#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閉的接口并組織屬性數組：
// 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()函數中添加文件系統屬性接口的注冊：
在注冊的時候并不需要對功放進行初始化，所以probe()函數中并沒有對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; //將設備樹種定義的IO口號獲取進來
spk_pa_kobj = kobject_create_and_add(spk_pa, NULL); //創建/sys/spk_pa/目錄
ret = sysfs_create_group(spk_pa_kobj, &apkpa_attr_group); //創建/sys/class/spk_pa/spkpaon節點
if (ret)
dev_err(&pdev->dev,%s:sysfs_create_group failed with error\\\\n,__func__);
//end zhaojr add
....................................
4、在remove函數中釋放資源
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); //關鍵函數
sysfs_remove_group(spk_pa_kobj, &apkpa_attr_group); //關鍵函數
//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
到此這篇關于解析linux或android添加文件系統的屬性接口的方法的文章就介紹到這了,更多相關linux 文件系統的屬性接口內容請搜索三五互聯以前的文章或繼續瀏覽下面的相關文章希望大家以后多多支持三五互聯！
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