iPod Classic: prepare i2c and PMU for bootloader

When the bootloader starts only IRAM is available, the first task is to
ask the PMU to verify if the iPod has previously been hibernated by OF.
Due to memory limitations, the kernel cannot be used on this stage.

This patch modifies I2C and PMU low level functions to not to depend
on kernel (removes mutexes, and uses HW timer instead of current_tick),
actual kernel functions are modified to be 'mutexed' wrappers of the new
functions.

Change-Id: I7cef9e95dedaf176dc0659315f3dc33166d5b116

1 files changed, 24 insertions, 0 deletions

diff --git a/firmware/target/arm/s5l8702/ipod6g/pmu-ipod6g.c b/firmware/target/arm/s5l8702/ipod6g/pmu-ipod6g.c
index 946beb1519..2a9236046c 100644
--- a/firmware/target/arm/s5l8702/ipod6g/pmu-ipod6g.c
+++ b/firmware/target/arm/s5l8702/ipod6g/pmu-ipod6g.c
@@ -142,3 +142,27 @@ void pmu_write_rtc(unsigned char* buffer)
 {
     pmu_write_multiple(0x59, 7, buffer);
 }
+
+#ifdef BOOTLOADER
+int pmu_rd_multiple(int address, int count, unsigned char* buffer)
+{
+    return i2c_rd(0, 0xe6, address, count, buffer);
+}
+
+int pmu_wr_multiple(int address, int count, unsigned char* buffer)
+{
+    return i2c_wr(0, 0xe6, address, count, buffer);
+}
+
+unsigned char pmu_rd(int address)
+{
+    unsigned char val;
+    pmu_rd_multiple(address, 1, &val);
+    return val;
+}
+
+int pmu_wr(int address, unsigned char val)
+{
+    return pmu_wr_multiple(address, 1, &val);
+}
+#endif /* BOOTLOADER */