Change 4 chip limit on sn74hc595 to 256 (#4108)

esphome/components/sn74hc595/__init__.py

@@ -17,7 +17,9 @@ MULTI_CONF = True
 sn74hc595_ns = cg.esphome_ns.namespace("sn74hc595")
 
 SN74HC595Component = sn74hc595_ns.class_("SN74HC595Component", cg.Component)
-SN74HC595GPIOPin = sn74hc595_ns.class_("SN74HC595GPIOPin", cg.GPIOPin)
+SN74HC595GPIOPin = sn74hc595_ns.class_(
+    "SN74HC595GPIOPin", cg.GPIOPin, cg.Parented.template(SN74HC595Component)
+)
 
 CONF_SN74HC595 = "sn74hc595"
 CONF_LATCH_PIN = "latch_pin"
@@ -30,7 +32,7 @@ CONFIG_SCHEMA = cv.Schema(
         cv.Required(CONF_CLOCK_PIN): pins.gpio_output_pin_schema,
         cv.Required(CONF_LATCH_PIN): pins.gpio_output_pin_schema,
         cv.Optional(CONF_OE_PIN): pins.gpio_output_pin_schema,
-        cv.Optional(CONF_SR_COUNT, default=1): cv.int_range(1, 4),
+        cv.Optional(CONF_SR_COUNT, default=1): cv.int_range(min=1, max=256),
     }
 ).extend(cv.COMPONENT_SCHEMA)
 
@@ -60,7 +62,7 @@ SN74HC595_PIN_SCHEMA = cv.All(
     {
         cv.GenerateID(): cv.declare_id(SN74HC595GPIOPin),
         cv.Required(CONF_SN74HC595): cv.use_id(SN74HC595Component),
-        cv.Required(CONF_NUMBER): cv.int_range(min=0, max=31),
+        cv.Required(CONF_NUMBER): cv.int_range(min=0, max=2048, max_included=False),
         cv.Optional(CONF_MODE, default={}): cv.All(
             {
                 cv.Optional(CONF_OUTPUT, default=True): cv.All(
@@ -76,10 +78,8 @@ SN74HC595_PIN_SCHEMA = cv.All(
 @pins.PIN_SCHEMA_REGISTRY.register(CONF_SN74HC595, SN74HC595_PIN_SCHEMA)
 async def sn74hc595_pin_to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
-    parent = await cg.get_variable(config[CONF_SN74HC595])
-    cg.add(var.set_parent(parent))
+    await cg.register_parented(var, config[CONF_SN74HC595])
 
-    num = config[CONF_NUMBER]
-    cg.add(var.set_pin(num))
+    cg.add(var.set_pin(config[CONF_NUMBER]))
     cg.add(var.set_inverted(config[CONF_INVERTED]))
     return var

esphome/components/sn74hc595/sn74hc595.cpp

@@ -28,24 +28,21 @@ void SN74HC595Component::setup() {
 
 void SN74HC595Component::dump_config() { ESP_LOGCONFIG(TAG, "SN74HC595:"); }
 
-bool SN74HC595Component::digital_read_(uint8_t pin) { return this->output_bits_ >> pin; }
-
-void SN74HC595Component::digital_write_(uint8_t pin, bool value) {
-  uint32_t mask = 1UL << pin;
-  this->output_bits_ &= ~mask;
-  if (value)
-    this->output_bits_ |= mask;
+void SN74HC595Component::digital_write_(uint16_t pin, bool value) {
+  if (pin >= this->sr_count_ * 8) {
+    ESP_LOGE(TAG, "Pin %u is out of range! Maximum pin number with %u chips in series is %u", pin, this->sr_count_,
+             (this->sr_count_ * 8) - 1);
+    return;
+  }
+  this->output_bits_[pin] = value;
   this->write_gpio_();
 }
 
-bool SN74HC595Component::write_gpio_() {
-  for (int i = this->sr_count_ - 1; i >= 0; i--) {
-    uint8_t data = (uint8_t)(this->output_bits_ >> (8 * i) & 0xff);
-    for (int j = 0; j < 8; j++) {
-      this->data_pin_->digital_write(data & (1 << (7 - j)));
-      this->clock_pin_->digital_write(true);
-      this->clock_pin_->digital_write(false);
-    }
+void SN74HC595Component::write_gpio_() {
+  for (auto bit = this->output_bits_.rbegin(); bit != this->output_bits_.rend(); bit++) {
+    this->data_pin_->digital_write(*bit);
+    this->clock_pin_->digital_write(true);
+    this->clock_pin_->digital_write(false);
   }
 
   // pulse latch to activate new values
@@ -56,8 +53,6 @@ bool SN74HC595Component::write_gpio_() {
   if (this->have_oe_pin_) {
     this->oe_pin_->digital_write(false);
   }
-
-  return true;
 }
 
 float SN74HC595Component::get_setup_priority() const { return setup_priority::IO; }

esphome/components/sn74hc595/sn74hc595.h

@@ -2,6 +2,9 @@
 
 #include "esphome/core/component.h"
 #include "esphome/core/hal.h"
+#include "esphome/core/helpers.h"
+
+#include <vector>
 
 namespace esphome {
 namespace sn74hc595 {
@@ -21,13 +24,15 @@ class SN74HC595Component : public Component {
     oe_pin_ = pin;
     have_oe_pin_ = true;
   }
-  void set_sr_count(uint8_t count) { sr_count_ = count; }
+  void set_sr_count(uint8_t count) {
+    sr_count_ = count;
+    this->output_bits_.resize(count * 8);
+  }
 
  protected:
   friend class SN74HC595GPIOPin;
-  bool digital_read_(uint8_t pin);
-  void digital_write_(uint8_t pin, bool value);
-  bool write_gpio_();
+  void digital_write_(uint16_t pin, bool value);
+  void write_gpio_();
 
   GPIOPin *data_pin_;
   GPIOPin *clock_pin_;
@@ -35,11 +40,11 @@ class SN74HC595Component : public Component {
   GPIOPin *oe_pin_;
   uint8_t sr_count_;
   bool have_oe_pin_{false};
-  uint32_t output_bits_{0x00};
+  std::vector<bool> output_bits_;
 };
 
 /// Helper class to expose a SC74HC595 pin as an internal output GPIO pin.
-class SN74HC595GPIOPin : public GPIOPin {
+class SN74HC595GPIOPin : public GPIOPin, public Parented<SN74HC595Component> {
  public:
   void setup() override {}
   void pin_mode(gpio::Flags flags) override {}
@@ -47,13 +52,11 @@ class SN74HC595GPIOPin : public GPIOPin {
   void digital_write(bool value) override;
   std::string dump_summary() const override;
 
-  void set_parent(SN74HC595Component *parent) { parent_ = parent; }
-  void set_pin(uint8_t pin) { pin_ = pin; }
+  void set_pin(uint16_t pin) { pin_ = pin; }
   void set_inverted(bool inverted) { inverted_ = inverted; }
 
  protected:
-  SN74HC595Component *parent_;
-  uint8_t pin_;
+  uint16_t pin_;
   bool inverted_;
 };