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
--
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next prev 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
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