{"id":16514,"date":"2024-11-18T17:01:57","date_gmt":"2024-11-18T09:01:57","guid":{"rendered":"https:\/\/fwq.ai\/blog\/16514\/"},"modified":"2024-11-18T17:01:57","modified_gmt":"2024-11-18T09:01:57","slug":"linux%e9%a9%b1%e5%8a%a8-%e5%9c%a8%e9%a9%b1%e5%8a%a8%e4%b8%ad%e5%88%9b%e5%bb%basysfs%e6%8e%a5%e5%8f%a3","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/16514\/","title":{"rendered":"Linux\u9a71\u52a8 | \u5728\u9a71\u52a8\u4e2d\u521b\u5efasysfs\u63a5\u53e3"},"content":{"rendered":"

<\/span>\u524d\u8a00<\/span> <\/span> <\/h2>\n

\u5728\u4e00\u4e9b\u5f00\u53d1\u677f\u4e2d\uff0c\u7ecf\u5e38\u53ef\u4ee5\u770b\u5230\u901a\u8fc7echo\u7684\u65b9\u5f0f\u6765\u76f4\u63a5\u63a7\u5236\u786c\u4ef6\u6216\u8005\u4fee\u6539\u9a71\u52a8\uff0c\u4f8b\u5982\uff1a<\/p>\n

\/\/\u706f\u706d\necho 0 &gt;\/sys\/class\/leds\/firefly:blue:power\/brightness \n\/\/\u706f\u4eae\necho 1 &gt;\/sys\/class\/leds\/firefly:blue:power\/brightness<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u8fd9\u662f\u600e\u4e48\u505a\u5230\u5462\uff1f<\/p>\n
\u5b9e\u9645\u4e0a\uff0c\u8fd9\u662f\u56e0\u4e3a\u5728\u9a71\u52a8\u4e2d\u63d0\u4f9b\u4e86sysfs\u63a5\u53e3\u7ed9\u7528\u6237\u4f7f\u7528\uff0c\u4f7f\u5f97\u7528\u6237\u53ef\u4ee5\u901a\u8fc7cat\u6216\u8005echo\u547d\u4ee4\u6765\u67e5\u770b\u548c\u4fee\u6539\u9a71\u52a8\u4e2d\u67d0\u4e9b\u53d8\u91cf\u7684\u503c\u3002<\/p>\n
\u4e0b\u9762\u4ecb\u7ecd\u9a71\u52a8\u4e2d\u521b\u5efasysfs\u63a5\u53e3\u7684\u65b9\u6cd5\u3002<\/p>\n
 <\/span>sysfs\u63a5\u53e3\u521b\u5efa<\/span> <\/span> <\/h2>\n
\u57fa\u672c\u6b65\u9aa4\uff1a<\/p>\n
1\u3001\u4f7f\u7528DEVICE_ATTR\u58f0\u660e\u4e00\u4e2asys\u8282\u70b9<\/strong><\/p>\n
static DEVICE_ATTR(led_status, 0600, led_status_show, led_status_store);<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
led_status\uff1a\u5728sys\u63a5\u53e3\u4e2d\u663e\u793a\u7684\u8282\u70b9\u540d\u5b57<\/p>\n
0600\uff1a\u8868\u793a\u64cd\u4f5c\u8fd9\u4e2aled_status\u8282\u70b9\u7684\u6743\u9650<\/p>\n
led_status_show\uff1a\u4f7f\u7528cat\u547d\u4ee4\u67e5\u770bsys\u63a5\u53e3\u65f6\u8c03\u7528\u7684\u51fd\u6570<\/p>\n
led_status_store\uff1a\u4f7f\u7528echo\u547d\u4ee4\u5f80sys\u63a5\u53e3\u5199\u5165\u5185\u5bb9\u65f6\u8c03\u7528\u7684\u51fd\u6570<\/p>\n
2\u3001\u5b8c\u6210sys\u8282\u70b9\u7684\u8bfb\u5199\u51fd\u6570<\/strong><\/p>\n
static unsigned int led = 0;\n\/*\n*  sys\u8282\u70b9\u7684\u8bfb\u51fd\u6570\n*  \u6267\u884c cat \/sys\/devices\/platform\/leds\/led_status\u65f6\u4f1a\u8c03\u7528\n*\/\nstatic ssize_t led_status_show(struct device *dev, struct device_attribute *attr, char *buf)\n{\n  \/\/buf\u662f\u901a\u8fc7cat\u547d\u4ee4\u663e\u793a\u5230\u7ec8\u7aef\u7684\u5185\u5bb9\uff0c\u8fd9\u91cc\u663e\u793aled\u53d8\u91cf\n return sprintf(buf, \"%s:%d.\n\", \"led\", led);\n}\n\n\/**\n*  sys\u8282\u70b9\u7684\u5199\u51fd\u6570\n*  \u7528echo\u547d\u4ee4\u5f80sys\u8282\u70b9\u5199\u5165\u5185\u5bb9\u65f6\uff0c\u4f1a\u8c03\u7528\u8be5\u51fd\u6570\n*\/\nstatic ssize_t led_status_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)\n{\n  \/\/\u5199\u5165\u7684\u5185\u5bb9\u4f1a\u5b58\u653e\u5230buf\u4e2d\uff0c\u8fd9\u91cc\u5c06buf\u5185\u5bb9\u8d4b\u503c\u7ed9led\u53d8\u91cf\n sscanf(buf, \"%d\", &amp;led);\n\n return count;\n}<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u793a\u4f8b\u4e2d\uff0cled_status_show()\u51fd\u6570\u548cled_status_store()\u51fd\u6570\u7684\u4f5c\u7528\u5206\u4e3a\u6253\u5370led\u53d8\u91cf\u7684\u503c<\/strong>\u548c\u4fee\u6539led\u53d8\u91cf\u7684\u503c<\/strong>.<\/p>\n
3\u3001\u5b9a\u4e49struct attribute\u548cstruct attribute_group\u6570\u7ec4<\/strong><\/p>\n
static struct attribute *led_attributes[]={\n \n  \/*\u4e0a\u8ff0\u4f7f\u7528\u4e86DEVICE_ATTR\u58f0\u660e\u8282\u70b9\u540d\u5b57\u4e3aled_status\uff0c\n  * \u5219struct attribute\u540d\u5b57\u5e94\u4e3a\uff1a\n  *  dev_attr_ + (\u8282\u70b9\u540d) + .attr\n  * \u6240\u4ee5\u540d\u5b57\u4e3adev_attr_led_status.attr\n  *\/\n  &amp;dev_attr_led_status.attr,\n NULL,\n};\n\n\nstatic const struct attribute_group led_attrs={\n .attrs = led_attributes,\/\/\u5f15\u7528\u4e0a\u8ff0struct attribute\u6570\u7ec4\n};<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u4e0a\u8ff0\u4f7f\u7528\u4e86DEVICE_ATTR\u58f0\u660e\u8282\u70b9\u540d\u5b57\u4e3aled_status\uff0c \u5219struct attribute\u540d\u5b57\u5e94\u4e3a\uff1adev_attr_ + (\u8282\u70b9\u540d) + .attr\u3002\u6240\u4ee5\u540d\u5b57\u4e3adev_attr_led_status.attr\u3002<\/p>\n
4\u3001\u5728probe\u51fd\u6570\u4e2d\u8c03\u7528sysfs_create_group()\u51fd\u6570\u6ce8\u518csysfs\u63a5\u53e3<\/strong><\/p>\n
 <\/span>\u5b8c\u6574\u4f8b\u5b50<\/span> <\/span> <\/h2>\n
\u8bbe\u5907\u6811\uff1a<\/p>\n
 leds:leds{\n  compatible = \"xx,xx-led\";\n };<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u9a71\u52a8\uff1a<\/p>\n
static unsigned int led = 0;\n\nstatic ssize_t led_status_show(struct device *dev, struct device_attribute *attr, char *buf)\n{\n return sprintf(buf, \"%s:%d.\n\", \"led\", led);\n}\n\nstatic ssize_t led_status_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)\n{\n sscanf(buf, \"%d\", &amp;led);\n\n return count;\n}\n\nstatic DEVICE_ATTR(led_status, 0600, led_status_show, led_status_store);\n\nstatic struct attribute *led_attributes[]={\n &amp;dev_attr_led_status.attr,\n NULL,\n};\n\n\nstatic const struct attribute_group led_attrs={\n .attrs = led_attributes,\n};\n\nstatic int xx_led_probe(struct platform_device *pdev)\n{\n sysfs_create_group(&amp;pdev-&gt;dev.kobj, &amp;led_attrs);\n return 0;\n}\n\nstatic int xx_led_remove(struct platform_device *pdev)\n{\n sysfs_remove_group(&amp;pdev-&gt;dev.kobj, &amp;led_attrs);\n return 0;\n}\n\nstatic const struct of_device_id xx_led_of_match[] = {\n {.compatible = \"xx,xx-led\"},\n};\n\n\nstatic struct platform_driver xx_led_driver = {\n .probe = xx_led_probe,\n .remove = xx_led_remove,\n .driver = {\n  .name = \"xx-led\",\n  .owner = THIS_MODULE,\n  .of_match_table = xx_led_of_match,\n },\n};\n\nstatic int __init xx_led_init(void)\n{\n return platform_driver_register(&amp;xx_led_driver );\n}\n\nstatic void __exit xx_led_exit(void)\n{\n platform_driver_unregister(&amp;xx_led_driver);\n}\n\nmodule_init(xx_led_init);\nmodule_exit(xx_led_exit);\n\nMODULE_LICENSE(\"GPL\");\nMODULE_DESCRIPTION(\"xx led driver\");\nMODULE_AUTHOR(\"Vincent\");\nMODULE_VERSION(\"V1.0.00\");<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u9a71\u52a8\u52a0\u8f7d\u540e\uff0c\u5c31\u53ef\u4ee5\u5728linux\u7ec8\u7aef\u4e2d\uff0c\u4f7f\u7528cat\u548cecho\u547d\u4ee4\u6765\u67e5\u770b\u548c\u4fee\u6539\u9a71\u52a8\u4e2dled\u53d8\u91cf\u7684\u503c\u3002\u4f8b\u5982\uff1a<\/p>\n
\/\/\u67e5\u770bled\u53d8\u91cf\u7684\u503c\ncat \/sys\/devices\/platform\/leds\/led_status\nled:0.\n\n\/\/\u4fee\u6539led\u53d8\u91cf\u7684\u503c\u4e3a9\necho 9 &gt; \/sys\/devices\/platform\/leds\/led_status\n\/\/\u67e5\u770b\ncat \/sys\/devices\/platform\/leds\/led_status\nled:9.<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u4ee5\u4e0a\u5c31\u662fLinux\u9a71\u52a8 | \u5728\u9a71\u52a8\u4e2d\u521b\u5efasysfs\u63a5\u53e3\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
\u524d\u8a00 \u5728\u4e00\u4e9b\u5f00\u53d1\u677f\u4e2d\uff0c\u7ecf\u5e38\u53ef\u4ee5\u770b\u5230\u901a\u8fc7echo\u7684\u65b9\u5f0f\u6765\u76f4\u63a5\u63a7\u5236\u786c\u4ef6\u6216\u8005\u4fee\u6539\u9a71\u52a8\uff0c\u4f8b\u5982\uff1a \/\/\u706f\u706d echo 0 &gt;\/sys\/class\/leds\/firefly:blue:power\/brightness  \/\/\u706f\u4eae echo 1 &gt;\/sys\/class\/leds\/firefly:blue:power\/brightness \u767b\u5f55\u540e\u590d\u5236 \u8fd9\u662f\u600e\u4e48\u505a\u5230\u5462\uff1f \u5b9e\u9645\u4e0a\uff0c\u8fd9\u662f\u56e0\u4e3a\u5728\u9a71\u52a8\u4e2d\u63d0\u4f9b\u4e86sysfs\u63a5\u53e3\u7ed9\u7528\u6237\u4f7f\u7528\uff0c\u4f7f\u5f97\u7528\u6237\u53ef\u4ee5\u901a\u8fc7cat\u6216\u8005echo\u547d\u4ee4\u6765\u67e5\u770b\u548c\u4fee\u6539\u9a71\u52a8\u4e2d\u67d0\u4e9b\u53d8\u91cf\u7684\u503c\u3002 \u4e0b\u9762\u4ecb\u7ecd\u9a71\u52a8\u4e2d\u521b\u5efasysfs\u63a5\u53e3\u7684\u65b9\u6cd5\u3002 sysfs\u63a5\u53e3\u521b\u5efa \u57fa\u672c\u6b65\u9aa4\uff1a 1\u3001\u4f7f\u7528DEVICE_ATTR\u58f0\u660e\u4e00\u4e2asys\u8282\u70b9 static DEVICE_ATTR(led_status, 0600, led_status_show, led_status_store); \u767b\u5f55\u540e\u590d\u5236 led_status\uff1a\u5728sys\u63a5\u53e3\u4e2d\u663e\u793a\u7684\u8282\u70b9\u540d\u5b57 0600\uff1a\u8868\u793a\u64cd\u4f5c\u8fd9\u4e2aled_status\u8282\u70b9\u7684\u6743\u9650 led_status_show\uff1a\u4f7f\u7528cat\u547d\u4ee4\u67e5\u770bsys\u63a5\u53e3\u65f6\u8c03\u7528\u7684\u51fd\u6570 led_status_store\uff1a\u4f7f\u7528echo\u547d\u4ee4\u5f80sys\u63a5\u53e3\u5199\u5165\u5185\u5bb9\u65f6\u8c03\u7528\u7684\u51fd\u6570 2\u3001\u5b8c\u6210sys\u8282\u70b9\u7684\u8bfb\u5199\u51fd\u6570 static unsigned int led = 0; \/* *  sys\u8282\u70b9\u7684\u8bfb\u51fd\u6570 *  \u6267\u884c cat \/sys\/devices\/platform\/leds\/led_status\u65f6\u4f1a\u8c03\u7528 *\/ static ssize_t led_status_show(struct device *dev, struct device_attribute *attr, char *buf) {   \/\/buf\u662f\u901a\u8fc7cat\u547d\u4ee4\u663e\u793a\u5230\u7ec8\u7aef\u7684\u5185\u5bb9\uff0c\u8fd9\u91cc\u663e\u793aled\u53d8\u91cf  return sprintf(buf, “%s:%d. “, “led”, led); } \/** *  sys\u8282\u70b9\u7684\u5199\u51fd\u6570 *  \u7528echo\u547d\u4ee4\u5f80sys\u8282\u70b9\u5199\u5165\u5185\u5bb9\u65f6\uff0c\u4f1a\u8c03\u7528\u8be5\u51fd\u6570 *\/ static ssize_t led_status_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) {   \/\/\u5199\u5165\u7684\u5185\u5bb9\u4f1a\u5b58\u653e\u5230buf\u4e2d\uff0c\u8fd9\u91cc\u5c06buf\u5185\u5bb9\u8d4b\u503c\u7ed9led\u53d8\u91cf  sscanf(buf, “%d”, &amp;led);  return count; } \u767b\u5f55\u540e\u590d\u5236 \u793a\u4f8b\u4e2d\uff0cled_status_show()\u51fd\u6570\u548cled_status_store()\u51fd\u6570\u7684\u4f5c\u7528\u5206\u4e3a\u6253\u5370led\u53d8\u91cf\u7684\u503c\u548c\u4fee\u6539led\u53d8\u91cf\u7684\u503c. 3\u3001\u5b9a\u4e49struct attribute\u548cstruct attribute_group\u6570\u7ec4 static struct attribute *led_attributes[]={     \/*\u4e0a\u8ff0\u4f7f\u7528\u4e86DEVICE_ATTR\u58f0\u660e\u8282\u70b9\u540d\u5b57\u4e3aled_status\uff0c   * \u5219struct attribute\u540d\u5b57\u5e94\u4e3a\uff1a   *  dev_attr_ + (\u8282\u70b9\u540d) + .attr   * \u6240\u4ee5\u540d\u5b57\u4e3adev_attr_led_status.attr   *\/   &amp;dev_attr_led_status.attr,  NULL, […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[],"class_list":["post-16514","post","type-post","status-publish","format-standard","hentry","category-os"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/16514","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=16514"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/16514\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=16514"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=16514"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=16514"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}