# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1563922440 -7200
# Node ID 6a5b49213ca2737f6676ec342d31de841fb158a8
# Parent  e60d54c4797f4d91ab148f625cc0e27a9c4ad82b
Added some convenience functions and some tentative RTC device inspection.

diff -r e60d54c4797f -r 6a5b49213ca2 pkg/landfall-examples/ci20_i2c/ci20_i2c.c
--- a/pkg/landfall-examples/ci20_i2c/ci20_i2c.c	Wed Jul 24 00:51:30 2019 +0200
+++ b/pkg/landfall-examples/ci20_i2c/ci20_i2c.c	Wed Jul 24 00:54:00 2019 +0200
@@ -126,6 +126,34 @@
   return jz4780_i2c_have_written(i2c_channel);
 }
 
+static long i2c_get(void *i2c_channel, uint8_t reg, uint8_t *buffer, long length, l4_cap_idx_t irqcap)
+{
+  long pos;
+
+  buffer[0] = reg;
+  i2c_write(i2c_channel, buffer, 1, irqcap);
+
+  memset(buffer, 0, length);
+  pos = i2c_read(i2c_channel, buffer, length, irqcap);
+
+  jz4780_i2c_stop(i2c_channel);
+
+  return pos;
+}
+
+static void i2c_report(void *i2c_channel, uint8_t *buffer, long length)
+{
+  if (!jz4780_i2c_failed(i2c_channel))
+  {
+    printf("Read: ");
+    while (length--)
+      printf("%02x", *(buffer++));
+    printf("\n");
+  }
+  else
+    printf("Read failed.\n");
+}
+
 static void i2c_scan(void *i2c_channel, l4_cap_idx_t irqcap)
 {
   uint8_t buf[1];
@@ -144,10 +172,7 @@
       printf("\n");
 
     jz4780_i2c_set_target(i2c_channel, address);
-    buf[0] = 0;
-    i2c_write(i2c_channel, buf, 1, irqcap);
-    i2c_read(i2c_channel, buf, 1, irqcap);
-    jz4780_i2c_stop(i2c_channel);
+    i2c_get(i2c_channel, 0, buf, 1, irqcap);
 
     if (!jz4780_i2c_failed(i2c_channel))
       printf("%02x ", address);
@@ -178,11 +203,7 @@
      See: drivers/video/fbdev/core/fb_ddc.c */
 
   jz4780_i2c_set_target(i2c_channel, 0x50);
-  buf[0] = 0;
-  i2c_write(i2c_channel, buf, 1, irqcap);
-  memset(buf, 0, 128);
-  pos = i2c_read(i2c_channel, buf, 128, irqcap);
-  jz4780_i2c_stop(i2c_channel);
+  pos = i2c_get(i2c_channel, 0, buf, 128, irqcap);
 
   if (pos <= 0)
   {
@@ -209,15 +230,8 @@
   /* Attempt to read from address 0x5a for PMIC OUT3. */
 
   jz4780_i2c_set_target(i2c_channel, 0x5a);
-  buf[0] = 0x32;
-  i2c_write(i2c_channel, buf, 1, irqcap);
-  i2c_read(i2c_channel, buf, 1, irqcap);
-  jz4780_i2c_stop(i2c_channel);
-
-  if (!jz4780_i2c_failed(i2c_channel))
-    printf("Read: %02x\n", buf[0]);
-  else
-    printf("Read failed.\n");
+  i2c_get(i2c_channel, 0x32, buf, 1, irqcap);
+  i2c_report(i2c_channel, buf, 1);
 
 #if 0
   /* Disable the regulator. */
@@ -232,16 +246,22 @@
   /* Read back from the register. Seemed to give 0xff, which makes no real
      sense, although the regulator did bring the voltage level low. */
 
-  buf[0] = 0x32;
-  i2c_write(i2c_channel, buf, 1, irqcap);
-  i2c_read(i2c_channel, buf, 1, irqcap);
-  jz4780_i2c_stop(i2c_channel);
+  i2c_get(i2c_channel, 0x32, buf, 1, irqcap);
+  i2c_report(i2c_channel, buf, 1);
+#endif
+}
 
-  if (!jz4780_i2c_failed(i2c_channel))
-    printf("Read: %02x\n", buf[0]);
-  else
-    printf("Read failed.\n");
-#endif
+static void rtc_control(void *i2c_channel, l4_cap_idx_t irqcap)
+{
+  /* Buffer for communicating. */
+
+  uint8_t buf[1];
+
+  /* Attempt to read from address 0x51 for RTC. */
+
+  jz4780_i2c_set_target(i2c_channel, 0x51);
+  i2c_get(i2c_channel, 0x0f, buf, 1, irqcap);
+  i2c_report(i2c_channel, buf, 1);
 }
 
 int main(void)
@@ -377,8 +397,8 @@
   jz4780_gpio_config_pad(gpio_port_d, PMSCL, Function_alt, 0);
   jz4780_gpio_config_pad(gpio_port_d, PMSDA, Function_alt, 0);
 
-  jz4780_gpio_config_pad(gpio_port_e, RTCSCL, Function_alt, 1);
-  jz4780_gpio_config_pad(gpio_port_e, RTCSDA, Function_alt, 1);
+  //jz4780_gpio_config_pad(gpio_port_e, RTCSCL, Function_alt, 1);
+  //jz4780_gpio_config_pad(gpio_port_e, RTCSDA, Function_alt, 1);
 
   jz4780_gpio_config_pad(gpio_port_f, DDCSCL, Function_alt, 1);
   jz4780_gpio_config_pad(gpio_port_f, DDCSDA, Function_alt, 1);
@@ -408,6 +428,8 @@
 
   ddc_read(i2c4, irq4cap);
 
+  //rtc_control(i2c4, irq4cap);
+
   jz4780_i2c_disable(i2c0);
   jz4780_i2c_disable(i2c4);