sam3x8e: Move adc support to a new adc.c file

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 1 insertions, 84 deletions

diff --git a/src/sam3x8e/gpio.c b/src/sam3x8e/gpio.c
index b12dc447..f48c5f0d 100644
--- a/src/sam3x8e/gpio.c
+++ b/src/sam3x8e/gpio.c
@@ -1,11 +1,9 @@
 // GPIO functions on sam3x8e
 //
-// Copyright (C) 2016,2017  Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2016-2018  Kevin O'Connor <kevin@koconnor.net>
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
-#include <stdint.h> // uint32_t
-#include "autoconf.h" // CONFIG_CLOCK_FREQ
 #include "board/irq.h" // irq_save
 #include "command.h" // shutdown
 #include "compiler.h" // ARRAY_SIZE
@@ -133,84 +131,3 @@ gpio_in_read(struct gpio_in g)
     Pio *regs = g.regs;
     return !!(regs->PIO_PDSR & g.bit);
 }
-
-
-/****************************************************************
- * Analog to Digital Converter (ADC) pins
- ****************************************************************/
-
-static const uint8_t adc_pins[] = {
-    GPIO('A', 2), GPIO('A', 3), GPIO('A', 4), GPIO('A', 6),
-    GPIO('A', 22), GPIO('A', 23), GPIO('A', 24), GPIO('A', 16),
-    GPIO('B', 12), GPIO('B', 13), GPIO('B', 17), GPIO('B', 18),
-    GPIO('B', 19), GPIO('B', 20)
-};
-
-#define ADC_FREQ_MAX 20000000
-DECL_CONSTANT(ADC_MAX, 4095);
-
-struct gpio_adc
-gpio_adc_setup(uint8_t pin)
-{
-    // Find pin in adc_pins table
-    int chan;
-    for (chan=0; ; chan++) {
-        if (chan >= ARRAY_SIZE(adc_pins))
-            shutdown("Not a valid ADC pin");
-        if (adc_pins[chan] == pin)
-            break;
-    }
-
-    if (!(PMC->PMC_PCSR1 & (1 << (ID_ADC-32)))) {
-        // Setup ADC
-        PMC->PMC_PCER1 = 1 << (ID_ADC-32);
-        uint32_t prescal = SystemCoreClock / (2 * ADC_FREQ_MAX) - 1;
-        ADC->ADC_MR = (ADC_MR_PRESCAL(prescal)
-                       | ADC_MR_STARTUP_SUT768
-                       | ADC_MR_TRANSFER(1));
-    }
-    return (struct gpio_adc){ .bit = 1 << chan };
-}
-
-// Try to sample a value. Returns zero if sample ready, otherwise
-// returns the number of clock ticks the caller should wait before
-// retrying this function.
-uint32_t
-gpio_adc_sample(struct gpio_adc g)
-{
-    uint32_t chsr = ADC->ADC_CHSR & 0xffff;
-    if (!chsr) {
-        // Start sample
-        ADC->ADC_CHER = g.bit;
-        ADC->ADC_CR = ADC_CR_START;
-        goto need_delay;
-    }
-    if (chsr != g.bit)
-        // Sampling in progress on another channel
-        goto need_delay;
-    if (!(ADC->ADC_ISR & ADC_ISR_DRDY))
-        // Conversion still in progress
-        goto need_delay;
-    // Conversion ready
-    return 0;
-need_delay:
-    return ADC_FREQ_MAX * 1000ULL / CONFIG_CLOCK_FREQ;
-}
-
-// Read a value; use only after gpio_adc_sample() returns zero
-uint16_t
-gpio_adc_read(struct gpio_adc g)
-{
-    ADC->ADC_CHDR = g.bit;
-    return ADC->ADC_LCDR;
-}
-
-// Cancel a sample that may have been started with gpio_adc_sample()
-void
-gpio_adc_cancel_sample(struct gpio_adc g)
-{
-    irqstatus_t flag = irq_save();
-    if ((ADC->ADC_CHSR & 0xffff) == g.bit)
-        gpio_adc_read(g);
-    irq_restore(flag);
-}