[documentation][device_driver_model] Add pinctrl Chinese documentation - complete module 4/26

Co-authored-by: BernardXiong <1241087+BernardXiong@users.noreply.github.com>

documentation/6.components/device-driver/device_driver_model/pinctrl/README_zh.md

@@ -0,0 +1,627 @@
+# Pin Control (Pinctrl) 框架
+
+## 概述
+
+Pin Control 框架提供了一个统一的接口来管理 SoC 的引脚功能复用和配置。现代 SoC 通常具有多功能引脚，可以配置为不同的功能（如 GPIO、UART、SPI 等）并具有各种电气属性（上拉、下拉、驱动强度等）。
+
+### RT-Thread 实现
+
+RT-Thread 的 Pinctrl 框架集成了设备驱动模型，允许：
+
+- 基于设备树的引脚配置
+- 运行时引脚功能切换
+- 引脚状态管理（用于电源管理）
+- 与 GPIO 框架协同工作
+- 通过 SCMI 进行引脚控制
+
+## Kconfig 配置
+
+### 主要配置选项
+
+#### RT_USING_PINCTRL
+
+启用 Pin Control 框架支持。
+
+**路径**: `RT-Thread Components` → `Device Drivers` → `Using Pin Control (pinctrl)`
+
+**说明**: 启用后可以使用设备树配置引脚功能和参数。
+
+#### RT_PINCTRL_SCMI
+
+通过 SCMI (System Control and Management Interface) 协议进行引脚控制。
+
+**路径**: `RT-Thread Components` → `Device Drivers` → `Using Pin Control (pinctrl)` → `Enable SCMI pinctrl driver`
+
+**说明**: 用于带有专用系统控制处理器的系统。
+
+#### RT_PINCTRL_SINGLE
+
+Simple pinctrl driver 支持单寄存器引脚配置。
+
+**路径**: `RT-Thread Components` → `Device Drivers` → `Using Pin Control (pinctrl)` → `Enable simple pinctrl driver`
+
+**说明**: 适用于简单的 SoC，其中每个引脚用单个寄存器配置。
+
+## 设备树绑定
+
+### Pinctrl 控制器节点
+
+```dts
+pinctrl: pinctrl@11002000 {
+    compatible = "vendor,soc-pinctrl";
+    reg = <0x11002000 0x1000>;
+    #pinctrl-cells = <2>;  /* 功能, 配置 */
+    
+    /* 引脚组定义 */
+    uart0_pins: uart0 {
+        pins = <10 11>;  /* TX, RX 引脚 */
+        function = <1>;  /* UART 功能 */
+        drive-strength = <8>;  /* mA */
+        bias-pull-up;
+    };
+    
+    spi0_default: spi0_default {
+        pins = <20 21 22 23>;  /* CLK, MOSI, MISO, CS */
+        function = <2>;  /* SPI 功能 */
+        drive-strength = <12>;
+    };
+    
+    spi0_sleep: spi0_sleep {
+        pins = <20 21 22 23>;
+        function = <0>;  /* GPIO 功能 */
+        bias-pull-down;
+    };
+};
+```
+
+### 消费者设备
+
+```dts
+uart0: serial@11003000 {
+    compatible = "vendor,uart";
+    reg = <0x11003000 0x1000>;
+    
+    /* 引用引脚配置 */
+    pinctrl-names = "default";
+    pinctrl-0 = <&uart0_pins>;
+};
+
+spi0: spi@11004000 {
+    compatible = "vendor,spi";
+    reg = <0x11004000 0x1000>;
+    
+    /* 多状态引脚配置 */
+    pinctrl-names = "default", "sleep";
+    pinctrl-0 = <&spi0_default>;
+    pinctrl-1 = <&spi0_sleep>;
+};
+
+/* 具有 GPIO 引用的设备 */
+device@11005000 {
+    compatible = "vendor,device";
+    reg = <0x11005000 0x1000>;
+    
+    reset-gpios = <&gpio 10 GPIO_ACTIVE_LOW>;
+    enable-gpios = <&gpio 11 GPIO_ACTIVE_HIGH>;
+};
+```
+
+### 引脚配置属性
+
+常用的引脚配置属性：
+
+- `bias-disable`: 禁用上拉/下拉
+- `bias-pull-up`: 启用上拉
+- `bias-pull-down`: 启用下拉
+- `drive-strength`: 驱动强度（mA）
+- `input-enable`: 启用输入缓冲器
+- `output-high`: 设置输出为高电平
+- `output-low`: 设置输出为低电平
+
+## 应用层 API
+
+### 引脚配置 API
+
+#### rt_pin_ctrl_confs_apply
+
+按索引应用引脚配置。
+
+```c
+rt_err_t rt_pin_ctrl_confs_apply(struct rt_device *dev, int index);
+```
+
+**参数**:
+- `dev`: 设备指针
+- `index`: 设备树中的配置索引（0 表示 pinctrl-0）
+
+**返回值**:
+- `RT_EOK`: 成功
+- `-RT_EINVAL`: 无效参数
+- `-RT_EIO`: I/O 错误
+
+**示例**:
+```c
+/* 应用默认配置（pinctrl-0） */
+rt_pin_ctrl_confs_apply(spi_dev, 0);
+
+/* 应用休眠配置（pinctrl-1） */
+rt_pin_ctrl_confs_apply(spi_dev, 1);
+```
+
+#### rt_pin_ctrl_confs_apply_by_name
+
+按名称应用引脚配置。
+
+```c
+rt_err_t rt_pin_ctrl_confs_apply_by_name(struct rt_device *dev, const char *name);
+```
+
+**参数**:
+- `dev`: 设备指针
+- `name`: pinctrl-names 中的配置名称
+
+**返回值**:
+- `RT_EOK`: 成功
+- `-RT_EINVAL`: 无效参数或未找到名称
+- `-RT_EIO`: I/O 错误
+
+**示例**:
+```c
+/* 在设备初始化时应用默认引脚 */
+rt_pin_ctrl_confs_apply_by_name(dev, "default");
+
+/* 在挂起前切换到低功耗引脚 */
+rt_pin_ctrl_confs_apply_by_name(dev, "sleep");
+```
+
+#### rt_pin_ctrl_confs_lookup
+
+在设备树中查找引脚配置索引。
+
+```c
+int rt_pin_ctrl_confs_lookup(struct rt_device *dev, const char *name);
+```
+
+**参数**:
+- `dev`: 设备指针
+- `name`: pinctrl-names 中的配置名称
+
+**返回值**:
+- `>= 0`: 配置索引
+- `< 0`: 未找到错误
+
+**示例**:
+```c
+int idx = rt_pin_ctrl_confs_lookup(dev, "idle");
+if (idx >= 0) {
+    rt_pin_ctrl_confs_apply(dev, idx);
+}
+```
+
+### GPIO 辅助 API
+
+#### rt_pin_get_named_pin
+
+从设备树获取 GPIO 引脚编号。
+
+```c
+rt_ssize_t rt_pin_get_named_pin(struct rt_device *dev, 
+                                 const char *propname,
+                                 int index,
+                                 rt_uint8_t *out_mode,
+                                 rt_uint8_t *out_value);
+```
+
+**参数**:
+- `dev`: 设备指针
+- `propname`: GPIO 属性名称（如 "reset-gpios"）
+- `index`: GPIO 数组中的索引（对于单个 GPIO 为 0）
+- `out_mode`: 输出 GPIO 模式（可以为 NULL）
+- `out_value`: 输出 GPIO 值（可以为 NULL）
+
+**返回值**:
+- `>= 0`: GPIO 引脚编号
+- `< 0`: 错误
+
+**示例**:
+```c
+rt_uint8_t mode, value;
+rt_ssize_t pin = rt_pin_get_named_pin(dev, "reset-gpios", 0, &mode, &value);
+if (pin >= 0) {
+    /* 配置和使用 GPIO 引脚 */
+    rt_pin_mode(pin, mode);
+    rt_pin_write(pin, value);
+}
+```
+
+#### rt_pin_get_named_pin_count
+
+计算 GPIO 属性中的引脚数量。
+
+```c
+int rt_pin_get_named_pin_count(struct rt_device *dev, const char *propname);
+```
+
+**参数**:
+- `dev`: 设备指针
+- `propname`: GPIO 属性名称
+
+**返回值**:
+- `>= 0`: GPIO 引脚数量
+- `< 0`: 错误
+
+**示例**:
+```c
+int count = rt_pin_get_named_pin_count(dev, "gpios");
+for (int i = 0; i < count; i++) {
+    rt_ssize_t pin = rt_pin_get_named_pin(dev, "gpios", i, NULL, NULL);
+    /* 使用引脚 */
+}
+```
+
+## 使用示例
+
+### SPI 驱动的引脚管理示例
+
+```c
+#include <rtthread.h>
+#include <rtdevice.h>
+#include <drivers/pin.h>
+
+struct my_spi {
+    struct rt_spi_bus parent;
+    void *base;
+    struct rt_device *dev;
+    
+    /* GPIO 引脚 */
+    rt_ssize_t cs_pin;
+    rt_ssize_t reset_pin;
+};
+
+static rt_err_t my_spi_probe(struct rt_platform_device *pdev)
+{
+    struct my_spi *spi;
+    struct rt_device *dev = &pdev->parent;
+    rt_err_t ret;
+    
+    spi = rt_calloc(1, sizeof(*spi));
+    if (!spi)
+        return -RT_ENOMEM;
+    
+    spi->dev = dev;
+    
+    /* 应用默认引脚配置 */
+    ret = rt_pin_ctrl_confs_apply_by_name(dev, "default");
+    if (ret) {
+        rt_kprintf("Failed to apply default pinctrl: %d\n", ret);
+        goto err_free;
+    }
+    
+    /* 获取 GPIO 引脚 */
+    spi->cs_pin = rt_pin_get_named_pin(dev, "cs-gpios", 0, NULL, NULL);
+    if (spi->cs_pin < 0) {
+        rt_kprintf("Failed to get CS GPIO\n");
+        ret = spi->cs_pin;
+        goto err_free;
+    }
+    
+    spi->reset_pin = rt_pin_get_named_pin(dev, "reset-gpios", 0, NULL, NULL);
+    if (spi->reset_pin >= 0) {
+        /* 配置复位引脚 */
+        rt_pin_mode(spi->reset_pin, PIN_MODE_OUTPUT);
+        rt_pin_write(spi->reset_pin, PIN_HIGH);
+    }
+    
+    /* 配置 CS 引脚 */
+    rt_pin_mode(spi->cs_pin, PIN_MODE_OUTPUT);
+    rt_pin_write(spi->cs_pin, PIN_HIGH);
+    
+    /* 注册 SPI 总线 */
+    ret = rt_spi_bus_register(&spi->parent, "spi0", &spi_ops);
+    if (ret)
+        goto err_free;
+    
+    rt_platform_set_drvdata(pdev, spi);
+    
+    rt_kprintf("SPI driver probed successfully\n");
+    return RT_EOK;
+    
+err_free:
+    rt_free(spi);
+    return ret;
+}
+
+static rt_err_t my_spi_remove(struct rt_platform_device *pdev)
+{
+    struct my_spi *spi = rt_platform_get_drvdata(pdev);
+    
+    /* 释放 GPIO 引脚 */
+    if (spi->reset_pin >= 0) {
+        rt_pin_write(spi->reset_pin, PIN_LOW);
+    }
+    
+    rt_spi_bus_unregister(&spi->parent);
+    rt_free(spi);
+    
+    return RT_EOK;
+}
+
+/* 电源管理钩子 */
+static int my_spi_suspend(const struct rt_device *dev, rt_uint8_t mode)
+{
+    /* 切换到休眠引脚配置 */
+    return rt_pin_ctrl_confs_apply_by_name((struct rt_device *)dev, "sleep");
+}
+
+static void my_spi_resume(const struct rt_device *dev, rt_uint8_t mode)
+{
+    /* 恢复默认引脚配置 */
+    rt_pin_ctrl_confs_apply_by_name((struct rt_device *)dev, "default");
+}
+
+static const struct rt_device_ops spi_ops = {
+    .suspend = my_spi_suspend,
+    .resume = my_spi_resume,
+};
+
+static const struct rt_ofw_node_id my_spi_ids[] = {
+    { .compatible = "vendor,my-spi" },
+    { /* sentinel */ }
+};
+
+static struct rt_platform_driver my_spi_driver = {
+    .name = "my-spi",
+    .ids = my_spi_ids,
+    .probe = my_spi_probe,
+    .remove = my_spi_remove,
+};
+
+static int my_spi_drv_register(void)
+{
+    rt_platform_driver_register(&my_spi_driver);
+    return 0;
+}
+INIT_SUBSYS_EXPORT(my_spi_drv_register);
+```
+
+## 驱动实现指南
+
+### Simple Pinctrl 驱动示例
+
+```c
+#include <rtthread.h>
+#include <rtdevice.h>
+
+struct simple_pinctrl {
+    struct rt_device parent;
+    void *base;
+    rt_size_t ngroups;
+};
+
+static rt_err_t simple_pinctrl_set_mux(struct rt_pinctrl *ctrl,
+                                        rt_uint32_t group,
+                                        rt_uint32_t function)
+{
+    struct simple_pinctrl *pinctrl = rt_container_of(ctrl, struct simple_pinctrl, parent);
+    void *reg = pinctrl->base + (group * 4);
+    
+    /* 设置功能复用 */
+    rt_uint32_t val = readl(reg);
+    val &= ~0xFF;
+    val |= function & 0xFF;
+    writel(val, reg);
+    
+    return RT_EOK;
+}
+
+static rt_err_t simple_pinctrl_set_config(struct rt_pinctrl *ctrl,
+                                           rt_uint32_t group,
+                                           rt_ubase_t config)
+{
+    struct simple_pinctrl *pinctrl = rt_container_of(ctrl, struct simple_pinctrl, parent);
+    void *reg = pinctrl->base + (group * 4);
+    rt_uint32_t param = RT_PINCTRL_CONFIG_PARAM(config);
+    rt_uint32_t arg = RT_PINCTRL_CONFIG_ARG(config);
+    rt_uint32_t val;
+    
+    val = readl(reg);
+    
+    switch (param) {
+    case PIN_CONFIG_BIAS_DISABLE:
+        val &= ~(BIT(8) | BIT(9));  /* 清除上拉/下拉 */
+        break;
+        
+    case PIN_CONFIG_BIAS_PULL_UP:
+        val |= BIT(8);
+        val &= ~BIT(9);
+        break;
+        
+    case PIN_CONFIG_BIAS_PULL_DOWN:
+        val |= BIT(9);
+        val &= ~BIT(8);
+        break;
+        
+    case PIN_CONFIG_DRIVE_STRENGTH:
+        val &= ~(0xF << 16);
+        val |= (arg & 0xF) << 16;
+        break;
+        
+    default:
+        return -RT_EINVAL;
+    }
+    
+    writel(val, reg);
+    return RT_EOK;
+}
+
+static const struct rt_pinctrl_ops simple_pinctrl_ops = {
+    .set_mux = simple_pinctrl_set_mux,
+    .set_config = simple_pinctrl_set_config,
+};
+
+static rt_err_t simple_pinctrl_probe(struct rt_platform_device *pdev)
+{
+    struct simple_pinctrl *pinctrl;
+    rt_err_t ret;
+    
+    pinctrl = rt_calloc(1, sizeof(*pinctrl));
+    if (!pinctrl)
+        return -RT_ENOMEM;
+    
+    /* 映射寄存器 */
+    pinctrl->base = rt_dm_dev_iomap(&pdev->parent, 0);
+    if (!pinctrl->base) {
+        ret = -RT_EIO;
+        goto err_free;
+    }
+    
+    /* 获取引脚组数量 */
+    rt_dm_dev_prop_read_u32(&pdev->parent, "pinctrl-groups", &pinctrl->ngroups);
+    
+    /* 注册 pinctrl 设备 */
+    pinctrl->parent.ops = &simple_pinctrl_ops;
+    ret = rt_pinctrl_register(&pinctrl->parent, &pdev->parent);
+    if (ret)
+        goto err_unmap;
+    
+    rt_platform_set_drvdata(pdev, pinctrl);
+    
+    return RT_EOK;
+    
+err_unmap:
+    rt_dm_dev_iounmap(&pdev->parent, pinctrl->base);
+err_free:
+    rt_free(pinctrl);
+    return ret;
+}
+
+static const struct rt_ofw_node_id simple_pinctrl_ids[] = {
+    { .compatible = "simple-pinctrl" },
+    { /* sentinel */ }
+};
+
+static struct rt_platform_driver simple_pinctrl_driver = {
+    .name = "simple-pinctrl",
+    .ids = simple_pinctrl_ids,
+    .probe = simple_pinctrl_probe,
+};
+```
+
+## 最佳实践
+
+### 消费者最佳实践
+
+1. **始终应用默认配置**
+   ```c
+   rt_pin_ctrl_confs_apply_by_name(dev, "default");
+   ```
+
+2. **使用命名状态进行电源管理**
+   ```c
+   /* 挂起 */
+   rt_pin_ctrl_confs_apply_by_name(dev, "sleep");
+   
+   /* 恢复 */
+   rt_pin_ctrl_confs_apply_by_name(dev, "default");
+   ```
+
+3. **检查 GPIO 可用性**
+   ```c
+   rt_ssize_t pin = rt_pin_get_named_pin(dev, "reset-gpios", 0, NULL, NULL);
+   if (pin >= 0) {
+       /* GPIO 可用 */
+   }
+   ```
+
+4. **使用 pinctrl 进行专用功能，使用 GPIO 进行 GPIO**
+   - Pinctrl：功能复用、电气配置
+   - GPIO：运行时 GPIO 操作
+
+### 提供者最佳实践
+
+1. **支持所有相关的配置参数**
+   - 上拉/下拉
+   - 驱动强度
+   - 输入使能
+   - 其他特定于硬件的参数
+
+2. **验证引脚组索引**
+   ```c
+   if (group >= pinctrl->ngroups)
+       return -RT_EINVAL;
+   ```
+
+3. **实现原子配置更新**
+   - 读取-修改-写入序列
+   - 考虑寄存器锁定
+
+## 故障排除
+
+### 引脚配置失败
+
+**症状**: rt_pin_ctrl_confs_apply 返回错误
+
+**可能原因**:
+1. 设备树中的 pinctrl 引用不正确
+2. Pinctrl 驱动未加载
+3. 引脚组索引超出范围
+
+**解决方案**:
+```c
+/* 检查 pinctrl 引用 */
+int idx = rt_pin_ctrl_confs_lookup(dev, "default");
+if (idx < 0) {
+    rt_kprintf("Pinctrl 'default' not found in DT\n");
+}
+
+/* 验证 pinctrl 驱动 */
+if (!dev->pinctrl) {
+    rt_kprintf("No pinctrl controller available\n");
+}
+```
+
+### GPIO 与 Pinctrl 冲突
+
+**症状**: GPIO 操作不起作用或引脚不响应
+
+**可能原因**:
+- 引脚复用为外设功能而不是 GPIO
+- 冲突的引脚配置
+
+**解决方案**:
+```c
+/* 对于 GPIO 使用，确保引脚复用为 GPIO 功能 */
+/* 在设备树中或通过 pinctrl 驱动程序 */
+```
+
+### 电源管理状态切换
+
+**症状**: 从休眠恢复后外设不工作
+
+**可能原因**:
+- 忘记恢复默认引脚状态
+- 引脚状态切换顺序不正确
+
+**解决方案**:
+```c
+/* 在恢复时始终恢复默认状态 */
+static void my_device_resume(const struct rt_device *dev, rt_uint8_t mode)
+{
+    rt_pin_ctrl_confs_apply_by_name((struct rt_device *)dev, "default");
+    
+    /* 然后重新初始化硬件 */
+}
+```
+
+## 相关模块
+
+- **GPIO 框架**: 运行时 GPIO 操作
+- **OFW (设备树)**: 设备树解析
+- **电源管理**: 引脚状态用于低功耗模式
+- **SCMI**: 固件引脚控制
+
+## 参考
+
+- `components/drivers/include/drivers/pin.h`
+- `components/drivers/core/pinctrl.c`
+- Linux Pinctrl 子系统文档