Merge remote-tracking branch 'origin/master' into misoc

arch/arm/src/calypso/calypso_keypad.c

@@ -36,6 +36,7 @@
 #include <nuttx/config.h>
 
 #include <nuttx/arch.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/irq.h>
 #include <nuttx/fs/fs.h>
 
@@ -360,9 +361,13 @@ int calypso_kbd_irq(int irq, uint32_t * regs)
 
 void up_keypad(void)
 {
-  /* Semaphore; helps leaving IRQ ctx as soon as possible */
+  /* kbssem semaphore helps leaving IRQ ctx as soon as possible.  This
+   * semaphore is used for signaling and, hence, should not have priority
+   * inheritance enabled.
+   */
 
   sem_init(&kbdsem, 0, 0);
+  sem_setprotocol(&kbdsem, SEM_PRIO_NONE);
 
   /* Drive cols low in idle state such that all buttons cause events */
 

arch/arm/src/efm32/efm32_i2c.c

@@ -71,8 +71,9 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/irq.h>
-#include <nuttx/i2c/i2c_master.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
+#include <nuttx/i2c/i2c_master.h>
 
 #include <arch/board/board.h>
 
@@ -681,8 +682,14 @@ static inline void efm32_i2c_sem_post(FAR struct efm32_i2c_priv_s *priv)
 static inline void efm32_i2c_sem_init(FAR struct efm32_i2c_priv_s *priv)
 {
   sem_init(&priv->sem_excl, 0, 1);
+
 #ifndef CONFIG_I2C_POLLED
+  /* This semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&priv->sem_isr, 0, 0);
+  sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
 

arch/arm/src/efm32/efm32_spi.c

@@ -53,6 +53,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/spi/spi.h>
 
 #include <arch/board/board.h>
@@ -1640,6 +1641,13 @@ static int spi_portinitialize(struct efm32_spidev_s *priv)
 
   (void)sem_init(&priv->rxdmasem, 0, 0);
   (void)sem_init(&priv->txdmasem, 0, 0);
+
+  /* These semaphores are used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+   sem_setprotocol(&priv->rxdmasem, SEM_PRIO_NONE);
+   sem_setprotocol(&priv->txdmasem, SEM_PRIO_NONE);
 #endif
 
   /* Enable SPI */

arch/arm/src/efm32/efm32_usbhost.c

@@ -52,6 +52,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/usbhost.h>
 #include <nuttx/usb/usbhost_devaddr.h>
@@ -5157,6 +5158,12 @@ static inline void efm32_sw_initialize(FAR struct efm32_usbhost_s *priv)
   sem_init(&priv->pscsem,  0, 0);
   sem_init(&priv->exclsem, 0, 1);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->pscsem, SEM_PRIO_NONE);
+
   /* Initialize the driver state data */
 
   priv->smstate   = SMSTATE_DETACHED;
@@ -5172,8 +5179,15 @@ static inline void efm32_sw_initialize(FAR struct efm32_usbhost_s *priv)
   for (i = 0; i < EFM32_MAX_TX_FIFOS; i++)
     {
       FAR struct efm32_chan_s *chan = &priv->chan[i];
+
       chan->chidx = i;
+
+      /* The waitsem semaphore is used for signaling and, hence, should not
+       * have priority inheritance enabled.
+       */
+
       sem_init(&chan->waitsem,  0, 0);
+      sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
 

arch/arm/src/imx1/imx_spi.c

@@ -50,6 +50,7 @@
 #include <nuttx/spi/spi.h>
 
 #include <nuttx/irq.h>
+#include <nuttx/semaphore.h>
 #include <arch/board/board.h>
 
 #include "up_internal.h"
@@ -1116,7 +1117,13 @@ FAR struct spi_dev_s *imx_spibus_initialize(int port)
   /* Initialize the state structure */
 
 #ifndef CONFIG_SPI_POLLWAIT
+  /* Initialize the semaphore that is used to wake up the waiting
+   * thread when the DMA transfer completes.  This semaphore is used for
+   * signaling and, hence, should not have priority inheritance enabled.
+   */
+
    sem_init(&priv->waitsem, 0, 0);
+   sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 #endif
    sem_init(&priv->exclsem, 0, 1);
 

arch/arm/src/kinetis/kinetis_i2c.c

@@ -49,6 +49,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/i2c/i2c_master.h>
 
 #include <nuttx/irq.h>
@@ -1105,9 +1106,17 @@ struct i2c_master_s *kinetis_i2cbus_initialize(int port)
 
   leave_critical_section(flags);
 
+  /* Initialize semaphores */
+
   sem_init(&priv->mutex, 0, 1);
   sem_init(&priv->wait, 0, 0);
 
+  /* The wait semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->wait, SEM_PRIO_NONE);
+
   /* Allocate a watchdog timer */
 
   priv->timeout = wd_create();

arch/arm/src/kinetis/kinetis_sdhc.c

@@ -52,6 +52,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/sdio.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/mmcsd.h>
 
 #include <nuttx/irq.h>
@@ -2774,8 +2775,18 @@ FAR struct sdio_dev_s *sdhc_initialize(int slotno)
   DEBUGASSERT(slotno == 0);
 
   /* Initialize the SDHC slot structure data structure */
+  /* Initialize semaphores */
 
   sem_init(&priv->waitsem, 0, 0);
+
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
+  /* Create a watchdog timer */
+
   priv->waitwdog = wd_create();
   DEBUGASSERT(priv->waitwdog);
 

arch/arm/src/lpc11xx/lpc11_i2c.c

@@ -59,6 +59,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/i2c/i2c_master.h>
 
 #include <nuttx/irq.h>
@@ -584,9 +585,17 @@ struct i2c_master_s *lpc11_i2cbus_initialize(int port)
 
   putreg32(I2C_CONSET_I2EN, priv->base + LPC11_I2C_CONSET_OFFSET);
 
+  /* Initialize semaphores */
+
   sem_init(&priv->mutex, 0, 1);
   sem_init(&priv->wait, 0, 0);
 
+  /* The wait semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->wait, SEM_PRIO_NONE);
+
   /* Allocate a watchdog timer */
 
   priv->timeout = wd_create();

arch/arm/src/lpc17xx/lpc17_i2c.c

@@ -59,6 +59,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/i2c/i2c_master.h>
 
 #include <nuttx/irq.h>
@@ -589,9 +590,17 @@ struct i2c_master_s *lpc17_i2cbus_initialize(int port)
 
   putreg32(I2C_CONSET_I2EN, priv->base + LPC17_I2C_CONSET_OFFSET);
 
+  /* Initialize semaphores */
+
   sem_init(&priv->mutex, 0, 1);
   sem_init(&priv->wait, 0, 0);
 
+  /* The wait semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->wait, SEM_PRIO_NONE);
+
   /* Allocate a watchdog timer */
 
   priv->timeout = wd_create();

arch/arm/src/lpc17xx/lpc17_sdcard.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/lpc17xx/lpc17_sdcard.c
  *
- *   Copyright (C) 2013-2014 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013-2014, 2016 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -52,6 +52,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/sdio.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/mmcsd.h>
 
 #include <nuttx/irq.h>
@@ -2699,8 +2700,18 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   putreg32(regval, LPC17_SYSCON_PCONP);
 
   /* Initialize the SD card slot structure */
+  /* Initialize semaphores */
 
   sem_init(&priv->waitsem, 0, 0);
+
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
+  /* Create a watchdog timer */
+
   priv->waitwdog = wd_create();
   DEBUGASSERT(priv->waitwdog);
 

arch/arm/src/lpc17xx/lpc17_usbhost.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/lpc17xx/lpc17_usbhost.c
  *
- *   Copyright (C) 2010-2012, 2014-2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2010-2012, 2014-2016 Gregory Nutt. All rights reserved.
  *   Authors: Rafael Noronha <rafael@pdsolucoes.com.br>
  *            Gregory Nutt <gnutt@nuttx.org>
  *
@@ -51,6 +51,7 @@
 #include <debug.h>
 
 #include <nuttx/arch.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/ohci.h>
 #include <nuttx/usb/usbhost.h>
@@ -2262,10 +2263,12 @@ static int lpc17_epalloc(struct usbhost_driver_s *drvr,
       uinfo("EP%d CTRL:%08x\n", epdesc->addr, ed->hw.ctrl);
 
       /* Initialize the semaphore that is used to wait for the endpoint
-       * WDH event.
+       * WDH event. The wdhsem semaphore is used for signaling and, hence,
+       * should not have priority inheritance enabled.
        */
 
       sem_init(&ed->wdhsem, 0, 0);
+      sem_setprotocol(&priv->wdhsem, SEM_PRIO_NONE);
 
       /* Link the common tail TD to the ED's TD list */
 
@@ -3639,6 +3642,12 @@ struct usbhost_connection_s *lpc17_usbhost_initialize(int controller)
   sem_init(&priv->pscsem,  0, 0);
   sem_init(&priv->exclsem, 0, 1);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->pscsem, SEM_PRIO_NONE);
+
 #ifndef CONFIG_USBHOST_INT_DISABLE
   priv->ininterval  = MAX_PERINTERVAL;
   priv->outinterval = MAX_PERINTERVAL;
@@ -3719,7 +3728,13 @@ struct usbhost_connection_s *lpc17_usbhost_initialize(int controller)
   memset((void *)HCCA,   0, sizeof(struct ohci_hcca_s));
   memset((void *)TDTAIL, 0, sizeof(struct ohci_gtd_s));
   memset((void *)EDCTRL, 0, sizeof(struct lpc17_ed_s));
+
+  /* The EDCTRL wdhsem semaphore is used for signaling and, hence, should
+   * not have priority inheritance enabled.
+   */
+
   sem_init(&EDCTRL->wdhsem, 0, 0);
+  sem_setprotocol(&EDCTRL->wdhsem, SEM_PRIO_NONE);
 
   /* Initialize user-configurable EDs */
 

arch/arm/src/lpc2378/lpc23xx_i2c.c

@@ -64,6 +64,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/i2c/i2c_master.h>
 
 #include <nuttx/irq.h>
@@ -600,9 +601,17 @@ struct i2c_master_s *lpc2378_i2cbus_initialize(int port)
 
   putreg32(I2C_CONSET_I2EN, priv->base + I2C_CONSET_OFFSET);
 
+  /* Initialize semaphores */
+
   sem_init(&priv->mutex, 0, 1);
   sem_init(&priv->wait, 0, 0);
 
+  /* The wait semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->wait, SEM_PRIO_NONE);
+
   /* Allocate a watchdog timer */
 
   priv->timeout = wd_create();

arch/arm/src/lpc31xx/lpc31_ehci.c

@@ -52,6 +52,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/usbhost.h>
 #include <nuttx/usb/ehci.h>
@@ -3931,7 +3932,13 @@ static int lpc31_epalloc(FAR struct usbhost_driver_s *drvr,
   epinfo->maxpacket = epdesc->mxpacketsize;
   epinfo->xfrtype   = epdesc->xfrtype;
   epinfo->speed     = hport->speed;
+
+  /* The iocsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&epinfo->iocsem, 0, 0);
+  sem_setprotocol(&epinfo->iocsem, SEM_PRIO_NONE);
 
   /* Success.. return an opaque reference to the endpoint information structure
    * instance
@@ -4916,6 +4923,12 @@ FAR struct usbhost_connection_s *lpc31_ehci_initialize(int controller)
   sem_init(&g_ehci.exclsem, 0, 1);
   sem_init(&g_ehci.pscsem,  0, 0);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&g_ehci.pscsem, SEM_PRIO_NONE);
+
   /* Initialize EP0 */
 
   sem_init(&g_ehci.ep0.iocsem, 0, 1);
@@ -4952,7 +4965,13 @@ FAR struct usbhost_connection_s *lpc31_ehci_initialize(int controller)
       rhport->ep0.xfrtype         = USB_EP_ATTR_XFER_CONTROL;
       rhport->ep0.speed           = USB_SPEED_FULL;
       rhport->ep0.maxpacket       = 8;
+
+      /* The port iocsem semaphore is used for signaling and, hence,
+       * should not have priority inheritance enabled.
+       */
+
       sem_init(&rhport->ep0.iocsem, 0, 0);
+      sem_setprotocol(&rhport->iocsem, SEM_PRIO_NONE);
 
       /* Initialize the public port representation */
 

arch/arm/src/lpc31xx/lpc31_i2c.c

@@ -51,6 +51,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/i2c/i2c_master.h>
 
 #include <nuttx/irq.h>
@@ -554,9 +555,17 @@ struct i2c_master_s *lpc31_i2cbus_initialize(int port)
   priv->rstid = (port == 0) ? RESETID_I2C0RST  : RESETID_I2C1RST;
   priv->irqid = (port == 0) ? LPC31_IRQ_I2C0   : LPC31_IRQ_I2C1;
 
+  /* Initialize semaphores */
+
   sem_init(&priv->mutex, 0, 1);
   sem_init(&priv->wait, 0, 0);
 
+  /* The wait semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->wait, SEM_PRIO_NONE);
+
   /* Enable I2C system clocks */
 
   lpc31_enableclock(priv->clkid);

arch/arm/src/lpc43xx/lpc43_ehci.c

@@ -51,6 +51,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/usbhost.h>
 #include <nuttx/usb/ehci.h>
@@ -3768,7 +3769,13 @@ static int lpc43_epalloc(FAR struct usbhost_driver_s *drvr,
   epinfo->maxpacket = epdesc->mxpacketsize;
   epinfo->xfrtype   = epdesc->xfrtype;
   epinfo->speed     = hport->speed;
+
+  /* The endpoint iocsem semaphore is used for signaling and, hence,
+   * should not have priority inheritance enabled.
+   */
+
   sem_init(&epinfo->iocsem, 0, 0);
+  sem_setprotocol(&epinfo->iocsem, SEM_PRIO_NONE);
 
   /* Success.. return an opaque reference to the endpoint information structure
    * instance
@@ -4747,6 +4754,12 @@ FAR struct usbhost_connection_s *lpc43_ehci_initialize(int controller)
   sem_init(&g_ehci.exclsem, 0, 1);
   sem_init(&g_ehci.pscsem,  0, 0);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&g_ehci.pscsem, SEM_PRIO_NONE);
+
   /* Initialize EP0 */
 
   sem_init(&g_ehci.ep0.iocsem, 0, 1);
@@ -4783,7 +4796,13 @@ FAR struct usbhost_connection_s *lpc43_ehci_initialize(int controller)
       rhport->ep0.xfrtype         = USB_EP_ATTR_XFER_CONTROL;
       rhport->ep0.speed           = USB_SPEED_FULL;
       rhport->ep0.maxpacket       = 8;
+
+      /* The EP0 iocsem semaphore is used for signaling and, hence, should
+       * not have priority inheritance enabled.
+       */
+
       sem_init(&rhport->ep0.iocsem, 0, 0);
+      sem_setprotocol(&rhport->ep0.iocsem, SEM_PRIO_NONE);
 
       /* Initialize the public port representation */
 

arch/arm/src/lpc43xx/lpc43_i2c.c

@@ -62,6 +62,7 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/i2c/i2c_master.h>
 
 #include <nuttx/irq.h>
@@ -539,9 +540,17 @@ struct i2c_master_s *lpc43_i2cbus_initialize(int port)
 
   putreg32(I2C_CONSET_I2EN, priv->base + LPC43_I2C_CONSET_OFFSET);
 
+  /* Initialize semaphores */
+
   sem_init(&priv->mutex, 0, 1);
   sem_init(&priv->wait, 0, 0);
 
+  /* The wait semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->wait, SEM_PRIO_NONE);
+
   /* Allocate a watchdog timer */
 
   priv->timeout = wd_create();

arch/arm/src/sam34/sam_hsmci.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/sam34/sam_hsmci.c
  *
- *   Copyright (C) 2010, 2012-2014 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2010, 2012-2014, 2016 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -52,6 +52,7 @@
 #include <nuttx/clock.h>
 #include <nuttx/sdio.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/mmcsd.h>
 
 #include <nuttx/irq.h>
@@ -2668,8 +2669,18 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   mcinfo("slotno: %d\n", slotno);
 
   /* Initialize the HSMCI slot structure */
+  /* Initialize semaphores */
 
   sem_init(&priv->waitsem, 0, 0);
+
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
+  /* Create a watchdog timer */
+
   priv->waitwdog = wd_create();
   DEBUGASSERT(priv->waitwdog);
 

arch/arm/src/sam34/sam_spi.c

@@ -56,6 +56,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/spi/spi.h>
 
 #include "up_internal.h"
@@ -1882,10 +1883,12 @@ struct spi_dev_s *sam_spibus_initialize(int port)
 
 #ifdef CONFIG_SAM34_SPI_DMA
       /* Initialize the SPI semaphore that is used to wake up the waiting
-       * thread when the DMA transfer completes.
+       * thread when the DMA transfer completes.  This semaphore is used for
+       * signaling and, hence, should not have priority inheritance enabled.
        */
 
       sem_init(&spics->dmawait, 0, 0);
+      sem_setprotocol(&spics->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
 

arch/arm/src/sam34/sam_twi.c

@@ -56,6 +56,7 @@
 
 #include <nuttx/wdog.h>
 #include <nuttx/arch.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/i2c/i2c_master.h>
 
 #include <nuttx/irq.h>
@@ -982,9 +983,17 @@ struct i2c_master_s *sam_i2cbus_initialize(int bus)
 
   priv->dev.ops = &g_twiops;
 
+  /* Initialize semaphores */
+
   sem_init(&priv->exclsem, 0, 1);
   sem_init(&priv->waitsem, 0, 0);
 
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
   /* Allocate a watchdog timer */
 
   priv->timeout = wd_create();

arch/arm/src/sama5/sam_ehci.c

@@ -51,6 +51,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/usbhost.h>
 #include <nuttx/usb/ehci.h>
@@ -3752,7 +3753,13 @@ static int sam_epalloc(FAR struct usbhost_driver_s *drvr,
   epinfo->maxpacket = epdesc->mxpacketsize;
   epinfo->xfrtype   = epdesc->xfrtype;
   epinfo->speed     = hport->speed;
+
+  /* The endpoint iocsem semaphore is used for signaling and, hence,
+   * should not have priority inheritance enabled.
+   */
+
   sem_init(&epinfo->iocsem, 0, 0);
+  sem_setprotocol(&epinfo->iocsem, SEM_PRIO_NONE);
 
   /* Success.. return an opaque reference to the endpoint information structure
    * instance
@@ -4787,6 +4794,12 @@ FAR struct usbhost_connection_s *sam_ehci_initialize(int controller)
   sem_init(&g_ehci.exclsem, 0, 1);
   sem_init(&g_ehci.pscsem,  0, 0);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&g_ehci.pscsem, SEM_PRIO_NONE);
+
   /* Initialize EP0 */
 
   sem_init(&g_ehci.ep0.iocsem, 0, 1);
@@ -4823,7 +4836,13 @@ FAR struct usbhost_connection_s *sam_ehci_initialize(int controller)
       rhport->ep0.xfrtype         = USB_EP_ATTR_XFER_CONTROL;
       rhport->ep0.speed           = USB_SPEED_FULL;
       rhport->ep0.maxpacket       = 8;
+
+      /* The endpoint 0 iocsem semaphore is used for signaling and, hence,
+       * should not have priority inheritance enabled.
+       */
+
       sem_init(&rhport->ep0.iocsem, 0, 0);
+      sem_setprotocol(&rhport->ep0.iocsem, SEM_PRIO_NONE);
 
       /* Initialize the public port representation */
 

arch/arm/src/sama5/sam_hsmci.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/sama5/sam_hsmci.c
  *
- *   Copyright (C) 2013-2014 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013-2014, 2016 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -52,6 +52,7 @@
 #include <nuttx/wdog.h>
 #include <nuttx/sdio.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/mmcsd.h>
 
 #include <nuttx/irq.h>
@@ -3331,8 +3332,18 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
          priv, priv->base, priv->hsmci, dmac, pid);
 
   /* Initialize the HSMCI slot structure */
+  /* Initialize semaphores */
 
   sem_init(&priv->waitsem, 0, 0);
+
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
+  /* Create a watchdog timer */
+
   priv->waitwdog = wd_create();
   DEBUGASSERT(priv->waitwdog);
 

arch/arm/src/sama5/sam_nand.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/sama5/sam_nand.c
  *
- *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013, 2016 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * References:
@@ -58,6 +58,7 @@
 #include <debug.h>
 
 #include <nuttx/arch.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/fs/ioctl.h>
 #include <nuttx/mtd/mtd.h>
 #include <nuttx/mtd/nand.h>
@@ -2944,7 +2945,12 @@ struct mtd_dev_s *sam_nand_initialize(int cs)
   priv->cs             = cs;
 
 #ifdef CONFIG_SAMA5_NAND_DMA
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&priv->waitsem, 0, 0);
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 #endif
 
   /* Perform one-time, global NFC/PMECC initialization */
@@ -2956,8 +2962,14 @@ struct mtd_dev_s *sam_nand_initialize(int cs)
 #if NAND_NBANKS > 1
       sem_init(&g_nand.exclsem, 0, 1);
 #endif
+
 #ifdef CONFIG_SAMA5_NAND_HSMCINTERRUPTS
+      /* The waitsem semaphore is used for signaling and, hence, should not
+       * have priority inheritance enabled.
+       */
+
       sem_init(&g_nand.waitsem, 0, 0);
+      sem_setprotocol(&g_nand.waitsem, SEM_PRIO_NONE);
 #endif
 
       /* Enable the NAND FLASH Controller (The NFC is always used) */

arch/arm/src/sama5/sam_ohci.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/sama5/sam_ohci.c
  *
- *   Copyright (C) 2013, 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2013, 2015-2016 Gregory Nutt. All rights reserved.
  *   Authors: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -51,6 +51,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/ohci.h>
 #include <nuttx/usb/usbhost.h>
@@ -2664,6 +2665,12 @@ static int sam_epalloc(struct usbhost_driver_s *drvr,
 
   sem_init(&eplist->wdhsem, 0, 0);
 
+  /* The wdhsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&eplist->wdhsem, SEM_PRIO_NONE);
+
   /* We must have exclusive access to the ED pool, the bulk list, the periodic list
    * and the interrupt table.
    */
@@ -3903,6 +3910,12 @@ struct usbhost_connection_s *sam_ohci_initialize(int controller)
   sem_init(&g_ohci.pscsem,  0, 0);
   sem_init(&g_ohci.exclsem, 0, 1);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&g_ohci.pscsem, SEM_PRIO_NONE);
+
 #ifndef CONFIG_USBHOST_INT_DISABLE
   g_ohci.ininterval  = MAX_PERINTERVAL;
   g_ohci.outinterval = MAX_PERINTERVAL;

arch/arm/src/sama5/sam_spi.c

@@ -60,6 +60,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/spi/spi.h>
 
 #include "up_internal.h"
@@ -1810,10 +1811,12 @@ struct spi_dev_s *sam_spibus_initialize(int port)
 
 #ifdef CONFIG_SAMA5_SPI_DMA
       /* Initialize the SPI semaphore that is used to wake up the waiting
-       * thread when the DMA transfer completes.
+       * thread when the DMA transfer completes.  This semaphore is used for
+       * signaling and, hence, should not have priority inheritance enabled.
        */
 
       sem_init(&spics->dmawait, 0, 0);
+      sem_setprotocol(&spics->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
 

arch/arm/src/sama5/sam_trng.c

@@ -52,6 +52,7 @@
 
 #include <nuttx/irq.h>
 #include <nuttx/arch.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/fs/fs.h>
 #include <nuttx/drivers/drivers.h>
 
@@ -352,9 +353,18 @@ static int sam_rng_initialize(void)
   /* Initialize the device structure */
 
   memset(&g_trngdev, 0, sizeof(struct trng_dev_s));
+
+  /* Initialize semphores */
+
   sem_init(&g_trngdev.exclsem, 0, 1);
   sem_init(&g_trngdev.waitsem, 0, 0);
 
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&g_trngdev.waitsem, SEM_PRIO_NONE);
+
   /* Enable clocking to the TRNG */
 
   sam_trng_enableclk();

arch/arm/src/sama5/sam_tsd.c

@@ -66,6 +66,7 @@
 #include <nuttx/wdog.h>
 #include <nuttx/wqueue.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/input/touchscreen.h>
 
 #include <arch/board/board.h>
@@ -1669,7 +1670,12 @@ int sam_tsd_register(struct sam_adc_s *adc, int minor)
   priv->threshx = INVALID_THRESHOLD; /* Initialize thresholding logic */
   priv->threshy = INVALID_THRESHOLD; /* Initialize thresholding logic */
 
-  sem_init(&priv->waitsem, 0, 0);    /* Initialize pen event wait semaphore */
+  /* Initialize pen event wait semaphore.  This semaphore is used for
+   * signaling and, hence, should not have priority inheritance enabled.
+   */
+
+  sem_init(&priv->waitsem, 0, 0);
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
 
   /* Register the device as an input device */
 

arch/arm/src/sama5/sam_twi.c

@@ -57,6 +57,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/i2c/i2c_master.h>
 
 #include <nuttx/irq.h>
@@ -1306,9 +1307,17 @@ struct i2c_master_s *sam_i2cbus_initialize(int bus)
 
   priv->dev.ops = &g_twiops;
 
+  /* Initialize semaphores */
+
   (void)sem_init(&priv->exclsem, 0, 1);
   (void)sem_init(&priv->waitsem, 0, 0);
 
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
   /* Perform repeatable TWI hardware initialization */
 
   twi_hw_initialize(priv, frequency);

arch/arm/src/samv7/sam_hsmci.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/samv7/sam_hsmci.c
  *
- *   Copyright (C) 2015 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2015-2016 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -52,6 +52,7 @@
 #include <nuttx/wdog.h>
 #include <nuttx/sdio.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/mmcsd.h>
 
 #include <nuttx/irq.h>
@@ -3352,8 +3353,18 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
         priv, priv->base, priv->hsmci, pid);
 
   /* Initialize the HSMCI slot structure */
+  /* Initialize semaphores */
 
   sem_init(&priv->waitsem, 0, 0);
+
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
+  /* Create a watchdog timer */
+
   priv->waitwdog = wd_create();
   DEBUGASSERT(priv->waitwdog);
 

arch/arm/src/samv7/sam_qspi.c

@@ -55,6 +55,7 @@
 #include <nuttx/wdog.h>
 #include <nuttx/clock.h>
 #include <nuttx/kmalloc.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/spi/qspi.h>
 
 #include "up_internal.h"
@@ -1790,10 +1791,12 @@ struct qspi_dev_s *sam_qspi_initialize(int intf)
         }
 
       /* Initialize the QSPI semaphore that is used to wake up the waiting
-       * thread when the DMA transfer completes.
+       * thread when the DMA transfer completes.  This semaphore is used for
+       * signaling and, hence, should not have priority inheritance enabled.
        */
 
       sem_init(&priv->dmawait, 0, 0);
+      sem_setprotocol(&priv->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
 

arch/arm/src/samv7/sam_spi.c

@@ -56,6 +56,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/spi/spi.h>
 
 #include "up_internal.h"
@@ -626,7 +627,7 @@ static inline uint32_t spi_cs2pcs(struct sam_spics_s *spics)
 #ifndef CONFIG_SAMV7_SPI_CS_DECODING
   return ((uint32_t)1 << (spics->cs)) - 1;
 #else
-  return spics->cs;
+  return spics->cs - 1;
 #endif
 }
 
@@ -2164,10 +2165,12 @@ FAR struct spi_dev_s *sam_spibus_initialize(int port)
 
 #ifdef CONFIG_SAMV7_SPI_DMA
       /* Initialize the SPI semaphore that is used to wake up the waiting
-       * thread when the DMA transfer completes.
+       * thread when the DMA transfer completes.  This semaphore is used for
+       * signaling and, hence, should not have priority inheritance enabled.
        */
 
       sem_init(&spics->dmawait, 0, 0);
+      sem_setprotocol(&spics->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
 

arch/arm/src/samv7/sam_trng.c

@@ -53,6 +53,7 @@
 
 #include <nuttx/irq.h>
 #include <nuttx/arch.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/fs/fs.h>
 #include <nuttx/drivers/drivers.h>
 
@@ -353,9 +354,18 @@ static int sam_rng_initialize(void)
   /* Initialize the device structure */
 
   memset(&g_trngdev, 0, sizeof(struct trng_dev_s));
+
+  /* Initialize semaphores */
+
   sem_init(&g_trngdev.exclsem, 0, 1);
   sem_init(&g_trngdev.waitsem, 0, 0);
 
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&g_trngdev.waitsem, SEM_PRIO_NONE);
+
   /* Enable clocking to the TRNG */
 
   sam_trng_enableclk();

arch/arm/src/samv7/sam_twihs.c

@@ -57,6 +57,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/wdog.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/i2c/i2c_master.h>
 
 #include <nuttx/irq.h>
@@ -1454,9 +1455,17 @@ struct i2c_master_s *sam_i2cbus_initialize(int bus)
 
       priv->dev.ops = &g_twiops;
 
+      /* Initialize semaphores */
+
       (void)sem_init(&priv->exclsem, 0, 1);
       (void)sem_init(&priv->waitsem, 0, 0);
 
+      /* The waitsem semaphore is used for signaling and, hence, should not
+       * have priority inheritance enabled.
+       */
+
+      sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
       /* Perform repeatable TWIHS hardware initialization */
 
       twi_hw_initialize(priv, frequency);

arch/arm/src/stm32/stm32_1wire.c

@@ -56,6 +56,7 @@
 #include <nuttx/irq.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/drivers/1wire.h>
 
 #include <arch/board/board.h>
@@ -744,6 +745,12 @@ static inline void stm32_1wire_sem_init(FAR struct stm32_1wire_priv_s *priv)
 {
   sem_init(&priv->sem_excl, 0, 1);
   sem_init(&priv->sem_isr, 0, 0);
+
+  /* The sem_isr semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 }
 
 /****************************************************************************

arch/arm/src/stm32/stm32_dma2d.c

@@ -49,8 +49,9 @@
 #include <semaphore.h>
 
 #include <nuttx/irq.h>
-#include <nuttx/video/fb.h>
 #include <nuttx/kmalloc.h>
+#include <nuttx/semaphore.h>
+#include <nuttx/video/fb.h>
 
 #include <arch/chip/dma2d.h>
 #include <arch/board/board.h>
@@ -2167,9 +2168,13 @@ int up_dma2dinitialize(void)
 
       sem_init(&g_lock, 0, 1);
 
-      /* Initialize the semaphore for interrupt handling */
+      /* Initialize the semaphore for interrupt handling.  This waitsem
+       * semaphore is used for signaling and, hence, should not have
+       * priority inheritance enabled.
+       */
 
       sem_init(g_interrupt.sem, 0, 0);
+      sem_setprotocol(g_interrupt.sem, SEM_PRIO_NONE);
 
 #ifdef CONFIG_STM32_DMA2D_L8
       /* Enable dma2d transfer and clut loading interrupts only */

arch/arm/src/stm32/stm32_i2c.c

@@ -84,8 +84,9 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/irq.h>
-#include <nuttx/i2c/i2c_master.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
+#include <nuttx/i2c/i2c_master.h>
 
 #include <arch/board/board.h>
 
@@ -784,8 +785,14 @@ static inline void stm32_i2c_sem_post(struct stm32_i2c_priv_s *priv)
 static inline void stm32_i2c_sem_init(FAR struct stm32_i2c_priv_s *priv)
 {
   sem_init(&priv->sem_excl, 0, 1);
+
 #ifndef CONFIG_I2C_POLLED
+  /* This semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&priv->sem_isr, 0, 0);
+  sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
 

arch/arm/src/stm32/stm32_i2c_alt.c

@@ -91,8 +91,9 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/irq.h>
-#include <nuttx/i2c/i2c_master.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
+#include <nuttx/i2c/i2c_master.h>
 
 #include <arch/board/board.h>
 
@@ -792,8 +793,14 @@ static inline void stm32_i2c_sem_post(FAR struct stm32_i2c_priv_s *priv)
 static inline void stm32_i2c_sem_init(FAR struct stm32_i2c_priv_s *priv)
 {
   sem_init(&priv->sem_excl, 0, 1);
+
 #ifndef CONFIG_I2C_POLLED
+  /* This semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&priv->sem_isr, 0, 0);
+  sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
 

arch/arm/src/stm32/stm32_ltdc.c

@@ -49,8 +49,9 @@
 #include <debug.h>
 
 #include <nuttx/irq.h>
-#include <nuttx/video/fb.h>
 #include <nuttx/kmalloc.h>
+#include <nuttx/semaphore.h>
+#include <nuttx/video/fb.h>
 
 #include <arch/chip/ltdc.h>
 #include <arch/chip/dma2d.h>
@@ -1287,9 +1288,13 @@ static void stm32_global_configure(void)
 
   sem_init(&g_lock, 0, 1);
 
-  /* Initialize the semaphore for interrupt handling */
+  /* Initialize the semaphore for interrupt handling.  This waitsem
+   * semaphore is used for signaling and, hence, should not have priority
+   * inheritance enabled.
+   */
 
   sem_init(g_interrupt.sem, 0, 0);
+  sem_setprotocol(g_interrupt.sem, SEM_PRIO_NONE);
 
   /* Attach LTDC interrupt vector */
 

arch/arm/src/stm32/stm32_otgfshost.c

@@ -52,6 +52,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/usbhost.h>
 #include <nuttx/usb/usbhost_devaddr.h>
@@ -5091,6 +5092,12 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
   sem_init(&priv->pscsem,  0, 0);
   sem_init(&priv->exclsem, 0, 1);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->pscsem, SEM_PRIO_NONE);
+
   /* Initialize the driver state data */
 
   priv->smstate   = SMSTATE_DETACHED;
@@ -5106,8 +5113,15 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
   for (i = 0; i < STM32_MAX_TX_FIFOS; i++)
     {
       FAR struct stm32_chan_s *chan = &priv->chan[i];
+
       chan->chidx = i;
+
+      /* The waitsem semaphore is used for signaling and, hence, should not
+       * have priority inheritance enabled.
+       */
+
       sem_init(&chan->waitsem,  0, 0);
+      sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
 

arch/arm/src/stm32/stm32_otghshost.c

@@ -52,6 +52,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/usbhost.h>
 #include <nuttx/usb/usbhost_devaddr.h>
@@ -5091,6 +5092,12 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
   sem_init(&priv->pscsem,  0, 0);
   sem_init(&priv->exclsem, 0, 1);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+ sem_setprotocol(&priv->pscsem, SEM_PRIO_NONE);
+
   /* Initialize the driver state data */
 
   priv->smstate   = SMSTATE_DETACHED;
@@ -5106,8 +5113,15 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
   for (i = 0; i < STM32_MAX_TX_FIFOS; i++)
     {
       FAR struct stm32_chan_s *chan = &priv->chan[i];
+
       chan->chidx = i;
+
+      /* The waitsem semaphore is used for signaling and, hence, should not
+       * have priority inheritance enabled.
+       */
+
       sem_init(&chan->waitsem,  0, 0);
+      sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
 

arch/arm/src/stm32/stm32_sdio.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * arch/arm/src/stm32/stm32_sdio.c
  *
- *   Copyright (C) 2009, 2011-2014 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2009, 2011-2014, 2016 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -52,6 +52,7 @@
 #include <nuttx/clock.h>
 #include <nuttx/sdio.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/mmcsd.h>
 
 #include <nuttx/irq.h>
@@ -2853,8 +2854,18 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
   struct stm32_dev_s *priv = &g_sdiodev;
 
   /* Initialize the SDIO slot structure */
+  /* Initialize semaphores */
 
   sem_init(&priv->waitsem, 0, 0);
+
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
+  /* Create a watchdog timer */
+
   priv->waitwdog = wd_create();
   DEBUGASSERT(priv->waitwdog);
 

arch/arm/src/stm32/stm32_spi.c

@@ -70,6 +70,7 @@
 
 #include <nuttx/irq.h>
 #include <nuttx/arch.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/spi/spi.h>
 
 #include <arch/board/board.h>
@@ -1719,12 +1720,18 @@ static void spi_bus_initialize(FAR struct stm32_spidev_s *priv)
 
   sem_init(&priv->exclsem, 0, 1);
 
-  /* Initialize the SPI semaphores that is used to wait for DMA completion */
-
 #ifdef CONFIG_STM32_SPI_DMA
+  /* Initialize the SPI semaphores that is used to wait for DMA completion.
+   * This semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&priv->rxsem, 0, 0);
   sem_init(&priv->txsem, 0, 0);
 
+  sem_setprotocol(&priv->rxsem, SEM_PRIO_NONE);
+  sem_setprotocol(&priv->txsem, SEM_PRIO_NONE);
+
   /* Get DMA channels.  NOTE: stm32_dmachannel() will always assign the DMA channel.
    * if the channel is not available, then stm32_dmachannel() will block and wait
    * until the channel becomes available.  WARNING: If you have another device sharing

arch/arm/src/stm32/stm32f30xxx_i2c.c

@@ -85,8 +85,9 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/irq.h>
-#include <nuttx/i2c/i2c_master.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
+#include <nuttx/i2c/i2c_master.h>
 
 #include <arch/board/board.h>
 
@@ -899,8 +900,14 @@ static inline void stm32_i2c_sem_post(FAR struct stm32_i2c_priv_s *priv)
 static inline void stm32_i2c_sem_init(FAR struct stm32_i2c_priv_s *priv)
 {
   sem_init(&priv->sem_excl, 0, 1);
+
 #ifndef CONFIG_I2C_POLLED
+  /* This semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&priv->sem_isr, 0, 0);
+  sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
 

arch/arm/src/stm32/stm32f40xxx_i2c.c

@@ -84,8 +84,9 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/irq.h>
-#include <nuttx/i2c/i2c_master.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
+#include <nuttx/i2c/i2c_master.h>
 
 #include <arch/board/board.h>
 
@@ -786,8 +787,14 @@ static inline void stm32_i2c_sem_post(struct stm32_i2c_priv_s *priv)
 static inline void stm32_i2c_sem_init(FAR struct stm32_i2c_priv_s *priv)
 {
   sem_init(&priv->sem_excl, 0, 1);
+
 #ifndef CONFIG_I2C_POLLED
+  /* This semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&priv->sem_isr, 0, 0);
+  sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
 

arch/arm/src/stm32f7/stm32_i2c.c

@@ -231,9 +231,10 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/irq.h>
-#include <nuttx/i2c/i2c_master.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/clock.h>
+#include <nuttx/i2c/i2c_master.h>
 
 #include <arch/board/board.h>
 
@@ -1089,8 +1090,14 @@ static inline void stm32_i2c_sem_post(FAR struct i2c_master_s *dev)
 static inline void stm32_i2c_sem_init(FAR struct i2c_master_s *dev)
 {
   sem_init(&((struct stm32_i2c_inst_s *)dev)->priv->sem_excl, 0, 1);
+
 #ifndef CONFIG_I2C_POLLED
+  /* This semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&((struct stm32_i2c_inst_s *)dev)->priv->sem_isr, 0, 0);
+  sem_setprotocol(&((struct stm32_i2c_inst_s *)dev)->priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
 

arch/arm/src/stm32f7/stm32_otghost.c

@@ -53,6 +53,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/usbhost.h>
 #include <nuttx/usb/usbhost_devaddr.h>
@@ -5089,6 +5090,12 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
   sem_init(&priv->pscsem,  0, 0);
   sem_init(&priv->exclsem, 0, 1);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+ sem_setprotocol(&priv->pscsem, SEM_PRIO_NONE);
+
   /* Initialize the driver state data */
 
   priv->smstate   = SMSTATE_DETACHED;
@@ -5104,8 +5111,15 @@ static inline void stm32_sw_initialize(FAR struct stm32_usbhost_s *priv)
   for (i = 0; i < STM32_MAX_TX_FIFOS; i++)
     {
       FAR struct stm32_chan_s *chan = &priv->chan[i];
+
       chan->chidx = i;
+
+      /* The waitsem semaphore is used for signaling and, hence, should not
+       * have priority inheritance enabled.
+       */
+
       sem_init(&chan->waitsem,  0, 0);
+      sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
 

arch/arm/src/stm32f7/stm32_sdmmc.c

@@ -53,6 +53,7 @@
 #include <nuttx/clock.h>
 #include <nuttx/sdio.h>
 #include <nuttx/wqueue.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/mmcsd.h>
 
 #include <nuttx/irq.h>
@@ -3214,8 +3215,18 @@ FAR struct sdio_dev_s *sdio_initialize(int slotno)
     }
 
   /* Initialize the SDIO slot structure */
+  /* Initialize semaphores */
 
   sem_init(&priv->waitsem, 0, 0);
+
+  /* The waitsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+  sem_setprotocol(&priv->waitsem, SEM_PRIO_NONE);
+
+  /* Create a watchdog timer */
+
   priv->waitwdog = wd_create();
   DEBUGASSERT(priv->waitwdog);
 

arch/arm/src/stm32f7/stm32_spi.c

@@ -72,6 +72,7 @@
 
 #include <nuttx/irq.h>
 #include <nuttx/arch.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/spi/spi.h>
 
 #include <arch/board/board.h>
@@ -1665,16 +1666,22 @@ static void spi_bus_initialize(FAR struct stm32_spidev_s *priv)
 
   spi_putreg(priv, STM32_SPI_CRCPR_OFFSET, 7);
 
-  /* Initialize the SPI semaphore that enforces mutually exclusive access */
+  /* Initialize the SPI semaphore that enforces mutually exclusive access. */
 
   sem_init(&priv->exclsem, 0, 1);
 
-  /* Initialize the SPI semaphores that is used to wait for DMA completion */
-
 #ifdef CONFIG_STM32F7_SPI_DMA
+  /* Initialize the SPI semaphores that is used to wait for DMA completion.
+   * This semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&priv->rxsem, 0, 0);
   sem_init(&priv->txsem, 0, 0);
 
+  sem_setprotocol(&priv->rxsem, SEM_PRIO_NONE);
+  sem_setprotocol(&priv->txsem, SEM_PRIO_NONE);
+
   /* Get DMA channels.  NOTE: stm32_dmachannel() will always assign the DMA channel.
    * if the channel is not available, then stm32_dmachannel() will block and wait
    * until the channel becomes available.  WARNING: If you have another device sharing

arch/arm/src/stm32l4/stm32l4_i2c.c

@@ -81,8 +81,9 @@
 
 #include <nuttx/arch.h>
 #include <nuttx/irq.h>
-#include <nuttx/i2c/i2c_master.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
+#include <nuttx/i2c/i2c_master.h>
 
 #include <arch/board/board.h>
 
@@ -843,8 +844,14 @@ static inline void stm32l4_i2c_sem_post(FAR struct stm32l4_i2c_priv_s *priv)
 static inline void stm32l4_i2c_sem_init(FAR struct stm32l4_i2c_priv_s *priv)
 {
   sem_init(&priv->sem_excl, 0, 1);
+
 #ifndef CONFIG_I2C_POLLED
+  /* This semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
   sem_init(&priv->sem_isr, 0, 0);
+  sem_setprotocol(&priv->sem_isr, SEM_PRIO_NONE);
 #endif
 }
 

arch/arm/src/stm32l4/stm32l4_otgfshost.c

@@ -53,6 +53,7 @@
 #include <nuttx/arch.h>
 #include <nuttx/kmalloc.h>
 #include <nuttx/clock.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/usb/usb.h>
 #include <nuttx/usb/usbhost.h>
 #include <nuttx/usb/usbhost_devaddr.h>
@@ -5096,6 +5097,12 @@ static inline void stm32l4_sw_initialize(FAR struct stm32l4_usbhost_s *priv)
   sem_init(&priv->pscsem,  0, 0);
   sem_init(&priv->exclsem, 0, 1);
 
+  /* The pscsem semaphore is used for signaling and, hence, should not have
+   * priority inheritance enabled.
+   */
+
+ sem_setprotocol(&priv->pscsem, SEM_PRIO_NONE);
+
   /* Initialize the driver state data */
 
   priv->smstate   = SMSTATE_DETACHED;
@@ -5111,8 +5118,15 @@ static inline void stm32l4_sw_initialize(FAR struct stm32l4_usbhost_s *priv)
   for (i = 0; i < STM32L4_MAX_TX_FIFOS; i++)
     {
       FAR struct stm32l4_chan_s *chan = &priv->chan[i];
+
       chan->chidx = i;
+
+      /* The waitsem semaphore is used for signaling and, hence, should not
+       * have priority inheritance enabled.
+       */
+
       sem_init(&chan->waitsem,  0, 0);
+      sem_setprotocol(&chan->waitsem, SEM_PRIO_NONE);
     }
 }
 

arch/arm/src/stm32l4/stm32l4_qspi.c

@@ -55,6 +55,7 @@
 #include <nuttx/wdog.h>
 #include <nuttx/clock.h>
 #include <nuttx/kmalloc.h>
+#include <nuttx/semaphore.h>
 #include <nuttx/spi/qspi.h>
 
 #include "up_internal.h"
@@ -2501,10 +2502,12 @@ struct qspi_dev_s *stm32l4_qspi_initialize(int intf)
         }
 
       /* Initialize the QSPI semaphore that is used to wake up the waiting
-       * thread when the DMA transfer completes.
+       * thread when the DMA transfer completes.  This semaphore is used for
+       * signaling and, hence, should not have priority inheritance enabled.
        */
 
       sem_init(&priv->dmawait, 0, 0);
+      sem_setprotocol(&priv->dmawait, SEM_PRIO_NONE);
 
       /* Create a watchdog time to catch DMA timeouts */
 
@@ -2526,10 +2529,13 @@ struct qspi_dev_s *stm32l4_qspi_initialize(int intf)
           goto errout_with_dmadog;
         }
 
-      /* Initialize the semaphore that blocks until the operation completes */
+      /* Initialize the semaphore that blocks until the operation completes.
+       * This semaphore is used for signaling and, hence, should not have
+       * priority inheritance enabled.
+       */
 
       sem_init(&priv->op_sem, 0, 0);
-
+      sem_setprotocol(&priv->op_sem, SEM_PRIO_NONE);
 #endif
 
       /* Perform hardware initialization.  Puts the QSPI into an active