Merge remote-tracking branch 'spi/for-next'

16 files changed, 342 insertions, 56 deletions

diff --git a/Documentation/devicetree/bindings/powerpc/fsl/mpc5121-psc.txt b/Documentation/devicetree/bindings/powerpc/fsl/mpc5121-psc.txt
index 8832e8798912..647817527c88 100644
--- a/Documentation/devicetree/bindings/powerpc/fsl/mpc5121-psc.txt
+++ b/Documentation/devicetree/bindings/powerpc/fsl/mpc5121-psc.txt
@@ -6,14 +6,14 @@ PSC in UART mode
 For PSC in UART mode the needed PSC serial devices
 are specified by fsl,mpc5121-psc-uart nodes in the
 fsl,mpc5121-immr SoC node. Additionally the PSC FIFO
-Controller node fsl,mpc5121-psc-fifo is requered there:
+Controller node fsl,mpc5121-psc-fifo is required there:
 
-fsl,mpc5121-psc-uart nodes
+fsl,mpc512x-psc-uart nodes
 --------------------------
 
 Required properties :
- - compatible : Should contain "fsl,mpc5121-psc-uart" and "fsl,mpc5121-psc"
- - cell-index : Index of the PSC in hardware
+ - compatible : Should contain "fsl,<soc>-psc-uart" and "fsl,<soc>-psc"
+   Supported <soc>s: mpc5121, mpc5125
  - reg : Offset and length of the register set for the PSC device
  - interrupts : <a b> where a is the interrupt number of the
    PSC FIFO Controller and b is a field that represents an
@@ -25,12 +25,21 @@ Recommended properties :
  - fsl,rx-fifo-size : the size of the RX fifo slice (a multiple of 4)
  - fsl,tx-fifo-size : the size of the TX fifo slice (a multiple of 4)
 
+PSC in SPI mode
+---------------
 
-fsl,mpc5121-psc-fifo node
+Similar to the UART mode a PSC can be operated in SPI mode. The compatible used
+for that is fsl,mpc5121-psc-spi. It requires a fsl,mpc5121-psc-fifo as well.
+The required and recommended properties are identical to the
+fsl,mpc5121-psc-uart nodes, just use spi instead of uart in the compatible
+string.
+
+fsl,mpc512x-psc-fifo node
 -------------------------
 
 Required properties :
- - compatible : Should be "fsl,mpc5121-psc-fifo"
+ - compatible : Should be "fsl,<soc>-psc-fifo"
+   Supported <soc>s: mpc5121, mpc5125
  - reg : Offset and length of the register set for the PSC
          FIFO Controller
  - interrupts : <a b> where a is the interrupt number of the
@@ -39,6 +48,9 @@ Required properties :
  - interrupt-parent : the phandle for the interrupt controller that
    services interrupts for this device.
 
+Recommended properties :
+ - clocks : specifies the clock needed to operate the fifo controller
+ - clock-names : name(s) for the clock(s) listed in clocks
 
 Example for a board using PSC0 and PSC1 devices in serial mode:
 
diff --git a/Documentation/devicetree/bindings/spi/spi-img-spfi.txt b/Documentation/devicetree/bindings/spi/spi-img-spfi.txt
index e02fbf18c82c..494db6012d02 100644
--- a/Documentation/devicetree/bindings/spi/spi-img-spfi.txt
+++ b/Documentation/devicetree/bindings/spi/spi-img-spfi.txt
@@ -21,6 +21,7 @@ Required properties:
 Optional properties:
 - img,supports-quad-mode: Should be set if the interface supports quad mode
   SPI transfers.
+- spfi-max-frequency: Maximum speed supported by the spfi block.
 
 Example:
 
diff --git a/arch/powerpc/include/asm/mpc52xx_psc.h b/arch/powerpc/include/asm/mpc52xx_psc.h
index d0ece257d310..04c7e8fc24c2 100644
--- a/arch/powerpc/include/asm/mpc52xx_psc.h
+++ b/arch/powerpc/include/asm/mpc52xx_psc.h
@@ -150,7 +150,10 @@
 
 /* Structure of the hardware registers */
 struct mpc52xx_psc {
-	u8		mode;		/* PSC + 0x00 */
+	union {
+		u8	mode;		/* PSC + 0x00 */
+		u8	mr2;
+	};
 	u8		reserved0[3];
 	union {				/* PSC + 0x04 */
 		u16	status;
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 0cae1694014d..b0f30fb68914 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -612,7 +612,7 @@ config SPI_XTENSA_XTFPGA
 
 config SPI_ZYNQMP_GQSPI
 	tristate "Xilinx ZynqMP GQSPI controller"
-	depends on SPI_MASTER
+	depends on SPI_MASTER && HAS_DMA
 	help
 	  Enables Xilinx GQSPI controller driver for Zynq UltraScale+ MPSoC.
 
diff --git a/drivers/spi/spi-img-spfi.c b/drivers/spi/spi-img-spfi.c
index 788e2b176a4f..00f1ac3d6a18 100644
--- a/drivers/spi/spi-img-spfi.c
+++ b/drivers/spi/spi-img-spfi.c
@@ -40,6 +40,7 @@
 #define SPFI_CONTROL_SOFT_RESET			BIT(11)
 #define SPFI_CONTROL_SEND_DMA			BIT(10)
 #define SPFI_CONTROL_GET_DMA			BIT(9)
+#define SPFI_CONTROL_SE			BIT(8)
 #define SPFI_CONTROL_TMODE_SHIFT		5
 #define SPFI_CONTROL_TMODE_MASK			0x7
 #define SPFI_CONTROL_TMODE_SINGLE		0
@@ -491,6 +492,7 @@ static void img_spfi_config(struct spi_master *master, struct spi_device *spi,
 	else if (xfer->tx_nbits == SPI_NBITS_QUAD &&
 		 xfer->rx_nbits == SPI_NBITS_QUAD)
 		val |= SPFI_CONTROL_TMODE_QUAD << SPFI_CONTROL_TMODE_SHIFT;
+	val |= SPFI_CONTROL_SE;
 	spfi_writel(spfi, val, SPFI_CONTROL);
 }
 
@@ -546,6 +548,7 @@ static int img_spfi_probe(struct platform_device *pdev)
 	struct img_spfi *spfi;
 	struct resource *res;
 	int ret;
+	u32 max_speed_hz;
 
 	master = spi_alloc_master(&pdev->dev, sizeof(*spfi));
 	if (!master)
@@ -610,6 +613,19 @@ static int img_spfi_probe(struct platform_device *pdev)
 	master->max_speed_hz = clk_get_rate(spfi->spfi_clk) / 4;
 	master->min_speed_hz = clk_get_rate(spfi->spfi_clk) / 512;
 
+	/*
+	 * Maximum speed supported by spfi is limited to the lower value
+	 * between 1/4 of the SPFI clock or to "spfi-max-frequency"
+	 * defined in the device tree.
+	 * If no value is defined in the device tree assume the maximum
+	 * speed supported to be 1/4 of the SPFI clock.
+	 */
+	if (!of_property_read_u32(spfi->dev->of_node, "spfi-max-frequency",
+				  &max_speed_hz)) {
+		if (master->max_speed_hz > max_speed_hz)
+			master->max_speed_hz = max_speed_hz;
+	}
+
 	master->setup = img_spfi_setup;
 	master->cleanup = img_spfi_cleanup;
 	master->transfer_one = img_spfi_transfer_one;
diff --git a/drivers/spi/spi-mpc512x-psc.c b/drivers/spi/spi-mpc512x-psc.c
index 965d2bdcfdcc..1e75341689a6 100644
--- a/drivers/spi/spi-mpc512x-psc.c
+++ b/drivers/spi/spi-mpc512x-psc.c
@@ -30,11 +30,37 @@
 #include <linux/gpio.h>
 #include <asm/mpc52xx_psc.h>
 
+enum {
+	TYPE_MPC5121,
+	TYPE_MPC5125,
+};
+
+/*
+ * This macro abstracts the differences in the PSC register layout between
+ * MPC5121 (which uses a struct mpc52xx_psc) and MPC5125 (using mpc5125_psc).
+ */
+#define psc_addr(mps, regname) ({					\
+	void *__ret = NULL;						\
+	switch (mps->type) {						\
+	case TYPE_MPC5121: {						\
+			struct mpc52xx_psc __iomem *psc = mps->psc;	\
+			__ret = &psc->regname;				\
+		};							\
+		break;							\
+	case TYPE_MPC5125: {						\
+			struct mpc5125_psc __iomem *psc = mps->psc;	\
+			__ret = &psc->regname;				\
+		};							\
+		break;							\
+	}								\
+	__ret; })
+
 struct mpc512x_psc_spi {
 	void (*cs_control)(struct spi_device *spi, bool on);
 
 	/* driver internal data */
-	struct mpc52xx_psc __iomem *psc;
+	int type;
+	void __iomem *psc;
 	struct mpc512x_psc_fifo __iomem *fifo;
 	unsigned int irq;
 	u8 bits_per_word;
@@ -71,13 +97,12 @@ static void mpc512x_psc_spi_activate_cs(struct spi_device *spi)
 {
 	struct mpc512x_psc_spi_cs *cs = spi->controller_state;
 	struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master);
-	struct mpc52xx_psc __iomem *psc = mps->psc;
 	u32 sicr;
 	u32 ccr;
 	int speed;
 	u16 bclkdiv;
 
-	sicr = in_be32(&psc->sicr);
+	sicr = in_be32(psc_addr(mps, sicr));
 
 	/* Set clock phase and polarity */
 	if (spi->mode & SPI_CPHA)
@@ -94,9 +119,9 @@ static void mpc512x_psc_spi_activate_cs(struct spi_device *spi)
 		sicr |= 0x10000000;
 	else
 		sicr &= ~0x10000000;
-	out_be32(&psc->sicr, sicr);
+	out_be32(psc_addr(mps, sicr), sicr);
 
-	ccr = in_be32(&psc->ccr);
+	ccr = in_be32(psc_addr(mps, ccr));
 	ccr &= 0xFF000000;
 	speed = cs->speed_hz;
 	if (!speed)
@@ -104,7 +129,7 @@ static void mpc512x_psc_spi_activate_cs(struct spi_device *spi)
 	bclkdiv = (mps->mclk_rate / speed) - 1;
 
 	ccr |= (((bclkdiv & 0xff) << 16) | (((bclkdiv >> 8) & 0xff) << 8));
-	out_be32(&psc->ccr, ccr);
+	out_be32(psc_addr(mps, ccr), ccr);
 	mps->bits_per_word = cs->bits_per_word;
 
 	if (mps->cs_control && gpio_is_valid(spi->cs_gpio))
@@ -315,16 +340,15 @@ static int mpc512x_psc_spi_msg_xfer(struct spi_master *master,
 static int mpc512x_psc_spi_prep_xfer_hw(struct spi_master *master)
 {
 	struct mpc512x_psc_spi *mps = spi_master_get_devdata(master);
-	struct mpc52xx_psc __iomem *psc = mps->psc;
 
 	dev_dbg(&master->dev, "%s()\n", __func__);
 
 	/* Zero MR2 */
-	in_8(&psc->mode);
-	out_8(&psc->mode, 0x0);
+	in_8(psc_addr(mps, mr2));
+	out_8(psc_addr(mps, mr2), 0x0);
 
 	/* enable transmitter/receiver */
-	out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
+	out_8(psc_addr(mps, command), MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
 
 	return 0;
 }
@@ -332,13 +356,12 @@ static int mpc512x_psc_spi_prep_xfer_hw(struct spi_master *master)
 static int mpc512x_psc_spi_unprep_xfer_hw(struct spi_master *master)
 {
 	struct mpc512x_psc_spi *mps = spi_master_get_devdata(master);
-	struct mpc52xx_psc __iomem *psc = mps->psc;
 	struct mpc512x_psc_fifo __iomem *fifo = mps->fifo;
 
 	dev_dbg(&master->dev, "%s()\n", __func__);
 
 	/* disable transmitter/receiver and fifo interrupt */
-	out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
+	out_8(psc_addr(mps, command), MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
 	out_be32(&fifo->tximr, 0);
 
 	return 0;
@@ -388,7 +411,6 @@ static void mpc512x_psc_spi_cleanup(struct spi_device *spi)
 static int mpc512x_psc_spi_port_config(struct spi_master *master,
 				       struct mpc512x_psc_spi *mps)
 {
-	struct mpc52xx_psc __iomem *psc = mps->psc;
 	struct mpc512x_psc_fifo __iomem *fifo = mps->fifo;
 	u32 sicr;
 	u32 ccr;
@@ -396,12 +418,12 @@ static int mpc512x_psc_spi_port_config(struct spi_master *master,
 	u16 bclkdiv;
 
 	/* Reset the PSC into a known state */
-	out_8(&psc->command, MPC52xx_PSC_RST_RX);
-	out_8(&psc->command, MPC52xx_PSC_RST_TX);
-	out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
+	out_8(psc_addr(mps, command), MPC52xx_PSC_RST_RX);
+	out_8(psc_addr(mps, command), MPC52xx_PSC_RST_TX);
+	out_8(psc_addr(mps, command), MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
 
 	/* Disable psc interrupts all useful interrupts are in fifo */
-	out_be16(&psc->isr_imr.imr, 0);
+	out_be16(psc_addr(mps, isr_imr.imr), 0);
 
 	/* Disable fifo interrupts, will be enabled later */
 	out_be32(&fifo->tximr, 0);
@@ -417,18 +439,18 @@ static int mpc512x_psc_spi_port_config(struct spi_master *master,
 		0x00004000 |	/* MSTR = 1   -- SPI master */
 		0x00000800;	/* UseEOF = 1 -- SS low until EOF */
 
-	out_be32(&psc->sicr, sicr);
+	out_be32(psc_addr(mps, sicr), sicr);
 
-	ccr = in_be32(&psc->ccr);
+	ccr = in_be32(psc_addr(mps, ccr));
 	ccr &= 0xFF000000;
 	speed = 1000000;	/* default 1MHz */
 	bclkdiv = (mps->mclk_rate / speed) - 1;
 	ccr |= (((bclkdiv & 0xff) << 16) | (((bclkdiv >> 8) & 0xff) << 8));
-	out_be32(&psc->ccr, ccr);
+	out_be32(psc_addr(mps, ccr), ccr);
 
 	/* Set 2ms DTL delay */
-	out_8(&psc->ctur, 0x00);
-	out_8(&psc->ctlr, 0x82);
+	out_8(psc_addr(mps, ctur), 0x00);
+	out_8(psc_addr(mps, ctlr), 0x82);
 
 	/* we don't use the alarms */
 	out_be32(&fifo->rxalarm, 0xfff);
@@ -482,6 +504,7 @@ static int mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr,
 
 	dev_set_drvdata(dev, master);
 	mps = spi_master_get_devdata(master);
+	mps->type = (int)of_device_get_match_data(dev);
 	mps->irq = irq;
 
 	if (pdata == NULL) {
@@ -589,7 +612,8 @@ static int mpc512x_psc_spi_of_remove(struct platform_device *op)
 }
 
 static const struct of_device_id mpc512x_psc_spi_of_match[] = {
-	{ .compatible = "fsl,mpc5121-psc-spi", },
+	{ .compatible = "fsl,mpc5121-psc-spi", .data = (void *)TYPE_MPC5121 },
+	{ .compatible = "fsl,mpc5125-psc-spi", .data = (void *)TYPE_MPC5125 },
 	{},
 };
 
diff --git a/drivers/spi/spi-pxa2xx-pci.c b/drivers/spi/spi-pxa2xx-pci.c
index 3cfd4357489a..d19d7f28aecb 100644
--- a/drivers/spi/spi-pxa2xx-pci.c
+++ b/drivers/spi/spi-pxa2xx-pci.c
@@ -7,7 +7,6 @@
 #include <linux/of_device.h>
 #include <linux/module.h>
 #include <linux/spi/pxa2xx_spi.h>
-#include <linux/clk.h>
 #include <linux/clk-provider.h>
 
 #include <linux/dmaengine.h>
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 68e7efeb9a27..79a8bc4f6cec 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -645,7 +645,6 @@ static int rockchip_spi_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, master);
 
 	rs = spi_master_get_devdata(master);
-	memset(rs, 0, sizeof(struct rockchip_spi));
 
 	/* Get basic io resource and map it */
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index f9189a0c8cec..818843336932 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -383,7 +383,8 @@ static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg)
 	rspi_write8(rspi, data, reg);
 }
 
-static int qspi_set_send_trigger(struct rspi_data *rspi, unsigned int len)
+static unsigned int qspi_set_send_trigger(struct rspi_data *rspi,
+					  unsigned int len)
 {
 	unsigned int n;
 
@@ -724,25 +725,25 @@ static int rspi_rz_transfer_one(struct spi_master *master,
 static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx,
 					u8 *rx, unsigned int len)
 {
-	int i, n, ret;
-	int error;
+	unsigned int i, n;
+	int ret;
 
 	while (len > 0) {
 		n = qspi_set_send_trigger(rspi, len);
 		qspi_set_receive_trigger(rspi, len);
 		if (n == QSPI_BUFFER_SIZE) {
-			error = rspi_wait_for_tx_empty(rspi);
-			if (error < 0) {
+			ret = rspi_wait_for_tx_empty(rspi);
+			if (ret < 0) {
 				dev_err(&rspi->master->dev, "transmit timeout\n");
-				return error;
+				return ret;
 			}
 			for (i = 0; i < n; i++)
 				rspi_write_data(rspi, *tx++);
 
-			error = rspi_wait_for_rx_full(rspi);
-			if (error < 0) {
+			ret = rspi_wait_for_rx_full(rspi);
+			if (ret < 0) {
 				dev_err(&rspi->master->dev, "receive timeout\n");
-				return error;
+				return ret;
 			}
 			for (i = 0; i < n; i++)
 				*rx++ = rspi_read_data(rspi);
diff --git a/drivers/spi/spi-s3c24xx.c b/drivers/spi/spi-s3c24xx.c
index f747ca269986..f36bc320a807 100644
--- a/drivers/spi/spi-s3c24xx.c
+++ b/drivers/spi/spi-s3c24xx.c
@@ -501,7 +501,6 @@ static int s3c24xx_spi_probe(struct platform_device *pdev)
 	}
 
 	hw = spi_master_get_devdata(master);
-	memset(hw, 0, sizeof(struct s3c24xx_spi));
 
 	hw->master = master;
 	hw->pdata = pdata = dev_get_platdata(&pdev->dev);
diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c
index d3370a612d84..118c652d88b5 100644
--- a/drivers/spi/spi-sh-msiof.c
+++ b/drivers/spi/spi-sh-msiof.c
@@ -1265,11 +1265,6 @@ static int sh_msiof_spi_remove(struct platform_device *pdev)
 
 static const struct platform_device_id spi_driver_ids[] = {
 	{ "spi_sh_msiof",	(kernel_ulong_t)&sh_data },
-	{ "spi_r8a7790_msiof",	(kernel_ulong_t)&r8a779x_data },
-	{ "spi_r8a7791_msiof",	(kernel_ulong_t)&r8a779x_data },
-	{ "spi_r8a7792_msiof",	(kernel_ulong_t)&r8a779x_data },
-	{ "spi_r8a7793_msiof",	(kernel_ulong_t)&r8a779x_data },
-	{ "spi_r8a7794_msiof",	(kernel_ulong_t)&r8a779x_data },
 	{},
 };
 MODULE_DEVICE_TABLE(platform, spi_driver_ids);
diff --git a/drivers/spi/spi-xcomm.c b/drivers/spi/spi-xcomm.c
index bb478dccf1d8..d0561a8d9f16 100644
--- a/drivers/spi/spi-xcomm.c
+++ b/drivers/spi/spi-xcomm.c
@@ -241,7 +241,6 @@ static const struct i2c_device_id spi_xcomm_ids[] = {
 static struct i2c_driver spi_xcomm_driver = {
 	.driver = {
 		.name	= "spi-xcomm",
-		.owner	= THIS_MODULE,
 	},
 	.id_table	= spi_xcomm_ids,
 	.probe		= spi_xcomm_probe,
diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c
index 87b20a511a6b..f23f36ebaf3d 100644
--- a/drivers/spi/spi-zynqmp-gqspi.c
+++ b/drivers/spi/spi-zynqmp-gqspi.c
@@ -214,6 +214,7 @@ static void zynqmp_gqspi_selectslave(struct zynqmp_qspi *instanceptr,
 	case GQSPI_SELECT_FLASH_CS_BOTH:
 		instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER |
 			GQSPI_GENFIFO_CS_UPPER;
+		break;
 	case GQSPI_SELECT_FLASH_CS_UPPER:
 		instanceptr->genfifocs = GQSPI_GENFIFO_CS_UPPER;
 		break;
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index cf8b91b23a76..766f48b9b70d 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -67,11 +67,141 @@ modalias_show(struct device *dev, struct device_attribute *a, char *buf)
 }
 static DEVICE_ATTR_RO(modalias);
 
+#define SPI_STATISTICS_ATTRS(field, file)				\
+static ssize_t spi_master_##field##_show(struct device *dev,		\
+					 struct device_attribute *attr,	\
+					 char *buf)			\
+{									\
+	struct spi_master *master = container_of(dev,			\
+						 struct spi_master, dev); \
+	return spi_statistics_##field##_show(&master->statistics, buf);	\
+}									\
+static struct device_attribute dev_attr_spi_master_##field = {		\
+	.attr = { .name = file, .mode = S_IRUGO },			\
+	.show = spi_master_##field##_show,				\
+};									\
+static ssize_t spi_device_##field##_show(struct device *dev,		\
+					 struct device_attribute *attr,	\
+					char *buf)			\
+{									\
+	struct spi_device *spi = container_of(dev,			\
+					      struct spi_device, dev);	\
+	return spi_statistics_##field##_show(&spi->statistics, buf);	\
+}									\
+static struct device_attribute dev_attr_spi_device_##field = {		\
+	.attr = { .name = file, .mode = S_IRUGO },			\
+	.show = spi_device_##field##_show,				\
+}
+
+#define SPI_STATISTICS_SHOW_NAME(name, file, field, format_string)	\
+static ssize_t spi_statistics_##name##_show(struct spi_statistics *stat, \
+					    char *buf)			\
+{									\
+	unsigned long flags;						\
+	ssize_t len;							\
+	spin_lock_irqsave(&stat->lock, flags);				\
+	len = sprintf(buf, format_string, stat->field);			\
+	spin_unlock_irqrestore(&stat->lock, flags);			\
+	return len;							\
+}									\
+SPI_STATISTICS_ATTRS(name, file)
+
+#define SPI_STATISTICS_SHOW(field, format_string)			\
+	SPI_STATISTICS_SHOW_NAME(field, __stringify(field),		\
+				 field, format_string)
+
+SPI_STATISTICS_SHOW(messages, "%lu");
+SPI_STATISTICS_SHOW(transfers, "%lu");
+SPI_STATISTICS_SHOW(errors, "%lu");
+SPI_STATISTICS_SHOW(timedout, "%lu");
+
+SPI_STATISTICS_SHOW(spi_sync, "%lu");
+SPI_STATISTICS_SHOW(spi_sync_immediate, "%lu");
+SPI_STATISTICS_SHOW(spi_async, "%lu");
+
+SPI_STATISTICS_SHOW(bytes, "%llu");
+SPI_STATISTICS_SHOW(bytes_rx, "%llu");
+SPI_STATISTICS_SHOW(bytes_tx, "%llu");
+
 static struct attribute *spi_dev_attrs[] = {
 	&dev_attr_modalias.attr,
 	NULL,
 };
-ATTRIBUTE_GROUPS(spi_dev);
+
+static const struct attribute_group spi_dev_group = {
+	.attrs  = spi_dev_attrs,
+};
+
+static struct attribute *spi_device_statistics_attrs[] = {
+	&dev_attr_spi_device_messages.attr,
+	&dev_attr_spi_device_transfers.attr,
+	&dev_attr_spi_device_errors.attr,
+	&dev_attr_spi_device_timedout.attr,
+	&dev_attr_spi_device_spi_sync.attr,
+	&dev_attr_spi_device_spi_sync_immediate.attr,
+	&dev_attr_spi_device_spi_async.attr,
+	&dev_attr_spi_device_bytes.attr,
+	&dev_attr_spi_device_bytes_rx.attr,
+	&dev_attr_spi_device_bytes_tx.attr,
+	NULL,
+};
+
+static const struct attribute_group spi_device_statistics_group = {
+	.name  = "statistics",
+	.attrs  = spi_device_statistics_attrs,
+};
+
+static const struct attribute_group *spi_dev_groups[] = {
+	&spi_dev_group,
+	&spi_device_statistics_group,
+	NULL,
+};
+
+static struct attribute *spi_master_statistics_attrs[] = {
+	&dev_attr_spi_master_messages.attr,
+	&dev_attr_spi_master_transfers.attr,
+	&dev_attr_spi_master_errors.attr,
+	&dev_attr_spi_master_timedout.attr,
+	&dev_attr_spi_master_spi_sync.attr,
+	&dev_attr_spi_master_spi_sync_immediate.attr,
+	&dev_attr_spi_master_spi_async.attr,
+	&dev_attr_spi_master_bytes.attr,
+	&dev_attr_spi_master_bytes_rx.attr,
+	&dev_attr_spi_master_bytes_tx.attr,
+	NULL,
+};
+
+static const struct attribute_group spi_master_statistics_group = {
+	.name  = "statistics",
+	.attrs  = spi_master_statistics_attrs,
+};
+
+static const struct attribute_group *spi_master_groups[] = {
+	&spi_master_statistics_group,
+	NULL,
+};
+
+void spi_statistics_add_transfer_stats(struct spi_statistics *stats,
+				       struct spi_transfer *xfer,
+				       struct spi_master *master)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&stats->lock, flags);
+
+	stats->transfers++;
+
+	stats->bytes += xfer->len;
+	if ((xfer->tx_buf) &&
+	    (xfer->tx_buf != master->dummy_tx))
+		stats->bytes_tx += xfer->len;
+	if ((xfer->rx_buf) &&
+	    (xfer->rx_buf != master->dummy_rx))
+		stats->bytes_rx += xfer->len;
+
+	spin_unlock_irqrestore(&stats->lock, flags);
+}
+EXPORT_SYMBOL_GPL(spi_statistics_add_transfer_stats);
 
 /* modalias support makes "modprobe $MODALIAS" new-style hotplug work,
  * and the sysfs version makes coldplug work too.
@@ -249,6 +379,9 @@ struct spi_device *spi_alloc_device(struct spi_master *master)
 	spi->dev.bus = &spi_bus_type;
 	spi->dev.release = spidev_release;
 	spi->cs_gpio = -ENOENT;
+
+	spin_lock_init(&spi->statistics.lock);
+
 	device_initialize(&spi->dev);
 	return spi;
 }
@@ -476,21 +609,30 @@ static int spi_map_buf(struct spi_master *master, struct device *dev,
 		       enum dma_data_direction dir)
 {
 	const bool vmalloced_buf = is_vmalloc_addr(buf);
-	const int desc_len = vmalloced_buf ? PAGE_SIZE : master->max_dma_len;
-	const int sgs = DIV_ROUND_UP(len, desc_len);
+	int desc_len;
+	int sgs;
 	struct page *vm_page;
 	void *sg_buf;
 	size_t min;
 	int i, ret;
 
+	if (vmalloced_buf) {
+		desc_len = PAGE_SIZE;
+		sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len);
+	} else {
+		desc_len = master->max_dma_len;
+		sgs = DIV_ROUND_UP(len, desc_len);
+	}
+
 	ret = sg_alloc_table(sgt, sgs, GFP_KERNEL);
 	if (ret != 0)
 		return ret;
 
 	for (i = 0; i < sgs; i++) {
-		min = min_t(size_t, len, desc_len);
 
 		if (vmalloced_buf) {
+			min = min_t(size_t,
+				    len, desc_len - offset_in_page(buf));
 			vm_page = vmalloc_to_page(buf);
 			if (!vm_page) {
 				sg_free_table(sgt);
@@ -499,6 +641,7 @@ static int spi_map_buf(struct spi_master *master, struct device *dev,
 			sg_set_page(&sgt->sgl[i], vm_page,
 				    min, offset_in_page(buf));
 		} else {
+			min = min_t(size_t, len, desc_len);
 			sg_buf = buf;
 			sg_set_buf(&sgt->sgl[i], sg_buf, min);
 		}
@@ -689,17 +832,29 @@ static int spi_transfer_one_message(struct spi_master *master,
 	bool keep_cs = false;
 	int ret = 0;
 	unsigned long ms = 1;
+	struct spi_statistics *statm = &master->statistics;
+	struct spi_statistics *stats = &msg->spi->statistics;
 
 	spi_set_cs(msg->spi, true);
 
+	SPI_STATISTICS_INCREMENT_FIELD(statm, messages);
+	SPI_STATISTICS_INCREMENT_FIELD(stats, messages);
+
 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
 		trace_spi_transfer_start(msg, xfer);
 
+		spi_statistics_add_transfer_stats(statm, xfer, master);
+		spi_statistics_add_transfer_stats(stats, xfer, master);
+
 		if (xfer->tx_buf || xfer->rx_buf) {
 			reinit_completion(&master->xfer_completion);
 
 			ret = master->transfer_one(master, msg->spi, xfer);
 			if (ret < 0) {
+				SPI_STATISTICS_INCREMENT_FIELD(statm,
+							       errors);
+				SPI_STATISTICS_INCREMENT_FIELD(stats,
+							       errors);
 				dev_err(&msg->spi->dev,
 					"SPI transfer failed: %d\n", ret);
 				goto out;
@@ -715,6 +870,10 @@ static int spi_transfer_one_message(struct spi_master *master,
 			}
 
 			if (ms == 0) {
+				SPI_STATISTICS_INCREMENT_FIELD(statm,
+							       timedout);
+				SPI_STATISTICS_INCREMENT_FIELD(stats,
+							       timedout);
 				dev_err(&msg->spi->dev,
 					"SPI transfer timed out\n");
 				msg->status = -ETIMEDOUT;
@@ -1416,10 +1575,10 @@ static struct class spi_master_class = {
 	.name		= "spi_master",
 	.owner		= THIS_MODULE,
 	.dev_release	= spi_master_release,
+	.dev_groups	= spi_master_groups,
 };
 
 
-
 /**
  * spi_alloc_master - allocate SPI master controller
  * @dev: the controller, possibly using the platform_bus
@@ -1585,6 +1744,8 @@ int spi_register_master(struct spi_master *master)
 			goto done;
 		}
 	}
+	/* add statistics */
+	spin_lock_init(&master->statistics.lock);
 
 	mutex_lock(&board_lock);
 	list_add_tail(&master->list, &spi_master_list);
@@ -1939,6 +2100,9 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message)
 
 	message->spi = spi;
 
+	SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, spi_async);
+	SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_async);
+
 	trace_spi_message_submit(message);
 
 	return master->transfer(spi, message);
@@ -2075,6 +2239,9 @@ static int __spi_sync(struct spi_device *spi, struct spi_message *message,
 	message->context = &done;
 	message->spi = spi;
 
+	SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, spi_sync);
+	SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_sync);
+
 	if (!bus_locked)
 		mutex_lock(&master->bus_lock_mutex);
 
@@ -2102,8 +2269,13 @@ static int __spi_sync(struct spi_device *spi, struct spi_message *message,
 		/* Push out the messages in the calling context if we
 		 * can.
 		 */
-		if (master->transfer == spi_queued_transfer)
+		if (master->transfer == spi_queued_transfer) {
+			SPI_STATISTICS_INCREMENT_FIELD(&master->statistics,
+						       spi_sync_immediate);
+			SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics,
+						       spi_sync_immediate);
 			__spi_pump_messages(master, false);
+		}
 
 		wait_for_completion(&done);
 		status = message->status;
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index dd616ff0ffc5..a902cc282de9 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -693,6 +693,7 @@ static struct class *spidev_class;
 #ifdef CONFIG_OF
 static const struct of_device_id spidev_dt_ids[] = {
 	{ .compatible = "rohm,dh2228fv" },
+	{ .compatible = "lineartechnology,ltc2488" },
 	{},
 };
 MODULE_DEVICE_TABLE(of, spidev_dt_ids);
@@ -708,7 +709,7 @@ static int spidev_probe(struct spi_device *spi)
 
 	/*
 	 * spidev should never be referenced in DT without a specific
-	 * compatbile string, it is a Linux implementation thing
+	 * compatible string, it is a Linux implementation thing
 	 * rather than a description of the hardware.
 	 */
 	if (spi->dev.of_node && !of_match_device(spidev_dt_ids, &spi->dev)) {
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index d673072346f2..269e8afd3e2a 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -23,6 +23,8 @@
 #include <linux/scatterlist.h>
 
 struct dma_chan;
+struct spi_master;
+struct spi_transfer;
 
 /*
  * INTERFACES between SPI master-side drivers and SPI infrastructure.
@@ -31,6 +33,59 @@ struct dma_chan;
 extern struct bus_type spi_bus_type;
 
 /**
+ * struct spi_statistics - statistics for spi transfers
+ * @clock:         lock protecting this structure
+ *
+ * @messages:      number of spi-messages handled
+ * @transfers:     number of spi_transfers handled
+ * @errors:        number of errors during spi_transfer
+ * @timedout:      number of timeouts during spi_transfer
+ *
+ * @spi_sync:      number of times spi_sync is used
+ * @spi_sync_immediate:
+ *                 number of times spi_sync is executed immediately
+ *                 in calling context without queuing and scheduling
+ * @spi_async:     number of times spi_async is used
+ *
+ * @bytes:         number of bytes transferred to/from device
+ * @bytes_tx:      number of bytes sent to device
+ * @bytes_rx:      number of bytes received from device
+ *
+ */
+struct spi_statistics {
+	spinlock_t		lock; /* lock for the whole structure */
+
+	unsigned long		messages;
+	unsigned long		transfers;
+	unsigned long		errors;
+	unsigned long		timedout;
+
+	unsigned long		spi_sync;
+	unsigned long		spi_sync_immediate;
+	unsigned long		spi_async;
+
+	unsigned long long	bytes;
+	unsigned long long	bytes_rx;
+	unsigned long long	bytes_tx;
+
+};
+
+void spi_statistics_add_transfer_stats(struct spi_statistics *stats,
+				       struct spi_transfer *xfer,
+				       struct spi_master *master);
+
+#define SPI_STATISTICS_ADD_TO_FIELD(stats, field, count)	\
+	do {							\
+		unsigned long flags;				\
+		spin_lock_irqsave(&(stats)->lock, flags);	\
+		(stats)->field += count;			\
+		spin_unlock_irqrestore(&(stats)->lock, flags);	\
+	} while (0)
+
+#define SPI_STATISTICS_INCREMENT_FIELD(stats, field)	\
+	SPI_STATISTICS_ADD_TO_FIELD(stats, field, 1)
+
+/**
  * struct spi_device - Master side proxy for an SPI slave device
  * @dev: Driver model representation of the device.
  * @master: SPI controller used with the device.
@@ -60,6 +115,8 @@ extern struct bus_type spi_bus_type;
  * @cs_gpio: gpio number of the chipselect line (optional, -ENOENT when
  *	when not using a GPIO line)
  *
+ * @statistics: statistics for the spi_device
+ *
  * A @spi_device is used to interchange data between an SPI slave
  * (usually a discrete chip) and CPU memory.
  *
@@ -98,6 +155,9 @@ struct spi_device {
 	char			modalias[SPI_NAME_SIZE];
 	int			cs_gpio;	/* chip select gpio */
 
+	/* the statistics */
+	struct spi_statistics	statistics;
+
 	/*
 	 * likely need more hooks for more protocol options affecting how
 	 * the controller talks to each chip, like:
@@ -296,6 +356,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
  * @cs_gpios: Array of GPIOs to use as chip select lines; one per CS
  *	number. Any individual value may be -ENOENT for CS lines that
  *	are not GPIOs (driven by the SPI controller itself).
+ * @statistics: statistics for the spi_master
  * @dma_tx: DMA transmit channel
  * @dma_rx: DMA receive channel
  * @dummy_rx: dummy receive buffer for full-duplex devices
@@ -452,6 +513,9 @@ struct spi_master {
 	/* gpio chip select */
 	int			*cs_gpios;
 
+	/* statistics */
+	struct spi_statistics	statistics;
+
 	/* DMA channels for use with core dmaengine helpers */
 	struct dma_chan		*dma_tx;
 	struct dma_chan		*dma_rx;