|
|
| (3 intermediate revisions by 2 users not shown) |
| Line 1: |
Line 1: |
| − | == The linux LED driver class ==
| + | #REDIRECT [[GPIO_LEDS]] |
| − | | + | |
| − | On recent kernel, linux have a led driver. This led can be driven from /sys/class/leds/ directory.
| + | |
| − | | + | |
| − | For APF28Dev, the led is configurable under the directory :
| + | |
| − | | + | |
| − | <pre class="apf">
| + | |
| − | # cd /sys/class/leds/apfdev:green:user
| + | |
| − | </pre>
| + | |
| − | | + | |
| − | === Blinking ===
| + | |
| − | | + | |
| − | The blinking style can be selected with ''trigger'' file. By defaut on APF28Dev, Heartbeat is selected :
| + | |
| − | | + | |
| − | <pre class="apf">
| + | |
| − | # cat /sys/class/leds/apfdev:green:user/trigger
| + | |
| − | none nand-disk mmc0 timer [heartbeat] backlight gpio default-on
| + | |
| − | </pre>
| + | |
| − | | + | |
| − | Blinking style can be changed with ''echo'' command :
| + | |
| − | | + | |
| − | <pre class="apf">
| + | |
| − | # echo "nand-disk" > /sys/class/leds/apfdev:green:user/trigger
| + | |
| − | # cat /sys/class/leds/apfdev:green:user/trigger
| + | |
| − | none [nand-disk] mmc0 timer heartbeat backlight gpio default-on
| + | |
| − | </pre>
| + | |
| − | | + | |
| − | With this "nand-disk" option selected, the led will blink each time nand access occur (try with ''sync'' command to see it blinking).
| + | |
| − | | + | |
| − | === Links ===
| + | |
| − | | + | |
| − | See the kernel documentation [http://www.mjmwired.net/kernel/Documentation/leds-class.txt Documentation/leds-class.txt] for more information about this driver.
| + | |
