Add eZ80 SPI driver

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@1668 42af7a65-404d-4744-a932-0658087f49c3

ChangeLog

@@ -682,3 +682,7 @@
 	network setup to perform that testing now (I'm in a hotel).
 
 0.4.5 2009-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr>
+
+	* Add an enumeration argument to the SPI chip select and status methods so
+	  that the interface can handle more than one device.
+	* eZ80Acclaim!: Add a generic SPI driver for all eZ80 boards.

Documentation/NuttX.html

@@ -1356,6 +1356,10 @@ buildroot-0.1.3 2009-02-28 <spudmonkey@racsa.co.cr>
 <pre><ul>
 nuttx-0.4.5 2009-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 
+	* Add an enumeration argument to the SPI chip select and status methods so
+	  that the interface can handle more than one device.
+	* eZ80Acclaim!: Add a generic SPI driver for all eZ80 boards.
+
 pascal-0.1.3 2009-xx-xx Gregory Nutt &lt;spudmonkey@racsa.co.cr&gt;
 
 buildroot-0.1.4 2009-xx-xx &lt;spudmonkey@racsa.co.cr&gt;

TODO

@@ -688,6 +688,12 @@ o z80/z8/ez80 (arch/z80)
   Status:      Open
   Priority:    High if you happen to be working with XTRS.
 
+  Description: A "generic" SPI driver has been coded for the eZ80Acclaim!
+               However, this remains untested since I have no SPI devices for
+               the board (yet).
+  Status:      Open
+  Priority:    Med
+
 o z16 (arch/z16)
 ^^^^^^^^^^^^^^^^
 

arch/z80/src/ez80/Make.defs

@@ -52,7 +52,7 @@ endif
 CHIP_SSRCS	= 
 CHIP_CSRCS	= ez80_clock.c ez80_initialstate.c ez80_irq.c ez80_copystate.c \
 		  ez80_schedulesigaction.c ez80_sigdeliver.c ez80_timerisr.c \
-		  ez80_lowuart.c ez80_serial.c ez80_registerdump.c
+		  ez80_lowuart.c ez80_serial.c ez80_spi.c ez80_registerdump.c
 ifeq ($(CONFIG_ARCH_CHIP_EZ80F91),y)
 ifeq ($(CONFIG_EZ80_EMAC),y)
 CHIP_CSRCS	+= ez80_emac.c

arch/z80/src/ez80/ez80_spi.c

@@ -0,0 +1,376 @@
+/****************************************************************************
+ * arch/z80/src/ez80/ez80_spi.c
+ *
+ *   Copyright (C) 2009 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/spi.h>
+
+#include <arch/board/board.h>
+#include <nuttx/arch.h>
+#include <nuttx/spi.h>
+#include <arch/io.h>
+
+#include "up_internal.h"
+#include "up_arch.h"
+
+#include "chip.h"
+#include "ez80f91_spi.h"
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+#ifdef CONFIG_ARCH_CHIP_EZ80F91
+# define GPIOB_SPI_PINSET  0x38  /* MISO+MSOI+SCK. Excludes SS */
+#else
+#  error "Check GPIO initialization for this chip"
+#endif
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static uint32 spi_setfrequency(FAR struct spi_dev_s *dev, uint32 frequency);
+static ubyte  spi_sndbyte(FAR struct spi_dev_s *dev, ubyte ch);
+static void   spi_sndblock(FAR struct spi_dev_s *dev, FAR const ubyte *buffer, size_t buflen);
+static void   spi_recvblock(FAR struct spi_dev_s *dev, FAR ubyte *buffer, size_t buflen);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static const struct spi_ops_s g_spiops =
+{
+  ez80_spiselect,    /* Provided externally by board logic */
+  spi_setfrequency,
+  ez80_spistatus,    /* Provided externally by board logic */
+  spi_sndbyte,
+  spi_sndblock,
+  spi_recvblock,
+};
+
+/* This supports is only a single SPI bus/port.  There you port this to an
+ * architecture with multiple SPI busses/ports, then the following must
+ * become an array with one 'struct spi_dev_s' instance per bus.
+ */
+
+static struct spi_dev_s g_spidev = { &g_spiops };
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: spi_setfrequency
+ *
+ * Description:
+ *   Set the SPI frequency.
+ *
+ * Input Parameters:
+ *   dev -       Device-specific state data
+ *   frequency - The SPI frequency requested
+ *
+ * Returned Value:
+ *   Returns the actual frequency selected
+ *
+ ****************************************************************************/
+
+static uint32 spi_setfrequency(FAR struct spi_dev_s *dev, uint32 frequency)
+{
+  /* We want select divisor to provide the highest frequency (SPIR) that does NOT
+   * exceed the requested frequency.:
+   *
+   *   SPIR <= System Clock Frequency / (2 * BRG)
+   *
+   * So
+   *
+   *   BRG >= System Clock Frequency / (2 * SPIR)
+   */
+ 
+  uint32 brg = ((EZ80_SYS_CLK_FREQ+1)/2 + frequency - 1) / frequency;
+
+  /* "When configured as a Master, the 16-bit divisor value must be between
+   * 0003h and FFFFh, inclusive. When configured as a Slave, the 16-bit
+   * divisor value must be between 0004h and FFFFh, inclusive."
+   */
+
+  if (brg < 3)
+    {
+      brg = 3;
+    }
+  else if (brg > 0xffff)
+    {
+      brg = 0xfff;
+    }
+
+  outp(EZ80_SPI_BRG_L, brg & 0xff);
+  outp(EZ80_SPI_BRG_L, (brg >> 8) & 0xff);
+
+  return ((EZ80_SYS_CLK_FREQ+1)/2 + brg - 1) / brg;
+}
+
+/****************************************************************************
+ * Name: spi_waitspif
+ *
+ * Description:
+ *   Wait for the SPIF bit to be set in the status register signifying the
+ *   the data transfer was finished.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   Status register mode bits
+ *
+ ****************************************************************************/
+
+static ubyte spi_waitspif(void)
+{
+  ubyte status;
+
+  /* Wait for the device to be ready to accept another byte (or for an error
+   * to be reported
+   */
+
+  do
+    {
+      status = inp(EZ80_SPI_SR) & (SPI_SR_SPIF|SPI_SR_WCOL|SPI_SR_MODF);
+    }
+  while (status == 0);
+  return status;
+}
+
+/****************************************************************************
+ * Name: spi_transfer
+ *
+ * Description:
+ *   Send one byte on SPI, return th response
+ *
+ * Input Parameters:
+ *   ch - the byte to send
+ *
+ * Returned Value:
+ *   response
+ *
+ ****************************************************************************/
+
+static ubyte spi_transfer(ubyte ch)
+{
+   ubyte status;
+
+  /* Send the byte, repeating if some error occurs */
+
+  for(;;)
+    {
+      outp(EZ80_SPI_TSR, ch);
+
+      /* Wait for the device to be ready to accept another byte */
+
+      status = spi_waitspif();
+      if ((status & SPI_SR_SPIF) != 0)
+        {
+          return inp(EZ80_SPI_RBR);
+        }
+    }
+}
+
+/****************************************************************************
+ * Name: spi_sndbyte
+ *
+ * Description:
+ *   Send one byte on SPI
+ *
+ * Input Parameters:
+ *   dev - Device-specific state data
+ *   ch -  The byte to send
+ *
+ * Returned Value:
+ *   response
+ *
+ ****************************************************************************/
+
+static ubyte spi_sndbyte(FAR struct spi_dev_s *dev, ubyte ch)
+{
+  return spi_transfer(ch);
+}
+
+/*************************************************************************
+ * Name: spi_sndblock
+ *
+ * Description:
+ *   Send a block of data on SPI
+ *
+ * Input Parameters:
+ *   dev -    Device-specific state data
+ *   buffer - A pointer to the buffer of data to be sent
+ *   buflen - the length of data to send from the buffer
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void spi_sndblock(FAR struct spi_dev_s *dev, FAR const ubyte *buffer, size_t buflen)
+{
+  ubyte response;
+
+  /* Loop while thre are bytes remaining to be sent */
+
+  while (buflen-- > 0)
+    {
+      response = spi_transfer(*buffer++);
+    }
+}
+
+/****************************************************************************
+ * Name: spi_recvblock
+ *
+ * Description:
+ *   Revice a block of data from SPI
+ *
+ * Input Parameters:
+ *   dev -    Device-specific state data
+ *   buffer - A pointer to the buffer in which to recieve data
+ *   buflen - the length of data that can be received in the buffer
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void spi_recvblock(FAR struct spi_dev_s *dev, FAR ubyte *buffer, size_t buflen)
+{
+  ubyte response;
+
+  /* Loop while thre are bytes remaining to be sent */
+
+  while (buflen-- > 0)
+    {
+      *buffer = spi_transfer(0xff);
+    }
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: up_spiinitialize
+ *
+ * Description:
+ *   Initialize common parts the selected SPI port.  Initialization of
+ *   chip select GPIOs must have been performed by board specific logic
+ *   prior to calling this function.  Specifically:  GPIOs should have
+ *   been configured for output, and all chip selects disabled.
+ *
+ *   One GPIO, SS (PB2 on the eZ8F091) is reserved as a chip select.  However,
+ *   If multiple devices on on the bus, then multiple chip selects will be
+ *   required.  Theregore, all GPIO chip management is deferred to board-
+ *   specific logic.
+ *
+ * Input Parameter:
+ *   Port number (for hardware that has mutiple SPI interfaces)
+ *
+ * Returned Value:
+ *   Valid SPI device structre reference on succcess; a NULL on failure
+ *
+ ****************************************************************************/
+
+FAR struct spi_dev_s *up_spiinitialize(int port)
+{
+  ubyte regval;
+
+  /* Only the SPI1 interface is supported */
+
+#ifdef CONFIG_DEBUG
+  if (port != 1)
+    {
+      return NULL;
+    }
+#endif
+
+  /* Disable SPI */
+
+  outp(EZ80_SPI_CTL, 0);
+
+  /* Configure GPIOs.  For the eZ80F91, the pin mapping for the four SPI pins
+   * is:
+   *
+   *  GPIO ALT   MASTER  SLAVE   COMMENT
+   *  ---- ----- ------- ------- ---------------------------------
+   *   PB2 SS    INPUT   INPUT   Managed by board specific logic
+   *   PB3 SCLK  OUTPUT  INPUT
+   *   PB4 MISO  INPUT   OUTPUT
+   *   PB5 MOSI  OUTPUT  INPUT
+   *
+   * Select the alternate function for PB2-5:
+   */
+
+#ifdef CONFIG_ARCH_CHIP_EZ80F91
+  regval  = inp(EZ80_PB_DDR);
+  regval |= GPIOB_SPI_PINSET;
+  outp(EZ80_PB_DDR, regval);
+
+  regval  = inp(EZ80_PB_ALT1);
+  regval &= ~GPIOB_SPI_PINSET;
+  outp(EZ80_PB_ALT1, regval);
+
+  regval  = inp(EZ80_PB_ALT2);
+  regval |= GPIOB_SPI_PINSET;
+  outp(EZ80_PB_ALT2, regval);
+#else
+#  error "Check GPIO initialization for this chip"
+#endif
+
+  /* Set the initial clock frequency for indentification mode < 400kHz */
+
+  spi_setfrequency(NULL, 400000);
+
+  /* Enable the SPI.
+   * NOTE 1: Interrupts are not used in this driver version.
+   * NOTE 2: Certain devices may need changes to SCK polarity settings.
+   */
+
+  outp(EZ80_SPI_CTL, SPI_CTL_SPIEN|SPI_CTL_MASTEREN);
+
+  return &g_spidev;
+}

arch/z80/src/ez80/ez80f91_spi.h

@@ -0,0 +1,125 @@
+/************************************************************************************
+ * arch/z80/src/ez80/ez80f91_spi.h
+ * arch/z80/src/chip/ez80f91_spi.h
+ *
+ *   Copyright (C) 2009 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************************************/
+
+#ifndef __ARCH_Z80_SRC_EZ80_EZ80F91_SPI_H
+#define __ARCH_Z80_SRC_EZ80_EZ80F91_SPI_H
+
+/************************************************************************************
+ * Included Files
+ ************************************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <nuttx/spi.h>
+
+/************************************************************************************
+ * Definitions
+ ************************************************************************************/
+
+/* SPIC Registers  *****************************************************************/
+
+/* Provided in ez80f91.h */
+
+/* SPIC Register Bit Definitions  **************************************************/
+
+/* Baud Rate Generator (BRG) H/L Register Definitions
+ *
+ * No bit definitions -- These two 8-bit registers set the 16-bit BRG divider value
+ */
+
+/*SPI Control (CTL} Register Definitions */
+
+#define SPI_CTL_IRQEN    (1 << 7) /* Bit 7: 1=SPI system interrupt is enabled */
+#define SPI_CTL_SPIEN    (1 << 5) /* Bit 5: 1=SPI is enabled */
+#define SPI_CTL_MASTEREN (1 << 4) /* Bit 4: 1=SPI operates as a master */
+#define SPI_CTL_CPOL     (1 << 3) /* Bit 3: 1=Master SCK pin idles in a high (1) state */
+#define SPI_CTL_CPHA     (1 << 2) /* Bit 2: 1=SS remains Low to transfer any number of data bytes */
+
+/* SR Register Definitions */
+
+#define SPI_SR_SPIF      (1 << 7) /* Bit x: 1=SPI data transfer is finished */
+#define SPI_SR_WCOL      (1 << 6) /* Bit x: 1=SPI write collision is detected*/
+#define SPI_SR_MODF      (1 << 4) /* Bit x: 1=Mode fault (multimaster conflict) is detected */
+
+/* RBR/TSR Register Definitions */
+
+/* No definitions: 8-bit SPI receive/transmit data */
+
+/************************************************************************************
+ * Public Types
+ ************************************************************************************/
+
+/************************************************************************************
+ * Public Data
+ ************************************************************************************/
+
+#ifndef __ASSEMBLY__
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C" {
+#else
+#define EXTERN extern
+#endif /* __cplusplus */
+
+/************************************************************************************
+ * Public Functions
+ ************************************************************************************/
+
+/* The external functions, ez80_spiselect and ez80_spistatus must be provided by
+ * board-specific logic.  The are implementations of the select and status methods
+ * SPI interface defined by struct spi_ops_s (see include/nuttx/spi.h).  All other
+ * methods (including up_spiinitialize()) are provided by common logic.  To use this
+ * common SPI logic on your board:
+ *
+ *   1. Provide ez80_spiselect() and ez80_spistatus() functions in your board-specific 
+ *      logic.  This function will perform chip selection and status operations using
+ *      GPIOs in the way your board is configured.
+ *   2. Add a call to up_spiinitialize() in your low level initialization logic
+ *   3. The handle returned by up_spiinitialize() may then be used to bind the
+ *      SPI driver to higher level logic (e.g., calling  mmcsd_spislotinitializ()
+ *      will bind the SPI driver to the SPI MMC/SD driver.
+ */
+
+EXTERN void ez80_spiselect(FAR struct spi_dev_s *dev, enum spidev_e devid, boolean selected);
+EXTERN ubyte ez80_spistatus(FAR struct spi_dev_s *dev, enum spidev_e devid);
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+#endif /* __ASSEMBLY__ */
+
+#endif  /* __ARCH_Z80_SRC_EZ80_EZ80F91_SPI_H */