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From: kernel-TqfNSX0MhmxHKSADF0wUEw@public.gmane.org
To: Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
	Eric Anholt <eric-WhKQ6XTQaPysTnJN9+BGXg@public.gmane.org>,
	Stefan Wahren <stefan.wahren-eS4NqCHxEME@public.gmane.org>,
	linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-rpi-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
	linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
Subject: [PATCH 4/5] spi: bcm2835: support effective_speed_hz
Date: Sat, 23 Feb 2019 08:49:51 +0000	[thread overview]
Message-ID: <20190223084952.14758-5-kernel@martin.sperl.org> (raw)
In-Reply-To: <20190223084952.14758-1-kernel-TqfNSX0MhmxHKSADF0wUEw@public.gmane.org>

From: Martin Sperl <kernel-TqfNSX0MhmxHKSADF0wUEw@public.gmane.org>

Setting spi_transfer->effective_speed_hz in transfer_one so that
it can get used in cs_change_delay configured with delay as a muliple
of SPI clock cycles.

Signed-off-by: Martin Sperl <kernel-TqfNSX0MhmxHKSADF0wUEw@public.gmane.org>
---
 drivers/spi/spi-bcm2835.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c
index 35aebdfd3b4e..c2912c1e09c5 100644
--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -777,7 +777,6 @@ static int bcm2835_spi_transfer_one(struct spi_master *master,
 {
 	struct bcm2835_spi *bs = spi_master_get_devdata(master);
 	unsigned long spi_hz, clk_hz, cdiv;
-	unsigned long spi_used_hz;
 	unsigned long long xfer_time_us;
 	u32 cs = bcm2835_rd(bs, BCM2835_SPI_CS);

@@ -797,7 +796,7 @@ static int bcm2835_spi_transfer_one(struct spi_master *master,
 	} else {
 		cdiv = 0; /* 0 is the slowest we can go */
 	}
-	spi_used_hz = cdiv ? (clk_hz / cdiv) : (clk_hz / 65536);
+	tfr->effective_speed_hz = cdiv ? (clk_hz / cdiv) : (clk_hz / 65536);
 	bcm2835_wr(bs, BCM2835_SPI_CLK, cdiv);

 	/* handle all the 3-wire mode */
@@ -823,7 +822,7 @@ static int bcm2835_spi_transfer_one(struct spi_master *master,
 	xfer_time_us = (unsigned long long)tfr->len
 		* 9 /* clocks/byte - SPI-HW waits 1 clock after each byte */
 		* 1000000;
-	do_div(xfer_time_us, spi_used_hz);
+	do_div(xfer_time_us, tfr->effective_speed_hz);

 	/* for short requests run polling*/
 	if (xfer_time_us <= BCM2835_SPI_POLLING_LIMIT_US)
--
2.11.0

  parent reply	other threads:[~2019-02-23  8:49 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-02-23  8:49 [PATCH 0/5] allow to define cs deassert times in us, ns and SCK-len kernel
     [not found] ` <20190223084952.14758-1-kernel-TqfNSX0MhmxHKSADF0wUEw@public.gmane.org>
2019-02-23  8:49   ` [PATCH 1/5] spi: core: allow defining time that cs is deasserted kernel-TqfNSX0MhmxHKSADF0wUEw
     [not found]     ` <20190223084952.14758-2-kernel-TqfNSX0MhmxHKSADF0wUEw@public.gmane.org>
2019-05-08  9:34       ` Applied "spi: core: allow defining time that cs is deasserted" to the spi tree Mark Brown
2019-02-23  8:49   ` kernel-TqfNSX0MhmxHKSADF0wUEw [this message]
2019-05-13 15:14     ` [PATCH 4/5] spi: bcm2835: support effective_speed_hz Mark Brown
2019-02-23  8:49 ` [PATCH 2/5] spi: core: allow reporting the effectivly used speed_hz for a transfer kernel
2019-02-23  8:49 ` [PATCH 3/5] spi: core: allow defining time that cs is deasserted as a multiple of SCK kernel
     [not found]   ` <20190223124010.y7lsncknnxoblvgz@wunner.de>
     [not found]     ` <20190223124010.y7lsncknnxoblvgz-JFq808J9C/izQB+pC5nmwQ@public.gmane.org>
2019-02-23 13:15       ` kernel-TqfNSX0MhmxHKSADF0wUEw
     [not found]         ` <20190224103913.bjw7g6ievr75iawz@wunner.de>
     [not found]           ` <20190224103913.bjw7g6ievr75iawz-JFq808J9C/izQB+pC5nmwQ@public.gmane.org>
2019-02-24 11:03             ` kernel-TqfNSX0MhmxHKSADF0wUEw
2019-02-26 11:37               ` Mark Brown
2019-05-07 10:07                 ` kernel

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