diff options
Diffstat (limited to 'target/linux/ar71xx/patches-3.8/005-spi-ath79-avoid-multiple-initialization-of-the-SPI-c.patch')
| -rw-r--r-- | target/linux/ar71xx/patches-3.8/005-spi-ath79-avoid-multiple-initialization-of-the-SPI-c.patch | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/target/linux/ar71xx/patches-3.8/005-spi-ath79-avoid-multiple-initialization-of-the-SPI-c.patch b/target/linux/ar71xx/patches-3.8/005-spi-ath79-avoid-multiple-initialization-of-the-SPI-c.patch new file mode 100644 index 0000000000..8ad1dc3a93 --- /dev/null +++ b/target/linux/ar71xx/patches-3.8/005-spi-ath79-avoid-multiple-initialization-of-the-SPI-c.patch @@ -0,0 +1,112 @@ +From d731c08cf1d264fd6113b9a97790c5a3a86ea520 Mon Sep 17 00:00:00 2001 +From: Gabor Juhos <juhosg@openwrt.org> +Date: Thu, 27 Dec 2012 10:42:28 +0100 +Subject: [PATCH] spi/ath79: avoid multiple initialization of the SPI + controller + +commit c4a31f43005512b366e8bfc346e7f14c1a7a1ba7 upstream. + +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> +Signed-off-by: Grant Likely <grant.likely@secretlab.ca> +--- + drivers/spi/spi-ath79.c | 41 ++++++++++++++++++++++++----------------- + 1 file 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) +@@ -268,12 +271,15 @@ static int ath79_spi_probe(struct platfo + 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: +@@ -292,6 +298,7 @@ static int ath79_spi_remove(struct platf + 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); |