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  1// SPDX-License-Identifier: GPL-2.0
  2//
  3// Mediatek SPI NOR controller driver
  4//
  5// Copyright (C) 2020 Chuanhong Guo <gch981213@gmail.com>
  6
  7#include <linux/bits.h>
  8#include <linux/clk.h>
  9#include <linux/completion.h>
 10#include <linux/dma-mapping.h>
 11#include <linux/interrupt.h>
 12#include <linux/io.h>
 13#include <linux/iopoll.h>
 14#include <linux/kernel.h>
 15#include <linux/module.h>
 16#include <linux/of_device.h>
 17#include <linux/spi/spi.h>
 18#include <linux/spi/spi-mem.h>
 19#include <linux/string.h>
 20
 21#define DRIVER_NAME "mtk-spi-nor"
 22
 23#define MTK_NOR_REG_CMD			0x00
 24#define MTK_NOR_CMD_WRITE		BIT(4)
 25#define MTK_NOR_CMD_PROGRAM		BIT(2)
 26#define MTK_NOR_CMD_READ		BIT(0)
 27#define MTK_NOR_CMD_MASK		GENMASK(5, 0)
 28
 29#define MTK_NOR_REG_PRG_CNT		0x04
 30#define MTK_NOR_REG_RDATA		0x0c
 31
 32#define MTK_NOR_REG_RADR0		0x10
 33#define MTK_NOR_REG_RADR(n)		(MTK_NOR_REG_RADR0 + 4 * (n))
 34#define MTK_NOR_REG_RADR3		0xc8
 35
 36#define MTK_NOR_REG_WDATA		0x1c
 37
 38#define MTK_NOR_REG_PRGDATA0		0x20
 39#define MTK_NOR_REG_PRGDATA(n)		(MTK_NOR_REG_PRGDATA0 + 4 * (n))
 40#define MTK_NOR_REG_PRGDATA_MAX		5
 41
 42#define MTK_NOR_REG_SHIFT0		0x38
 43#define MTK_NOR_REG_SHIFT(n)		(MTK_NOR_REG_SHIFT0 + 4 * (n))
 44#define MTK_NOR_REG_SHIFT_MAX		9
 45
 46#define MTK_NOR_REG_CFG1		0x60
 47#define MTK_NOR_FAST_READ		BIT(0)
 48
 49#define MTK_NOR_REG_CFG2		0x64
 50#define MTK_NOR_WR_CUSTOM_OP_EN		BIT(4)
 51#define MTK_NOR_WR_BUF_EN		BIT(0)
 52
 53#define MTK_NOR_REG_PP_DATA		0x98
 54
 55#define MTK_NOR_REG_IRQ_STAT		0xa8
 56#define MTK_NOR_REG_IRQ_EN		0xac
 57#define MTK_NOR_IRQ_DMA			BIT(7)
 58#define MTK_NOR_IRQ_MASK		GENMASK(7, 0)
 59
 60#define MTK_NOR_REG_CFG3		0xb4
 61#define MTK_NOR_DISABLE_WREN		BIT(7)
 62#define MTK_NOR_DISABLE_SR_POLL		BIT(5)
 63
 64#define MTK_NOR_REG_WP			0xc4
 65#define MTK_NOR_ENABLE_SF_CMD		0x30
 66
 67#define MTK_NOR_REG_BUSCFG		0xcc
 68#define MTK_NOR_4B_ADDR			BIT(4)
 69#define MTK_NOR_QUAD_ADDR		BIT(3)
 70#define MTK_NOR_QUAD_READ		BIT(2)
 71#define MTK_NOR_DUAL_ADDR		BIT(1)
 72#define MTK_NOR_DUAL_READ		BIT(0)
 73#define MTK_NOR_BUS_MODE_MASK		GENMASK(4, 0)
 74
 75#define MTK_NOR_REG_DMA_CTL		0x718
 76#define MTK_NOR_DMA_START		BIT(0)
 77
 78#define MTK_NOR_REG_DMA_FADR		0x71c
 79#define MTK_NOR_REG_DMA_DADR		0x720
 80#define MTK_NOR_REG_DMA_END_DADR	0x724
 81
 82#define MTK_NOR_PRG_MAX_SIZE		6
 83// Reading DMA src/dst addresses have to be 16-byte aligned
 84#define MTK_NOR_DMA_ALIGN		16
 85#define MTK_NOR_DMA_ALIGN_MASK		(MTK_NOR_DMA_ALIGN - 1)
 86// and we allocate a bounce buffer if destination address isn't aligned.
 87#define MTK_NOR_BOUNCE_BUF_SIZE		PAGE_SIZE
 88
 89// Buffered page program can do one 128-byte transfer
 90#define MTK_NOR_PP_SIZE			128
 91
 92#define CLK_TO_US(sp, clkcnt)		((clkcnt) * 1000000 / sp->spi_freq)
 93
 94struct mtk_nor {
 95	struct spi_controller *ctlr;
 96	struct device *dev;
 97	void __iomem *base;
 98	u8 *buffer;
 99	struct clk *spi_clk;
100	struct clk *ctlr_clk;
101	unsigned int spi_freq;
102	bool wbuf_en;
103	bool has_irq;
104	struct completion op_done;
105};
106
107static inline void mtk_nor_rmw(struct mtk_nor *sp, u32 reg, u32 set, u32 clr)
108{
109	u32 val = readl(sp->base + reg);
110
111	val &= ~clr;
112	val |= set;
113	writel(val, sp->base + reg);
114}
115
116static inline int mtk_nor_cmd_exec(struct mtk_nor *sp, u32 cmd, ulong clk)
117{
118	ulong delay = CLK_TO_US(sp, clk);
119	u32 reg;
120	int ret;
121
122	writel(cmd, sp->base + MTK_NOR_REG_CMD);
123	ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CMD, reg, !(reg & cmd),
124				 delay / 3, (delay + 1) * 200);
125	if (ret < 0)
126		dev_err(sp->dev, "command %u timeout.\n", cmd);
127	return ret;
128}
129
130static void mtk_nor_set_addr(struct mtk_nor *sp, const struct spi_mem_op *op)
131{
132	u32 addr = op->addr.val;
133	int i;
134
135	for (i = 0; i < 3; i++) {
136		writeb(addr & 0xff, sp->base + MTK_NOR_REG_RADR(i));
137		addr >>= 8;
138	}
139	if (op->addr.nbytes == 4) {
140		writeb(addr & 0xff, sp->base + MTK_NOR_REG_RADR3);
141		mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, MTK_NOR_4B_ADDR, 0);
142	} else {
143		mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, 0, MTK_NOR_4B_ADDR);
144	}
145}
146
147static bool mtk_nor_match_read(const struct spi_mem_op *op)
148{
149	int dummy = 0;
150
151	if (op->dummy.buswidth)
152		dummy = op->dummy.nbytes * BITS_PER_BYTE / op->dummy.buswidth;
153
154	if ((op->data.buswidth == 2) || (op->data.buswidth == 4)) {
155		if (op->addr.buswidth == 1)
156			return dummy == 8;
157		else if (op->addr.buswidth == 2)
158			return dummy == 4;
159		else if (op->addr.buswidth == 4)
160			return dummy == 6;
161	} else if ((op->addr.buswidth == 1) && (op->data.buswidth == 1)) {
162		if (op->cmd.opcode == 0x03)
163			return dummy == 0;
164		else if (op->cmd.opcode == 0x0b)
165			return dummy == 8;
166	}
167	return false;
168}
169
170static int mtk_nor_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
171{
172	size_t len;
173
174	if (!op->data.nbytes)
175		return 0;
176
177	if ((op->addr.nbytes == 3) || (op->addr.nbytes == 4)) {
178		if ((op->data.dir == SPI_MEM_DATA_IN) &&
179		    mtk_nor_match_read(op)) {
180			if ((op->addr.val & MTK_NOR_DMA_ALIGN_MASK) ||
181			    (op->data.nbytes < MTK_NOR_DMA_ALIGN))
182				op->data.nbytes = 1;
183			else if (!((ulong)(op->data.buf.in) &
184				   MTK_NOR_DMA_ALIGN_MASK))
185				op->data.nbytes &= ~MTK_NOR_DMA_ALIGN_MASK;
186			else if (op->data.nbytes > MTK_NOR_BOUNCE_BUF_SIZE)
187				op->data.nbytes = MTK_NOR_BOUNCE_BUF_SIZE;
188			return 0;
189		} else if (op->data.dir == SPI_MEM_DATA_OUT) {
190			if (op->data.nbytes >= MTK_NOR_PP_SIZE)
191				op->data.nbytes = MTK_NOR_PP_SIZE;
192			else
193				op->data.nbytes = 1;
194			return 0;
195		}
196	}
197
198	len = MTK_NOR_PRG_MAX_SIZE - op->cmd.nbytes - op->addr.nbytes -
199	      op->dummy.nbytes;
200	if (op->data.nbytes > len)
201		op->data.nbytes = len;
202
203	return 0;
204}
205
206static bool mtk_nor_supports_op(struct spi_mem *mem,
207				const struct spi_mem_op *op)
208{
209	size_t len;
210
211	if (op->cmd.buswidth != 1)
212		return false;
213
214	/* DTR ops not supported. */
215	if (op->cmd.dtr || op->addr.dtr || op->dummy.dtr || op->data.dtr)
216		return false;
217	if (op->cmd.nbytes != 1)
218		return false;
219
220	if ((op->addr.nbytes == 3) || (op->addr.nbytes == 4)) {
221		if ((op->data.dir == SPI_MEM_DATA_IN) && mtk_nor_match_read(op))
222			return true;
223		else if (op->data.dir == SPI_MEM_DATA_OUT)
224			return (op->addr.buswidth == 1) &&
225			       (op->dummy.buswidth == 0) &&
226			       (op->data.buswidth == 1);
227	}
228	len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;
229	if ((len > MTK_NOR_PRG_MAX_SIZE) ||
230	    ((op->data.nbytes) && (len == MTK_NOR_PRG_MAX_SIZE)))
231		return false;
232	return true;
233}
234
235static void mtk_nor_setup_bus(struct mtk_nor *sp, const struct spi_mem_op *op)
236{
237	u32 reg = 0;
238
239	if (op->addr.nbytes == 4)
240		reg |= MTK_NOR_4B_ADDR;
241
242	if (op->data.buswidth == 4) {
243		reg |= MTK_NOR_QUAD_READ;
244		writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA(4));
245		if (op->addr.buswidth == 4)
246			reg |= MTK_NOR_QUAD_ADDR;
247	} else if (op->data.buswidth == 2) {
248		reg |= MTK_NOR_DUAL_READ;
249		writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA(3));
250		if (op->addr.buswidth == 2)
251			reg |= MTK_NOR_DUAL_ADDR;
252	} else {
253		if (op->cmd.opcode == 0x0b)
254			mtk_nor_rmw(sp, MTK_NOR_REG_CFG1, MTK_NOR_FAST_READ, 0);
255		else
256			mtk_nor_rmw(sp, MTK_NOR_REG_CFG1, 0, MTK_NOR_FAST_READ);
257	}
258	mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, reg, MTK_NOR_BUS_MODE_MASK);
259}
260
261static int mtk_nor_read_dma(struct mtk_nor *sp, u32 from, unsigned int length,
262			    u8 *buffer)
263{
264	int ret = 0;
265	ulong delay;
266	u32 reg;
267	dma_addr_t dma_addr;
268
269	dma_addr = dma_map_single(sp->dev, buffer, length, DMA_FROM_DEVICE);
270	if (dma_mapping_error(sp->dev, dma_addr)) {
271		dev_err(sp->dev, "failed to map dma buffer.\n");
272		return -EINVAL;
273	}
274
275	writel(from, sp->base + MTK_NOR_REG_DMA_FADR);
276	writel(dma_addr, sp->base + MTK_NOR_REG_DMA_DADR);
277	writel(dma_addr + length, sp->base + MTK_NOR_REG_DMA_END_DADR);
278
279	if (sp->has_irq) {
280		reinit_completion(&sp->op_done);
281		mtk_nor_rmw(sp, MTK_NOR_REG_IRQ_EN, MTK_NOR_IRQ_DMA, 0);
282	}
283
284	mtk_nor_rmw(sp, MTK_NOR_REG_DMA_CTL, MTK_NOR_DMA_START, 0);
285
286	delay = CLK_TO_US(sp, (length + 5) * BITS_PER_BYTE);
287
288	if (sp->has_irq) {
289		if (!wait_for_completion_timeout(&sp->op_done,
290						 (delay + 1) * 100))
291			ret = -ETIMEDOUT;
292	} else {
293		ret = readl_poll_timeout(sp->base + MTK_NOR_REG_DMA_CTL, reg,
294					 !(reg & MTK_NOR_DMA_START), delay / 3,
295					 (delay + 1) * 100);
296	}
297
298	dma_unmap_single(sp->dev, dma_addr, length, DMA_FROM_DEVICE);
299	if (ret < 0)
300		dev_err(sp->dev, "dma read timeout.\n");
301
302	return ret;
303}
304
305static int mtk_nor_read_bounce(struct mtk_nor *sp, u32 from,
306			       unsigned int length, u8 *buffer)
307{
308	unsigned int rdlen;
309	int ret;
310
311	if (length & MTK_NOR_DMA_ALIGN_MASK)
312		rdlen = (length + MTK_NOR_DMA_ALIGN) & ~MTK_NOR_DMA_ALIGN_MASK;
313	else
314		rdlen = length;
315
316	ret = mtk_nor_read_dma(sp, from, rdlen, sp->buffer);
317	if (ret)
318		return ret;
319
320	memcpy(buffer, sp->buffer, length);
321	return 0;
322}
323
324static int mtk_nor_read_pio(struct mtk_nor *sp, const struct spi_mem_op *op)
325{
326	u8 *buf = op->data.buf.in;
327	int ret;
328
329	ret = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_READ, 6 * BITS_PER_BYTE);
330	if (!ret)
331		buf[0] = readb(sp->base + MTK_NOR_REG_RDATA);
332	return ret;
333}
334
335static int mtk_nor_write_buffer_enable(struct mtk_nor *sp)
336{
337	int ret;
338	u32 val;
339
340	if (sp->wbuf_en)
341		return 0;
342
343	val = readl(sp->base + MTK_NOR_REG_CFG2);
344	writel(val | MTK_NOR_WR_BUF_EN, sp->base + MTK_NOR_REG_CFG2);
345	ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CFG2, val,
346				 val & MTK_NOR_WR_BUF_EN, 0, 10000);
347	if (!ret)
348		sp->wbuf_en = true;
349	return ret;
350}
351
352static int mtk_nor_write_buffer_disable(struct mtk_nor *sp)
353{
354	int ret;
355	u32 val;
356
357	if (!sp->wbuf_en)
358		return 0;
359	val = readl(sp->base + MTK_NOR_REG_CFG2);
360	writel(val & ~MTK_NOR_WR_BUF_EN, sp->base + MTK_NOR_REG_CFG2);
361	ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CFG2, val,
362				 !(val & MTK_NOR_WR_BUF_EN), 0, 10000);
363	if (!ret)
364		sp->wbuf_en = false;
365	return ret;
366}
367
368static int mtk_nor_pp_buffered(struct mtk_nor *sp, const struct spi_mem_op *op)
369{
370	const u8 *buf = op->data.buf.out;
371	u32 val;
372	int ret, i;
373
374	ret = mtk_nor_write_buffer_enable(sp);
375	if (ret < 0)
376		return ret;
377
378	for (i = 0; i < op->data.nbytes; i += 4) {
379		val = buf[i + 3] << 24 | buf[i + 2] << 16 | buf[i + 1] << 8 |
380		      buf[i];
381		writel(val, sp->base + MTK_NOR_REG_PP_DATA);
382	}
383	return mtk_nor_cmd_exec(sp, MTK_NOR_CMD_WRITE,
384				(op->data.nbytes + 5) * BITS_PER_BYTE);
385}
386
387static int mtk_nor_pp_unbuffered(struct mtk_nor *sp,
388				 const struct spi_mem_op *op)
389{
390	const u8 *buf = op->data.buf.out;
391	int ret;
392
393	ret = mtk_nor_write_buffer_disable(sp);
394	if (ret < 0)
395		return ret;
396	writeb(buf[0], sp->base + MTK_NOR_REG_WDATA);
397	return mtk_nor_cmd_exec(sp, MTK_NOR_CMD_WRITE, 6 * BITS_PER_BYTE);
398}
399
400static int mtk_nor_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
401{
402	struct mtk_nor *sp = spi_controller_get_devdata(mem->spi->master);
403	int ret;
404
405	if ((op->data.nbytes == 0) ||
406	    ((op->addr.nbytes != 3) && (op->addr.nbytes != 4)))
407		return -ENOTSUPP;
408
409	if (op->data.dir == SPI_MEM_DATA_OUT) {
410		mtk_nor_set_addr(sp, op);
411		writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA0);
412		if (op->data.nbytes == MTK_NOR_PP_SIZE)
413			return mtk_nor_pp_buffered(sp, op);
414		return mtk_nor_pp_unbuffered(sp, op);
415	}
416
417	if ((op->data.dir == SPI_MEM_DATA_IN) && mtk_nor_match_read(op)) {
418		ret = mtk_nor_write_buffer_disable(sp);
419		if (ret < 0)
420			return ret;
421		mtk_nor_setup_bus(sp, op);
422		if (op->data.nbytes == 1) {
423			mtk_nor_set_addr(sp, op);
424			return mtk_nor_read_pio(sp, op);
425		} else if (((ulong)(op->data.buf.in) &
426			    MTK_NOR_DMA_ALIGN_MASK)) {
427			return mtk_nor_read_bounce(sp, op->addr.val,
428						   op->data.nbytes,
429						   op->data.buf.in);
430		} else {
431			return mtk_nor_read_dma(sp, op->addr.val,
432						op->data.nbytes,
433						op->data.buf.in);
434		}
435	}
436
437	return -ENOTSUPP;
438}
439
440static int mtk_nor_setup(struct spi_device *spi)
441{
442	struct mtk_nor *sp = spi_controller_get_devdata(spi->master);
443
444	if (spi->max_speed_hz && (spi->max_speed_hz < sp->spi_freq)) {
445		dev_err(&spi->dev, "spi clock should be %u Hz.\n",
446			sp->spi_freq);
447		return -EINVAL;
448	}
449	spi->max_speed_hz = sp->spi_freq;
450
451	return 0;
452}
453
454static int mtk_nor_transfer_one_message(struct spi_controller *master,
455					struct spi_message *m)
456{
457	struct mtk_nor *sp = spi_controller_get_devdata(master);
458	struct spi_transfer *t = NULL;
459	unsigned long trx_len = 0;
460	int stat = 0;
461	int reg_offset = MTK_NOR_REG_PRGDATA_MAX;
462	void __iomem *reg;
463	const u8 *txbuf;
464	u8 *rxbuf;
465	int i;
466
467	list_for_each_entry(t, &m->transfers, transfer_list) {
468		txbuf = t->tx_buf;
469		for (i = 0; i < t->len; i++, reg_offset--) {
470			reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
471			if (txbuf)
472				writeb(txbuf[i], reg);
473			else
474				writeb(0, reg);
475		}
476		trx_len += t->len;
477	}
478
479	writel(trx_len * BITS_PER_BYTE, sp->base + MTK_NOR_REG_PRG_CNT);
480
481	stat = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_PROGRAM,
482				trx_len * BITS_PER_BYTE);
483	if (stat < 0)
484		goto msg_done;
485
486	reg_offset = trx_len - 1;
487	list_for_each_entry(t, &m->transfers, transfer_list) {
488		rxbuf = t->rx_buf;
489		for (i = 0; i < t->len; i++, reg_offset--) {
490			reg = sp->base + MTK_NOR_REG_SHIFT(reg_offset);
491			if (rxbuf)
492				rxbuf[i] = readb(reg);
493		}
494	}
495
496	m->actual_length = trx_len;
497msg_done:
498	m->status = stat;
499	spi_finalize_current_message(master);
500
501	return 0;
502}
503
504static void mtk_nor_disable_clk(struct mtk_nor *sp)
505{
506	clk_disable_unprepare(sp->spi_clk);
507	clk_disable_unprepare(sp->ctlr_clk);
508}
509
510static int mtk_nor_enable_clk(struct mtk_nor *sp)
511{
512	int ret;
513
514	ret = clk_prepare_enable(sp->spi_clk);
515	if (ret)
516		return ret;
517
518	ret = clk_prepare_enable(sp->ctlr_clk);
519	if (ret) {
520		clk_disable_unprepare(sp->spi_clk);
521		return ret;
522	}
523
524	return 0;
525}
526
527static int mtk_nor_init(struct mtk_nor *sp)
528{
529	int ret;
530
531	ret = mtk_nor_enable_clk(sp);
532	if (ret)
533		return ret;
534
535	sp->spi_freq = clk_get_rate(sp->spi_clk);
536
537	writel(MTK_NOR_ENABLE_SF_CMD, sp->base + MTK_NOR_REG_WP);
538	mtk_nor_rmw(sp, MTK_NOR_REG_CFG2, MTK_NOR_WR_CUSTOM_OP_EN, 0);
539	mtk_nor_rmw(sp, MTK_NOR_REG_CFG3,
540		    MTK_NOR_DISABLE_WREN | MTK_NOR_DISABLE_SR_POLL, 0);
541
542	return ret;
543}
544
545static irqreturn_t mtk_nor_irq_handler(int irq, void *data)
546{
547	struct mtk_nor *sp = data;
548	u32 irq_status, irq_enabled;
549
550	irq_status = readl(sp->base + MTK_NOR_REG_IRQ_STAT);
551	irq_enabled = readl(sp->base + MTK_NOR_REG_IRQ_EN);
552	// write status back to clear interrupt
553	writel(irq_status, sp->base + MTK_NOR_REG_IRQ_STAT);
554
555	if (!(irq_status & irq_enabled))
556		return IRQ_NONE;
557
558	if (irq_status & MTK_NOR_IRQ_DMA) {
559		complete(&sp->op_done);
560		writel(0, sp->base + MTK_NOR_REG_IRQ_EN);
561	}
562
563	return IRQ_HANDLED;
564}
565
566static size_t mtk_max_msg_size(struct spi_device *spi)
567{
568	return MTK_NOR_PRG_MAX_SIZE;
569}
570
571static const struct spi_controller_mem_ops mtk_nor_mem_ops = {
572	.adjust_op_size = mtk_nor_adjust_op_size,
573	.supports_op = mtk_nor_supports_op,
574	.exec_op = mtk_nor_exec_op
575};
576
577static const struct of_device_id mtk_nor_match[] = {
578	{ .compatible = "mediatek,mt8173-nor" },
579	{ /* sentinel */ }
580};
581MODULE_DEVICE_TABLE(of, mtk_nor_match);
582
583static int mtk_nor_probe(struct platform_device *pdev)
584{
585	struct spi_controller *ctlr;
586	struct mtk_nor *sp;
587	void __iomem *base;
588	u8 *buffer;
589	struct clk *spi_clk, *ctlr_clk;
590	int ret, irq;
591
592	base = devm_platform_ioremap_resource(pdev, 0);
593	if (IS_ERR(base))
594		return PTR_ERR(base);
595
596	spi_clk = devm_clk_get(&pdev->dev, "spi");
597	if (IS_ERR(spi_clk))
598		return PTR_ERR(spi_clk);
599
600	ctlr_clk = devm_clk_get(&pdev->dev, "sf");
601	if (IS_ERR(ctlr_clk))
602		return PTR_ERR(ctlr_clk);
603
604	buffer = devm_kmalloc(&pdev->dev,
605			      MTK_NOR_BOUNCE_BUF_SIZE + MTK_NOR_DMA_ALIGN,
606			      GFP_KERNEL);
607	if (!buffer)
608		return -ENOMEM;
609
610	if ((ulong)buffer & MTK_NOR_DMA_ALIGN_MASK)
611		buffer = (u8 *)(((ulong)buffer + MTK_NOR_DMA_ALIGN) &
612				~MTK_NOR_DMA_ALIGN_MASK);
613
614	ctlr = spi_alloc_master(&pdev->dev, sizeof(*sp));
615	if (!ctlr) {
616		dev_err(&pdev->dev, "failed to allocate spi controller\n");
617		return -ENOMEM;
618	}
619
620	ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
621	ctlr->dev.of_node = pdev->dev.of_node;
622	ctlr->max_message_size = mtk_max_msg_size;
623	ctlr->mem_ops = &mtk_nor_mem_ops;
624	ctlr->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD;
625	ctlr->num_chipselect = 1;
626	ctlr->setup = mtk_nor_setup;
627	ctlr->transfer_one_message = mtk_nor_transfer_one_message;
628
629	dev_set_drvdata(&pdev->dev, ctlr);
630
631	sp = spi_controller_get_devdata(ctlr);
632	sp->base = base;
633	sp->buffer = buffer;
634	sp->has_irq = false;
635	sp->wbuf_en = false;
636	sp->ctlr = ctlr;
637	sp->dev = &pdev->dev;
638	sp->spi_clk = spi_clk;
639	sp->ctlr_clk = ctlr_clk;
640
641	irq = platform_get_irq_optional(pdev, 0);
642	if (irq < 0) {
643		dev_warn(sp->dev, "IRQ not available.");
644	} else {
645		writel(MTK_NOR_IRQ_MASK, base + MTK_NOR_REG_IRQ_STAT);
646		writel(0, base + MTK_NOR_REG_IRQ_EN);
647		ret = devm_request_irq(sp->dev, irq, mtk_nor_irq_handler, 0,
648				       pdev->name, sp);
649		if (ret < 0) {
650			dev_warn(sp->dev, "failed to request IRQ.");
651		} else {
652			init_completion(&sp->op_done);
653			sp->has_irq = true;
654		}
655	}
656
657	ret = mtk_nor_init(sp);
658	if (ret < 0) {
659		kfree(ctlr);
660		return ret;
661	}
662
663	dev_info(&pdev->dev, "spi frequency: %d Hz\n", sp->spi_freq);
664
665	return devm_spi_register_controller(&pdev->dev, ctlr);
666}
667
668static int mtk_nor_remove(struct platform_device *pdev)
669{
670	struct spi_controller *ctlr;
671	struct mtk_nor *sp;
672
673	ctlr = dev_get_drvdata(&pdev->dev);
674	sp = spi_controller_get_devdata(ctlr);
675
676	mtk_nor_disable_clk(sp);
677
678	return 0;
679}
680
681static struct platform_driver mtk_nor_driver = {
682	.driver = {
683		.name = DRIVER_NAME,
684		.of_match_table = mtk_nor_match,
685	},
686	.probe = mtk_nor_probe,
687	.remove = mtk_nor_remove,
688};
689
690module_platform_driver(mtk_nor_driver);
691
692MODULE_DESCRIPTION("Mediatek SPI NOR controller driver");
693MODULE_AUTHOR("Chuanhong Guo <gch981213@gmail.com>");
694MODULE_LICENSE("GPL v2");
695MODULE_ALIAS("platform:" DRIVER_NAME);