Merge pull request #4634 from nvlsianpu/bugfix/issue_4357_I2C_SPI_simultaneously

 Fix the issue #4357: NRF52 doesn't support simultaneous use of I2C and SPI.

Author: 0xc0170

targets/TARGET_NORDIC/TARGET_NRF5/i2c_api.c

@@ -290,7 +290,9 @@ static void twi_clear_bus(twi_info_t *twi_info)
 
 void i2c_init(i2c_t *obj, PinName sda, PinName scl)
 {
+    ret_code_t ret;
     int i;
+
     for (i = 0; i < TWI_COUNT; ++i) {
         if (m_twi_info[i].initialized &&
             m_twi_info[i].pselsda == (uint32_t)sda &&
@@ -304,6 +306,13 @@ void i2c_init(i2c_t *obj, PinName sda, PinName scl)
 
     for (i = 0; i < TWI_COUNT; ++i) {
         if (!m_twi_info[i].initialized) {
+            ret = nrf_drv_common_per_res_acquire(m_twi_instances[i],
+                    m_twi_irq_handlers[i]);
+
+            if (ret != NRF_SUCCESS) {
+                continue; /* the hw resource is busy - test another one */
+            }
+
             TWI_IDX(obj) = i;
 
             twi_info_t *twi_info = TWI_INFO(obj);
@@ -324,8 +333,6 @@ void i2c_init(i2c_t *obj, PinName sda, PinName scl)
             i2c_reset(obj);
 
 #if DEVICE_I2C_ASYNCH
-            nrf_drv_common_per_res_acquire(m_twi_instances[i],
-                m_twi_irq_handlers[i]);
             NVIC_SetVector(twi_handlers[i].IRQn, twi_handlers[i].vector);
             nrf_drv_common_irq_enable(twi_handlers[i].IRQn, TWI_IRQ_PRIORITY);
 #endif

targets/TARGET_NORDIC/TARGET_NRF5/spi_api.c

@@ -277,9 +277,11 @@ void spi_init(spi_t *obj,
         }
     }
 
-    for (i = 0; i < SPI_COUNT; ++i) {
+    for (i = SPI_COUNT - 1; i >= 0; i--) {
         spi_info_t *p_spi_info = &m_spi_info[i];
+
         if (!p_spi_info->initialized) {
+
             p_spi_info->sck_pin   = (uint8_t)sclk;
             p_spi_info->mosi_pin  = (mosi != NC) ?
                 (uint8_t)mosi : NRF_DRV_SPI_PIN_NOT_USED;
@@ -290,8 +292,6 @@ void spi_init(spi_t *obj,
             p_spi_info->spi_mode  = (uint8_t)NRF_DRV_SPI_MODE_0;
             p_spi_info->frequency = NRF_DRV_SPI_FREQ_1M;
 
-            NVIC_SetVector(spi_handler_desc[i].IRQn, spi_handler_desc[i].vector);
-
             // By default each SPI instance is initialized to work as a master.
             // Should the slave mode be used, the instance will be reconfigured
             // appropriately in 'spi_format'.
@@ -305,11 +305,11 @@ void spi_init(spi_t *obj,
                 p_spi_info->initialized = true;
                 p_spi_info->master      = true;
                 p_spi_info->flag.busy   = false;
-            #if DEVICE_SPI_ASYNCH
+#if DEVICE_SPI_ASYNCH
                 p_spi_info->handler     = 0;
-            #endif
+#endif
                 SPI_IDX(obj) = i;
-
+                NVIC_SetVector(spi_handler_desc[i].IRQn, spi_handler_desc[i].vector);
                 return;
             }
         }