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-rw-r--r--target/linux/ar71xx/patches-3.3/200-spi-ath79-add-delay-between-SCK-changes.patch122
1 files changed, 0 insertions, 122 deletions
diff --git a/target/linux/ar71xx/patches-3.3/200-spi-ath79-add-delay-between-SCK-changes.patch b/target/linux/ar71xx/patches-3.3/200-spi-ath79-add-delay-between-SCK-changes.patch
deleted file mode 100644
index 28cc1fbe93..0000000000
--- a/target/linux/ar71xx/patches-3.3/200-spi-ath79-add-delay-between-SCK-changes.patch
+++ /dev/null
@@ -1,122 +0,0 @@
-From cbb3ade4765bc715b5c2eae4a7b6eaf3ff7ad958 Mon Sep 17 00:00:00 2001
-From: Gabor Juhos <juhosg@openwrt.org>
-Date: Wed, 11 Jan 2012 20:06:35 +0100
-Subject: [PATCH 28/34] spi/ath79: add delay between SCK changes
-
-The driver uses the "as fast as it can" approach
-to drive the SCK signal. However this does not
-work with certain low speed SPI chips (e.g. the
-PCF2123 RTC chip). Add per-bit slowdowns in order
-to be able to use the driver with such chips as
-well.
-
-Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
----
- drivers/spi/spi-ath79.c | 44 +++++++++++++++++++++++++++++++++++++++++++-
- 1 files changed, 43 insertions(+), 1 deletions(-)
-
---- a/drivers/spi/spi-ath79.c
-+++ b/drivers/spi/spi-ath79.c
-@@ -24,17 +24,24 @@
- #include <linux/spi/spi_bitbang.h>
- #include <linux/bitops.h>
- #include <linux/gpio.h>
-+#include <linux/clk.h>
-+#include <linux/err.h>
-
- #include <asm/mach-ath79/ar71xx_regs.h>
- #include <asm/mach-ath79/ath79_spi_platform.h>
-
- #define DRV_NAME "ath79-spi"
-
-+#define ATH79_SPI_RRW_DELAY_FACTOR 12000
-+#define MHZ (1000 * 1000)
-+
- struct ath79_spi {
- struct spi_bitbang bitbang;
- u32 ioc_base;
- u32 reg_ctrl;
- void __iomem *base;
-+ struct clk *clk;
-+ unsigned rrw_delay;
- };
-
- static inline u32 ath79_spi_rr(struct ath79_spi *sp, unsigned reg)
-@@ -52,6 +59,12 @@ static inline struct ath79_spi *ath79_sp
- return spi_master_get_devdata(spi->master);
- }
-
-+static inline void ath79_spi_delay(struct ath79_spi *sp, unsigned nsecs)
-+{
-+ if (nsecs > sp->rrw_delay)
-+ ndelay(nsecs - sp->rrw_delay);
-+}
-+
- static void ath79_spi_chipselect(struct spi_device *spi, int is_active)
- {
- struct ath79_spi *sp = ath79_spidev_to_sp(spi);
-@@ -184,7 +197,9 @@ static u32 ath79_spi_txrx_mode0(struct s
-
- /* setup MSB (to slave) on trailing edge */
- ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, out);
-+ ath79_spi_delay(sp, nsecs);
- ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, out | AR71XX_SPI_IOC_CLK);
-+ ath79_spi_delay(sp, nsecs);
-
- word <<= 1;
- }
-@@ -198,6 +213,7 @@ static __devinit int ath79_spi_probe(str
- struct ath79_spi *sp;
- struct ath79_spi_platform_data *pdata;
- struct resource *r;
-+ unsigned long rate;
- int ret;
-
- master = spi_alloc_master(&pdev->dev, sizeof(*sp));
-@@ -239,12 +255,36 @@ static __devinit int ath79_spi_probe(str
- goto err_put_master;
- }
-
-+ sp->clk = clk_get(&pdev->dev, "ahb");
-+ if (IS_ERR(sp->clk)) {
-+ ret = PTR_ERR(sp->clk);
-+ goto err_unmap;
-+ }
-+
-+ ret = clk_enable(sp->clk);
-+ if (ret)
-+ goto err_clk_put;
-+
-+ rate = DIV_ROUND_UP(clk_get_rate(sp->clk), MHZ);
-+ if (!rate) {
-+ ret = -EINVAL;
-+ goto err_clk_disable;
-+ }
-+
-+ sp->rrw_delay = ATH79_SPI_RRW_DELAY_FACTOR / rate;
-+ dev_dbg(&pdev->dev, "register read/write delay is %u nsecs\n",
-+ sp->rrw_delay);
-+
- ret = spi_bitbang_start(&sp->bitbang);
- if (ret)
-- goto err_unmap;
-+ goto err_clk_disable;
-
- return 0;
-
-+err_clk_disable:
-+ clk_disable(sp->clk);
-+err_clk_put:
-+ clk_put(sp->clk);
- err_unmap:
- iounmap(sp->base);
- err_put_master:
-@@ -259,6 +299,8 @@ static __devexit int ath79_spi_remove(st
- struct ath79_spi *sp = platform_get_drvdata(pdev);
-
- spi_bitbang_stop(&sp->bitbang);
-+ clk_disable(sp->clk);
-+ clk_put(sp->clk);
- iounmap(sp->base);
- platform_set_drvdata(pdev, NULL);
- spi_master_put(sp->bitbang.master);