Applied "spi: lpspi: Let watermark change with send data length" to the spi tree

[Mark Brown <broonie@xxxxxxxxxx>]

The patch

   spi: lpspi: Let watermark change with send data length

has been applied to the spi tree at

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

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

>From cf86874bb9bdb99ba3620428b59b0408fbc703d0 Mon Sep 17 00:00:00 2001
From: Clark Wang <xiaoning.wang@xxxxxxx>
Date: Fri, 7 Dec 2018 02:50:38 +0000
Subject: [PATCH] spi: lpspi: Let watermark change with send data length

Configure watermark to change with the length of the sent data.
Support LPSPI sending message shorter than tx/rxfifosize.

Signed-off-by: Clark Wang <xiaoning.wang@xxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
 drivers/spi/spi-fsl-lpspi.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index cbf165e7bd17..08dcc3c22e88 100644
--- a/drivers/spi/spi-fsl-lpspi.c
+++ b/drivers/spi/spi-fsl-lpspi.c
@@ -89,6 +89,7 @@ struct fsl_lpspi_data {
 	void (*rx)(struct fsl_lpspi_data *);
 
 	u32 remain;
+	u8 watermark;
 	u8 txfifosize;
 	u8 rxfifosize;
 
@@ -235,7 +236,7 @@ static void fsl_lpspi_set_watermark(struct fsl_lpspi_data *fsl_lpspi)
 {
 	u32 temp;
 
-	temp = fsl_lpspi->txfifosize >> 1 | (fsl_lpspi->rxfifosize >> 1) << 16;
+	temp = fsl_lpspi->watermark >> 1 | (fsl_lpspi->watermark >> 1) << 16;
 
 	writel(temp, fsl_lpspi->base + IMX7ULP_FCR);
 
@@ -261,7 +262,8 @@ static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi)
 	if (prescale == 8 && scldiv >= 256)
 		return -EINVAL;
 
-	writel(scldiv, fsl_lpspi->base + IMX7ULP_CCR);
+	writel(scldiv | (scldiv << 8) | ((scldiv >> 1) << 16),
+					fsl_lpspi->base + IMX7ULP_CCR);
 
 	dev_dbg(fsl_lpspi->dev, "perclk=%d, speed=%d, prescale =%d, scldiv=%d\n",
 		perclk_rate, config.speed_hz, prescale, scldiv);
@@ -329,6 +331,11 @@ static void fsl_lpspi_setup_transfer(struct spi_device *spi,
 		fsl_lpspi->tx = fsl_lpspi_buf_tx_u32;
 	}
 
+	if (t->len <= fsl_lpspi->txfifosize)
+		fsl_lpspi->watermark = t->len;
+	else
+		fsl_lpspi->watermark = fsl_lpspi->txfifosize;
+
 	fsl_lpspi_config(fsl_lpspi);
 }
 
-- 
2.19.0.rc2