From d563313ab1fff999ee79bc237f8861a832c36cce Mon Sep 17 00:00:00 2001
From: Francois Ramu <francois.ramu@st.com>
Date: Tue, 28 Sep 2021 11:30:34 +0200
Subject: [PATCH] drivers: spi: stm32 can support TI mode for the SPI frame
 format

Depending of the soc and SPI peripheral, the Frame-Format of the
SPI can be configured to support TI or Motorola protocol.
This is configured through a new DTS property.

Signed-off-by: Francois Ramu <francois.ramu@st.com>
---
 drivers/spi/spi_ll_stm32.c | 15 ++++++++++++++-
 drivers/spi/spi_ll_stm32.h | 10 ++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi_ll_stm32.c b/drivers/spi/spi_ll_stm32.c
index 45f130409d..bd2624b461 100644
--- a/drivers/spi/spi_ll_stm32.c
+++ b/drivers/spi/spi_ll_stm32.c
@@ -559,7 +559,11 @@ static int spi_stm32_configure(const struct device *dev,
 
 #if !defined(CONFIG_SOC_SERIES_STM32F1X) \
 	&& (!defined(CONFIG_SOC_SERIES_STM32L1X) || defined(SPI_CR2_FRF))
-	LL_SPI_SetStandard(spi, LL_SPI_PROTOCOL_MOTOROLA);
+	if (cfg->ti_mode) {
+		LL_SPI_SetStandard(spi, LL_SPI_PROTOCOL_TI);
+	} else {
+		LL_SPI_SetStandard(spi, LL_SPI_PROTOCOL_MOTOROLA);
+	}
 #endif
 
 	/* At this point, it's mandatory to set this on the context! */
@@ -924,6 +928,14 @@ static void spi_stm32_irq_config_func_##id(const struct device *dev)		\
 #define SPI_DMA_STATUS_SEM(id)
 #endif
 
+#if !defined(CONFIG_SOC_SERIES_STM32F1X) \
+	&& (!defined(CONFIG_SOC_SERIES_STM32L1X) || defined(SPI_CR2_FRF))
+#define STM32_SPI_TI_MODE_CONFIG(id)				\
+	.ti_mode = DT_INST_PROP(id, frame_format),
+#else
+#define STM32_SPI_TI_MODE_CONFIG(id)
+#endif
+
 #if DT_HAS_COMPAT_STATUS_OKAY(st_stm32_spi_subghz)
 #define STM32_SPI_USE_SUBGHZSPI_NSS_CONFIG(id)				\
 	.use_subghzspi_nss = DT_INST_PROP_OR(				\
@@ -948,6 +960,7 @@ static const struct spi_stm32_config spi_stm32_cfg_##id = {		\
 	.pinctrl_list_size = ARRAY_SIZE(spi_pins_##id),			\
 	STM32_SPI_IRQ_HANDLER_FUNC(id)					\
 	STM32_SPI_USE_SUBGHZSPI_NSS_CONFIG(id)				\
+	STM32_SPI_TI_MODE_CONFIG(id)					\
 };									\
 									\
 static struct spi_stm32_data spi_stm32_dev_data_##id = {		\
diff --git a/drivers/spi/spi_ll_stm32.h b/drivers/spi/spi_ll_stm32.h
index 69f074fc39..1d651fe8c3 100644
--- a/drivers/spi/spi_ll_stm32.h
+++ b/drivers/spi/spi_ll_stm32.h
@@ -19,6 +19,16 @@ struct spi_stm32_config {
 #ifdef CONFIG_SPI_STM32_INTERRUPT
 	irq_config_func_t irq_config;
 #endif
+
+#if !defined(CONFIG_SOC_SERIES_STM32F1X) \
+	&& (!defined(CONFIG_SOC_SERIES_STM32L1X) || defined(SPI_CR2_FRF))
+	/*
+	 * if supported by the instance, this bit will configure the frame-format
+	 * of the SPI to be compliant with the TI protocol.
+	 */
+	bool ti_mode;
+#endif
+
 #if DT_HAS_COMPAT_STATUS_OKAY(st_stm32_spi_subghz)
 	bool use_subghzspi_nss;
 #endif