[PATCH 1/2] EmbeddedPkg: introduce GPIO PPI

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

Introduce a PPI counterpart of the existing 'embedded GPIO' protocol,
so we can manipulate GPIOs from PEI modules. This allows things like
setting the boot mode based on a DIP switch setting.

Note that the naming is slightly awkward, as there is nothing 'embedded'
about a GPIO, but given that the DXE protocol already resides here and
has the 'embedded' prefix, it makes sense to retain uniformity.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 EmbeddedPkg/EmbeddedPkg.dec            |   3 +
 EmbeddedPkg/Include/Ppi/EmbeddedGpio.h | 151 ++++++++++++++++++++
 2 files changed, 154 insertions(+)

diff --git a/EmbeddedPkg/EmbeddedPkg.dec b/EmbeddedPkg/EmbeddedPkg.dec
index 52482af13aeb..cb07d3ece685 100644
--- a/EmbeddedPkg/EmbeddedPkg.dec
+++ b/EmbeddedPkg/EmbeddedPkg.dec
@@ -86,6 +86,9 @@ [Protocols.common]
   gPlatformGpioProtocolGuid = { 0x52ce9845, 0x5af4, 0x43e2, {0xba, 0xfd, 0x23, 0x08, 0x12, 0x54, 0x7a, 0xc2 }}
   gAndroidBootImgProtocolGuid = { 0x9859bb19, 0x407c, 0x4f8b, {0xbc, 0xe1, 0xf8, 0xda, 0x65, 0x65, 0xf4, 0xa5 }}
 
+[Ppis]
+  gEdkiiEmbeddedGpioPpiGuid = { 0x21c3b115, 0x4e0b, 0x470c, { 0x85, 0xc7, 0xe1, 0x05, 0xa5, 0x75, 0xc9, 0x7b }}
+
 [PcdsFeatureFlag.common]
   gEmbeddedTokenSpaceGuid.PcdEmbeddedMacBoot|FALSE|BOOLEAN|0x00000001
   gEmbeddedTokenSpaceGuid.PcdEmbeddedDirCmd|TRUE|BOOLEAN|0x00000002
diff --git a/EmbeddedPkg/Include/Ppi/EmbeddedGpio.h b/EmbeddedPkg/Include/Ppi/EmbeddedGpio.h
new file mode 100644
index 000000000000..d87c860a17fb
--- /dev/null
+++ b/EmbeddedPkg/Include/Ppi/EmbeddedGpio.h
@@ -0,0 +1,151 @@
+/** @file
+
+  Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
+  Copyright (c) 2017, Linaro, Ltd. All rights reserved.<BR>
+
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef __EMBEDDED_GPIO_PPI_H__
+#define __EMBEDDED_GPIO_PPI_H__
+
+//
+// Protocol interface structure
+//
+typedef struct _EMBEDDED_GPIO_PPI   EMBEDDED_GPIO_PPI;
+
+//
+// Data Types
+//
+typedef UINTN EMBEDDED_GPIO_PIN;
+
+#define GPIO(Port, Pin) ((EMBEDDED_GPIO_PIN)(((Port) << (16)) | (Pin)))
+#define GPIO_PIN(x)     ((EMBEDDED_GPIO_PIN)(x) & (0xFFFF))
+#define GPIO_PORT(x)    ((EMBEDDED_GPIO_PIN)(x) >> (16))
+
+typedef enum {
+  GPIO_MODE_INPUT                 = 0x00,
+  GPIO_MODE_OUTPUT_0              = 0x0E,
+  GPIO_MODE_OUTPUT_1              = 0x0F,
+  GPIO_MODE_SPECIAL_FUNCTION_2    = 0x02,
+  GPIO_MODE_SPECIAL_FUNCTION_3    = 0x03,
+  GPIO_MODE_SPECIAL_FUNCTION_4    = 0x04,
+  GPIO_MODE_SPECIAL_FUNCTION_5    = 0x05,
+  GPIO_MODE_SPECIAL_FUNCTION_6    = 0x06,
+  GPIO_MODE_SPECIAL_FUNCTION_7    = 0x07
+} EMBEDDED_GPIO_MODE;
+
+typedef enum {
+  GPIO_PULL_NONE,
+  GPIO_PULL_UP,
+  GPIO_PULL_DOWN
+} EMBEDDED_GPIO_PULL;
+
+//
+// Function Prototypes
+//
+
+/**
+
+  Gets the state of a GPIO pin
+
+  @param This                   Pointer to protocol
+  @param Gpio                   Which pin to read
+  @param Value                  State of the pin
+
+  @retval EFI_SUCCESS           GPIO state returned in Value
+  @retval EFI_INVALID_PARAMETER Value is NULL
+  @retval EFI_NOT_FOUND         Pin does not exit
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EMBEDDED_GPIO_GET) (
+  IN  EMBEDDED_GPIO_PPI     *This,
+  IN  EMBEDDED_GPIO_PIN     Gpio,
+  OUT UINTN                 *Value
+  );
+
+/**
+
+  Sets the state of a GPIO pin
+
+  @param This                   Pointer to protocol
+  @param Gpio                   Which pin to modify
+  @param Mode                   Mode to set
+
+  @retval EFI_SUCCESS           GPIO set as requested
+  @retval EFI_INVALID_PARAMETER Invalid mode
+  @retval EFI_NOT_FOUND         Pin does not exit
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EMBEDDED_GPIO_SET) (
+  IN EMBEDDED_GPIO_PPI      *This,
+  IN EMBEDDED_GPIO_PIN      Gpio,
+  IN EMBEDDED_GPIO_MODE     Mode
+  );
+
+
+/**
+
+  Gets the mode (function) of a GPIO pin
+
+  @param This                   Pointer to protocol
+  @param Gpio                   Which pin
+  @param Mode                   Pointer to output mode value
+
+  @retval EFI_SUCCESS           Mode value retrieved
+  @retval EFI_INVALID_PARAMETER Mode is NULL
+  @retval EFI_NOT_FOUND         Pin does not exit
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EMBEDDED_GPIO_GET_MODE) (
+  IN  EMBEDDED_GPIO_PPI     *This,
+  IN  EMBEDDED_GPIO_PIN     Gpio,
+  OUT EMBEDDED_GPIO_MODE    *Mode
+  );
+
+
+/**
+
+  Sets the pull-up / pull-down resistor of a GPIO pin
+
+  @param This                   Pointer to PPI
+  @param Gpio                   Port/pin index
+  @param Pull                   The pullup/pulldown mode to set
+
+  @retval EFI_SUCCESS           Mode was set
+  @retval EFI_NOT_FOUND         Pin does not exist
+  @retval EFI_UNSUPPORTED       Action not supported
+
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EMBEDDED_GPIO_SET_PULL) (
+  IN  EMBEDDED_GPIO_PPI     *This,
+  IN  EMBEDDED_GPIO_PIN     Gpio,
+  IN  EMBEDDED_GPIO_PULL    Direction
+  );
+
+
+struct _EMBEDDED_GPIO_PPI {
+  EMBEDDED_GPIO_GET         Get;
+  EMBEDDED_GPIO_SET         Set;
+  EMBEDDED_GPIO_GET_MODE    GetMode;
+  EMBEDDED_GPIO_SET_PULL    SetPull;
+};
+
+extern EFI_GUID gEmbeddedGpioPpiGuid;
+
+#endif
-- 
2.11.0