add driver for Semtech SC606 LED driver (for backlight and button LEDs)

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@10676 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 182 insertions, 0 deletions

diff --git a/firmware/target/arm/gigabeat/meg-fx/sc606-meg-fx.c b/firmware/target/arm/gigabeat/meg-fx/sc606-meg-fx.c
new file mode 100644
index 0000000000..b4e55083e3
--- /dev/null
+++ b/firmware/target/arm/gigabeat/meg-fx/sc606-meg-fx.c
@@ -0,0 +1,182 @@
+#include "config.h"
+#include "cpu.h"
+#include <stdbool.h>
+#include "kernel.h"
+#include "system.h"
+#include "hwcompat.h"
+#include "logf.h"
+#include "debug.h"
+#include "string.h"
+
+#define SLAVE_ADDRESS 0xCC
+
+#define SDA_LO     GPHDAT &= ~(1 << 9)
+#define SDA_HI     GPHDAT |= (1 << 9)
+#define SDA_INPUT  GPHCON &= ~(3 << 18)
+#define SDA_OUTPUT GPHCON |= (1 << 18)
+#define SDA        GPHDAT & (1 << 9)
+
+#define SCL_LO     GPHDAT &= ~(1 << 10)
+#define SCL_HI     GPHDAT |= (1 << 10)
+#define SCL_INPUT  GPHCON &= ~(3 << 20)
+#define SCL_OUTPUT GPHCON |= (1 << 20)
+#define SCL        GPHDAT & (1 << 10)
+
+#define SCL_SDA_HI    GPHDAT |= (3 << 9)
+
+/* arbitrary delay loop */
+#define DELAY   do { int _x; for(_x=0;_x<2000;_x++);} while (0)
+
+void sc606_i2c_start(void)
+{
+    SCL_SDA_HI;
+    DELAY;
+    SDA_LO;
+    DELAY;
+    SCL_LO;
+}
+
+void sc606_i2c_restart(void)
+{
+    SCL_SDA_HI;
+    DELAY;
+    SDA_LO;
+    DELAY;
+    SCL_LO;
+}
+
+void sc606_i2c_stop(void)
+{
+    SDA_LO;
+    DELAY;
+    SCL_HI;
+    DELAY;
+    SDA_HI;
+    DELAY;
+}
+
+void sc606_i2c_ack()
+{
+
+    SDA_LO;
+    SCL_HI;
+    DELAY;
+    SCL_LO;
+}
+
+int sc606_i2c_getack(void)
+{
+    int ret = 0;
+
+    /* Don't need a delay since this follows a data bit with a delay on the end */
+    SDA_INPUT;   /* And set to input */
+    SCL_HI;
+    DELAY;
+
+    if (SDA) /* ack failed */
+        ret = 1;
+
+    DELAY;
+    SCL_LO;
+    DELAY;
+    SDA_OUTPUT;
+    return ret;
+}
+
+int sc606_i2c_outb(unsigned char byte)
+{
+    int i;
+
+    /* clock out each bit, MSB first */
+    for (i = 0x80; i; i >>= 1) {
+
+       if (i & byte) {
+           SDA_HI;
+       } else {
+           SDA_LO;
+       }
+
+       DELAY;
+       SCL_HI;
+       DELAY;
+       SCL_LO;
+       DELAY;
+    }
+
+    return sc606_i2c_getack();
+}
+
+unsigned char sc606_i2c_inb()
+{
+   int i;
+   unsigned char byte = 0;
+
+   SDA_INPUT;   /* And set to input */
+   /* clock in each bit, MSB first */
+   for (i = 0x80; i; i >>= 1) {
+       SCL_HI;
+
+       if (SDA)
+           byte |= i;
+
+       SCL_LO;
+   }
+   SDA_OUTPUT;
+
+   sc606_i2c_ack();
+
+   return byte;
+}
+
+int sc606_write(unsigned char reg, unsigned char data)
+{
+    int x = 0;
+
+    sc606_i2c_start();
+    x += sc606_i2c_outb(SLAVE_ADDRESS);
+    x += 0x10 * sc606_i2c_outb(reg);
+    sc606_i2c_start();
+/*    sc606_i2c_restart(); */
+    x += 0x100 * sc606_i2c_outb(SLAVE_ADDRESS);
+    x += 0x1000 *sc606_i2c_outb(data);
+    sc606_i2c_stop();
+
+    return x;
+}
+
+int sc606_read(unsigned char reg, unsigned char* data)
+{
+    int x = 0;
+
+    sc606_i2c_start();
+    sc606_i2c_outb(SLAVE_ADDRESS);
+    sc606_i2c_outb(reg);
+    sc606_i2c_restart();
+    sc606_i2c_outb(SLAVE_ADDRESS | 1);
+    *data = sc606_i2c_inb();
+    sc606_i2c_stop();
+
+    return x;
+}
+
+void sc606_init()
+{
+    /* Set GPB2 (EN) to 1 */
+    GPBCON = (GPBCON & ~(3<<4)) | 1<<4;
+
+    /* Turn enable line on */
+    GPBDAT |= 1<<2;
+    /* OFF GPBDAT &= ~(1 << 2); */
+
+    /* About 400us - needs 350us */
+    DELAY;
+    DELAY;
+    DELAY;
+    DELAY;
+    DELAY;
+
+    /* Set GPH9 (SDA) and GPH10 (SCL) to 1 */
+    GPHUP &= ~(3<<9);
+    GPHCON = (GPHCON & ~(0xF<<18)) | 5<<18;
+}
+