From 1d0ee0c9df31c9fd1e4f8d7e2464e36fbf6e3f75 Mon Sep 17 00:00:00 2001 From: David Lechner Date: Mon, 28 Apr 2025 15:58:56 -0500 Subject: [PATCH] spi: axi-spi-engine: wait for completion in setup Add a polling wait for SPI instruction execution to complete in the spi_engine_setup() function. In practice, these instructions complete in a few 10s of nanoseconds, so we never ran into any race conditions, but it is good practice to wait for the completion of the SPI engine instructions before returning from the setup function. Signed-off-by: David Lechner Link: https://patch.msgid.link/20250428-adi-main-v1-1-4b8a1b88a212@baylibre.com Signed-off-by: Mark Brown --- drivers/spi/spi-axi-spi-engine.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-axi-spi-engine.c b/drivers/spi/spi-axi-spi-engine.c index da9840957778..d040deffa9bb 100644 --- a/drivers/spi/spi-axi-spi-engine.c +++ b/drivers/spi/spi-axi-spi-engine.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -739,12 +740,16 @@ static int spi_engine_setup(struct spi_device *device) { struct spi_controller *host = device->controller; struct spi_engine *spi_engine = spi_controller_get_devdata(host); + unsigned int reg; if (device->mode & SPI_CS_HIGH) spi_engine->cs_inv |= BIT(spi_get_chipselect(device, 0)); else spi_engine->cs_inv &= ~BIT(spi_get_chipselect(device, 0)); + writel_relaxed(SPI_ENGINE_CMD_SYNC(0), + spi_engine->base + SPI_ENGINE_REG_CMD_FIFO); + writel_relaxed(SPI_ENGINE_CMD_CS_INV(spi_engine->cs_inv), spi_engine->base + SPI_ENGINE_REG_CMD_FIFO); @@ -755,7 +760,11 @@ static int spi_engine_setup(struct spi_device *device) writel_relaxed(SPI_ENGINE_CMD_ASSERT(0, 0xff), spi_engine->base + SPI_ENGINE_REG_CMD_FIFO); - return 0; + writel_relaxed(SPI_ENGINE_CMD_SYNC(1), + spi_engine->base + SPI_ENGINE_REG_CMD_FIFO); + + return readl_relaxed_poll_timeout(spi_engine->base + SPI_ENGINE_REG_SYNC_ID, + reg, reg == 1, 1, 1000); } static int spi_engine_transfer_one_message(struct spi_controller *host, -- 2.50.1