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-rw-r--r--include/linux/scx200_gpio.h96
1 files changed, 96 insertions, 0 deletions
diff --git a/include/linux/scx200_gpio.h b/include/linux/scx200_gpio.h
new file mode 100644
index 000000000000..30cdd648ba79
--- /dev/null
+++ b/include/linux/scx200_gpio.h
@@ -0,0 +1,96 @@
+#include <linux/spinlock.h>
+
+u32 scx200_gpio_configure(int index, u32 set, u32 clear);
+
+extern unsigned scx200_gpio_base;
+extern long scx200_gpio_shadow[2];
+
+#define scx200_gpio_present() (scx200_gpio_base!=0)
+
+/* Definitions to make sure I do the same thing in all functions */
+#define __SCx200_GPIO_BANK unsigned bank = index>>5
+#define __SCx200_GPIO_IOADDR unsigned short ioaddr = scx200_gpio_base+0x10*bank
+#define __SCx200_GPIO_SHADOW long *shadow = scx200_gpio_shadow+bank
+#define __SCx200_GPIO_INDEX index &= 31
+
+#define __SCx200_GPIO_OUT __asm__ __volatile__("outsl":"=mS" (shadow):"d" (ioaddr), "0" (shadow))
+
+/* returns the value of the GPIO pin */
+
+static inline int scx200_gpio_get(int index) {
+ __SCx200_GPIO_BANK;
+ __SCx200_GPIO_IOADDR + 0x04;
+ __SCx200_GPIO_INDEX;
+
+ return (inl(ioaddr) & (1<<index)) ? 1 : 0;
+}
+
+/* return the value driven on the GPIO signal (the value that will be
+ driven if the GPIO is configured as an output, it might not be the
+ state of the GPIO right now if the GPIO is configured as an input) */
+
+static inline int scx200_gpio_current(int index) {
+ __SCx200_GPIO_BANK;
+ __SCx200_GPIO_INDEX;
+
+ return (scx200_gpio_shadow[bank] & (1<<index)) ? 1 : 0;
+}
+
+/* drive the GPIO signal high */
+
+static inline void scx200_gpio_set_high(int index) {
+ __SCx200_GPIO_BANK;
+ __SCx200_GPIO_IOADDR;
+ __SCx200_GPIO_SHADOW;
+ __SCx200_GPIO_INDEX;
+ set_bit(index, shadow);
+ __SCx200_GPIO_OUT;
+}
+
+/* drive the GPIO signal low */
+
+static inline void scx200_gpio_set_low(int index) {
+ __SCx200_GPIO_BANK;
+ __SCx200_GPIO_IOADDR;
+ __SCx200_GPIO_SHADOW;
+ __SCx200_GPIO_INDEX;
+ clear_bit(index, shadow);
+ __SCx200_GPIO_OUT;
+}
+
+/* drive the GPIO signal to state */
+
+static inline void scx200_gpio_set(int index, int state) {
+ __SCx200_GPIO_BANK;
+ __SCx200_GPIO_IOADDR;
+ __SCx200_GPIO_SHADOW;
+ __SCx200_GPIO_INDEX;
+ if (state)
+ set_bit(index, shadow);
+ else
+ clear_bit(index, shadow);
+ __SCx200_GPIO_OUT;
+}
+
+/* toggle the GPIO signal */
+static inline void scx200_gpio_change(int index) {
+ __SCx200_GPIO_BANK;
+ __SCx200_GPIO_IOADDR;
+ __SCx200_GPIO_SHADOW;
+ __SCx200_GPIO_INDEX;
+ change_bit(index, shadow);
+ __SCx200_GPIO_OUT;
+}
+
+#undef __SCx200_GPIO_BANK
+#undef __SCx200_GPIO_IOADDR
+#undef __SCx200_GPIO_SHADOW
+#undef __SCx200_GPIO_INDEX
+#undef __SCx200_GPIO_OUT
+
+/*
+ Local variables:
+ compile-command: "make -C ../.. bzImage modules"
+ c-basic-offset: 8
+ End:
+*/