From 97438c6e8344be2e4eb6a87548eaf934a6d71540 Mon Sep 17 00:00:00 2001
From: Anthony DiGirolamo <tonymd@google.com>
Date: Tue, 2 Jul 2024 21:23:04 +0000
Subject: [PATCH] pw_digital_io_rp2040: Add pull up/down resistors to
 Rp2040Config
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Change-Id: Ia9334962b601825c5502cba21256db1e7a1decb1
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/219731
Reviewed-by: Keir Mierle <keir@google.com>
Commit-Queue: Auto-Submit <auto-submit@pigweed-service-accounts.iam.gserviceaccount.com>
Lint: Lint 🤖 <android-build-ayeaye@system.gserviceaccount.com>
Pigweed-Auto-Submit: Anthony DiGirolamo <tonymd@google.com>
Presubmit-Verified: CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com>
---
 pw_digital_io_rp2040/BUILD.gn                 |  8 ++------
 pw_digital_io_rp2040/digital_io.cc            |  2 ++
 pw_digital_io_rp2040/docs.rst                 | 20 ++++++++++++++++++-
 .../public/pw_digital_io_rp2040/digital_io.h  |  2 ++
 4 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/pw_digital_io_rp2040/BUILD.gn b/pw_digital_io_rp2040/BUILD.gn
index 29cc90c46..93a284350 100644
--- a/pw_digital_io_rp2040/BUILD.gn
+++ b/pw_digital_io_rp2040/BUILD.gn
@@ -25,17 +25,13 @@ config("public_includes") {
 pw_source_set("pw_digital_io_rp2040") {
   public_configs = [ ":public_includes" ]
   public = [ "public/pw_digital_io_rp2040/digital_io.h" ]
-  deps = [
-    "$PICO_ROOT/src/common/pico_base",
-    "$PICO_ROOT/src/common/pico_stdlib",
-    "$PICO_ROOT/src/rp2_common/hardware_gpio",
-  ]
   public_deps = [
+    "$PICO_ROOT/src/common/pico_base",
+    "$PICO_ROOT/src/rp2_common/hardware_gpio",
     "$dir_pw_digital_io",
     "$dir_pw_status",
   ]
   sources = [ "digital_io.cc" ]
-  remove_configs = [ "$dir_pw_build:strict_warnings" ]
 }
 
 pw_test("digital_io_test") {
diff --git a/pw_digital_io_rp2040/digital_io.cc b/pw_digital_io_rp2040/digital_io.cc
index 695f4cf84..1db6321ef 100644
--- a/pw_digital_io_rp2040/digital_io.cc
+++ b/pw_digital_io_rp2040/digital_io.cc
@@ -30,6 +30,7 @@ Status Rp2040DigitalIn::DoEnable(bool enable) {
 
   gpio_init(config_.pin);
   gpio_set_dir(config_.pin, GPIO_IN);
+  gpio_set_pulls(config_.pin, config_.enable_pull_up, config_.enable_pull_down);
   return OkStatus();
 }
 
@@ -54,6 +55,7 @@ Status Rp2040DigitalInOut::DoEnable(bool enable) {
 
   gpio_init(config_.pin);
   gpio_set_dir(config_.pin, GPIO_OUT);
+  gpio_set_pulls(config_.pin, config_.enable_pull_up, config_.enable_pull_down);
   return OkStatus();
 }
 
diff --git a/pw_digital_io_rp2040/docs.rst b/pw_digital_io_rp2040/docs.rst
index aca141e35..b171bfcf5 100644
--- a/pw_digital_io_rp2040/docs.rst
+++ b/pw_digital_io_rp2040/docs.rst
@@ -37,6 +37,11 @@ Example code to use GPIO pins:
        .pin = 16,
        .polarity = Polarity::kActiveHigh,
    };
+   constexpr Rp2040Config button_connected_to_ground_config{
+       .pin = 12,
+       .polarity = Polarity::kActiveLow,
+       .enable_pull_up = true,
+   };
 
    // Config output pin:
    Rp2040DigitalInOut out(output_pin_config);
@@ -46,11 +51,24 @@ Example code to use GPIO pins:
    // This pulls pin to ground since the polarity is kActiveLow.
    out.SetState(State::kActive);
 
-   // Config input pin:
+   // Config input pins:
    Rp2040DigitalIn in(input_pin_config);
    in.Enable();
 
+   Rp2040DigitalIn button(button_connected_to_ground_config);
+   button.Enable();
+
    // Get the pin state. Since the polarity is kActiveHigh this will return
    // State::kActive if the pin is high or and State::kInactive if the pin is
    // low (grounded).
    State pin_state = in.GetState();
+
+   auto button_result = button.GetState();
+   if (button_result.ok()) {
+     if (button_result.value() == State::kActive) {
+       PW_LOG_INFO("Button is pressed.");
+     }
+     if (button_result.value() == State::kInactive) {
+       PW_LOG_INFO("Button is released.");
+     }
+   }
diff --git a/pw_digital_io_rp2040/public/pw_digital_io_rp2040/digital_io.h b/pw_digital_io_rp2040/public/pw_digital_io_rp2040/digital_io.h
index 3d4c09e0f..1439980e8 100644
--- a/pw_digital_io_rp2040/public/pw_digital_io_rp2040/digital_io.h
+++ b/pw_digital_io_rp2040/public/pw_digital_io_rp2040/digital_io.h
@@ -24,6 +24,8 @@ namespace pw::digital_io {
 struct Rp2040Config {
   uint16_t pin;
   Polarity polarity;
+  bool enable_pull_up = false;
+  bool enable_pull_down = false;
 
   bool operator==(const Rp2040Config& rhs) const {
     return polarity == rhs.polarity && pin == rhs.pin;