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authorImre Kaloz <kaloz@openwrt.org>2014-03-07 11:27:00 +0000
committerImre Kaloz <kaloz@openwrt.org>2014-03-07 11:27:00 +0000
commit2b43bb49dec4546cdca7e627b06e7682ae742591 (patch)
tree0d58c3ccdefbe53983cda5399612b4727f0ee81d /target/linux/generic/patches-3.14/861-04_spi_gpio_implement_spi_delay.patch
parent3be7023c9be4e1381699ce393638ad63565c9ac5 (diff)
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add preliminary 3.14 support
Signed-off-by: Imre Kaloz <kaloz@openwrt.org> git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39789 3c298f89-4303-0410-b956-a3cf2f4a3e73
Diffstat (limited to 'target/linux/generic/patches-3.14/861-04_spi_gpio_implement_spi_delay.patch')
-rw-r--r--target/linux/generic/patches-3.14/861-04_spi_gpio_implement_spi_delay.patch58
1 files changed, 58 insertions, 0 deletions
diff --git a/target/linux/generic/patches-3.14/861-04_spi_gpio_implement_spi_delay.patch b/target/linux/generic/patches-3.14/861-04_spi_gpio_implement_spi_delay.patch
new file mode 100644
index 0000000000..6cbe4c3ee3
--- /dev/null
+++ b/target/linux/generic/patches-3.14/861-04_spi_gpio_implement_spi_delay.patch
@@ -0,0 +1,58 @@
+Implement the SPI-GPIO delay function for busses that need speed limitation.
+
+--mb
+
+
+
+--- a/drivers/spi/spi-gpio.c
++++ b/drivers/spi/spi-gpio.c
+@@ -22,6 +22,7 @@
+ #include <linux/init.h>
+ #include <linux/platform_device.h>
+ #include <linux/gpio.h>
++#include <linux/delay.h>
+ #include <linux/of.h>
+ #include <linux/of_device.h>
+ #include <linux/of_gpio.h>
+@@ -74,6 +75,7 @@ struct spi_gpio {
+ * #define SPI_MOSI_GPIO 120
+ * #define SPI_SCK_GPIO 121
+ * #define SPI_N_CHIPSEL 4
++ * #undef NEED_SPIDELAY
+ * #include "spi-gpio.c"
+ */
+
+@@ -81,6 +83,7 @@ struct spi_gpio {
+ #define DRIVER_NAME "spi_gpio"
+
+ #define GENERIC_BITBANG /* vs tight inlines */
++#define NEED_SPIDELAY 1
+
+ /* all functions referencing these symbols must define pdata */
+ #define SPI_MISO_GPIO ((pdata)->miso)
+@@ -131,12 +134,20 @@ static inline int getmiso(const struct s
+ #undef pdata
+
+ /*
+- * NOTE: this clocks "as fast as we can". It "should" be a function of the
+- * requested device clock. Software overhead means we usually have trouble
+- * reaching even one Mbit/sec (except when we can inline bitops), so for now
+- * we'll just assume we never need additional per-bit slowdowns.
++ * NOTE: to clock "as fast as we can", set spi_device.max_speed_hz
++ * and spi_transfer.speed_hz to 0.
++ * Otherwise this is a function of the requested device clock.
++ * Software overhead means we usually have trouble
++ * reaching even one Mbit/sec (except when we can inline bitops). So on small
++ * embedded devices with fast SPI slaves you usually don't need a delay.
+ */
+-#define spidelay(nsecs) do {} while (0)
++static inline void spidelay(unsigned nsecs)
++{
++#ifdef NEED_SPIDELAY
++ if (unlikely(nsecs))
++ ndelay(nsecs);
++#endif /* NEED_SPIDELAY */
++}
+
+ #include "spi-bitbang-txrx.h"
+