diff options
Diffstat (limited to 'drivers/spi/spi-sirf.c')
| -rw-r--r-- | drivers/spi/spi-sirf.c | 852 | 
1 files changed, 852 insertions, 0 deletions
diff --git a/drivers/spi/spi-sirf.c b/drivers/spi/spi-sirf.c new file mode 100644 index 00000000000..95ac276eaaf --- /dev/null +++ b/drivers/spi/spi-sirf.c @@ -0,0 +1,852 @@ +/* + * 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/completion.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/dmaengine.h> +#include <linux/dma-direction.h> +#include <linux/dma-mapping.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_IO_DMA		BIT(4) +#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) + +/* + * only if the rx/tx buffer and transfer size are 4-bytes aligned, we use dma + * due to the limitation of dma controller + */ + +#define ALIGNED(x) (!((u32)x & 0x3)) +#define IS_DMA_VALID(x) (x && ALIGNED(x->tx_buf) && ALIGNED(x->rx_buf) && \ +	ALIGNED(x->len) && (x->len < 2 * PAGE_SIZE)) + +#define SIRFSOC_MAX_CMD_BYTES	4 + +struct sirfsoc_spi { +	struct spi_bitbang bitbang; +	struct completion rx_done; +	struct completion tx_done; + +	void __iomem *base; +	u32 ctrl_freq;  /* SPI controller clock speed */ +	struct clk *clk; + +	/* 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_word; +	unsigned int left_rx_word; + +	/* rx & tx DMA channels */ +	struct dma_chan *rx_chan; +	struct dma_chan *tx_chan; +	dma_addr_t src_start; +	dma_addr_t dst_start; +	void *dummypage; +	int word_width; /* in bytes */ + +	/* +	 * if tx size is not more than 4 and rx size is NULL, use +	 * command model +	 */ +	bool	tx_by_cmd; + +	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_word--; +} + +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_word--; +} + +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_word--; +} + +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_word--; +} + +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_word--; + +} + +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_word--; +} + +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); +	if (sspi->tx_by_cmd && (spi_stat & SIRFSOC_SPI_FRM_END)) { +		complete(&sspi->tx_done); +		writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN); +		writel(SIRFSOC_SPI_INT_MASK_ALL, +				sspi->base + SIRFSOC_SPI_INT_STATUS); +		return IRQ_HANDLED; +	} + +	/* Error Conditions */ +	if (spi_stat & SIRFSOC_SPI_RX_OFLOW || +			spi_stat & SIRFSOC_SPI_TX_UFLOW) { +		complete(&sspi->tx_done); +		complete(&sspi->rx_done); +		writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN); +		writel(SIRFSOC_SPI_INT_MASK_ALL, +				sspi->base + SIRFSOC_SPI_INT_STATUS); +		return IRQ_HANDLED; +	} +	if (spi_stat & SIRFSOC_SPI_TXFIFO_EMPTY) +		complete(&sspi->tx_done); +	while (!(readl(sspi->base + SIRFSOC_SPI_INT_STATUS) & +		SIRFSOC_SPI_RX_IO_DMA)) +		cpu_relax(); +	complete(&sspi->rx_done); +	writel(0x0, sspi->base + SIRFSOC_SPI_INT_EN); +	writel(SIRFSOC_SPI_INT_MASK_ALL, +			sspi->base + SIRFSOC_SPI_INT_STATUS); + +	return IRQ_HANDLED; +} + +static void spi_sirfsoc_dma_fini_callback(void *data) +{ +	struct completion *dma_complete = data; + +	complete(dma_complete); +} + +static int spi_sirfsoc_cmd_transfer(struct spi_device *spi, +	struct spi_transfer *t) +{ +	struct sirfsoc_spi *sspi; +	int timeout = t->len * 10; +	u32 cmd; + +	sspi = spi_master_get_devdata(spi->master); +	memcpy(&cmd, sspi->tx, t->len); +	if (sspi->word_width == 1 && !(spi->mode & SPI_LSB_FIRST)) +		cmd = cpu_to_be32(cmd) >> +			((SIRFSOC_MAX_CMD_BYTES - t->len) * 8); +	if (sspi->word_width == 2 && t->len == 4 && +			(!(spi->mode & SPI_LSB_FIRST))) +		cmd = ((cmd & 0xffff) << 16) | (cmd >> 16); +	writel(cmd, sspi->base + SIRFSOC_SPI_CMD); +	writel(SIRFSOC_SPI_FRM_END_INT_EN, +		sspi->base + SIRFSOC_SPI_INT_EN); +	writel(SIRFSOC_SPI_CMD_TX_EN, +		sspi->base + SIRFSOC_SPI_TX_RX_EN); +	if (wait_for_completion_timeout(&sspi->tx_done, timeout) == 0) { +		dev_err(&spi->dev, "cmd transfer timeout\n"); +		return 0; +	} + +	return t->len; +} + +static void spi_sirfsoc_dma_transfer(struct spi_device *spi, +	struct spi_transfer *t) +{ +	struct sirfsoc_spi *sspi; +	struct dma_async_tx_descriptor *rx_desc, *tx_desc; +	int timeout = t->len * 10; + +	sspi = spi_master_get_devdata(spi->master); +	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); +	writel(0, sspi->base + SIRFSOC_SPI_INT_EN); +	writel(SIRFSOC_SPI_INT_MASK_ALL, sspi->base + SIRFSOC_SPI_INT_STATUS); +	if (sspi->left_tx_word < SIRFSOC_SPI_DAT_FRM_LEN_MAX) { +		writel(readl(sspi->base + SIRFSOC_SPI_CTRL) | +			SIRFSOC_SPI_ENA_AUTO_CLR | SIRFSOC_SPI_MUL_DAT_MODE, +			sspi->base + SIRFSOC_SPI_CTRL); +		writel(sspi->left_tx_word - 1, +				sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN); +		writel(sspi->left_tx_word - 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); +	} +	sspi->dst_start = dma_map_single(&spi->dev, sspi->rx, t->len, +					(t->tx_buf != t->rx_buf) ? +					DMA_FROM_DEVICE : DMA_BIDIRECTIONAL); +	rx_desc = dmaengine_prep_slave_single(sspi->rx_chan, +		sspi->dst_start, t->len, DMA_DEV_TO_MEM, +		DMA_PREP_INTERRUPT | DMA_CTRL_ACK); +	rx_desc->callback = spi_sirfsoc_dma_fini_callback; +	rx_desc->callback_param = &sspi->rx_done; + +	sspi->src_start = dma_map_single(&spi->dev, (void *)sspi->tx, t->len, +					(t->tx_buf != t->rx_buf) ? +					DMA_TO_DEVICE : DMA_BIDIRECTIONAL); +	tx_desc = dmaengine_prep_slave_single(sspi->tx_chan, +		sspi->src_start, t->len, DMA_MEM_TO_DEV, +		DMA_PREP_INTERRUPT | DMA_CTRL_ACK); +	tx_desc->callback = spi_sirfsoc_dma_fini_callback; +	tx_desc->callback_param = &sspi->tx_done; + +	dmaengine_submit(tx_desc); +	dmaengine_submit(rx_desc); +	dma_async_issue_pending(sspi->tx_chan); +	dma_async_issue_pending(sspi->rx_chan); +	writel(SIRFSOC_SPI_RX_EN | SIRFSOC_SPI_TX_EN, +			sspi->base + SIRFSOC_SPI_TX_RX_EN); +	if (wait_for_completion_timeout(&sspi->rx_done, timeout) == 0) { +		dev_err(&spi->dev, "transfer timeout\n"); +		dmaengine_terminate_all(sspi->rx_chan); +	} else +		sspi->left_rx_word = 0; +	/* +	 * we only wait tx-done event if transferring by DMA. for PIO, +	 * we get rx data by writing tx data, so if rx is done, tx has +	 * done earlier +	 */ +	if (wait_for_completion_timeout(&sspi->tx_done, timeout) == 0) { +		dev_err(&spi->dev, "transfer timeout\n"); +		dmaengine_terminate_all(sspi->tx_chan); +	} +	dma_unmap_single(&spi->dev, sspi->src_start, t->len, DMA_TO_DEVICE); +	dma_unmap_single(&spi->dev, sspi->dst_start, t->len, DMA_FROM_DEVICE); +	/* TX, RX FIFO stop */ +	writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP); +	writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP); +	if (sspi->left_tx_word >= SIRFSOC_SPI_DAT_FRM_LEN_MAX) +		writel(0, sspi->base + SIRFSOC_SPI_TX_RX_EN); +} + +static void spi_sirfsoc_pio_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); +	do { +		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); +		writel(0, sspi->base + SIRFSOC_SPI_INT_EN); +		writel(SIRFSOC_SPI_INT_MASK_ALL, +			sspi->base + SIRFSOC_SPI_INT_STATUS); +		writel(readl(sspi->base + SIRFSOC_SPI_CTRL) | +			SIRFSOC_SPI_MUL_DAT_MODE | SIRFSOC_SPI_ENA_AUTO_CLR, +			sspi->base + SIRFSOC_SPI_CTRL); +		writel(min(sspi->left_tx_word, (u32)(256 / sspi->word_width)) +				- 1, sspi->base + SIRFSOC_SPI_TX_DMA_IO_LEN); +		writel(min(sspi->left_rx_word, (u32)(256 / sspi->word_width)) +				- 1, sspi->base + SIRFSOC_SPI_RX_DMA_IO_LEN); +		while (!((readl(sspi->base + SIRFSOC_SPI_TXFIFO_STATUS) +			& SIRFSOC_SPI_FIFO_FULL)) && sspi->left_tx_word) +			sspi->tx_word(sspi); +		writel(SIRFSOC_SPI_TXFIFO_EMPTY_INT_EN | +			SIRFSOC_SPI_TX_UFLOW_INT_EN | +			SIRFSOC_SPI_RX_OFLOW_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->tx_done, timeout) || +			!wait_for_completion_timeout(&sspi->rx_done, timeout)) { +			dev_err(&spi->dev, "transfer timeout\n"); +			break; +		} +		while (!((readl(sspi->base + SIRFSOC_SPI_RXFIFO_STATUS) +			& SIRFSOC_SPI_FIFO_EMPTY)) && sspi->left_rx_word) +			sspi->rx_word(sspi); +		writel(0, sspi->base + SIRFSOC_SPI_RXFIFO_OP); +		writel(0, sspi->base + SIRFSOC_SPI_TXFIFO_OP); +	} while (sspi->left_tx_word != 0 || sspi->left_rx_word != 0); +} + +static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t) +{ +	struct sirfsoc_spi *sspi; +	sspi = spi_master_get_devdata(spi->master); + +	sspi->tx = t->tx_buf ? t->tx_buf : sspi->dummypage; +	sspi->rx = t->rx_buf ? t->rx_buf : sspi->dummypage; +	sspi->left_tx_word = sspi->left_rx_word = t->len / sspi->word_width; +	reinit_completion(&sspi->rx_done); +	reinit_completion(&sspi->tx_done); +	/* +	 * in the transfer, if transfer data using command register with rx_buf +	 * null, just fill command data into command register and wait for its +	 * completion. +	 */ +	if (sspi->tx_by_cmd) +		spi_sirfsoc_cmd_transfer(spi, t); +	else if (IS_DMA_VALID(t)) +		spi_sirfsoc_dma_transfer(spi, t); +	else +		spi_sirfsoc_pio_transfer(spi, t); + +	return t->len - sspi->left_rx_word * sspi->word_width; +} + +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); +		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]; +		switch (value) { +		case BITBANG_CS_ACTIVE: +			gpio_direction_output(gpio, +					spi->mode & SPI_CS_HIGH ? 1 : 0); +			break; +		case BITBANG_CS_INACTIVE: +			gpio_direction_output(gpio, +					spi->mode & SPI_CS_HIGH ? 0 : 1); +			break; +		} +	} +} + +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 : spi->bits_per_word; +	hz = t && t->speed_hz ? t->speed_hz : spi->max_speed_hz; + +	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; +		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; +		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; +		break; +	default: +		BUG(); +	} + +	sspi->word_width = DIV_ROUND_UP(bits_per_word, 8); +	txfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) | +					   sspi->word_width; +	rxfifo_ctrl = SIRFSOC_SPI_FIFO_THD(SIRFSOC_SPI_FIFO_SIZE / 2) | +					   sspi->word_width; + +	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); + +	if (t && t->tx_buf && !t->rx_buf && (t->len <= SIRFSOC_MAX_CMD_BYTES)) { +		regval |= (SIRFSOC_SPI_CMD_BYTE_NUM((t->len - 1)) | +				SIRFSOC_SPI_CMD_MODE); +		sspi->tx_by_cmd = true; +	} else { +		regval &= ~SIRFSOC_SPI_CMD_MODE; +		sspi->tx_by_cmd = false; +	} +	/* +	 * set spi controller in RISC chipselect mode, we are controlling CS by +	 * software BITBANG_CS_ACTIVE and BITBANG_CS_INACTIVE. +	 */ +	regval |= SIRFSOC_SPI_CS_IO_MODE; +	writel(regval, sspi->base + SIRFSOC_SPI_CTRL); + +	if (IS_DMA_VALID(t)) { +		/* Enable DMA mode for RX, TX */ +		writel(0, sspi->base + SIRFSOC_SPI_TX_DMA_IO_CTRL); +		writel(SIRFSOC_SPI_RX_DMA_FLUSH, +			sspi->base + SIRFSOC_SPI_RX_DMA_IO_CTRL); +	} else { +		/* 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); +	} + +	return 0; +} + +static int spi_sirfsoc_setup(struct spi_device *spi) +{ +	if (!spi->max_speed_hz) +		return -EINVAL; + +	return spi_sirfsoc_setup_transfer(spi, NULL); +} + +static int 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); + +	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; +		} +	} + +	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0); +	sspi->base = devm_ioremap_resource(&pdev->dev, mem_res); +	if (IS_ERR(sspi->base)) { +		ret = PTR_ERR(sspi->base); +		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 = 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; +	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_CS_HIGH; +	master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(12) | +					SPI_BPW_MASK(16) | SPI_BPW_MASK(32); +	sspi->bitbang.master->dev.of_node = pdev->dev.of_node; + +	/* request DMA channels */ +	sspi->rx_chan = dma_request_slave_channel(&pdev->dev, "rx"); +	if (!sspi->rx_chan) { +		dev_err(&pdev->dev, "can not allocate rx dma channel\n"); +		ret = -ENODEV; +		goto free_master; +	} +	sspi->tx_chan = dma_request_slave_channel(&pdev->dev, "tx"); +	if (!sspi->tx_chan) { +		dev_err(&pdev->dev, "can not allocate tx dma channel\n"); +		ret = -ENODEV; +		goto free_rx_dma; +	} + +	sspi->clk = clk_get(&pdev->dev, NULL); +	if (IS_ERR(sspi->clk)) { +		ret = PTR_ERR(sspi->clk); +		goto free_tx_dma; +	} +	clk_prepare_enable(sspi->clk); +	sspi->ctrl_freq = clk_get_rate(sspi->clk); + +	init_completion(&sspi->rx_done); +	init_completion(&sspi->tx_done); + +	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); + +	sspi->dummypage = kmalloc(2 * PAGE_SIZE, GFP_KERNEL); +	if (!sspi->dummypage) { +		ret = -ENOMEM; +		goto free_clk; +	} + +	ret = spi_bitbang_start(&sspi->bitbang); +	if (ret) +		goto free_dummypage; + +	dev_info(&pdev->dev, "registerred, bus number = %d\n", master->bus_num); + +	return 0; +free_dummypage: +	kfree(sspi->dummypage); +free_clk: +	clk_disable_unprepare(sspi->clk); +	clk_put(sspi->clk); +free_tx_dma: +	dma_release_channel(sspi->tx_chan); +free_rx_dma: +	dma_release_channel(sspi->rx_chan); +free_master: +	spi_master_put(master); +err_cs: +	return ret; +} + +static int  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]); +	} +	kfree(sspi->dummypage); +	clk_disable_unprepare(sspi->clk); +	clk_put(sspi->clk); +	dma_release_channel(sspi->rx_chan); +	dma_release_channel(sspi->tx_chan); +	spi_master_put(master); +	return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int spi_sirfsoc_suspend(struct device *dev) +{ +	struct spi_master *master = dev_get_drvdata(dev); +	struct sirfsoc_spi *sspi = spi_master_get_devdata(master); +	int ret; + +	ret = spi_master_suspend(master); +	if (ret) +		return ret; + +	clk_disable(sspi->clk); +	return 0; +} + +static int spi_sirfsoc_resume(struct device *dev) +{ +	struct spi_master *master = dev_get_drvdata(dev); +	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 spi_master_resume(master); +} +#endif + +static SIMPLE_DEV_PM_OPS(spi_sirfsoc_pm_ops, spi_sirfsoc_suspend, +			 spi_sirfsoc_resume); + +static const struct of_device_id spi_sirfsoc_of_match[] = { +	{ .compatible = "sirf,prima2-spi", }, +	{ .compatible = "sirf,marco-spi", }, +	{} +}; +MODULE_DEVICE_TABLE(of, spi_sirfsoc_of_match); + +static struct platform_driver spi_sirfsoc_driver = { +	.driver = { +		.name = DRIVER_NAME, +		.owner = THIS_MODULE, +		.pm     = &spi_sirfsoc_pm_ops, +		.of_match_table = spi_sirfsoc_of_match, +	}, +	.probe = spi_sirfsoc_probe, +	.remove = spi_sirfsoc_remove, +}; +module_platform_driver(spi_sirfsoc_driver); +MODULE_DESCRIPTION("SiRF SoC SPI master driver"); +MODULE_AUTHOR("Zhiwu Song <Zhiwu.Song@csr.com>"); +MODULE_AUTHOR("Barry Song <Baohua.Song@csr.com>"); +MODULE_LICENSE("GPL v2");  | 
