1/*
2 * Copyright (c) 2015 MediaTek Inc.
3 * Author: Leilk Liu <leilk.liu@mediatek.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 */
14
15#include <linux/clk.h>
16#include <linux/device.h>
17#include <linux/err.h>
18#include <linux/interrupt.h>
19#include <linux/io.h>
20#include <linux/ioport.h>
21#include <linux/module.h>
22#include <linux/of.h>
23#include <linux/of_gpio.h>
24#include <linux/platform_device.h>
25#include <linux/platform_data/spi-mt65xx.h>
26#include <linux/pm_runtime.h>
27#include <linux/spi/spi.h>
28
29#define SPI_CFG0_REG                      0x0000
30#define SPI_CFG1_REG                      0x0004
31#define SPI_TX_SRC_REG                    0x0008
32#define SPI_RX_DST_REG                    0x000c
33#define SPI_TX_DATA_REG                   0x0010
34#define SPI_RX_DATA_REG                   0x0014
35#define SPI_CMD_REG                       0x0018
36#define SPI_STATUS0_REG                   0x001c
37#define SPI_PAD_SEL_REG                   0x0024
38
39#define SPI_CFG0_SCK_HIGH_OFFSET          0
40#define SPI_CFG0_SCK_LOW_OFFSET           8
41#define SPI_CFG0_CS_HOLD_OFFSET           16
42#define SPI_CFG0_CS_SETUP_OFFSET          24
43
44#define SPI_CFG1_CS_IDLE_OFFSET           0
45#define SPI_CFG1_PACKET_LOOP_OFFSET       8
46#define SPI_CFG1_PACKET_LENGTH_OFFSET     16
47#define SPI_CFG1_GET_TICK_DLY_OFFSET      30
48
49#define SPI_CFG1_CS_IDLE_MASK             0xff
50#define SPI_CFG1_PACKET_LOOP_MASK         0xff00
51#define SPI_CFG1_PACKET_LENGTH_MASK       0x3ff0000
52
53#define SPI_CMD_ACT                  BIT(0)
54#define SPI_CMD_RESUME               BIT(1)
55#define SPI_CMD_RST                  BIT(2)
56#define SPI_CMD_PAUSE_EN             BIT(4)
57#define SPI_CMD_DEASSERT             BIT(5)
58#define SPI_CMD_CPHA                 BIT(8)
59#define SPI_CMD_CPOL                 BIT(9)
60#define SPI_CMD_RX_DMA               BIT(10)
61#define SPI_CMD_TX_DMA               BIT(11)
62#define SPI_CMD_TXMSBF               BIT(12)
63#define SPI_CMD_RXMSBF               BIT(13)
64#define SPI_CMD_RX_ENDIAN            BIT(14)
65#define SPI_CMD_TX_ENDIAN            BIT(15)
66#define SPI_CMD_FINISH_IE            BIT(16)
67#define SPI_CMD_PAUSE_IE             BIT(17)
68
69#define MT8173_SPI_MAX_PAD_SEL 3
70
71#define MTK_SPI_PAUSE_INT_STATUS 0x2
72
73#define MTK_SPI_IDLE 0
74#define MTK_SPI_PAUSED 1
75
76#define MTK_SPI_MAX_FIFO_SIZE 32
77#define MTK_SPI_PACKET_SIZE 1024
78
79struct mtk_spi_compatible {
80	bool need_pad_sel;
81	/* Must explicitly send dummy Tx bytes to do Rx only transfer */
82	bool must_tx;
83};
84
85struct mtk_spi {
86	void __iomem *base;
87	u32 state;
88	int pad_num;
89	u32 *pad_sel;
90	struct clk *parent_clk, *sel_clk, *spi_clk;
91	struct spi_transfer *cur_transfer;
92	u32 xfer_len;
93	struct scatterlist *tx_sgl, *rx_sgl;
94	u32 tx_sgl_len, rx_sgl_len;
95	const struct mtk_spi_compatible *dev_comp;
96};
97
98static const struct mtk_spi_compatible mt6589_compat;
99static const struct mtk_spi_compatible mt8135_compat;
100static const struct mtk_spi_compatible mt8173_compat = {
101	.need_pad_sel = true,
102	.must_tx = true,
103};
104
105/*
106 * A piece of default chip info unless the platform
107 * supplies it.
108 */
109static const struct mtk_chip_config mtk_default_chip_info = {
110	.rx_mlsb = 1,
111	.tx_mlsb = 1,
112};
113
114static const struct of_device_id mtk_spi_of_match[] = {
115	{ .compatible = "mediatek,mt6589-spi", .data = (void *)&mt6589_compat },
116	{ .compatible = "mediatek,mt8135-spi", .data = (void *)&mt8135_compat },
117	{ .compatible = "mediatek,mt8173-spi", .data = (void *)&mt8173_compat },
118	{}
119};
120MODULE_DEVICE_TABLE(of, mtk_spi_of_match);
121
122static void mtk_spi_reset(struct mtk_spi *mdata)
123{
124	u32 reg_val;
125
126	/* set the software reset bit in SPI_CMD_REG. */
127	reg_val = readl(mdata->base + SPI_CMD_REG);
128	reg_val |= SPI_CMD_RST;
129	writel(reg_val, mdata->base + SPI_CMD_REG);
130
131	reg_val = readl(mdata->base + SPI_CMD_REG);
132	reg_val &= ~SPI_CMD_RST;
133	writel(reg_val, mdata->base + SPI_CMD_REG);
134}
135
136static int mtk_spi_prepare_message(struct spi_master *master,
137				   struct spi_message *msg)
138{
139	u16 cpha, cpol;
140	u32 reg_val;
141	struct spi_device *spi = msg->spi;
142	struct mtk_chip_config *chip_config = spi->controller_data;
143	struct mtk_spi *mdata = spi_master_get_devdata(master);
144
145	cpha = spi->mode & SPI_CPHA ? 1 : 0;
146	cpol = spi->mode & SPI_CPOL ? 1 : 0;
147
148	reg_val = readl(mdata->base + SPI_CMD_REG);
149	if (cpha)
150		reg_val |= SPI_CMD_CPHA;
151	else
152		reg_val &= ~SPI_CMD_CPHA;
153	if (cpol)
154		reg_val |= SPI_CMD_CPOL;
155	else
156		reg_val &= ~SPI_CMD_CPOL;
157	writel(reg_val, mdata->base + SPI_CMD_REG);
158
159	reg_val = readl(mdata->base + SPI_CMD_REG);
160
161	/* set the mlsbx and mlsbtx */
162	if (chip_config->tx_mlsb)
163		reg_val |= SPI_CMD_TXMSBF;
164	else
165		reg_val &= ~SPI_CMD_TXMSBF;
166	if (chip_config->rx_mlsb)
167		reg_val |= SPI_CMD_RXMSBF;
168	else
169		reg_val &= ~SPI_CMD_RXMSBF;
170
171	/* set the tx/rx endian */
172#ifdef __LITTLE_ENDIAN
173	reg_val &= ~SPI_CMD_TX_ENDIAN;
174	reg_val &= ~SPI_CMD_RX_ENDIAN;
175#else
176	reg_val |= SPI_CMD_TX_ENDIAN;
177	reg_val |= SPI_CMD_RX_ENDIAN;
178#endif
179
180	/* set finish and pause interrupt always enable */
181	reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_IE;
182
183	/* disable dma mode */
184	reg_val &= ~(SPI_CMD_TX_DMA | SPI_CMD_RX_DMA);
185
186	/* disable deassert mode */
187	reg_val &= ~SPI_CMD_DEASSERT;
188
189	writel(reg_val, mdata->base + SPI_CMD_REG);
190
191	/* pad select */
192	if (mdata->dev_comp->need_pad_sel)
193		writel(mdata->pad_sel[spi->chip_select],
194		       mdata->base + SPI_PAD_SEL_REG);
195
196	return 0;
197}
198
199static void mtk_spi_set_cs(struct spi_device *spi, bool enable)
200{
201	u32 reg_val;
202	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
203
204	reg_val = readl(mdata->base + SPI_CMD_REG);
205	if (!enable) {
206		reg_val |= SPI_CMD_PAUSE_EN;
207		writel(reg_val, mdata->base + SPI_CMD_REG);
208	} else {
209		reg_val &= ~SPI_CMD_PAUSE_EN;
210		writel(reg_val, mdata->base + SPI_CMD_REG);
211		mdata->state = MTK_SPI_IDLE;
212		mtk_spi_reset(mdata);
213	}
214}
215
216static void mtk_spi_prepare_transfer(struct spi_master *master,
217				     struct spi_transfer *xfer)
218{
219	u32 spi_clk_hz, div, sck_time, cs_time, reg_val = 0;
220	struct mtk_spi *mdata = spi_master_get_devdata(master);
221
222	spi_clk_hz = clk_get_rate(mdata->spi_clk);
223	if (xfer->speed_hz < spi_clk_hz / 2)
224		div = DIV_ROUND_UP(spi_clk_hz, xfer->speed_hz);
225	else
226		div = 1;
227
228	sck_time = (div + 1) / 2;
229	cs_time = sck_time * 2;
230
231	reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_HIGH_OFFSET);
232	reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
233	reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
234	reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_SETUP_OFFSET);
235	writel(reg_val, mdata->base + SPI_CFG0_REG);
236
237	reg_val = readl(mdata->base + SPI_CFG1_REG);
238	reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
239	reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
240	writel(reg_val, mdata->base + SPI_CFG1_REG);
241}
242
243static void mtk_spi_setup_packet(struct spi_master *master)
244{
245	u32 packet_size, packet_loop, reg_val;
246	struct mtk_spi *mdata = spi_master_get_devdata(master);
247
248	packet_size = min_t(u32, mdata->xfer_len, MTK_SPI_PACKET_SIZE);
249	packet_loop = mdata->xfer_len / packet_size;
250
251	reg_val = readl(mdata->base + SPI_CFG1_REG);
252	reg_val &= ~(SPI_CFG1_PACKET_LENGTH_MASK | SPI_CFG1_PACKET_LOOP_MASK);
253	reg_val |= (packet_size - 1) << SPI_CFG1_PACKET_LENGTH_OFFSET;
254	reg_val |= (packet_loop - 1) << SPI_CFG1_PACKET_LOOP_OFFSET;
255	writel(reg_val, mdata->base + SPI_CFG1_REG);
256}
257
258static void mtk_spi_enable_transfer(struct spi_master *master)
259{
260	u32 cmd;
261	struct mtk_spi *mdata = spi_master_get_devdata(master);
262
263	cmd = readl(mdata->base + SPI_CMD_REG);
264	if (mdata->state == MTK_SPI_IDLE)
265		cmd |= SPI_CMD_ACT;
266	else
267		cmd |= SPI_CMD_RESUME;
268	writel(cmd, mdata->base + SPI_CMD_REG);
269}
270
271static int mtk_spi_get_mult_delta(u32 xfer_len)
272{
273	u32 mult_delta;
274
275	if (xfer_len > MTK_SPI_PACKET_SIZE)
276		mult_delta = xfer_len % MTK_SPI_PACKET_SIZE;
277	else
278		mult_delta = 0;
279
280	return mult_delta;
281}
282
283static void mtk_spi_update_mdata_len(struct spi_master *master)
284{
285	int mult_delta;
286	struct mtk_spi *mdata = spi_master_get_devdata(master);
287
288	if (mdata->tx_sgl_len && mdata->rx_sgl_len) {
289		if (mdata->tx_sgl_len > mdata->rx_sgl_len) {
290			mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
291			mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
292			mdata->rx_sgl_len = mult_delta;
293			mdata->tx_sgl_len -= mdata->xfer_len;
294		} else {
295			mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
296			mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
297			mdata->tx_sgl_len = mult_delta;
298			mdata->rx_sgl_len -= mdata->xfer_len;
299		}
300	} else if (mdata->tx_sgl_len) {
301		mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
302		mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
303		mdata->tx_sgl_len = mult_delta;
304	} else if (mdata->rx_sgl_len) {
305		mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
306		mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
307		mdata->rx_sgl_len = mult_delta;
308	}
309}
310
311static void mtk_spi_setup_dma_addr(struct spi_master *master,
312				   struct spi_transfer *xfer)
313{
314	struct mtk_spi *mdata = spi_master_get_devdata(master);
315
316	if (mdata->tx_sgl)
317		writel(xfer->tx_dma, mdata->base + SPI_TX_SRC_REG);
318	if (mdata->rx_sgl)
319		writel(xfer->rx_dma, mdata->base + SPI_RX_DST_REG);
320}
321
322static int mtk_spi_fifo_transfer(struct spi_master *master,
323				 struct spi_device *spi,
324				 struct spi_transfer *xfer)
325{
326	int cnt;
327	struct mtk_spi *mdata = spi_master_get_devdata(master);
328
329	mdata->cur_transfer = xfer;
330	mdata->xfer_len = xfer->len;
331	mtk_spi_prepare_transfer(master, xfer);
332	mtk_spi_setup_packet(master);
333
334	if (xfer->len % 4)
335		cnt = xfer->len / 4 + 1;
336	else
337		cnt = xfer->len / 4;
338	iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);
339
340	mtk_spi_enable_transfer(master);
341
342	return 1;
343}
344
345static int mtk_spi_dma_transfer(struct spi_master *master,
346				struct spi_device *spi,
347				struct spi_transfer *xfer)
348{
349	int cmd;
350	struct mtk_spi *mdata = spi_master_get_devdata(master);
351
352	mdata->tx_sgl = NULL;
353	mdata->rx_sgl = NULL;
354	mdata->tx_sgl_len = 0;
355	mdata->rx_sgl_len = 0;
356	mdata->cur_transfer = xfer;
357
358	mtk_spi_prepare_transfer(master, xfer);
359
360	cmd = readl(mdata->base + SPI_CMD_REG);
361	if (xfer->tx_buf)
362		cmd |= SPI_CMD_TX_DMA;
363	if (xfer->rx_buf)
364		cmd |= SPI_CMD_RX_DMA;
365	writel(cmd, mdata->base + SPI_CMD_REG);
366
367	if (xfer->tx_buf)
368		mdata->tx_sgl = xfer->tx_sg.sgl;
369	if (xfer->rx_buf)
370		mdata->rx_sgl = xfer->rx_sg.sgl;
371
372	if (mdata->tx_sgl) {
373		xfer->tx_dma = sg_dma_address(mdata->tx_sgl);
374		mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
375	}
376	if (mdata->rx_sgl) {
377		xfer->rx_dma = sg_dma_address(mdata->rx_sgl);
378		mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
379	}
380
381	mtk_spi_update_mdata_len(master);
382	mtk_spi_setup_packet(master);
383	mtk_spi_setup_dma_addr(master, xfer);
384	mtk_spi_enable_transfer(master);
385
386	return 1;
387}
388
389static int mtk_spi_transfer_one(struct spi_master *master,
390				struct spi_device *spi,
391				struct spi_transfer *xfer)
392{
393	if (master->can_dma(master, spi, xfer))
394		return mtk_spi_dma_transfer(master, spi, xfer);
395	else
396		return mtk_spi_fifo_transfer(master, spi, xfer);
397}
398
399static bool mtk_spi_can_dma(struct spi_master *master,
400			    struct spi_device *spi,
401			    struct spi_transfer *xfer)
402{
403	return xfer->len > MTK_SPI_MAX_FIFO_SIZE;
404}
405
406static int mtk_spi_setup(struct spi_device *spi)
407{
408	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
409
410	if (!spi->controller_data)
411		spi->controller_data = (void *)&mtk_default_chip_info;
412
413	if (mdata->dev_comp->need_pad_sel && gpio_is_valid(spi->cs_gpio))
414		gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
415
416	return 0;
417}
418
419static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
420{
421	u32 cmd, reg_val, cnt;
422	struct spi_master *master = dev_id;
423	struct mtk_spi *mdata = spi_master_get_devdata(master);
424	struct spi_transfer *trans = mdata->cur_transfer;
425
426	reg_val = readl(mdata->base + SPI_STATUS0_REG);
427	if (reg_val & MTK_SPI_PAUSE_INT_STATUS)
428		mdata->state = MTK_SPI_PAUSED;
429	else
430		mdata->state = MTK_SPI_IDLE;
431
432	if (!master->can_dma(master, master->cur_msg->spi, trans)) {
433		if (trans->rx_buf) {
434			if (mdata->xfer_len % 4)
435				cnt = mdata->xfer_len / 4 + 1;
436			else
437				cnt = mdata->xfer_len / 4;
438			ioread32_rep(mdata->base + SPI_RX_DATA_REG,
439				     trans->rx_buf, cnt);
440		}
441		spi_finalize_current_transfer(master);
442		return IRQ_HANDLED;
443	}
444
445	if (mdata->tx_sgl)
446		trans->tx_dma += mdata->xfer_len;
447	if (mdata->rx_sgl)
448		trans->rx_dma += mdata->xfer_len;
449
450	if (mdata->tx_sgl && (mdata->tx_sgl_len == 0)) {
451		mdata->tx_sgl = sg_next(mdata->tx_sgl);
452		if (mdata->tx_sgl) {
453			trans->tx_dma = sg_dma_address(mdata->tx_sgl);
454			mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
455		}
456	}
457	if (mdata->rx_sgl && (mdata->rx_sgl_len == 0)) {
458		mdata->rx_sgl = sg_next(mdata->rx_sgl);
459		if (mdata->rx_sgl) {
460			trans->rx_dma = sg_dma_address(mdata->rx_sgl);
461			mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
462		}
463	}
464
465	if (!mdata->tx_sgl && !mdata->rx_sgl) {
466		/* spi disable dma */
467		cmd = readl(mdata->base + SPI_CMD_REG);
468		cmd &= ~SPI_CMD_TX_DMA;
469		cmd &= ~SPI_CMD_RX_DMA;
470		writel(cmd, mdata->base + SPI_CMD_REG);
471
472		spi_finalize_current_transfer(master);
473		return IRQ_HANDLED;
474	}
475
476	mtk_spi_update_mdata_len(master);
477	mtk_spi_setup_packet(master);
478	mtk_spi_setup_dma_addr(master, trans);
479	mtk_spi_enable_transfer(master);
480
481	return IRQ_HANDLED;
482}
483
484static int mtk_spi_probe(struct platform_device *pdev)
485{
486	struct spi_master *master;
487	struct mtk_spi *mdata;
488	const struct of_device_id *of_id;
489	struct resource *res;
490	int i, irq, ret;
491
492	master = spi_alloc_master(&pdev->dev, sizeof(*mdata));
493	if (!master) {
494		dev_err(&pdev->dev, "failed to alloc spi master\n");
495		return -ENOMEM;
496	}
497
498	master->auto_runtime_pm = true;
499	master->dev.of_node = pdev->dev.of_node;
500	master->mode_bits = SPI_CPOL | SPI_CPHA;
501
502	master->set_cs = mtk_spi_set_cs;
503	master->prepare_message = mtk_spi_prepare_message;
504	master->transfer_one = mtk_spi_transfer_one;
505	master->can_dma = mtk_spi_can_dma;
506	master->setup = mtk_spi_setup;
507
508	of_id = of_match_node(mtk_spi_of_match, pdev->dev.of_node);
509	if (!of_id) {
510		dev_err(&pdev->dev, "failed to probe of_node\n");
511		ret = -EINVAL;
512		goto err_put_master;
513	}
514
515	mdata = spi_master_get_devdata(master);
516	mdata->dev_comp = of_id->data;
517	if (mdata->dev_comp->must_tx)
518		master->flags = SPI_MASTER_MUST_TX;
519
520	if (mdata->dev_comp->need_pad_sel) {
521		mdata->pad_num = of_property_count_u32_elems(
522			pdev->dev.of_node,
523			"mediatek,pad-select");
524		if (mdata->pad_num < 0) {
525			dev_err(&pdev->dev,
526				"No 'mediatek,pad-select' property\n");
527			ret = -EINVAL;
528			goto err_put_master;
529		}
530
531		mdata->pad_sel = devm_kmalloc_array(&pdev->dev, mdata->pad_num,
532						    sizeof(u32), GFP_KERNEL);
533		if (!mdata->pad_sel) {
534			ret = -ENOMEM;
535			goto err_put_master;
536		}
537
538		for (i = 0; i < mdata->pad_num; i++) {
539			of_property_read_u32_index(pdev->dev.of_node,
540						   "mediatek,pad-select",
541						   i, &mdata->pad_sel[i]);
542			if (mdata->pad_sel[i] > MT8173_SPI_MAX_PAD_SEL) {
543				dev_err(&pdev->dev, "wrong pad-sel[%d]: %u\n",
544					i, mdata->pad_sel[i]);
545				ret = -EINVAL;
546				goto err_put_master;
547			}
548		}
549	}
550
551	platform_set_drvdata(pdev, master);
552
553	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
554	if (!res) {
555		ret = -ENODEV;
556		dev_err(&pdev->dev, "failed to determine base address\n");
557		goto err_put_master;
558	}
559
560	mdata->base = devm_ioremap_resource(&pdev->dev, res);
561	if (IS_ERR(mdata->base)) {
562		ret = PTR_ERR(mdata->base);
563		goto err_put_master;
564	}
565
566	irq = platform_get_irq(pdev, 0);
567	if (irq < 0) {
568		dev_err(&pdev->dev, "failed to get irq (%d)\n", irq);
569		ret = irq;
570		goto err_put_master;
571	}
572
573	if (!pdev->dev.dma_mask)
574		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
575
576	ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt,
577			       IRQF_TRIGGER_NONE, dev_name(&pdev->dev), master);
578	if (ret) {
579		dev_err(&pdev->dev, "failed to register irq (%d)\n", ret);
580		goto err_put_master;
581	}
582
583	mdata->parent_clk = devm_clk_get(&pdev->dev, "parent-clk");
584	if (IS_ERR(mdata->parent_clk)) {
585		ret = PTR_ERR(mdata->parent_clk);
586		dev_err(&pdev->dev, "failed to get parent-clk: %d\n", ret);
587		goto err_put_master;
588	}
589
590	mdata->sel_clk = devm_clk_get(&pdev->dev, "sel-clk");
591	if (IS_ERR(mdata->sel_clk)) {
592		ret = PTR_ERR(mdata->sel_clk);
593		dev_err(&pdev->dev, "failed to get sel-clk: %d\n", ret);
594		goto err_put_master;
595	}
596
597	mdata->spi_clk = devm_clk_get(&pdev->dev, "spi-clk");
598	if (IS_ERR(mdata->spi_clk)) {
599		ret = PTR_ERR(mdata->spi_clk);
600		dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret);
601		goto err_put_master;
602	}
603
604	ret = clk_prepare_enable(mdata->spi_clk);
605	if (ret < 0) {
606		dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret);
607		goto err_put_master;
608	}
609
610	ret = clk_set_parent(mdata->sel_clk, mdata->parent_clk);
611	if (ret < 0) {
612		dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
613		goto err_disable_clk;
614	}
615
616	clk_disable_unprepare(mdata->spi_clk);
617
618	pm_runtime_enable(&pdev->dev);
619
620	ret = devm_spi_register_master(&pdev->dev, master);
621	if (ret) {
622		dev_err(&pdev->dev, "failed to register master (%d)\n", ret);
623		goto err_put_master;
624	}
625
626	if (mdata->dev_comp->need_pad_sel) {
627		if (mdata->pad_num != master->num_chipselect) {
628			dev_err(&pdev->dev,
629				"pad_num does not match num_chipselect(%d != %d)\n",
630				mdata->pad_num, master->num_chipselect);
631			ret = -EINVAL;
632			goto err_put_master;
633		}
634
635		if (!master->cs_gpios && master->num_chipselect > 1) {
636			dev_err(&pdev->dev,
637				"cs_gpios not specified and num_chipselect > 1\n");
638			ret = -EINVAL;
639			goto err_put_master;
640		}
641
642		if (master->cs_gpios) {
643			for (i = 0; i < master->num_chipselect; i++) {
644				ret = devm_gpio_request(&pdev->dev,
645							master->cs_gpios[i],
646							dev_name(&pdev->dev));
647				if (ret) {
648					dev_err(&pdev->dev,
649						"can't get CS GPIO %i\n", i);
650					goto err_put_master;
651				}
652			}
653		}
654	}
655
656	return 0;
657
658err_disable_clk:
659	clk_disable_unprepare(mdata->spi_clk);
660err_put_master:
661	spi_master_put(master);
662
663	return ret;
664}
665
666static int mtk_spi_remove(struct platform_device *pdev)
667{
668	struct spi_master *master = platform_get_drvdata(pdev);
669	struct mtk_spi *mdata = spi_master_get_devdata(master);
670
671	pm_runtime_disable(&pdev->dev);
672
673	mtk_spi_reset(mdata);
674	spi_master_put(master);
675
676	return 0;
677}
678
679#ifdef CONFIG_PM_SLEEP
680static int mtk_spi_suspend(struct device *dev)
681{
682	int ret;
683	struct spi_master *master = dev_get_drvdata(dev);
684	struct mtk_spi *mdata = spi_master_get_devdata(master);
685
686	ret = spi_master_suspend(master);
687	if (ret)
688		return ret;
689
690	if (!pm_runtime_suspended(dev))
691		clk_disable_unprepare(mdata->spi_clk);
692
693	return ret;
694}
695
696static int mtk_spi_resume(struct device *dev)
697{
698	int ret;
699	struct spi_master *master = dev_get_drvdata(dev);
700	struct mtk_spi *mdata = spi_master_get_devdata(master);
701
702	if (!pm_runtime_suspended(dev)) {
703		ret = clk_prepare_enable(mdata->spi_clk);
704		if (ret < 0) {
705			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
706			return ret;
707		}
708	}
709
710	ret = spi_master_resume(master);
711	if (ret < 0)
712		clk_disable_unprepare(mdata->spi_clk);
713
714	return ret;
715}
716#endif /* CONFIG_PM_SLEEP */
717
718#ifdef CONFIG_PM
719static int mtk_spi_runtime_suspend(struct device *dev)
720{
721	struct spi_master *master = dev_get_drvdata(dev);
722	struct mtk_spi *mdata = spi_master_get_devdata(master);
723
724	clk_disable_unprepare(mdata->spi_clk);
725
726	return 0;
727}
728
729static int mtk_spi_runtime_resume(struct device *dev)
730{
731	struct spi_master *master = dev_get_drvdata(dev);
732	struct mtk_spi *mdata = spi_master_get_devdata(master);
733	int ret;
734
735	ret = clk_prepare_enable(mdata->spi_clk);
736	if (ret < 0) {
737		dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
738		return ret;
739	}
740
741	return 0;
742}
743#endif /* CONFIG_PM */
744
745static const struct dev_pm_ops mtk_spi_pm = {
746	SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_suspend, mtk_spi_resume)
747	SET_RUNTIME_PM_OPS(mtk_spi_runtime_suspend,
748			   mtk_spi_runtime_resume, NULL)
749};
750
751static struct platform_driver mtk_spi_driver = {
752	.driver = {
753		.name = "mtk-spi",
754		.pm	= &mtk_spi_pm,
755		.of_match_table = mtk_spi_of_match,
756	},
757	.probe = mtk_spi_probe,
758	.remove = mtk_spi_remove,
759};
760
761module_platform_driver(mtk_spi_driver);
762
763MODULE_DESCRIPTION("MTK SPI Controller driver");
764MODULE_AUTHOR("Leilk Liu <leilk.liu@mediatek.com>");
765MODULE_LICENSE("GPL v2");
766MODULE_ALIAS("platform:mtk-spi");
767