>
12 #include <linux/err.h>
13 #include <linux/errno.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/gpio.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/ioport.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/mod_devicetable.h>
22 #include <linux/of.h>
23 #include <linux/pci.h>
24 #include <linux/platform_device.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/property.h>
27 #include <linux/slab.h>
28 #include <linux/spi/pxa2xx_spi.h>
29 #include <linux/spi/spi.h>
30 
31 #include "spi-pxa2xx.h"
32 
33 MODULE_AUTHOR("Stephen Street");
34 MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
35 MODULE_LICENSE("GPL");
36 MODULE_ALIAS("platform:pxa2xx-spi");
37 
38 #define TIMOUT_DFLT		1000
39 
40 /*
41  * for testing SSCR1 changes that require SSP restart, basically
42  * everything except the service and interrupt enables, the pxa270 developer
43  * manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
44  * list, but the PXA255 dev man says all bits without really meaning the
45  * service and interrupt enables
46  */
47 #define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
48 				| SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
49 				| SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
50 				| SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
51 				| SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
52 				| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
53 
54 #define QUARK_X1000_SSCR1_CHANGE_MASK (QUARK_X1000_SSCR1_STRF	\
55 				| QUARK_X1000_SSCR1_EFWR	\
56 				| QUARK_X1000_SSCR1_RFT		\
57 				| QUARK_X1000_SSCR1_TFT		\
58 				| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
59 
60 #define CE4100_SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
61 				| SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
62 				| SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
63 				| SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
64 				| CE4100_SSCR1_RFT | CE4100_SSCR1_TFT | SSCR1_MWDS \
65 				| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
66 
67 #define LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE	BIT(24)
68 #define LPSS_CS_CONTROL_SW_MODE			BIT(0)
69 #define LPSS_CS_CONTROL_CS_HIGH			BIT(1)
70 #define LPSS_CAPS_CS_EN_SHIFT			9
71 #define LPSS_CAPS_CS_EN_MASK			(0xf << LPSS_CAPS_CS_EN_SHIFT)
72 
73 #define LPSS_PRIV_CLOCK_GATE 0x38
74 #define LPSS_PRIV_CLOCK_GATE_CLK_CTL_MASK 0x3
75 #define LPSS_PRIV_CLOCK_GATE_CLK_CTL_FORCE_ON 0x3
76 
77 struct lpss_config {
78 	/* LPSS offset from drv_data->ioaddr */
79 	unsigned offset;
80 	/* Register offsets from drv_data->lpss_base or -1 */
81 	int reg_general;
82 	int reg_ssp;
83 	int reg_cs_ctrl;
84 	int reg_capabilities;
85 	/* FIFO thresholds */
86 	u32 rx_threshold;
87 	u32 tx_threshold_lo;
88 	u32 tx_threshold_hi;
89 	/* Chip select control */
90 	unsigned cs_sel_shift;
91 	unsigned cs_sel_mask;
92 	unsigned cs_num;
93 	/* Quirks */
94 	unsigned cs_clk_stays_gated : 1;
95 };
96 
97 /* Keep these sorted with enum pxa_ssp_type */
98 static const struct lpss_config lpss_platforms[] = {
99 	{	/* LPSS_LPT_SSP */
100 		.offset = 0x800,
101 		.reg_general = 0x08,
102 		.reg_ssp = 0x0c,
103 		.reg_cs_ctrl = 0x18,
104 		.reg_capabilities = -1,
105 		.rx_threshold = 64,
106 		.tx_threshold_lo = 160,
107 		.tx_threshold_hi = 224,
108 	},
109 	{	/* LPSS_BYT_SSP */
110 		.offset = 0x400,
111 		.reg_general = 0x08,
112 		.reg_ssp = 0x0c,
113 		.reg_cs_ctrl = 0x18,
114 		.reg_capabilities = -1,
115 		.rx_threshold = 64,
116 		.tx_threshold_lo = 160,
117 		.tx_threshold_hi = 224,
118 	},
119 	{	/* LPSS_BSW_SSP */
120 		.offset = 0x400,
121 		.reg_general = 0x08,
122 		.reg_ssp = 0x0c,
123 		.reg_cs_ctrl = 0x18,
124 		.reg_capabilities = -1,
125 		.rx_threshold = 64,
126 		.tx_threshold_lo = 160,
127 		.tx_threshold_hi = 224,
128 		.cs_sel_shift = 2,
129 		.cs_sel_mask = 1 << 2,
130 		.cs_num = 2,
131 	},
132 	{	/* LPSS_SPT_SSP */
133 		.offset = 0x200,
134 		.reg_general = -1,
135 		.reg_ssp = 0x20,
136 		.reg_cs_ctrl = 0x24,
137 		.reg_capabilities = -1,
138 		.rx_threshold = 1,
139 		.tx_threshold_lo = 32,
140 		.tx_threshold_hi = 56,
141 	},
142 	{	/* LPSS_BXT_SSP */
143 		.offset = 0x200,
144 		.reg_general = -1,
145 		.reg_ssp = 0x20,
146 		.reg_cs_ctrl = 0x24,
147 		.reg_capabilities = 0xfc,
148 		.rx_threshold = 1,
149 		.tx_threshold_lo = 16,
150 		.tx_threshold_hi = 48,
151 		.cs_sel_shift = 8,
152 		.cs_sel_mask = 3 << 8,
153 		.cs_clk_stays_gated = true,
154 	},
155 	{	/* LPSS_CNL_SSP */
156 		.offset = 0x200,
157 		.reg_general = -1,
158 		.reg_ssp = 0x20,
159 		.reg_cs_ctrl = 0x24,
160 		.reg_capabilities = 0xfc,
161 		.rx_threshold = 1,
162 		.tx_threshold_lo = 32,
163 		.tx_threshold_hi = 56,
164 		.cs_sel_shift = 8,
165 		.cs_sel_mask = 3 << 8,
166 		.cs_clk_stays_gated = true,
167 	},
168 };
169 
170 static inline const struct lpss_config
lpss_get_config(const struct driver_data * drv_data)171 *lpss_get_config(const struct driver_data *drv_data)
172 {
173 	return &lpss_platforms[drv_data->ssp_type - LPSS_LPT_SSP];
174 }
175 
is_lpss_ssp(const struct driver_data * drv_data)176 static bool is_lpss_ssp(const struct driver_data *drv_data)
177 {
178 	switch (drv_data->ssp_type) {
179 	case LPSS_LPT_SSP:
180 	case LPSS_BYT_SSP:
181 	case LPSS_BSW_SSP:
182 	case LPSS_SPT_SSP:
183 	case LPSS_BXT_SSP:
184 	case LPSS_CNL_SSP:
185 		return true;
186 	default:
187 		return false;
188 	}
189 }
190 
is_quark_x1000_ssp(const struct driver_data * drv_data)191 static bool is_quark_x1000_ssp(const struct driver_data *drv_data)
192 {
193 	return drv_data->ssp_type == QUARK_X1000_SSP;
194 }
195 
is_mmp2_ssp(const struct driver_data * drv_data)196 static bool is_mmp2_ssp(const struct driver_data *drv_data)
197 {
198 	return drv_data->ssp_type == MMP2_SSP;
199 }
200 
pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data * drv_data)201 static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data)
202 {
203 	switch (drv_data->ssp_type) {
204 	case QUARK_X1000_SSP:
205 		return QUARK_X1000_SSCR1_CHANGE_MASK;
206 	case CE4100_SSP:
207 		return CE4100_SSCR1_CHANGE_MASK;
208 	default:
209 		return SSCR1_CHANGE_MASK;
210 	}
211 }
212 
213 static u32
pxa2xx_spi_get_rx_default_thre(const struct driver_data * drv_data)214 pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data)
215 {
216 	switch (drv_data->ssp_type) {
217 	case QUARK_X1000_SSP:
218 		return RX_THRESH_QUARK_X1000_DFLT;
219 	case CE4100_SSP:
220 		return RX_THRESH_CE4100_DFLT;
221 	default:
222 		return RX_THRESH_DFLT;
223 	}
224 }
225 
pxa2xx_spi_txfifo_full(const struct driver_data * drv_data)226 static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data)
227 {
228 	u32 mask;
229 
230 	switch (drv_data->ssp_type) {
231 	case QUARK_X1000_SSP:
232 		mask = QUARK_X1000_SSSR_TFL_MASK;
233 		break;
234 	case CE4100_SSP:
235 		mask = CE4100_SSSR_TFL_MASK;
236 		break;
237 	default:
238 		mask = SSSR_TFL_MASK;
239 		break;
240 	}
241 
242 	return (pxa2xx_spi_read(drv_data, SSSR) & mask) == mask;
243 }
244 
pxa2xx_spi_clear_rx_thre(const struct driver_data * drv_data,u32 * sccr1_reg)245 static void pxa2xx_spi_clear_rx_thre(const struct driver_data *drv_data,
246 				     u32 *sccr1_reg)
247 {
248 	u32 mask;
249 
250 	switch (drv_data->ssp_type) {
251 	case QUARK_X1000_SSP:
252 		mask = QUARK_X1000_SSCR1_RFT;
253 		break;
254 	case CE4100_SSP:
255 		mask = CE4100_SSCR1_RFT;
256 		break;
257 	default:
258 		mask = SSCR1_RFT;
259 		break;
260 	}
261 	*sccr1_reg &= ~mask;
262 }
263 
pxa2xx_spi_set_rx_thre(const struct driver_data * drv_data,u32 * sccr1_reg,u32 threshold)264 static void pxa2xx_spi_set_rx_thre(const struct driver_data *drv_data,
265 				   u32 *sccr1_reg, u32 threshold)
266 {
267 	switch (drv_data->ssp_type) {
268 	case QUARK_X1000_SSP:
269 		*sccr1_reg |= QUARK_X1000_SSCR1_RxTresh(threshold);
270 		break;
271 	case CE4100_SSP:
272 		*sccr1_reg |= CE4100_SSCR1_RxTresh(threshold);
273 		break;
274 	default:
275 		*sccr1_reg |= SSCR1_RxTresh(threshold);
276 		break;
277 	}
278 }
279 
pxa2xx_configure_sscr0(const struct driver_data * drv_data,u32 clk_div,u8 bits)280 static u32 pxa2xx_configure_sscr0(const struct driver_data *drv_data,
281 				  u32 clk_div, u8 bits)
282 {
283 	switch (drv_data->ssp_type) {
284 	case QUARK_X1000_SSP:
285 		return clk_div
286 			| QUARK_X1000_SSCR0_Motorola
287 			| QUARK_X1000_SSCR0_DataSize(bits > 32 ? 8 : bits)
288 			| SSCR0_SSE;
289 	default:
290 		return clk_div
291 			| SSCR0_Motorola
292 			| SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
293 			| SSCR0_SSE
294 			| (bits > 16 ? SSCR0_EDSS : 0);
295 	}
296 }
297 
298 /*
299  * Read and write LPSS SSP private registers. Caller must first check that
300  * is_lpss_ssp() returns true before these can be called.
301  */
__lpss_ssp_read_priv(struct driver_data * drv_data,unsigned offset)302 static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
303 {
304 	WARN_ON(!drv_data->lpss_base);
305 	return readl(drv_data->lpss_base + offset);
306 }
307 
__lpss_ssp_write_priv(struct driver_data * drv_data,unsigned offset,u32 value)308 static void __lpss_ssp_write_priv(struct driver_data *drv_data,
309 				  unsigned offset, u32 value)
310 {
311 	WARN_ON(!drv_data->lpss_base);
312 	writel(value, drv_data->lpss_base + offset);
313 }
314 
315 /*
316  * lpss_ssp_setup - perform LPSS SSP specific setup
317  * @drv_data: pointer to the driver private data
318  *
319  * Perform LPSS SSP specific setup. This function must be called first if
320  * one is going to use LPSS SSP private registers.
321  */
lpss_ssp_setup(struct driver_data * drv_data)322 static void lpss_ssp_setup(struct driver_data *drv_data)
323 {
324 	const struct lpss_config *config;
325 	u32 value;
326 
327 	config = lpss_get_config(drv_data);
328 	drv_data->lpss_base = drv_data->ioaddr + config->offset;
329 
330 	/* Enable software chip select control */
331 	value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
332 	value &= ~(LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH);
333 	value |= LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH;
334 	__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
335 
336 	/* Enable multiblock DMA transfers */
337 	if (drv_data->controller_info->enable_dma) {
338 		__lpss_ssp_write_priv(drv_data, config->reg_ssp, 1);
339 
340 		if (config->reg_general >= 0) {
341 			value = __lpss_ssp_read_priv(drv_data,
342 						     config->reg_general);
343 			value |= LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE;
344 			__lpss_ssp_write_priv(drv_data,
345 					      config->reg_general, value);
346 		}
347 	}
348 }
349 
lpss_ssp_select_cs(struct spi_device * spi,const struct lpss_config * config)350 static void lpss_ssp_select_cs(struct spi_device *spi,
351 			       const struct lpss_config *config)
352 {
353 	struct driver_data *drv_data =
354 		spi_controller_get_devdata(spi->controller);
355 	u32 value, cs;
356 
357 	if (!config->cs_sel_mask)
358 		return;
359 
360 	value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
361 
362 	cs = spi->chip_select;
363 	cs <<= config->cs_sel_shift;
364 	if (cs != (value & config->cs_sel_mask)) {
365 		/*
366 		 * When switching another chip select output active the
367 		 * output must be selected first and wait 2 ssp_clk cycles
368 		 * before changing state to active. Otherwise a short
369 		 * glitch will occur on the previous chip select since
370 		 * output select is latched but state control is not.
371 		 */
372 		value &= ~config->cs_sel_mask;
373 		value |= cs;
374 		__lpss_ssp_write_priv(drv_data,
375 				      config->reg_cs_ctrl, value);
376 		ndelay(1000000000 /
377 		       (drv_data->controller->max_speed_hz / 2));
378 	}
379 }
380 
lpss_ssp_cs_control(struct spi_device * spi,bool enable)381 static void lpss_ssp_cs_control(struct spi_device *spi, bool enable)
382 {
383 	struct driver_data *drv_data =
384 		spi_controller_get_devdata(spi->controller);
385 	const struct lpss_config *config;
386 	u32 value;
387 
388 	config = lpss_get_config(drv_data);
389 
390 	if (enable)
391 		lpss_ssp_select_cs(spi, config);
392 
393 	value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
394 	if (enable)
395 		value &= ~LPSS_CS_CONTROL_CS_HIGH;
396 	else
397 		value |= LPSS_CS_CONTROL_CS_HIGH;
398 	__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
399 	if (config->cs_clk_stays_gated) {
400 		u32 clkgate;
401 
402 		/*
403 		 * Changing CS alone when dynamic clock gating is on won't
404 		 * actually flip CS at that time. This ruins SPI transfers
405 		 * that specify delays, or have no data. Toggle the clock mode
406 		 * to force on briefly to poke the CS pin to move.
407 		 */
408 		clkgate = __lpss_ssp_read_priv(drv_data, LPSS_PRIV_CLOCK_GATE);
409 		value = (clkgate & ~LPSS_PRIV_CLOCK_GATE_CLK_CTL_MASK) |
410 			LPSS_PRIV_CLOCK_GATE_CLK_CTL_FORCE_ON;
411 
412 		__lpss_ssp_write_priv(drv_data, LPSS_PRIV_CLOCK_GATE, value);
413 		__lpss_ssp_write_priv(drv_data, LPSS_PRIV_CLOCK_GATE, clkgate);
414 	}
415 }
416 
cs_assert(struct spi_device * spi)417 static void cs_assert(struct spi_device *spi)
418 {
419 	struct chip_data *chip = spi_get_ctldata(spi);
420 	struct driver_data *drv_data =
421 		spi_controller_get_devdata(spi->controller);
422 
423 	if (drv_data->ssp_type == CE4100_SSP) {
424 		pxa2xx_spi_write(drv_data, SSSR, chip->frm);
425 		return;
426 	}
427 
428 	if (chip->cs_control) {
429 		chip->cs_control(PXA2XX_CS_ASSERT);
430 		return;
431 	}
432 
433 	if (chip->gpiod_cs) {
434 		gpiod_set_value(chip->gpiod_cs, chip->gpio_cs_inverted);
435 		return;
436 	}
437 
438 	if (is_lpss_ssp(drv_data))
439 		lpss_ssp_cs_control(spi, true);
440 }
441 
cs_deassert(struct spi_device * spi)442 static void cs_deassert(struct spi_device *spi)
443 {
444 	struct chip_data *chip = spi_get_ctldata(spi);
445 	struct driver_data *drv_data =
446 		spi_controller_get_devdata(spi->controller);
447 	unsigned long timeout;
448 
449 	if (drv_data->ssp_type == CE4100_SSP)
450 		return;
451 
452 	/* Wait until SSP becomes idle before deasserting the CS */
453 	timeout = jiffies + msecs_to_jiffies(10);
454 	while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY &&
455 	       !time_after(jiffies, timeout))
456 		cpu_relax();
457 
458 	if (chip->cs_control) {
459 		chip->cs_control(PXA2XX_CS_DEASSERT);
460 		return;
461 	}
462 
463 	if (chip->gpiod_cs) {
464 		gpiod_set_value(chip->gpiod_cs, !chip->gpio_cs_inverted);
465 		return;
466 	}
467 
468 	if (is_lpss_ssp(drv_data))
469 		lpss_ssp_cs_control(spi, false);
470 }
471 
pxa2xx_spi_set_cs(struct spi_device * spi,bool level)472 static void pxa2xx_spi_set_cs(struct spi_device *spi, bool level)
473 {
474 	if (level)
475 		cs_deassert(spi);
476 	else
477 		cs_assert(spi);
478 }
479 
pxa2xx_spi_flush(struct driver_data * drv_data)480 int pxa2xx_spi_flush(struct driver_data *drv_data)
481 {
482 	unsigned long limit = loops_per_jiffy << 1;
483 
484 	do {
485 		while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
486 			pxa2xx_spi_read(drv_data, SSDR);
487 	} while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit);
488 	write_SSSR_CS(drv_data, SSSR_ROR);
489 
490 	return limit;
491 }
492 
pxa2xx_spi_off(struct driver_data * drv_data)493 static void pxa2xx_spi_off(struct driver_data *drv_data)
494 {
495 	/* On MMP, disabling SSE seems to corrupt the Rx FIFO */
496 	if (is_mmp2_ssp(drv_data))
497 		return;
498 
499 	pxa2xx_spi_write(drv_data, SSCR0,
500 			 pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
501 }
502 
null_writer(struct driver_data * drv_data)503 static int null_writer(struct driver_data *drv_data)
504 {
505 	u8 n_bytes = drv_data->n_bytes;
506 
507 	if (pxa2xx_spi_txfifo_full(drv_data)
508 		|| (drv_data->tx == drv_data->tx_end))
509 		return 0;
510 
511 	pxa2xx_spi_write(drv_data, SSDR, 0);
512 	drv_data->tx += n_bytes;
513 
514 	return 1;
515 }
516 
null_reader(struct driver_data * drv_data)517 static int null_reader(struct driver_data *drv_data)
518 {
519 	u8 n_bytes = drv_data->n_bytes;
520 
521 	while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
522 	       && (drv_data->rx < drv_data->rx_end)) {
523 		pxa2xx_spi_read(drv_data, SSDR);
524 		drv_data->rx += n_bytes;
525 	}
526 
527 	return drv_data->rx == drv_data->rx_end;
528 }
529 
u8_writer(struct driver_data * drv_data)530 static int u8_writer(struct driver_data *drv_data)
531 {
532 	if (pxa2xx_spi_txfifo_full(drv_data)
533 		|| (drv_data->tx == drv_data->tx_end))
534 		return 0;
535 
536 	pxa2xx_spi_write(drv_data, SSDR, *(u8 *)(drv_data->tx));
537 	++drv_data->tx;
538 
539 	return 1;
540 }
541 
u8_reader(struct driver_data * drv_data)542 static int u8_reader(struct driver_data *drv_data)
543 {
544 	while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
545 	       && (drv_data->rx < drv_data->rx_end)) {
546 		*(u8 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
547 		++drv_data->rx;
548 	}
549 
550 	return drv_data->rx == drv_data->rx_end;
551 }
552 
u16_writer(struct driver_data * drv_data)553 static int u16_writer(struct driver_data *drv_data)
554 {
555 	if (pxa2xx_spi_txfifo_full(drv_data)
556 		|| (drv_data->tx == drv_data->tx_end))
557 		return 0;
558 
559 	pxa2xx_spi_write(drv_data, SSDR, *(u16 *)(drv_data->tx));
560 	drv_data->tx += 2;
561 
562 	return 1;
563 }
564 
u16_reader(struct driver_data * drv_data)565 static int u16_reader(struct driver_data *drv_data)
566 {
567 	while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
568 	       && (drv_data->rx < drv_data->rx_end)) {
569 		*(u16 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
570 		drv_data->rx += 2;
571 	}
572 
573 	return drv_data->rx == drv_data->rx_end;
574 }
575 
u32_writer(struct driver_data * drv_data)576 static int u32_writer(struct driver_data *drv_data)
577 {
578 	if (pxa2xx_spi_txfifo_full(drv_data)
579 		|| (drv_data->tx == drv_data->tx_end))
580 		return 0;
581 
582 	pxa2xx_spi_write(drv_data, SSDR, *(u32 *)(drv_data->tx));
583 	drv_data->tx += 4;
584 
585 	return 1;
586 }
587 
u32_reader(struct driver_data * drv_data)588 static int u32_reader(struct driver_data *drv_data)
589 {
590 	while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
591 	       && (drv_data->rx < drv_data->rx_end)) {
592 		*(u32 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
593 		drv_data->rx += 4;
594 	}
595 
596 	return drv_data->rx == drv_data->rx_end;
597 }
598 
reset_sccr1(struct driver_data * drv_data)599 static void reset_sccr1(struct driver_data *drv_data)
600 {
601 	struct chip_data *chip =
602 		spi_get_ctldata(drv_data->controller->cur_msg->spi);
603 	u32 sccr1_reg;
604 
605 	sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1;
606 	switch (drv_data->ssp_type) {
607 	case QUARK_X1000_SSP:
608 		sccr1_reg &= ~QUARK_X1000_SSCR1_RFT;
609 		break;
610 	case CE4100_SSP:
611 		sccr1_reg &= ~CE4100_SSCR1_RFT;
612 		break;
613 	default:
614 		sccr1_reg &= ~SSCR1_RFT;
615 		break;
616 	}
617 	sccr1_reg |= chip->threshold;
618 	pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
619 }
620 
int_error_stop(struct driver_data * drv_data,const char * msg)621 static void int_error_stop(struct driver_data *drv_data, const char* msg)
622 {
623 	/* Stop and reset SSP */
624 	write_SSSR_CS(drv_data, drv_data->clear_sr);
625 	reset_sccr1(drv_data);
626 	if (!pxa25x_ssp_comp(drv_data))
627 		pxa2xx_spi_write(drv_data, SSTO, 0);
628 	pxa2xx_spi_flush(drv_data);
629 	pxa2xx_spi_off(drv_data);
630 
631 	dev_err(&drv_data->pdev->dev, "%s\n", msg);
632 
633 	drv_data->controller->cur_msg->status = -EIO;
634 	spi_finalize_current_transfer(drv_data->controller);
635 }
636 
int_transfer_complete(struct driver_data * drv_data)637 static void int_transfer_complete(struct driver_data *drv_data)
638 {
639 	/* Clear and disable interrupts */
640 	write_SSSR_CS(drv_data, drv_data->clear_sr);
641 	reset_sccr1(drv_data);
642 	if (!pxa25x_ssp_comp(drv_data))
643 		pxa2xx_spi_write(drv_data, SSTO, 0);
644 
645 	spi_finalize_current_transfer(drv_data->controller);
646 }
647 
interrupt_transfer(struct driver_data * drv_data)648 static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
649 {
650 	u32 irq_mask = (pxa2xx_spi_read(drv_data, SSCR1) & SSCR1_TIE) ?
651 		       drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
652 
653 	u32 irq_status = pxa2xx_spi_read(drv_data, SSSR) & irq_mask;
654 
655 	if (irq_status & SSSR_ROR) {
656 		int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
657 		return IRQ_HANDLED;
658 	}
659 
660 	if (irq_status & SSSR_TUR) {
661 		int_error_stop(drv_data, "interrupt_transfer: fifo underrun");
662 		return IRQ_HANDLED;
663 	}
664 
665 	if (irq_status & SSSR_TINT) {
666 		pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT);
667 		if (drv_data->read(drv_data)) {
668 			int_transfer_complete(drv_data);
669 			return IRQ_HANDLED;
670 		}
671 	}
672 
673 	/* Drain rx fifo, Fill tx fifo and prevent overruns */
674 	do {
675 		if (drv_data->read(drv_data)) {
676 			int_transfer_complete(drv_data);
677 			return IRQ_HANDLED;
678 		}
679 	} while (drv_data->write(drv_data));
680 
681 	if (drv_data->read(drv_data)) {
682 		int_transfer_complete(drv_data);
683 		return IRQ_HANDLED;
684 	}
685 
686 	if (drv_data->tx == drv_data->tx_end) {
687 		u32 bytes_left;
688 		u32 sccr1_reg;
689 
690 		sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
691 		sccr1_reg &= ~SSCR1_TIE;
692 
693 		/*
694 		 * PXA25x_SSP has no timeout, set up rx threshould for the
695 		 * remaining RX bytes.
696 		 */
697 		if (pxa25x_ssp_comp(drv_data)) {
698 			u32 rx_thre;
699 
700 			pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg);
701 
702 			bytes_left = drv_data->rx_end - drv_data->rx;
703 			switch (drv_data->n_bytes) {
704 			case 4:
705 				bytes_left >>= 2;
706 				break;
707 			case 2:
708 				bytes_left >>= 1;
709 				break;
710 			}
711 
712 			rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data);
713 			if (rx_thre > bytes_left)
714 				rx_thre = bytes_left;
715 
716 			pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre);
717 		}
718 		pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
719 	}
720 
721 	/* We did something */
722 	return IRQ_HANDLED;
723 }
724 
handle_bad_msg(struct driver_data * drv_data)725 static void handle_bad_msg(struct driver_data *drv_data)
726 {
727 	pxa2xx_spi_off(drv_data);
728 	pxa2xx_spi_write(drv_data, SSCR1,
729 			 pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1);
730 	if (!pxa25x_ssp_comp(drv_data))
731 		pxa2xx_spi_write(drv_data, SSTO, 0);
732 	write_SSSR_CS(drv_data, drv_data->clear_sr);
733 
734 	dev_err(&drv_data->pdev->dev,
735 		"bad message state in interrupt handler\n");
736 }
737 
ssp_int(int irq,void * dev_id)738 static irqreturn_t ssp_int(int irq, void *dev_id)
739 {
740 	struct driver_data *drv_data = dev_id;
741 	u32 sccr1_reg;
742 	u32 mask = drv_data->mask_sr;
743 	u32 status;
744 
745 	/*
746 	 * The IRQ might be shared with other peripherals so we must first
747 	 * check that are we RPM suspended or not. If we are we assume that
748 	 * the IRQ was not for us (we shouldn't be RPM suspended when the
749 	 * interrupt is enabled).
750 	 */
751 	if (pm_runtime_suspended(&drv_data->pdev->dev))
752 		return IRQ_NONE;
753 
754 	/*
755 	 * If the device is not yet in RPM suspended state and we get an
756 	 * interrupt that is meant for another device, check if status bits
757 	 * are all set to one. That means that the device is already
758 	 * powered off.
759 	 */
760 	status = pxa2xx_spi_read(drv_data, SSSR);
761 	if (status == ~0)
762 		return IRQ_NONE;
763 
764 	sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
765 
766 	/* Ignore possible writes if we don't need to write */
767 	if (!(sccr1_reg & SSCR1_TIE))
768 		mask &= ~SSSR_TFS;
769 
770 	/* Ignore RX timeout interrupt if it is disabled */
771 	if (!(sccr1_reg & SSCR1_TINTE))
772 		mask &= ~SSSR_TINT;
773 
774 	if (!(status & mask))
775 		return IRQ_NONE;
776 
777 	pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg & ~drv_data->int_cr1);
778 	pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
779 
780 	if (!drv_data->controller->cur_msg) {
781 		handle_bad_msg(drv_data);
782 		/* Never fail */
783 		return IRQ_HANDLED;
784 	}
785 
786 	return drv_data->transfer_handler(drv_data);
787 }
788 
789 /*
790  * The Quark SPI has an additional 24 bit register (DDS_CLK_RATE) to multiply
791  * input frequency by fractions of 2^24. It also has a divider by 5.
792  *
793  * There are formulas to get baud rate value for given input frequency and
794  * divider parameters, such as DDS_CLK_RATE and SCR:
795  *
796  * Fsys = 200MHz
797  *
798  * Fssp = Fsys * DDS_CLK_RATE / 2^24			(1)
799  * Baud rate = Fsclk = Fssp / (2 * (SCR + 1))		(2)
800  *
801  * DDS_CLK_RATE either 2^n or 2^n / 5.
802  * SCR is in range 0 .. 255
803  *
804  * Divisor = 5^i * 2^j * 2 * k
805  *       i = [0, 1]      i = 1 iff j = 0 or j > 3
806  *       j = [0, 23]     j = 0 iff i = 1
807  *       k = [1, 256]
808  * Special case: j = 0, i = 1: Divisor = 2 / 5
809  *
810  * Accordingly to the specification the recommended values for DDS_CLK_RATE
811  * are:
812  *	Case 1:		2^n, n = [0, 23]
813  *	Case 2:		2^24 * 2 / 5 (0x666666)
814  *	Case 3:		less than or equal to 2^24 / 5 / 16 (0x33333)
815  *
816  * In all cases the lowest possible value is better.
817  *
818  * The function calculates parameters for all cases and chooses the one closest
819  * to the asked baud rate.
820  */
quark_x1000_get_clk_div(int rate,u32 * dds)821 static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
822 {
823 	unsigned long xtal = 200000000;
824 	unsigned long fref = xtal / 2;		/* mandatory division by 2,
825 						   see (2) */
826 						/* case 3 */
827 	unsigned long fref1 = fref / 2;		/* case 1 */
828 	unsigned long fref2 = fref * 2 / 5;	/* case 2 */
829 	unsigned long scale;
830 	unsigned long q, q1, q2;
831 	long r, r1, r2;
832 	u32 mul;
833 
834 	/* Case 1 */
835 
836 	/* Set initial value for DDS_CLK_RATE */
837 	mul = (1 << 24) >> 1;
838 
839 	/* Calculate initial quot */
840 	q1 = DIV_ROUND_UP(fref1, rate);
841 
842 	/* Scale q1 if it's too big */
843 	if (q1 > 256) {
844 		/* Scale q1 to range [1, 512] */
845 		scale = fls_long(q1 - 1);
846 		if (scale > 9) {
847 			q1 >>= scale - 9;
848 			mul >>= scale - 9;
849 		}
850 
851 		/* Round the result if we have a remainder */
852 		q1 += q1 & 1;
853 	}
854 
855 	/* Decrease DDS_CLK_RATE as much as we can without loss in precision */
856 	scale = __ffs(q1);
857 	q1 >>= scale;
858 	mul >>= scale;
859 
860 	/* Get the remainder */
861 	r1 = abs(fref1 / (1 << (24 - fls_long(mul))) / q1 - rate);
862 
863 	/* Case 2 */
864 
865 	q2 = DIV_ROUND_UP(fref2, rate);
866 	r2 = abs(fref2 / q2 - rate);
867 
868 	/*
869 	 * Choose the best between two: less remainder we have the better. We
870 	 * can't go case 2 if q2 is greater than 256 since SCR register can
871 	 * hold only values 0 .. 255.
872 	 */
873 	if (r2 >= r1 || q2 > 256) {
874 		/* case 1 is better */
875 		r = r1;
876 		q = q1;
877 	} else {
878 		/* case 2 is better */
879 		r = r2;
880 		q = q2;
881 		mul = (1 << 24) * 2 / 5;
882 	}
883 
884 	/* Check case 3 only if the divisor is big enough */
885 	if (fref / rate >= 80) {
886 		u64 fssp;
887 		u32 m;
888 
889 		/* Calculate initial quot */
890 		q1 = DIV_ROUND_UP(fref, rate);
891 		m = (1 << 24) / q1;
892 
893 		/* Get the remainder */
894 		fssp = (u64)fref * m;
895 		do_div(fssp, 1 << 24);
896 		r1 = abs(fssp - rate);
897 
898 		/* Choose this one if it suits better */
899 		if (r1 < r) {
900 			/* case 3 is better */
901 			q = 1;
902 			mul = m;
903 		}
904 	}
905 
906 	*dds = mul;
907 	return q - 1;
908 }
909 
ssp_get_clk_div(struct driver_data * drv_data,int rate)910 static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
911 {
912 	unsigned long ssp_clk = drv_data->controller->max_speed_hz;
913 	const struct ssp_device *ssp = drv_data->ssp;
914 
915 	rate = min_t(int, ssp_clk, rate);
916 
917 	/*
918 	 * Calculate the divisor for the SCR (Serial Clock Rate), avoiding
919 	 * that the SSP transmission rate can be greater than the device rate
920 	 */
921 	if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
922 		return (DIV_ROUND_UP(ssp_clk, 2 * rate) - 1) & 0xff;
923 	else
924 		return (DIV_ROUND_UP(ssp_clk, rate) - 1)  & 0xfff;
925 }
926 
pxa2xx_ssp_get_clk_div(struct driver_data * drv_data,int rate)927 static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data,
928 					   int rate)
929 {
930 	struct chip_data *chip =
931 		spi_get_ctldata(drv_data->controller->cur_msg->spi);
932 	unsigned int clk_div;
933 
934 	switch (drv_data->ssp_type) {
935 	case QUARK_X1000_SSP:
936 		clk_div = quark_x1000_get_clk_div(rate, &chip->dds_rate);
937 		break;
938 	default:
939 		clk_div = ssp_get_clk_div(drv_data, rate);
940 		break;
941 	}
942 	return clk_div << 8;
943 }
944 
pxa2xx_spi_can_dma(struct spi_controller * controller,struct spi_device * spi,struct spi_transfer * xfer)945 static bool pxa2xx_spi_can_dma(struct spi_controller *controller,
946 			       struct spi_device *spi,
947 			       struct spi_transfer *xfer)
948 {
949 	struct chip_data *chip = spi_get_ctldata(spi);
950 
951 	return chip->enable_dma &&
952 	       xfer->len <= MAX_DMA_LEN &&
953 	       xfer->len >= chip->dma_burst_size;
954 }
955 
pxa2xx_spi_transfer_one(struct spi_controller * controller,struct spi_device * spi,struct spi_transfer * transfer)956 static int pxa2xx_spi_transfer_one(struct spi_controller *controller,
957 				   struct spi_device *spi,
958 				   struct spi_transfer *transfer)
959 {
960 	struct driver_data *drv_data = spi_controller_get_devdata(controller);
961 	struct spi_message *message = controller->cur_msg;
962 	struct chip_data *chip = spi_get_ctldata(spi);
963 	u32 dma_thresh = chip->dma_threshold;
964 	u32 dma_burst = chip->dma_burst_size;
965 	u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data);
966 	u32 clk_div;
967 	u8 bits;
968 	u32 speed;
969 	u32 cr0;
970 	u32 cr1;
971 	int err;
972 	int dma_mapped;
973 
974 	/* Check if we can DMA this transfer */
975 	if (transfer->len > MAX_DMA_LEN && chip->enable_dma) {
976 
977 		/* reject already-mapped transfers; PIO won't always work */
978 		if (message->is_dma_mapped
979 				|| transfer->rx_dma || transfer->tx_dma) {
980 			dev_err(&spi->dev,
981 				"Mapped transfer length of %u is greater than %d\n",
982 				transfer->len, MAX_DMA_LEN);
983 			return -EINVAL;
984 		}
985 
986 		/* warn ... we force this to PIO mode */
987 		dev_warn_ratelimited(&spi->dev,
988 				     "DMA disabled for transfer length %ld greater than %d\n",
989 				     (long)transfer->len, MAX_DMA_LEN);
990 	}
991 
992 	/* Setup the transfer state based on the type of transfer */
993 	if (pxa2xx_spi_flush(drv_data) == 0) {
994 		dev_err(&spi->dev, "Flush failed\n");
995 		return -EIO;
996 	}
997 	drv_data->n_bytes = chip->n_bytes;
998 	drv_data->tx = (void *)transfer->tx_buf;
999 	drv_data->tx_end = drv_data->tx + transfer->len;
1000 	drv_data->rx = transfer->rx_buf;
1001 	drv_data->rx_end = drv_data->rx + transfer->len;
1002 	drv_data->write = drv_data->tx ? chip->write : null_writer;
1003 	drv_data->read = drv_data->rx ? chip->read : null_reader;
1004 
1005 	/* Change speed and bit per word on a per transfer */
1006 	bits = transfer->bits_per_word;
1007 	speed = transfer->speed_hz;
1008 
1009 	clk_div = pxa2xx_ssp_get_clk_div(drv_data, speed);
1010 
1011 	if (bits <= 8) {
1012 		drv_data->n_bytes = 1;
1013 		drv_data->read = drv_data->read != null_reader ?
1014 					u8_reader : null_reader;
1015 		drv_data->write = drv_data->write != null_writer ?
1016 					u8_writer : null_writer;
1017 	} else if (bits <= 16) {
1018 		drv_data->n_bytes = 2;
1019 		drv_data->read = drv_data->read != null_reader ?
1020 					u16_reader : null_reader;
1021 		drv_data->write = drv_data->write != null_writer ?
1022 					u16_writer : null_writer;
1023 	} else if (bits <= 32) {
1024 		drv_data->n_bytes = 4;
1025 		drv_data->read = drv_data->read != null_reader ?
1026 					u32_reader : null_reader;
1027 		drv_data->write = drv_data->write != null_writer ?
1028 					u32_writer : null_writer;
1029 	}
1030 	/*
1031 	 * if bits/word is changed in dma mode, then must check the
1032 	 * thresholds and burst also
1033 	 */
1034 	if (chip->enable_dma) {
1035 		if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
1036 						spi,
1037 						bits, &dma_burst,
1038 						&dma_thresh))
1039 			dev_warn_ratelimited(&spi->dev,
1040 					     "DMA burst size reduced to match bits_per_word\n");
1041 	}
1042 
1043 	dma_mapped = controller->can_dma &&
1044 		     controller->can_dma(controller, spi, transfer) &&
1045 		     controller->cur_msg_mapped;
1046 	if (dma_mapped) {
1047 
1048 		/* Ensure we have the correct interrupt handler */
1049 		drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
1050 
1051 		err = pxa2xx_spi_dma_prepare(drv_data, transfer);
1052 		if (err)
1053 			return err;
1054 
1055 		/* Clear status and start DMA engine */
1056 		cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
1057 		pxa2xx_spi_write(drv_data, SSSR, drv_data->clear_sr);
1058 
1059 		pxa2xx_spi_dma_start(drv_data);
1060 	} else {
1061 		/* Ensure we have the correct interrupt handler	*/
1062 		drv_data->transfer_handler = interrupt_transfer;
1063 
1064 		/* Clear status  */
1065 		cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
1066 		write_SSSR_CS(drv_data, drv_data->clear_sr);
1067 	}
1068 
1069 	/* NOTE:  PXA25x_SSP _could_ use external clocking ... */
1070 	cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits);
1071 	if (!pxa25x_ssp_comp(drv_data))
1072 		dev_dbg(&spi->dev, "%u Hz actual, %s\n",
1073 			controller->max_speed_hz
1074 				/ (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
1075 			dma_mapped ? "DMA" : "PIO");
1076 	else
1077 		dev_dbg(&spi->dev, "%u Hz actual, %s\n",
1078 			controller->max_speed_hz / 2
1079 				/ (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
1080 			dma_mapped ? "DMA" : "PIO");
1081 
1082 	if (is_lpss_ssp(drv_data)) {
1083 		if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff)
1084 		    != chip->lpss_rx_threshold)
1085 			pxa2xx_spi_write(drv_data, SSIRF,
1086 					 chip->lpss_rx_threshold);
1087 		if ((pxa2xx_spi_read(drv_data, SSITF) & 0xffff)
1088 		    != chip->lpss_tx_threshold)
1089 			pxa2xx_spi_write(drv_data, SSITF,
1090 					 chip->lpss_tx_threshold);
1091 	}
1092 
1093 	if (is_quark_x1000_ssp(drv_data) &&
1094 	    (pxa2xx_spi_read(drv_data, DDS_RATE) != chip->dds_rate))
1095 		pxa2xx_spi_write(drv_data, DDS_RATE, chip->dds_rate);
1096 
1097 	/* see if we need to reload the config registers */
1098 	if ((pxa2xx_spi_read(drv_data, SSCR0) != cr0)
1099 	    || (pxa2xx_spi_read(drv_data, SSCR1) & change_mask)
1100 	    != (cr1 & change_mask)) {
1101 		/* stop the SSP, and update the other bits */
1102 		if (!is_mmp2_ssp(drv_data))
1103 			pxa2xx_spi_write(drv_data, SSCR0, cr0 & ~SSCR0_SSE);
1104 		if (!pxa25x_ssp_comp(drv_data))
1105 			pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
1106 		/* first set CR1 without interrupt and service enables */
1107 		pxa2xx_spi_write(drv_data, SSCR1, cr1 & change_mask);
1108 		/* restart the SSP */
1109 		pxa2xx_spi_write(drv_data, SSCR0, cr0);
1110 
1111 	} else {
1112 		if (!pxa25x_ssp_comp(drv_data))
1113 			pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
1114 	}
1115 
1116 	if (is_mmp2_ssp(drv_data)) {
1117 		u8 tx_level = (pxa2xx_spi_read(drv_data, SSSR)
1118 					& SSSR_TFL_MASK) >> 8;
1119 
1120 		if (tx_level) {
1121 			/* On MMP2, flipping SSE doesn't to empty TXFIFO. */
1122 			dev_warn(&spi->dev, "%d bytes of garbage in TXFIFO!\n",
1123 								tx_level);
1124 			if (tx_level > transfer->len)
1125 				tx_level = transfer->len;
1126 			drv_data->tx += tx_level;
1127 		}
1128 	}
1129 
1130 	if (spi_controller_is_slave(controller)) {
1131 		while (drv_data->write(drv_data))
1132 			;
1133 		if (drv_data->gpiod_ready) {
1134 			gpiod_set_value(drv_data->gpiod_ready, 1);
1135 			udelay(1);
1136 			gpiod_set_value(drv_data->gpiod_ready, 0);
1137 		}
1138 	}
1139 
1140 	/*
1141 	 * Release the data by enabling service requests and interrupts,
1142 	 * without changing any mode bits
1143 	 */
1144 	pxa2xx_spi_write(drv_data, SSCR1, cr1);
1145 
1146 	return 1;
1147 }
1148 
pxa2xx_spi_slave_abort(struct spi_controller * controller)1149 static int pxa2xx_spi_slave_abort(struct spi_controller *controller)
1150 {
1151 	struct driver_data *drv_data = spi_controller_get_devdata(controller);
1152 
1153 	/* Stop and reset SSP */
1154 	write_SSSR_CS(drv_data, drv_data->clear_sr);
1155 	reset_sccr1(drv_data);
1156 	if (!pxa25x_ssp_comp(drv_data))
1157 		pxa2xx_spi_write(drv_data, SSTO, 0);
1158 	pxa2xx_spi_flush(drv_data);
1159 	pxa2xx_spi_off(drv_data);
1160 
1161 	dev_dbg(&drv_data->pdev->dev, "transfer aborted\n");
1162 
1163 	drv_data->controller->cur_msg->status = -EINTR;
1164 	spi_finalize_current_transfer(drv_data->controller);
1165 
1166 	return 0;
1167 }
1168 
pxa2xx_spi_handle_err(struct spi_controller * controller,struct spi_message * msg)1169 static void pxa2xx_spi_handle_err(struct spi_controller *controller,
1170 				 struct spi_message *msg)
1171 {
1172 	struct driver_data *drv_data = spi_controller_get_devdata(controller);
1173 
1174 	/* Disable the SSP */
1175 	pxa2xx_spi_off(drv_data);
1176 	/* Clear and disable interrupts and service requests */
1177 	write_SSSR_CS(drv_data, drv_data->clear_sr);
1178 	pxa2xx_spi_write(drv_data, SSCR1,
1179 			 pxa2xx_spi_read(drv_data, SSCR1)
1180 			 & ~(drv_data->int_cr1 | drv_data->dma_cr1));
1181 	if (!pxa25x_ssp_comp(drv_data))
1182 		pxa2xx_spi_write(drv_data, SSTO, 0);
1183 
1184 	/*
1185 	 * Stop the DMA if running. Note DMA callback handler may have unset
1186 	 * the dma_running already, which is fine as stopping is not needed
1187 	 * then but we shouldn't rely this flag for anything else than
1188 	 * stopping. For instance to differentiate between PIO and DMA
1189 	 * transfers.
1190 	 */
1191 	if (atomic_read(&drv_data->dma_running))
1192 		pxa2xx_spi_dma_stop(drv_data);
1193 }
1194 
pxa2xx_spi_unprepare_transfer(struct spi_controller * controller)1195 static int pxa2xx_spi_unprepare_transfer(struct spi_controller *controller)
1196 {
1197 	struct driver_data *drv_data = spi_controller_get_devdata(controller);
1198 
1199 	/* Disable the SSP now */
1200 	pxa2xx_spi_off(drv_data);
1201 
1202 	return 0;
1203 }
1204 
setup_cs(struct spi_device * spi,struct chip_data * chip,struct pxa2xx_spi_chip * chip_info)1205 static int setup_cs(struct spi_device *spi, struct chip_data *chip,
1206 		    struct pxa2xx_spi_chip *chip_info)
1207 {
1208 	struct driver_data *drv_data =
1209 		spi_controller_get_devdata(spi->controller);
1210 	struct gpio_desc *gpiod;
1211 	int err = 0;
1212 
1213 	if (chip == NULL)
1214 		return 0;
1215 
1216 	if (drv_data->cs_gpiods) {
1217 		gpiod = drv_data->cs_gpiods[spi->chip_select];
1218 		if (gpiod) {
1219 			chip->gpiod_cs = gpiod;
1220 			chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
1221 			gpiod_set_value(gpiod, chip->gpio_cs_inverted);
1222 		}
1223 
1224 		return 0;
1225 	}
1226 
1227 	if (chip_info == NULL)
1228 		return 0;
1229 
1230 	/* NOTE: setup() can be called multiple times, possibly with
1231 	 * different chip_info, release previously requested GPIO
1232 	 */
1233 	if (chip->gpiod_cs) {
1234 		gpiod_put(chip->gpiod_cs);
1235 		chip->gpiod_cs = NULL;
1236 	}
1237 
1238 	/* If (*cs_control) is provided, ignore GPIO chip select */
1239 	if (chip_info->cs_control) {
1240 		chip->cs_control = chip_info->cs_control;
1241 		return 0;
1242 	}
1243 
1244 	if (gpio_is_valid(chip_info->gpio_cs)) {
1245 		err = gpio_request(chip_info->gpio_cs, "SPI_CS");
1246 		if (err) {
1247 			dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
1248 				chip_info->gpio_cs);
1249 			return err;
1250 		}
1251 
1252 		gpiod = gpio_to_desc(chip_info->gpio_cs);
1253 		chip->gpiod_cs = gpiod;
1254 		chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
1255 
1256 		err = gpiod_direction_output(gpiod, !chip->gpio_cs_inverted);
1257 		if (err)
1258 			gpiod_put(chip->gpiod_cs);
1259 	}
1260 
1261 	return err;
1262 }
1263 
setup(struct spi_device * spi)1264 static int setup(struct spi_device *spi)
1265 {
1266 	struct pxa2xx_spi_chip *chip_info;
1267 	struct chip_data *chip;
1268 	const struct lpss_config *config;
1269 	struct driver_data *drv_data =
1270 		spi_controller_get_devdata(spi->controller);
1271 	uint tx_thres, tx_hi_thres, rx_thres;
1272 	int err;
1273 
1274 	switch (drv_data->ssp_type) {
1275 	case QUARK_X1000_SSP:
1276 		tx_thres = TX_THRESH_QUARK_X1000_DFLT;
1277 		tx_hi_thres = 0;
1278 		rx_thres = RX_THRESH_QUARK_X1000_DFLT;
1279 		break;
1280 	case CE4100_SSP:
1281 		tx_thres = TX_THRESH_CE4100_DFLT;
1282 		tx_hi_thres = 0;
1283 		rx_thres = RX_THRESH_CE4100_DFLT;
1284 		break;
1285 	case LPSS_LPT_SSP:
1286 	case LPSS_BYT_SSP:
1287 	case LPSS_BSW_SSP:
1288 	case LPSS_SPT_SSP:
1289 	case LPSS_BXT_SSP:
1290 	case LPSS_CNL_SSP:
1291 		config = lpss_get_config(drv_data);
1292 		tx_thres = config->tx_threshold_lo;
1293 		tx_hi_thres = config->tx_threshold_hi;
1294 		rx_thres = config->rx_threshold;
1295 		break;
1296 	default:
1297 		tx_hi_thres = 0;
1298 		if (spi_controller_is_slave(drv_data->controller)) {
1299 			tx_thres = 1;
1300 			rx_thres = 2;
1301 		} else {
1302 			tx_thres = TX_THRESH_DFLT;
1303 			rx_thres = RX_THRESH_DFLT;
1304 		}
1305 		break;
1306 	}
1307 
1308 	/* Only alloc on first setup */
1309 	chip = spi_get_ctldata(spi);
1310 	if (!chip) {
1311 		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1312 		if (!chip)
1313 			return -ENOMEM;
1314 
1315 		if (drv_data->ssp_type == CE4100_SSP) {
1316 			if (spi->chip_select > 4) {
1317 				dev_err(&spi->dev,
1318 					"failed setup: cs number must not be > 4.\n");
1319 				kfree(chip);
1320 				return -EINVAL;
1321 			}
1322 
1323 			chip->frm = spi->chip_select;
1324 		}
1325 		chip->enable_dma = drv_data->controller_info->enable_dma;
1326 		chip->timeout = TIMOUT_DFLT;
1327 	}
1328 
1329 	/* protocol drivers may change the chip settings, so...
1330 	 * if chip_info exists, use it */
1331 	chip_info = spi->controller_data;
1332 
1333 	/* chip_info isn't always needed */
1334 	chip->cr1 = 0;
1335 	if (chip_info) {
1336 		if (chip_info->timeout)
1337 			chip->timeout = chip_info->timeout;
1338 		if (chip_info->tx_threshold)
1339 			tx_thres = chip_info->tx_threshold;
1340 		if (chip_info->tx_hi_threshold)
1341 			tx_hi_thres = chip_info->tx_hi_threshold;
1342 		if (chip_info->rx_threshold)
1343 			rx_thres = chip_info->rx_threshold;
1344 		chip->dma_threshold = 0;
1345 		if (chip_info->enable_loopback)
1346 			chip->cr1 = SSCR1_LBM;
1347 	}
1348 	if (spi_controller_is_slave(drv_data->controller)) {
1349 		chip->cr1 |= SSCR1_SCFR;
1350 		chip->cr1 |= SSCR1_SCLKDIR;
1351 		chip->cr1 |= SSCR1_SFRMDIR;
1352 		chip->cr1 |= SSCR1_SPH;
1353 	}
1354 
1355 	chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
1356 	chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
1357 				| SSITF_TxHiThresh(tx_hi_thres);
1358 
1359 	/* set dma burst and threshold outside of chip_info path so that if
1360 	 * chip_info goes away after setting chip->enable_dma, the
1361 	 * burst and threshold can still respond to changes in bits_per_word */
1362 	if (chip->enable_dma) {
1363 		/* set up legal burst and threshold for dma */
1364 		if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
1365 						spi->bits_per_word,
1366 						&chip->dma_burst_size,
1367 						&chip->dma_threshold)) {
1368 			dev_warn(&spi->dev,
1369 				 "in setup: DMA burst size reduced to match bits_per_word\n");
1370 		}
1371 		dev_dbg(&spi->dev,
1372 			"in setup: DMA burst size set to %u\n",
1373 			chip->dma_burst_size);
1374 	}
1375 
1376 	switch (drv_data->ssp_type) {
1377 	case QUARK_X1000_SSP:
1378 		chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres)
1379 				   & QUARK_X1000_SSCR1_RFT)
1380 				   | (QUARK_X1000_SSCR1_TxTresh(tx_thres)
1381 				   & QUARK_X1000_SSCR1_TFT);
1382 		break;
1383 	case CE4100_SSP:
1384 		chip->threshold = (CE4100_SSCR1_RxTresh(rx_thres) & CE4100_SSCR1_RFT) |
1385 			(CE4100_SSCR1_TxTresh(tx_thres) & CE4100_SSCR1_TFT);
1386 		break;
1387 	default:
1388 		chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
1389 			(SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
1390 		break;
1391 	}
1392 
1393 	chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
1394 	chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
1395 			| (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
1396 
1397 	if (spi->mode & SPI_LOOP)
1398 		chip->cr1 |= SSCR1_LBM;
1399 
1400 	if (spi->bits_per_word <= 8) {
1401 		chip->n_bytes = 1;
1402 		chip->read = u8_reader;
1403 		chip->write = u8_writer;
1404 	} else if (spi->bits_per_word <= 16) {
1405 		chip->n_bytes = 2;
1406 		chip->read = u16_reader;
1407 		chip->write = u16_writer;
1408 	} else if (spi->bits_per_word <= 32) {
1409 		chip->n_bytes = 4;
1410 		chip->read = u32_reader;
1411 		chip->write = u32_writer;
1412 	}
1413 
1414 	spi_set_ctldata(spi, chip);
1415 
1416 	if (drv_data->ssp_type == CE4100_SSP)
1417 		return 0;
1418 
1419 	err = setup_cs(spi, chip, chip_info);
1420 	if (err)
1421 		kfree(chip);
1422 
1423 	return err;
1424 }
1425 
cleanup(struct spi_device * spi)1426 static void cleanup(struct spi_device *spi)
1427 {
1428 	struct chip_data *chip = spi_get_ctldata(spi);
1429 	struct driver_data *drv_data =
1430 		spi_controller_get_devdata(spi->controller);
1431 
1432 	if (!chip)
1433 		return;
1434 
1435 	if (drv_data->ssp_type != CE4100_SSP && !drv_data->cs_gpiods &&
1436 	    chip->gpiod_cs)
1437 		gpiod_put(chip->gpiod_cs);
1438 
1439 	kfree(chip);
1440 }
1441 
1442 #ifdef CONFIG_ACPI
1443 static const struct acpi_device_id pxa2xx_spi_acpi_match[] = {
1444 	{ "INT33C0", LPSS_LPT_SSP },
1445 	{ "INT33C1", LPSS_LPT_SSP },
1446 	{ "INT3430", LPSS_LPT_SSP },
1447 	{ "INT3431", LPSS_LPT_SSP },
1448 	{ "80860F0E", LPSS_BYT_SSP },
1449 	{ "8086228E", LPSS_BSW_SSP },
1450 	{ },
1451 };
1452 MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
1453 #endif
1454 
1455 /*
1456  * PCI IDs of compound devices that integrate both host controller and private
1457  * integrated DMA engine. Please note these are not used in module
1458  * autoloading and probing in this module but matching the LPSS SSP type.
1459  */
1460 static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = {
1461 	/* SPT-LP */
1462 	{ PCI_VDEVICE(INTEL, 0x9d29), LPSS_SPT_SSP },
1463 	{ PCI_VDEVICE(INTEL, 0x9d2a), LPSS_SPT_SSP },
1464 	/* SPT-H */
1465 	{ PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP },
1466 	{ PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP },
1467 	/* KBL-H */
1468 	{ PCI_VDEVICE(INTEL, 0xa2a9), LPSS_SPT_SSP },
1469 	{ PCI_VDEVICE(INTEL, 0xa2aa), LPSS_SPT_SSP },
1470 	/* CML-V */
1471 	{ PCI_VDEVICE(INTEL, 0xa3a9), LPSS_SPT_SSP },
1472 	{ PCI_VDEVICE(INTEL, 0xa3aa), LPSS_SPT_SSP },
1473 	/* BXT A-Step */
1474 	{ PCI_VDEVICE(INTEL, 0x0ac2), LPSS_BXT_SSP },
1475 	{ PCI_VDEVICE(INTEL, 0x0ac4), LPSS_BXT_SSP },
1476 	{ PCI_VDEVICE(INTEL, 0x0ac6), LPSS_BXT_SSP },
1477 	/* BXT B-Step */
1478 	{ PCI_VDEVICE(INTEL, 0x1ac2), LPSS_BXT_SSP },
1479 	{ PCI_VDEVICE(INTEL, 0x1ac4), LPSS_BXT_SSP },
1480 	{ PCI_VDEVICE(INTEL, 0x1ac6), LPSS_BXT_SSP },
1481 	/* GLK */
1482 	{ PCI_VDEVICE(INTEL, 0x31c2), LPSS_BXT_SSP },
1483 	{ PCI_VDEVICE(INTEL, 0x31c4), LPSS_BXT_SSP },
1484 	{ PCI_VDEVICE(INTEL, 0x31c6), LPSS_BXT_SSP },
1485 	/* ICL-LP */
1486 	{ PCI_VDEVICE(INTEL, 0x34aa), LPSS_CNL_SSP },
1487 	{ PCI_VDEVICE(INTEL, 0x34ab), LPSS_CNL_SSP },
1488 	{ PCI_VDEVICE(INTEL, 0x34fb), LPSS_CNL_SSP },
1489 	/* EHL */
1490 	{ PCI_VDEVICE(INTEL, 0x4b2a), LPSS_BXT_SSP },
1491 	{ PCI_VDEVICE(INTEL, 0x4b2b), LPSS_BXT_SSP },
1492 	{ PCI_VDEVICE(INTEL, 0x4b37), LPSS_BXT_SSP },
1493 	/* JSL */
1494 	{ PCI_VDEVICE(INTEL, 0x4daa), LPSS_CNL_SSP },
1495 	{ PCI_VDEVICE(INTEL, 0x4dab), LPSS_CNL_SSP },
1496 	{ PCI_VDEVICE(INTEL, 0x4dfb), LPSS_CNL_SSP },
1497 	/* TGL-H */
1498 	{ PCI_VDEVICE(INTEL, 0x43aa), LPSS_CNL_SSP },
1499 	{ PCI_VDEVICE(INTEL, 0x43ab), LPSS_CNL_SSP },
1500 	{ PCI_VDEVICE(INTEL, 0x43fb), LPSS_CNL_SSP },
1501 	{ PCI_VDEVICE(INTEL, 0x43fd), LPSS_CNL_SSP },
1502 	/* APL */
1503 	{ PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP },
1504 	{ PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP },
1505 	{ PCI_VDEVICE(INTEL, 0x5ac6), LPSS_BXT_SSP },
1506 	/* CNL-LP */
1507 	{ PCI_VDEVICE(INTEL, 0x9daa), LPSS_CNL_SSP },
1508 	{ PCI_VDEVICE(INTEL, 0x9dab), LPSS_CNL_SSP },
1509 	{ PCI_VDEVICE(INTEL, 0x9dfb), LPSS_CNL_SSP },
1510 	/* CNL-H */
1511 	{ PCI_VDEVICE(INTEL, 0xa32a), LPSS_CNL_SSP },
1512 	{ PCI_VDEVICE(INTEL, 0xa32b), LPSS_CNL_SSP },
1513 	{ PCI_VDEVICE(INTEL, 0xa37b), LPSS_CNL_SSP },
1514 	/* CML-LP */
1515 	{ PCI_VDEVICE(INTEL, 0x02aa), LPSS_CNL_SSP },
1516 	{ PCI_VDEVICE(INTEL, 0x02ab), LPSS_CNL_SSP },
1517 	{ PCI_VDEVICE(INTEL, 0x02fb), LPSS_CNL_SSP },
1518 	/* CML-H */
1519 	{ PCI_VDEVICE(INTEL, 0x06aa), LPSS_CNL_SSP },
1520 	{ PCI_VDEVICE(INTEL, 0x06ab), LPSS_CNL_SSP },
1521 	{ PCI_VDEVICE(INTEL, 0x06fb), LPSS_CNL_SSP },
1522 	/* TGL-LP */
1523 	{ PCI_VDEVICE(INTEL, 0xa0aa), LPSS_CNL_SSP },
1524 	{ PCI_VDEVICE(INTEL, 0xa0ab), LPSS_CNL_SSP },
1525 	{ PCI_VDEVICE(INTEL, 0xa0de), LPSS_CNL_SSP },
1526 	{ PCI_VDEVICE(INTEL, 0xa0df), LPSS_CNL_SSP },
1527 	{ PCI_VDEVICE(INTEL, 0xa0fb), LPSS_CNL_SSP },
1528 	{ PCI_VDEVICE(INTEL, 0xa0fd), LPSS_CNL_SSP },
1529 	{ PCI_VDEVICE(INTEL, 0xa0fe), LPSS_CNL_SSP },
1530 	{ },
1531 };
1532 
1533 static const struct of_device_id pxa2xx_spi_of_match[] = {
1534 	{ .compatible = "marvell,mmp2-ssp", .data = (void *)MMP2_SSP },
1535 	{},
1536 };
1537 MODULE_DEVICE_TABLE(of, pxa2xx_spi_of_match);
1538 
1539 #ifdef CONFIG_ACPI
1540 
pxa2xx_spi_get_port_id(struct device * dev)1541 static int pxa2xx_spi_get_port_id(struct device *dev)
1542 {
1543 	struct acpi_device *adev;
1544 	unsigned int devid;
1545 	int port_id = -1;
1546 
1547 	adev = ACPI_COMPANION(dev);
1548 	if (adev && adev->pnp.unique_id &&
1549 	    !kstrtouint(adev->pnp.unique_id, 0, &devid))
1550 		port_id = devid;
1551 	return port_id;
1552 }
1553 
1554 #else /* !CONFIG_ACPI */
1555 
pxa2xx_spi_get_port_id(struct device * dev)1556 static int pxa2xx_spi_get_port_id(struct device *dev)
1557 {
1558 	return -1;
1559 }
1560 
1561 #endif /* CONFIG_ACPI */
1562 
1563 
1564 #ifdef CONFIG_PCI
1565 
pxa2xx_spi_idma_filter(struct dma_chan * chan,void * param)1566 static bool pxa2xx_spi_idma_filter(struct dma_chan *chan, void *param)
1567 {
1568 	return param == chan->device->dev;
1569 }
1570 
1571 #endif /* CONFIG_PCI */
1572 
1573 static struct pxa2xx_spi_controller *
pxa2xx_spi_init_pdata(struct platform_device * pdev)1574 pxa2xx_spi_init_pdata(struct platform_device *pdev)
1575 {
1576 	struct pxa2xx_spi_controller *pdata;
1577 	struct ssp_device *ssp;
1578 	struct resource *res;
1579 	struct device *parent = pdev->dev.parent;
1580 	struct pci_dev *pcidev = dev_is_pci(parent) ? to_pci_dev(parent) : NULL;
1581 	const struct pci_device_id *pcidev_id = NULL;
1582 	enum pxa_ssp_type type;
1583 	const void *match;
1584 
1585 	if (pcidev)
1586 		pcidev_id = pci_match_id(pxa2xx_spi_pci_compound_match, pcidev);
1587 
1588 	match = device_get_match_data(&pdev->dev);
1589 	if (match)
1590 		type = (enum pxa_ssp_type)match;
1591 	else if (pcidev_id)
1592 		type = (enum pxa_ssp_type)pcidev_id->driver_data;
1593 	else
1594 		return ERR_PTR(-EINVAL);
1595 
1596 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
1597 	if (!pdata)
1598 		return ERR_PTR(-ENOMEM);
1599 
1600 	ssp = &pdata->ssp;
1601 
1602 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1603 	ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
1604 	if (IS_ERR(ssp->mmio_base))
1605 		return ERR_CAST(ssp->mmio_base);
1606 
1607 	ssp->phys_base = res->start;
1608 
1609 #ifdef CONFIG_PCI
1610 	if (pcidev_id) {
1611 		pdata->tx_param = parent;
1612 		pdata->rx_param = parent;
1613 		pdata->dma_filter = pxa2xx_spi_idma_filter;
1614 	}
1615 #endif
1616 
1617 	ssp->clk = devm_clk_get(&pdev->dev, NULL);
1618 	if (IS_ERR(ssp->clk))
1619 		return ERR_CAST(ssp->clk);
1620 
1621 	ssp->irq = platform_get_irq(pdev, 0);
1622 	if (ssp->irq < 0)
1623 		return ERR_PTR(ssp->irq);
1624 
1625 	ssp->type = type;
1626 	ssp->dev = &pdev->dev;
1627 	ssp->port_id = pxa2xx_spi_get_port_id(&pdev->dev);
1628 
1629 	pdata->is_slave = device_property_read_bool(&pdev->dev, "spi-slave");
1630 	pdata->num_chipselect = 1;
1631 	pdata->enable_dma = true;
1632 	pdata->dma_burst_size = 1;
1633 
1634 	return pdata;
1635 }
1636 
pxa2xx_spi_fw_translate_cs(struct spi_controller * controller,unsigned int cs)1637 static int pxa2xx_spi_fw_translate_cs(struct spi_controller *controller,
1638 				      unsigned int cs)
1639 {
1640 	struct driver_data *drv_data = spi_controller_get_devdata(controller);
1641 
1642 	if (has_acpi_companion(&drv_data->pdev->dev)) {
1643 		switch (drv_data->ssp_type) {
1644 		/*
1645 		 * For Atoms the ACPI DeviceSelection used by the Windows
1646 		 * driver starts from 1 instead of 0 so translate it here
1647 		 * to match what Linux expects.
1648 		 */
1649 		case LPSS_BYT_SSP:
1650 		case LPSS_BSW_SSP:
1651 			return cs - 1;
1652 
1653 		default:
1654 			break;
1655 		}
1656 	}
1657 
1658 	return cs;
1659 }
1660 
pxa2xx_spi_max_dma_transfer_size(struct spi_device * spi)1661 static size_t pxa2xx_spi_max_dma_transfer_size(struct spi_device *spi)
1662 {
1663 	return MAX_DMA_LEN;
1664 }
1665 
pxa2xx_spi_probe(struct platform_device * pdev)1666 static int pxa2xx_spi_probe(struct platform_device *pdev)
1667 {
1668 	struct device *dev = &pdev->dev;
1669 	struct pxa2xx_spi_controller *platform_info;
1670 	struct spi_controller *controller;
1671 	struct driver_data *drv_data;
1672 	struct ssp_device *ssp;
1673 	const struct lpss_config *config;
1674 	int status, count;
1675 	u32 tmp;
1676 
1677 	platform_info = dev_get_platdata(dev);
1678 	if (!platform_info) {
1679 		platform_info = pxa2xx_spi_init_pdata(pdev);
1680 		if (IS_ERR(platform_info)) {
1681 			dev_err(&pdev->dev, "missing platform data\n");
1682 			return PTR_ERR(platform_info);
1683 		}
1684 	}
1685 
1686 	ssp = pxa_ssp_request(pdev->id, pdev->name);
1687 	if (!ssp)
1688 		ssp = &platform_info->ssp;
1689 
1690 	if (!ssp->mmio_base) {
1691 		dev_err(&pdev->dev, "failed to get ssp\n");
1692 		return -ENODEV;
1693 	}
1694 
1695 	if (platform_info->is_slave)
1696 		controller = devm_spi_alloc_slave(dev, sizeof(*drv_data));
1697 	else
1698 		controller = devm_spi_alloc_master(dev, sizeof(*drv_data));
1699 
1700 	if (!controller) {
1701 		dev_err(&pdev->dev, "cannot alloc spi_controller\n");
1702 		pxa_ssp_free(ssp);
1703 		return -ENOMEM;
1704 	}
1705 	drv_data = spi_controller_get_devdata(controller);
1706 	drv_data->controller = controller;
1707 	drv_data->controller_info = platform_info;
1708 	drv_data->pdev = pdev;
1709 	drv_data->ssp = ssp;
1710 
1711 	controller->dev.of_node = pdev->dev.of_node;
1712 	/* the spi->mode bits understood by this driver: */
1713 	controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
1714 
1715 	controller->bus_num = ssp->port_id;
1716 	controller->dma_alignment = DMA_ALIGNMENT;
1717 	controller->cleanup = cleanup;
1718 	controller->setup = setup;
1719 	controller->set_cs = pxa2xx_spi_set_cs;
1720 	controller->transfer_one = pxa2xx_spi_transfer_one;
1721 	controller->slave_abort = pxa2xx_spi_slave_abort;
1722 	controller->handle_err = pxa2xx_spi_handle_err;
1723 	controller->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
1724 	controller->fw_translate_cs = pxa2xx_spi_fw_translate_cs;
1725 	controller->auto_runtime_pm = true;
1726 	controller->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
1727 
1728 	drv_data->ssp_type = ssp->type;
1729 
1730 	drv_data->ioaddr = ssp->mmio_base;
1731 	drv_data->ssdr_physical = ssp->phys_base + SSDR;
1732 	if (pxa25x_ssp_comp(drv_data)) {
1733 		switch (drv_data->ssp_type) {
1734 		case QUARK_X1000_SSP:
1735 			controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1736 			break;
1737 		default:
1738 			controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1739 			break;
1740 		}
1741 
1742 		drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
1743 		drv_data->dma_cr1 = 0;
1744 		drv_data->clear_sr = SSSR_ROR;
1745 		drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
1746 	} else {
1747 		controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1748 		drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
1749 		drv_data->dma_cr1 = DEFAULT_DMA_CR1;
1750 		drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
1751 		drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS
1752 						| SSSR_ROR | SSSR_TUR;
1753 	}
1754 
1755 	status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
1756 			drv_data);
1757 	if (status < 0) {
1758 		dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
1759 		goto out_error_controller_alloc;
1760 	}
1761 
1762 	/* Setup DMA if requested */
1763 	if (platform_info->enable_dma) {
1764 		status = pxa2xx_spi_dma_setup(drv_data);
1765 		if (status) {
1766 			dev_warn(dev, "no DMA channels available, using PIO\n");
1767 			platform_info->enable_dma = false;
1768 		} else {
1769 			controller->can_dma = pxa2xx_spi_can_dma;
1770 			controller->max_dma_len = MAX_DMA_LEN;
1771 			controller->max_transfer_size =
1772 				pxa2xx_spi_max_dma_transfer_size;
1773 		}
1774 	}
1775 
1776 	/* Enable SOC clock */
1777 	status = clk_prepare_enable(ssp->clk);
1778 	if (status)
1779 		goto out_error_dma_irq_alloc;
1780 
1781 	controller->max_speed_hz = clk_get_rate(ssp->clk);
1782 	/*
1783 	 * Set minimum speed for all other platforms than Intel Quark which is
1784 	 * able do under 1 Hz transfers.
1785 	 */
1786 	if (!pxa25x_ssp_comp(drv_data))
1787 		controller->min_speed_hz =
1788 			DIV_ROUND_UP(controller->max_speed_hz, 4096);
1789 	else if (!is_quark_x1000_ssp(drv_data))
1790 		controller->min_speed_hz =
1791 			DIV_ROUND_UP(controller->max_speed_hz, 512);
1792 
1793 	/* Load default SSP configuration */
1794 	pxa2xx_spi_write(drv_data, SSCR0, 0);
1795 	switch (drv_data->ssp_type) {
1796 	case QUARK_X1000_SSP:
1797 		tmp = QUARK_X1000_SSCR1_RxTresh(RX_THRESH_QUARK_X1000_DFLT) |
1798 		      QUARK_X1000_SSCR1_TxTresh(TX_THRESH_QUARK_X1000_DFLT);
1799 		pxa2xx_spi_write(drv_data, SSCR1, tmp);
1800 
1801 		/* using the Motorola SPI protocol and use 8 bit frame */
1802 		tmp = QUARK_X1000_SSCR0_Motorola | QUARK_X1000_SSCR0_DataSize(8);
1803 		pxa2xx_spi_write(drv_data, SSCR0, tmp);
1804 		break;
1805 	case CE4100_SSP:
1806 		tmp = CE4100_SSCR1_RxTresh(RX_THRESH_CE4100_DFLT) |
1807 		      CE4100_SSCR1_TxTresh(TX_THRESH_CE4100_DFLT);
1808 		pxa2xx_spi_write(drv_data, SSCR1, tmp);
1809 		tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
1810 		pxa2xx_spi_write(drv_data, SSCR0, tmp);
1811 		break;
1812 	default:
1813 
1814 		if (spi_controller_is_slave(controller)) {
1815 			tmp = SSCR1_SCFR |
1816 			      SSCR1_SCLKDIR |
1817 			      SSCR1_SFRMDIR |
1818 			      SSCR1_RxTresh(2) |
1819 			      SSCR1_TxTresh(1) |
1820 			      SSCR1_SPH;
1821 		} else {
1822 			tmp = SSCR1_RxTresh(RX_THRESH_DFLT) |
1823 			      SSCR1_TxTresh(TX_THRESH_DFLT);
1824 		}
1825 		pxa2xx_spi_write(drv_data, SSCR1, tmp);
1826 		tmp = SSCR0_Motorola | SSCR0_DataSize(8);
1827 		if (!spi_controller_is_slave(controller))
1828 			tmp |= SSCR0_SCR(2);
1829 		pxa2xx_spi_write(drv_data, SSCR0, tmp);
1830 		break;
1831 	}
1832 
1833 	if (!pxa25x_ssp_comp(drv_data))
1834 		pxa2xx_spi_write(drv_data, SSTO, 0);
1835 
1836 	if (!is_quark_x1000_ssp(drv_data))
1837 		pxa2xx_spi_write(drv_data, SSPSP, 0);
1838 
1839 	if (is_lpss_ssp(drv_data)) {
1840 		lpss_ssp_setup(drv_data);
1841 		config = lpss_get_config(drv_data);
1842 		if (config->reg_capabilities >= 0) {
1843 			tmp = __lpss_ssp_read_priv(drv_data,
1844 						   config->reg_capabilities);
1845 			tmp &= LPSS_CAPS_CS_EN_MASK;
1846 			tmp >>= LPSS_CAPS_CS_EN_SHIFT;
1847 			platform_info->num_chipselect = ffz(tmp);
1848 		} else if (config->cs_num) {
1849 			platform_info->num_chipselect = config->cs_num;
1850 		}
1851 	}
1852 	controller->num_chipselect = platform_info->num_chipselect;
1853 
1854 	count = gpiod_count(&pdev->dev, "cs");
1855 	if (count > 0) {
1856 		int i;
1857 
1858 		controller->num_chipselect = max_t(int, count,
1859 			controller->num_chipselect);
1860 
1861 		drv_data->cs_gpiods = devm_kcalloc(&pdev->dev,
1862 			controller->num_chipselect, sizeof(struct gpio_desc *),
1863 			GFP_KERNEL);
1864 		if (!drv_data->cs_gpiods) {
1865 			status = -ENOMEM;
1866 			goto out_error_clock_enabled;
1867 		}
1868 
1869 		for (i = 0; i < controller->num_chipselect; i++) {
1870 			struct gpio_desc *gpiod;
1871 
1872 			gpiod = devm_gpiod_get_index(dev, "cs", i, GPIOD_ASIS);
1873 			if (IS_ERR(gpiod)) {
1874 				/* Means use native chip select */
1875 				if (PTR_ERR(gpiod) == -ENOENT)
1876 					continue;
1877 
1878 				status = PTR_ERR(gpiod);
1879 				goto out_error_clock_enabled;
1880 			} else {
1881 				drv_data->cs_gpiods[i] = gpiod;
1882 			}
1883 		}
1884 	}
1885 
1886 	if (platform_info->is_slave) {
1887 		drv_data->gpiod_ready = devm_gpiod_get_optional(dev,
1888 						"ready", GPIOD_OUT_LOW);
1889 		if (IS_ERR(drv_data->gpiod_ready)) {
1890 			status = PTR_ERR(drv_data->gpiod_ready);
1891 			goto out_error_clock_enabled;
1892 		}
1893 	}
1894 
1895 	pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
1896 	pm_runtime_use_autosuspend(&pdev->dev);
1897 	pm_runtime_set_active(&pdev->dev);
1898 	pm_runtime_enable(&pdev->dev);
1899 
1900 	/* Register with the SPI framework */
1901 	platform_set_drvdata(pdev, drv_data);
1902 	status = spi_register_controller(controller);
1903 	if (status != 0) {
1904 		dev_err(&pdev->dev, "problem registering spi controller\n");
1905 		goto out_error_pm_runtime_enabled;
1906 	}
1907 
1908 	return status;
1909 
1910 out_error_pm_runtime_enabled:
1911 	pm_runtime_disable(&pdev->dev);
1912 
1913 out_error_clock_enabled:
1914 	clk_disable_unprepare(ssp->clk);
1915 
1916 out_error_dma_irq_alloc:
1917 	pxa2xx_spi_dma_release(drv_data);
1918 	free_irq(ssp->irq, drv_data);
1919 
1920 out_error_controller_alloc:
1921 	pxa_ssp_free(ssp);
1922 	return status;
1923 }
1924 
pxa2xx_spi_remove(struct platform_device * pdev)1925 static int pxa2xx_spi_remove(struct platform_device *pdev)
1926 {
1927 	struct driver_data *drv_data = platform_get_drvdata(pdev);
1928 	struct ssp_device *ssp = drv_data->ssp;
1929 
1930 	pm_runtime_get_sync(&pdev->dev);
1931 
1932 	spi_unregister_controller(drv_data->controller);
1933 
1934 	/* Disable the SSP at the peripheral and SOC level */
1935 	pxa2xx_spi_write(drv_data, SSCR0, 0);
1936 	clk_disable_unprepare(ssp->clk);
1937 
1938 	/* Release DMA */
1939 	if (drv_data->controller_info->enable_dma)
1940 		pxa2xx_spi_dma_release(drv_data);
1941 
1942 	pm_runtime_put_noidle(&pdev->dev);
1943 	pm_runtime_disable(&pdev->dev);
1944 
1945 	/* Release IRQ */
1946 	free_irq(ssp->irq, drv_data);
1947 
1948 	/* Release SSP */
1949 	pxa_ssp_free(ssp);
1950 
1951 	return 0;
1952 }
1953 
1954 #ifdef CONFIG_PM_SLEEP
pxa2xx_spi_suspend(struct device * dev)1955 static int pxa2xx_spi_suspend(struct device *dev)
1956 {
1957 	struct driver_data *drv_data = dev_get_drvdata(dev);
1958 	struct ssp_device *ssp = drv_data->ssp;
1959 	int status;
1960 
1961 	status = spi_controller_suspend(drv_data->controller);
1962 	if (status != 0)
1963 		return status;
1964 	pxa2xx_spi_write(drv_data, SSCR0, 0);
1965 
1966 	if (!pm_runtime_suspended(dev))
1967 		clk_disable_unprepare(ssp->clk);
1968 
1969 	return 0;
1970 }
1971 
pxa2xx_spi_resume(struct device * dev)1972 static int pxa2xx_spi_resume(struct device *dev)
1973 {
1974 	struct driver_data *drv_data = dev_get_drvdata(dev);
1975 	struct ssp_device *ssp = drv_data->ssp;
1976 	int status;
1977 
1978 	/* Enable the SSP clock */
1979 	if (!pm_runtime_suspended(dev)) {
1980 		status = clk_prepare_enable(ssp->clk);
1981 		if (status)
1982 			return status;
1983 	}
1984 
1985 	/* Start the queue running */
1986 	return spi_controller_resume(drv_data->controller);
1987 }
1988 #endif
1989 
1990 #ifdef CONFIG_PM
pxa2xx_spi_runtime_suspend(struct device * dev)1991 static int pxa2xx_spi_runtime_suspend(struct device *dev)
1992 {
1993 	struct driver_data *drv_data = dev_get_drvdata(dev);
1994 
1995 	clk_disable_unprepare(drv_data->ssp->clk);
1996 	return 0;
1997 }
1998 
pxa2xx_spi_runtime_resume(struct device * dev)1999 static int pxa2xx_spi_runtime_resume(struct device *dev)
2000 {
2001 	struct driver_data *drv_data = dev_get_drvdata(dev);
2002 	int status;
2003 
2004 	status = clk_prepare_enable(drv_data->ssp->clk);
2005 	return status;
2006 }
2007 #endif
2008 
2009 static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
2010 	SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
2011 	SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
2012 			   pxa2xx_spi_runtime_resume, NULL)
2013 };
2014 
2015 static struct platform_driver driver = {
2016 	.driver = {
2017 		.name	= "pxa2xx-spi",
2018 		.pm	= &pxa2xx_spi_pm_ops,
2019 		.acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
2020 		.of_match_table = of_match_ptr(pxa2xx_spi_of_match),
2021 	},
2022 	.probe = pxa2xx_spi_probe,
2023 	.remove = pxa2xx_spi_remove,
2024 };
2025 
pxa2xx_spi_init(void)2026 static int __init pxa2xx_spi_init(void)
2027 {
2028 	return platform_driver_register(&driver);
2029 }
2030 subsys_initcall(pxa2xx_spi_init);
2031 
pxa2xx_spi_exit(void)2032 static void __exit pxa2xx_spi_exit(void)
2033 {
2034 	platform_driver_unregister(&driver);
2035 }
2036 module_exit(pxa2xx_spi_exit);
2037 
2038 MODULE_SOFTDEP("pre: dw_dmac");
2039