feat(MiscDrivers): Add Ability to Set Pushbutton Polarity (#1166)

Co-authored-by: Woo <[email protected]>
Co-authored-by: Sihyung Woo <[email protected]>

Examples/MAX32690/Bluetooth/Bootloader/README.md

@@ -9,7 +9,7 @@ the main flash section is erased and replaced with the update image. If no valid
 is identified, the Bootloader will boot the exiting image in the main flash space.
 
 __0x10000000__: Bootloader  
-__0x10004000__: Main flash space  
+__0x10008000__: Main flash space  
 __0x10300000__: Update flash space
 
 ## Software

Examples/MAX32690/Bluetooth/Bootloader/boot_lower.S

@@ -31,7 +31,7 @@
 /* Boot from the lower flash array */
 Boot_Lower:
 
-    ldr     r0,=0x10004000      /* Address for main flash image */
+    ldr     r0,=0x10008000      /* Address for main flash image */
     ldr     r1,=0xE000ED08      /* Address for SCB_VTOR_REG */
 
     /* First 32-bit word in image is initial stack pointer */

Examples/MAX32690/Bluetooth/Bootloader/bootloader.ld

@@ -18,15 +18,17 @@
  *
  ******************************************************************************/
 
-BOOTLOADER_ORIGIN = 0x10000000;
-BOOTLOADER_LEN = 0x4000;
-FLASH_SECTION_LEN = 0x40000 - BOOTLOADER_LEN;
+/* Note: Flash 0 page size is 16KB (0x4000). Flash 1 page size is 8KB (0x2000) */
+BOOTLOADER_ORIGIN = 0x10000000;                         /* Bootloader resides in Flash 0 */
+BOOTLOADER_LEN = 0x8000;                                /* 2 Flash 0 pages length (total 32KB) */
+FLASH0_SECTION_LEN = 0x300000 - BOOTLOADER_LEN;         /* 3MB - 2 pages (16KB/page) */
+FLASH1_SECTION_LEN = 0x40000;                           /* 256KB */
 FLASH0_ORIGIN = BOOTLOADER_ORIGIN + BOOTLOADER_LEN;
 
 MEMORY {
     FLASH      (rx) : ORIGIN = BOOTLOADER_ORIGIN,   LENGTH = BOOTLOADER_LEN
-    FLASH0     (rx) : ORIGIN = FLASH0_ORIGIN,       LENGTH = FLASH_SECTION_LEN
-    FLASH1     (rx) : ORIGIN = 0x10300000,          LENGTH = FLASH_SECTION_LEN
+    FLASH0     (rx) : ORIGIN = FLASH0_ORIGIN,       LENGTH = FLASH0_SECTION_LEN
+    FLASH1     (rx) : ORIGIN = 0x10300000,          LENGTH = FLASH1_SECTION_LEN
     SRAM      (rwx) : ORIGIN = 0x20000000,          LENGTH = 0x20000
 }
 
@@ -50,14 +52,14 @@ SECTIONS {
     .flash0 (NOLOAD) :
     {
         _flash0 = ALIGN(., 4); 
-        . = . + FLASH_SECTION_LEN;
+        . = . + FLASH0_SECTION_LEN;
         _eflash0 = ALIGN(., 4);
     } > FLASH0
 
     .flash1 (NOLOAD) :
     {
         _flash1 = ALIGN(., 4); 
-        . = . + FLASH_SECTION_LEN;
+        . = . + FLASH1_SECTION_LEN;
         _eflash1 = ALIGN(., 4);
     } > FLASH1
 

Libraries/Boards/MAX32690/APARD/Source/board.c

@@ -146,6 +146,8 @@ int Board_Init(void)
         return err;
     }
 
+    PB_Set_Polarity(0, PB_POLARITY_HIGH);
+
     if ((err = LED_Init()) != E_NO_ERROR) {
         MXC_ASSERT_FAIL();
         return err;

Libraries/MiscDrivers/PushButton/pb.c

@@ -19,11 +19,15 @@
  ******************************************************************************/
 
 #include <stddef.h>
+#include <stdlib.h>
 #include "board.h"
 #include "mxc_device.h"
 #include "mxc_assert.h"
 #include "pb.h"
 
+// State array for holding PB polarity settings
+static pb_polarity_t *g_pb_polarity = NULL;
+
 /******************************************************************************/
 int PB_Init(void)
 {
@@ -37,9 +41,30 @@ int PB_Init(void)
         }
     }
 
+    if (g_pb_polarity == NULL) {
+        g_pb_polarity = malloc(num_pbs * sizeof(pb_polarity_t));
+        // Note we have to use malloc here because we decided to make "num_pbs" a
+        // const variable instead of a compiler definition...
+    }
+
+    for (unsigned int i = 0; i < num_pbs; i++) {
+        g_pb_polarity[i] = PB_POLARITY_LOW;
+    }
+
     return retval;
 }
 
+/******************************************************************************/
+int PB_Set_Polarity(unsigned int pb, pb_polarity_t polarity)
+{
+    if (pb >= num_pbs) {
+        return E_BAD_PARAM;
+    }
+
+    g_pb_polarity[pb] = polarity;
+    return E_NO_ERROR;
+}
+
 /******************************************************************************/
 int PB_RegisterCallback(unsigned int pb, pb_callback callback)
 {
@@ -52,7 +77,11 @@ int PB_RegisterCallback(unsigned int pb, pb_callback callback)
         MXC_GPIO_RegisterCallback(&pb_pin[pb], callback, (void *)pb);
 
         // Configure and enable interrupt
-        MXC_GPIO_IntConfig(&pb_pin[pb], MXC_GPIO_INT_FALLING);
+        mxc_gpio_int_pol_t interrupt_polarity = MXC_GPIO_INT_FALLING;
+        if (g_pb_polarity[pb] == PB_POLARITY_HIGH) {
+            interrupt_polarity = MXC_GPIO_INT_RISING;
+        }
+        MXC_GPIO_IntConfig(&pb_pin[pb], interrupt_polarity);
         MXC_GPIO_EnableInt(pb_pin[pb].port, pb_pin[pb].mask);
         NVIC_EnableIRQ((IRQn_Type)MXC_GPIO_GET_IRQ(MXC_GPIO_GET_IDX(pb_pin[pb].port)));
     } else {
@@ -113,7 +142,11 @@ void PB_IntClear(unsigned int pb)
 int PB_Get(unsigned int pb)
 {
     MXC_ASSERT(pb < num_pbs);
-    return !MXC_GPIO_InGet(pb_pin[pb].port, pb_pin[pb].mask);
+    uint32_t state = MXC_GPIO_InGet(pb_pin[pb].port, pb_pin[pb].mask);
+    if (g_pb_polarity[pb] == PB_POLARITY_LOW) {
+        state = !state;
+    }
+    return state;
 }
 
 //******************************************************************************

Libraries/MiscDrivers/PushButton/pb.h

@@ -40,6 +40,11 @@ extern "C" {
 extern const mxc_gpio_cfg_t pb_pin[];
 extern const unsigned int num_pbs;
 
+typedef enum pb_polarity {
+    PB_POLARITY_LOW, ///< Pushing the button sends the signal LOW.  When the button is open, the signal is HIGH
+    PB_POLARITY_HIGH ///< Pushing the button sends the signal HIGH.  When the button is open, the signal is LOW.
+} pb_polarity_t;
+
 /* **** Function Prototypes **** */
 
 /**
@@ -50,6 +55,13 @@ extern const unsigned int num_pbs;
  */
 int PB_Init(void);
 
+/**
+ * @brief           Set the voltage polarity of the pushbutton.
+ * @param pb        Pushbutton to configure
+ * @param polarity  Desired polarity of the push-button (i.e. what voltage level the signal goes to when the button is pushed).
+ */
+int PB_Set_Polarity(unsigned int pb, pb_polarity_t polarity);
+
 /**
  * Type alias @c pb_callback for the push button callback.
  * @details The function is of type: