#include <linux/of_gpio.h> #include <linux/gpio.h> #include <linux/delay.h> #include <linux/module.h> #include <linux/types.h> #include <linux/kobject.h>
2、定義全局變量和定義打開和關(guān)閉的接口并組織屬性數(shù)組：
// add zhaojr gpio63 for close or speaker pa enable
struct kobject *spk_pa_kobj = NULL;
unsigned int gpio63_spk_pa_gpio; //for speaker pa ic enable
//extern unsigned int gpio63_spk_pa_gpio;
static unsigned int SpkPa_Gpio_Enable = 0;
static ssize_t spkpaon_store(struct device *dev, struct device_attribute *attr,const char *buf, size_t count)
{
unsigned int ret=0;
//ret = kstrtoint(buf, 10, &backlight_enable);
ret = kstrtouint(buf, 10, &SpkPa_Gpio_Enable);
if (ret < 0){
pr_err(%s::kstrtouint() failed \\\\n, __func__);
}
pr_err(%s: SpkPa_Gpio_Enable=%d \\\\n, __func__,SpkPa_Gpio_Enable);
if(SpkPa_Gpio_Enable > 0){
//gpio_set_value(gpio63_spk_pa_gpio, 1);
pr_err(%s: gpio_set_value gpio63 speaker pa enable \\\\n, __func__);
//功放打開的時序
gpio_set_value(gpio63_spk_pa_gpio,0);
udelay(8);
gpio_set_value(gpio63_spk_pa_gpio,1);
udelay(8);
gpio_set_value(gpio63_spk_pa_gpio,0);
udelay(8);
gpio_set_value(gpio63_spk_pa_gpio,1);
//sdm660_cdc->ext_spk_pa_set = true;
}else{
pr_err(%s: gpio_set_value gpio63 speaker pa disable \\\\n, __func__);
//功放關(guān)閉的時序
gpio_set_value(gpio63_spk_pa_gpio,0);
udelay(600);
//sdm660_cdc->ext_spk_pa_set = false;
}
return count;
}
static ssize_t spkpaon_show(struct device *dev,struct device_attribute *attr, char *buf)
{
return sprintf(buf, %d\\\\n,SpkPa_Gpio_Enable);
}
static DEVICE_ATTR(spkpaon, 0664, spkpaon_show, spkpaon_store);
static struct attribute *spkpa_attributes[] = {
&dev_attr_spkpaon.attr,
NULL
};
static const struct attribute_group apkpa_attr_group = {
.attrs = spkpa_attributes,
NULL
};
//end zhaojr add
3、在probe()函數(shù)中添加文件系統(tǒng)屬性接口的注冊：
在注冊的時候并不需要對功放進(jìn)行初始化，所以probe()函數(shù)中并沒有對sdm660_cdc->spk_pa_gpio(GPIO63)，只操作了請求。具體的請求操作請參考：msm8953 audio部分的EAR和Speaker輸出的聲音配置中的音頻部分的
vendor/qcom/opensource/audio-kernel/asoc/codecs/sdm660_cdc/msm-analog-cdc.c文件操作
static int msm_anlg_cdc_probe(struct platform_device *pdev)
{
int ret = 0;
struct sdm660_cdc_priv *sdm660_cdc = NULL;
struct sdm660_cdc_pdata *pdata;
int adsp_state;
..................................
dev_set_drvdata(&pdev->dev, sdm660_cdc);
//kangting add
sdm660_cdc->spk_pa_gpio = of_get_named_gpio(pdev->dev.of_node, qcom,speaker-pa, 0);
if (!gpio_is_valid(sdm660_cdc->spk_pa_gpio))
pr_err(%s, sdm660_cdc->spk_pa_gpio not specified\\\\n,__func__);
else{
pr_err(%s, sdm660_cdc->spk_pa_gpio is %d\\\\n,__func__,sdm660_cdc->spk_pa_gpio);
ret = gpio_request(sdm660_cdc->spk_pa_gpio, spk_pa);
if (ret) {
pr_err(request spk_pa_gpio failed, ret=%d\\\\n,ret);
gpio_free(sdm660_cdc->spk_pa_gpio);
}
}
//kangting end
ret = snd_soc_register_codec(&pdev->dev,
&soc_codec_dev_sdm660_cdc,
msm_anlg_cdc_i2s_dai,
ARRAY_SIZE(msm_anlg_cdc_i2s_dai));
if (ret) {
dev_err(&pdev->dev,
%s:snd_soc_register_codec failed with error %d\\\\n,
__func__, ret);
goto err_supplies;
}
BLOCKING_INIT_NOTIFIER_HEAD(&sdm660_cdc->notifier);
BLOCKING_INIT_NOTIFIER_HEAD(&sdm660_cdc->notifier_mbhc);
//add by zhaojr
gpio63_spk_pa_gpio = sdm660_cdc->spk_pa_gpio; //將設(shè)備樹種定義的IO口號獲取進(jìn)來
spk_pa_kobj = kobject_create_and_add(spk_pa, NULL); //創(chuàng)建/sys/spk_pa/目錄
ret = sysfs_create_group(spk_pa_kobj, &apkpa_attr_group); //創(chuàng)建/sys/class/spk_pa/spkpaon節(jié)點
if (ret)
dev_err(&pdev->dev,%s:sysfs_create_group failed with error\\\\n,__func__);
//end zhaojr add
....................................
4、在remove函數(shù)中釋放資源
static int msm_anlg_cdc_remove(struct platform_device *pdev)
{
struct sdm660_cdc_priv *sdm660_cdc = dev_get_drvdata(&pdev->dev);
struct sdm660_cdc_pdata *pdata = sdm660_cdc->dev->platform_data;
int count;
//add by zhaojr //釋放資源
gpio_free(sdm660_cdc->spk_pa_gpio);
kobject_put(spk_pa_kobj); //關(guān)鍵函數(shù)
sysfs_remove_group(spk_pa_kobj, &apkpa_attr_group); //關(guān)鍵函數(shù)
//end zhaojr add
for (count = 0; count < sdm660_cdc->child_count &&
count < ANLG_CDC_CHILD_DEVICES_MAX; count )
platform_device_unregister(
sdm660_cdc->pdev_child_devices[count]);
snd_soc_unregister_codec(&pdev->dev);
msm_anlg_cdc_disable_supplies(sdm660_cdc, pdata);
wcd9xxx_spmi_irq_exit();
devm_kfree(&pdev->dev, sdm660_cdc);
return 0;
}
總結(jié)
到此這篇關(guān)于解析linux或android添加文件系統(tǒng)的屬性接口的方法的文章就介紹到這了,更多相關(guān)linux 文件系統(tǒng)的屬性接口內(nèi)容請搜索三五互聯(lián)以前的文章或繼續(xù)瀏覽下面的相關(guān)文章希望大家以后多多支持三五互聯(lián)！
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