openwrtv4/target/linux/ar71xx/patches-3.2/205-spi-ath79-avoid-multiple-initialization-of-the-SPI-c.patch
Gabor Juhos 102c6df148 ar71xx: improve SPI flash read/write performance
mtd_speedtest results:

                        page write speed
                    old         new       delta
DB120            209 KiB/s   226 KiB/s     +8.13%
TL-WR1043ND v1   122 KiB/s   148 KiB/s    +21.31%
TL-WR703N v1     153 KiB/s   194 KiB/s    +26.80%
TL-MR3220 v1     130 KiB/s   156 KiB/s    +20.00%
TL-WR2543ND v1   158 KiB/s   202 KiB/s    +27.85%
TL-WR741ND v2    122 KiB/s   152 KiB/s    +24.59%
ALFA AP96        229 KiB/s   260 KiB/s    +13.54%
WNDR3700         202 KiB/s   223 KiB/s    +10.40%

                         page read speed
                    old        new       delta
DB120            691 KiB/s   929 KiB/s    +34.44%
TL-WR1043ND v1   372 KiB/s   754 KiB/s   +102.69%
TL-WR703N v1     375 KiB/s   745 KiB/s    +98.67%
TL-MR3220 v1     372 KiB/s   752 KiB/s   +102.15%
TL-WR2543ND v1   307 KiB/s   564 KiB/s    +83.71%
TL-WR741ND v2    315 KiB/s   525 KiB/s    +66.67%
ALFA AP96        515 KiB/s   702 KiB/s    +36.31%
WNDR3700         515 KiB/s   697 KiB/s    +35.34%

SVN-Revision: 31117
2012-03-27 19:38:15 +00:00

108 lines
3 KiB
Diff

From 25e681989198e94656eab9df22b8b761abd2ae26 Mon Sep 17 00:00:00 2001
From: Gabor Juhos <juhosg@openwrt.org>
Date: Mon, 9 Jan 2012 15:00:46 +0100
Subject: [PATCH 5/7] spi/ath79: avoid multiple initialization of the SPI controller
Currently we are initializing the SPI controller in
the chip select line function, and that function is
called once for each SPI device on the bus. If a
board has multiple SPI devices, the controller will
be initialized multiple times.
Introduce ath79_spi_{en,dis}able helper functions,
and call those from probe/response in order to avoid
the mutliple initialization of the controller.
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
---
drivers/spi/spi-ath79.c | 41 ++++++++++++++++++++++++-----------------
1 files changed, 24 insertions(+), 17 deletions(-)
--- a/drivers/spi/spi-ath79.c
+++ b/drivers/spi/spi-ath79.c
@@ -96,16 +96,8 @@ static void ath79_spi_chipselect(struct
}
-static int ath79_spi_setup_cs(struct spi_device *spi)
+static void ath79_spi_enable(struct ath79_spi *sp)
{
- struct ath79_spi *sp = ath79_spidev_to_sp(spi);
- struct ath79_spi_controller_data *cdata;
- int status;
-
- cdata = spi->controller_data;
- if (spi->chip_select && !cdata)
- return -EINVAL;
-
/* enable GPIO mode */
ath79_spi_wr(sp, AR71XX_SPI_REG_FS, AR71XX_SPI_FS_GPIO);
@@ -115,6 +107,24 @@ static int ath79_spi_setup_cs(struct spi
/* TODO: setup speed? */
ath79_spi_wr(sp, AR71XX_SPI_REG_CTRL, 0x43);
+}
+
+static void ath79_spi_disable(struct ath79_spi *sp)
+{
+ /* restore CTRL register */
+ ath79_spi_wr(sp, AR71XX_SPI_REG_CTRL, sp->reg_ctrl);
+ /* disable GPIO mode */
+ ath79_spi_wr(sp, AR71XX_SPI_REG_FS, 0);
+}
+
+static int ath79_spi_setup_cs(struct spi_device *spi)
+{
+ struct ath79_spi_controller_data *cdata;
+ int status;
+
+ cdata = spi->controller_data;
+ if (spi->chip_select && !cdata)
+ return -EINVAL;
status = 0;
if (spi->chip_select) {
@@ -135,17 +145,10 @@ static int ath79_spi_setup_cs(struct spi
static void ath79_spi_cleanup_cs(struct spi_device *spi)
{
- struct ath79_spi *sp = ath79_spidev_to_sp(spi);
-
if (spi->chip_select) {
struct ath79_spi_controller_data *cdata = spi->controller_data;
gpio_free(cdata->gpio);
}
-
- /* restore CTRL register */
- ath79_spi_wr(sp, AR71XX_SPI_REG_CTRL, sp->reg_ctrl);
- /* disable GPIO mode */
- ath79_spi_wr(sp, AR71XX_SPI_REG_FS, 0);
}
static int ath79_spi_setup(struct spi_device *spi)
@@ -271,12 +274,15 @@ static __devinit int ath79_spi_probe(str
dev_dbg(&pdev->dev, "register read/write delay is %u nsecs\n",
sp->rrw_delay);
+ ath79_spi_enable(sp);
ret = spi_bitbang_start(&sp->bitbang);
if (ret)
- goto err_clk_disable;
+ goto err_disable;
return 0;
+err_disable:
+ ath79_spi_disable(sp);
err_clk_disable:
clk_disable(sp->clk);
err_clk_put:
@@ -295,6 +301,7 @@ static __devexit int ath79_spi_remove(st
struct ath79_spi *sp = platform_get_drvdata(pdev);
spi_bitbang_stop(&sp->bitbang);
+ ath79_spi_disable(sp);
clk_disable(sp->clk);
clk_put(sp->clk);
iounmap(sp->base);