From 7c07bdc08c61a8d751d05a1823911337a50dd7dd Mon Sep 17 00:00:00 2001
From: YoungSoo Shin <shinys000114@gmail.com>
Date: Wed, 2 Jul 2025 09:58:38 +0900
Subject: [PATCH] Revert "ODROID-C5: analog: fix for ODROID-C5"

This reverts commit 4a66eefe5d88ebfe6f7755ae43e9b07e332e926a.
---
 src/linux/analog.c | 48 ++++++++--------------------------------------
 src/linux/gpio.h   |  2 --
 2 files changed, 8 insertions(+), 42 deletions(-)

diff --git a/src/linux/analog.c b/src/linux/analog.c
index 94c97347..7ca1ee2d 100644
--- a/src/linux/analog.c
+++ b/src/linux/analog.c
@@ -14,54 +14,30 @@
 #include "sched.h" // sched_shutdown
 
 // ODROID-C5
-DECL_CONSTANT("ADC_MAX", 1800);
+DECL_CONSTANT("ADC_MAX", 1800); // Assume 12bit adc
 
 #define ANALOG_START (1<<12)
 
 DECL_ENUMERATION_RANGE("pin", "analog0", ANALOG_START, 8);
 
 // ODROID-C5
-#define IIO_PATH "/sys/bus/iio/devices/iio:device0/in_voltage0_raw"
-#define SCALE_PATH "/sys/bus/iio/devices/iio:device0/in_voltage_scale"
-#define OFFSET_PATH "/sys/bus/iio/devices/iio:device0/in_voltage_offset"
+#define IIO_PATH "/sys/bus/iio/devices/iio:device0/in_voltage%d_input"
 
 struct gpio_adc
 gpio_adc_setup(uint32_t pin)
 {
-    struct gpio_adc g;
-	int fd;
-    char buf[64];
-    int ret;
+    char fname[256];
+    snprintf(fname, sizeof(fname), IIO_PATH, pin-ANALOG_START);
 
-	fd = open(SCALE_PATH, O_RDONLY);
-    ret = read(fd, buf, sizeof(buf)-1);
-    if (ret <= 0) {
-        goto fail;
-    }
-    buf[ret] = '\0';
-    g.scale = atof(buf) * 1000;
-    close(fd);
-
-    fd = open(OFFSET_PATH, O_RDONLY);
-    ret = read(fd, buf, sizeof(buf)-1);
-    if (ret <= 0) {
-        goto fail;
-    }
-    buf[ret] = '\0';
-    g.offset = atoi(buf);
-    close(fd);
-
-    fd = open(IIO_PATH, O_RDONLY|O_CLOEXEC);
+    int fd = open(fname, O_RDONLY|O_CLOEXEC);
     if (fd < 0) {
         report_errno("analog open", fd);
         goto fail;
     }
-    ret = set_non_blocking(fd);
+    int ret = set_non_blocking(fd);
     if (ret < 0)
         goto fail;
-
-    g.fd = fd;
-    return g;
+    return (struct gpio_adc){ .fd = fd };
 fail:
     if (fd >= 0)
         close(fd);
@@ -78,7 +54,6 @@ uint16_t
 gpio_adc_read(struct gpio_adc g)
 {
     char buf[64];
-    int voltage;
     int ret = pread(g.fd, buf, sizeof(buf)-1, 0);
     if (ret <= 0) {
         report_errno("analog read", ret);
@@ -86,14 +61,7 @@ gpio_adc_read(struct gpio_adc g)
         return 0;
     }
     buf[ret] = '\0';
-
-	voltage = atoi(buf) + g.offset;
-	voltage = voltage > 0 ? voltage : 0;
-	voltage = voltage * g.scale;
-	voltage = voltage < 1800000 ? voltage : 1800000;
-	voltage /= 1000;
-
-    return voltage;
+    return atoi(buf);
 }
 
 void
diff --git a/src/linux/gpio.h b/src/linux/gpio.h
index 302063b1..d72007c2 100644
--- a/src/linux/gpio.h
+++ b/src/linux/gpio.h
@@ -20,8 +20,6 @@ void gpio_in_reset(struct gpio_in g, int8_t pull_up);
 uint8_t gpio_in_read(struct gpio_in g);
 
 struct gpio_adc {
-    int scale;
-    int offset;
     int fd;
 };
 struct gpio_adc gpio_adc_setup(uint32_t pin);