stm32: Add USB support for STM32L1 MCUs.

Signed-off-by: Yuuki NAGAO <wf.yn386@gmail.com>

ports/stm32/Makefile

@@ -404,7 +404,7 @@ HAL_SRC_C += $(addprefix $(STM32LIB_HAL_BASE)/Src/stm32$(MCU_SERIES)xx_,\
 	ll_utils.c \
 	)
 
-ifeq ($(MCU_SERIES),$(filter $(MCU_SERIES),f4 f7 g0 g4 h5 h7 l0 l4 wb))
+ifeq ($(MCU_SERIES),$(filter $(MCU_SERIES),f4 f7 g0 g4 h5 h7 l0 l1 l4 wb))
 HAL_SRC_C += $(addprefix $(STM32LIB_HAL_BASE)/Src/stm32$(MCU_SERIES)xx_,\
 	hal_pcd.c \
 	hal_pcd_ex.c \

ports/stm32/boards/NUCLEO_L152RE/mpconfigboard.h

@@ -7,6 +7,7 @@
 #define MICROPY_HW_RTC_USE_LSE      (1)
 #define MICROPY_HW_ENABLE_SERVO     (1)
 #define MICROPY_HW_ENABLE_DAC       (1)
+#define MICROPY_HW_ENABLE_USB       (0)
 
 // HSE is 8MHz, HSI is 16MHz CPU freq set to 32MHz
 // Default source for the clock is HSI.
@@ -72,3 +73,11 @@
 #define MICROPY_HW_LED_OFF(pin)     (mp_hal_pin_low(pin))
 
 #define MICROPY_HW_FLASH_LATENCY FLASH_LATENCY_1
+
+// USB config
+#if MICROPY_HW_ENABLE_USB
+#if MICROPY_HW_CLK_USE_HSI
+#error STM32L152RE cannot use USB feature with HSI clock. Use HSE.
+#endif
+#define MICROPY_HW_USB_FS (1)
+#endif

ports/stm32/boards/stm32l1xx_hal_conf_base.h

@@ -26,6 +26,9 @@
 #ifndef MICROPY_INCLUDED_STM32L1XX_HAL_CONF_BASE_H
 #define MICROPY_INCLUDED_STM32L1XX_HAL_CONF_BASE_H
 
+// Needs to be defined before ll_usb.h is included
+#define HAL_PCD_MODULE_ENABLED
+
 // Include various HAL modules for convenience
 #include "stm32l1xx_hal_rcc.h"
 #include "stm32l1xx_hal_gpio.h"
@@ -38,6 +41,7 @@
 #include "stm32l1xx_hal_flash.h"
 #include "stm32l1xx_hal_i2c.h"
 #include "stm32l1xx_hal_iwdg.h"
+#include "stm32l1xx_hal_pcd.h"
 #include "stm32l1xx_hal_pwr.h"
 #include "stm32l1xx_hal_rtc.h"
 #include "stm32l1xx_hal_spi.h"
@@ -50,6 +54,7 @@
 #include "stm32l1xx_ll_pwr.h"
 #include "stm32l1xx_ll_rtc.h"
 #include "stm32l1xx_ll_usart.h"
+#include "stm32l1xx_ll_usb.h"
 
 // Enable various HAL modules
 #define HAL_MODULE_ENABLED

ports/stm32/mpconfigboard_common.h

@@ -586,7 +586,7 @@
 // Whether the USB peripheral is device-only, or multiple OTG
 // For STM32G0 and STM32H5 the USB peripheral supports device and host mode,
 // but otherwise acts like a non-multi-OTG peripheral.
-#if defined(STM32G0) || defined(STM32G4) || defined(STM32H5) || defined(STM32L0) || defined(STM32L432xx) || defined(STM32WB)
+#if defined(STM32G0) || defined(STM32G4) || defined(STM32H5) || defined(STM32L0) || defined(STM32L1) || defined(STM32L432xx) || defined(STM32WB)
 #define MICROPY_HW_USB_IS_MULTI_OTG (0)
 #else
 #define MICROPY_HW_USB_IS_MULTI_OTG (1)

ports/stm32/powerctrlboot.c

@@ -348,6 +348,8 @@ void SystemClock_Config(void) {
 #elif defined(STM32L1)
 
 void SystemClock_Config(void) {
+    // Enable SYSCFG clock
+    __HAL_RCC_SYSCFG_CLK_ENABLE();
     // Enable power control peripheral
     __HAL_RCC_PWR_CLK_ENABLE();
 
@@ -388,25 +390,6 @@ void SystemClock_Config(void) {
     SystemCoreClockUpdate();
     powerctrl_config_systick();
 
-    #if MICROPY_HW_ENABLE_USB
-    // Enable the 48MHz internal oscillator
-    RCC->CRRCR |= RCC_CRRCR_HSI48ON;
-    RCC->APB2ENR |= RCC_APB2ENR_SYSCFGEN;
-    SYSCFG->CFGR3 |= SYSCFG_CFGR3_ENREF_HSI48;
-    while (!(RCC->CRRCR & RCC_CRRCR_HSI48RDY)) {
-        // Wait for HSI48 to be ready
-    }
-
-    // Select RC48 as HSI48 for USB and RNG
-    RCC->CCIPR |= RCC_CCIPR_HSI48SEL;
-
-    // Synchronise HSI48 with 1kHz USB SoF
-    __HAL_RCC_CRS_CLK_ENABLE();
-    CRS->CR = 0x20 << CRS_CR_TRIM_Pos;
-    CRS->CFGR = 2 << CRS_CFGR_SYNCSRC_Pos | 0x22 << CRS_CFGR_FELIM_Pos
-        | __HAL_RCC_CRS_RELOADVALUE_CALCULATE(48000000, 1000) << CRS_CFGR_RELOAD_Pos;
-    #endif
-
     // Disable the Debug Module in low-power mode due to prevent
     // unexpected HardFault after __WFI().
     #if !defined(NDEBUG)

ports/stm32/stm32_it.c

@@ -320,7 +320,7 @@ void USB_IRQHandler(void) {
 }
 #endif
 
-#elif defined(STM32G4) || defined(STM32WB)
+#elif defined(STM32G4) || defined(STM32L1) || defined(STM32WB)
 
 #if MICROPY_HW_USB_FS
 void USB_LP_IRQHandler(void) {

ports/stm32/usb.c

@@ -59,7 +59,7 @@
 #endif
 
 // Maximum number of endpoints (excluding EP0)
-#if defined(STM32G0) || defined(STM32G4) || defined(STM32H5) || defined(STM32L0) || defined(STM32WB)
+#if defined(STM32G0) || defined(STM32G4) || defined(STM32H5) || defined(STM32L0) || defined(STM32L1) || defined(STM32WB)
 #define MAX_ENDPOINT(dev_id) (7)
 #elif defined(STM32L4)
 #define MAX_ENDPOINT(dev_id) (5)

ports/stm32/usbd_conf.c

@@ -75,6 +75,16 @@ void HAL_PCD_MspInit(PCD_HandleTypeDef *hpcd) {
         mp_hal_pin_config(pin_A12, MP_HAL_PIN_MODE_ANALOG, MP_HAL_PIN_PULL_NONE, 0);
         mp_hal_pin_config_speed(pin_A12, GPIO_SPEED_FREQ_VERY_HIGH);
 
+        #elif defined(STM32L1)
+
+        // STM32L1 doesn't have an alternate function for USB.
+        // To be disconnected from all peripherals, put in input mode.
+
+        mp_hal_pin_config(pin_A11, MP_HAL_PIN_MODE_INPUT, MP_HAL_PIN_PULL_NONE, 0);
+        mp_hal_pin_config_speed(pin_A11, GPIO_SPEED_FREQ_VERY_HIGH);
+        mp_hal_pin_config(pin_A12, MP_HAL_PIN_MODE_INPUT, MP_HAL_PIN_PULL_NONE, 0);
+        mp_hal_pin_config_speed(pin_A12, GPIO_SPEED_FREQ_VERY_HIGH);
+
         #else
 
         // Other MCUs have an alternate function for GPIO's to be in USB mode.
@@ -149,7 +159,7 @@ void HAL_PCD_MspInit(PCD_HandleTypeDef *hpcd) {
         #elif defined(STM32L432xx)
         NVIC_SetPriority(USB_FS_IRQn, IRQ_PRI_OTG_FS);
         HAL_NVIC_EnableIRQ(USB_FS_IRQn);
-        #elif defined(STM32G4) || defined(STM32WB)
+        #elif defined(STM32G4) || defined(STM32L1) || defined(STM32WB)
         NVIC_SetPriority(USB_LP_IRQn, IRQ_PRI_OTG_FS);
         HAL_NVIC_EnableIRQ(USB_LP_IRQn);
         #else
@@ -708,6 +718,24 @@ void USBD_LL_Delay(uint32_t Delay) {
     HAL_Delay(Delay);
 }
 
+#if defined(STM32L1)
+/**
+  * @brief Software Device Connection
+  * @param hpcd: PCD handle
+  * @param state: Connection state (0: disconnected / 1: connected)
+  * @retval None
+  */
+void HAL_PCDEx_SetConnectionState(PCD_HandleTypeDef *hpcd, uint8_t state) {
+    if (state == 1) {
+        /*  DP Pull-Down is Internal */
+        __HAL_SYSCFG_USBPULLUP_ENABLE();
+    } else {
+        /*  DP Pull-Down is Internal */
+        __HAL_SYSCFG_USBPULLUP_DISABLE();
+    }
+}
+#endif
+
 #endif // MICROPY_HW_USB_FS || MICROPY_HW_USB_HS
 
 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/