linux-spi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andy Shevchenko <andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
To: linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Andy Shevchenko
	<andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
Subject: [PATCH v1 06/10] spi: dw: eliminate speed variable in ->transfer_one()
Date: Wed, 14 Oct 2015 23:12:21 +0300	[thread overview]
Message-ID: <1444853545-59868-7-git-send-email-andriy.shevchenko@linux.intel.com> (raw)
In-Reply-To: <1444853545-59868-1-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>

There is no point to have a separate variable for speed in ->transfer_one().

While here, remove !chip->clk_div from a condition since it is assigned
simultaneously with chip->speed_hz. We can do this safely because
 a) transfer speed can't be higher than max_freq and therefore chip->clk_div
    can be 0 only when chip->speed_hz is 0, and
 b) transfer speed can't be 0, otherwise we will get division by zero
    exception.

Signed-off-by: Andy Shevchenko <andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
---
 drivers/spi/spi-dw.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
index f7e36db..5dae557 100644
--- a/drivers/spi/spi-dw.c
+++ b/drivers/spi/spi-dw.c
@@ -285,8 +285,7 @@ static int dw_spi_transfer_one(struct spi_master *master,
 	struct chip_data *chip = spi_get_ctldata(spi);
 	u8 imask = 0;
 	u16 txlevel = 0;
-	u16 clk_div = 0;
-	u32 speed = 0;
+	u16 clk_div;
 	u32 cr0;
 	int ret;
 
@@ -301,14 +300,11 @@ static int dw_spi_transfer_one(struct spi_master *master,
 	spi_enable_chip(dws, 0);
 
 	/* Handle per transfer options for bpw and speed */
-	speed = chip->speed_hz;
-	if ((transfer->speed_hz != speed) || !chip->clk_div) {
-		speed = transfer->speed_hz;
-
+	if (transfer->speed_hz != chip->speed_hz) {
 		/* clk_div doesn't support odd number */
-		clk_div = (dws->max_freq / speed + 1) & 0xfffe;
+		clk_div = (dws->max_freq / transfer->speed_hz + 1) & 0xfffe;
 
-		chip->speed_hz = speed;
+		chip->speed_hz = transfer->speed_hz;
 		chip->clk_div = clk_div;
 
 		spi_set_clk(dws, chip->clk_div);
-- 
2.5.3

--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

  parent reply	other threads:[~2015-10-14 20:12 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-10-14 20:12 [PATCH v1 00/10] spi: dw: bug fix and clean up series Andy Shevchenko
     [not found] ` <1444853545-59868-1-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-14 20:12   ` [PATCH v1 01/10] spi: dw: explicitly free IRQ handler in dw_spi_remove_host() Andy Shevchenko
     [not found]     ` <1444853545-59868-2-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:29       ` Mark Brown
2015-10-14 20:12   ` [PATCH v1 02/10] spi: dw: use plain struct device * at earlier ->probe() Andy Shevchenko
     [not found]     ` <1444853545-59868-3-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:43       ` Applied "spi: dw: use plain struct device * at earlier ->probe()" to the spi tree Mark Brown
2015-10-14 20:12   ` [PATCH v1 03/10] spi: dw: remove unneeded cr0 member of struct chip_data Andy Shevchenko
     [not found]     ` <1444853545-59868-4-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:43       ` Applied "spi: dw: remove unneeded cr0 member of struct chip_data" to the spi tree Mark Brown
2015-10-14 20:12   ` [PATCH v1 04/10] spi: dw: remove a NULL check when call ->remove() Andy Shevchenko
     [not found]     ` <1444853545-59868-5-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:32       ` Mark Brown
2015-10-14 20:12   ` [PATCH v1 05/10] spi: dw: remove bits_per_word member of struct chip_data Andy Shevchenko
     [not found]     ` <1444853545-59868-6-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:43       ` Applied "spi: dw: remove bits_per_word member of struct chip_data" to the spi tree Mark Brown
2015-10-14 20:12   ` Andy Shevchenko [this message]
     [not found]     ` <1444853545-59868-7-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:43       ` Applied "spi: dw: eliminate speed variable in ->transfer_one()" " Mark Brown
2015-10-14 20:12   ` [PATCH v1 07/10] spi: dw: eliminate unused threshold variables Andy Shevchenko
     [not found]     ` <1444853545-59868-8-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:43       ` Applied "spi: dw: eliminate unused threshold variables" to the spi tree Mark Brown
2015-10-14 20:12   ` [PATCH v1 08/10] spi: dw: introduce spi_shutdown_chip() Andy Shevchenko
     [not found]     ` <1444853545-59868-9-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:43       ` Applied "spi: dw: introduce spi_shutdown_chip()" to the spi tree Mark Brown
2015-10-14 20:12   ` [PATCH v1 09/10] spi: dw-pci: remove unused pdev member from struct dw_spi_pci Andy Shevchenko
     [not found]     ` <1444853545-59868-10-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:43       ` Applied "spi: dw-pci: remove unused pdev member from struct dw_spi_pci" to the spi tree Mark Brown
2015-10-14 20:12   ` [PATCH v1 10/10] spi: dw-mmio: convert to unified device property API Andy Shevchenko
     [not found]     ` <1444853545-59868-11-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2015-10-19 19:43       ` Applied "spi: dw-mmio: convert to unified device property API" to the spi tree 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=1444853545-59868-7-git-send-email-andriy.shevchenko@linux.intel.com \
    --to=andriy.shevchenko-vuqaysv1563yd54fqh9/ca@public.gmane.org \
    --cc=broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
    --cc=linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    /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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).