[linux.git] / drivers / spi / spi-sirf.c

/*
 * SPI bus driver for CSR SiRFprimaII
 *
 * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
 *
 * Licensed under GPLv2 or later.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/of_gpio.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi_bitbang.h>
#include <linux/pinctrl/consumer.h>

#define DRIVER_NAME "sirfsoc_spi"

#define SIRFSOC_SPI_CTRL		0x0000
#define SIRFSOC_SPI_CMD			0x0004
#define SIRFSOC_SPI_TX_RX_EN		0x0008
#define SIRFSOC_SPI_INT_EN		0x000C
#define SIRFSOC_SPI_INT_STATUS		0x0010
#define SIRFSOC_SPI_TX_DMA_IO_CTRL	0x0100
#define SIRFSOC_SPI_TX_DMA_IO_LEN	0x0104
#define SIRFSOC_SPI_TXFIFO_CTRL		0x0108
#define SIRFSOC_SPI_TXFIFO_LEVEL_CHK	0x010C
#define SIRFSOC_SPI_TXFIFO_OP		0x0110
#define SIRFSOC_SPI_TXFIFO_STATUS	0x0114
#define SIRFSOC_SPI_TXFIFO_DATA		0x0118
#define SIRFSOC_SPI_RX_DMA_IO_CTRL	0x0120
#define SIRFSOC_SPI_RX_DMA_IO_LEN	0x0124
#define SIRFSOC_SPI_RXFIFO_CTRL		0x0128
#define SIRFSOC_SPI_RXFIFO_LEVEL_CHK	0x012C
#define SIRFSOC_SPI_RXFIFO_OP		0x0130
#define SIRFSOC_SPI_RXFIFO_STATUS	0x0134
#define SIRFSOC_SPI_RXFIFO_DATA		0x0138
#define SIRFSOC_SPI_DUMMY_DELAY_CTL	0x0144

/* SPI CTRL register defines */
#define SIRFSOC_SPI_SLV_MODE		BIT(16)
#define SIRFSOC_SPI_CMD_MODE		BIT(17)
#define SIRFSOC_SPI_CS_IO_OUT		BIT(18)
#define SIRFSOC_SPI_CS_IO_MODE		BIT(19)
#define SIRFSOC_SPI_CLK_IDLE_STAT	BIT(20)
#define SIRFSOC_SPI_CS_IDLE_STAT	BIT(21)
#define SIRFSOC_SPI_TRAN_MSB		BIT(22)
#define SIRFSOC_SPI_DRV_POS_EDGE	BIT(23)
#define SIRFSOC_SPI_CS_HOLD_TIME	BIT(24)
#define SIRFSOC_SPI_CLK_SAMPLE_MODE	BIT(25)
#define SIRFSOC_SPI_TRAN_DAT_FORMAT_8	(0 << 26)
#define SIRFSOC_SPI_TRAN_DAT_FORMAT_12	(1 << 26)
#define SIRFSOC_SPI_TRAN_DAT_FORMAT_16	(2 << 26)
#define SIRFSOC_SPI_TRAN_DAT_FORMAT_32	(3 << 26)
#define SIRFSOC_SPI_CMD_BYTE_NUM(x)		((x & 3) << 28)
#define SIRFSOC_SPI_ENA_AUTO_CLR		BIT(30)
#define SIRFSOC_SPI_MUL_DAT_MODE		BIT(31)

/* Interrupt Enable */
#define SIRFSOC_SPI_RX_DONE_INT_EN		BIT(0)
#define SIRFSOC_SPI_TX_DONE_INT_EN		BIT(1)
#define SIRFSOC_SPI_RX_OFLOW_INT_EN		BIT(2)
#define SIRFSOC_SPI_TX_UFLOW_INT_EN		BIT(3)
#define SIRFSOC_SPI_RX_IO_DMA_INT_EN	BIT(4)
#define SIRFSOC_SPI_TX_IO_DMA_INT_EN	BIT(5)
#define SIRFSOC_SPI_RXFIFO_FULL_INT_EN	BIT(6)
#define SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN	BIT(7)
#define SIRFSOC_SPI_RXFIFO_THD_INT_EN	BIT(8)
#define SIRFSOC_SPI_TXFIFO_THD_INT_EN	BIT(9)
#define SIRFSOC_SPI_FRM_END_INT_EN	BIT(10)

#define SIRFSOC_SPI_INT_MASK_ALL		0x1FFF

/* Interrupt status */
#define SIRFSOC_SPI_RX_DONE		BIT(0)
#define SIRFSOC_SPI_TX_DONE		BIT(1)
#define SIRFSOC_SPI_RX_OFLOW		BIT(2)
#define SIRFSOC_SPI_TX_UFLOW		BIT(3)
#define SIRFSOC_SPI_RX_FIFO_FULL	BIT(6)
#define SIRFSOC_SPI_TXFIFO_EMPTY	BIT(7)
#define SIRFSOC_SPI_RXFIFO_THD_REACH	BIT(8)
#define SIRFSOC_SPI_TXFIFO_THD_REACH	BIT(9)
#define SIRFSOC_SPI_FRM_END		BIT(10)

/* TX RX enable */
#define SIRFSOC_SPI_RX_EN		BIT(0)
#define SIRFSOC_SPI_TX_EN		BIT(1)
#define SIRFSOC_SPI_CMD_TX_EN		BIT(2)

#define SIRFSOC_SPI_IO_MODE_SEL		BIT(0)
#define SIRFSOC_SPI_RX_DMA_FLUSH	BIT(2)

/* FIFO OPs */
#define SIRFSOC_SPI_FIFO_RESET		BIT(0)
#define SIRFSOC_SPI_FIFO_START		BIT(1)

/* FIFO CTRL */
#define SIRFSOC_SPI_FIFO_WIDTH_BYTE	(0 << 0)
#define SIRFSOC_SPI_FIFO_WIDTH_WORD	(1 << 0)
#define SIRFSOC_SPI_FIFO_WIDTH_DWORD	(2 << 0)

/* FIFO Status */
#define	SIRFSOC_SPI_FIFO_LEVEL_MASK	0xFF
#define SIRFSOC_SPI_FIFO_FULL		BIT(8)
#define SIRFSOC_SPI_FIFO_EMPTY		BIT(9)

/* 256 bytes rx/tx FIFO */
#define SIRFSOC_SPI_FIFO_SIZE		256
#define SIRFSOC_SPI_DAT_FRM_LEN_MAX	(64 * 1024)

#define SIRFSOC_SPI_FIFO_SC(x)		((x) & 0x3F)
#define SIRFSOC_SPI_FIFO_LC(x)		(((x) & 0x3F) << 10)
#define SIRFSOC_SPI_FIFO_HC(x)		(((x) & 0x3F) << 20)
#define SIRFSOC_SPI_FIFO_THD(x)		(((x) & 0xFF) << 2)

struct sirfsoc_spi {
	struct spi_bitbang bitbang;
	struct completion done;

	void __iomem *base;
	u32 ctrl_freq;  /* SPI controller clock speed */
	struct clk *clk;
	struct pinctrl *p;

	/* rx & tx bufs from the spi_transfer */
	const void *tx;
	void *rx;

	/* place received word into rx buffer */
	void (*rx_word) (struct sirfsoc_spi *);
	/* get word from tx buffer for sending */
	void (*tx_word) (struct sirfsoc_spi *);

	/* number of words left to be tranmitted/received */
	unsigned int left_tx_cnt;
	unsigned int left_rx_cnt;

	/* tasklet to push tx msg into FIFO */
	struct tasklet_struct tasklet_tx;

	int chipselect[0];
};

static void spi_sirfsoc_rx_word_u8(struct sirfsoc_spi *sspi)
{
	u32 data;
	u8 *rx = sspi->rx;

	data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);

	if (rx) {
		*rx++ = (u8) data;
		sspi->rx = rx;
	}

	sspi->left_rx_cnt--;
}

static void spi_sirfsoc_tx_word_u8(struct sirfsoc_spi *sspi)
{
	u32 data = 0;
	const u8 *tx = sspi->tx;

	if (tx) {
		data = *tx++;
		sspi->tx = tx;
	}

	writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
	sspi->left_tx_cnt--;
}

static void spi_sirfsoc_rx_word_u16(struct sirfsoc_spi *sspi)
{
	u32 data;
	u16 *rx = sspi->rx;

	data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);

	if (rx) {
		*rx++ = (u16) data;
		sspi->rx = rx;
	}

	sspi->left_rx_cnt--;
}

static void spi_sirfsoc_tx_word_u16(struct sirfsoc_spi *sspi)
{
	u32 data = 0;
	const u16 *tx = sspi->tx;

	if (tx) {
		data = *tx++;
		sspi->tx = tx;
	}

	writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
	sspi->left_tx_cnt--;
}

static void spi_sirfsoc_rx_word_u32(struct sirfsoc_spi *sspi)
{
	u32 data;
	u32 *rx = sspi->rx;

	data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);

	if (rx) {
		*rx++ = (u32) data;
		sspi->rx = rx;
	}

	sspi->left_rx_cnt--;

}

static void spi_sirfsoc_tx_word_u32(struct sirfsoc_spi *sspi)
{
	u32 data = 0;
	const u32 *tx = sspi->tx;

	if (tx) {
		data = *tx++;
		sspi->tx = tx;
	}

	writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
	sspi->left_tx_cnt--;
}

static void spi_sirfsoc_tasklet_tx(unsigned long arg)
{
	struct sirfsoc_spi *sspi = (struct sirfsoc_spi *)arg;

	/* Fill Tx FIFO while there are left words to be transmitted */
	while (!((readl(sspi->base + SIRFSOC_SPI_TXFIFO_STATUS) &
			SIRFSOC_SPI_FIFO_FULL)) &&
			sspi->left_tx_cnt)
		sspi->tx_word(sspi);
}

static irqreturn_t spi_sirfsoc_irq(int irq, void *dev_id)
{
	struct sirfsoc_spi *sspi = dev_id;
	u32 spi_stat = readl(sspi->base + SIRFSOC_SPI_INT_STATUS);

	writel(spi_stat, sspi->base + SIRFSOC_SPI_INT_STATUS);

	/* Error Conditions */
	if (spi_stat & SIRFSOC_SPI_RX_OFLOW ||
			spi_stat & SIRFSOC_SPI_TX_UFLOW) {
		complete(&sspi->done);
		writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
	}

	if (spi_stat & SIRFSOC_SPI_FRM_END) {
		while (!((readl(sspi->base + SIRFSOC_SPI_RXFIFO_STATUS)
				& SIRFSOC_SPI_FIFO_EMPTY)) &&
				sspi->left_rx_cnt)
			sspi->rx_word(sspi);

		/* Received all words */
		if ((sspi->left_rx_cnt == 0) && (sspi->left_tx_cnt == 0)) {
			complete(&sspi->done);
			writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
		}
	}

	if (spi_stat & SIRFSOC_SPI_RXFIFO_THD_REACH ||
		spi_stat & SIRFSOC_SPI_TXFIFO_THD_REACH ||
		spi_stat & SIRFSOC_SPI_RX_FIFO_FULL ||
		spi_stat & SIRFSOC_SPI_TXFIFO_EMPTY)
		tasklet_schedule(&sspi->tasklet_tx);

	return IRQ_HANDLED;
}

static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t)
{
	struct sirfsoc_spi *sspi;
	int timeout = t->len * 10;
	sspi = spi_master_get_devdata(spi->master);

	sspi->tx = t->tx_buf;
	sspi->rx = t->rx_buf;
	sspi->left_tx_cnt = sspi->left_rx_cnt = t->len;
	INIT_COMPLETION(sspi->done);

	writel(SIRFSOC_SPI_INT_MASK_ALL, sspi->base + SIRFSOC_SPI_INT_STATUS);

	if (t->len == 1) {
		writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
			SIRFSOC_SPI_ENA_AUTO_CLR,
			sspi->base + SIRFSOC_SPI_CTRL);
		writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
		writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
	} else if ((t->len > 1) && (t->len < SIRFSOC_SPI_DAT_FRM_LEN_MAX)) {
		writel(readl(sspi->base + SIRFSOC_SPI_CTRL) |
				SIRFSOC_SPI_MUL_DAT_MODE |
				SIRFSOC_SPI_ENA_AUTO_CLR,
			sspi->base + SIRFSOC_SPI_CTRL);
		writel(t->len - 1, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
		writel(t->len - 1, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
	} else {
		writel(readl(sspi->base + SIRFSOC_SPI_CTRL),
			sspi->base + SIRFSOC_SPI_CTRL);
		writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
		writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
	}

	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);

	/* Send the first word to trigger the whole tx/rx process */
	sspi->tx_word(sspi);

	writel(SIRFSOC_SPI_RX_OFLOW_INT_EN | SIRFSOC_SPI_TX_UFLOW_INT_EN |
		SIRFSOC_SPI_RXFIFO_THD_INT_EN | SIRFSOC_SPI_TXFIFO_THD_INT_EN |
		SIRFSOC_SPI_FRM_END_INT_EN | SIRFSOC_SPI_RXFIFO_FULL_INT_EN |
		SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN, sspi->base + SIRFSOC_SPI_INT_EN);
	writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN, sspi->base + SIRFSOC_SPI_TX_RX_EN);

	if (wait_for_completion_timeout(&sspi->done, timeout) == 0)
		dev_err(&spi->dev, "transfer timeout\n");

	/* TX, RX FIFO stop */
	writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
	writel(0, sspi->base + SIRFSOC_SPI_TX_RX_EN);
	writel(0, sspi->base + SIRFSOC_SPI_INT_EN);

	return t->len - sspi->left_rx_cnt;
}

static void spi_sirfsoc_chipselect(struct spi_device *spi, int value)
{
	struct sirfsoc_spi *sspi = spi_master_get_devdata(spi->master);

	if (sspi->chipselect[spi->chip_select] == 0) {
		u32 regval = readl(sspi->base + SIRFSOC_SPI_CTRL);
		regval |= SIRFSOC_SPI_CS_IO_OUT;
		switch (value) {
		case BITBANG_CS_ACTIVE:
			if (spi->mode & SPI_CS_HIGH)
				regval |= SIRFSOC_SPI_CS_IO_OUT;
			else
				regval &= ~SIRFSOC_SPI_CS_IO_OUT;
			break;
		case BITBANG_CS_INACTIVE:
			if (spi->mode & SPI_CS_HIGH)
				regval &= ~SIRFSOC_SPI_CS_IO_OUT;
			else
				regval |= SIRFSOC_SPI_CS_IO_OUT;
			break;
		}
		writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
	} else {
		int gpio = sspi->chipselect[spi->chip_select];
		gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
	}
}

static int
spi_sirfsoc_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
{
	struct sirfsoc_spi *sspi;
	u8 bits_per_word = 0;
	int hz = 0;
	u32 regval;
	u32 txfifo_ctrl, rxfifo_ctrl;
	u32 fifo_size = SIRFSOC_SPI_FIFO_SIZE / 4;

	sspi = spi_master_get_devdata(spi->master);

	bits_per_word = t && t->bits_per_word ? t->bits_per_word :
		spi->bits_per_word;
	hz = t && t->speed_hz ? t->speed_hz : spi->max_speed_hz;

	/* Enable IO mode for RX, TX */
	writel(SIRFSOC_SPI_IO_MODE_SEL, sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL);
	writel(SIRFSOC_SPI_IO_MODE_SEL, sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL);
	regval = (sspi->ctrl_freq / (2 * hz)) - 1;

	if (regval > 0xFFFF || regval < 0) {
		dev_err(&spi->dev, "Speed %d not supported\n", hz);
		return -EINVAL;
	}

	switch (bits_per_word) {
	case 8:
		regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_8;
		sspi->rx_word = spi_sirfsoc_rx_word_u8;
		sspi->tx_word = spi_sirfsoc_tx_word_u8;
		txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
					SIRFSOC_SPI_FIFO_WIDTH_BYTE;
		rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
					SIRFSOC_SPI_FIFO_WIDTH_BYTE;
		break;
	case 12:
	case 16:
		regval |= (bits_per_word ==  12) ? SIRFSOC_SPI_TRAN_DAT_FORMAT_12 :
			SIRFSOC_SPI_TRAN_DAT_FORMAT_16;
		sspi->rx_word = spi_sirfsoc_rx_word_u16;
		sspi->tx_word = spi_sirfsoc_tx_word_u16;
		txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
					SIRFSOC_SPI_FIFO_WIDTH_WORD;
		rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
					SIRFSOC_SPI_FIFO_WIDTH_WORD;
		break;
	case 32:
		regval |= SIRFSOC_SPI_TRAN_DAT_FORMAT_32;
		sspi->rx_word = spi_sirfsoc_rx_word_u32;
		sspi->tx_word = spi_sirfsoc_tx_word_u32;
		txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
					SIRFSOC_SPI_FIFO_WIDTH_DWORD;
		rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) |
					SIRFSOC_SPI_FIFO_WIDTH_DWORD;
		break;
	default:
		dev_err(&spi->dev, "Bits per word %d not supported\n",
		       bits_per_word);
		return -EINVAL;
	}

	if (!(spi->mode & SPI_CS_HIGH))
		regval |= SIRFSOC_SPI_CS_IDLE_STAT;
	if (!(spi->mode & SPI_LSB_FIRST))
		regval |= SIRFSOC_SPI_TRAN_MSB;
	if (spi->mode & SPI_CPOL)
		regval |= SIRFSOC_SPI_CLK_IDLE_STAT;

	/*
	 * Data should be driven at least 1/2 cycle before the fetch edge to make
	 * sure that data gets stable at the fetch edge.
	 */
	if (((spi->mode & SPI_CPOL) && (spi->mode & SPI_CPHA)) ||
	    (!(spi->mode & SPI_CPOL) && !(spi->mode & SPI_CPHA)))
		regval &= ~SIRFSOC_SPI_DRV_POS_EDGE;
	else
		regval |= SIRFSOC_SPI_DRV_POS_EDGE;

	writel(SIRFSOC_SPI_FIFO_SC(fifo_size - 2) |
			SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
			SIRFSOC_SPI_FIFO_HC(2),
		sspi->base + SIRFSOC_SPI_TXFIFO_LEVEL_CHK);
	writel(SIRFSOC_SPI_FIFO_SC(2) |
			SIRFSOC_SPI_FIFO_LC(fifo_size / 2) |
			SIRFSOC_SPI_FIFO_HC(fifo_size - 2),
		sspi->base + SIRFSOC_SPI_RXFIFO_LEVEL_CHK);
	writel(txfifo_ctrl, sspi->base + SIRFSOC_SPI_TXFIFO_CTRL);
	writel(rxfifo_ctrl, sspi->base + SIRFSOC_SPI_RXFIFO_CTRL);

	writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
	return 0;
}

static int spi_sirfsoc_setup(struct spi_device *spi)
{
	struct sirfsoc_spi *sspi;

	if (!spi->max_speed_hz)
		return -EINVAL;

	sspi = spi_master_get_devdata(spi->master);

	if (!spi->bits_per_word)
		spi->bits_per_word = 8;

	return spi_sirfsoc_setup_transfer(spi, NULL);
}

static int __devinit spi_sirfsoc_probe(struct platform_device *pdev)
{
	struct sirfsoc_spi *sspi;
	struct spi_master *master;
	struct resource *mem_res;
	int num_cs, cs_gpio, irq;
	int i;
	int ret;

	ret = of_property_read_u32(pdev->dev.of_node,
			"sirf,spi-num-chipselects", &num_cs);
	if (ret < 0) {
		dev_err(&pdev->dev, "Unable to get chip select number\n");
		goto err_cs;
	}

	master = spi_alloc_master(&pdev->dev, sizeof(*sspi) + sizeof(int) * num_cs);
	if (!master) {
		dev_err(&pdev->dev, "Unable to allocate SPI master\n");
		return -ENOMEM;
	}
	platform_set_drvdata(pdev, master);
	sspi = spi_master_get_devdata(master);

	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem_res) {
		dev_err(&pdev->dev, "Unable to get IO resource\n");
		ret = -ENODEV;
		goto free_master;
	}
	master->num_chipselect = num_cs;

	for (i = 0; i < master->num_chipselect; i++) {
		cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", i);
		if (cs_gpio < 0) {
			dev_err(&pdev->dev, "can't get cs gpio from DT\n");
			ret = -ENODEV;
			goto free_master;
		}

		sspi->chipselect[i] = cs_gpio;
		if (cs_gpio == 0)
			continue; /* use cs from spi controller */

		ret = gpio_request(cs_gpio, DRIVER_NAME);
		if (ret) {
			while (i > 0) {
				i--;
				if (sspi->chipselect[i] > 0)
					gpio_free(sspi->chipselect[i]);
			}
			dev_err(&pdev->dev, "fail to request cs gpios\n");
			goto free_master;
		}
	}

	sspi->base = devm_request_and_ioremap(&pdev->dev, mem_res);
	if (!sspi->base) {
		dev_err(&pdev->dev, "IO remap failed!\n");
		ret = -ENOMEM;
		goto free_master;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		ret = -ENXIO;
		goto free_master;
	}
	ret = devm_request_irq(&pdev->dev, irq, spi_sirfsoc_irq, 0,
				DRIVER_NAME, sspi);
	if (ret)
		goto free_master;

	sspi->bitbang.master = spi_master_get(master);
	sspi->bitbang.chipselect = spi_sirfsoc_chipselect;
	sspi->bitbang.setup_transfer = spi_sirfsoc_setup_transfer;
	sspi->bitbang.txrx_bufs = spi_sirfsoc_transfer;
	sspi->bitbang.master->setup = spi_sirfsoc_setup;
	master->bus_num = pdev->id;
	sspi->bitbang.master->dev.of_node = pdev->dev.of_node;

	sspi->p = pinctrl_get_select_default(&pdev->dev);
	ret = IS_ERR(sspi->p);
	if (ret)
		goto free_master;

	sspi->clk = clk_get(&pdev->dev, NULL);
	if (IS_ERR(sspi->clk)) {
		ret = -EINVAL;
		goto free_pin;
	}
	clk_enable(sspi->clk);
	sspi->ctrl_freq = clk_get_rate(sspi->clk);

	init_completion(&sspi->done);

	tasklet_init(&sspi->tasklet_tx, spi_sirfsoc_tasklet_tx,
		     (unsigned long)sspi);

	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
	/* We are not using dummy delay between command and data */
	writel(0, sspi->base + SIRFSOC_SPI_DUMMY_DELAY_CTL);

	ret = spi_bitbang_start(&sspi->bitbang);
	if (ret)
		goto free_clk;

	dev_info(&pdev->dev, "registerred, bus number = %d\n", master->bus_num);

	return 0;

free_clk:
	clk_disable(sspi->clk);
	clk_put(sspi->clk);
free_pin:
	pinctrl_put(sspi->p);
free_master:
	spi_master_put(master);
err_cs:
	return ret;
}

static int  __devexit spi_sirfsoc_remove(struct platform_device *pdev)
{
	struct spi_master *master;
	struct sirfsoc_spi *sspi;
	int i;

	master = platform_get_drvdata(pdev);
	sspi = spi_master_get_devdata(master);

	spi_bitbang_stop(&sspi->bitbang);
	for (i = 0; i < master->num_chipselect; i++) {
		if (sspi->chipselect[i] > 0)
			gpio_free(sspi->chipselect[i]);
	}
	clk_disable(sspi->clk);
	clk_put(sspi->clk);
	pinctrl_put(sspi->p);
	spi_master_put(master);
	return 0;
}

#ifdef CONFIG_PM
static int spi_sirfsoc_suspend(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct spi_master *master = platform_get_drvdata(pdev);
	struct sirfsoc_spi *sspi = spi_master_get_devdata(master);

	clk_disable(sspi->clk);
	return 0;
}

static int spi_sirfsoc_resume(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct spi_master *master = platform_get_drvdata(pdev);
	struct sirfsoc_spi *sspi = spi_master_get_devdata(master);

	clk_enable(sspi->clk);
	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);

	return 0;
}

static const struct dev_pm_ops spi_sirfsoc_pm_ops = {
	.suspend = spi_sirfsoc_suspend,
	.resume = spi_sirfsoc_resume,
};
#endif

static const struct of_device_id spi_sirfsoc_of_match[] = {
	{ .compatible = "sirf,prima2-spi", },
	{}
};
MODULE_DEVICE_TABLE(of, sirfsoc_spi_of_match);

static struct platform_driver spi_sirfsoc_driver = {
	.driver = {
		.name = DRIVER_NAME,
		.owner = THIS_MODULE,
#ifdef CONFIG_PM
		.pm     = &spi_sirfsoc_pm_ops,
#endif
		.of_match_table = spi_sirfsoc_of_match,
	},
	.probe = spi_sirfsoc_probe,
	.remove = __devexit_p(spi_sirfsoc_remove),
};
module_platform_driver(spi_sirfsoc_driver);

MODULE_DESCRIPTION("SiRF SoC SPI master driver");
MODULE_AUTHOR("Zhiwu Song <[email protected]>, "
		"Barry Song <[email protected]>");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
1cc2df9d ZS	1	/*
	2	* SPI bus driver for CSR SiRFprimaII
	3	*
	4	* Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
	5	*
	6	* Licensed under GPLv2 or later.
	7	*/
	8
	9	#include <linux/module.h>
	10	#include <linux/kernel.h>
	11	#include <linux/slab.h>
	12	#include <linux/clk.h>
	13	#include <linux/interrupt.h>
	14	#include <linux/io.h>
	15	#include <linux/of.h>
	16	#include <linux/bitops.h>
	17	#include <linux/err.h>
	18	#include <linux/platform_device.h>
	19	#include <linux/of_gpio.h>
	20	#include <linux/spi/spi.h>
	21	#include <linux/spi/spi_bitbang.h>
71422f9e	22	#include <linux/pinctrl/consumer.h>
1cc2df9d ZS	23
	24	#define DRIVER_NAME "sirfsoc_spi"
	25
	26	#define SIRFSOC_SPI_CTRL 0x0000
	27	#define SIRFSOC_SPI_CMD 0x0004
	28	#define SIRFSOC_SPI_TX_RX_EN 0x0008
	29	#define SIRFSOC_SPI_INT_EN 0x000C
	30	#define SIRFSOC_SPI_INT_STATUS 0x0010
	31	#define SIRFSOC_SPI_TX_DMA_IO_CTRL 0x0100
	32	#define SIRFSOC_SPI_TX_DMA_IO_LEN 0x0104
	33	#define SIRFSOC_SPI_TXFIFO_CTRL 0x0108
	34	#define SIRFSOC_SPI_TXFIFO_LEVEL_CHK 0x010C
	35	#define SIRFSOC_SPI_TXFIFO_OP 0x0110
	36	#define SIRFSOC_SPI_TXFIFO_STATUS 0x0114
	37	#define SIRFSOC_SPI_TXFIFO_DATA 0x0118
	38	#define SIRFSOC_SPI_RX_DMA_IO_CTRL 0x0120
	39	#define SIRFSOC_SPI_RX_DMA_IO_LEN 0x0124
	40	#define SIRFSOC_SPI_RXFIFO_CTRL 0x0128
	41	#define SIRFSOC_SPI_RXFIFO_LEVEL_CHK 0x012C
	42	#define SIRFSOC_SPI_RXFIFO_OP 0x0130
	43	#define SIRFSOC_SPI_RXFIFO_STATUS 0x0134
	44	#define SIRFSOC_SPI_RXFIFO_DATA 0x0138
	45	#define SIRFSOC_SPI_DUMMY_DELAY_CTL 0x0144
	46
	47	/* SPI CTRL register defines */
	48	#define SIRFSOC_SPI_SLV_MODE BIT(16)
	49	#define SIRFSOC_SPI_CMD_MODE BIT(17)
	50	#define SIRFSOC_SPI_CS_IO_OUT BIT(18)
	51	#define SIRFSOC_SPI_CS_IO_MODE BIT(19)
	52	#define SIRFSOC_SPI_CLK_IDLE_STAT BIT(20)
	53	#define SIRFSOC_SPI_CS_IDLE_STAT BIT(21)
	54	#define SIRFSOC_SPI_TRAN_MSB BIT(22)
	55	#define SIRFSOC_SPI_DRV_POS_EDGE BIT(23)
	56	#define SIRFSOC_SPI_CS_HOLD_TIME BIT(24)
	57	#define SIRFSOC_SPI_CLK_SAMPLE_MODE BIT(25)
	58	#define SIRFSOC_SPI_TRAN_DAT_FORMAT_8 (0 << 26)
	59	#define SIRFSOC_SPI_TRAN_DAT_FORMAT_12 (1 << 26)
	60	#define SIRFSOC_SPI_TRAN_DAT_FORMAT_16 (2 << 26)
	61	#define SIRFSOC_SPI_TRAN_DAT_FORMAT_32 (3 << 26)
	62	#define SIRFSOC_SPI_CMD_BYTE_NUM(x) ((x & 3) << 28)
	63	#define SIRFSOC_SPI_ENA_AUTO_CLR BIT(30)
	64	#define SIRFSOC_SPI_MUL_DAT_MODE BIT(31)
	65
	66	/* Interrupt Enable */
	67	#define SIRFSOC_SPI_RX_DONE_INT_EN BIT(0)
	68	#define SIRFSOC_SPI_TX_DONE_INT_EN BIT(1)
	69	#define SIRFSOC_SPI_RX_OFLOW_INT_EN BIT(2)
	70	#define SIRFSOC_SPI_TX_UFLOW_INT_EN BIT(3)
	71	#define SIRFSOC_SPI_RX_IO_DMA_INT_EN BIT(4)
	72	#define SIRFSOC_SPI_TX_IO_DMA_INT_EN BIT(5)
	73	#define SIRFSOC_SPI_RXFIFO_FULL_INT_EN BIT(6)
	74	#define SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN BIT(7)
	75	#define SIRFSOC_SPI_RXFIFO_THD_INT_EN BIT(8)
	76	#define SIRFSOC_SPI_TXFIFO_THD_INT_EN BIT(9)
	77	#define SIRFSOC_SPI_FRM_END_INT_EN BIT(10)
	78
	79	#define SIRFSOC_SPI_INT_MASK_ALL 0x1FFF
	80
	81	/* Interrupt status */
	82	#define SIRFSOC_SPI_RX_DONE BIT(0)
	83	#define SIRFSOC_SPI_TX_DONE BIT(1)
	84	#define SIRFSOC_SPI_RX_OFLOW BIT(2)
	85	#define SIRFSOC_SPI_TX_UFLOW BIT(3)
	86	#define SIRFSOC_SPI_RX_FIFO_FULL BIT(6)
87	#define SIRFSOC_SPI_TXFIFO_EMPTY BIT(7)
88	#define SIRFSOC_SPI_RXFIFO_THD_REACH BIT(8)
89	#define SIRFSOC_SPI_TXFIFO_THD_REACH BIT(9)
90	#define SIRFSOC_SPI_FRM_END BIT(10)
91
92	/* TX RX enable */
93	#define SIRFSOC_SPI_RX_EN BIT(0)
94	#define SIRFSOC_SPI_TX_EN BIT(1)
95	#define SIRFSOC_SPI_CMD_TX_EN BIT(2)
96
97	#define SIRFSOC_SPI_IO_MODE_SEL BIT(0)
98	#define SIRFSOC_SPI_RX_DMA_FLUSH BIT(2)
99
100	/* FIFO OPs */
101	#define SIRFSOC_SPI_FIFO_RESET BIT(0)
102	#define SIRFSOC_SPI_FIFO_START BIT(1)
103
104	/* FIFO CTRL */
105	#define SIRFSOC_SPI_FIFO_WIDTH_BYTE (0 << 0)
106	#define SIRFSOC_SPI_FIFO_WIDTH_WORD (1 << 0)
107	#define SIRFSOC_SPI_FIFO_WIDTH_DWORD (2 << 0)
108
109	/* FIFO Status */
110	#define SIRFSOC_SPI_FIFO_LEVEL_MASK 0xFF
111	#define SIRFSOC_SPI_FIFO_FULL BIT(8)
112	#define SIRFSOC_SPI_FIFO_EMPTY BIT(9)
113
114	/* 256 bytes rx/tx FIFO */
115	#define SIRFSOC_SPI_FIFO_SIZE 256
116	#define SIRFSOC_SPI_DAT_FRM_LEN_MAX (64 * 1024)
117
118	#define SIRFSOC_SPI_FIFO_SC(x) ((x) & 0x3F)
119	#define SIRFSOC_SPI_FIFO_LC(x) (((x) & 0x3F) << 10)
120	#define SIRFSOC_SPI_FIFO_HC(x) (((x) & 0x3F) << 20)
121	#define SIRFSOC_SPI_FIFO_THD(x) (((x) & 0xFF) << 2)
122
123	struct sirfsoc_spi {
124	struct spi_bitbang bitbang;
125	struct completion done;
126
127	void __iomem *base;
128	u32 ctrl_freq; /* SPI controller clock speed */
129	struct clk *clk;
71422f9e	130	struct pinctrl *p;
1cc2df9d ZS	131
	132	/* rx & tx bufs from the spi_transfer */
	133	const void *tx;
	134	void *rx;
	135
	136	/* place received word into rx buffer */
	137	void (rx_word) (struct sirfsoc_spi );
	138	/* get word from tx buffer for sending */
	139	void (tx_word) (struct sirfsoc_spi );
	140
	141	/* number of words left to be tranmitted/received */
	142	unsigned int left_tx_cnt;
	143	unsigned int left_rx_cnt;
	144
	145	/* tasklet to push tx msg into FIFO */
	146	struct tasklet_struct tasklet_tx;
	147
	148	int chipselect[0];
	149	};
	150
	151	static void spi_sirfsoc_rx_word_u8(struct sirfsoc_spi *sspi)
	152	{
	153	u32 data;
	154	u8 *rx = sspi->rx;
	155
	156	data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
	157
	158	if (rx) {
	159	*rx++ = (u8) data;
	160	sspi->rx = rx;
	161	}
	162
	163	sspi->left_rx_cnt--;
	164	}
	165
	166	static void spi_sirfsoc_tx_word_u8(struct sirfsoc_spi *sspi)
	167	{
	168	u32 data = 0;
	169	const u8 *tx = sspi->tx;
	170
	171	if (tx) {
	172	data = *tx++;
	173	sspi->tx = tx;
	174	}
	175
	176	writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
	177	sspi->left_tx_cnt--;
	178	}
	179
	180	static void spi_sirfsoc_rx_word_u16(struct sirfsoc_spi *sspi)
	181	{
	182	u32 data;
	183	u16 *rx = sspi->rx;
	184
	185	data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
	186
	187	if (rx) {
	188	*rx++ = (u16) data;
	189	sspi->rx = rx;
	190	}
	191
	192	sspi->left_rx_cnt--;
	193	}
	194
195	static void spi_sirfsoc_tx_word_u16(struct sirfsoc_spi *sspi)
196	{
197	u32 data = 0;
198	const u16 *tx = sspi->tx;
199
200	if (tx) {
201	data = *tx++;
202	sspi->tx = tx;
203	}
204
205	writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
206	sspi->left_tx_cnt--;
207	}
208
209	static void spi_sirfsoc_rx_word_u32(struct sirfsoc_spi *sspi)
210	{
211	u32 data;
212	u32 *rx = sspi->rx;
213
214	data = readl(sspi->base + SIRFSOC_SPI_RXFIFO_DATA);
215
216	if (rx) {
217	*rx++ = (u32) data;
218	sspi->rx = rx;
219	}
220
221	sspi->left_rx_cnt--;
222
223	}
224
225	static void spi_sirfsoc_tx_word_u32(struct sirfsoc_spi *sspi)
226	{
227	u32 data = 0;
228	const u32 *tx = sspi->tx;
229
230	if (tx) {
231	data = *tx++;
232	sspi->tx = tx;
233	}
234
235	writel(data, sspi->base + SIRFSOC_SPI_TXFIFO_DATA);
236	sspi->left_tx_cnt--;
237	}
238
239	static void spi_sirfsoc_tasklet_tx(unsigned long arg)
240	{
241	struct sirfsoc_spi sspi = (struct sirfsoc_spi )arg;
242
243	/* Fill Tx FIFO while there are left words to be transmitted */
244	while (!((readl(sspi->base + SIRFSOC_SPI_TXFIFO_STATUS) &
245	SIRFSOC_SPI_FIFO_FULL)) &&
246	sspi->left_tx_cnt)
247	sspi->tx_word(sspi);
248	}
249
250	static irqreturn_t spi_sirfsoc_irq(int irq, void *dev_id)
251	{
252	struct sirfsoc_spi *sspi = dev_id;
253	u32 spi_stat = readl(sspi->base + SIRFSOC_SPI_INT_STATUS);
254
255	writel(spi_stat, sspi->base + SIRFSOC_SPI_INT_STATUS);
256
257	/* Error Conditions */
258	if (spi_stat & SIRFSOC_SPI_RX_OFLOW \|\|
259	spi_stat & SIRFSOC_SPI_TX_UFLOW) {
260	complete(&sspi->done);
261	writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
262	}
263
264	if (spi_stat & SIRFSOC_SPI_FRM_END) {
265	while (!((readl(sspi->base + SIRFSOC_SPI_RXFIFO_STATUS)
266	& SIRFSOC_SPI_FIFO_EMPTY)) &&
267	sspi->left_rx_cnt)
268	sspi->rx_word(sspi);
269
270	/* Received all words */
271	if ((sspi->left_rx_cnt == 0) && (sspi->left_tx_cnt == 0)) {
272	complete(&sspi->done);
273	writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN);
274	}
275	}
276
277	if (spi_stat & SIRFSOC_SPI_RXFIFO_THD_REACH \|\|
278	spi_stat & SIRFSOC_SPI_TXFIFO_THD_REACH \|\|
279	spi_stat & SIRFSOC_SPI_RX_FIFO_FULL \|\|
280	spi_stat & SIRFSOC_SPI_TXFIFO_EMPTY)
281	tasklet_schedule(&sspi->tasklet_tx);
282
283	return IRQ_HANDLED;
284	}
285
286	static int spi_sirfsoc_transfer(struct spi_device spi, struct spi_transfer t)
287	{
288	struct sirfsoc_spi *sspi;
289	int timeout = t->len * 10;
290	sspi = spi_master_get_devdata(spi->master);
291
292	sspi->tx = t->tx_buf;
293	sspi->rx = t->rx_buf;
294	sspi->left_tx_cnt = sspi->left_rx_cnt = t->len;
295	INIT_COMPLETION(sspi->done);
296
297	writel(SIRFSOC_SPI_INT_MASK_ALL, sspi->base + SIRFSOC_SPI_INT_STATUS);
298
299	if (t->len == 1) {
300	writel(readl(sspi->base + SIRFSOC_SPI_CTRL) \|
301	SIRFSOC_SPI_ENA_AUTO_CLR,
302	sspi->base + SIRFSOC_SPI_CTRL);
303	writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
304	writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
305	} else if ((t->len > 1) && (t->len < SIRFSOC_SPI_DAT_FRM_LEN_MAX)) {
306	writel(readl(sspi->base + SIRFSOC_SPI_CTRL) \|
307	SIRFSOC_SPI_MUL_DAT_MODE \|
308	SIRFSOC_SPI_ENA_AUTO_CLR,
309	sspi->base + SIRFSOC_SPI_CTRL);
310	writel(t->len - 1, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
311	writel(t->len - 1, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
312	} else {
313	writel(readl(sspi->base + SIRFSOC_SPI_CTRL),
314	sspi->base + SIRFSOC_SPI_CTRL);
315	writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN);
316	writel(0, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN);
317	}
318
319	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
320	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
321	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
322	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
323
324	/* Send the first word to trigger the whole tx/rx process */
325	sspi->tx_word(sspi);
326
327	writel(SIRFSOC_SPI_RX_OFLOW_INT_EN \| SIRFSOC_SPI_TX_UFLOW_INT_EN \|
328	SIRFSOC_SPI_RXFIFO_THD_INT_EN \| SIRFSOC_SPI_TXFIFO_THD_INT_EN \|
329	SIRFSOC_SPI_FRM_END_INT_EN \| SIRFSOC_SPI_RXFIFO_FULL_INT_EN \|
330	SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN, sspi->base + SIRFSOC_SPI_INT_EN);
331	writel(SIRFSOC_SPI_RX_EN \| SIRFSOC_SPI_TX_EN, sspi->base + SIRFSOC_SPI_TX_RX_EN);
332
333	if (wait_for_completion_timeout(&sspi->done, timeout) == 0)
334	dev_err(&spi->dev, "transfer timeout\n");
335
336	/* TX, RX FIFO stop */
337	writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
338	writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
339	writel(0, sspi->base + SIRFSOC_SPI_TX_RX_EN);
340	writel(0, sspi->base + SIRFSOC_SPI_INT_EN);
341
342	return t->len - sspi->left_rx_cnt;
343	}
344
345	static void spi_sirfsoc_chipselect(struct spi_device *spi, int value)
346	{
347	struct sirfsoc_spi *sspi = spi_master_get_devdata(spi->master);
348
349	if (sspi->chipselect[spi->chip_select] == 0) {
350	u32 regval = readl(sspi->base + SIRFSOC_SPI_CTRL);
351	regval \|= SIRFSOC_SPI_CS_IO_OUT;
352	switch (value) {
353	case BITBANG_CS_ACTIVE:
354	if (spi->mode & SPI_CS_HIGH)
355	regval \|= SIRFSOC_SPI_CS_IO_OUT;
356	else
357	regval &= ~SIRFSOC_SPI_CS_IO_OUT;
358	break;
359	case BITBANG_CS_INACTIVE:
360	if (spi->mode & SPI_CS_HIGH)
361	regval &= ~SIRFSOC_SPI_CS_IO_OUT;
362	else
363	regval \|= SIRFSOC_SPI_CS_IO_OUT;
364	break;
365	}
366	writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
367	} else {
368	int gpio = sspi->chipselect[spi->chip_select];
369	gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
370	}
371	}
372
373	static int
374	spi_sirfsoc_setup_transfer(struct spi_device spi, struct spi_transfer t)
375	{
376	struct sirfsoc_spi *sspi;
377	u8 bits_per_word = 0;
378	int hz = 0;
379	u32 regval;
380	u32 txfifo_ctrl, rxfifo_ctrl;
381	u32 fifo_size = SIRFSOC_SPI_FIFO_SIZE / 4;
382
383	sspi = spi_master_get_devdata(spi->master);
384
385	bits_per_word = t && t->bits_per_word ? t->bits_per_word :
386	spi->bits_per_word;
387	hz = t && t->speed_hz ? t->speed_hz : spi->max_speed_hz;
388
389	/* Enable IO mode for RX, TX */
390	writel(SIRFSOC_SPI_IO_MODE_SEL, sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL);
391	writel(SIRFSOC_SPI_IO_MODE_SEL, sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL);
392	regval = (sspi->ctrl_freq / (2 * hz)) - 1;
393
394	if (regval > 0xFFFF \|\| regval < 0) {
395	dev_err(&spi->dev, "Speed %d not supported\n", hz);
396	return -EINVAL;
397	}
398
399	switch (bits_per_word) {
400	case 8:
401	regval \|= SIRFSOC_SPI_TRAN_DAT_FORMAT_8;
402	sspi->rx_word = spi_sirfsoc_rx_word_u8;
403	sspi->tx_word = spi_sirfsoc_tx_word_u8;
404	txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) \|
405	SIRFSOC_SPI_FIFO_WIDTH_BYTE;
406	rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) \|
407	SIRFSOC_SPI_FIFO_WIDTH_BYTE;
408	break;
409	case 12:
410	case 16:
411	regval \|= (bits_per_word == 12) ? SIRFSOC_SPI_TRAN_DAT_FORMAT_12 :
412	SIRFSOC_SPI_TRAN_DAT_FORMAT_16;
413	sspi->rx_word = spi_sirfsoc_rx_word_u16;
414	sspi->tx_word = spi_sirfsoc_tx_word_u16;
415	txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) \|
416	SIRFSOC_SPI_FIFO_WIDTH_WORD;
417	rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) \|
418	SIRFSOC_SPI_FIFO_WIDTH_WORD;
419	break;
420	case 32:
421	regval \|= SIRFSOC_SPI_TRAN_DAT_FORMAT_32;
422	sspi->rx_word = spi_sirfsoc_rx_word_u32;
423	sspi->tx_word = spi_sirfsoc_tx_word_u32;
424	txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) \|
425	SIRFSOC_SPI_FIFO_WIDTH_DWORD;
426	rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) \|
427	SIRFSOC_SPI_FIFO_WIDTH_DWORD;
428	break;
429	default:
430	dev_err(&spi->dev, "Bits per word %d not supported\n",
431	bits_per_word);
432	return -EINVAL;
433	}
434
435	if (!(spi->mode & SPI_CS_HIGH))
436	regval \|= SIRFSOC_SPI_CS_IDLE_STAT;
437	if (!(spi->mode & SPI_LSB_FIRST))
438	regval \|= SIRFSOC_SPI_TRAN_MSB;
439	if (spi->mode & SPI_CPOL)
440	regval \|= SIRFSOC_SPI_CLK_IDLE_STAT;
441
442	/*
443	* Data should be driven at least 1/2 cycle before the fetch edge to make
444	* sure that data gets stable at the fetch edge.
445	*/
446	if (((spi->mode & SPI_CPOL) && (spi->mode & SPI_CPHA)) \|\|
447	(!(spi->mode & SPI_CPOL) && !(spi->mode & SPI_CPHA)))
448	regval &= ~SIRFSOC_SPI_DRV_POS_EDGE;
449	else
450	regval \|= SIRFSOC_SPI_DRV_POS_EDGE;
451
452	writel(SIRFSOC_SPI_FIFO_SC(fifo_size - 2) \|
453	SIRFSOC_SPI_FIFO_LC(fifo_size / 2) \|
454	SIRFSOC_SPI_FIFO_HC(2),
455	sspi->base + SIRFSOC_SPI_TXFIFO_LEVEL_CHK);
456	writel(SIRFSOC_SPI_FIFO_SC(2) \|
457	SIRFSOC_SPI_FIFO_LC(fifo_size / 2) \|
458	SIRFSOC_SPI_FIFO_HC(fifo_size - 2),
459	sspi->base + SIRFSOC_SPI_RXFIFO_LEVEL_CHK);
460	writel(txfifo_ctrl, sspi->base + SIRFSOC_SPI_TXFIFO_CTRL);
461	writel(rxfifo_ctrl, sspi->base + SIRFSOC_SPI_RXFIFO_CTRL);
462
463	writel(regval, sspi->base + SIRFSOC_SPI_CTRL);
464	return 0;
465	}
466
467	static int spi_sirfsoc_setup(struct spi_device *spi)
468	{
469	struct sirfsoc_spi *sspi;
470
471	if (!spi->max_speed_hz)
472	return -EINVAL;
473
474	sspi = spi_master_get_devdata(spi->master);
475
476	if (!spi->bits_per_word)
477	spi->bits_per_word = 8;
478
479	return spi_sirfsoc_setup_transfer(spi, NULL);
480	}
481
482	static int __devinit spi_sirfsoc_probe(struct platform_device *pdev)
483	{
484	struct sirfsoc_spi *sspi;
485	struct spi_master *master;
486	struct resource *mem_res;
487	int num_cs, cs_gpio, irq;
488	int i;
489	int ret;
490
491	ret = of_property_read_u32(pdev->dev.of_node,
492	"sirf,spi-num-chipselects", &num_cs);
493	if (ret < 0) {
494	dev_err(&pdev->dev, "Unable to get chip select number\n");
495	goto err_cs;
496	}
497
498	master = spi_alloc_master(&pdev->dev, sizeof(sspi) + sizeof(int) num_cs);
499	if (!master) {
500	dev_err(&pdev->dev, "Unable to allocate SPI master\n");
501	return -ENOMEM;
502	}
503	platform_set_drvdata(pdev, master);
504	sspi = spi_master_get_devdata(master);
505
506	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
507	if (!mem_res) {
508	dev_err(&pdev->dev, "Unable to get IO resource\n");
509	ret = -ENODEV;
510	goto free_master;
511	}
512	master->num_chipselect = num_cs;
513
514	for (i = 0; i < master->num_chipselect; i++) {
515	cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", i);
516	if (cs_gpio < 0) {
517	dev_err(&pdev->dev, "can't get cs gpio from DT\n");
518	ret = -ENODEV;
519	goto free_master;
520	}
521
522	sspi->chipselect[i] = cs_gpio;
523	if (cs_gpio == 0)
524	continue; /* use cs from spi controller */
525
526	ret = gpio_request(cs_gpio, DRIVER_NAME);
527	if (ret) {
528	while (i > 0) {
529	i--;
530	if (sspi->chipselect[i] > 0)
531	gpio_free(sspi->chipselect[i]);
532	}
533	dev_err(&pdev->dev, "fail to request cs gpios\n");
534	goto free_master;
535	}
536	}
537
538	sspi->base = devm_request_and_ioremap(&pdev->dev, mem_res);
539	if (!sspi->base) {
540	dev_err(&pdev->dev, "IO remap failed!\n");
541	ret = -ENOMEM;
542	goto free_master;
543	}
544
545	irq = platform_get_irq(pdev, 0);
546	if (irq < 0) {
547	ret = -ENXIO;
548	goto free_master;
549	}
550	ret = devm_request_irq(&pdev->dev, irq, spi_sirfsoc_irq, 0,
551	DRIVER_NAME, sspi);
552	if (ret)
553	goto free_master;
554
555	sspi->bitbang.master = spi_master_get(master);
556	sspi->bitbang.chipselect = spi_sirfsoc_chipselect;
557	sspi->bitbang.setup_transfer = spi_sirfsoc_setup_transfer;
558	sspi->bitbang.txrx_bufs = spi_sirfsoc_transfer;
559	sspi->bitbang.master->setup = spi_sirfsoc_setup;
560	master->bus_num = pdev->id;
561	sspi->bitbang.master->dev.of_node = pdev->dev.of_node;
562
71422f9e BS	563	sspi->p = pinctrl_get_select_default(&pdev->dev);
71422f9e BS	564	ret = IS_ERR(sspi->p);
1cc2df9d ZS	565	if (ret)
	566	goto free_master;
	567
1cc2df9d ZS	568	sspi->clk = clk_get(&pdev->dev, NULL);
	569	if (IS_ERR(sspi->clk)) {
	570	ret = -EINVAL;
71422f9e	571	goto free_pin;
1cc2df9d ZS	572	}
	573	clk_enable(sspi->clk);
	574	sspi->ctrl_freq = clk_get_rate(sspi->clk);
	575
	576	init_completion(&sspi->done);
	577
	578	tasklet_init(&sspi->tasklet_tx, spi_sirfsoc_tasklet_tx,
	579	(unsigned long)sspi);
	580
	581	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	582	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
	583	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	584	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
	585	/* We are not using dummy delay between command and data */
	586	writel(0, sspi->base + SIRFSOC_SPI_DUMMY_DELAY_CTL);
	587
	588	ret = spi_bitbang_start(&sspi->bitbang);
	589	if (ret)
	590	goto free_clk;
	591
	592	dev_info(&pdev->dev, "registerred, bus number = %d\n", master->bus_num);
	593
	594	return 0;
	595
	596	free_clk:
	597	clk_disable(sspi->clk);
	598	clk_put(sspi->clk);
71422f9e BS	599	free_pin:
71422f9e BS	600	pinctrl_put(sspi->p);
1cc2df9d ZS	601	free_master:
	602	spi_master_put(master);
	603	err_cs:
	604	return ret;
	605	}
	606
	607	static int __devexit spi_sirfsoc_remove(struct platform_device *pdev)
	608	{
	609	struct spi_master *master;
	610	struct sirfsoc_spi *sspi;
	611	int i;
	612
	613	master = platform_get_drvdata(pdev);
	614	sspi = spi_master_get_devdata(master);
	615
	616	spi_bitbang_stop(&sspi->bitbang);
	617	for (i = 0; i < master->num_chipselect; i++) {
	618	if (sspi->chipselect[i] > 0)
	619	gpio_free(sspi->chipselect[i]);
	620	}
	621	clk_disable(sspi->clk);
	622	clk_put(sspi->clk);
71422f9e	623	pinctrl_put(sspi->p);
1cc2df9d ZS	624	spi_master_put(master);
	625	return 0;
	626	}
	627
	628	#ifdef CONFIG_PM
	629	static int spi_sirfsoc_suspend(struct device *dev)
	630	{
	631	struct platform_device *pdev = to_platform_device(dev);
	632	struct spi_master *master = platform_get_drvdata(pdev);
	633	struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
	634
	635	clk_disable(sspi->clk);
	636	return 0;
	637	}
	638
	639	static int spi_sirfsoc_resume(struct device *dev)
	640	{
	641	struct platform_device *pdev = to_platform_device(dev);
	642	struct spi_master *master = platform_get_drvdata(pdev);
	643	struct sirfsoc_spi *sspi = spi_master_get_devdata(master);
	644
	645	clk_enable(sspi->clk);
	646	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	647	writel(SIRFSOC_SPI_FIFO_RESET, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
	648	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_RXFIFO_OP);
	649	writel(SIRFSOC_SPI_FIFO_START, sspi->base + SIRFSOC_SPI_TXFIFO_OP);
	650
	651	return 0;
	652	}
	653
	654	static const struct dev_pm_ops spi_sirfsoc_pm_ops = {
	655	.suspend = spi_sirfsoc_suspend,
	656	.resume = spi_sirfsoc_resume,
	657	};
	658	#endif
	659
	660	static const struct of_device_id spi_sirfsoc_of_match[] = {
	661	{ .compatible = "sirf,prima2-spi", },
	662	{}
	663	};
	664	MODULE_DEVICE_TABLE(of, sirfsoc_spi_of_match);
	665
	666	static struct platform_driver spi_sirfsoc_driver = {
	667	.driver = {
	668	.name = DRIVER_NAME,
	669	.owner = THIS_MODULE,
	670	#ifdef CONFIG_PM
	671	.pm = &spi_sirfsoc_pm_ops,
	672	#endif
	673	.of_match_table = spi_sirfsoc_of_match,
	674	},
	675	.probe = spi_sirfsoc_probe,
	676	.remove = __devexit_p(spi_sirfsoc_remove),
	677	};
	678	module_platform_driver(spi_sirfsoc_driver);
	679
	680	MODULE_DESCRIPTION("SiRF SoC SPI master driver");
	681	MODULE_AUTHOR("Zhiwu Song <[email protected]>, "
	682	"Barry Song <[email protected]>");
	683	MODULE_LICENSE("GPL v2");