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From:   Sudip Mukherjee <sudip.mukherjee@sifive.com>
To:     Serge Semin <fancer.lancer@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
Cc:     greentime.hu@sifive.com, jude.onyenegecha@sifive.com,
        william.salmon@sifive.com, adnan.chowdhury@sifive.com,
        ben.dooks@sifive.com, linux-spi@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        jeegar.lakhani@sifive.com,
        Sudip Mukherjee <sudip.mukherjee@sifive.com>
Subject: [PATCH 07/11] spi: dw: update NDF while writing in enhanced spi mode
Date:   Tue,  2 Aug 2022 18:57:51 +0100
Message-Id: <20220802175755.6530-8-sudip.mukherjee@sifive.com>
In-Reply-To: <20220802175755.6530-1-sudip.mukherjee@sifive.com>
References: <20220802175755.6530-1-sudip.mukherjee@sifive.com>
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If the transfer of Transmit only mode is using dual/quad/octal SPI then
NDF needs to be updated with the number of data frames.
If the Transmit FIFO goes empty in-between, DWC_ssi masks the serial
clock and wait for rest of the data until the programmed amount of
frames are transferred successfully.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@sifive.com>
---
 drivers/spi/spi-dw-core.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c
index 9d499bdf2ce6..8cb30540ad5b 100644
--- a/drivers/spi/spi-dw-core.c
+++ b/drivers/spi/spi-dw-core.c
@@ -344,7 +344,9 @@ void dw_spi_update_config(struct dw_spi *dws, struct spi_device *spi,
 	dw_writel(dws, DW_SPI_CTRLR0, cr0);
 
 	if (cfg->tmode == DW_SPI_CTRLR0_TMOD_EPROMREAD ||
-	    cfg->tmode == DW_SPI_CTRLR0_TMOD_RO)
+	    cfg->tmode == DW_SPI_CTRLR0_TMOD_RO ||
+	    (cfg->tmode == DW_SPI_CTRLR0_TMOD_TO &&
+	     (dws->caps & DW_SPI_CAP_EXT_SPI) && cfg->spi_frf))
 		dw_writel(dws, DW_SPI_CTRLR1, cfg->ndf ? cfg->ndf - 1 : 0);
 
 	/* Note DW APB SSI clock divider doesn't support odd numbers */
@@ -760,6 +762,8 @@ static int dw_spi_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op)
 		cfg.ndf = op->data.nbytes;
 	} else {
 		cfg.tmode = DW_SPI_CTRLR0_TMOD_TO;
+		if (enhanced_spi)
+			cfg.ndf = op->data.nbytes;
 	}
 
 	dw_spi_enable_chip(dws, 0);
-- 
2.30.2