<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Hi Samuel,<div class="">Thanks for your reply, I am using AST2500.</div><div class="">I tried add gpio-hog settings into my device tree, and yes, the GPIO works as it defined.</div><div class="">But all GPIOs defined by gpio-hog can not be modified in user space by gpioset / gpioget utility.</div><div class="">I need to set all GPIOs to pre-defined state and can change it at run time.</div><div class="">Set GPIOs in Device tree is trying to lock it by a fixed direction and value.</div><div class=""><br class=""></div><div class="">Thanks.</div><div class=""><div class=""><div><br class=""><blockquote type="cite" class=""><div class="">On May 7, 2019, at 4:16 PM, Samuel Jiang <<a href="mailto:chyishian.jiang@gmail.com" class="">chyishian.jiang@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class="">
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<div dir="auto" class="">Hi Brad,
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<div dir="auto" class="">You could pre-define GPIOs setting on linux kernel device tree when loading kernel.</div>
<div dir="auto" class="">I’m not sure which SoC you used. Maybe you could direct apply you wanted on linux/arch/arm/boot/dts folder or custom create once. Hope the information could help you.</div>
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<div class="matchFont">Thanks,
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<div style="font-size: 14px; font-family: -apple-system, BlinkMacSystemFont, sans-serif;" class="">Samuel Jiang</div>
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<div name="messageReplySection" style="font-size: 14px; font-family: -apple-system, BlinkMacSystemFont, sans-serif;" class="">On May 7, 2019, 2:47 PM +0800, Brad Chou <<a href="mailto:chou.brad@gmail.com" class="">chou.brad@gmail.com</a>>, wrote:<br class="">
<blockquote type="cite" class="spark_quote" style="margin: 5px 5px; padding-left: 10px; border-left: thin solid #1abc9c;">Hi All,<br class="">
Is there a way to set ALL GPIOs to a pre-defined initial in/out direction and high/low value ?<br class="">
I see there is a gpio_defs.json, but seems only the direction can be set, ie. In or out, not high / low settings.<br class="">
Now, I am using a shell script with gpioset utility to do the job.<br class="">
But I know using shell to do it is a bad idea.<br class="">
Does anyone have better ideas ?<br class="">
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Thanks.</blockquote>
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