[PATCH v3 0/4] spi: stm32: add spi device mode

[PATCH v3 0/4] spi: stm32: add spi device mode

[Valentin Caron]

STM32 SPI can operate in device mode.
This series adds this functionnality in spi-stm32 driver.

Since v2:
 - Rename this series: spi device mode

Since v1:
 - Do not add #address-cells and #size-cells in st,stm32-spi.yaml
 - Do not add cs-gpio description in st,stm32-spi.yaml
 - Do not add st,spi-slave-underrun property to handle spi slave underrun

Alain Volmat (3):
  spi: stm32: renaming of spi_master into spi_controller
  spi: stm32: use dmaengine_terminate_{a}sync instead of _all
  dt-bindings: spi: stm32: disable spi-slave property for stm32f4-f7

Valentin Caron (1):
  spi: stm32: introduction of stm32h7 SPI device mode support

 .../devicetree/bindings/spi/st,stm32-spi.yaml |   1 +
 drivers/spi/Kconfig                           |   1 +
 drivers/spi/spi-stm32.c                       | 274 ++++++++++--------
 3 files changed, 161 insertions(+), 115 deletions(-)

-- 
2.25.1

[PATCH v3 1/4] spi: stm32: renaming of spi_master into spi_controller

[Valentin Caron]

From: Alain Volmat <alain.volmat@foss.st.com>

Preparing introduction of SPI device, rename the spi_master structure
into spi_controller. This doesn't have any functional impact since
spi_master was already a macro for spi_controller.
Referring now to ctrl instead of master since the spi_controller
structure might not be used as a master controller only.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
---
 drivers/spi/spi-stm32.c | 154 ++++++++++++++++++++--------------------
 1 file changed, 77 insertions(+), 77 deletions(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index d6598e4116bd..5d9439ae1c09 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 //
-// STMicroelectronics STM32 SPI Controller driver (master mode only)
+// STMicroelectronics STM32 SPI Controller driver
 //
 // Copyright (C) 2017, STMicroelectronics - All Rights Reserved
 // Author(s): Amelie Delaunay <amelie.delaunay@st.com> for STMicroelectronics.
@@ -258,7 +258,7 @@ struct stm32_spi_cfg {
 /**
  * struct stm32_spi - private data of the SPI controller
  * @dev: driver model representation of the controller
- * @master: controller master interface
+ * @ctrl: controller interface
  * @cfg: compatible configuration data
  * @base: virtual memory area
  * @clk: hw kernel clock feeding the SPI clock generator
@@ -283,7 +283,7 @@ struct stm32_spi_cfg {
  */
 struct stm32_spi {
 	struct device *dev;
-	struct spi_master *master;
+	struct spi_controller *ctrl;
 	const struct stm32_spi_cfg *cfg;
 	void __iomem *base;
 	struct clk *clk;
@@ -437,9 +437,9 @@ static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz,
 	div = DIV_ROUND_CLOSEST(spi->clk_rate & ~0x1, speed_hz);
 
 	/*
-	 * SPI framework set xfer->speed_hz to master->max_speed_hz if
-	 * xfer->speed_hz is greater than master->max_speed_hz, and it returns
-	 * an error when xfer->speed_hz is lower than master->min_speed_hz, so
+	 * SPI framework set xfer->speed_hz to ctrl->max_speed_hz if
+	 * xfer->speed_hz is greater than ctrl->max_speed_hz, and it returns
+	 * an error when xfer->speed_hz is lower than ctrl->min_speed_hz, so
 	 * no need to check it there.
 	 * However, we need to ensure the following calculations.
 	 */
@@ -714,19 +714,19 @@ static void stm32h7_spi_disable(struct stm32_spi *spi)
 
 /**
  * stm32_spi_can_dma - Determine if the transfer is eligible for DMA use
- * @master: controller master interface
+ * @ctrl: controller interface
  * @spi_dev: pointer to the spi device
  * @transfer: pointer to spi transfer
  *
  * If driver has fifo and the current transfer size is greater than fifo size,
  * use DMA. Otherwise use DMA for transfer longer than defined DMA min bytes.
  */
-static bool stm32_spi_can_dma(struct spi_master *master,
+static bool stm32_spi_can_dma(struct spi_controller *ctrl,
 			      struct spi_device *spi_dev,
 			      struct spi_transfer *transfer)
 {
 	unsigned int dma_size;
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 
 	if (spi->cfg->has_fifo)
 		dma_size = spi->fifo_size;
@@ -742,12 +742,12 @@ static bool stm32_spi_can_dma(struct spi_master *master,
 /**
  * stm32f4_spi_irq_event - Interrupt handler for SPI controller events
  * @irq: interrupt line
- * @dev_id: SPI controller master interface
+ * @dev_id: SPI controller ctrl interface
  */
 static irqreturn_t stm32f4_spi_irq_event(int irq, void *dev_id)
 {
-	struct spi_master *master = dev_id;
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct spi_controller *ctrl = dev_id;
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 	u32 sr, mask = 0;
 	bool end = false;
 
@@ -830,14 +830,14 @@ static irqreturn_t stm32f4_spi_irq_event(int irq, void *dev_id)
 /**
  * stm32f4_spi_irq_thread - Thread of interrupt handler for SPI controller
  * @irq: interrupt line
- * @dev_id: SPI controller master interface
+ * @dev_id: SPI controller interface
  */
 static irqreturn_t stm32f4_spi_irq_thread(int irq, void *dev_id)
 {
-	struct spi_master *master = dev_id;
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct spi_controller *ctrl = dev_id;
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 
-	spi_finalize_current_transfer(master);
+	spi_finalize_current_transfer(ctrl);
 	stm32f4_spi_disable(spi);
 
 	return IRQ_HANDLED;
@@ -846,12 +846,12 @@ static irqreturn_t stm32f4_spi_irq_thread(int irq, void *dev_id)
 /**
  * stm32h7_spi_irq_thread - Thread of interrupt handler for SPI controller
  * @irq: interrupt line
- * @dev_id: SPI controller master interface
+ * @dev_id: SPI controller interface
  */
 static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
 {
-	struct spi_master *master = dev_id;
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct spi_controller *ctrl = dev_id;
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 	u32 sr, ier, mask;
 	unsigned long flags;
 	bool end = false;
@@ -931,7 +931,7 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
 
 	if (end) {
 		stm32h7_spi_disable(spi);
-		spi_finalize_current_transfer(master);
+		spi_finalize_current_transfer(ctrl);
 	}
 
 	return IRQ_HANDLED;
@@ -939,13 +939,13 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
 
 /**
  * stm32_spi_prepare_msg - set up the controller to transfer a single message
- * @master: controller master interface
+ * @ctrl: controller interface
  * @msg: pointer to spi message
  */
-static int stm32_spi_prepare_msg(struct spi_master *master,
+static int stm32_spi_prepare_msg(struct spi_controller *ctrl,
 				 struct spi_message *msg)
 {
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 	struct spi_device *spi_dev = msg->spi;
 	struct device_node *np = spi_dev->dev.of_node;
 	unsigned long flags;
@@ -984,9 +984,9 @@ static int stm32_spi_prepare_msg(struct spi_master *master,
 	if (spi->cfg->set_number_of_data) {
 		int ret;
 
-		ret = spi_split_transfers_maxwords(master, msg,
-						   STM32H7_SPI_TSIZE_MAX,
-						   GFP_KERNEL | GFP_DMA);
+		ret = spi_split_transfers_maxsize(ctrl, msg,
+						  STM32H7_SPI_TSIZE_MAX,
+						  GFP_KERNEL | GFP_DMA);
 		if (ret)
 			return ret;
 	}
@@ -1016,7 +1016,7 @@ static void stm32f4_spi_dma_tx_cb(void *data)
 	struct stm32_spi *spi = data;
 
 	if (spi->cur_comm == SPI_SIMPLEX_TX || spi->cur_comm == SPI_3WIRE_TX) {
-		spi_finalize_current_transfer(spi->master);
+		spi_finalize_current_transfer(spi->ctrl);
 		stm32f4_spi_disable(spi);
 	}
 }
@@ -1031,7 +1031,7 @@ static void stm32_spi_dma_rx_cb(void *data)
 {
 	struct stm32_spi *spi = data;
 
-	spi_finalize_current_transfer(spi->master);
+	spi_finalize_current_transfer(spi->ctrl);
 	spi->cfg->disable(spi);
 }
 
@@ -1589,18 +1589,18 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
 
 /**
  * stm32_spi_transfer_one - transfer a single spi_transfer
- * @master: controller master interface
+ * @ctrl: controller interface
  * @spi_dev: pointer to the spi device
  * @transfer: pointer to spi transfer
  *
  * It must return 0 if the transfer is finished or 1 if the transfer is still
  * in progress.
  */
-static int stm32_spi_transfer_one(struct spi_master *master,
+static int stm32_spi_transfer_one(struct spi_controller *ctrl,
 				  struct spi_device *spi_dev,
 				  struct spi_transfer *transfer)
 {
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 	int ret;
 
 	spi->tx_buf = transfer->tx_buf;
@@ -1608,8 +1608,8 @@ static int stm32_spi_transfer_one(struct spi_master *master,
 	spi->tx_len = spi->tx_buf ? transfer->len : 0;
 	spi->rx_len = spi->rx_buf ? transfer->len : 0;
 
-	spi->cur_usedma = (master->can_dma &&
-			   master->can_dma(master, spi_dev, transfer));
+	spi->cur_usedma = (ctrl->can_dma &&
+			   ctrl->can_dma(ctrl, spi_dev, transfer));
 
 	ret = stm32_spi_transfer_one_setup(spi, spi_dev, transfer);
 	if (ret) {
@@ -1625,13 +1625,13 @@ static int stm32_spi_transfer_one(struct spi_master *master,
 
 /**
  * stm32_spi_unprepare_msg - relax the hardware
- * @master: controller master interface
+ * @ctrl: controller interface
  * @msg: pointer to the spi message
  */
-static int stm32_spi_unprepare_msg(struct spi_master *master,
+static int stm32_spi_unprepare_msg(struct spi_controller *ctrl,
 				   struct spi_message *msg)
 {
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 
 	spi->cfg->disable(spi);
 
@@ -1758,22 +1758,22 @@ MODULE_DEVICE_TABLE(of, stm32_spi_of_match);
 
 static int stm32_spi_probe(struct platform_device *pdev)
 {
-	struct spi_master *master;
+	struct spi_controller *ctrl;
 	struct stm32_spi *spi;
 	struct resource *res;
 	struct reset_control *rst;
 	int ret;
 
-	master = devm_spi_alloc_master(&pdev->dev, sizeof(struct stm32_spi));
-	if (!master) {
+	ctrl = devm_spi_alloc_master(&pdev->dev, sizeof(struct stm32_spi));
+	if (!ctrl) {
 		dev_err(&pdev->dev, "spi master allocation failed\n");
 		return -ENOMEM;
 	}
-	platform_set_drvdata(pdev, master);
+	platform_set_drvdata(pdev, ctrl);
 
-	spi = spi_master_get_devdata(master);
+	spi = spi_controller_get_devdata(ctrl);
 	spi->dev = &pdev->dev;
-	spi->master = master;
+	spi->ctrl = ctrl;
 	spin_lock_init(&spi->lock);
 
 	spi->cfg = (const struct stm32_spi_cfg *)
@@ -1794,7 +1794,7 @@ static int stm32_spi_probe(struct platform_device *pdev)
 	ret = devm_request_threaded_irq(&pdev->dev, spi->irq,
 					spi->cfg->irq_handler_event,
 					spi->cfg->irq_handler_thread,
-					IRQF_ONESHOT, pdev->name, master);
+					IRQF_ONESHOT, pdev->name, ctrl);
 	if (ret) {
 		dev_err(&pdev->dev, "irq%d request failed: %d\n", spi->irq,
 			ret);
@@ -1843,19 +1843,19 @@ static int stm32_spi_probe(struct platform_device *pdev)
 		goto err_clk_disable;
 	}
 
-	master->dev.of_node = pdev->dev.of_node;
-	master->auto_runtime_pm = true;
-	master->bus_num = pdev->id;
-	master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST |
-			    SPI_3WIRE;
-	master->bits_per_word_mask = spi->cfg->get_bpw_mask(spi);
-	master->max_speed_hz = spi->clk_rate / spi->cfg->baud_rate_div_min;
-	master->min_speed_hz = spi->clk_rate / spi->cfg->baud_rate_div_max;
-	master->use_gpio_descriptors = true;
-	master->prepare_message = stm32_spi_prepare_msg;
-	master->transfer_one = stm32_spi_transfer_one;
-	master->unprepare_message = stm32_spi_unprepare_msg;
-	master->flags = spi->cfg->flags;
+	ctrl->dev.of_node = pdev->dev.of_node;
+	ctrl->auto_runtime_pm = true;
+	ctrl->bus_num = pdev->id;
+	ctrl->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST |
+			  SPI_3WIRE;
+	ctrl->bits_per_word_mask = spi->cfg->get_bpw_mask(spi);
+	ctrl->max_speed_hz = spi->clk_rate / spi->cfg->baud_rate_div_min;
+	ctrl->min_speed_hz = spi->clk_rate / spi->cfg->baud_rate_div_max;
+	ctrl->use_gpio_descriptors = true;
+	ctrl->prepare_message = stm32_spi_prepare_msg;
+	ctrl->transfer_one = stm32_spi_transfer_one;
+	ctrl->unprepare_message = stm32_spi_unprepare_msg;
+	ctrl->flags = spi->cfg->flags;
 
 	spi->dma_tx = dma_request_chan(spi->dev, "tx");
 	if (IS_ERR(spi->dma_tx)) {
@@ -1866,7 +1866,7 @@ static int stm32_spi_probe(struct platform_device *pdev)
 
 		dev_warn(&pdev->dev, "failed to request tx dma channel\n");
 	} else {
-		master->dma_tx = spi->dma_tx;
+		ctrl->dma_tx = spi->dma_tx;
 	}
 
 	spi->dma_rx = dma_request_chan(spi->dev, "rx");
@@ -1878,11 +1878,11 @@ static int stm32_spi_probe(struct platform_device *pdev)
 
 		dev_warn(&pdev->dev, "failed to request rx dma channel\n");
 	} else {
-		master->dma_rx = spi->dma_rx;
+		ctrl->dma_rx = spi->dma_rx;
 	}
 
 	if (spi->dma_tx || spi->dma_rx)
-		master->can_dma = stm32_spi_can_dma;
+		ctrl->can_dma = stm32_spi_can_dma;
 
 	pm_runtime_set_autosuspend_delay(&pdev->dev,
 					 STM32_SPI_AUTOSUSPEND_DELAY);
@@ -1891,9 +1891,9 @@ static int stm32_spi_probe(struct platform_device *pdev)
 	pm_runtime_get_noresume(&pdev->dev);
 	pm_runtime_enable(&pdev->dev);
 
-	ret = spi_register_master(master);
+	ret = spi_register_controller(ctrl);
 	if (ret) {
-		dev_err(&pdev->dev, "spi master registration failed: %d\n",
+		dev_err(&pdev->dev, "spi controller registration failed: %d\n",
 			ret);
 		goto err_pm_disable;
 	}
@@ -1923,12 +1923,12 @@ static int stm32_spi_probe(struct platform_device *pdev)
 
 static void stm32_spi_remove(struct platform_device *pdev)
 {
-	struct spi_master *master = platform_get_drvdata(pdev);
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct spi_controller *ctrl = platform_get_drvdata(pdev);
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 
 	pm_runtime_get_sync(&pdev->dev);
 
-	spi_unregister_master(master);
+	spi_unregister_controller(ctrl);
 	spi->cfg->disable(spi);
 
 	pm_runtime_disable(&pdev->dev);
@@ -1936,10 +1936,10 @@ static void stm32_spi_remove(struct platform_device *pdev)
 	pm_runtime_set_suspended(&pdev->dev);
 	pm_runtime_dont_use_autosuspend(&pdev->dev);
 
-	if (master->dma_tx)
-		dma_release_channel(master->dma_tx);
-	if (master->dma_rx)
-		dma_release_channel(master->dma_rx);
+	if (ctrl->dma_tx)
+		dma_release_channel(ctrl->dma_tx);
+	if (ctrl->dma_rx)
+		dma_release_channel(ctrl->dma_rx);
 
 	clk_disable_unprepare(spi->clk);
 
@@ -1949,8 +1949,8 @@ static void stm32_spi_remove(struct platform_device *pdev)
 
 static int __maybe_unused stm32_spi_runtime_suspend(struct device *dev)
 {
-	struct spi_master *master = dev_get_drvdata(dev);
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct spi_controller *ctrl = dev_get_drvdata(dev);
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 
 	clk_disable_unprepare(spi->clk);
 
@@ -1959,8 +1959,8 @@ static int __maybe_unused stm32_spi_runtime_suspend(struct device *dev)
 
 static int __maybe_unused stm32_spi_runtime_resume(struct device *dev)
 {
-	struct spi_master *master = dev_get_drvdata(dev);
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct spi_controller *ctrl = dev_get_drvdata(dev);
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 	int ret;
 
 	ret = pinctrl_pm_select_default_state(dev);
@@ -1972,10 +1972,10 @@ static int __maybe_unused stm32_spi_runtime_resume(struct device *dev)
 
 static int __maybe_unused stm32_spi_suspend(struct device *dev)
 {
-	struct spi_master *master = dev_get_drvdata(dev);
+	struct spi_controller *ctrl = dev_get_drvdata(dev);
 	int ret;
 
-	ret = spi_master_suspend(master);
+	ret = spi_controller_suspend(ctrl);
 	if (ret)
 		return ret;
 
@@ -1984,15 +1984,15 @@ static int __maybe_unused stm32_spi_suspend(struct device *dev)
 
 static int __maybe_unused stm32_spi_resume(struct device *dev)
 {
-	struct spi_master *master = dev_get_drvdata(dev);
-	struct stm32_spi *spi = spi_master_get_devdata(master);
+	struct spi_controller *ctrl = dev_get_drvdata(dev);
+	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
 	int ret;
 
 	ret = pm_runtime_force_resume(dev);
 	if (ret)
 		return ret;
 
-	ret = spi_master_resume(master);
+	ret = spi_controller_resume(ctrl);
 	if (ret) {
 		clk_disable_unprepare(spi->clk);
 		return ret;
-- 
2.25.1

[PATCH v3 2/4] spi: stm32: use dmaengine_terminate_{a}sync instead of _all

[Valentin Caron]

From: Alain Volmat <alain.volmat@foss.st.com>

Avoid usage of deprecated dmaengine_terminate_all and use
dmaengine_terminate_sync and dmaengine_terminate_async instead.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
---
 drivers/spi/spi-stm32.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index 5d9439ae1c09..82fbd20e8a96 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -657,9 +657,9 @@ static void stm32f4_spi_disable(struct stm32_spi *spi)
 	}
 
 	if (spi->cur_usedma && spi->dma_tx)
-		dmaengine_terminate_all(spi->dma_tx);
+		dmaengine_terminate_async(spi->dma_tx);
 	if (spi->cur_usedma && spi->dma_rx)
-		dmaengine_terminate_all(spi->dma_rx);
+		dmaengine_terminate_async(spi->dma_rx);
 
 	stm32_spi_clr_bits(spi, STM32F4_SPI_CR1, STM32F4_SPI_CR1_SPE);
 
@@ -696,9 +696,9 @@ static void stm32h7_spi_disable(struct stm32_spi *spi)
 	}
 
 	if (spi->cur_usedma && spi->dma_tx)
-		dmaengine_terminate_all(spi->dma_tx);
+		dmaengine_terminate_async(spi->dma_tx);
 	if (spi->cur_usedma && spi->dma_rx)
-		dmaengine_terminate_all(spi->dma_rx);
+		dmaengine_terminate_async(spi->dma_rx);
 
 	stm32_spi_clr_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_SPE);
 
@@ -1302,7 +1302,7 @@ static int stm32_spi_transfer_one_dma(struct stm32_spi *spi,
 
 dma_submit_error:
 	if (spi->dma_rx)
-		dmaengine_terminate_all(spi->dma_rx);
+		dmaengine_terminate_sync(spi->dma_rx);
 
 dma_desc_error:
 	stm32_spi_clr_bits(spi, spi->cfg->regs->dma_rx_en.reg,
-- 
2.25.1

[PATCH v3 3/4] dt-bindings: spi: stm32: disable spi-slave property for stm32f4-f7

[Valentin Caron]

From: Alain Volmat <alain.volmat@foss.st.com>

STM32F4 and STM32F7 can't switch to spi device mode.
Forbid this property with compatible "st,stm32f4-spi".

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
---
 Documentation/devicetree/bindings/spi/st,stm32-spi.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/spi/st,stm32-spi.yaml b/Documentation/devicetree/bindings/spi/st,stm32-spi.yaml
index 9ca1a843c820..f1c86e694af1 100644
--- a/Documentation/devicetree/bindings/spi/st,stm32-spi.yaml
+++ b/Documentation/devicetree/bindings/spi/st,stm32-spi.yaml
@@ -27,6 +27,7 @@ allOf:
     then:
       properties:
         st,spi-midi-ns: false
+        spi-slave: false
 
 properties:
   compatible:
-- 
2.25.1

[PATCH v3 4/4] spi: stm32: introduction of stm32h7 SPI device mode support

[Valentin Caron]

Add support for stm32h7 to use SPI controller in device role.
In such case, the spi instance should have the spi-slave property
defined.

Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
---
 drivers/spi/Kconfig     |   1 +
 drivers/spi/spi-stm32.c | 112 ++++++++++++++++++++++++++++------------
 2 files changed, 79 insertions(+), 34 deletions(-)

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 3de2ebe8294a..14810d24733b 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -936,6 +936,7 @@ config SPI_SPRD_ADI
 config SPI_STM32
 	tristate "STMicroelectronics STM32 SPI controller"
 	depends on ARCH_STM32 || COMPILE_TEST
+	select SPI_SLAVE
 	help
 	  SPI driver for STMicroelectronics STM32 SoCs.
 
diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index 82fbd20e8a96..6d10fa4ab783 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -117,6 +117,7 @@
 #define STM32H7_SPI_CFG2_CPHA		BIT(24)
 #define STM32H7_SPI_CFG2_CPOL		BIT(25)
 #define STM32H7_SPI_CFG2_SSM		BIT(26)
+#define STM32H7_SPI_CFG2_SSIOP		BIT(28)
 #define STM32H7_SPI_CFG2_AFCNTR		BIT(31)
 
 /* STM32H7_SPI_IER bit fields */
@@ -170,6 +171,10 @@
  */
 #define SPI_DMA_MIN_BYTES	16
 
+/* STM32 SPI driver helpers */
+#define STM32_SPI_MASTER_MODE(stm32_spi) (!(stm32_spi)->device_mode)
+#define STM32_SPI_DEVICE_MODE(stm32_spi) ((stm32_spi)->device_mode)
+
 /**
  * struct stm32_spi_reg - stm32 SPI register & bitfield desc
  * @reg:		register offset
@@ -190,6 +195,7 @@ struct stm32_spi_reg {
  * @cpol: clock polarity register and polarity bit
  * @cpha: clock phase register and phase bit
  * @lsb_first: LSB transmitted first register and bit
+ * @cs_high: chips select active value
  * @br: baud rate register and bitfields
  * @rx: SPI RX data register
  * @tx: SPI TX data register
@@ -201,6 +207,7 @@ struct stm32_spi_regspec {
 	const struct stm32_spi_reg cpol;
 	const struct stm32_spi_reg cpha;
 	const struct stm32_spi_reg lsb_first;
+	const struct stm32_spi_reg cs_high;
 	const struct stm32_spi_reg br;
 	const struct stm32_spi_reg rx;
 	const struct stm32_spi_reg tx;
@@ -280,6 +287,7 @@ struct stm32_spi_cfg {
  * @dma_tx: dma channel for TX transfer
  * @dma_rx: dma channel for RX transfer
  * @phys_addr: SPI registers physical base address
+ * @device_mode: the controller is configured as SPI device
  */
 struct stm32_spi {
 	struct device *dev;
@@ -307,6 +315,8 @@ struct stm32_spi {
 	struct dma_chan *dma_tx;
 	struct dma_chan *dma_rx;
 	dma_addr_t phys_addr;
+
+	bool device_mode;
 };
 
 static const struct stm32_spi_regspec stm32f4_spi_regspec = {
@@ -318,6 +328,7 @@ static const struct stm32_spi_regspec stm32f4_spi_regspec = {
 	.cpol = { STM32F4_SPI_CR1, STM32F4_SPI_CR1_CPOL },
 	.cpha = { STM32F4_SPI_CR1, STM32F4_SPI_CR1_CPHA },
 	.lsb_first = { STM32F4_SPI_CR1, STM32F4_SPI_CR1_LSBFRST },
+	.cs_high = {},
 	.br = { STM32F4_SPI_CR1, STM32F4_SPI_CR1_BR, STM32F4_SPI_CR1_BR_SHIFT },
 
 	.rx = { STM32F4_SPI_DR },
@@ -336,6 +347,7 @@ static const struct stm32_spi_regspec stm32h7_spi_regspec = {
 	.cpol = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_CPOL },
 	.cpha = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_CPHA },
 	.lsb_first = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_LSBFRST },
+	.cs_high = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_SSIOP },
 	.br = { STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_MBR,
 		STM32H7_SPI_CFG1_MBR_SHIFT },
 
@@ -971,6 +983,11 @@ static int stm32_spi_prepare_msg(struct spi_controller *ctrl,
 	else
 		clrb |= spi->cfg->regs->lsb_first.mask;
 
+	if (STM32_SPI_DEVICE_MODE(spi) && spi_dev->mode & SPI_CS_HIGH)
+		setb |= spi->cfg->regs->cs_high.mask;
+	else
+		clrb |= spi->cfg->regs->cs_high.mask;
+
 	dev_dbg(spi->dev, "cpol=%d cpha=%d lsb_first=%d cs_high=%d\n",
 		!!(spi_dev->mode & SPI_CPOL),
 		!!(spi_dev->mode & SPI_CPHA),
@@ -1161,7 +1178,8 @@ static int stm32h7_spi_transfer_one_irq(struct stm32_spi *spi)
 	if (spi->tx_buf)
 		stm32h7_spi_write_txfifo(spi);
 
-	stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART);
+	if (STM32_SPI_MASTER_MODE(spi))
+		stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART);
 
 	writel_relaxed(ier, spi->base + STM32H7_SPI_IER);
 
@@ -1208,7 +1226,8 @@ static void stm32h7_spi_transfer_one_dma_start(struct stm32_spi *spi)
 
 	stm32_spi_enable(spi);
 
-	stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART);
+	if (STM32_SPI_MASTER_MODE(spi))
+		stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART);
 }
 
 /**
@@ -1536,16 +1555,18 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
 	spi->cfg->set_bpw(spi);
 
 	/* Update spi->cur_speed with real clock speed */
-	mbr = stm32_spi_prepare_mbr(spi, transfer->speed_hz,
-				    spi->cfg->baud_rate_div_min,
-				    spi->cfg->baud_rate_div_max);
-	if (mbr < 0) {
-		ret = mbr;
-		goto out;
-	}
+	if (STM32_SPI_MASTER_MODE(spi)) {
+		mbr = stm32_spi_prepare_mbr(spi, transfer->speed_hz,
+					    spi->cfg->baud_rate_div_min,
+					    spi->cfg->baud_rate_div_max);
+		if (mbr < 0) {
+			ret = mbr;
+			goto out;
+		}
 
-	transfer->speed_hz = spi->cur_speed;
-	stm32_spi_set_mbr(spi, mbr);
+		transfer->speed_hz = spi->cur_speed;
+		stm32_spi_set_mbr(spi, mbr);
+	}
 
 	comm_type = stm32_spi_communication_type(spi_dev, transfer);
 	ret = spi->cfg->set_mode(spi, comm_type);
@@ -1554,7 +1575,7 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
 
 	spi->cur_comm = comm_type;
 
-	if (spi->cfg->set_data_idleness)
+	if (STM32_SPI_MASTER_MODE(spi) && spi->cfg->set_data_idleness)
 		spi->cfg->set_data_idleness(spi, transfer->len);
 
 	if (spi->cur_bpw <= 8)
@@ -1575,7 +1596,8 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
 	dev_dbg(spi->dev,
 		"data frame of %d-bit, data packet of %d data frames\n",
 		spi->cur_bpw, spi->cur_fthlv);
-	dev_dbg(spi->dev, "speed set to %dHz\n", spi->cur_speed);
+	if (STM32_SPI_MASTER_MODE(spi))
+		dev_dbg(spi->dev, "speed set to %dHz\n", spi->cur_speed);
 	dev_dbg(spi->dev, "transfer of %d bytes (%d data frames)\n",
 		spi->cur_xferlen, nb_words);
 	dev_dbg(spi->dev, "dma %s\n",
@@ -1670,12 +1692,13 @@ static int stm32f4_spi_config(struct stm32_spi *spi)
 }
 
 /**
- * stm32h7_spi_config - Configure SPI controller as SPI master
+ * stm32h7_spi_config - Configure SPI controller
  * @spi: pointer to the spi controller data structure
  */
 static int stm32h7_spi_config(struct stm32_spi *spi)
 {
 	unsigned long flags;
+	u32 cr1 = 0, cfg2 = 0;
 
 	spin_lock_irqsave(&spi->lock, flags);
 
@@ -1683,24 +1706,28 @@ static int stm32h7_spi_config(struct stm32_spi *spi)
 	stm32_spi_clr_bits(spi, STM32H7_SPI_I2SCFGR,
 			   STM32H7_SPI_I2SCFGR_I2SMOD);
 
-	/*
-	 * - SS input value high
-	 * - transmitter half duplex direction
-	 * - automatic communication suspend when RX-Fifo is full
-	 */
-	stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_SSI |
-						 STM32H7_SPI_CR1_HDDIR |
-						 STM32H7_SPI_CR1_MASRX);
+	if (STM32_SPI_DEVICE_MODE(spi)) {
+		/* Use native device select */
+		cfg2 &= ~STM32H7_SPI_CFG2_SSM;
+	} else {
+		/*
+		 * - Transmitter half duplex direction
+		 * - Automatic communication suspend when RX-Fifo is full
+		 * - SS input value high
+		 */
+		cr1 |= STM32H7_SPI_CR1_HDDIR | STM32H7_SPI_CR1_MASRX | STM32H7_SPI_CR1_SSI;
 
-	/*
-	 * - Set the master mode (default Motorola mode)
-	 * - Consider 1 master/n slaves configuration and
-	 *   SS input value is determined by the SSI bit
-	 * - keep control of all associated GPIOs
-	 */
-	stm32_spi_set_bits(spi, STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_MASTER |
-						  STM32H7_SPI_CFG2_SSM |
-						  STM32H7_SPI_CFG2_AFCNTR);
+		/*
+		 * - Set the master mode (default Motorola mode)
+		 * - Consider 1 master/n devices configuration and
+		 *   SS input value is determined by the SSI bit
+		 * - keep control of all associated GPIOs
+		 */
+		cfg2 |= STM32H7_SPI_CFG2_MASTER | STM32H7_SPI_CFG2_SSM | STM32H7_SPI_CFG2_AFCNTR;
+	}
+
+	stm32_spi_set_bits(spi, STM32H7_SPI_CR1, cr1);
+	stm32_spi_set_bits(spi, STM32H7_SPI_CFG2, cfg2);
 
 	spin_unlock_irqrestore(&spi->lock, flags);
 
@@ -1756,17 +1783,30 @@ static const struct of_device_id stm32_spi_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, stm32_spi_of_match);
 
+static int stm32h7_spi_device_abort(struct spi_controller *ctrl)
+{
+	spi_finalize_current_transfer(ctrl);
+	return 0;
+}
+
 static int stm32_spi_probe(struct platform_device *pdev)
 {
 	struct spi_controller *ctrl;
 	struct stm32_spi *spi;
 	struct resource *res;
 	struct reset_control *rst;
+	struct device_node *np = pdev->dev.of_node;
+	bool device_mode;
 	int ret;
 
-	ctrl = devm_spi_alloc_master(&pdev->dev, sizeof(struct stm32_spi));
+	device_mode = of_property_read_bool(np, "spi-slave");
+
+	if (device_mode)
+		ctrl = devm_spi_alloc_slave(&pdev->dev, sizeof(struct stm32_spi));
+	else
+		ctrl = devm_spi_alloc_master(&pdev->dev, sizeof(struct stm32_spi));
 	if (!ctrl) {
-		dev_err(&pdev->dev, "spi master allocation failed\n");
+		dev_err(&pdev->dev, "spi controller allocation failed\n");
 		return -ENOMEM;
 	}
 	platform_set_drvdata(pdev, ctrl);
@@ -1774,6 +1814,7 @@ static int stm32_spi_probe(struct platform_device *pdev)
 	spi = spi_controller_get_devdata(ctrl);
 	spi->dev = &pdev->dev;
 	spi->ctrl = ctrl;
+	spi->device_mode = device_mode;
 	spin_lock_init(&spi->lock);
 
 	spi->cfg = (const struct stm32_spi_cfg *)
@@ -1856,6 +1897,8 @@ static int stm32_spi_probe(struct platform_device *pdev)
 	ctrl->transfer_one = stm32_spi_transfer_one;
 	ctrl->unprepare_message = stm32_spi_unprepare_msg;
 	ctrl->flags = spi->cfg->flags;
+	if (STM32_SPI_DEVICE_MODE(spi))
+		ctrl->slave_abort = stm32h7_spi_device_abort;
 
 	spi->dma_tx = dma_request_chan(spi->dev, "tx");
 	if (IS_ERR(spi->dma_tx)) {
@@ -1901,7 +1944,8 @@ static int stm32_spi_probe(struct platform_device *pdev)
 	pm_runtime_mark_last_busy(&pdev->dev);
 	pm_runtime_put_autosuspend(&pdev->dev);
 
-	dev_info(&pdev->dev, "driver initialized\n");
+	dev_info(&pdev->dev, "driver initialized (%s mode)\n",
+		 STM32_SPI_MASTER_MODE(spi) ? "master" : "device");
 
 	return 0;
 
-- 
2.25.1

Re: [PATCH v3 0/4] spi: stm32: add spi device mode

[Mark Brown]

On Thu, 15 Jun 2023 09:58:11 +0200, Valentin Caron wrote:
> STM32 SPI can operate in device mode.
> This series adds this functionnality in spi-stm32 driver.
> 
> Since v2:
>  - Rename this series: spi device mode
> 
> Since v1:
>  - Do not add #address-cells and #size-cells in st,stm32-spi.yaml
>  - Do not add cs-gpio description in st,stm32-spi.yaml
>  - Do not add st,spi-slave-underrun property to handle spi slave underrun
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/4] spi: stm32: renaming of spi_master into spi_controller
      commit: 6f486556abe35f2e6684f95241acbc463342d3eb
[2/4] spi: stm32: use dmaengine_terminate_{a}sync instead of _all
      commit: 4f2b39dc2d14d4fc55d7a3a140ac07eaa761b701
[3/4] dt-bindings: spi: stm32: disable spi-slave property for stm32f4-f7
      commit: e6afe03351ac81fbc4f2b93bf3b356f7b662939d
[4/4] spi: stm32: introduction of stm32h7 SPI device mode support
      commit: e40335fcb89acb274d05deffad9225e973278ec9

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

Re: [PATCH v3 3/4] dt-bindings: spi: stm32: disable spi-slave property for stm32f4-f7

[Krzysztof Kozlowski]

On 15/06/2023 09:58, Valentin Caron wrote:
> From: Alain Volmat <alain.volmat@foss.st.com>
> 
> STM32F4 and STM32F7 can't switch to spi device mode.
> Forbid this property with compatible "st,stm32f4-spi".

Just to clarify - driver cannot switch or hardware does not support it?

Please use subject prefixes matching the subsystem. You can get them for
example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
your patch is touching. (spi: dt-bindings:)

Best regards,
Krzysztof

Re: [PATCH v3 3/4] dt-bindings: spi: stm32: disable spi-slave property for stm32f4-f7

[Valentin CARON]

Hi Krzysztof,

On 6/15/23 15:36, Krzysztof Kozlowski wrote:
> On 15/06/2023 09:58, Valentin Caron wrote:
>> From: Alain Volmat <alain.volmat@foss.st.com>
>>
>> STM32F4 and STM32F7 can't switch to spi device mode.
>> Forbid this property with compatible "st,stm32f4-spi".
> Just to clarify - driver cannot switch or hardware does not support it?

Driver can't support it right now but hardware can.

> Please use subject prefixes matching the subsystem. You can get them for
> example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
> your patch is touching. (spi: dt-bindings:)
Sorry, I missed that.
> Best regards,
> Krzysztof

Regards,
Valentin

Re: [PATCH v3 3/4] dt-bindings: spi: stm32: disable spi-slave property for stm32f4-f7

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 495 bytes --]

On Thu, Jun 15, 2023 at 07:38:36PM +0200, Valentin CARON wrote:
> On 6/15/23 15:36, Krzysztof Kozlowski wrote:
> > On 15/06/2023 09:58, Valentin Caron wrote:

> > > STM32F4 and STM32F7 can't switch to spi device mode.
> > > Forbid this property with compatible "st,stm32f4-spi".

> > Just to clarify - driver cannot switch or hardware does not support it?

> Driver can't support it right now but hardware can.

That shouldn't be a restriction in the DT then, please send a patch
dropping this.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: [PATCH v3 3/4] dt-bindings: spi: stm32: disable spi-slave property for stm32f4-f7

[Krzysztof Kozlowski]

On 15/06/2023 19:38, Valentin CARON wrote:
> Hi Krzysztof,
> 
> On 6/15/23 15:36, Krzysztof Kozlowski wrote:
>> On 15/06/2023 09:58, Valentin Caron wrote:
>>> From: Alain Volmat <alain.volmat@foss.st.com>
>>>
>>> STM32F4 and STM32F7 can't switch to spi device mode.
>>> Forbid this property with compatible "st,stm32f4-spi".
>> Just to clarify - driver cannot switch or hardware does not support it?
> 
> Driver can't support it right now but hardware can.
> 

DT is independent of some chosen (or current) Linux drivers. Imagine
Linux cannot support it but OpenBSD does.

As Mark pointed out, this needs a follow up commit.

Best regards,
Krzysztof

Re: [PATCH v3 1/4] spi: stm32: renaming of spi_master into spi_controller

[Leonard Göhrs]

Hello,

On 15.06.23 09:58, Valentin Caron wrote:
> From: Alain Volmat <alain.volmat@foss.st.com>
> 
> Preparing introduction of SPI device, rename the spi_master structure
> into spi_controller. This doesn't have any functional impact since
> spi_master was already a macro for spi_controller.
> Referring now to ctrl instead of master since the spi_controller
> structure might not be used as a master controller only.
> 
> Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
> Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
> ---
>   drivers/spi/spi-stm32.c | 154 ++++++++++++++++++++--------------------
>   1 file changed, 77 insertions(+), 77 deletions(-)
> 
> diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
> index d6598e4116bd..5d9439ae1c09 100644
> --- a/drivers/spi/spi-stm32.c
> +++ b/drivers/spi/spi-stm32.c

<snip>

> @@ -939,13 +939,13 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
>   
>   /**
>    * stm32_spi_prepare_msg - set up the controller to transfer a single message
> - * @master: controller master interface
> + * @ctrl: controller interface
>    * @msg: pointer to spi message
>    */
> -static int stm32_spi_prepare_msg(struct spi_master *master,
> +static int stm32_spi_prepare_msg(struct spi_controller *ctrl,
>   				 struct spi_message *msg)
>   {
> -	struct stm32_spi *spi = spi_master_get_devdata(master);
> +	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
>   	struct spi_device *spi_dev = msg->spi;
>   	struct device_node *np = spi_dev->dev.of_node;
>   	unsigned long flags;
> @@ -984,9 +984,9 @@ static int stm32_spi_prepare_msg(struct spi_master *master,
>   	if (spi->cfg->set_number_of_data) {
>   		int ret;
>   
> -		ret = spi_split_transfers_maxwords(master, msg,
> -						   STM32H7_SPI_TSIZE_MAX,
> -						   GFP_KERNEL | GFP_DMA);
> +		ret = spi_split_transfers_maxsize(ctrl, msg,
> +						  STM32H7_SPI_TSIZE_MAX,
> +						  GFP_KERNEL | GFP_DMA);
>   		if (ret)
>   			return ret;
>   	}

<snip>

this patch introduces a regression when transmitting large SPI transfers with
a word size != 8 bits. The regression is caused by effectively reverting commit
1e4929112507f ("spi: stm32: split large transfers based on word size instead of
bytes") by changing the call to spi_split_transfers_maxwords() back to
spi_split_transfers_maxsize().

I've sent a patch[1] that fixes this regression by changing the …_maxsize()
call back to …_maxwords().

[1]: https://lore.kernel.org/all/20230816145237.3159817-1-l.goehrs@pengutronix.de/