[PATCH v2 3/5] spi: stm32: move splitting transfers to optimize_message

From: David Lechner
Date: Mon Feb 19 2024 - 17:35:36 EST


Since splitting transfers was moved to spi_optimize_message() in the
core SPI code, we now need to use the optimize_message callback in the
STM32 SPI driver to ensure that the operation is only performed once
when spi_optimize_message() is used by peripheral drivers explicitly.

Signed-off-by: David Lechner <dlechner@xxxxxxxxxxxx>
---

v2 changes: none

drivers/spi/spi-stm32.c | 28 ++++++++++++++++------------
1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index c32e57bb38bd..e4e7ddb7524a 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -1118,6 +1118,21 @@ static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
return IRQ_HANDLED;
}

+static int stm32_spi_optimize_message(struct spi_message *msg)
+{
+ struct spi_controller *ctrl = msg->spi->controller;
+ struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
+
+ /* On STM32H7, messages should not exceed a maximum size set
+ * later via the set_number_of_data function. In order to
+ * ensure that, split large messages into several messages
+ */
+ if (spi->cfg->set_number_of_data)
+ return spi_split_transfers_maxwords(ctrl, msg, spi->t_size_max);
+
+ return 0;
+}
+
/**
* stm32_spi_prepare_msg - set up the controller to transfer a single message
* @ctrl: controller interface
@@ -1163,18 +1178,6 @@ static int stm32_spi_prepare_msg(struct spi_controller *ctrl,
!!(spi_dev->mode & SPI_LSB_FIRST),
!!(spi_dev->mode & SPI_CS_HIGH));

- /* On STM32H7, messages should not exceed a maximum size setted
- * afterward via the set_number_of_data function. In order to
- * ensure that, split large messages into several messages
- */
- if (spi->cfg->set_number_of_data) {
- int ret;
-
- ret = spi_split_transfers_maxwords(ctrl, msg, spi->t_size_max);
- if (ret)
- return ret;
- }
-
spin_lock_irqsave(&spi->lock, flags);

/* CPOL, CPHA and LSB FIRST bits have common register */
@@ -2180,6 +2183,7 @@ static int stm32_spi_probe(struct platform_device *pdev)
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->optimize_message = stm32_spi_optimize_message;
ctrl->prepare_message = stm32_spi_prepare_msg;
ctrl->transfer_one = stm32_spi_transfer_one;
ctrl->unprepare_message = stm32_spi_unprepare_msg;

--
2.43.2