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add 06_Pinctrl/06_client端使用pinctrl过程的情景分析_基于IMX6ULL, 06_client端使用pinctrl过程的情景分析_基于STM32MP157
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## client端使用pinctrl过程的情景分析_基于IMX6ULL
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参考资料:
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* Linux 5.x内核
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* Documentation\devicetree\bindings\pinctrl\pinctrl-bindings.txt
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* arch/arm/boot/dts/stm32mp151.dtsi
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* arch/arm/boot/dts/stm32mp157-100ask-pinctrl.dtsi
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* arch/arm/boot/dts/stm32mp15xx-100ask.dtsi
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* drivers\pinctrl\stm32\pinctrl-stm32mp157.c
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* drivers\pinctrl\stm32\pinctrl-stm32.c
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* Linux 4.x内核
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* Documentation\pinctrl.txt
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* Documentation\devicetree\bindings\pinctrl\pinctrl-bindings.txt
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* arch/arm/boot/dts/imx6ull-14x14-evk.dts
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* arch/arm/boot/dts/100ask_imx6ull-14x14.dts
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* drivers\pinctrl\freescale\pinctrl-imx6ul.c
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* drivers\pinctrl\freescale\pinctrl-imx.c
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### 1. 回顾client的数据结构
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在设备树中,使用pinctrl时格式如下:
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设备节点要么被转换为platform_device,或者其他结构体(比如i2c_client),但是里面都会有一个device结构体,比如:
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#### 1.1 dev_pin_info
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每个device结构体里都有一个dev_pin_info结构体,用来保存设备的pinctrl信息:
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#### 1.2 pinctrl
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假设芯片上有多个pin controller,那么这个设备使用哪个pin controller?
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这需要通过设备树来确定:
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* 分析设备树,找到pin controller
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* 对于每个状态,比如default、init,去分析pin controller中的设备树节点
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* 使用pin controller的pinctrl_ops.dt_node_to_map来处理设备树的pinctrl节点信息,得到一系列的pinctrl_map
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* 这些pinctrl_map放在pinctrl.dt_maps链表中
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* 每个pinctrl_map都被转换为pinctrl_setting,放在对应的pinctrl_state.settings链表中
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#### 1.3 pinctrl_map和pinctrl_setting
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设备引用pin controller中的某个节点时,这个节点会被转换为一些列的pinctrl_map:
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* 转换为多少个pinctrl_map,完全由具体的驱动决定
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* 每个pinctrl_map,又被转换为一个pinctrl_setting
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* 举例,设备节点里有:`pinctrl-0 = <&state_0_node_a>`
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* pinctrl-0对应一个状态,会得到一个pinctrl_state
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* state_0_node_a节点被解析为一系列的pinctrl_map
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* 这一系列的pinctrl_map被转换为一系列的pinctrl_setting
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* 这些pinctrl_setting被放入pinctrl_state的settings链表
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### 2. client节点的pinctrl构造过程
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#### 2.1 函数调用
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```shell
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really_probe
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pinctrl_bind_pins
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dev->pins = devm_kzalloc(dev, sizeof(*(dev->pins)), GFP_KERNEL);
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dev->pins->p = devm_pinctrl_get(dev);
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pinctrl_get
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create_pinctrl(dev);
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ret = pinctrl_dt_to_map(p);
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for_each_maps(maps_node, i, map) {
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ret = add_setting(p, map);
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}
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dev->pins->default_state = pinctrl_lookup_state(dev->pins->p,
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PINCTRL_STATE_DEFAULT);
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```
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#### 2.2 情景分析
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##### 1. 设备树转换为pinctrl_map
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##### 2. pinctrl_map转换为pinctrl_setting
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### 3. 切换state情景分析
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#### 3.1 函数调用过程
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涉及pinctrl子系统的其他2个作用:引脚复用、引脚配置
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```shell
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really_probe
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pinctrl_bind_pins
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pinctrl_select_state
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/* Apply all the settings for the new state */
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list_for_each_entry(setting, &state->settings, node) {
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switch (setting->type) {
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case PIN_MAP_TYPE_MUX_GROUP:
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ret = pinmux_enable_setting(setting);
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ret = ops->set_mux(...);
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break;
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case PIN_MAP_TYPE_CONFIGS_PIN:
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case PIN_MAP_TYPE_CONFIGS_GROUP:
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ret = pinconf_apply_setting(setting);
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ret = ops->pin_config_group_set(...);
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break;
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default:
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ret = -EINVAL;
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break;
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}
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```
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#### 3.2 情景分析
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#####
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Binary file not shown.
11
README.md
11
README.md
@@ -196,6 +196,17 @@ git clone https://e.coding.net/weidongshan/linux/doc_and_source_for_drivers.git
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05_Pincontroller构造过程情景分析_基于STM32MP157
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05_Pincontroller构造过程情景分析_基于STM32MP157
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```
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```
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* 2021.05.13 发布"Pinctrl子系统":
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```shell
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06_client端使用pinctrl过程的情景分析_基于IMX6ULL
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06_client端使用pinctrl过程的情景分析_基于STM32MP157
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```
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@@ -0,0 +1,136 @@
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## client端使用pinctrl过程的情景分析_基于STM32MP157
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参考资料:
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* Linux 5.x内核
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* Documentation\devicetree\bindings\pinctrl\pinctrl-bindings.txt
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* arch/arm/boot/dts/stm32mp151.dtsi
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* arch/arm/boot/dts/stm32mp157-100ask-pinctrl.dtsi
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* arch/arm/boot/dts/stm32mp15xx-100ask.dtsi
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* drivers\pinctrl\stm32\pinctrl-stm32mp157.c
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* drivers\pinctrl\stm32\pinctrl-stm32.c
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* Linux 4.x内核
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* Documentation\pinctrl.txt
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* Documentation\devicetree\bindings\pinctrl\pinctrl-bindings.txt
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* arch/arm/boot/dts/imx6ull-14x14-evk.dts
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* arch/arm/boot/dts/100ask_imx6ull-14x14.dts
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* drivers\pinctrl\freescale\pinctrl-imx6ul.c
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* drivers\pinctrl\freescale\pinctrl-imx.c
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### 1. 回顾client的数据结构
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||||||
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在设备树中,使用pinctrl时格式如下:
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||||||
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设备节点要么被转换为platform_device,或者其他结构体(比如i2c_client),但是里面都会有一个device结构体,比如:
|
||||||
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||||||
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||||||
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#### 1.1 dev_pin_info
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||||||
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||||||
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每个device结构体里都有一个dev_pin_info结构体,用来保存设备的pinctrl信息:
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||||||
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|
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|

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#### 1.2 pinctrl
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||||||
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假设芯片上有多个pin controller,那么这个设备使用哪个pin controller?
|
||||||
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|
||||||
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这需要通过设备树来确定:
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||||||
|
|
||||||
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* 分析设备树,找到pin controller
|
||||||
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* 对于每个状态,比如default、init,去分析pin controller中的设备树节点
|
||||||
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* 使用pin controller的pinctrl_ops.dt_node_to_map来处理设备树的pinctrl节点信息,得到一系列的pinctrl_map
|
||||||
|
* 这些pinctrl_map放在pinctrl.dt_maps链表中
|
||||||
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* 每个pinctrl_map都被转换为pinctrl_setting,放在对应的pinctrl_state.settings链表中
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||||||
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||||||
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#### 1.3 pinctrl_map和pinctrl_setting
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||||||
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设备引用pin controller中的某个节点时,这个节点会被转换为一些列的pinctrl_map:
|
||||||
|
|
||||||
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* 转换为多少个pinctrl_map,完全由具体的驱动决定
|
||||||
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* 每个pinctrl_map,又被转换为一个pinctrl_setting
|
||||||
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* 举例,设备节点里有:`pinctrl-0 = <&state_0_node_a>`
|
||||||
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* pinctrl-0对应一个状态,会得到一个pinctrl_state
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||||||
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* state_0_node_a节点被解析为一系列的pinctrl_map
|
||||||
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* 这一系列的pinctrl_map被转换为一系列的pinctrl_setting
|
||||||
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* 这些pinctrl_setting被放入pinctrl_state的settings链表
|
||||||
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|
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|

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### 2. client节点的pinctrl构造过程
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#### 2.1 函数调用
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|
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```shell
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really_probe
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pinctrl_bind_pins
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dev->pins = devm_kzalloc(dev, sizeof(*(dev->pins)), GFP_KERNEL);
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dev->pins->p = devm_pinctrl_get(dev);
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pinctrl_get
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create_pinctrl(dev);
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ret = pinctrl_dt_to_map(p);
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for_each_maps(maps_node, i, map) {
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ret = add_setting(p, map);
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}
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dev->pins->default_state = pinctrl_lookup_state(dev->pins->p,
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PINCTRL_STATE_DEFAULT);
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```
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#### 2.2 情景分析
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||||||
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##### 1. 设备树转换为pinctrl_map
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||||||
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|
||||||
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##### 2. pinctrl_map转换为pinctrl_setting
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### 3. 切换state情景分析
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#### 3.1 函数调用过程
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||||||
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|
||||||
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涉及pinctrl子系统的其他2个作用:引脚复用、引脚配置
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||||||
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```shell
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really_probe
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pinctrl_bind_pins
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pinctrl_select_state
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/* Apply all the settings for the new state */
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list_for_each_entry(setting, &state->settings, node) {
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switch (setting->type) {
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case PIN_MAP_TYPE_MUX_GROUP:
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ret = pinmux_enable_setting(setting);
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ret = ops->set_mux(...);
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break;
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case PIN_MAP_TYPE_CONFIGS_PIN:
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case PIN_MAP_TYPE_CONFIGS_GROUP:
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ret = pinconf_apply_setting(setting);
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ret = ops->pin_config_group_set(...);
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break;
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default:
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ret = -EINVAL;
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break;
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}
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```
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#### 3.2 情景分析
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