1

Raspberry PI / gpio pin 26 on mld 5.0

« on: August 10, 2016, 15:04:37 »

I am running MLD linux 5.0 on a raspberry pi 2. The "made in China" case has a built-in lirc receiver on pin 26, so you need to give lirc_rpi an option:

/etc/modprobe.d/custom.conf: options lirc_rpi gpio_in_pin=26

Unfortunately, the lirc_rpi module thinks pin 26 is not a valid gpio pin. From the source:

int valid_gpio_pins[] = { 0, 1, 4, 8, 7, 9, 10, 11, 14, 15, 17, 18, 21, 22, 23, 24, 25 };

The easiest solution is taking a hex editor and edit /lib/modules/3.19.3.177/kernel/drivers/char/lirc_rpi.ko. Search for 0000001800000019 hex and change it to 000000180000001A hex. This adds the value '26' to the valid_gpio_pins[] array in lirc_rpi.c.

Reboot and you get:

[   27.998198] lirc_rpi: driver registered!
[   28.957066] lirc_rpi: auto-detected active low receiver on GPIO pin 26
[   29.528068] input: lircd as /devices/virtual/input/input0

I include the modified lirc_rpi.ko for mld linux 5.0.

2

Raspberry PI / DS3231 real-time clock

« on: April 07, 2016, 11:52:37 »

The following seems to work. In /etc/init.d/rpi-rtc, change ds1307 to ds3231:

Code: [Select]

--- rpi-rtc.ORIG 2016-04-07 11:00:27.198366313 +0200
+++ rpi-rtc 2016-04-07 11:00:38.574365795 +0200
@@ -7,7 +7,7 @@
  echo "Activate rtc:"
  i=0; while [ ! -e /dev/i2c-0 -a $i -lt 10 ]; do i=$(($i+1)); sleep 1; done
  rev=$(i2cdetect -y 0 2>/dev/null | grep -q 68 && echo 0 || echo 1)
- echo ds1307 0x68 2>/dev/null > /sys/class/i2c-adapter/i2c-$rev/new_device
+ echo ds3231 0x68 2>/dev/null > /sys/class/i2c-adapter/i2c-$rev/new_device
  check_status
  ;;
  stop)
After rebooting dmesg then shows:

Code: [Select]

[   23.443693] rtc-ds1307 1-0068: rtc core: registered ds3231 as rtc0
[   23.443765] i2c i2c-1: new_device: Instantiated device ds3231 at 0x68
Thanks everyone.

3

Raspberry PI / DS3231 real-time clock

« on: April 06, 2016, 13:14:18 »

I have the system package  rpi-rtc installed. It detects a ds1307, not a ds3231. This is normal? hwclock seems to work.

Code: [Select]

MLD> dmesg | grep rtc
[   22.880255] rtc-ds1307 1-0068: rtc core: registered ds1307 as rtc0
[   22.880318] rtc-ds1307 1-0068: 56 bytes nvram
MLD>  hwclock -r -u
Wed 06 Apr 2016 13:05:40 CEST  0.000000 seconds
MLD> cat /sys/bus/i2c/drivers/rtc-ds1307/1-0068/name
ds1307


4

Raspberry PI / DS3231 real-time clock

« on: April 05, 2016, 14:49:27 »

Hi.

I'm using MLD as vdr client on a raspberry pi 2. A question: is it possible to add support for DS3231 to the rpi-rtc system package?

DS3231 is a small real-time clock with battery back-up. Tested and works fine under raspbian. In case someone is interested where I bought mine: cost approx.1.07 euro, search for "DS3231 raspberry"  on aliexpress.com.

Thanks,

Koen