spi: Header and core clean up and refactoring

Merge series from Andy Shevchenko <andriy.shevchenko@linux.intel.com>:

Various cleanups and refactorings of the SPI header and core parts
united in a single series. It also touches drivers under SPI subsystem
folder on the pure renaming purposes of some constants.

No functional change intended.

34 files changed, 130 insertions, 142 deletions

diff --git a/drivers/spi/spi-amd.c b/drivers/spi/spi-amd.c
index fecead757a3c..b19766571f28 100644
--- a/drivers/spi/spi-amd.c
+++ b/drivers/spi/spi-amd.c
@@ -404,7 +404,7 @@ static int amd_spi_probe(struct platform_device *pdev)
 	master->bus_num = 0;
 	master->num_chipselect = 4;
 	master->mode_bits = 0;
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	master->max_speed_hz = AMD_SPI_MAX_HZ;
 	master->min_speed_hz = AMD_SPI_MIN_HZ;
 	master->setup = amd_spi_master_setup;
diff --git a/drivers/spi/spi-at91-usart.c b/drivers/spi/spi-at91-usart.c
index 7854d9790fe9..7dfe2b6c2990 100644
--- a/drivers/spi/spi-at91-usart.c
+++ b/drivers/spi/spi-at91-usart.c
@@ -527,7 +527,7 @@ static int at91_usart_spi_probe(struct platform_device *pdev)
 	controller->dev.of_node = pdev->dev.parent->of_node;
 	controller->bits_per_word_mask = SPI_BPW_MASK(8);
 	controller->setup = at91_usart_spi_setup;
-	controller->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;
+	controller->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
 	controller->transfer_one = at91_usart_spi_transfer_one;
 	controller->prepare_message = at91_usart_spi_prepare_message;
 	controller->unprepare_message = at91_usart_spi_unprepare_message;
diff --git a/drivers/spi/spi-ath79.c b/drivers/spi/spi-ath79.c
index d3dd21386f12..1b6d977d111c 100644
--- a/drivers/spi/spi-ath79.c
+++ b/drivers/spi/spi-ath79.c
@@ -185,7 +185,7 @@ static int ath79_spi_probe(struct platform_device *pdev)
 
 	host->use_gpio_descriptors = true;
 	host->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
-	host->flags = SPI_MASTER_GPIO_SS;
+	host->flags = SPI_CONTROLLER_GPIO_SS;
 	host->num_chipselect = 3;
 	host->mem_ops = &ath79_mem_ops;
 
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 8a9c8b92be8c..6aa8adbe4170 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -1471,8 +1471,8 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	host->bus_num = pdev->id;
 	host->num_chipselect = 4;
 	host->setup = atmel_spi_setup;
-	host->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX |
-			SPI_MASTER_GPIO_SS);
+	host->flags = (SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX |
+			SPI_CONTROLLER_GPIO_SS);
 	host->transfer_one = atmel_spi_one_transfer;
 	host->set_cs = atmel_spi_set_cs;
 	host->cleanup = atmel_spi_cleanup;
diff --git a/drivers/spi/spi-bitbang-txrx.h b/drivers/spi/spi-bitbang-txrx.h
index 2dcbe166df63..0cab48b7875b 100644
--- a/drivers/spi/spi-bitbang-txrx.h
+++ b/drivers/spi/spi-bitbang-txrx.h
@@ -57,7 +57,7 @@ bitbang_txrx_be_cpha0(struct spi_device *spi,
 	for (word <<= (32 - bits); likely(bits); bits--) {
 
 		/* setup MSB (to slave) on trailing edge */
-		if ((flags & SPI_MASTER_NO_TX) == 0) {
+		if ((flags & SPI_CONTROLLER_NO_TX) == 0) {
 			if ((word & (1 << 31)) != oldbit) {
 				setmosi(spi, word & (1 << 31));
 				oldbit = word & (1 << 31);
@@ -70,7 +70,7 @@ bitbang_txrx_be_cpha0(struct spi_device *spi,
 
 		/* sample MSB (from slave) on leading edge */
 		word <<= 1;
-		if ((flags & SPI_MASTER_NO_RX) == 0)
+		if ((flags & SPI_CONTROLLER_NO_RX) == 0)
 			word |= getmiso(spi);
 		setsck(spi, cpol);
 	}
@@ -90,7 +90,7 @@ bitbang_txrx_be_cpha1(struct spi_device *spi,
 
 		/* setup MSB (to slave) on leading edge */
 		setsck(spi, !cpol);
-		if ((flags & SPI_MASTER_NO_TX) == 0) {
+		if ((flags & SPI_CONTROLLER_NO_TX) == 0) {
 			if ((word & (1 << 31)) != oldbit) {
 				setmosi(spi, word & (1 << 31));
 				oldbit = word & (1 << 31);
@@ -103,7 +103,7 @@ bitbang_txrx_be_cpha1(struct spi_device *spi,
 
 		/* sample MSB (from slave) on trailing edge */
 		word <<= 1;
-		if ((flags & SPI_MASTER_NO_RX) == 0)
+		if ((flags & SPI_CONTROLLER_NO_RX) == 0)
 			word |= getmiso(spi);
 	}
 	return word;
@@ -122,7 +122,7 @@ bitbang_txrx_le_cpha0(struct spi_device *spi,
 	for (; likely(bits); bits--) {
 
 		/* setup LSB (to slave) on trailing edge */
-		if ((flags & SPI_MASTER_NO_TX) == 0) {
+		if ((flags & SPI_CONTROLLER_NO_TX) == 0) {
 			if ((word & 1) != oldbit) {
 				setmosi(spi, word & 1);
 				oldbit = word & 1;
@@ -135,7 +135,7 @@ bitbang_txrx_le_cpha0(struct spi_device *spi,
 
 		/* sample LSB (from slave) on leading edge */
 		word >>= 1;
-		if ((flags & SPI_MASTER_NO_RX) == 0)
+		if ((flags & SPI_CONTROLLER_NO_RX) == 0)
 			word |= getmiso(spi) << rxbit;
 		setsck(spi, cpol);
 	}
@@ -156,7 +156,7 @@ bitbang_txrx_le_cpha1(struct spi_device *spi,
 
 		/* setup LSB (to slave) on leading edge */
 		setsck(spi, !cpol);
-		if ((flags & SPI_MASTER_NO_TX) == 0) {
+		if ((flags & SPI_CONTROLLER_NO_TX) == 0) {
 			if ((word & 1) != oldbit) {
 				setmosi(spi, word & 1);
 				oldbit = word & 1;
@@ -169,7 +169,7 @@ bitbang_txrx_le_cpha1(struct spi_device *spi,
 
 		/* sample LSB (from slave) on trailing edge */
 		word >>= 1;
-		if ((flags & SPI_MASTER_NO_RX) == 0)
+		if ((flags & SPI_CONTROLLER_NO_RX) == 0)
 			word |= getmiso(spi) << rxbit;
 	}
 	return word;
diff --git a/drivers/spi/spi-bitbang.c b/drivers/spi/spi-bitbang.c
index 27d0087f8688..ecd44016c197 100644
--- a/drivers/spi/spi-bitbang.c
+++ b/drivers/spi/spi-bitbang.c
@@ -248,7 +248,7 @@ static int spi_bitbang_bufs(struct spi_device *spi, struct spi_transfer *t)
 	if (spi->mode & SPI_3WIRE) {
 		unsigned flags;
 
-		flags = t->tx_buf ? SPI_MASTER_NO_RX : SPI_MASTER_NO_TX;
+		flags = t->tx_buf ? SPI_CONTROLLER_NO_RX : SPI_CONTROLLER_NO_TX;
 		return cs->txrx_bufs(spi, cs->txrx_word, nsecs, t, flags);
 	}
 	return cs->txrx_bufs(spi, cs->txrx_word, nsecs, t, 0);
@@ -349,11 +349,11 @@ int spi_bitbang_init(struct spi_bitbang *bitbang)
 	/*
 	 * We only need the chipselect callback if we are actually using it.
 	 * If we just use GPIO descriptors, it is surplus. If the
-	 * SPI_MASTER_GPIO_SS flag is set, we always need to call the
+	 * SPI_CONTROLLER_GPIO_SS flag is set, we always need to call the
 	 * driver-specific chipselect routine.
 	 */
 	custom_cs = (!master->use_gpio_descriptors ||
-		     (master->flags & SPI_MASTER_GPIO_SS));
+		     (master->flags & SPI_CONTROLLER_GPIO_SS));
 
 	if (custom_cs && !bitbang->chipselect)
 		return -EINVAL;
@@ -371,7 +371,7 @@ int spi_bitbang_init(struct spi_bitbang *bitbang)
 	master->transfer_one = spi_bitbang_transfer_one;
 	/*
 	 * When using GPIO descriptors, the ->set_cs() callback doesn't even
-	 * get called unless SPI_MASTER_GPIO_SS is set.
+	 * get called unless SPI_CONTROLLER_GPIO_SS is set.
 	 */
 	if (custom_cs)
 		master->set_cs = spi_bitbang_set_cs;
diff --git a/drivers/spi/spi-cavium-thunderx.c b/drivers/spi/spi-cavium-thunderx.c
index 60c0d6934654..535f7eb9fa69 100644
--- a/drivers/spi/spi-cavium-thunderx.c
+++ b/drivers/spi/spi-cavium-thunderx.c
@@ -64,7 +64,7 @@ static int thunderx_spi_probe(struct pci_dev *pdev,
 		p->sys_freq = SYS_FREQ_DEFAULT;
 	dev_info(dev, "Set system clock to %u\n", p->sys_freq);
 
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	master->num_chipselect = 4;
 	master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH |
 			    SPI_LSB_FIRST | SPI_3WIRE;
diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c
index a85fd0cb4a5e..a3470cbaabdc 100644
--- a/drivers/spi/spi-davinci.c
+++ b/drivers/spi/spi-davinci.c
@@ -930,7 +930,7 @@ static int davinci_spi_probe(struct platform_device *pdev)
 	master->bus_num = pdev->id;
 	master->num_chipselect = pdata->num_chipselect;
 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(2, 16);
-	master->flags = SPI_MASTER_MUST_RX | SPI_MASTER_GPIO_SS;
+	master->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_GPIO_SS;
 	master->setup = davinci_spi_setup;
 	master->cleanup = davinci_spi_cleanup;
 	master->can_dma = davinci_spi_can_dma;
diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c
index a8ba41ad4541..45f5acc26b1d 100644
--- a/drivers/spi/spi-dw-core.c
+++ b/drivers/spi/spi-dw-core.c
@@ -932,7 +932,7 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
 	if (dws->mem_ops.exec_op)
 		master->mem_ops = &dws->mem_ops;
 	master->max_speed_hz = dws->max_freq;
-	master->flags = SPI_MASTER_GPIO_SS;
+	master->flags = SPI_CONTROLLER_GPIO_SS;
 	master->auto_runtime_pm = true;
 
 	/* Get default rx sample delay */
diff --git a/drivers/spi/spi-falcon.c b/drivers/spi/spi-falcon.c
index 4c103dff0d44..8a8414cbb400 100644
--- a/drivers/spi/spi-falcon.c
+++ b/drivers/spi/spi-falcon.c
@@ -401,7 +401,7 @@ static int falcon_sflash_probe(struct platform_device *pdev)
 	priv->master = master;
 
 	master->mode_bits = SPI_MODE_3;
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	master->setup = falcon_sflash_setup;
 	master->transfer_one_message = falcon_sflash_xfer_one;
 	master->dev.of_node = pdev->dev.of_node;
diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index fb68c72df171..1c907d5d5bb3 100644
--- a/drivers/spi/spi-fsl-lpspi.c
+++ b/drivers/spi/spi-fsl-lpspi.c
@@ -856,7 +856,7 @@ static int fsl_lpspi_probe(struct platform_device *pdev)
 	controller->prepare_transfer_hardware = lpspi_prepare_xfer_hardware;
 	controller->unprepare_transfer_hardware = lpspi_unprepare_xfer_hardware;
 	controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
-	controller->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;
+	controller->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
 	controller->dev.of_node = pdev->dev.of_node;
 	controller->bus_num = pdev->id;
 	controller->num_chipselect = fsl_lpspi->num_cs;
diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index 092afc7679d4..612db477ad12 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -170,7 +170,7 @@ static u32 spi_gpio_txrx_word_mode3(struct spi_device *spi,
 
 /*
  * These functions do not call setmosi or getmiso if respective flag
- * (SPI_MASTER_NO_RX or SPI_MASTER_NO_TX) is set, so they are safe to
+ * (SPI_CONTROLLER_NO_RX or SPI_CONTROLLER_NO_TX) is set, so they are safe to
  * call when such pin is not present or defined in the controller.
  * A separate set of callbacks is defined to get highest possible
  * speed in the generic case (when both MISO and MOSI lines are
@@ -416,11 +416,11 @@ static int spi_gpio_probe(struct platform_device *pdev)
 	if (!spi_gpio->mosi) {
 		/* HW configuration without MOSI pin
 		 *
-		 * No setting SPI_MASTER_NO_RX here - if there is only
+		 * No setting SPI_CONTROLLER_NO_RX here - if there is only
 		 * a MOSI pin connected the host can still do RX by
 		 * changing the direction of the line.
 		 */
-		master->flags = SPI_MASTER_NO_TX;
+		master->flags = SPI_CONTROLLER_NO_TX;
 	}
 
 	master->bus_num = pdev->id;
@@ -434,11 +434,11 @@ static int spi_gpio_probe(struct platform_device *pdev)
 	 * line, that we need to do on selection. This makes the local
 	 * callback for chipselect always get called.
 	 */
-	master->flags |= SPI_MASTER_GPIO_SS;
+	master->flags |= SPI_CONTROLLER_GPIO_SS;
 	bb->chipselect = spi_gpio_chipselect;
 	bb->set_line_direction = spi_gpio_set_direction;
 
-	if (master->flags & SPI_MASTER_NO_TX) {
+	if (master->flags & SPI_CONTROLLER_NO_TX) {
 		bb->txrx_word[SPI_MODE_0] = spi_gpio_spec_txrx_word_mode0;
 		bb->txrx_word[SPI_MODE_1] = spi_gpio_spec_txrx_word_mode1;
 		bb->txrx_word[SPI_MODE_2] = spi_gpio_spec_txrx_word_mode2;
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index 169d158b6f00..db22f685ce91 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -1784,7 +1784,7 @@ static int spi_imx_probe(struct platform_device *pdev)
 
 	if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx)) {
 		controller->max_native_cs = 4;
-		controller->flags |= SPI_MASTER_GPIO_SS;
+		controller->flags |= SPI_CONTROLLER_GPIO_SS;
 	}
 
 	spi_imx->spi_drctl = spi_drctl;
diff --git a/drivers/spi/spi-lp8841-rtc.c b/drivers/spi/spi-lp8841-rtc.c
index 2d436541d6c2..c6810720b3b5 100644
--- a/drivers/spi/spi-lp8841-rtc.c
+++ b/drivers/spi/spi-lp8841-rtc.c
@@ -75,14 +75,14 @@ bitbang_txrx_be_cpha0_lsb(struct spi_lp8841_rtc *data,
 	for (; likely(bits); bits--) {
 
 		/* setup LSB (to slave) on leading edge */
-		if ((flags & SPI_MASTER_NO_TX) == 0)
+		if ((flags & SPI_CONTROLLER_NO_TX) == 0)
 			setmosi(data, (word & 1));
 
 		usleep_range(usecs, usecs + 1);	/* T(setup) */
 
 		/* sample LSB (from slave) on trailing edge */
 		word >>= 1;
-		if ((flags & SPI_MASTER_NO_RX) == 0)
+		if ((flags & SPI_CONTROLLER_NO_RX) == 0)
 			word |= (getmiso(data) << 31);
 
 		setsck(data, !cpol);
@@ -113,7 +113,7 @@ spi_lp8841_rtc_transfer_one(struct spi_master *master,
 		while (likely(count > 0)) {
 			word = *tx++;
 			bitbang_txrx_be_cpha0_lsb(data, 1, 0,
-					SPI_MASTER_NO_RX, word, 8);
+					SPI_CONTROLLER_NO_RX, word, 8);
 			count--;
 		}
 	} else if (rx) {
@@ -121,7 +121,7 @@ spi_lp8841_rtc_transfer_one(struct spi_master *master,
 		writeb(data->state, data->iomem);
 		while (likely(count > 0)) {
 			word = bitbang_txrx_be_cpha0_lsb(data, 1, 0,
-					SPI_MASTER_NO_TX, word, 8);
+					SPI_CONTROLLER_NO_TX, word, 8);
 			*rx++ = word;
 			count--;
 		}
@@ -191,7 +191,7 @@ spi_lp8841_rtc_probe(struct platform_device *pdev)
 		return -ENOMEM;
 	platform_set_drvdata(pdev, master);
 
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	master->mode_bits = SPI_CS_HIGH | SPI_3WIRE | SPI_LSB_FIRST;
 
 	master->bus_num = pdev->id;
diff --git a/drivers/spi/spi-meson-spicc.c b/drivers/spi/spi-meson-spicc.c
index 141562c882f1..7a9eba35ac38 100644
--- a/drivers/spi/spi-meson-spicc.c
+++ b/drivers/spi/spi-meson-spicc.c
@@ -864,7 +864,7 @@ static int meson_spicc_probe(struct platform_device *pdev)
 				     SPI_BPW_MASK(24) |
 				     SPI_BPW_MASK(16) |
 				     SPI_BPW_MASK(8);
-	master->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX);
+	master->flags = (SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX);
 	master->min_speed_hz = spicc->data->min_speed_hz;
 	master->max_speed_hz = spicc->data->max_speed_hz;
 	master->setup = meson_spicc_setup;
diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
index 39272ad6641b..0757985947dd 100644
--- a/drivers/spi/spi-mt65xx.c
+++ b/drivers/spi/spi-mt65xx.c
@@ -1142,7 +1142,7 @@ static int mtk_spi_probe(struct platform_device *pdev)
 		master->mode_bits |= SPI_CS_HIGH;
 
 	if (mdata->dev_comp->must_tx)
-		master->flags = SPI_MASTER_MUST_TX;
+		master->flags = SPI_CONTROLLER_MUST_TX;
 	if (mdata->dev_comp->ipm_design)
 		master->mode_bits |= SPI_LOOP | SPI_RX_DUAL | SPI_TX_DUAL |
 				     SPI_RX_QUAD | SPI_TX_QUAD;
diff --git a/drivers/spi/spi-mxs.c b/drivers/spi/spi-mxs.c
index 963a53dd680b..cd0e7ae07162 100644
--- a/drivers/spi/spi-mxs.c
+++ b/drivers/spi/spi-mxs.c
@@ -572,7 +572,7 @@ static int mxs_spi_probe(struct platform_device *pdev)
 	master->mode_bits = SPI_CPOL | SPI_CPHA;
 	master->num_chipselect = 3;
 	master->dev.of_node = np;
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	master->auto_runtime_pm = true;
 
 	spi = spi_master_get_devdata(master);
diff --git a/drivers/spi/spi-omap-uwire.c b/drivers/spi/spi-omap-uwire.c
index 902d2e0c1f2f..f89aa9e52c23 100644
--- a/drivers/spi/spi-omap-uwire.c
+++ b/drivers/spi/spi-omap-uwire.c
@@ -486,7 +486,7 @@ static int uwire_probe(struct platform_device *pdev)
 	/* the spi->mode bits understood by this driver: */
 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16);
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 
 	master->bus_num = 2;	/* "official" */
 	master->num_chipselect = 4;
diff --git a/drivers/spi/spi-orion.c b/drivers/spi/spi-orion.c
index ad9e83e34297..4882aafd0505 100644
--- a/drivers/spi/spi-orion.c
+++ b/drivers/spi/spi-orion.c
@@ -677,7 +677,7 @@ static int orion_spi_probe(struct platform_device *pdev)
 	master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
 	master->auto_runtime_pm = true;
 	master->use_gpio_descriptors = true;
-	master->flags = SPI_MASTER_GPIO_SS;
+	master->flags = SPI_CONTROLLER_GPIO_SS;
 
 	platform_set_drvdata(pdev, master);
 
diff --git a/drivers/spi/spi-pci1xxxx.c b/drivers/spi/spi-pci1xxxx.c
index 4445d82409d6..d23c42839da1 100644
--- a/drivers/spi/spi-pci1xxxx.c
+++ b/drivers/spi/spi-pci1xxxx.c
@@ -365,7 +365,7 @@ static int pci1xxxx_spi_probe(struct pci_dev *pdev, const struct pci_device_id *
 		spi_host->bits_per_word_mask = SPI_BPW_MASK(8);
 		spi_host->max_speed_hz = PCI1XXXX_SPI_MAX_CLOCK_HZ;
 		spi_host->min_speed_hz = PCI1XXXX_SPI_MIN_CLOCK_HZ;
-		spi_host->flags = SPI_MASTER_MUST_TX;
+		spi_host->flags = SPI_CONTROLLER_MUST_TX;
 		spi_master_set_devdata(spi_host, spi_sub_ptr);
 		ret = devm_spi_register_master(dev, spi_host);
 		if (ret)
diff --git a/drivers/spi/spi-pic32-sqi.c b/drivers/spi/spi-pic32-sqi.c
index 51dfb49523f3..5cbebcf26a2a 100644
--- a/drivers/spi/spi-pic32-sqi.c
+++ b/drivers/spi/spi-pic32-sqi.c
@@ -648,7 +648,7 @@ static int pic32_sqi_probe(struct platform_device *pdev)
 	master->dev.of_node	= pdev->dev.of_node;
 	master->mode_bits	= SPI_MODE_3 | SPI_MODE_0 | SPI_TX_DUAL |
 				  SPI_RX_DUAL | SPI_TX_QUAD | SPI_RX_QUAD;
-	master->flags		= SPI_MASTER_HALF_DUPLEX;
+	master->flags		= SPI_CONTROLLER_HALF_DUPLEX;
 	master->can_dma		= pic32_sqi_can_dma;
 	master->bits_per_word_mask	= SPI_BPW_RANGE_MASK(8, 32);
 	master->transfer_one_message	= pic32_sqi_one_message;
diff --git a/drivers/spi/spi-pic32.c b/drivers/spi/spi-pic32.c
index f2af5e653f3d..e9b4c9cb97fb 100644
--- a/drivers/spi/spi-pic32.c
+++ b/drivers/spi/spi-pic32.c
@@ -773,7 +773,7 @@ static int pic32_spi_probe(struct platform_device *pdev)
 	master->max_speed_hz	= clk_get_rate(pic32s->clk);
 	master->setup		= pic32_spi_setup;
 	master->cleanup		= pic32_spi_cleanup;
-	master->flags		= SPI_MASTER_MUST_TX | SPI_MASTER_MUST_RX;
+	master->flags		= SPI_CONTROLLER_MUST_TX | SPI_CONTROLLER_MUST_RX;
 	master->bits_per_word_mask	= SPI_BPW_MASK(8) | SPI_BPW_MASK(16) |
 					  SPI_BPW_MASK(32);
 	master->transfer_one		= pic32_spi_one_transfer;
diff --git a/drivers/spi/spi-qcom-qspi.c b/drivers/spi/spi-qcom-qspi.c
index a8a683d6145c..5a98c52bad32 100644
--- a/drivers/spi/spi-qcom-qspi.c
+++ b/drivers/spi/spi-qcom-qspi.c
@@ -724,7 +724,7 @@ static int qcom_qspi_probe(struct platform_device *pdev)
 	master->mode_bits = SPI_MODE_0 |
 			    SPI_TX_DUAL | SPI_RX_DUAL |
 			    SPI_TX_QUAD | SPI_RX_QUAD;
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	master->prepare_message = qcom_qspi_prepare_message;
 	master->transfer_one = qcom_qspi_transfer_one;
 	master->handle_err = qcom_qspi_handle_err;
diff --git a/drivers/spi/spi-rb4xx.c b/drivers/spi/spi-rb4xx.c
index 5073736d3d1f..c817889a7797 100644
--- a/drivers/spi/spi-rb4xx.c
+++ b/drivers/spi/spi-rb4xx.c
@@ -156,7 +156,7 @@ static int rb4xx_spi_probe(struct platform_device *pdev)
 	master->num_chipselect = 3;
 	master->mode_bits = SPI_TX_DUAL;
 	master->bits_per_word_mask = SPI_BPW_MASK(8);
-	master->flags = SPI_MASTER_MUST_TX;
+	master->flags = SPI_CONTROLLER_MUST_TX;
 	master->transfer_one = rb4xx_transfer_one;
 	master->set_cs = rb4xx_set_cs;
 
diff --git a/drivers/spi/spi-rockchip-sfc.c b/drivers/spi/spi-rockchip-sfc.c
index 583f4187f030..bd550e76ab3d 100644
--- a/drivers/spi/spi-rockchip-sfc.c
+++ b/drivers/spi/spi-rockchip-sfc.c
@@ -565,7 +565,7 @@ static int rockchip_sfc_probe(struct platform_device *pdev)
 	if (!master)
 		return -ENOMEM;
 
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	master->mem_ops = &rockchip_sfc_mem_ops;
 	master->dev.of_node = pdev->dev.of_node;
 	master->mode_bits = SPI_TX_QUAD | SPI_TX_DUAL | SPI_RX_QUAD | SPI_RX_DUAL;
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 143ede958ac1..a37943847e81 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -858,7 +858,7 @@ static int rockchip_spi_probe(struct platform_device *pdev)
 		ctlr->mode_bits |= SPI_NO_CS;
 		ctlr->slave_abort = rockchip_spi_slave_abort;
 	} else {
-		ctlr->flags = SPI_MASTER_GPIO_SS;
+		ctlr->flags = SPI_CONTROLLER_GPIO_SS;
 		ctlr->max_native_cs = ROCKCHIP_SPI_MAX_CS_NUM;
 		/*
 		 * rk spi0 has two native cs, spi1..5 one cs only
diff --git a/drivers/spi/spi-sifive.c b/drivers/spi/spi-sifive.c
index dae9e097c333..2f77dae85386 100644
--- a/drivers/spi/spi-sifive.c
+++ b/drivers/spi/spi-sifive.c
@@ -379,7 +379,7 @@ static int sifive_spi_probe(struct platform_device *pdev)
 	 * we need to "left-align" the bits (unless SPI_LSB_FIRST)
 	 */
 	master->bits_per_word_mask = SPI_BPW_MASK(8);
-	master->flags = SPI_CONTROLLER_MUST_TX | SPI_MASTER_GPIO_SS;
+	master->flags = SPI_CONTROLLER_MUST_TX | SPI_CONTROLLER_GPIO_SS;
 	master->prepare_message = sifive_spi_prepare_message;
 	master->set_cs = sifive_spi_set_cs;
 	master->transfer_one = sifive_spi_transfer_one;
diff --git a/drivers/spi/spi-slave-mt27xx.c b/drivers/spi/spi-slave-mt27xx.c
index 4e4d426bfb43..6d6772974783 100644
--- a/drivers/spi/spi-slave-mt27xx.c
+++ b/drivers/spi/spi-slave-mt27xx.c
@@ -414,7 +414,7 @@ static int mtk_spi_slave_probe(struct platform_device *pdev)
 	mdata->dev_comp = of_id->data;
 
 	if (mdata->dev_comp->must_rx)
-		ctlr->flags = SPI_MASTER_MUST_RX;
+		ctlr->flags = SPI_CONTROLLER_MUST_RX;
 
 	platform_set_drvdata(pdev, ctlr);
 
diff --git a/drivers/spi/spi-sprd-adi.c b/drivers/spi/spi-sprd-adi.c
index 22e39c4c12c4..94d16aadfa44 100644
--- a/drivers/spi/spi-sprd-adi.c
+++ b/drivers/spi/spi-sprd-adi.c
@@ -580,7 +580,7 @@ static int sprd_adi_probe(struct platform_device *pdev)
 	ctlr->dev.of_node = pdev->dev.of_node;
 	ctlr->bus_num = pdev->id;
 	ctlr->num_chipselect = num_chipselect;
-	ctlr->flags = SPI_MASTER_HALF_DUPLEX;
+	ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	ctlr->bits_per_word_mask = 0;
 	ctlr->transfer_one = sprd_adi_transfer_one;
 
diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index 536d89e044cf..8cf7b41481b2 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -1753,7 +1753,7 @@ static const struct stm32_spi_cfg stm32f4_spi_cfg = {
 	.baud_rate_div_max = STM32F4_SPI_BR_DIV_MAX,
 	.has_fifo = false,
 	.has_device_mode = false,
-	.flags = SPI_MASTER_MUST_TX,
+	.flags = SPI_CONTROLLER_MUST_TX,
 };
 
 static const struct stm32_spi_cfg stm32h7_spi_cfg = {
diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c
index 5914335ff63d..bf4b40289bee 100644
--- a/drivers/spi/spi-ti-qspi.c
+++ b/drivers/spi/spi-ti-qspi.c
@@ -770,7 +770,7 @@ static int ti_qspi_probe(struct platform_device *pdev)
 
 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD;
 
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	master->setup = ti_qspi_setup;
 	master->auto_runtime_pm = true;
 	master->transfer_one_message = ti_qspi_start_transfer_one;
diff --git a/drivers/spi/spi-xcomm.c b/drivers/spi/spi-xcomm.c
index ae6218bcd02a..a3d57554f5ba 100644
--- a/drivers/spi/spi-xcomm.c
+++ b/drivers/spi/spi-xcomm.c
@@ -218,7 +218,7 @@ static int spi_xcomm_probe(struct i2c_client *i2c)
 	master->num_chipselect = 16;
 	master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_3WIRE;
 	master->bits_per_word_mask = SPI_BPW_MASK(8);
-	master->flags = SPI_MASTER_HALF_DUPLEX;
+	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
 	master->transfer_one_message = spi_xcomm_transfer_one;
 	master->dev.of_node = i2c->dev.of_node;
 	i2c_set_clientdata(i2c, master);
diff --git a/drivers/spi/spi-xtensa-xtfpga.c b/drivers/spi/spi-xtensa-xtfpga.c
index 24dc845b940e..dbd85d7a1526 100644
--- a/drivers/spi/spi-xtensa-xtfpga.c
+++ b/drivers/spi/spi-xtensa-xtfpga.c
@@ -87,7 +87,7 @@ static int xtfpga_spi_probe(struct platform_device *pdev)
 	if (!master)
 		return -ENOMEM;
 
-	master->flags = SPI_MASTER_NO_RX;
+	master->flags = SPI_CONTROLLER_NO_RX;
 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 16);
 	master->bus_num = pdev->dev.id;
 	master->dev.of_node = pdev->dev.of_node;
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 9291b2a0e887..ae2693ba1744 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -4,36 +4,36 @@
 // Copyright (C) 2005 David Brownell
 // Copyright (C) 2008 Secret Lab Technologies Ltd.
 
-#include <linux/kernel.h>
-#include <linux/device.h>
-#include <linux/init.h>
+#include <linux/acpi.h>
 #include <linux/cache.h>
-#include <linux/dma-mapping.h>
+#include <linux/clk/clk-conf.h>
+#include <linux/delay.h>
+#include <linux/device.h>
 #include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/export.h>
+#include <linux/gpio/consumer.h>
+#include <linux/highmem.h>
+#include <linux/idr.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/mod_devicetable.h>
 #include <linux/mutex.h>
 #include <linux/of_device.h>
 #include <linux/of_irq.h>
-#include <linux/clk/clk-conf.h>
-#include <linux/slab.h>
-#include <linux/mod_devicetable.h>
-#include <linux/spi/spi.h>
-#include <linux/spi/spi-mem.h>
-#include <linux/gpio/consumer.h>
-#include <linux/pm_runtime.h>
+#include <linux/percpu.h>
+#include <linux/platform_data/x86/apple.h>
 #include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
 #include <linux/property.h>
-#include <linux/export.h>
+#include <linux/ptp_clock_kernel.h>
 #include <linux/sched/rt.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
 #include <uapi/linux/sched/types.h>
-#include <linux/delay.h>
-#include <linux/kthread.h>
-#include <linux/ioport.h>
-#include <linux/acpi.h>
-#include <linux/highmem.h>
-#include <linux/idr.h>
-#include <linux/platform_data/x86/apple.h>
-#include <linux/ptp_clock_kernel.h>
-#include <linux/percpu.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/spi.h>
@@ -64,7 +64,7 @@ modalias_show(struct device *dev, struct device_attribute *a, char *buf)
 	if (len != -ENODEV)
 		return len;
 
-	return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias);
+	return sysfs_emit(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias);
 }
 static DEVICE_ATTR_RO(modalias);
 
@@ -89,7 +89,7 @@ static ssize_t driver_override_show(struct device *dev,
 	ssize_t len;
 
 	device_lock(dev);
-	len = snprintf(buf, PAGE_SIZE, "%s\n", spi->driver_override ? : "");
+	len = sysfs_emit(buf, "%s\n", spi->driver_override ? : "");
 	device_unlock(dev);
 	return len;
 }
@@ -682,7 +682,7 @@ static int __spi_add_device(struct spi_device *spi)
  * @spi: spi_device to register
  *
  * Companion function to spi_alloc_device.  Devices allocated with
- * spi_alloc_device can be added onto the spi bus with this function.
+ * spi_alloc_device can be added onto the SPI bus with this function.
  *
  * Return: 0 on success; negative errno on failure
  */
@@ -889,7 +889,7 @@ int spi_register_board_info(struct spi_board_info const *info, unsigned n)
  * spi_res_alloc - allocate a spi resource that is life-cycle managed
  *                 during the processing of a spi_message while using
  *                 spi_transfer_one
- * @spi:     the spi device for which we allocate memory
+ * @spi:     the SPI device for which we allocate memory
  * @release: the release code to execute for this resource
  * @size:    size to alloc and return
  * @gfp:     GFP allocation flags
@@ -915,7 +915,7 @@ static void *spi_res_alloc(struct spi_device *spi, spi_res_release_t release,
 }
 
 /**
- * spi_res_free - free an spi resource
+ * spi_res_free - free an SPI resource
  * @res: pointer to the custom data of a resource
  */
 static void spi_res_free(void *res)
@@ -931,7 +931,7 @@ static void spi_res_free(void *res)
 
 /**
  * spi_res_add - add a spi_res to the spi_message
- * @message: the spi message
+ * @message: the SPI message
  * @res:     the spi_resource
  */
 static void spi_res_add(struct spi_message *message, void *res)
@@ -943,7 +943,7 @@ static void spi_res_add(struct spi_message *message, void *res)
 }
 
 /**
- * spi_res_release - release all spi resources for this message
+ * spi_res_release - release all SPI resources for this message
  * @ctlr:  the @spi_controller
  * @message: the @spi_message
  */
@@ -1006,7 +1006,7 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
 				gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), activate);
 		}
 		/* Some SPI masters need both GPIO CS & slave_select */
-		if ((spi->controller->flags & SPI_MASTER_GPIO_SS) &&
+		if ((spi->controller->flags & SPI_CONTROLLER_GPIO_SS) &&
 		    spi->controller->set_cs)
 			spi->controller->set_cs(spi, !enable);
 	} else if (spi->controller->set_cs) {
@@ -1424,7 +1424,7 @@ int spi_delay_to_ns(struct spi_delay *_delay, struct spi_transfer *xfer)
 			return -EINVAL;
 		/*
 		 * If there is unknown effective speed, approximate it
-		 * by underestimating with half of the requested hz.
+		 * by underestimating with half of the requested Hz.
 		 */
 		hz = xfer->effective_speed_hz ?: xfer->speed_hz / 2;
 		if (!hz)
@@ -1739,11 +1739,11 @@ static int __spi_pump_transfer_message(struct spi_controller *ctlr,
 }
 
 /**
- * __spi_pump_messages - function which processes spi message queue
+ * __spi_pump_messages - function which processes SPI message queue
  * @ctlr: controller to process queue for
  * @in_kthread: true if we are in the context of the message pump thread
  *
- * This function checks if there is any spi message in the queue that
+ * This function checks if there is any SPI message in the queue that
  * needs processing and if so call out to the driver to initialize hardware
  * and transfer each message.
  *
@@ -1758,7 +1758,7 @@ static void __spi_pump_messages(struct spi_controller *ctlr, bool in_kthread)
 	unsigned long flags;
 	int ret;
 
-	/* Take the IO mutex */
+	/* Take the I/O mutex */
 	mutex_lock(&ctlr->io_mutex);
 
 	/* Lock queue */
@@ -2169,8 +2169,8 @@ static int __spi_queued_transfer(struct spi_device *spi,
 
 /**
  * spi_queued_transfer - transfer function for queued transfers
- * @spi: spi device which is requesting transfer
- * @msg: spi message which is to handled is queued to driver queue
+ * @spi: SPI device which is requesting transfer
+ * @msg: SPI message which is to handled is queued to driver queue
  *
  * Return: zero on success, else a negative error code.
  */
@@ -2399,9 +2399,6 @@ static void of_register_spi_devices(struct spi_controller *ctlr)
 	struct spi_device *spi;
 	struct device_node *nc;
 
-	if (!ctlr->dev.of_node)
-		return;
-
 	for_each_available_child_of_node(ctlr->dev.of_node, nc) {
 		if (of_node_test_and_set_flag(nc, OF_POPULATED))
 			continue;
@@ -2499,7 +2496,7 @@ static int acpi_spi_count(struct acpi_resource *ares, void *data)
  * acpi_spi_count_resources - Count the number of SpiSerialBus resources
  * @adev:	ACPI device
  *
- * Returns the number of SpiSerialBus resources in the ACPI-device's
+ * Return: the number of SpiSerialBus resources in the ACPI-device's
  * resource-list; or a negative error code.
  */
 int acpi_spi_count_resources(struct acpi_device *adev)
@@ -2633,10 +2630,10 @@ static int acpi_spi_add_resource(struct acpi_resource *ares, void *data)
  * @adev: ACPI Device for the spi device
  * @index: Index of the spi resource inside the ACPI Node
  *
- * This should be used to allocate a new spi device from and ACPI Node.
- * The caller is responsible for calling spi_add_device to register the spi device.
+ * This should be used to allocate a new SPI device from and ACPI Device node.
+ * The caller is responsible for calling spi_add_device to register the SPI device.
  *
- * If ctlr is set to NULL, the Controller for the spi device will be looked up
+ * If ctlr is set to NULL, the Controller for the SPI device will be looked up
  * using the resource.
  * If index is set to -1, index is not used.
  * Note: If index is -1, ctlr must be set.
@@ -2817,8 +2814,7 @@ static ssize_t slave_show(struct device *dev, struct device_attribute *attr,
 	struct device *child;
 
 	child = device_find_any_child(&ctlr->dev);
-	return sprintf(buf, "%s\n",
-		       child ? to_spi_device(child)->modalias : NULL);
+	return sysfs_emit(buf, "%s\n", child ? to_spi_device(child)->modalias : NULL);
 }
 
 static ssize_t slave_store(struct device *dev, struct device_attribute *attr,
@@ -3056,7 +3052,7 @@ static int spi_get_gpio_descs(struct spi_controller *ctlr)
 
 	ctlr->unused_native_cs = ffs(~native_cs_mask) - 1;
 
-	if ((ctlr->flags & SPI_MASTER_GPIO_SS) && num_cs_gpios &&
+	if ((ctlr->flags & SPI_CONTROLLER_GPIO_SS) && num_cs_gpios &&
 	    ctlr->max_native_cs && ctlr->unused_native_cs >= ctlr->max_native_cs) {
 		dev_err(dev, "No unused native chip select available\n");
 		return -EINVAL;
@@ -3084,6 +3080,20 @@ static int spi_controller_check_ops(struct spi_controller *ctlr)
 	return 0;
 }
 
+/* Allocate dynamic bus number using Linux idr */
+static int spi_controller_id_alloc(struct spi_controller *ctlr, int start, int end)
+{
+	int id;
+
+	mutex_lock(&board_lock);
+	id = idr_alloc(&spi_master_idr, ctlr, start, end, GFP_KERNEL);
+	mutex_unlock(&board_lock);
+	if (WARN(id < 0, "couldn't get idr"))
+		return id == -ENOSPC ? -EBUSY : id;
+	ctlr->bus_num = id;
+	return 0;
+}
+
 /**
  * spi_register_controller - register SPI master or slave controller
  * @ctlr: initialized master, originally from spi_alloc_master() or
@@ -3111,8 +3121,8 @@ int spi_register_controller(struct spi_controller *ctlr)
 {
 	struct device		*dev = ctlr->dev.parent;
 	struct boardinfo	*bi;
+	int			first_dynamic;
 	int			status;
-	int			id, first_dynamic;
 
 	if (!dev)
 		return -ENODEV;
@@ -3125,27 +3135,13 @@ int spi_register_controller(struct spi_controller *ctlr)
 	if (status)
 		return status;
 
+	if (ctlr->bus_num < 0)
+		ctlr->bus_num = of_alias_get_id(ctlr->dev.of_node, "spi");
 	if (ctlr->bus_num >= 0) {
 		/* Devices with a fixed bus num must check-in with the num */
-		mutex_lock(&board_lock);
-		id = idr_alloc(&spi_master_idr, ctlr, ctlr->bus_num,
-			ctlr->bus_num + 1, GFP_KERNEL);
-		mutex_unlock(&board_lock);
-		if (WARN(id < 0, "couldn't get idr"))
-			return id == -ENOSPC ? -EBUSY : id;
-		ctlr->bus_num = id;
-	} else if (ctlr->dev.of_node) {
-		/* Allocate dynamic bus number using Linux idr */
-		id = of_alias_get_id(ctlr->dev.of_node, "spi");
-		if (id >= 0) {
-			ctlr->bus_num = id;
-			mutex_lock(&board_lock);
-			id = idr_alloc(&spi_master_idr, ctlr, ctlr->bus_num,
-				       ctlr->bus_num + 1, GFP_KERNEL);
-			mutex_unlock(&board_lock);
-			if (WARN(id < 0, "couldn't get idr"))
-				return id == -ENOSPC ? -EBUSY : id;
-		}
+		status = spi_controller_id_alloc(ctlr, ctlr->bus_num, ctlr->bus_num + 1);
+		if (status)
+			return status;
 	}
 	if (ctlr->bus_num < 0) {
 		first_dynamic = of_alias_get_highest_id("spi");
@@ -3154,13 +3150,9 @@ int spi_register_controller(struct spi_controller *ctlr)
 		else
 			first_dynamic++;
 
-		mutex_lock(&board_lock);
-		id = idr_alloc(&spi_master_idr, ctlr, first_dynamic,
-			       0, GFP_KERNEL);
-		mutex_unlock(&board_lock);
-		if (WARN(id < 0, "couldn't get idr"))
-			return id;
-		ctlr->bus_num = id;
+		status = spi_controller_id_alloc(ctlr, first_dynamic, 0);
+		if (status)
+			return status;
 	}
 	ctlr->bus_lock_flag = 0;
 	init_completion(&ctlr->xfer_completion);
@@ -3339,7 +3331,8 @@ void spi_unregister_controller(struct spi_controller *ctlr)
 	if (IS_ENABLED(CONFIG_SPI_DYNAMIC))
 		mutex_unlock(&ctlr->add_lock);
 
-	/* Release the last reference on the controller if its driver
+	/*
+	 * Release the last reference on the controller if its driver
 	 * has not yet been converted to devm_spi_alloc_master/slave().
 	 */
 	if (!ctlr->devm_allocated)
@@ -3552,7 +3545,7 @@ static int __spi_split_transfer_maxsize(struct spi_controller *ctlr,
 
 	/* All the others need rx_buf/tx_buf also set */
 	for (i = 1, offset = maxsize; i < count; offset += maxsize, i++) {
-		/* Update rx_buf, tx_buf and dma */
+		/* Update rx_buf, tx_buf and DMA */
 		if (xfers[i].rx_buf)
 			xfers[i].rx_buf += offset;
 		if (xfers[i].rx_dma)
@@ -3622,7 +3615,7 @@ EXPORT_SYMBOL_GPL(spi_split_transfers_maxsize);
 
 
 /**
- * spi_split_transfers_maxwords - split spi transfers into multiple transfers
+ * spi_split_transfers_maxwords - split SPI transfers into multiple transfers
  *                                when an individual transfer exceeds a
  *                                certain number of SPI words
  * @ctlr:     the @spi_controller for this transfer
@@ -3650,13 +3643,7 @@ int spi_split_transfers_maxwords(struct spi_controller *ctlr,
 		size_t maxsize;
 		int ret;
 
-		if (xfer->bits_per_word <= 8)
-			maxsize = maxwords;
-		else if (xfer->bits_per_word <= 16)
-			maxsize = 2 * maxwords;
-		else
-			maxsize = 4 * maxwords;
-
+		maxsize = maxwords * roundup_pow_of_two(BITS_TO_BYTES(xfer->bits_per_word));
 		if (xfer->len > maxsize) {
 			ret = __spi_split_transfer_maxsize(ctlr, msg, &xfer,
 							   maxsize, gfp);
@@ -3671,7 +3658,8 @@ EXPORT_SYMBOL_GPL(spi_split_transfers_maxwords);
 
 /*-------------------------------------------------------------------------*/
 
-/* Core methods for SPI controller protocol drivers.  Some of the
+/*
+ * Core methods for SPI controller protocol drivers. Some of the
  * other core methods are currently defined as inline functions.
  */
 
@@ -3731,7 +3719,7 @@ static int spi_set_cs_timing(struct spi_device *spi)
  * changes those settings, and must be called from a context that can sleep.
  * Except for SPI_CS_HIGH, which takes effect immediately, the changes take
  * effect the next time the device is selected and data is transferred to
- * or from it.  When this function returns, the spi device is deselected.
+ * or from it.  When this function returns, the SPI device is deselected.
  *
  * Note that this call will fail if the protocol driver specifies an option
  * that the underlying controller or its driver does not support.  For
@@ -4071,7 +4059,7 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message)
  * spi_async - asynchronous SPI transfer
  * @spi: device with which data will be exchanged
  * @message: describes the data transfers, including completion callback
- * Context: any (irqs may be blocked, etc)
+ * Context: any (IRQs may be blocked, etc)
  *
  * This call may be used in_irq and other contexts which can't sleep,
  * as well as from task contexts which can sleep.
@@ -4125,7 +4113,7 @@ EXPORT_SYMBOL_GPL(spi_async);
  * spi_async_locked - version of spi_async with exclusive bus usage
  * @spi: device with which data will be exchanged
  * @message: describes the data transfers, including completion callback
- * Context: any (irqs may be blocked, etc)
+ * Context: any (IRQs may be blocked, etc)
  *
  * This call may be used in_irq and other contexts which can't sleep,
  * as well as from task contexts which can sleep.
@@ -4388,9 +4376,9 @@ static u8	*buf;
 /**
  * spi_write_then_read - SPI synchronous write followed by read
  * @spi: device with which data will be exchanged
- * @txbuf: data to be written (need not be dma-safe)
+ * @txbuf: data to be written (need not be DMA-safe)
  * @n_tx: size of txbuf, in bytes
- * @rxbuf: buffer into which data will be read (need not be dma-safe)
+ * @rxbuf: buffer into which data will be read (need not be DMA-safe)
  * @n_rx: size of rxbuf, in bytes
  * Context: can sleep
  *
@@ -4401,7 +4389,7 @@ static u8	*buf;
  *
  * Parameters to this routine are always copied using a small buffer.
  * Performance-sensitive or bulk transfer code should instead use
- * spi_{async,sync}() calls with dma-safe buffers.
+ * spi_{async,sync}() calls with DMA-safe buffers.
  *
  * Return: zero on success, else a negative error code.
  */
@@ -4446,7 +4434,7 @@ int spi_write_then_read(struct spi_device *spi,
 	x[0].tx_buf = local_buf;
 	x[1].rx_buf = local_buf + n_tx;
 
-	/* Do the i/o */
+	/* Do the I/O */
 	status = spi_sync(spi, &message);
 	if (status == 0)
 		memcpy(rxbuf, x[1].rx_buf, n_rx);