All of lore.kernel.org
 help / color / mirror / Atom feed
From: Marc Kleine-Budde <mkl@pengutronix.de>
To: Mark Brown <broonie@kernel.org>
Cc: Maxime Ripard <mripard@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
	linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	kernel@pengutronix.de, Marc Kleine-Budde <mkl@pengutronix.de>
Subject: [PATCH v2 10/10] spi: spi-sun6i: sun6i_spi_transfer_one(): enable RF_RDY interrupt only if needed
Date: Mon,  6 Jul 2020 16:34:43 +0200	[thread overview]
Message-ID: <20200706143443.9855-11-mkl@pengutronix.de> (raw)
In-Reply-To: <20200706143443.9855-1-mkl@pengutronix.de>

In sun6i_spi_transfer_one() the RX FIFO Ready (SUN6I_INT_CTL_RF_RDY) is
unconditionally enabled.

A RX interrupt is only needed, if more data than fits into the FIFO is going to
be received during this transfer. As the RX-FIFO is drained during transfer
complete interrupt, enable the RX FIFO Ready interrupt only if the data doesn't
fit into the FIFO.

Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 drivers/spi/spi-sun6i.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c
index bba9843c40c5..19238e1b76b4 100644
--- a/drivers/spi/spi-sun6i.c
+++ b/drivers/spi/spi-sun6i.c
@@ -190,7 +190,7 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
 	unsigned int mclk_rate, div, div_cdr1, div_cdr2, timeout;
 	unsigned int start, end, tx_time;
 	unsigned int trig_level;
-	unsigned int tx_len = 0;
+	unsigned int tx_len = 0, rx_len = 0;
 	int ret = 0;
 	u32 reg;
 
@@ -245,10 +245,12 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
 	 * If it's a TX only transfer, we don't want to fill the RX
 	 * FIFO with bogus data
 	 */
-	if (sspi->rx_buf)
+	if (sspi->rx_buf) {
 		reg &= ~SUN6I_TFR_CTL_DHB;
-	else
+		rx_len = tfr->len;
+	} else {
 		reg |= SUN6I_TFR_CTL_DHB;
+	}
 
 	/* We want to control the chip select manually */
 	reg |= SUN6I_TFR_CTL_CS_MANUAL;
@@ -302,8 +304,10 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
 	sun6i_spi_fill_fifo(sspi);
 
 	/* Enable the interrupts */
-	reg = SUN6I_INT_CTL_TC | SUN6I_INT_CTL_RF_RDY;
+	reg = SUN6I_INT_CTL_TC;
 
+	if (rx_len > sspi->fifo_depth)
+		reg |= SUN6I_INT_CTL_RF_RDY;
 	if (tx_len > sspi->fifo_depth)
 		reg |= SUN6I_INT_CTL_TF_ERQ;
 
-- 
2.27.0


WARNING: multiple messages have this Message-ID
From: Marc Kleine-Budde <mkl@pengutronix.de>
To: Mark Brown <broonie@kernel.org>
Cc: Maxime Ripard <mripard@kernel.org>,
	linux-spi@vger.kernel.org, Chen-Yu Tsai <wens@csie.org>,
	Marc Kleine-Budde <mkl@pengutronix.de>,
	kernel@pengutronix.de, linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 10/10] spi: spi-sun6i: sun6i_spi_transfer_one(): enable RF_RDY interrupt only if needed
Date: Mon,  6 Jul 2020 16:34:43 +0200	[thread overview]
Message-ID: <20200706143443.9855-11-mkl@pengutronix.de> (raw)
In-Reply-To: <20200706143443.9855-1-mkl@pengutronix.de>

In sun6i_spi_transfer_one() the RX FIFO Ready (SUN6I_INT_CTL_RF_RDY) is
unconditionally enabled.

A RX interrupt is only needed, if more data than fits into the FIFO is going to
be received during this transfer. As the RX-FIFO is drained during transfer
complete interrupt, enable the RX FIFO Ready interrupt only if the data doesn't
fit into the FIFO.

Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 drivers/spi/spi-sun6i.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c
index bba9843c40c5..19238e1b76b4 100644
--- a/drivers/spi/spi-sun6i.c
+++ b/drivers/spi/spi-sun6i.c
@@ -190,7 +190,7 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
 	unsigned int mclk_rate, div, div_cdr1, div_cdr2, timeout;
 	unsigned int start, end, tx_time;
 	unsigned int trig_level;
-	unsigned int tx_len = 0;
+	unsigned int tx_len = 0, rx_len = 0;
 	int ret = 0;
 	u32 reg;
 
@@ -245,10 +245,12 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
 	 * If it's a TX only transfer, we don't want to fill the RX
 	 * FIFO with bogus data
 	 */
-	if (sspi->rx_buf)
+	if (sspi->rx_buf) {
 		reg &= ~SUN6I_TFR_CTL_DHB;
-	else
+		rx_len = tfr->len;
+	} else {
 		reg |= SUN6I_TFR_CTL_DHB;
+	}
 
 	/* We want to control the chip select manually */
 	reg |= SUN6I_TFR_CTL_CS_MANUAL;
@@ -302,8 +304,10 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
 	sun6i_spi_fill_fifo(sspi);
 
 	/* Enable the interrupts */
-	reg = SUN6I_INT_CTL_TC | SUN6I_INT_CTL_RF_RDY;
+	reg = SUN6I_INT_CTL_TC;
 
+	if (rx_len > sspi->fifo_depth)
+		reg |= SUN6I_INT_CTL_RF_RDY;
 	if (tx_len > sspi->fifo_depth)
 		reg |= SUN6I_INT_CTL_TF_ERQ;
 
-- 
2.27.0


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  parent reply	other threads:[~2020-07-06 14:34 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-06 14:34 [PATCH v2 00/10] spi: spi-sun6i: One fix and some improvements Marc Kleine-Budde
2020-07-06 14:34 ` Marc Kleine-Budde
2020-07-06 14:34 ` [PATCH v2 01/10] spi: spi-sun6i: sun6i_spi_transfer_one(): fix setting of clock rate Marc Kleine-Budde
2020-07-06 14:34   ` Marc Kleine-Budde
2020-07-06 14:34 ` [PATCH v2 02/10] spi: spi-sun6i: sun6i_spi_transfer_one(): report effectivly used speed_hz of transfer Marc Kleine-Budde
2020-07-06 14:34   ` Marc Kleine-Budde
2020-07-06 14:34 ` [PATCH v2 03/10] spi: spi-sun6i: sun6i_spi_transfer_one(): remove useless goto Marc Kleine-Budde
2020-07-06 14:34   ` Marc Kleine-Budde
2020-07-06 14:34 ` [PATCH v2 04/10] spi: spi-sun6i: sun6i_spi_transfer_one(): remove not needed masking of transfer length Marc Kleine-Budde
2020-07-06 14:34   ` Marc Kleine-Budde
2020-07-06 14:34 ` [PATCH v2 05/10] spi: spi-sun6i: sun6i_spi_get_tx_fifo_count: Convert manual shift+mask to FIELD_GET() Marc Kleine-Budde
2020-07-06 14:34   ` Marc Kleine-Budde
2020-07-06 14:34 ` [PATCH v2 06/10] spi: spi-sun6i: sun6i_spi_drain_fifo(): introduce sun6i_spi_get_rx_fifo_count() and make use of it Marc Kleine-Budde
2020-07-06 14:34   ` Marc Kleine-Budde
2020-07-06 14:34 ` [PATCH v2 07/10] spi: spi-sun6i: sun6i_spi_drain_fifo(): remove not needed length argument Marc Kleine-Budde
2020-07-06 14:34   ` Marc Kleine-Budde
2020-07-06 14:34 ` [PATCH v2 08/10] spi: spi-sun6i: sun6i_spi_fill_fifo(): " Marc Kleine-Budde
2020-07-06 14:34   ` Marc Kleine-Budde
2020-07-06 14:34 ` [PATCH v2 09/10] spi: spi-sun6i: sun6i_spi_transfer_one(): collate write to Interrupt Control Register Marc Kleine-Budde
2020-07-06 14:34   ` Marc Kleine-Budde
2020-07-06 14:34 ` Marc Kleine-Budde [this message]
2020-07-06 14:34   ` [PATCH v2 10/10] spi: spi-sun6i: sun6i_spi_transfer_one(): enable RF_RDY interrupt only if needed Marc Kleine-Budde
2020-07-06 15:40 ` [PATCH v2 00/10] spi: spi-sun6i: One fix and some improvements Mark Brown
2020-07-06 15:40   ` Mark Brown
2020-07-06 18:52 ` Mark Brown
2020-07-06 18:52   ` Mark Brown
2020-07-06 19:02 ` Mark Brown
2020-07-06 19:02   ` Mark Brown
2020-07-07 14:17 ` Mark Brown
2020-07-07 14:17   ` Mark Brown

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200706143443.9855-11-mkl@pengutronix.de \
    --to=mkl@pengutronix.de \
    --cc=broonie@kernel.org \
    --cc=kernel@pengutronix.de \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-spi@vger.kernel.org \
    --cc=mripard@kernel.org \
    --cc=wens@csie.org \
    --subject='Re: [PATCH v2 10/10] spi: spi-sun6i: sun6i_spi_transfer_one(): enable RF_RDY interrupt only if needed' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.