[linux.git] / drivers / spi / spi-omap-100k.c

/*
 * OMAP7xx SPI 100k controller driver
 * Author: Fabrice Crohas <[email protected]>
 * from original omap1_mcspi driver
 *
 * Copyright (C) 2005, 2006 Nokia Corporation
 * Author:      Samuel Ortiz <[email protected]> and
 *              Juha Yrj�l� <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/gpio.h>
#include <linux/slab.h>

#include <linux/spi/spi.h>

#define OMAP1_SPI100K_MAX_FREQ          48000000

#define ICR_SPITAS      (OMAP7XX_ICR_BASE + 0x12)

#define SPI_SETUP1      0x00
#define SPI_SETUP2      0x02
#define SPI_CTRL        0x04
#define SPI_STATUS      0x06
#define SPI_TX_LSB      0x08
#define SPI_TX_MSB      0x0a
#define SPI_RX_LSB      0x0c
#define SPI_RX_MSB      0x0e

#define SPI_SETUP1_INT_READ_ENABLE      (1UL << 5)
#define SPI_SETUP1_INT_WRITE_ENABLE     (1UL << 4)
#define SPI_SETUP1_CLOCK_DIVISOR(x)     ((x) << 1)
#define SPI_SETUP1_CLOCK_ENABLE         (1UL << 0)

#define SPI_SETUP2_ACTIVE_EDGE_FALLING  (0UL << 0)
#define SPI_SETUP2_ACTIVE_EDGE_RISING   (1UL << 0)
#define SPI_SETUP2_NEGATIVE_LEVEL       (0UL << 5)
#define SPI_SETUP2_POSITIVE_LEVEL       (1UL << 5)
#define SPI_SETUP2_LEVEL_TRIGGER        (0UL << 10)
#define SPI_SETUP2_EDGE_TRIGGER         (1UL << 10)

#define SPI_CTRL_SEN(x)                 ((x) << 7)
#define SPI_CTRL_WORD_SIZE(x)           (((x) - 1) << 2)
#define SPI_CTRL_WR                     (1UL << 1)
#define SPI_CTRL_RD                     (1UL << 0)

#define SPI_STATUS_WE                   (1UL << 1)
#define SPI_STATUS_RD                   (1UL << 0)

/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
 * cache operations; better heuristics consider wordsize and bitrate.
 */
#define DMA_MIN_BYTES                   8

#define SPI_RUNNING	0
#define SPI_SHUTDOWN	1

struct omap1_spi100k {
	struct clk              *ick;
	struct clk              *fck;

	/* Virtual base address of the controller */
	void __iomem            *base;
};

struct omap1_spi100k_cs {
	void __iomem            *base;
	int                     word_len;
};

static void spi100k_enable_clock(struct spi_master *master)
{
	unsigned int val;
	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);

	/* enable SPI */
	val = readw(spi100k->base + SPI_SETUP1);
	val |= SPI_SETUP1_CLOCK_ENABLE;
	writew(val, spi100k->base + SPI_SETUP1);
}

static void spi100k_disable_clock(struct spi_master *master)
{
	unsigned int val;
	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);

	/* disable SPI */
	val = readw(spi100k->base + SPI_SETUP1);
	val &= ~SPI_SETUP1_CLOCK_ENABLE;
	writew(val, spi100k->base + SPI_SETUP1);
}

static void spi100k_write_data(struct spi_master *master, int len, int data)
{
	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);

	/* write 16-bit word, shifting 8-bit data if necessary */
	if (len <= 8) {
		data <<= 8;
		len = 16;
	}

	spi100k_enable_clock(master);
	writew(data , spi100k->base + SPI_TX_MSB);

	writew(SPI_CTRL_SEN(0) |
	       SPI_CTRL_WORD_SIZE(len) |
	       SPI_CTRL_WR,
	       spi100k->base + SPI_CTRL);

	/* Wait for bit ack send change */
	while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_WE) != SPI_STATUS_WE)
		;
	udelay(1000);

	spi100k_disable_clock(master);
}

static int spi100k_read_data(struct spi_master *master, int len)
{
	int dataH, dataL;
	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);

	/* Always do at least 16 bits */
	if (len <= 8)
		len = 16;

	spi100k_enable_clock(master);
	writew(SPI_CTRL_SEN(0) |
	       SPI_CTRL_WORD_SIZE(len) |
	       SPI_CTRL_RD,
	       spi100k->base + SPI_CTRL);

	while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_RD) != SPI_STATUS_RD)
		;
	udelay(1000);

	dataL = readw(spi100k->base + SPI_RX_LSB);
	dataH = readw(spi100k->base + SPI_RX_MSB);
	spi100k_disable_clock(master);

	return dataL;
}

static void spi100k_open(struct spi_master *master)
{
	/* get control of SPI */
	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);

	writew(SPI_SETUP1_INT_READ_ENABLE |
	       SPI_SETUP1_INT_WRITE_ENABLE |
	       SPI_SETUP1_CLOCK_DIVISOR(0), spi100k->base + SPI_SETUP1);

	/* configure clock and interrupts */
	writew(SPI_SETUP2_ACTIVE_EDGE_FALLING |
	       SPI_SETUP2_NEGATIVE_LEVEL |
	       SPI_SETUP2_LEVEL_TRIGGER, spi100k->base + SPI_SETUP2);
}

static void omap1_spi100k_force_cs(struct omap1_spi100k *spi100k, int enable)
{
	if (enable)
		writew(0x05fc, spi100k->base + SPI_CTRL);
	else
		writew(0x05fd, spi100k->base + SPI_CTRL);
}

static unsigned
omap1_spi100k_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
{
	struct omap1_spi100k_cs *cs = spi->controller_state;
	unsigned int            count, c;
	int                     word_len;

	count = xfer->len;
	c = count;
	word_len = cs->word_len;

	if (word_len <= 8) {
		u8              *rx;
		const u8        *tx;

		rx = xfer->rx_buf;
		tx = xfer->tx_buf;
		do {
			c -= 1;
			if (xfer->tx_buf != NULL)
				spi100k_write_data(spi->master, word_len, *tx++);
			if (xfer->rx_buf != NULL)
				*rx++ = spi100k_read_data(spi->master, word_len);
		} while (c);
	} else if (word_len <= 16) {
		u16             *rx;
		const u16       *tx;

		rx = xfer->rx_buf;
		tx = xfer->tx_buf;
		do {
			c -= 2;
			if (xfer->tx_buf != NULL)
				spi100k_write_data(spi->master, word_len, *tx++);
			if (xfer->rx_buf != NULL)
				*rx++ = spi100k_read_data(spi->master, word_len);
		} while (c);
	} else if (word_len <= 32) {
		u32             *rx;
		const u32       *tx;

		rx = xfer->rx_buf;
		tx = xfer->tx_buf;
		do {
			c -= 4;
			if (xfer->tx_buf != NULL)
				spi100k_write_data(spi->master, word_len, *tx);
			if (xfer->rx_buf != NULL)
				*rx = spi100k_read_data(spi->master, word_len);
		} while (c);
	}
	return count - c;
}

/* called only when no transfer is active to this device */
static int omap1_spi100k_setup_transfer(struct spi_device *spi,
		struct spi_transfer *t)
{
	struct omap1_spi100k *spi100k = spi_master_get_devdata(spi->master);
	struct omap1_spi100k_cs *cs = spi->controller_state;
	u8 word_len;

	if (t != NULL)
		word_len = t->bits_per_word;
	else
		word_len = spi->bits_per_word;

	if (spi->bits_per_word > 32)
		return -EINVAL;
	cs->word_len = word_len;

	/* SPI init before transfer */
	writew(0x3e , spi100k->base + SPI_SETUP1);
	writew(0x00 , spi100k->base + SPI_STATUS);
	writew(0x3e , spi100k->base + SPI_CTRL);

	return 0;
}

/* the spi->mode bits understood by this driver: */
#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)

static int omap1_spi100k_setup(struct spi_device *spi)
{
	int                     ret;
	struct omap1_spi100k    *spi100k;
	struct omap1_spi100k_cs *cs = spi->controller_state;

	spi100k = spi_master_get_devdata(spi->master);

	if (!cs) {
		cs = devm_kzalloc(&spi->dev, sizeof(*cs), GFP_KERNEL);
		if (!cs)
			return -ENOMEM;
		cs->base = spi100k->base + spi->chip_select * 0x14;
		spi->controller_state = cs;
	}

	spi100k_open(spi->master);

	clk_prepare_enable(spi100k->ick);
	clk_prepare_enable(spi100k->fck);

	ret = omap1_spi100k_setup_transfer(spi, NULL);

	clk_disable_unprepare(spi100k->ick);
	clk_disable_unprepare(spi100k->fck);

	return ret;
}

static int omap1_spi100k_transfer_one_message(struct spi_master *master,
					      struct spi_message *m)
{
	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	struct spi_device *spi = m->spi;
	struct spi_transfer *t = NULL;
	int cs_active = 0;
	int status = 0;

	list_for_each_entry(t, &m->transfers, transfer_list) {
		if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
			status = -EINVAL;
			break;
		}
		status = omap1_spi100k_setup_transfer(spi, t);
		if (status < 0)
			break;

		if (!cs_active) {
			omap1_spi100k_force_cs(spi100k, 1);
			cs_active = 1;
		}

		if (t->len) {
			unsigned count;

			count = omap1_spi100k_txrx_pio(spi, t);
			m->actual_length += count;

			if (count != t->len) {
				status = -EIO;
				break;
			}
		}

		if (t->delay_usecs)
			udelay(t->delay_usecs);

		/* ignore the "leave it on after last xfer" hint */

		if (t->cs_change) {
			omap1_spi100k_force_cs(spi100k, 0);
			cs_active = 0;
		}
	}

	status = omap1_spi100k_setup_transfer(spi, NULL);

	if (cs_active)
		omap1_spi100k_force_cs(spi100k, 0);

	m->status = status;

	spi_finalize_current_message(master);

	return status;
}

static int omap1_spi100k_probe(struct platform_device *pdev)
{
	struct spi_master       *master;
	struct omap1_spi100k    *spi100k;
	int                     status = 0;

	if (!pdev->id)
		return -EINVAL;

	master = spi_alloc_master(&pdev->dev, sizeof(*spi100k));
	if (master == NULL) {
		dev_dbg(&pdev->dev, "master allocation failed\n");
		return -ENOMEM;
	}

	if (pdev->id != -1)
		master->bus_num = pdev->id;

	master->setup = omap1_spi100k_setup;
	master->transfer_one_message = omap1_spi100k_transfer_one_message;
	master->num_chipselect = 2;
	master->mode_bits = MODEBITS;
	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
	master->min_speed_hz = OMAP1_SPI100K_MAX_FREQ/(1<<16);
	master->max_speed_hz = OMAP1_SPI100K_MAX_FREQ;
	master->auto_runtime_pm = true;

	spi100k = spi_master_get_devdata(master);

	/*
	 * The memory region base address is taken as the platform_data.
	 * You should allocate this with ioremap() before initializing
	 * the SPI.
	 */
	spi100k->base = (void __iomem *)dev_get_platdata(&pdev->dev);

	spi100k->ick = devm_clk_get(&pdev->dev, "ick");
	if (IS_ERR(spi100k->ick)) {
		dev_dbg(&pdev->dev, "can't get spi100k_ick\n");
		status = PTR_ERR(spi100k->ick);
		goto err;
	}

	spi100k->fck = devm_clk_get(&pdev->dev, "fck");
	if (IS_ERR(spi100k->fck)) {
		dev_dbg(&pdev->dev, "can't get spi100k_fck\n");
		status = PTR_ERR(spi100k->fck);
		goto err;
	}

	status = clk_prepare_enable(spi100k->ick);
	if (status != 0) {
		dev_err(&pdev->dev, "failed to enable ick: %d\n", status);
		goto err;
	}

	status = clk_prepare_enable(spi100k->fck);
	if (status != 0) {
		dev_err(&pdev->dev, "failed to enable fck: %d\n", status);
		goto err_ick;
	}

	pm_runtime_enable(&pdev->dev);
	pm_runtime_set_active(&pdev->dev);

	status = devm_spi_register_master(&pdev->dev, master);
	if (status < 0)
		goto err_fck;

	return status;

err_fck:
	clk_disable_unprepare(spi100k->fck);
err_ick:
	clk_disable_unprepare(spi100k->ick);
err:
	spi_master_put(master);
	return status;
}

static int omap1_spi100k_remove(struct platform_device *pdev)
{
	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);

	pm_runtime_disable(&pdev->dev);

	clk_disable_unprepare(spi100k->fck);
	clk_disable_unprepare(spi100k->ick);

	return 0;
}

#ifdef CONFIG_PM
static int omap1_spi100k_runtime_suspend(struct device *dev)
{
	struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);

	clk_disable_unprepare(spi100k->ick);
	clk_disable_unprepare(spi100k->fck);

	return 0;
}

static int omap1_spi100k_runtime_resume(struct device *dev)
{
	struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	int ret;

	ret = clk_prepare_enable(spi100k->ick);
	if (ret != 0) {
		dev_err(dev, "Failed to enable ick: %d\n", ret);
		return ret;
	}

	ret = clk_prepare_enable(spi100k->fck);
	if (ret != 0) {
		dev_err(dev, "Failed to enable fck: %d\n", ret);
		clk_disable_unprepare(spi100k->ick);
		return ret;
	}

	return 0;
}
#endif

static const struct dev_pm_ops omap1_spi100k_pm = {
	SET_RUNTIME_PM_OPS(omap1_spi100k_runtime_suspend,
			   omap1_spi100k_runtime_resume, NULL)
};

static struct platform_driver omap1_spi100k_driver = {
	.driver = {
		.name		= "omap1_spi100k",
		.pm		= &omap1_spi100k_pm,
	},
	.probe		= omap1_spi100k_probe,
	.remove		= omap1_spi100k_remove,
};

module_platform_driver(omap1_spi100k_driver);

MODULE_DESCRIPTION("OMAP7xx SPI 100k controller driver");
MODULE_AUTHOR("Fabrice Crohas <[email protected]>");
MODULE_LICENSE("GPL");
Commit	Line	Data
35c9049b CM	1	/*
	2	* OMAP7xx SPI 100k controller driver
	3	* Author: Fabrice Crohas <[email protected]>
	4	* from original omap1_mcspi driver
	5	*
	6	* Copyright (C) 2005, 2006 Nokia Corporation
	7	* Author: Samuel Ortiz <[email protected]> and
	8	* Juha Yrj�l� <[email protected]>
	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License as published by
	12	* the Free Software Foundation; either version 2 of the License, or
	13	* (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	* GNU General Public License for more details.
35c9049b CM	19	*/
	20	#include <linux/kernel.h>
	21	#include <linux/init.h>
	22	#include <linux/interrupt.h>
	23	#include <linux/module.h>
	24	#include <linux/device.h>
	25	#include <linux/delay.h>
	26	#include <linux/platform_device.h>
db91841b	27	#include <linux/pm_runtime.h>
35c9049b CM	28	#include <linux/err.h>
	29	#include <linux/clk.h>
	30	#include <linux/io.h>
	31	#include <linux/gpio.h>
5a0e3ad6	32	#include <linux/slab.h>
35c9049b CM	33
	34	#include <linux/spi/spi.h>
	35
35c9049b CM	36	#define OMAP1_SPI100K_MAX_FREQ 48000000
	37
	38	#define ICR_SPITAS (OMAP7XX_ICR_BASE + 0x12)
	39
	40	#define SPI_SETUP1 0x00
	41	#define SPI_SETUP2 0x02
	42	#define SPI_CTRL 0x04
	43	#define SPI_STATUS 0x06
	44	#define SPI_TX_LSB 0x08
	45	#define SPI_TX_MSB 0x0a
	46	#define SPI_RX_LSB 0x0c
	47	#define SPI_RX_MSB 0x0e
	48
	49	#define SPI_SETUP1_INT_READ_ENABLE (1UL << 5)
	50	#define SPI_SETUP1_INT_WRITE_ENABLE (1UL << 4)
	51	#define SPI_SETUP1_CLOCK_DIVISOR(x) ((x) << 1)
	52	#define SPI_SETUP1_CLOCK_ENABLE (1UL << 0)
	53
	54	#define SPI_SETUP2_ACTIVE_EDGE_FALLING (0UL << 0)
	55	#define SPI_SETUP2_ACTIVE_EDGE_RISING (1UL << 0)
	56	#define SPI_SETUP2_NEGATIVE_LEVEL (0UL << 5)
	57	#define SPI_SETUP2_POSITIVE_LEVEL (1UL << 5)
	58	#define SPI_SETUP2_LEVEL_TRIGGER (0UL << 10)
	59	#define SPI_SETUP2_EDGE_TRIGGER (1UL << 10)
	60
	61	#define SPI_CTRL_SEN(x) ((x) << 7)
	62	#define SPI_CTRL_WORD_SIZE(x) (((x) - 1) << 2)
	63	#define SPI_CTRL_WR (1UL << 1)
	64	#define SPI_CTRL_RD (1UL << 0)
	65
	66	#define SPI_STATUS_WE (1UL << 1)
	67	#define SPI_STATUS_RD (1UL << 0)
	68
35c9049b CM	69	/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
	70	* cache operations; better heuristics consider wordsize and bitrate.
	71	*/
	72	#define DMA_MIN_BYTES 8
	73
	74	#define SPI_RUNNING 0
	75	#define SPI_SHUTDOWN 1
	76
	77	struct omap1_spi100k {
35c9049b CM	78	struct clk *ick;
	79	struct clk *fck;
	80
	81	/* Virtual base address of the controller */
	82	void __iomem *base;
35c9049b CM	83	};
	84
	85	struct omap1_spi100k_cs {
	86	void __iomem *base;
	87	int word_len;
	88	};
	89
35c9049b CM	90	static void spi100k_enable_clock(struct spi_master *master)
	91	{
	92	unsigned int val;
	93	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	94
	95	/* enable SPI */
	96	val = readw(spi100k->base + SPI_SETUP1);
	97	val \|= SPI_SETUP1_CLOCK_ENABLE;
	98	writew(val, spi100k->base + SPI_SETUP1);
	99	}
	100
	101	static void spi100k_disable_clock(struct spi_master *master)
	102	{
	103	unsigned int val;
	104	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	105
	106	/* disable SPI */
	107	val = readw(spi100k->base + SPI_SETUP1);
	108	val &= ~SPI_SETUP1_CLOCK_ENABLE;
	109	writew(val, spi100k->base + SPI_SETUP1);
	110	}
	111
	112	static void spi100k_write_data(struct spi_master *master, int len, int data)
	113	{
	114	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	115
5c2818cd CM	116	/* write 16-bit word, shifting 8-bit data if necessary */
	117	if (len <= 8) {
	118	data <<= 8;
	119	len = 16;
	120	}
	121
35c9049b	122	spi100k_enable_clock(master);
31804f63	123	writew(data , spi100k->base + SPI_TX_MSB);
35c9049b CM	124
	125	writew(SPI_CTRL_SEN(0) \|
	126	SPI_CTRL_WORD_SIZE(len) \|
	127	SPI_CTRL_WR,
	128	spi100k->base + SPI_CTRL);
	129
	130	/* Wait for bit ack send change */
31804f63 JH	131	while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_WE) != SPI_STATUS_WE)
31804f63 JH	132	;
35c9049b CM	133	udelay(1000);
	134
	135	spi100k_disable_clock(master);
	136	}
	137
	138	static int spi100k_read_data(struct spi_master *master, int len)
	139	{
31804f63	140	int dataH, dataL;
35c9049b CM	141	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
35c9049b CM	142
5c2818cd CM	143	/* Always do at least 16 bits */
	144	if (len <= 8)
	145	len = 16;
	146
35c9049b CM	147	spi100k_enable_clock(master);
	148	writew(SPI_CTRL_SEN(0) \|
	149	SPI_CTRL_WORD_SIZE(len) \|
	150	SPI_CTRL_RD,
	151	spi100k->base + SPI_CTRL);
	152
31804f63 JH	153	while ((readw(spi100k->base + SPI_STATUS) & SPI_STATUS_RD) != SPI_STATUS_RD)
31804f63 JH	154	;
35c9049b CM	155	udelay(1000);
	156
	157	dataL = readw(spi100k->base + SPI_RX_LSB);
	158	dataH = readw(spi100k->base + SPI_RX_MSB);
	159	spi100k_disable_clock(master);
	160
	161	return dataL;
	162	}
	163
	164	static void spi100k_open(struct spi_master *master)
	165	{
	166	/* get control of SPI */
	167	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	168
	169	writew(SPI_SETUP1_INT_READ_ENABLE \|
	170	SPI_SETUP1_INT_WRITE_ENABLE \|
	171	SPI_SETUP1_CLOCK_DIVISOR(0), spi100k->base + SPI_SETUP1);
	172
	173	/* configure clock and interrupts */
	174	writew(SPI_SETUP2_ACTIVE_EDGE_FALLING \|
	175	SPI_SETUP2_NEGATIVE_LEVEL \|
	176	SPI_SETUP2_LEVEL_TRIGGER, spi100k->base + SPI_SETUP2);
	177	}
	178
	179	static void omap1_spi100k_force_cs(struct omap1_spi100k *spi100k, int enable)
	180	{
	181	if (enable)
	182	writew(0x05fc, spi100k->base + SPI_CTRL);
	183	else
	184	writew(0x05fd, spi100k->base + SPI_CTRL);
	185	}
	186
	187	static unsigned
	188	omap1_spi100k_txrx_pio(struct spi_device spi, struct spi_transfer xfer)
	189	{
35c9049b CM	190	struct omap1_spi100k_cs *cs = spi->controller_state;
	191	unsigned int count, c;
	192	int word_len;
	193
35c9049b CM	194	count = xfer->len;
	195	c = count;
	196	word_len = cs->word_len;
	197
35c9049b CM	198	if (word_len <= 8) {
	199	u8 *rx;
	200	const u8 *tx;
	201
	202	rx = xfer->rx_buf;
	203	tx = xfer->tx_buf;
	204	do {
31804f63	205	c -= 1;
35c9049b	206	if (xfer->tx_buf != NULL)
5c2818cd	207	spi100k_write_data(spi->master, word_len, *tx++);
35c9049b	208	if (xfer->rx_buf != NULL)
5c2818cd	209	*rx++ = spi100k_read_data(spi->master, word_len);
31804f63	210	} while (c);
35c9049b CM	211	} else if (word_len <= 16) {
	212	u16 *rx;
	213	const u16 *tx;
	214
	215	rx = xfer->rx_buf;
	216	tx = xfer->tx_buf;
	217	do {
31804f63	218	c -= 2;
35c9049b	219	if (xfer->tx_buf != NULL)
31804f63	220	spi100k_write_data(spi->master, word_len, *tx++);
35c9049b	221	if (xfer->rx_buf != NULL)
31804f63 JH	222	*rx++ = spi100k_read_data(spi->master, word_len);
31804f63 JH	223	} while (c);
35c9049b CM	224	} else if (word_len <= 32) {
	225	u32 *rx;
	226	const u32 *tx;
	227
	228	rx = xfer->rx_buf;
	229	tx = xfer->tx_buf;
	230	do {
31804f63	231	c -= 4;
35c9049b	232	if (xfer->tx_buf != NULL)
31804f63	233	spi100k_write_data(spi->master, word_len, *tx);
35c9049b	234	if (xfer->rx_buf != NULL)
31804f63 JH	235	*rx = spi100k_read_data(spi->master, word_len);
31804f63 JH	236	} while (c);
35c9049b CM	237	}
	238	return count - c;
	239	}
	240
	241	/* called only when no transfer is active to this device */
	242	static int omap1_spi100k_setup_transfer(struct spi_device *spi,
	243	struct spi_transfer *t)
	244	{
	245	struct omap1_spi100k *spi100k = spi_master_get_devdata(spi->master);
	246	struct omap1_spi100k_cs *cs = spi->controller_state;
76f67ea9	247	u8 word_len;
35c9049b	248
76f67ea9	249	if (t != NULL)
35c9049b	250	word_len = t->bits_per_word;
76f67ea9 JN	251	else
76f67ea9 JN	252	word_len = spi->bits_per_word;
35c9049b CM	253
	254	if (spi->bits_per_word > 32)
	255	return -EINVAL;
	256	cs->word_len = word_len;
	257
	258	/* SPI init before transfer */
	259	writew(0x3e , spi100k->base + SPI_SETUP1);
	260	writew(0x00 , spi100k->base + SPI_STATUS);
	261	writew(0x3e , spi100k->base + SPI_CTRL);
	262
	263	return 0;
	264	}
	265
	266	/* the spi->mode bits understood by this driver: */
	267	#define MODEBITS (SPI_CPOL \| SPI_CPHA \| SPI_CS_HIGH)
	268
	269	static int omap1_spi100k_setup(struct spi_device *spi)
	270	{
	271	int ret;
	272	struct omap1_spi100k *spi100k;
	273	struct omap1_spi100k_cs *cs = spi->controller_state;
	274
35c9049b CM	275	spi100k = spi_master_get_devdata(spi->master);
	276
	277	if (!cs) {
d1c18caa	278	cs = devm_kzalloc(&spi->dev, sizeof(*cs), GFP_KERNEL);
35c9049b CM	279	if (!cs)
	280	return -ENOMEM;
	281	cs->base = spi100k->base + spi->chip_select * 0x14;
	282	spi->controller_state = cs;
	283	}
	284
	285	spi100k_open(spi->master);
	286
13cd19e8 MB	287	clk_prepare_enable(spi100k->ick);
13cd19e8 MB	288	clk_prepare_enable(spi100k->fck);
35c9049b CM	289
	290	ret = omap1_spi100k_setup_transfer(spi, NULL);
	291
13cd19e8 MB	292	clk_disable_unprepare(spi100k->ick);
13cd19e8 MB	293	clk_disable_unprepare(spi100k->fck);
35c9049b CM	294
	295	return ret;
	296	}
	297
e8153ab3 MB	298	static int omap1_spi100k_transfer_one_message(struct spi_master *master,
	299	struct spi_message *m)
	300	{
	301	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	302	struct spi_device *spi = m->spi;
	303	struct spi_transfer *t = NULL;
	304	int cs_active = 0;
e8153ab3 MB	305	int status = 0;
	306
	307	list_for_each_entry(t, &m->transfers, transfer_list) {
	308	if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {
	309	status = -EINVAL;
	310	break;
	311	}
76f67ea9 JN	312	status = omap1_spi100k_setup_transfer(spi, t);
	313	if (status < 0)
	314	break;
e8153ab3 MB	315
	316	if (!cs_active) {
	317	omap1_spi100k_force_cs(spi100k, 1);
	318	cs_active = 1;
	319	}
	320
	321	if (t->len) {
	322	unsigned count;
	323
	324	count = omap1_spi100k_txrx_pio(spi, t);
	325	m->actual_length += count;
	326
	327	if (count != t->len) {
	328	status = -EIO;
	329	break;
	330	}
	331	}
	332
	333	if (t->delay_usecs)
	334	udelay(t->delay_usecs);
	335
	336	/* ignore the "leave it on after last xfer" hint */
	337
	338	if (t->cs_change) {
	339	omap1_spi100k_force_cs(spi100k, 0);
	340	cs_active = 0;
	341	}
	342	}
	343
76f67ea9	344	status = omap1_spi100k_setup_transfer(spi, NULL);
e8153ab3 MB	345
	346	if (cs_active)
	347	omap1_spi100k_force_cs(spi100k, 0);
	348
	349	m->status = status;
da60b855 MB	350
da60b855 MB	351	spi_finalize_current_message(master);
e8153ab3 MB	352
	353	return status;
	354	}
	355
fd4a319b	356	static int omap1_spi100k_probe(struct platform_device *pdev)
35c9049b CM	357	{
	358	struct spi_master *master;
	359	struct omap1_spi100k *spi100k;
	360	int status = 0;
	361
	362	if (!pdev->id)
	363	return -EINVAL;
	364
31804f63	365	master = spi_alloc_master(&pdev->dev, sizeof(*spi100k));
35c9049b CM	366	if (master == NULL) {
	367	dev_dbg(&pdev->dev, "master allocation failed\n");
	368	return -ENOMEM;
	369	}
	370
	371	if (pdev->id != -1)
31804f63	372	master->bus_num = pdev->id;
35c9049b CM	373
35c9049b CM	374	master->setup = omap1_spi100k_setup;
da60b855	375	master->transfer_one_message = omap1_spi100k_transfer_one_message;
35c9049b CM	376	master->num_chipselect = 2;
35c9049b CM	377	master->mode_bits = MODEBITS;
24778be2	378	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
69ea672a MB	379	master->min_speed_hz = OMAP1_SPI100K_MAX_FREQ/(1<<16);
69ea672a MB	380	master->max_speed_hz = OMAP1_SPI100K_MAX_FREQ;
db91841b	381	master->auto_runtime_pm = true;
35c9049b	382
35c9049b	383	spi100k = spi_master_get_devdata(master);
35c9049b CM	384
	385	/*
	386	* The memory region base address is taken as the platform_data.
	387	* You should allocate this with ioremap() before initializing
	388	* the SPI.
	389	*/
8074cf06	390	spi100k->base = (void __iomem *)dev_get_platdata(&pdev->dev);
35c9049b	391
022a9412	392	spi100k->ick = devm_clk_get(&pdev->dev, "ick");
35c9049b CM	393	if (IS_ERR(spi100k->ick)) {
	394	dev_dbg(&pdev->dev, "can't get spi100k_ick\n");
	395	status = PTR_ERR(spi100k->ick);
022a9412	396	goto err;
35c9049b CM	397	}
35c9049b CM	398
022a9412	399	spi100k->fck = devm_clk_get(&pdev->dev, "fck");
35c9049b CM	400	if (IS_ERR(spi100k->fck)) {
	401	dev_dbg(&pdev->dev, "can't get spi100k_fck\n");
	402	status = PTR_ERR(spi100k->fck);
022a9412	403	goto err;
35c9049b CM	404	}
35c9049b CM	405
db91841b MB	406	status = clk_prepare_enable(spi100k->ick);
	407	if (status != 0) {
	408	dev_err(&pdev->dev, "failed to enable ick: %d\n", status);
	409	goto err;
	410	}
	411
	412	status = clk_prepare_enable(spi100k->fck);
	413	if (status != 0) {
	414	dev_err(&pdev->dev, "failed to enable fck: %d\n", status);
	415	goto err_ick;
	416	}
	417
	418	pm_runtime_enable(&pdev->dev);
	419	pm_runtime_set_active(&pdev->dev);
	420
5c4c5c7b	421	status = devm_spi_register_master(&pdev->dev, master);
35c9049b	422	if (status < 0)
db91841b	423	goto err_fck;
35c9049b	424
35c9049b CM	425	return status;
35c9049b CM	426
db91841b MB	427	err_fck:
	428	clk_disable_unprepare(spi100k->fck);
	429	err_ick:
	430	clk_disable_unprepare(spi100k->ick);
022a9412	431	err:
35c9049b CM	432	spi_master_put(master);
	433	return status;
	434	}
	435
db91841b MB	436	static int omap1_spi100k_remove(struct platform_device *pdev)
	437	{
	438	struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
	439	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	440
	441	pm_runtime_disable(&pdev->dev);
	442
	443	clk_disable_unprepare(spi100k->fck);
	444	clk_disable_unprepare(spi100k->ick);
	445
	446	return 0;
	447	}
	448
	449	#ifdef CONFIG_PM
	450	static int omap1_spi100k_runtime_suspend(struct device *dev)
	451	{
	452	struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
	453	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	454
	455	clk_disable_unprepare(spi100k->ick);
	456	clk_disable_unprepare(spi100k->fck);
	457
	458	return 0;
	459	}
	460
	461	static int omap1_spi100k_runtime_resume(struct device *dev)
	462	{
	463	struct spi_master *master = spi_master_get(dev_get_drvdata(dev));
	464	struct omap1_spi100k *spi100k = spi_master_get_devdata(master);
	465	int ret;
	466
	467	ret = clk_prepare_enable(spi100k->ick);
	468	if (ret != 0) {
	469	dev_err(dev, "Failed to enable ick: %d\n", ret);
	470	return ret;
	471	}
	472
	473	ret = clk_prepare_enable(spi100k->fck);
	474	if (ret != 0) {
	475	dev_err(dev, "Failed to enable fck: %d\n", ret);
	476	clk_disable_unprepare(spi100k->ick);
	477	return ret;
	478	}
	479
	480	return 0;
	481	}
	482	#endif
	483
	484	static const struct dev_pm_ops omap1_spi100k_pm = {
	485	SET_RUNTIME_PM_OPS(omap1_spi100k_runtime_suspend,
	486	omap1_spi100k_runtime_resume, NULL)
	487	};
	488
35c9049b CM	489	static struct platform_driver omap1_spi100k_driver = {
	490	.driver = {
	491	.name = "omap1_spi100k",
db91841b	492	.pm = &omap1_spi100k_pm,
35c9049b	493	},
2d0c6148	494	.probe = omap1_spi100k_probe,
db91841b	495	.remove = omap1_spi100k_remove,
35c9049b CM	496	};
35c9049b CM	497
2d0c6148	498	module_platform_driver(omap1_spi100k_driver);
35c9049b CM	499
	500	MODULE_DESCRIPTION("OMAP7xx SPI 100k controller driver");
	501	MODULE_AUTHOR("Fabrice Crohas <[email protected]>");
	502	MODULE_LICENSE("GPL");