xref: /linux/drivers/spi/spi-tegra210-quad.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-only
2 //
3 // Copyright (C) 2020 NVIDIA CORPORATION.
4 
5 #include <linux/clk.h>
6 #include <linux/completion.h>
7 #include <linux/delay.h>
8 #include <linux/dmaengine.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/dmapool.h>
11 #include <linux/err.h>
12 #include <linux/interrupt.h>
13 #include <linux/io.h>
14 #include <linux/iopoll.h>
15 #include <linux/kernel.h>
16 #include <linux/kthread.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/of.h>
21 #include <linux/reset.h>
22 #include <linux/spi/spi.h>
23 #include <linux/acpi.h>
24 #include <linux/property.h>
25 
26 #define QSPI_COMMAND1				0x000
27 #define QSPI_BIT_LENGTH(x)			(((x) & 0x1f) << 0)
28 #define QSPI_PACKED				BIT(5)
29 #define QSPI_INTERFACE_WIDTH_MASK		(0x03 << 7)
30 #define QSPI_INTERFACE_WIDTH(x)			(((x) & 0x03) << 7)
31 #define QSPI_INTERFACE_WIDTH_SINGLE		QSPI_INTERFACE_WIDTH(0)
32 #define QSPI_INTERFACE_WIDTH_DUAL		QSPI_INTERFACE_WIDTH(1)
33 #define QSPI_INTERFACE_WIDTH_QUAD		QSPI_INTERFACE_WIDTH(2)
34 #define QSPI_SDR_DDR_SEL			BIT(9)
35 #define QSPI_TX_EN				BIT(11)
36 #define QSPI_RX_EN				BIT(12)
37 #define QSPI_CS_SW_VAL				BIT(20)
38 #define QSPI_CS_SW_HW				BIT(21)
39 
40 #define QSPI_CS_POL_INACTIVE(n)			(1 << (22 + (n)))
41 #define QSPI_CS_POL_INACTIVE_MASK		(0xF << 22)
42 #define QSPI_CS_SEL_0				(0 << 26)
43 #define QSPI_CS_SEL_1				(1 << 26)
44 #define QSPI_CS_SEL_2				(2 << 26)
45 #define QSPI_CS_SEL_3				(3 << 26)
46 #define QSPI_CS_SEL_MASK			(3 << 26)
47 #define QSPI_CS_SEL(x)				(((x) & 0x3) << 26)
48 
49 #define QSPI_CONTROL_MODE_0			(0 << 28)
50 #define QSPI_CONTROL_MODE_3			(3 << 28)
51 #define QSPI_CONTROL_MODE_MASK			(3 << 28)
52 #define QSPI_M_S				BIT(30)
53 #define QSPI_PIO				BIT(31)
54 
55 #define QSPI_COMMAND2				0x004
56 #define QSPI_TX_TAP_DELAY(x)			(((x) & 0x3f) << 10)
57 #define QSPI_RX_TAP_DELAY(x)			(((x) & 0xff) << 0)
58 
59 #define QSPI_CS_TIMING1				0x008
60 #define QSPI_SETUP_HOLD(setup, hold)		(((setup) << 4) | (hold))
61 
62 #define QSPI_CS_TIMING2				0x00c
63 #define CYCLES_BETWEEN_PACKETS_0(x)		(((x) & 0x1f) << 0)
64 #define CS_ACTIVE_BETWEEN_PACKETS_0		BIT(5)
65 
66 #define QSPI_TRANS_STATUS			0x010
67 #define QSPI_BLK_CNT(val)			(((val) >> 0) & 0xffff)
68 #define QSPI_RDY				BIT(30)
69 
70 #define QSPI_FIFO_STATUS			0x014
71 #define QSPI_RX_FIFO_EMPTY			BIT(0)
72 #define QSPI_RX_FIFO_FULL			BIT(1)
73 #define QSPI_TX_FIFO_EMPTY			BIT(2)
74 #define QSPI_TX_FIFO_FULL			BIT(3)
75 #define QSPI_RX_FIFO_UNF			BIT(4)
76 #define QSPI_RX_FIFO_OVF			BIT(5)
77 #define QSPI_TX_FIFO_UNF			BIT(6)
78 #define QSPI_TX_FIFO_OVF			BIT(7)
79 #define QSPI_ERR				BIT(8)
80 #define QSPI_TX_FIFO_FLUSH			BIT(14)
81 #define QSPI_RX_FIFO_FLUSH			BIT(15)
82 #define QSPI_TX_FIFO_EMPTY_COUNT(val)		(((val) >> 16) & 0x7f)
83 #define QSPI_RX_FIFO_FULL_COUNT(val)		(((val) >> 23) & 0x7f)
84 
85 #define QSPI_FIFO_ERROR				(QSPI_RX_FIFO_UNF | \
86 						 QSPI_RX_FIFO_OVF | \
87 						 QSPI_TX_FIFO_UNF | \
88 						 QSPI_TX_FIFO_OVF)
89 #define QSPI_FIFO_EMPTY				(QSPI_RX_FIFO_EMPTY | \
90 						 QSPI_TX_FIFO_EMPTY)
91 
92 #define QSPI_TX_DATA				0x018
93 #define QSPI_RX_DATA				0x01c
94 
95 #define QSPI_DMA_CTL				0x020
96 #define QSPI_TX_TRIG(n)				(((n) & 0x3) << 15)
97 #define QSPI_TX_TRIG_1				QSPI_TX_TRIG(0)
98 #define QSPI_TX_TRIG_4				QSPI_TX_TRIG(1)
99 #define QSPI_TX_TRIG_8				QSPI_TX_TRIG(2)
100 #define QSPI_TX_TRIG_16				QSPI_TX_TRIG(3)
101 
102 #define QSPI_RX_TRIG(n)				(((n) & 0x3) << 19)
103 #define QSPI_RX_TRIG_1				QSPI_RX_TRIG(0)
104 #define QSPI_RX_TRIG_4				QSPI_RX_TRIG(1)
105 #define QSPI_RX_TRIG_8				QSPI_RX_TRIG(2)
106 #define QSPI_RX_TRIG_16				QSPI_RX_TRIG(3)
107 
108 #define QSPI_DMA_EN				BIT(31)
109 
110 #define QSPI_DMA_BLK				0x024
111 #define QSPI_DMA_BLK_SET(x)			(((x) & 0xffff) << 0)
112 
113 #define QSPI_TX_FIFO				0x108
114 #define QSPI_RX_FIFO				0x188
115 
116 #define QSPI_FIFO_DEPTH				64
117 
118 #define QSPI_INTR_MASK				0x18c
119 #define QSPI_INTR_RX_FIFO_UNF_MASK		BIT(25)
120 #define QSPI_INTR_RX_FIFO_OVF_MASK		BIT(26)
121 #define QSPI_INTR_TX_FIFO_UNF_MASK		BIT(27)
122 #define QSPI_INTR_TX_FIFO_OVF_MASK		BIT(28)
123 #define QSPI_INTR_RDY_MASK			BIT(29)
124 #define QSPI_INTR_RX_TX_FIFO_ERR		(QSPI_INTR_RX_FIFO_UNF_MASK | \
125 						 QSPI_INTR_RX_FIFO_OVF_MASK | \
126 						 QSPI_INTR_TX_FIFO_UNF_MASK | \
127 						 QSPI_INTR_TX_FIFO_OVF_MASK)
128 
129 #define QSPI_MISC_REG                           0x194
130 #define QSPI_NUM_DUMMY_CYCLE(x)			(((x) & 0xff) << 0)
131 #define QSPI_DUMMY_CYCLES_MAX			0xff
132 
133 #define QSPI_CMB_SEQ_CMD			0x19c
134 #define QSPI_COMMAND_VALUE_SET(X)		(((x) & 0xFF) << 0)
135 
136 #define QSPI_CMB_SEQ_CMD_CFG			0x1a0
137 #define QSPI_COMMAND_X1_X2_X4(x)		(((x) & 0x3) << 13)
138 #define QSPI_COMMAND_X1_X2_X4_MASK		(0x03 << 13)
139 #define QSPI_COMMAND_SDR_DDR			BIT(12)
140 #define QSPI_COMMAND_SIZE_SET(x)		(((x) & 0xFF) << 0)
141 
142 #define QSPI_GLOBAL_CONFIG			0X1a4
143 #define QSPI_CMB_SEQ_EN				BIT(0)
144 #define QSPI_TPM_WAIT_POLL_EN			BIT(1)
145 
146 #define QSPI_CMB_SEQ_ADDR			0x1a8
147 #define QSPI_ADDRESS_VALUE_SET(X)		(((x) & 0xFFFF) << 0)
148 
149 #define QSPI_CMB_SEQ_ADDR_CFG			0x1ac
150 #define QSPI_ADDRESS_X1_X2_X4(x)		(((x) & 0x3) << 13)
151 #define QSPI_ADDRESS_X1_X2_X4_MASK		(0x03 << 13)
152 #define QSPI_ADDRESS_SDR_DDR			BIT(12)
153 #define QSPI_ADDRESS_SIZE_SET(x)		(((x) & 0xFF) << 0)
154 
155 #define DATA_DIR_TX				BIT(0)
156 #define DATA_DIR_RX				BIT(1)
157 
158 #define QSPI_DMA_TIMEOUT			(msecs_to_jiffies(1000))
159 #define DEFAULT_QSPI_DMA_BUF_LEN		(64 * 1024)
160 #define CMD_TRANSFER				0
161 #define ADDR_TRANSFER				1
162 #define DATA_TRANSFER				2
163 
164 struct tegra_qspi_soc_data {
165 	bool has_dma;
166 	bool cmb_xfer_capable;
167 	bool supports_tpm;
168 	unsigned int cs_count;
169 };
170 
171 struct tegra_qspi_client_data {
172 	int tx_clk_tap_delay;
173 	int rx_clk_tap_delay;
174 };
175 
176 struct tegra_qspi {
177 	struct device				*dev;
178 	struct spi_controller			*host;
179 	/* lock to protect data accessed by irq */
180 	spinlock_t				lock;
181 
182 	struct clk				*clk;
183 	void __iomem				*base;
184 	phys_addr_t				phys;
185 	unsigned int				irq;
186 
187 	u32					cur_speed;
188 	unsigned int				cur_pos;
189 	unsigned int				words_per_32bit;
190 	unsigned int				bytes_per_word;
191 	unsigned int				curr_dma_words;
192 	unsigned int				cur_direction;
193 
194 	unsigned int				cur_rx_pos;
195 	unsigned int				cur_tx_pos;
196 
197 	unsigned int				dma_buf_size;
198 	unsigned int				max_buf_size;
199 	bool					is_curr_dma_xfer;
200 
201 	struct completion			rx_dma_complete;
202 	struct completion			tx_dma_complete;
203 
204 	u32					tx_status;
205 	u32					rx_status;
206 	u32					status_reg;
207 	bool					is_packed;
208 	bool					use_dma;
209 
210 	u32					command1_reg;
211 	u32					dma_control_reg;
212 	u32					def_command1_reg;
213 	u32					def_command2_reg;
214 	u32					spi_cs_timing1;
215 	u32					spi_cs_timing2;
216 	u8					dummy_cycles;
217 
218 	struct completion			xfer_completion;
219 	struct spi_transfer			*curr_xfer;
220 
221 	struct dma_chan				*rx_dma_chan;
222 	u32					*rx_dma_buf;
223 	dma_addr_t				rx_dma_phys;
224 	struct dma_async_tx_descriptor		*rx_dma_desc;
225 
226 	struct dma_chan				*tx_dma_chan;
227 	u32					*tx_dma_buf;
228 	dma_addr_t				tx_dma_phys;
229 	struct dma_async_tx_descriptor		*tx_dma_desc;
230 	const struct tegra_qspi_soc_data	*soc_data;
231 };
232 
233 static inline u32 tegra_qspi_readl(struct tegra_qspi *tqspi, unsigned long offset)
234 {
235 	return readl(tqspi->base + offset);
236 }
237 
238 static inline void tegra_qspi_writel(struct tegra_qspi *tqspi, u32 value, unsigned long offset)
239 {
240 	writel(value, tqspi->base + offset);
241 
242 	/* read back register to make sure that register writes completed */
243 	if (offset != QSPI_TX_FIFO)
244 		readl(tqspi->base + QSPI_COMMAND1);
245 }
246 
247 static void tegra_qspi_mask_clear_irq(struct tegra_qspi *tqspi)
248 {
249 	u32 value;
250 
251 	/* write 1 to clear status register */
252 	value = tegra_qspi_readl(tqspi, QSPI_TRANS_STATUS);
253 	tegra_qspi_writel(tqspi, value, QSPI_TRANS_STATUS);
254 
255 	value = tegra_qspi_readl(tqspi, QSPI_INTR_MASK);
256 	if (!(value & QSPI_INTR_RDY_MASK)) {
257 		value |= (QSPI_INTR_RDY_MASK | QSPI_INTR_RX_TX_FIFO_ERR);
258 		tegra_qspi_writel(tqspi, value, QSPI_INTR_MASK);
259 	}
260 
261 	/* clear fifo status error if any */
262 	value = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
263 	if (value & QSPI_ERR)
264 		tegra_qspi_writel(tqspi, QSPI_ERR | QSPI_FIFO_ERROR, QSPI_FIFO_STATUS);
265 }
266 
267 static unsigned int
268 tegra_qspi_calculate_curr_xfer_param(struct tegra_qspi *tqspi, struct spi_transfer *t)
269 {
270 	unsigned int max_word, max_len, total_fifo_words;
271 	unsigned int remain_len = t->len - tqspi->cur_pos;
272 	unsigned int bits_per_word = t->bits_per_word;
273 
274 	tqspi->bytes_per_word = DIV_ROUND_UP(bits_per_word, 8);
275 
276 	/*
277 	 * Tegra QSPI controller supports packed or unpacked mode transfers.
278 	 * Packed mode is used for data transfers using 8, 16, or 32 bits per
279 	 * word with a minimum transfer of 1 word and for all other transfers
280 	 * unpacked mode will be used.
281 	 */
282 
283 	if ((bits_per_word == 8 || bits_per_word == 16 ||
284 	     bits_per_word == 32) && t->len > 3) {
285 		tqspi->is_packed = true;
286 		tqspi->words_per_32bit = 32 / bits_per_word;
287 	} else {
288 		tqspi->is_packed = false;
289 		tqspi->words_per_32bit = 1;
290 	}
291 
292 	if (tqspi->is_packed) {
293 		max_len = min(remain_len, tqspi->max_buf_size);
294 		tqspi->curr_dma_words = max_len / tqspi->bytes_per_word;
295 		total_fifo_words = (max_len + 3) / 4;
296 	} else {
297 		max_word = (remain_len - 1) / tqspi->bytes_per_word + 1;
298 		max_word = min(max_word, tqspi->max_buf_size / 4);
299 		tqspi->curr_dma_words = max_word;
300 		total_fifo_words = max_word;
301 	}
302 
303 	return total_fifo_words;
304 }
305 
306 static unsigned int
307 tegra_qspi_fill_tx_fifo_from_client_txbuf(struct tegra_qspi *tqspi, struct spi_transfer *t)
308 {
309 	unsigned int written_words, fifo_words_left, count;
310 	unsigned int len, tx_empty_count, max_n_32bit, i;
311 	u8 *tx_buf = (u8 *)t->tx_buf + tqspi->cur_tx_pos;
312 	u32 fifo_status;
313 
314 	fifo_status = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
315 	tx_empty_count = QSPI_TX_FIFO_EMPTY_COUNT(fifo_status);
316 
317 	if (tqspi->is_packed) {
318 		fifo_words_left = tx_empty_count * tqspi->words_per_32bit;
319 		written_words = min(fifo_words_left, tqspi->curr_dma_words);
320 		len = written_words * tqspi->bytes_per_word;
321 		max_n_32bit = DIV_ROUND_UP(len, 4);
322 		for (count = 0; count < max_n_32bit; count++) {
323 			u32 x = 0;
324 
325 			for (i = 0; (i < 4) && len; i++, len--)
326 				x |= (u32)(*tx_buf++) << (i * 8);
327 			tegra_qspi_writel(tqspi, x, QSPI_TX_FIFO);
328 		}
329 
330 		tqspi->cur_tx_pos += written_words * tqspi->bytes_per_word;
331 	} else {
332 		unsigned int write_bytes;
333 		u8 bytes_per_word = tqspi->bytes_per_word;
334 
335 		max_n_32bit = min(tqspi->curr_dma_words, tx_empty_count);
336 		written_words = max_n_32bit;
337 		len = written_words * tqspi->bytes_per_word;
338 		if (len > t->len - tqspi->cur_pos)
339 			len = t->len - tqspi->cur_pos;
340 		write_bytes = len;
341 		for (count = 0; count < max_n_32bit; count++) {
342 			u32 x = 0;
343 
344 			for (i = 0; len && (i < min(4, bytes_per_word)); i++, len--)
345 				x |= (u32)(*tx_buf++) << (i * 8);
346 			tegra_qspi_writel(tqspi, x, QSPI_TX_FIFO);
347 		}
348 
349 		tqspi->cur_tx_pos += write_bytes;
350 	}
351 
352 	return written_words;
353 }
354 
355 static unsigned int
356 tegra_qspi_read_rx_fifo_to_client_rxbuf(struct tegra_qspi *tqspi, struct spi_transfer *t)
357 {
358 	u8 *rx_buf = (u8 *)t->rx_buf + tqspi->cur_rx_pos;
359 	unsigned int len, rx_full_count, count, i;
360 	unsigned int read_words = 0;
361 	u32 fifo_status, x;
362 
363 	fifo_status = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
364 	rx_full_count = QSPI_RX_FIFO_FULL_COUNT(fifo_status);
365 	if (tqspi->is_packed) {
366 		len = tqspi->curr_dma_words * tqspi->bytes_per_word;
367 		for (count = 0; count < rx_full_count; count++) {
368 			x = tegra_qspi_readl(tqspi, QSPI_RX_FIFO);
369 
370 			for (i = 0; len && (i < 4); i++, len--)
371 				*rx_buf++ = (x >> i * 8) & 0xff;
372 		}
373 
374 		read_words += tqspi->curr_dma_words;
375 		tqspi->cur_rx_pos += tqspi->curr_dma_words * tqspi->bytes_per_word;
376 	} else {
377 		u32 rx_mask = ((u32)1 << t->bits_per_word) - 1;
378 		u8 bytes_per_word = tqspi->bytes_per_word;
379 		unsigned int read_bytes;
380 
381 		len = rx_full_count * bytes_per_word;
382 		if (len > t->len - tqspi->cur_pos)
383 			len = t->len - tqspi->cur_pos;
384 		read_bytes = len;
385 		for (count = 0; count < rx_full_count; count++) {
386 			x = tegra_qspi_readl(tqspi, QSPI_RX_FIFO) & rx_mask;
387 
388 			for (i = 0; len && (i < bytes_per_word); i++, len--)
389 				*rx_buf++ = (x >> (i * 8)) & 0xff;
390 		}
391 
392 		read_words += rx_full_count;
393 		tqspi->cur_rx_pos += read_bytes;
394 	}
395 
396 	return read_words;
397 }
398 
399 static void
400 tegra_qspi_copy_client_txbuf_to_qspi_txbuf(struct tegra_qspi *tqspi, struct spi_transfer *t)
401 {
402 	dma_sync_single_for_cpu(tqspi->dev, tqspi->tx_dma_phys,
403 				tqspi->dma_buf_size, DMA_TO_DEVICE);
404 
405 	/*
406 	 * In packed mode, each word in FIFO may contain multiple packets
407 	 * based on bits per word. So all bytes in each FIFO word are valid.
408 	 *
409 	 * In unpacked mode, each word in FIFO contains single packet and
410 	 * based on bits per word any remaining bits in FIFO word will be
411 	 * ignored by the hardware and are invalid bits.
412 	 */
413 	if (tqspi->is_packed) {
414 		tqspi->cur_tx_pos += tqspi->curr_dma_words * tqspi->bytes_per_word;
415 	} else {
416 		u8 *tx_buf = (u8 *)t->tx_buf + tqspi->cur_tx_pos;
417 		unsigned int i, count, consume, write_bytes;
418 
419 		/*
420 		 * Fill tx_dma_buf to contain single packet in each word based
421 		 * on bits per word from SPI core tx_buf.
422 		 */
423 		consume = tqspi->curr_dma_words * tqspi->bytes_per_word;
424 		if (consume > t->len - tqspi->cur_pos)
425 			consume = t->len - tqspi->cur_pos;
426 		write_bytes = consume;
427 		for (count = 0; count < tqspi->curr_dma_words; count++) {
428 			u32 x = 0;
429 
430 			for (i = 0; consume && (i < tqspi->bytes_per_word); i++, consume--)
431 				x |= (u32)(*tx_buf++) << (i * 8);
432 			tqspi->tx_dma_buf[count] = x;
433 		}
434 
435 		tqspi->cur_tx_pos += write_bytes;
436 	}
437 
438 	dma_sync_single_for_device(tqspi->dev, tqspi->tx_dma_phys,
439 				   tqspi->dma_buf_size, DMA_TO_DEVICE);
440 }
441 
442 static void
443 tegra_qspi_copy_qspi_rxbuf_to_client_rxbuf(struct tegra_qspi *tqspi, struct spi_transfer *t)
444 {
445 	dma_sync_single_for_cpu(tqspi->dev, tqspi->rx_dma_phys,
446 				tqspi->dma_buf_size, DMA_FROM_DEVICE);
447 
448 	if (tqspi->is_packed) {
449 		tqspi->cur_rx_pos += tqspi->curr_dma_words * tqspi->bytes_per_word;
450 	} else {
451 		unsigned char *rx_buf = t->rx_buf + tqspi->cur_rx_pos;
452 		u32 rx_mask = ((u32)1 << t->bits_per_word) - 1;
453 		unsigned int i, count, consume, read_bytes;
454 
455 		/*
456 		 * Each FIFO word contains single data packet.
457 		 * Skip invalid bits in each FIFO word based on bits per word
458 		 * and align bytes while filling in SPI core rx_buf.
459 		 */
460 		consume = tqspi->curr_dma_words * tqspi->bytes_per_word;
461 		if (consume > t->len - tqspi->cur_pos)
462 			consume = t->len - tqspi->cur_pos;
463 		read_bytes = consume;
464 		for (count = 0; count < tqspi->curr_dma_words; count++) {
465 			u32 x = tqspi->rx_dma_buf[count] & rx_mask;
466 
467 			for (i = 0; consume && (i < tqspi->bytes_per_word); i++, consume--)
468 				*rx_buf++ = (x >> (i * 8)) & 0xff;
469 		}
470 
471 		tqspi->cur_rx_pos += read_bytes;
472 	}
473 
474 	dma_sync_single_for_device(tqspi->dev, tqspi->rx_dma_phys,
475 				   tqspi->dma_buf_size, DMA_FROM_DEVICE);
476 }
477 
478 static void tegra_qspi_dma_complete(void *args)
479 {
480 	struct completion *dma_complete = args;
481 
482 	complete(dma_complete);
483 }
484 
485 static int tegra_qspi_start_tx_dma(struct tegra_qspi *tqspi, struct spi_transfer *t, int len)
486 {
487 	dma_addr_t tx_dma_phys;
488 
489 	reinit_completion(&tqspi->tx_dma_complete);
490 
491 	if (tqspi->is_packed)
492 		tx_dma_phys = t->tx_dma;
493 	else
494 		tx_dma_phys = tqspi->tx_dma_phys;
495 
496 	tqspi->tx_dma_desc = dmaengine_prep_slave_single(tqspi->tx_dma_chan, tx_dma_phys,
497 							 len, DMA_MEM_TO_DEV,
498 							 DMA_PREP_INTERRUPT |  DMA_CTRL_ACK);
499 
500 	if (!tqspi->tx_dma_desc) {
501 		dev_err(tqspi->dev, "Unable to get TX descriptor\n");
502 		return -EIO;
503 	}
504 
505 	tqspi->tx_dma_desc->callback = tegra_qspi_dma_complete;
506 	tqspi->tx_dma_desc->callback_param = &tqspi->tx_dma_complete;
507 	dmaengine_submit(tqspi->tx_dma_desc);
508 	dma_async_issue_pending(tqspi->tx_dma_chan);
509 
510 	return 0;
511 }
512 
513 static int tegra_qspi_start_rx_dma(struct tegra_qspi *tqspi, struct spi_transfer *t, int len)
514 {
515 	dma_addr_t rx_dma_phys;
516 
517 	reinit_completion(&tqspi->rx_dma_complete);
518 
519 	if (tqspi->is_packed)
520 		rx_dma_phys = t->rx_dma;
521 	else
522 		rx_dma_phys = tqspi->rx_dma_phys;
523 
524 	tqspi->rx_dma_desc = dmaengine_prep_slave_single(tqspi->rx_dma_chan, rx_dma_phys,
525 							 len, DMA_DEV_TO_MEM,
526 							 DMA_PREP_INTERRUPT |  DMA_CTRL_ACK);
527 
528 	if (!tqspi->rx_dma_desc) {
529 		dev_err(tqspi->dev, "Unable to get RX descriptor\n");
530 		return -EIO;
531 	}
532 
533 	tqspi->rx_dma_desc->callback = tegra_qspi_dma_complete;
534 	tqspi->rx_dma_desc->callback_param = &tqspi->rx_dma_complete;
535 	dmaengine_submit(tqspi->rx_dma_desc);
536 	dma_async_issue_pending(tqspi->rx_dma_chan);
537 
538 	return 0;
539 }
540 
541 static int tegra_qspi_flush_fifos(struct tegra_qspi *tqspi, bool atomic)
542 {
543 	void __iomem *addr = tqspi->base + QSPI_FIFO_STATUS;
544 	u32 val;
545 
546 	val = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
547 	if ((val & QSPI_FIFO_EMPTY) == QSPI_FIFO_EMPTY)
548 		return 0;
549 
550 	val |= QSPI_RX_FIFO_FLUSH | QSPI_TX_FIFO_FLUSH;
551 	tegra_qspi_writel(tqspi, val, QSPI_FIFO_STATUS);
552 
553 	if (!atomic)
554 		return readl_relaxed_poll_timeout(addr, val,
555 						  (val & QSPI_FIFO_EMPTY) == QSPI_FIFO_EMPTY,
556 						  1000, 1000000);
557 
558 	return readl_relaxed_poll_timeout_atomic(addr, val,
559 						 (val & QSPI_FIFO_EMPTY) == QSPI_FIFO_EMPTY,
560 						 1000, 1000000);
561 }
562 
563 static void tegra_qspi_unmask_irq(struct tegra_qspi *tqspi)
564 {
565 	u32 intr_mask;
566 
567 	intr_mask = tegra_qspi_readl(tqspi, QSPI_INTR_MASK);
568 	intr_mask &= ~(QSPI_INTR_RDY_MASK | QSPI_INTR_RX_TX_FIFO_ERR);
569 	tegra_qspi_writel(tqspi, intr_mask, QSPI_INTR_MASK);
570 }
571 
572 static int tegra_qspi_dma_map_xfer(struct tegra_qspi *tqspi, struct spi_transfer *t)
573 {
574 	u8 *tx_buf = (u8 *)t->tx_buf + tqspi->cur_tx_pos;
575 	u8 *rx_buf = (u8 *)t->rx_buf + tqspi->cur_rx_pos;
576 	unsigned int len;
577 
578 	len = DIV_ROUND_UP(tqspi->curr_dma_words * tqspi->bytes_per_word, 4) * 4;
579 
580 	if (t->tx_buf) {
581 		t->tx_dma = dma_map_single(tqspi->dev, (void *)tx_buf, len, DMA_TO_DEVICE);
582 		if (dma_mapping_error(tqspi->dev, t->tx_dma))
583 			return -ENOMEM;
584 	}
585 
586 	if (t->rx_buf) {
587 		t->rx_dma = dma_map_single(tqspi->dev, (void *)rx_buf, len, DMA_FROM_DEVICE);
588 		if (dma_mapping_error(tqspi->dev, t->rx_dma)) {
589 			dma_unmap_single(tqspi->dev, t->tx_dma, len, DMA_TO_DEVICE);
590 			return -ENOMEM;
591 		}
592 	}
593 
594 	return 0;
595 }
596 
597 static void tegra_qspi_dma_unmap_xfer(struct tegra_qspi *tqspi, struct spi_transfer *t)
598 {
599 	unsigned int len;
600 
601 	len = DIV_ROUND_UP(tqspi->curr_dma_words * tqspi->bytes_per_word, 4) * 4;
602 
603 	dma_unmap_single(tqspi->dev, t->tx_dma, len, DMA_TO_DEVICE);
604 	dma_unmap_single(tqspi->dev, t->rx_dma, len, DMA_FROM_DEVICE);
605 }
606 
607 static int tegra_qspi_start_dma_based_transfer(struct tegra_qspi *tqspi, struct spi_transfer *t)
608 {
609 	struct dma_slave_config dma_sconfig = { 0 };
610 	unsigned int len;
611 	u8 dma_burst;
612 	int ret = 0;
613 	u32 val;
614 
615 	if (tqspi->is_packed) {
616 		ret = tegra_qspi_dma_map_xfer(tqspi, t);
617 		if (ret < 0)
618 			return ret;
619 	}
620 
621 	val = QSPI_DMA_BLK_SET(tqspi->curr_dma_words - 1);
622 	tegra_qspi_writel(tqspi, val, QSPI_DMA_BLK);
623 
624 	tegra_qspi_unmask_irq(tqspi);
625 
626 	if (tqspi->is_packed)
627 		len = DIV_ROUND_UP(tqspi->curr_dma_words * tqspi->bytes_per_word, 4) * 4;
628 	else
629 		len = tqspi->curr_dma_words * 4;
630 
631 	/* set attention level based on length of transfer */
632 	val = 0;
633 	if (len & 0xf) {
634 		val |= QSPI_TX_TRIG_1 | QSPI_RX_TRIG_1;
635 		dma_burst = 1;
636 	} else if (((len) >> 4) & 0x1) {
637 		val |= QSPI_TX_TRIG_4 | QSPI_RX_TRIG_4;
638 		dma_burst = 4;
639 	} else {
640 		val |= QSPI_TX_TRIG_8 | QSPI_RX_TRIG_8;
641 		dma_burst = 8;
642 	}
643 
644 	tegra_qspi_writel(tqspi, val, QSPI_DMA_CTL);
645 	tqspi->dma_control_reg = val;
646 
647 	dma_sconfig.device_fc = true;
648 	if (tqspi->cur_direction & DATA_DIR_TX) {
649 		dma_sconfig.dst_addr = tqspi->phys + QSPI_TX_FIFO;
650 		dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
651 		dma_sconfig.dst_maxburst = dma_burst;
652 		ret = dmaengine_slave_config(tqspi->tx_dma_chan, &dma_sconfig);
653 		if (ret < 0) {
654 			dev_err(tqspi->dev, "failed DMA slave config: %d\n", ret);
655 			return ret;
656 		}
657 
658 		tegra_qspi_copy_client_txbuf_to_qspi_txbuf(tqspi, t);
659 		ret = tegra_qspi_start_tx_dma(tqspi, t, len);
660 		if (ret < 0) {
661 			dev_err(tqspi->dev, "failed to starting TX DMA: %d\n", ret);
662 			return ret;
663 		}
664 	}
665 
666 	if (tqspi->cur_direction & DATA_DIR_RX) {
667 		dma_sconfig.src_addr = tqspi->phys + QSPI_RX_FIFO;
668 		dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
669 		dma_sconfig.src_maxburst = dma_burst;
670 		ret = dmaengine_slave_config(tqspi->rx_dma_chan, &dma_sconfig);
671 		if (ret < 0) {
672 			dev_err(tqspi->dev, "failed DMA slave config: %d\n", ret);
673 			return ret;
674 		}
675 
676 		dma_sync_single_for_device(tqspi->dev, tqspi->rx_dma_phys,
677 					   tqspi->dma_buf_size,
678 					   DMA_FROM_DEVICE);
679 
680 		ret = tegra_qspi_start_rx_dma(tqspi, t, len);
681 		if (ret < 0) {
682 			dev_err(tqspi->dev, "failed to start RX DMA: %d\n", ret);
683 			if (tqspi->cur_direction & DATA_DIR_TX)
684 				dmaengine_terminate_all(tqspi->tx_dma_chan);
685 			return ret;
686 		}
687 	}
688 
689 	tegra_qspi_writel(tqspi, tqspi->command1_reg, QSPI_COMMAND1);
690 
691 	tqspi->is_curr_dma_xfer = true;
692 	tqspi->dma_control_reg = val;
693 	val |= QSPI_DMA_EN;
694 	tegra_qspi_writel(tqspi, val, QSPI_DMA_CTL);
695 
696 	return ret;
697 }
698 
699 static int tegra_qspi_start_cpu_based_transfer(struct tegra_qspi *qspi, struct spi_transfer *t)
700 {
701 	u32 val;
702 	unsigned int cur_words;
703 
704 	if (qspi->cur_direction & DATA_DIR_TX)
705 		cur_words = tegra_qspi_fill_tx_fifo_from_client_txbuf(qspi, t);
706 	else
707 		cur_words = qspi->curr_dma_words;
708 
709 	val = QSPI_DMA_BLK_SET(cur_words - 1);
710 	tegra_qspi_writel(qspi, val, QSPI_DMA_BLK);
711 
712 	tegra_qspi_unmask_irq(qspi);
713 
714 	qspi->is_curr_dma_xfer = false;
715 	val = qspi->command1_reg;
716 	val |= QSPI_PIO;
717 	tegra_qspi_writel(qspi, val, QSPI_COMMAND1);
718 
719 	return 0;
720 }
721 
722 static void tegra_qspi_deinit_dma(struct tegra_qspi *tqspi)
723 {
724 	if (!tqspi->soc_data->has_dma)
725 		return;
726 
727 	if (tqspi->tx_dma_buf) {
728 		dma_free_coherent(tqspi->dev, tqspi->dma_buf_size,
729 				  tqspi->tx_dma_buf, tqspi->tx_dma_phys);
730 		tqspi->tx_dma_buf = NULL;
731 	}
732 
733 	if (tqspi->tx_dma_chan) {
734 		dma_release_channel(tqspi->tx_dma_chan);
735 		tqspi->tx_dma_chan = NULL;
736 	}
737 
738 	if (tqspi->rx_dma_buf) {
739 		dma_free_coherent(tqspi->dev, tqspi->dma_buf_size,
740 				  tqspi->rx_dma_buf, tqspi->rx_dma_phys);
741 		tqspi->rx_dma_buf = NULL;
742 	}
743 
744 	if (tqspi->rx_dma_chan) {
745 		dma_release_channel(tqspi->rx_dma_chan);
746 		tqspi->rx_dma_chan = NULL;
747 	}
748 }
749 
750 static int tegra_qspi_init_dma(struct tegra_qspi *tqspi)
751 {
752 	struct dma_chan *dma_chan;
753 	dma_addr_t dma_phys;
754 	u32 *dma_buf;
755 	int err;
756 
757 	if (!tqspi->soc_data->has_dma)
758 		return 0;
759 
760 	dma_chan = dma_request_chan(tqspi->dev, "rx");
761 	if (IS_ERR(dma_chan)) {
762 		err = PTR_ERR(dma_chan);
763 		goto err_out;
764 	}
765 
766 	tqspi->rx_dma_chan = dma_chan;
767 
768 	dma_buf = dma_alloc_coherent(tqspi->dev, tqspi->dma_buf_size, &dma_phys, GFP_KERNEL);
769 	if (!dma_buf) {
770 		err = -ENOMEM;
771 		goto err_out;
772 	}
773 
774 	tqspi->rx_dma_buf = dma_buf;
775 	tqspi->rx_dma_phys = dma_phys;
776 
777 	dma_chan = dma_request_chan(tqspi->dev, "tx");
778 	if (IS_ERR(dma_chan)) {
779 		err = PTR_ERR(dma_chan);
780 		goto err_out;
781 	}
782 
783 	tqspi->tx_dma_chan = dma_chan;
784 
785 	dma_buf = dma_alloc_coherent(tqspi->dev, tqspi->dma_buf_size, &dma_phys, GFP_KERNEL);
786 	if (!dma_buf) {
787 		err = -ENOMEM;
788 		goto err_out;
789 	}
790 
791 	tqspi->tx_dma_buf = dma_buf;
792 	tqspi->tx_dma_phys = dma_phys;
793 	tqspi->use_dma = true;
794 
795 	return 0;
796 
797 err_out:
798 	tegra_qspi_deinit_dma(tqspi);
799 
800 	if (err != -EPROBE_DEFER) {
801 		dev_err(tqspi->dev, "cannot use DMA: %d\n", err);
802 		dev_err(tqspi->dev, "falling back to PIO\n");
803 		return 0;
804 	}
805 
806 	return err;
807 }
808 
809 static u32 tegra_qspi_setup_transfer_one(struct spi_device *spi, struct spi_transfer *t,
810 					 bool is_first_of_msg)
811 {
812 	struct tegra_qspi *tqspi = spi_controller_get_devdata(spi->controller);
813 	struct tegra_qspi_client_data *cdata = spi->controller_data;
814 	u32 command1, command2, speed = t->speed_hz;
815 	u8 bits_per_word = t->bits_per_word;
816 	u32 tx_tap = 0, rx_tap = 0;
817 	int req_mode;
818 
819 	if (!has_acpi_companion(tqspi->dev) && speed != tqspi->cur_speed) {
820 		clk_set_rate(tqspi->clk, speed);
821 		tqspi->cur_speed = speed;
822 	}
823 
824 	tqspi->cur_pos = 0;
825 	tqspi->cur_rx_pos = 0;
826 	tqspi->cur_tx_pos = 0;
827 	tqspi->curr_xfer = t;
828 
829 	if (is_first_of_msg) {
830 		tegra_qspi_mask_clear_irq(tqspi);
831 
832 		command1 = tqspi->def_command1_reg;
833 		command1 |= QSPI_CS_SEL(spi_get_chipselect(spi, 0));
834 		command1 |= QSPI_BIT_LENGTH(bits_per_word - 1);
835 
836 		command1 &= ~QSPI_CONTROL_MODE_MASK;
837 		req_mode = spi->mode & 0x3;
838 		if (req_mode == SPI_MODE_3)
839 			command1 |= QSPI_CONTROL_MODE_3;
840 		else
841 			command1 |= QSPI_CONTROL_MODE_0;
842 
843 		if (spi->mode & SPI_CS_HIGH)
844 			command1 |= QSPI_CS_SW_VAL;
845 		else
846 			command1 &= ~QSPI_CS_SW_VAL;
847 		tegra_qspi_writel(tqspi, command1, QSPI_COMMAND1);
848 
849 		if (cdata && cdata->tx_clk_tap_delay)
850 			tx_tap = cdata->tx_clk_tap_delay;
851 
852 		if (cdata && cdata->rx_clk_tap_delay)
853 			rx_tap = cdata->rx_clk_tap_delay;
854 
855 		command2 = QSPI_TX_TAP_DELAY(tx_tap) | QSPI_RX_TAP_DELAY(rx_tap);
856 		if (command2 != tqspi->def_command2_reg)
857 			tegra_qspi_writel(tqspi, command2, QSPI_COMMAND2);
858 
859 	} else {
860 		command1 = tqspi->command1_reg;
861 		command1 &= ~QSPI_BIT_LENGTH(~0);
862 		command1 |= QSPI_BIT_LENGTH(bits_per_word - 1);
863 	}
864 
865 	command1 &= ~QSPI_SDR_DDR_SEL;
866 
867 	return command1;
868 }
869 
870 static int tegra_qspi_start_transfer_one(struct spi_device *spi,
871 					 struct spi_transfer *t, u32 command1)
872 {
873 	struct tegra_qspi *tqspi = spi_controller_get_devdata(spi->controller);
874 	unsigned int total_fifo_words;
875 	u8 bus_width = 0;
876 	int ret;
877 
878 	total_fifo_words = tegra_qspi_calculate_curr_xfer_param(tqspi, t);
879 
880 	command1 &= ~QSPI_PACKED;
881 	if (tqspi->is_packed)
882 		command1 |= QSPI_PACKED;
883 	tegra_qspi_writel(tqspi, command1, QSPI_COMMAND1);
884 
885 	tqspi->cur_direction = 0;
886 
887 	command1 &= ~(QSPI_TX_EN | QSPI_RX_EN);
888 	if (t->rx_buf) {
889 		command1 |= QSPI_RX_EN;
890 		tqspi->cur_direction |= DATA_DIR_RX;
891 		bus_width = t->rx_nbits;
892 	}
893 
894 	if (t->tx_buf) {
895 		command1 |= QSPI_TX_EN;
896 		tqspi->cur_direction |= DATA_DIR_TX;
897 		bus_width = t->tx_nbits;
898 	}
899 
900 	command1 &= ~QSPI_INTERFACE_WIDTH_MASK;
901 
902 	if (bus_width == SPI_NBITS_QUAD)
903 		command1 |= QSPI_INTERFACE_WIDTH_QUAD;
904 	else if (bus_width == SPI_NBITS_DUAL)
905 		command1 |= QSPI_INTERFACE_WIDTH_DUAL;
906 	else
907 		command1 |= QSPI_INTERFACE_WIDTH_SINGLE;
908 
909 	tqspi->command1_reg = command1;
910 
911 	tegra_qspi_writel(tqspi, QSPI_NUM_DUMMY_CYCLE(tqspi->dummy_cycles), QSPI_MISC_REG);
912 
913 	ret = tegra_qspi_flush_fifos(tqspi, false);
914 	if (ret < 0)
915 		return ret;
916 
917 	if (tqspi->use_dma && total_fifo_words > QSPI_FIFO_DEPTH)
918 		ret = tegra_qspi_start_dma_based_transfer(tqspi, t);
919 	else
920 		ret = tegra_qspi_start_cpu_based_transfer(tqspi, t);
921 
922 	return ret;
923 }
924 
925 static struct tegra_qspi_client_data *tegra_qspi_parse_cdata_dt(struct spi_device *spi)
926 {
927 	struct tegra_qspi_client_data *cdata;
928 	struct tegra_qspi *tqspi = spi_controller_get_devdata(spi->controller);
929 
930 	cdata = devm_kzalloc(tqspi->dev, sizeof(*cdata), GFP_KERNEL);
931 	if (!cdata)
932 		return NULL;
933 
934 	device_property_read_u32(&spi->dev, "nvidia,tx-clk-tap-delay",
935 				 &cdata->tx_clk_tap_delay);
936 	device_property_read_u32(&spi->dev, "nvidia,rx-clk-tap-delay",
937 				 &cdata->rx_clk_tap_delay);
938 
939 	return cdata;
940 }
941 
942 static int tegra_qspi_setup(struct spi_device *spi)
943 {
944 	struct tegra_qspi *tqspi = spi_controller_get_devdata(spi->controller);
945 	struct tegra_qspi_client_data *cdata = spi->controller_data;
946 	unsigned long flags;
947 	u32 val;
948 	int ret;
949 
950 	ret = pm_runtime_resume_and_get(tqspi->dev);
951 	if (ret < 0) {
952 		dev_err(tqspi->dev, "failed to get runtime PM: %d\n", ret);
953 		return ret;
954 	}
955 
956 	if (!cdata) {
957 		cdata = tegra_qspi_parse_cdata_dt(spi);
958 		spi->controller_data = cdata;
959 	}
960 	spin_lock_irqsave(&tqspi->lock, flags);
961 
962 	/* keep default cs state to inactive */
963 	val = tqspi->def_command1_reg;
964 	val |= QSPI_CS_SEL(spi_get_chipselect(spi, 0));
965 	if (spi->mode & SPI_CS_HIGH)
966 		val &= ~QSPI_CS_POL_INACTIVE(spi_get_chipselect(spi, 0));
967 	else
968 		val |= QSPI_CS_POL_INACTIVE(spi_get_chipselect(spi, 0));
969 
970 	tqspi->def_command1_reg = val;
971 	tegra_qspi_writel(tqspi, tqspi->def_command1_reg, QSPI_COMMAND1);
972 
973 	spin_unlock_irqrestore(&tqspi->lock, flags);
974 
975 	pm_runtime_put(tqspi->dev);
976 
977 	return 0;
978 }
979 
980 static void tegra_qspi_dump_regs(struct tegra_qspi *tqspi)
981 {
982 	dev_dbg(tqspi->dev, "============ QSPI REGISTER DUMP ============\n");
983 	dev_dbg(tqspi->dev, "Command1:    0x%08x | Command2:    0x%08x\n",
984 		tegra_qspi_readl(tqspi, QSPI_COMMAND1),
985 		tegra_qspi_readl(tqspi, QSPI_COMMAND2));
986 	dev_dbg(tqspi->dev, "DMA_CTL:     0x%08x | DMA_BLK:     0x%08x\n",
987 		tegra_qspi_readl(tqspi, QSPI_DMA_CTL),
988 		tegra_qspi_readl(tqspi, QSPI_DMA_BLK));
989 	dev_dbg(tqspi->dev, "INTR_MASK:  0x%08x | MISC: 0x%08x\n",
990 		tegra_qspi_readl(tqspi, QSPI_INTR_MASK),
991 		tegra_qspi_readl(tqspi, QSPI_MISC_REG));
992 	dev_dbg(tqspi->dev, "TRANS_STAT:  0x%08x | FIFO_STATUS: 0x%08x\n",
993 		tegra_qspi_readl(tqspi, QSPI_TRANS_STATUS),
994 		tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS));
995 }
996 
997 static void tegra_qspi_handle_error(struct tegra_qspi *tqspi)
998 {
999 	dev_err(tqspi->dev, "error in transfer, fifo status 0x%08x\n", tqspi->status_reg);
1000 	tegra_qspi_dump_regs(tqspi);
1001 	tegra_qspi_flush_fifos(tqspi, true);
1002 	if (device_reset(tqspi->dev) < 0)
1003 		dev_warn_once(tqspi->dev, "device reset failed\n");
1004 }
1005 
1006 static void tegra_qspi_transfer_end(struct spi_device *spi)
1007 {
1008 	struct tegra_qspi *tqspi = spi_controller_get_devdata(spi->controller);
1009 	int cs_val = (spi->mode & SPI_CS_HIGH) ? 0 : 1;
1010 
1011 	if (cs_val)
1012 		tqspi->command1_reg |= QSPI_CS_SW_VAL;
1013 	else
1014 		tqspi->command1_reg &= ~QSPI_CS_SW_VAL;
1015 	tegra_qspi_writel(tqspi, tqspi->command1_reg, QSPI_COMMAND1);
1016 	tegra_qspi_writel(tqspi, tqspi->def_command1_reg, QSPI_COMMAND1);
1017 }
1018 
1019 static u32 tegra_qspi_cmd_config(bool is_ddr, u8 bus_width, u8 len)
1020 {
1021 	u32 cmd_config = 0;
1022 
1023 	/* Extract Command configuration and value */
1024 	if (is_ddr)
1025 		cmd_config |= QSPI_COMMAND_SDR_DDR;
1026 	else
1027 		cmd_config &= ~QSPI_COMMAND_SDR_DDR;
1028 
1029 	cmd_config |= QSPI_COMMAND_X1_X2_X4(bus_width);
1030 	cmd_config |= QSPI_COMMAND_SIZE_SET((len * 8) - 1);
1031 
1032 	return cmd_config;
1033 }
1034 
1035 static u32 tegra_qspi_addr_config(bool is_ddr, u8 bus_width, u8 len)
1036 {
1037 	u32 addr_config = 0;
1038 
1039 	/* Extract Address configuration and value */
1040 	is_ddr = 0; //Only SDR mode supported
1041 	bus_width = 0; //X1 mode
1042 
1043 	if (is_ddr)
1044 		addr_config |= QSPI_ADDRESS_SDR_DDR;
1045 	else
1046 		addr_config &= ~QSPI_ADDRESS_SDR_DDR;
1047 
1048 	addr_config |= QSPI_ADDRESS_X1_X2_X4(bus_width);
1049 	addr_config |= QSPI_ADDRESS_SIZE_SET((len * 8) - 1);
1050 
1051 	return addr_config;
1052 }
1053 
1054 static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi,
1055 					struct spi_message *msg)
1056 {
1057 	bool is_first_msg = true;
1058 	struct spi_transfer *xfer;
1059 	struct spi_device *spi = msg->spi;
1060 	u8 transfer_phase = 0;
1061 	u32 cmd1 = 0, dma_ctl = 0;
1062 	int ret = 0;
1063 	u32 address_value = 0;
1064 	u32 cmd_config = 0, addr_config = 0;
1065 	u8 cmd_value = 0, val = 0;
1066 
1067 	/* Enable Combined sequence mode */
1068 	val = tegra_qspi_readl(tqspi, QSPI_GLOBAL_CONFIG);
1069 	if (spi->mode & SPI_TPM_HW_FLOW) {
1070 		if (tqspi->soc_data->supports_tpm)
1071 			val |= QSPI_TPM_WAIT_POLL_EN;
1072 		else
1073 			return -EIO;
1074 	}
1075 	val |= QSPI_CMB_SEQ_EN;
1076 	tegra_qspi_writel(tqspi, val, QSPI_GLOBAL_CONFIG);
1077 	/* Process individual transfer list */
1078 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
1079 		switch (transfer_phase) {
1080 		case CMD_TRANSFER:
1081 			/* X1 SDR mode */
1082 			cmd_config = tegra_qspi_cmd_config(false, 0,
1083 							   xfer->len);
1084 			cmd_value = *((const u8 *)(xfer->tx_buf));
1085 			break;
1086 		case ADDR_TRANSFER:
1087 			/* X1 SDR mode */
1088 			addr_config = tegra_qspi_addr_config(false, 0,
1089 							     xfer->len);
1090 			address_value = *((const u32 *)(xfer->tx_buf));
1091 			break;
1092 		case DATA_TRANSFER:
1093 			/* Program Command, Address value in register */
1094 			tegra_qspi_writel(tqspi, cmd_value, QSPI_CMB_SEQ_CMD);
1095 			tegra_qspi_writel(tqspi, address_value,
1096 					  QSPI_CMB_SEQ_ADDR);
1097 			/* Program Command and Address config in register */
1098 			tegra_qspi_writel(tqspi, cmd_config,
1099 					  QSPI_CMB_SEQ_CMD_CFG);
1100 			tegra_qspi_writel(tqspi, addr_config,
1101 					  QSPI_CMB_SEQ_ADDR_CFG);
1102 
1103 			reinit_completion(&tqspi->xfer_completion);
1104 			cmd1 = tegra_qspi_setup_transfer_one(spi, xfer,
1105 							     is_first_msg);
1106 			ret = tegra_qspi_start_transfer_one(spi, xfer,
1107 							    cmd1);
1108 
1109 			if (ret < 0) {
1110 				dev_err(tqspi->dev, "Failed to start transfer-one: %d\n",
1111 					ret);
1112 				return ret;
1113 			}
1114 
1115 			is_first_msg = false;
1116 			ret = wait_for_completion_timeout
1117 					(&tqspi->xfer_completion,
1118 					QSPI_DMA_TIMEOUT);
1119 
1120 			if (WARN_ON(ret == 0)) {
1121 				dev_err(tqspi->dev, "QSPI Transfer failed with timeout: %d\n",
1122 					ret);
1123 				if (tqspi->is_curr_dma_xfer &&
1124 				    (tqspi->cur_direction & DATA_DIR_TX))
1125 					dmaengine_terminate_all
1126 						(tqspi->tx_dma_chan);
1127 
1128 				if (tqspi->is_curr_dma_xfer &&
1129 				    (tqspi->cur_direction & DATA_DIR_RX))
1130 					dmaengine_terminate_all
1131 						(tqspi->rx_dma_chan);
1132 
1133 				/* Abort transfer by resetting pio/dma bit */
1134 				if (!tqspi->is_curr_dma_xfer) {
1135 					cmd1 = tegra_qspi_readl
1136 							(tqspi,
1137 							 QSPI_COMMAND1);
1138 					cmd1 &= ~QSPI_PIO;
1139 					tegra_qspi_writel
1140 							(tqspi, cmd1,
1141 							 QSPI_COMMAND1);
1142 				} else {
1143 					dma_ctl = tegra_qspi_readl
1144 							(tqspi,
1145 							 QSPI_DMA_CTL);
1146 					dma_ctl &= ~QSPI_DMA_EN;
1147 					tegra_qspi_writel(tqspi, dma_ctl,
1148 							  QSPI_DMA_CTL);
1149 				}
1150 
1151 				/* Reset controller if timeout happens */
1152 				if (device_reset(tqspi->dev) < 0)
1153 					dev_warn_once(tqspi->dev,
1154 						      "device reset failed\n");
1155 				ret = -EIO;
1156 				goto exit;
1157 			}
1158 
1159 			if (tqspi->tx_status ||  tqspi->rx_status) {
1160 				dev_err(tqspi->dev, "QSPI Transfer failed\n");
1161 				tqspi->tx_status = 0;
1162 				tqspi->rx_status = 0;
1163 				ret = -EIO;
1164 				goto exit;
1165 			}
1166 			if (!xfer->cs_change) {
1167 				tegra_qspi_transfer_end(spi);
1168 				spi_transfer_delay_exec(xfer);
1169 			}
1170 			break;
1171 		default:
1172 			ret = -EINVAL;
1173 			goto exit;
1174 		}
1175 		msg->actual_length += xfer->len;
1176 		transfer_phase++;
1177 	}
1178 	ret = 0;
1179 
1180 exit:
1181 	msg->status = ret;
1182 	if (ret < 0) {
1183 		tegra_qspi_transfer_end(spi);
1184 		spi_transfer_delay_exec(xfer);
1185 	}
1186 
1187 	return ret;
1188 }
1189 
1190 static int tegra_qspi_non_combined_seq_xfer(struct tegra_qspi *tqspi,
1191 					    struct spi_message *msg)
1192 {
1193 	struct spi_device *spi = msg->spi;
1194 	struct spi_transfer *transfer;
1195 	bool is_first_msg = true;
1196 	int ret = 0, val = 0;
1197 
1198 	msg->status = 0;
1199 	msg->actual_length = 0;
1200 	tqspi->tx_status = 0;
1201 	tqspi->rx_status = 0;
1202 
1203 	/* Disable Combined sequence mode */
1204 	val = tegra_qspi_readl(tqspi, QSPI_GLOBAL_CONFIG);
1205 	val &= ~QSPI_CMB_SEQ_EN;
1206 	if (tqspi->soc_data->supports_tpm)
1207 		val &= ~QSPI_TPM_WAIT_POLL_EN;
1208 	tegra_qspi_writel(tqspi, val, QSPI_GLOBAL_CONFIG);
1209 	list_for_each_entry(transfer, &msg->transfers, transfer_list) {
1210 		struct spi_transfer *xfer = transfer;
1211 		u8 dummy_bytes = 0;
1212 		u32 cmd1;
1213 
1214 		tqspi->dummy_cycles = 0;
1215 		/*
1216 		 * Tegra QSPI hardware supports dummy bytes transfer after actual transfer
1217 		 * bytes based on programmed dummy clock cycles in the QSPI_MISC register.
1218 		 * So, check if the next transfer is dummy data transfer and program dummy
1219 		 * clock cycles along with the current transfer and skip next transfer.
1220 		 */
1221 		if (!list_is_last(&xfer->transfer_list, &msg->transfers)) {
1222 			struct spi_transfer *next_xfer;
1223 
1224 			next_xfer = list_next_entry(xfer, transfer_list);
1225 			if (next_xfer->dummy_data) {
1226 				u32 dummy_cycles = next_xfer->len * 8 / next_xfer->tx_nbits;
1227 
1228 				if (dummy_cycles <= QSPI_DUMMY_CYCLES_MAX) {
1229 					tqspi->dummy_cycles = dummy_cycles;
1230 					dummy_bytes = next_xfer->len;
1231 					transfer = next_xfer;
1232 				}
1233 			}
1234 		}
1235 
1236 		reinit_completion(&tqspi->xfer_completion);
1237 
1238 		cmd1 = tegra_qspi_setup_transfer_one(spi, xfer, is_first_msg);
1239 
1240 		ret = tegra_qspi_start_transfer_one(spi, xfer, cmd1);
1241 		if (ret < 0) {
1242 			dev_err(tqspi->dev, "failed to start transfer: %d\n", ret);
1243 			goto complete_xfer;
1244 		}
1245 
1246 		ret = wait_for_completion_timeout(&tqspi->xfer_completion,
1247 						  QSPI_DMA_TIMEOUT);
1248 		if (WARN_ON(ret == 0)) {
1249 			dev_err(tqspi->dev, "transfer timeout\n");
1250 			if (tqspi->is_curr_dma_xfer && (tqspi->cur_direction & DATA_DIR_TX))
1251 				dmaengine_terminate_all(tqspi->tx_dma_chan);
1252 			if (tqspi->is_curr_dma_xfer && (tqspi->cur_direction & DATA_DIR_RX))
1253 				dmaengine_terminate_all(tqspi->rx_dma_chan);
1254 			tegra_qspi_handle_error(tqspi);
1255 			ret = -EIO;
1256 			goto complete_xfer;
1257 		}
1258 
1259 		if (tqspi->tx_status ||  tqspi->rx_status) {
1260 			tegra_qspi_handle_error(tqspi);
1261 			ret = -EIO;
1262 			goto complete_xfer;
1263 		}
1264 
1265 		msg->actual_length += xfer->len + dummy_bytes;
1266 
1267 complete_xfer:
1268 		if (ret < 0) {
1269 			tegra_qspi_transfer_end(spi);
1270 			spi_transfer_delay_exec(xfer);
1271 			goto exit;
1272 		}
1273 
1274 		if (list_is_last(&xfer->transfer_list, &msg->transfers)) {
1275 			/* de-activate CS after last transfer only when cs_change is not set */
1276 			if (!xfer->cs_change) {
1277 				tegra_qspi_transfer_end(spi);
1278 				spi_transfer_delay_exec(xfer);
1279 			}
1280 		} else if (xfer->cs_change) {
1281 			 /* de-activated CS between the transfers only when cs_change is set */
1282 			tegra_qspi_transfer_end(spi);
1283 			spi_transfer_delay_exec(xfer);
1284 		}
1285 	}
1286 
1287 	ret = 0;
1288 exit:
1289 	msg->status = ret;
1290 
1291 	return ret;
1292 }
1293 
1294 static bool tegra_qspi_validate_cmb_seq(struct tegra_qspi *tqspi,
1295 					struct spi_message *msg)
1296 {
1297 	int transfer_count = 0;
1298 	struct spi_transfer *xfer;
1299 
1300 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
1301 		transfer_count++;
1302 	}
1303 	if (!tqspi->soc_data->cmb_xfer_capable || transfer_count != 3)
1304 		return false;
1305 	xfer = list_first_entry(&msg->transfers, typeof(*xfer),
1306 				transfer_list);
1307 	if (xfer->len > 2)
1308 		return false;
1309 	xfer = list_next_entry(xfer, transfer_list);
1310 	if (xfer->len > 4 || xfer->len < 3)
1311 		return false;
1312 	xfer = list_next_entry(xfer, transfer_list);
1313 	if (!tqspi->soc_data->has_dma && xfer->len > (QSPI_FIFO_DEPTH << 2))
1314 		return false;
1315 
1316 	return true;
1317 }
1318 
1319 static int tegra_qspi_transfer_one_message(struct spi_controller *host,
1320 					   struct spi_message *msg)
1321 {
1322 	struct tegra_qspi *tqspi = spi_controller_get_devdata(host);
1323 	int ret;
1324 
1325 	if (tegra_qspi_validate_cmb_seq(tqspi, msg))
1326 		ret = tegra_qspi_combined_seq_xfer(tqspi, msg);
1327 	else
1328 		ret = tegra_qspi_non_combined_seq_xfer(tqspi, msg);
1329 
1330 	spi_finalize_current_message(host);
1331 
1332 	return ret;
1333 }
1334 
1335 static irqreturn_t handle_cpu_based_xfer(struct tegra_qspi *tqspi)
1336 {
1337 	struct spi_transfer *t = tqspi->curr_xfer;
1338 	unsigned long flags;
1339 
1340 	spin_lock_irqsave(&tqspi->lock, flags);
1341 
1342 	if (tqspi->tx_status ||  tqspi->rx_status) {
1343 		tegra_qspi_handle_error(tqspi);
1344 		complete(&tqspi->xfer_completion);
1345 		goto exit;
1346 	}
1347 
1348 	if (tqspi->cur_direction & DATA_DIR_RX)
1349 		tegra_qspi_read_rx_fifo_to_client_rxbuf(tqspi, t);
1350 
1351 	if (tqspi->cur_direction & DATA_DIR_TX)
1352 		tqspi->cur_pos = tqspi->cur_tx_pos;
1353 	else
1354 		tqspi->cur_pos = tqspi->cur_rx_pos;
1355 
1356 	if (tqspi->cur_pos == t->len) {
1357 		complete(&tqspi->xfer_completion);
1358 		goto exit;
1359 	}
1360 
1361 	tegra_qspi_calculate_curr_xfer_param(tqspi, t);
1362 	tegra_qspi_start_cpu_based_transfer(tqspi, t);
1363 exit:
1364 	spin_unlock_irqrestore(&tqspi->lock, flags);
1365 	return IRQ_HANDLED;
1366 }
1367 
1368 static irqreturn_t handle_dma_based_xfer(struct tegra_qspi *tqspi)
1369 {
1370 	struct spi_transfer *t = tqspi->curr_xfer;
1371 	unsigned int total_fifo_words;
1372 	unsigned long flags;
1373 	long wait_status;
1374 	int err = 0;
1375 
1376 	if (tqspi->cur_direction & DATA_DIR_TX) {
1377 		if (tqspi->tx_status) {
1378 			dmaengine_terminate_all(tqspi->tx_dma_chan);
1379 			err += 1;
1380 		} else {
1381 			wait_status = wait_for_completion_interruptible_timeout(
1382 				&tqspi->tx_dma_complete, QSPI_DMA_TIMEOUT);
1383 			if (wait_status <= 0) {
1384 				dmaengine_terminate_all(tqspi->tx_dma_chan);
1385 				dev_err(tqspi->dev, "failed TX DMA transfer\n");
1386 				err += 1;
1387 			}
1388 		}
1389 	}
1390 
1391 	if (tqspi->cur_direction & DATA_DIR_RX) {
1392 		if (tqspi->rx_status) {
1393 			dmaengine_terminate_all(tqspi->rx_dma_chan);
1394 			err += 2;
1395 		} else {
1396 			wait_status = wait_for_completion_interruptible_timeout(
1397 				&tqspi->rx_dma_complete, QSPI_DMA_TIMEOUT);
1398 			if (wait_status <= 0) {
1399 				dmaengine_terminate_all(tqspi->rx_dma_chan);
1400 				dev_err(tqspi->dev, "failed RX DMA transfer\n");
1401 				err += 2;
1402 			}
1403 		}
1404 	}
1405 
1406 	spin_lock_irqsave(&tqspi->lock, flags);
1407 
1408 	if (err) {
1409 		tegra_qspi_dma_unmap_xfer(tqspi, t);
1410 		tegra_qspi_handle_error(tqspi);
1411 		complete(&tqspi->xfer_completion);
1412 		goto exit;
1413 	}
1414 
1415 	if (tqspi->cur_direction & DATA_DIR_RX)
1416 		tegra_qspi_copy_qspi_rxbuf_to_client_rxbuf(tqspi, t);
1417 
1418 	if (tqspi->cur_direction & DATA_DIR_TX)
1419 		tqspi->cur_pos = tqspi->cur_tx_pos;
1420 	else
1421 		tqspi->cur_pos = tqspi->cur_rx_pos;
1422 
1423 	if (tqspi->cur_pos == t->len) {
1424 		tegra_qspi_dma_unmap_xfer(tqspi, t);
1425 		complete(&tqspi->xfer_completion);
1426 		goto exit;
1427 	}
1428 
1429 	tegra_qspi_dma_unmap_xfer(tqspi, t);
1430 
1431 	/* continue transfer in current message */
1432 	total_fifo_words = tegra_qspi_calculate_curr_xfer_param(tqspi, t);
1433 	if (total_fifo_words > QSPI_FIFO_DEPTH)
1434 		err = tegra_qspi_start_dma_based_transfer(tqspi, t);
1435 	else
1436 		err = tegra_qspi_start_cpu_based_transfer(tqspi, t);
1437 
1438 exit:
1439 	spin_unlock_irqrestore(&tqspi->lock, flags);
1440 	return IRQ_HANDLED;
1441 }
1442 
1443 static irqreturn_t tegra_qspi_isr_thread(int irq, void *context_data)
1444 {
1445 	struct tegra_qspi *tqspi = context_data;
1446 
1447 	tqspi->status_reg = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
1448 
1449 	if (tqspi->cur_direction & DATA_DIR_TX)
1450 		tqspi->tx_status = tqspi->status_reg & (QSPI_TX_FIFO_UNF | QSPI_TX_FIFO_OVF);
1451 
1452 	if (tqspi->cur_direction & DATA_DIR_RX)
1453 		tqspi->rx_status = tqspi->status_reg & (QSPI_RX_FIFO_OVF | QSPI_RX_FIFO_UNF);
1454 
1455 	tegra_qspi_mask_clear_irq(tqspi);
1456 
1457 	if (!tqspi->is_curr_dma_xfer)
1458 		return handle_cpu_based_xfer(tqspi);
1459 
1460 	return handle_dma_based_xfer(tqspi);
1461 }
1462 
1463 static struct tegra_qspi_soc_data tegra210_qspi_soc_data = {
1464 	.has_dma = true,
1465 	.cmb_xfer_capable = false,
1466 	.supports_tpm = false,
1467 	.cs_count = 1,
1468 };
1469 
1470 static struct tegra_qspi_soc_data tegra186_qspi_soc_data = {
1471 	.has_dma = true,
1472 	.cmb_xfer_capable = true,
1473 	.supports_tpm = false,
1474 	.cs_count = 1,
1475 };
1476 
1477 static struct tegra_qspi_soc_data tegra234_qspi_soc_data = {
1478 	.has_dma = false,
1479 	.cmb_xfer_capable = true,
1480 	.supports_tpm = true,
1481 	.cs_count = 1,
1482 };
1483 
1484 static struct tegra_qspi_soc_data tegra241_qspi_soc_data = {
1485 	.has_dma = false,
1486 	.cmb_xfer_capable = true,
1487 	.supports_tpm = true,
1488 	.cs_count = 4,
1489 };
1490 
1491 static const struct of_device_id tegra_qspi_of_match[] = {
1492 	{
1493 		.compatible = "nvidia,tegra210-qspi",
1494 		.data	    = &tegra210_qspi_soc_data,
1495 	}, {
1496 		.compatible = "nvidia,tegra186-qspi",
1497 		.data	    = &tegra186_qspi_soc_data,
1498 	}, {
1499 		.compatible = "nvidia,tegra194-qspi",
1500 		.data	    = &tegra186_qspi_soc_data,
1501 	}, {
1502 		.compatible = "nvidia,tegra234-qspi",
1503 		.data	    = &tegra234_qspi_soc_data,
1504 	}, {
1505 		.compatible = "nvidia,tegra241-qspi",
1506 		.data	    = &tegra241_qspi_soc_data,
1507 	},
1508 	{}
1509 };
1510 
1511 MODULE_DEVICE_TABLE(of, tegra_qspi_of_match);
1512 
1513 #ifdef CONFIG_ACPI
1514 static const struct acpi_device_id tegra_qspi_acpi_match[] = {
1515 	{
1516 		.id = "NVDA1213",
1517 		.driver_data = (kernel_ulong_t)&tegra210_qspi_soc_data,
1518 	}, {
1519 		.id = "NVDA1313",
1520 		.driver_data = (kernel_ulong_t)&tegra186_qspi_soc_data,
1521 	}, {
1522 		.id = "NVDA1413",
1523 		.driver_data = (kernel_ulong_t)&tegra234_qspi_soc_data,
1524 	}, {
1525 		.id = "NVDA1513",
1526 		.driver_data = (kernel_ulong_t)&tegra241_qspi_soc_data,
1527 	},
1528 	{}
1529 };
1530 
1531 MODULE_DEVICE_TABLE(acpi, tegra_qspi_acpi_match);
1532 #endif
1533 
1534 static int tegra_qspi_probe(struct platform_device *pdev)
1535 {
1536 	struct spi_controller	*host;
1537 	struct tegra_qspi	*tqspi;
1538 	struct resource		*r;
1539 	int ret, qspi_irq;
1540 	int bus_num;
1541 
1542 	host = devm_spi_alloc_host(&pdev->dev, sizeof(*tqspi));
1543 	if (!host)
1544 		return -ENOMEM;
1545 
1546 	platform_set_drvdata(pdev, host);
1547 	tqspi = spi_controller_get_devdata(host);
1548 
1549 	host->mode_bits = SPI_MODE_0 | SPI_MODE_3 | SPI_CS_HIGH |
1550 			  SPI_TX_DUAL | SPI_RX_DUAL | SPI_TX_QUAD | SPI_RX_QUAD;
1551 	host->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
1552 	host->flags = SPI_CONTROLLER_HALF_DUPLEX;
1553 	host->setup = tegra_qspi_setup;
1554 	host->transfer_one_message = tegra_qspi_transfer_one_message;
1555 	host->num_chipselect = 1;
1556 	host->auto_runtime_pm = true;
1557 
1558 	bus_num = of_alias_get_id(pdev->dev.of_node, "spi");
1559 	if (bus_num >= 0)
1560 		host->bus_num = bus_num;
1561 
1562 	tqspi->host = host;
1563 	tqspi->dev = &pdev->dev;
1564 	spin_lock_init(&tqspi->lock);
1565 
1566 	tqspi->soc_data = device_get_match_data(&pdev->dev);
1567 	host->num_chipselect = tqspi->soc_data->cs_count;
1568 	tqspi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &r);
1569 	if (IS_ERR(tqspi->base))
1570 		return PTR_ERR(tqspi->base);
1571 
1572 	tqspi->phys = r->start;
1573 	qspi_irq = platform_get_irq(pdev, 0);
1574 	if (qspi_irq < 0)
1575 		return qspi_irq;
1576 	tqspi->irq = qspi_irq;
1577 
1578 	if (!has_acpi_companion(tqspi->dev)) {
1579 		tqspi->clk = devm_clk_get(&pdev->dev, "qspi");
1580 		if (IS_ERR(tqspi->clk)) {
1581 			ret = PTR_ERR(tqspi->clk);
1582 			dev_err(&pdev->dev, "failed to get clock: %d\n", ret);
1583 			return ret;
1584 		}
1585 
1586 	}
1587 
1588 	tqspi->max_buf_size = QSPI_FIFO_DEPTH << 2;
1589 	tqspi->dma_buf_size = DEFAULT_QSPI_DMA_BUF_LEN;
1590 
1591 	ret = tegra_qspi_init_dma(tqspi);
1592 	if (ret < 0)
1593 		return ret;
1594 
1595 	if (tqspi->use_dma)
1596 		tqspi->max_buf_size = tqspi->dma_buf_size;
1597 
1598 	init_completion(&tqspi->tx_dma_complete);
1599 	init_completion(&tqspi->rx_dma_complete);
1600 	init_completion(&tqspi->xfer_completion);
1601 
1602 	pm_runtime_enable(&pdev->dev);
1603 	ret = pm_runtime_resume_and_get(&pdev->dev);
1604 	if (ret < 0) {
1605 		dev_err(&pdev->dev, "failed to get runtime PM: %d\n", ret);
1606 		goto exit_pm_disable;
1607 	}
1608 
1609 	if (device_reset(tqspi->dev) < 0)
1610 		dev_warn_once(tqspi->dev, "device reset failed\n");
1611 
1612 	tqspi->def_command1_reg = QSPI_M_S | QSPI_CS_SW_HW |  QSPI_CS_SW_VAL;
1613 	tegra_qspi_writel(tqspi, tqspi->def_command1_reg, QSPI_COMMAND1);
1614 	tqspi->spi_cs_timing1 = tegra_qspi_readl(tqspi, QSPI_CS_TIMING1);
1615 	tqspi->spi_cs_timing2 = tegra_qspi_readl(tqspi, QSPI_CS_TIMING2);
1616 	tqspi->def_command2_reg = tegra_qspi_readl(tqspi, QSPI_COMMAND2);
1617 
1618 	pm_runtime_put(&pdev->dev);
1619 
1620 	ret = request_threaded_irq(tqspi->irq, NULL,
1621 				   tegra_qspi_isr_thread, IRQF_ONESHOT,
1622 				   dev_name(&pdev->dev), tqspi);
1623 	if (ret < 0) {
1624 		dev_err(&pdev->dev, "failed to request IRQ#%u: %d\n", tqspi->irq, ret);
1625 		goto exit_pm_disable;
1626 	}
1627 
1628 	host->dev.of_node = pdev->dev.of_node;
1629 	ret = spi_register_controller(host);
1630 	if (ret < 0) {
1631 		dev_err(&pdev->dev, "failed to register host: %d\n", ret);
1632 		goto exit_free_irq;
1633 	}
1634 
1635 	return 0;
1636 
1637 exit_free_irq:
1638 	free_irq(qspi_irq, tqspi);
1639 exit_pm_disable:
1640 	pm_runtime_force_suspend(&pdev->dev);
1641 	tegra_qspi_deinit_dma(tqspi);
1642 	return ret;
1643 }
1644 
1645 static void tegra_qspi_remove(struct platform_device *pdev)
1646 {
1647 	struct spi_controller *host = platform_get_drvdata(pdev);
1648 	struct tegra_qspi *tqspi = spi_controller_get_devdata(host);
1649 
1650 	spi_unregister_controller(host);
1651 	free_irq(tqspi->irq, tqspi);
1652 	pm_runtime_force_suspend(&pdev->dev);
1653 	tegra_qspi_deinit_dma(tqspi);
1654 }
1655 
1656 static int __maybe_unused tegra_qspi_suspend(struct device *dev)
1657 {
1658 	struct spi_controller *host = dev_get_drvdata(dev);
1659 
1660 	return spi_controller_suspend(host);
1661 }
1662 
1663 static int __maybe_unused tegra_qspi_resume(struct device *dev)
1664 {
1665 	struct spi_controller *host = dev_get_drvdata(dev);
1666 	struct tegra_qspi *tqspi = spi_controller_get_devdata(host);
1667 	int ret;
1668 
1669 	ret = pm_runtime_resume_and_get(dev);
1670 	if (ret < 0) {
1671 		dev_err(dev, "failed to get runtime PM: %d\n", ret);
1672 		return ret;
1673 	}
1674 
1675 	tegra_qspi_writel(tqspi, tqspi->command1_reg, QSPI_COMMAND1);
1676 	tegra_qspi_writel(tqspi, tqspi->def_command2_reg, QSPI_COMMAND2);
1677 	pm_runtime_put(dev);
1678 
1679 	return spi_controller_resume(host);
1680 }
1681 
1682 static int __maybe_unused tegra_qspi_runtime_suspend(struct device *dev)
1683 {
1684 	struct spi_controller *host = dev_get_drvdata(dev);
1685 	struct tegra_qspi *tqspi = spi_controller_get_devdata(host);
1686 
1687 	/* Runtime pm disabled with ACPI */
1688 	if (has_acpi_companion(tqspi->dev))
1689 		return 0;
1690 	/* flush all write which are in PPSB queue by reading back */
1691 	tegra_qspi_readl(tqspi, QSPI_COMMAND1);
1692 
1693 	clk_disable_unprepare(tqspi->clk);
1694 
1695 	return 0;
1696 }
1697 
1698 static int __maybe_unused tegra_qspi_runtime_resume(struct device *dev)
1699 {
1700 	struct spi_controller *host = dev_get_drvdata(dev);
1701 	struct tegra_qspi *tqspi = spi_controller_get_devdata(host);
1702 	int ret;
1703 
1704 	/* Runtime pm disabled with ACPI */
1705 	if (has_acpi_companion(tqspi->dev))
1706 		return 0;
1707 	ret = clk_prepare_enable(tqspi->clk);
1708 	if (ret < 0)
1709 		dev_err(tqspi->dev, "failed to enable clock: %d\n", ret);
1710 
1711 	return ret;
1712 }
1713 
1714 static const struct dev_pm_ops tegra_qspi_pm_ops = {
1715 	SET_RUNTIME_PM_OPS(tegra_qspi_runtime_suspend, tegra_qspi_runtime_resume, NULL)
1716 	SET_SYSTEM_SLEEP_PM_OPS(tegra_qspi_suspend, tegra_qspi_resume)
1717 };
1718 
1719 static struct platform_driver tegra_qspi_driver = {
1720 	.driver = {
1721 		.name		= "tegra-qspi",
1722 		.pm		= &tegra_qspi_pm_ops,
1723 		.of_match_table	= tegra_qspi_of_match,
1724 		.acpi_match_table = ACPI_PTR(tegra_qspi_acpi_match),
1725 	},
1726 	.probe =	tegra_qspi_probe,
1727 	.remove =	tegra_qspi_remove,
1728 };
1729 module_platform_driver(tegra_qspi_driver);
1730 
1731 MODULE_ALIAS("platform:qspi-tegra");
1732 MODULE_DESCRIPTION("NVIDIA Tegra QSPI Controller Driver");
1733 MODULE_AUTHOR("Sowjanya Komatineni <skomatineni@nvidia.com>");
1734 MODULE_LICENSE("GPL v2");
1735