Merge tag 'v4.15-rc1' into next-seccomp

Linux 4.15-rc1

1 files changed, 409 insertions, 63 deletions

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index f9698b7aeb3b..79ddefe4180d 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -53,9 +53,13 @@
 /* generic defines to abstract from the different register layouts */
 #define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
 #define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
+#define MXC_INT_RDR	BIT(4) /* Receive date threshold interrupt */
 
 /* The maximum  bytes that a sdma BD can transfer.*/
 #define MAX_SDMA_BD_BYTES  (1 << 15)
+#define MX51_ECSPI_CTRL_MAX_BURST	512
+/* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
+#define MX53_MAX_TRANSFER_BYTES		512
 
 enum spi_imx_devtype {
 	IMX1_CSPI,
@@ -63,7 +67,8 @@ enum spi_imx_devtype {
 	IMX27_CSPI,
 	IMX31_CSPI,
 	IMX35_CSPI,	/* CSPI on all i.mx except above */
-	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
+	IMX51_ECSPI,	/* ECSPI on i.mx51 */
+	IMX53_ECSPI,	/* ECSPI on i.mx53 and later */
 };
 
 struct spi_imx_data;
@@ -74,6 +79,11 @@ struct spi_imx_devtype_data {
 	void (*trigger)(struct spi_imx_data *);
 	int (*rx_available)(struct spi_imx_data *);
 	void (*reset)(struct spi_imx_data *);
+	void (*disable)(struct spi_imx_data *);
+	bool has_dmamode;
+	bool has_slavemode;
+	unsigned int fifo_size;
+	bool dynamic_burst;
 	enum spi_imx_devtype devtype;
 };
 
@@ -94,12 +104,19 @@ struct spi_imx_data {
 	unsigned int bits_per_word;
 	unsigned int spi_drctl;
 
-	unsigned int count;
+	unsigned int count, remainder;
 	void (*tx)(struct spi_imx_data *);
 	void (*rx)(struct spi_imx_data *);
 	void *rx_buf;
 	const void *tx_buf;
 	unsigned int txfifo; /* number of words pushed in tx FIFO */
+	unsigned int dynamic_burst, read_u32;
+	unsigned int word_mask;
+
+	/* Slave mode */
+	bool slave_mode;
+	bool slave_aborted;
+	unsigned int slave_burst;
 
 	/* DMA */
 	bool usedma;
@@ -125,9 +142,9 @@ static inline int is_imx51_ecspi(struct spi_imx_data *d)
 	return d->devtype_data->devtype == IMX51_ECSPI;
 }
 
-static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
+static inline int is_imx53_ecspi(struct spi_imx_data *d)
 {
-	return is_imx51_ecspi(d) ? 64 : 8;
+	return d->devtype_data->devtype == IMX53_ECSPI;
 }
 
 #define MXC_SPI_BUF_RX(type)						\
@@ -214,12 +231,15 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 	if (!master->dma_rx)
 		return false;
 
+	if (spi_imx->slave_mode)
+		return false;
+
 	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
 
 	if (bytes_per_word != 1 && bytes_per_word != 2 && bytes_per_word != 4)
 		return false;
 
-	for (i = spi_imx_get_fifosize(spi_imx) / 2; i > 0; i--) {
+	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
 		if (!(transfer->len % (i * bytes_per_word)))
 			break;
 	}
@@ -228,6 +248,7 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 		return false;
 
 	spi_imx->wml = i;
+	spi_imx->dynamic_burst = 0;
 
 	return true;
 }
@@ -242,6 +263,7 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
 #define MX51_ECSPI_CTRL_BL_OFFSET	20
+#define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
 
 #define MX51_ECSPI_CONFIG	0x0c
 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
@@ -253,6 +275,7 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 #define MX51_ECSPI_INT		0x10
 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
 #define MX51_ECSPI_INT_RREN		(1 <<  3)
+#define MX51_ECSPI_INT_RDREN		(1 <<  4)
 
 #define MX51_ECSPI_DMA      0x14
 #define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
@@ -269,6 +292,144 @@ static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
 #define MX51_ECSPI_TESTREG	0x20
 #define MX51_ECSPI_TESTREG_LBC	BIT(31)
 
+static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
+{
+	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
+#ifdef __LITTLE_ENDIAN
+	unsigned int bytes_per_word;
+#endif
+
+	if (spi_imx->rx_buf) {
+#ifdef __LITTLE_ENDIAN
+		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
+		if (bytes_per_word == 1)
+			val = cpu_to_be32(val);
+		else if (bytes_per_word == 2)
+			val = (val << 16) | (val >> 16);
+#endif
+		val &= spi_imx->word_mask;
+		*(u32 *)spi_imx->rx_buf = val;
+		spi_imx->rx_buf += sizeof(u32);
+	}
+}
+
+static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
+{
+	unsigned int bytes_per_word;
+
+	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
+	if (spi_imx->read_u32) {
+		spi_imx_buf_rx_swap_u32(spi_imx);
+		return;
+	}
+
+	if (bytes_per_word == 1)
+		spi_imx_buf_rx_u8(spi_imx);
+	else if (bytes_per_word == 2)
+		spi_imx_buf_rx_u16(spi_imx);
+}
+
+static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
+{
+	u32 val = 0;
+#ifdef __LITTLE_ENDIAN
+	unsigned int bytes_per_word;
+#endif
+
+	if (spi_imx->tx_buf) {
+		val = *(u32 *)spi_imx->tx_buf;
+		val &= spi_imx->word_mask;
+		spi_imx->tx_buf += sizeof(u32);
+	}
+
+	spi_imx->count -= sizeof(u32);
+#ifdef __LITTLE_ENDIAN
+	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
+
+	if (bytes_per_word == 1)
+		val = cpu_to_be32(val);
+	else if (bytes_per_word == 2)
+		val = (val << 16) | (val >> 16);
+#endif
+	writel(val, spi_imx->base + MXC_CSPITXDATA);
+}
+
+static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
+{
+	u32 ctrl, val;
+	unsigned int bytes_per_word;
+
+	if (spi_imx->count == spi_imx->remainder) {
+		ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
+		ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
+		if (spi_imx->count > MX51_ECSPI_CTRL_MAX_BURST) {
+			spi_imx->remainder = spi_imx->count %
+					     MX51_ECSPI_CTRL_MAX_BURST;
+			val = MX51_ECSPI_CTRL_MAX_BURST * 8 - 1;
+		} else if (spi_imx->count >= sizeof(u32)) {
+			spi_imx->remainder = spi_imx->count % sizeof(u32);
+			val = (spi_imx->count - spi_imx->remainder) * 8 - 1;
+		} else {
+			spi_imx->remainder = 0;
+			val = spi_imx->bits_per_word - 1;
+			spi_imx->read_u32 = 0;
+		}
+
+		ctrl |= (val << MX51_ECSPI_CTRL_BL_OFFSET);
+		writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
+	}
+
+	if (spi_imx->count >= sizeof(u32)) {
+		spi_imx_buf_tx_swap_u32(spi_imx);
+		return;
+	}
+
+	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
+
+	if (bytes_per_word == 1)
+		spi_imx_buf_tx_u8(spi_imx);
+	else if (bytes_per_word == 2)
+		spi_imx_buf_tx_u16(spi_imx);
+}
+
+static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
+{
+	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
+
+	if (spi_imx->rx_buf) {
+		int n_bytes = spi_imx->slave_burst % sizeof(val);
+
+		if (!n_bytes)
+			n_bytes = sizeof(val);
+
+		memcpy(spi_imx->rx_buf,
+		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
+
+		spi_imx->rx_buf += n_bytes;
+		spi_imx->slave_burst -= n_bytes;
+	}
+}
+
+static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
+{
+	u32 val = 0;
+	int n_bytes = spi_imx->count % sizeof(val);
+
+	if (!n_bytes)
+		n_bytes = sizeof(val);
+
+	if (spi_imx->tx_buf) {
+		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
+		       spi_imx->tx_buf, n_bytes);
+		val = cpu_to_be32(val);
+		spi_imx->tx_buf += n_bytes;
+	}
+
+	spi_imx->count -= n_bytes;
+
+	writel(val, spi_imx->base + MXC_CSPITXDATA);
+}
+
 /* MX51 eCSPI */
 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
 				      unsigned int fspi, unsigned int *fres)
@@ -318,6 +479,9 @@ static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
 	if (enable & MXC_INT_RR)
 		val |= MX51_ECSPI_INT_RREN;
 
+	if (enable & MXC_INT_RDR)
+		val |= MX51_ECSPI_INT_RDREN;
+
 	writel(val, spi_imx->base + MX51_ECSPI_INT);
 }
 
@@ -330,6 +494,15 @@ static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
 }
 
+static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
+{
+	u32 ctrl;
+
+	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
+	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
+	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
+}
+
 static int mx51_ecspi_config(struct spi_device *spi)
 {
 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
@@ -337,14 +510,11 @@ static int mx51_ecspi_config(struct spi_device *spi)
 	u32 clk = spi_imx->speed_hz, delay, reg;
 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
 
-	/*
-	 * The hardware seems to have a race condition when changing modes. The
-	 * current assumption is that the selection of the channel arrives
-	 * earlier in the hardware than the mode bits when they are written at
-	 * the same time.
-	 * So set master mode for all channels as we do not support slave mode.
-	 */
-	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
+	/* set Master or Slave mode */
+	if (spi_imx->slave_mode)
+		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
+	else
+		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
 
 	/*
 	 * Enable SPI_RDY handling (falling edge/level triggered).
@@ -359,9 +529,22 @@ static int mx51_ecspi_config(struct spi_device *spi)
 	/* set chip select to use */
 	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
 
-	ctrl |= (spi_imx->bits_per_word - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
+	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
+		ctrl |= (spi_imx->slave_burst * 8 - 1)
+			<< MX51_ECSPI_CTRL_BL_OFFSET;
+	else
+		ctrl |= (spi_imx->bits_per_word - 1)
+			<< MX51_ECSPI_CTRL_BL_OFFSET;
 
-	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
+	/*
+	 * eCSPI burst completion by Chip Select signal in Slave mode
+	 * is not functional for imx53 Soc, config SPI burst completed when
+	 * BURST_LENGTH + 1 bits are received
+	 */
+	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
+		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
+	else
+		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
 
 	if (spi->mode & SPI_CPHA)
 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
@@ -513,8 +696,8 @@ static int mx31_config(struct spi_device *spi)
 		reg |= MX31_CSPICTRL_POL;
 	if (spi->mode & SPI_CS_HIGH)
 		reg |= MX31_CSPICTRL_SSPOL;
-	if (spi->cs_gpio < 0)
-		reg |= (spi->cs_gpio + 32) <<
+	if (!gpio_is_valid(spi->cs_gpio))
+		reg |= (spi->chip_select) <<
 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
 						  MX31_CSPICTRL_CS_SHIFT);
 
@@ -605,8 +788,8 @@ static int mx21_config(struct spi_device *spi)
 		reg |= MX21_CSPICTRL_POL;
 	if (spi->mode & SPI_CS_HIGH)
 		reg |= MX21_CSPICTRL_SSPOL;
-	if (spi->cs_gpio < 0)
-		reg |= (spi->cs_gpio + 32) << MX21_CSPICTRL_CS_SHIFT;
+	if (!gpio_is_valid(spi->cs_gpio))
+		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
 
 	writel(reg, spi_imx->base + MXC_CSPICTRL);
 
@@ -693,6 +876,10 @@ static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
 	.trigger = mx1_trigger,
 	.rx_available = mx1_rx_available,
 	.reset = mx1_reset,
+	.fifo_size = 8,
+	.has_dmamode = false,
+	.dynamic_burst = false,
+	.has_slavemode = false,
 	.devtype = IMX1_CSPI,
 };
 
@@ -702,6 +889,10 @@ static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
 	.trigger = mx21_trigger,
 	.rx_available = mx21_rx_available,
 	.reset = mx21_reset,
+	.fifo_size = 8,
+	.has_dmamode = false,
+	.dynamic_burst = false,
+	.has_slavemode = false,
 	.devtype = IMX21_CSPI,
 };
 
@@ -712,6 +903,10 @@ static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
 	.trigger = mx21_trigger,
 	.rx_available = mx21_rx_available,
 	.reset = mx21_reset,
+	.fifo_size = 8,
+	.has_dmamode = false,
+	.dynamic_burst = false,
+	.has_slavemode = false,
 	.devtype = IMX27_CSPI,
 };
 
@@ -721,6 +916,10 @@ static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
 	.trigger = mx31_trigger,
 	.rx_available = mx31_rx_available,
 	.reset = mx31_reset,
+	.fifo_size = 8,
+	.has_dmamode = false,
+	.dynamic_burst = false,
+	.has_slavemode = false,
 	.devtype = IMX31_CSPI,
 };
 
@@ -731,6 +930,10 @@ static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
 	.trigger = mx31_trigger,
 	.rx_available = mx31_rx_available,
 	.reset = mx31_reset,
+	.fifo_size = 8,
+	.has_dmamode = true,
+	.dynamic_burst = false,
+	.has_slavemode = false,
 	.devtype = IMX35_CSPI,
 };
 
@@ -740,9 +943,27 @@ static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
 	.trigger = mx51_ecspi_trigger,
 	.rx_available = mx51_ecspi_rx_available,
 	.reset = mx51_ecspi_reset,
+	.fifo_size = 64,
+	.has_dmamode = true,
+	.dynamic_burst = true,
+	.has_slavemode = true,
+	.disable = mx51_ecspi_disable,
 	.devtype = IMX51_ECSPI,
 };
 
+static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
+	.intctrl = mx51_ecspi_intctrl,
+	.config = mx51_ecspi_config,
+	.trigger = mx51_ecspi_trigger,
+	.rx_available = mx51_ecspi_rx_available,
+	.reset = mx51_ecspi_reset,
+	.fifo_size = 64,
+	.has_dmamode = true,
+	.has_slavemode = true,
+	.disable = mx51_ecspi_disable,
+	.devtype = IMX53_ECSPI,
+};
+
 static const struct platform_device_id spi_imx_devtype[] = {
 	{
 		.name = "imx1-cspi",
@@ -763,6 +984,9 @@ static const struct platform_device_id spi_imx_devtype[] = {
 		.name = "imx51-ecspi",
 		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
 	}, {
+		.name = "imx53-ecspi",
+		.driver_data = (kernel_ulong_t) &imx53_ecspi_devtype_data,
+	}, {
 		/* sentinel */
 	}
 };
@@ -774,6 +998,7 @@ static const struct of_device_id spi_imx_dt_ids[] = {
 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
+	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
@@ -783,6 +1008,9 @@ static void spi_imx_chipselect(struct spi_device *spi, int is_active)
 	int active = is_active != BITBANG_CS_INACTIVE;
 	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
 
+	if (spi->mode & SPI_NO_CS)
+		return;
+
 	if (!gpio_is_valid(spi->cs_gpio))
 		return;
 
@@ -791,21 +1019,25 @@ static void spi_imx_chipselect(struct spi_device *spi, int is_active)
 
 static void spi_imx_push(struct spi_imx_data *spi_imx)
 {
-	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
+	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
 		if (!spi_imx->count)
 			break;
+		if (spi_imx->txfifo && (spi_imx->count == spi_imx->remainder))
+			break;
 		spi_imx->tx(spi_imx);
 		spi_imx->txfifo++;
 	}
 
-	spi_imx->devtype_data->trigger(spi_imx);
+	if (!spi_imx->slave_mode)
+		spi_imx->devtype_data->trigger(spi_imx);
 }
 
 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
 {
 	struct spi_imx_data *spi_imx = dev_id;
 
-	while (spi_imx->devtype_data->rx_available(spi_imx)) {
+	while (spi_imx->txfifo &&
+	       spi_imx->devtype_data->rx_available(spi_imx)) {
 		spi_imx->rx(spi_imx);
 		spi_imx->txfifo--;
 	}
@@ -887,15 +1119,37 @@ static int spi_imx_setupxfer(struct spi_device *spi,
 	spi_imx->speed_hz  = t->speed_hz;
 
 	/* Initialize the functions for transfer */
-	if (spi_imx->bits_per_word <= 8) {
-		spi_imx->rx = spi_imx_buf_rx_u8;
-		spi_imx->tx = spi_imx_buf_tx_u8;
-	} else if (spi_imx->bits_per_word <= 16) {
-		spi_imx->rx = spi_imx_buf_rx_u16;
-		spi_imx->tx = spi_imx_buf_tx_u16;
+	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode) {
+		u32 mask;
+
+		spi_imx->dynamic_burst = 0;
+		spi_imx->remainder = 0;
+		spi_imx->read_u32  = 1;
+
+		mask = (1 << spi_imx->bits_per_word) - 1;
+		spi_imx->rx = spi_imx_buf_rx_swap;
+		spi_imx->tx = spi_imx_buf_tx_swap;
+		spi_imx->dynamic_burst = 1;
+		spi_imx->remainder = t->len;
+
+		if (spi_imx->bits_per_word <= 8)
+			spi_imx->word_mask = mask << 24 | mask << 16
+					     | mask << 8 | mask;
+		else if (spi_imx->bits_per_word <= 16)
+			spi_imx->word_mask = mask << 16 | mask;
+		else
+			spi_imx->word_mask = mask;
 	} else {
-		spi_imx->rx = spi_imx_buf_rx_u32;
-		spi_imx->tx = spi_imx_buf_tx_u32;
+		if (spi_imx->bits_per_word <= 8) {
+			spi_imx->rx = spi_imx_buf_rx_u8;
+			spi_imx->tx = spi_imx_buf_tx_u8;
+		} else if (spi_imx->bits_per_word <= 16) {
+			spi_imx->rx = spi_imx_buf_rx_u16;
+			spi_imx->tx = spi_imx_buf_tx_u16;
+		} else {
+			spi_imx->rx = spi_imx_buf_rx_u32;
+			spi_imx->tx = spi_imx_buf_tx_u32;
+		}
 	}
 
 	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
@@ -909,6 +1163,12 @@ static int spi_imx_setupxfer(struct spi_device *spi,
 			return ret;
 	}
 
+	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
+		spi_imx->rx = mx53_ecspi_rx_slave;
+		spi_imx->tx = mx53_ecspi_tx_slave;
+		spi_imx->slave_burst = t->len;
+	}
+
 	spi_imx->devtype_data->config(spi);
 
 	return 0;
@@ -938,7 +1198,7 @@ static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
 	if (of_machine_is_compatible("fsl,imx6dl"))
 		return 0;
 
-	spi_imx->wml = spi_imx_get_fifosize(spi_imx) / 2;
+	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
 
 	/* Prepare for TX DMA: */
 	master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
@@ -1093,11 +1353,61 @@ static int spi_imx_pio_transfer(struct spi_device *spi,
 	return transfer->len;
 }
 
+static int spi_imx_pio_transfer_slave(struct spi_device *spi,
+				      struct spi_transfer *transfer)
+{
+	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
+	int ret = transfer->len;
+
+	if (is_imx53_ecspi(spi_imx) &&
+	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
+		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
+			MX53_MAX_TRANSFER_BYTES);
+		return -EMSGSIZE;
+	}
+
+	spi_imx->tx_buf = transfer->tx_buf;
+	spi_imx->rx_buf = transfer->rx_buf;
+	spi_imx->count = transfer->len;
+	spi_imx->txfifo = 0;
+
+	reinit_completion(&spi_imx->xfer_done);
+	spi_imx->slave_aborted = false;
+
+	spi_imx_push(spi_imx);
+
+	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
+
+	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
+	    spi_imx->slave_aborted) {
+		dev_dbg(&spi->dev, "interrupted\n");
+		ret = -EINTR;
+	}
+
+	/* ecspi has a HW issue when works in Slave mode,
+	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
+	 * ECSPI_TXDATA keeps shift out the last word data,
+	 * so we have to disable ECSPI when in slave mode after the
+	 * transfer completes
+	 */
+	if (spi_imx->devtype_data->disable)
+		spi_imx->devtype_data->disable(spi_imx);
+
+	return ret;
+}
+
 static int spi_imx_transfer(struct spi_device *spi,
 				struct spi_transfer *transfer)
 {
 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
 
+	/* flush rxfifo before transfer */
+	while (spi_imx->devtype_data->rx_available(spi_imx))
+		spi_imx->rx(spi_imx);
+
+	if (spi_imx->slave_mode)
+		return spi_imx_pio_transfer_slave(spi, transfer);
+
 	if (spi_imx->usedma)
 		return spi_imx_dma_transfer(spi_imx, transfer);
 	else
@@ -1109,6 +1419,9 @@ static int spi_imx_setup(struct spi_device *spi)
 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
 
+	if (spi->mode & SPI_NO_CS)
+		return 0;
+
 	if (gpio_is_valid(spi->cs_gpio))
 		gpio_direction_output(spi->cs_gpio,
 				      spi->mode & SPI_CS_HIGH ? 0 : 1);
@@ -1151,6 +1464,16 @@ spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
 	return 0;
 }
 
+static int spi_imx_slave_abort(struct spi_master *master)
+{
+	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
+
+	spi_imx->slave_aborted = true;
+	complete(&spi_imx->xfer_done);
+
+	return 0;
+}
+
 static int spi_imx_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
@@ -1162,13 +1485,23 @@ static int spi_imx_probe(struct platform_device *pdev)
 	struct spi_imx_data *spi_imx;
 	struct resource *res;
 	int i, ret, irq, spi_drctl;
+	const struct spi_imx_devtype_data *devtype_data = of_id ? of_id->data :
+		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
+	bool slave_mode;
 
 	if (!np && !mxc_platform_info) {
 		dev_err(&pdev->dev, "can't get the platform data\n");
 		return -EINVAL;
 	}
 
-	master = spi_alloc_master(&pdev->dev, sizeof(struct spi_imx_data));
+	slave_mode = devtype_data->has_slavemode &&
+			of_property_read_bool(np, "spi-slave");
+	if (slave_mode)
+		master = spi_alloc_slave(&pdev->dev,
+					 sizeof(struct spi_imx_data));
+	else
+		master = spi_alloc_master(&pdev->dev,
+					  sizeof(struct spi_imx_data));
 	if (!master)
 		return -ENOMEM;
 
@@ -1186,20 +1519,29 @@ static int spi_imx_probe(struct platform_device *pdev)
 	spi_imx = spi_master_get_devdata(master);
 	spi_imx->bitbang.master = master;
 	spi_imx->dev = &pdev->dev;
+	spi_imx->slave_mode = slave_mode;
 
-	spi_imx->devtype_data = of_id ? of_id->data :
-		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
+	spi_imx->devtype_data = devtype_data;
 
+	/* Get number of chip selects, either platform data or OF */
 	if (mxc_platform_info) {
 		master->num_chipselect = mxc_platform_info->num_chipselect;
-		master->cs_gpios = devm_kzalloc(&master->dev,
-			sizeof(int) * master->num_chipselect, GFP_KERNEL);
-		if (!master->cs_gpios)
-			return -ENOMEM;
+		if (mxc_platform_info->chipselect) {
+			master->cs_gpios = devm_kzalloc(&master->dev,
+				sizeof(int) * master->num_chipselect, GFP_KERNEL);
+			if (!master->cs_gpios)
+				return -ENOMEM;
+
+			for (i = 0; i < master->num_chipselect; i++)
+				master->cs_gpios[i] = mxc_platform_info->chipselect[i];
+		}
+	} else {
+		u32 num_cs;
 
-		for (i = 0; i < master->num_chipselect; i++)
-			master->cs_gpios[i] = mxc_platform_info->chipselect[i];
- 	}
+		if (!of_property_read_u32(np, "num-cs", &num_cs))
+			master->num_chipselect = num_cs;
+		/* If not preset, default value of 1 is used */
+	}
 
 	spi_imx->bitbang.chipselect = spi_imx_chipselect;
 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
@@ -1208,8 +1550,11 @@ static int spi_imx_probe(struct platform_device *pdev)
 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
-	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
-	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx))
+	spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
+	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
+					     | SPI_NO_CS;
+	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
+	    is_imx53_ecspi(spi_imx))
 		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
 
 	spi_imx->spi_drctl = spi_drctl;
@@ -1262,7 +1607,7 @@ static int spi_imx_probe(struct platform_device *pdev)
 	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
 	 * if validated on other chips.
 	 */
-	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx)) {
+	if (spi_imx->devtype_data->has_dmamode) {
 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
 		if (ret == -EPROBE_DEFER)
 			goto out_clk_put;
@@ -1277,37 +1622,38 @@ static int spi_imx_probe(struct platform_device *pdev)
 	spi_imx->devtype_data->intctrl(spi_imx, 0);
 
 	master->dev.of_node = pdev->dev.of_node;
+
+	/* Request GPIO CS lines, if any */
+	if (!spi_imx->slave_mode && master->cs_gpios) {
+		for (i = 0; i < master->num_chipselect; i++) {
+			if (!gpio_is_valid(master->cs_gpios[i]))
+				continue;
+
+			ret = devm_gpio_request(&pdev->dev,
+						master->cs_gpios[i],
+						DRIVER_NAME);
+			if (ret) {
+				dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
+					master->cs_gpios[i]);
+				goto out_spi_bitbang;
+			}
+		}
+	}
+
 	ret = spi_bitbang_start(&spi_imx->bitbang);
 	if (ret) {
 		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
 		goto out_clk_put;
 	}
 
-	if (!master->cs_gpios) {
-		dev_err(&pdev->dev, "No CS GPIOs available\n");
-		ret = -EINVAL;
-		goto out_clk_put;
-	}
-
-	for (i = 0; i < master->num_chipselect; i++) {
-		if (!gpio_is_valid(master->cs_gpios[i]))
-			continue;
-
-		ret = devm_gpio_request(&pdev->dev, master->cs_gpios[i],
-					DRIVER_NAME);
-		if (ret) {
-			dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
-				master->cs_gpios[i]);
-			goto out_clk_put;
-		}
-	}
-
 	dev_info(&pdev->dev, "probed\n");
 
 	clk_disable(spi_imx->clk_ipg);
 	clk_disable(spi_imx->clk_per);
 	return ret;
 
+out_spi_bitbang:
+	spi_bitbang_stop(&spi_imx->bitbang);
 out_clk_put:
 	clk_disable_unprepare(spi_imx->clk_ipg);
 out_put_per: