From 8a5926b5e3a6fce70f46bd91dbe35be15bf4a267 Mon Sep 17 00:00:00 2001
From: Woazboat <f.kargl@posteo.de>
Date: Sat, 3 Aug 2019 03:51:49 +0200
Subject: [PATCH] refactor(portexpander): defines for portexpander commands +
common read/write functions
---
lib/card10/portexpander.c | 76 ++++++++++++++++++++++++++-------------
1 file changed, 51 insertions(+), 25 deletions(-)
diff --git a/lib/card10/portexpander.c b/lib/card10/portexpander.c
index 920d8dfa..ee3ac3da 100644
--- a/lib/card10/portexpander.c
+++ b/lib/card10/portexpander.c
@@ -7,17 +7,57 @@
#include <string.h>
#include <stdbool.h>
+// PCAL6408A I2C port expander
+
static bool detected = false;
static uint8_t output_state;
+/* clang-format off */
+#define PE_ADDR 0x42
+
+#define PE_C_INPUT_PORT 0x00
+#define PE_C_OUTPUT_PORT 0x01
+#define PE_C_POLARITY_INV 0x02
+#define PE_C_CONFIG 0x03
+#define PE_C_OUTPUT_DRIVE_STR_0 0x40
+#define PE_C_OUTPUT_DRIVE_STR_1 0x41
+#define PE_C_INPUT_LATCH 0x42
+#define PE_C_PULL_ENABLE 0x43
+#define PE_C_PULL_SEL 0x44
+#define PE_C_INT_MASK 0x45
+#define PE_C_INT_STATUS 0x46
+#define PE_C_OUTPUT_PORT_CONFIG 0x4F
+
+#define PE_CONFIG_OUT 0
+#define PE_CONFIG_IN 1
+
+#define PE_PULL_DOWN 0
+#define PE_PULL_UP 1
+
+#define PE_OUT_PUSH_PULL 0
+#define PE_OUT_OPEN_DRAIN 1
+/* clang-format on */
+
+#define PE_INPUT_MASK ((uint8_t)0b01101000) // 3, 5, 6 = input
+
+static int portexpander_write(uint8_t command, uint8_t data)
+{
+ uint8_t i2c_data[2] = { command, data };
+ return I2C_MasterWrite(MXC_I2C1_BUS0, PE_ADDR, i2c_data, 2, 0);
+}
+
+static int portexpander_read(uint8_t command, uint8_t *data)
+{
+ I2C_MasterWrite(MXC_I2C1_BUS0, PE_ADDR, &command, 1, 1);
+ return I2C_MasterRead(MXC_I2C1_BUS0, PE_ADDR, data, 1, 0);
+}
+
void portexpander_init(void)
{
- uint8_t addr = 0x21;
int ret;
- // Enable pull-ups for buttons
- uint8_t command[] = { 0x43, 0x68 };
- ret = I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
+ // Enable pull-ups for buttons (type defaults to pull-up)
+ ret = portexpander_write(PE_C_PULL_ENABLE, PE_INPUT_MASK);
if (ret != 2) {
printf("portexpander NOT detected\n");
@@ -27,31 +67,22 @@ void portexpander_init(void)
detected = true;
// Set _all_ outputs to open-drain to support the high side p-channel transistors.
- command[0] = 0x4F;
- command[1] = 0x01;
- I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
+ portexpander_write(PE_C_OUTPUT_PORT_CONFIG, PE_OUT_OPEN_DRAIN);
// Enable outputs for the transistors, the LED and the LCD reset
- command[0] = 0x03;
- command[1] = 0x68;
- I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
+ portexpander_write(PE_C_CONFIG, PE_INPUT_MASK);
// Set outputs to high (i.e. open-drain)
- output_state = 0x97;
- command[0] = 0x01;
- command[1] = output_state;
- I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
+ output_state = ~PE_INPUT_MASK;
+ portexpander_write(PE_C_OUTPUT_PORT, output_state);
}
uint8_t portexpander_get(void)
{
- uint8_t addr = 0x21;
- uint8_t command[] = { 0x00 };
- uint8_t buf = 0xFF;
+ uint8_t buf = 0xFF;
if (detected) {
- I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 1, 1);
- I2C_MasterRead(MXC_I2C1_BUS0, addr << 1, &buf, 1, 0);
+ portexpander_read(PE_C_INPUT_PORT, &buf);
}
return buf;
@@ -64,9 +95,6 @@ bool portexpander_detected(void)
void portexpander_set(uint8_t pin, uint8_t value)
{
- uint8_t addr = 0x21;
- uint8_t command[2];
-
if (detected && pin < 8) {
if (value) {
output_state |= (1 << pin);
@@ -74,8 +102,6 @@ void portexpander_set(uint8_t pin, uint8_t value)
output_state &= ~(1 << pin);
}
- command[0] = 0x01;
- command[1] = output_state;
- I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
+ portexpander_write(PE_C_OUTPUT_PORT, output_state);
}
}
--
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