[PATCH 3/3] ARM: AT91: Add the ADC to the sam9g20ek board

Maxime Ripard maxime.ripard at free-electrons.com
Fri Dec 2 08:17:57 EST 2011


Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre at atmel.com>
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>

Cc: Patrice Vilchez <patrice.vilchez at atmel.com>
Cc: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
---
 arch/arm/mach-at91/at91sam9260_devices.c |   62 ++++++++++++++++++++++++++++++
 arch/arm/mach-at91/board-sam9g20ek.c     |   13 ++++++
 2 files changed, 75 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mach-at91/at91sam9260_devices.c b/arch/arm/mach-at91/at91sam9260_devices.c
index 39f81f4..012992b 100644
--- a/arch/arm/mach-at91/at91sam9260_devices.c
+++ b/arch/arm/mach-at91/at91sam9260_devices.c
@@ -16,6 +16,8 @@
 #include <linux/platform_device.h>
 #include <linux/i2c-gpio.h>
 
+#include <linux/platform_data/at91_adc.h>
+
 #include <mach/board.h>
 #include <mach/gpio.h>
 #include <mach/cpu.h>
@@ -1312,6 +1314,66 @@ void __init at91_add_device_cf(struct at91_cf_data *data)
 void __init at91_add_device_cf(struct at91_cf_data * data) {}
 #endif
 
+/* --------------------------------------------------------------------
+ *  ADCs
+ * -------------------------------------------------------------------- */
+
+#if defined(CONFIG_IIO_AT91_ADC) || defined(CONFIG_IIO_AT91_ADC_MODULE)
+static struct at91_adc_data adc_data;
+
+static struct resource adc_resources[] = {
+	[0] = {
+		.start	= AT91SAM9260_BASE_ADC,
+		.end	= AT91SAM9260_BASE_ADC + SZ_16K - 1,
+		.flags	= IORESOURCE_MEM,
+	},
+	[1] = {
+		.start	= AT91SAM9260_ID_ADC,
+		.end	= AT91SAM9260_ID_ADC,
+		.flags	= IORESOURCE_IRQ,
+	},
+};
+
+static struct platform_device at91_adc_device = {
+	.name		= "at91_adc",
+	.id		= -1,
+	.dev		= {
+				.platform_data		= &adc_data,
+	},
+	.resource	= adc_resources,
+	.num_resources	= ARRAY_SIZE(adc_resources),
+};
+
+void __init at91_add_device_adc(struct at91_adc_data *data)
+{
+	if (!data)
+		return;
+
+	if (test_bit(0, &data->channels_used))
+		at91_set_A_periph(AT91_PIN_PC0, 0);
+	if (test_bit(1, &data->channels_used))
+		at91_set_A_periph(AT91_PIN_PC1, 0);
+	if (test_bit(2, &data->channels_used))
+		at91_set_A_periph(AT91_PIN_PC2, 0);
+	if (test_bit(3, &data->channels_used))
+		at91_set_A_periph(AT91_PIN_PC3, 0);
+
+	/*
+	 * The electrical characteristics part of the AT91SAM9G20 datasheet
+	 * sets the ADC clock to 5MHz.
+	 */
+	data->adc_clock = 5000000;
+
+	data->num_channels = 4;
+	data->startup_time = 10;
+
+	adc_data = *data;
+	platform_device_register(&at91_adc_device);
+}
+#else
+void __init at91_add_device_adc(struct at91_adc_data *data) {}
+#endif
+
 /* -------------------------------------------------------------------- */
 /*
  * These devices are always present and don't need any board-specific
diff --git a/arch/arm/mach-at91/board-sam9g20ek.c b/arch/arm/mach-at91/board-sam9g20ek.c
index 817f59d..29dae9f 100644
--- a/arch/arm/mach-at91/board-sam9g20ek.c
+++ b/arch/arm/mach-at91/board-sam9g20ek.c
@@ -31,6 +31,8 @@
 #include <linux/regulator/fixed.h>
 #include <linux/regulator/consumer.h>
 
+#include <linux/platform_data/at91_adc.h>
+
 #include <mach/hardware.h>
 #include <asm/setup.h>
 #include <asm/mach-types.h>
@@ -314,6 +316,15 @@ static void __init ek_add_device_buttons(void)
 static void __init ek_add_device_buttons(void) {}
 #endif
 
+/*
+ * ADCs
+ */
+
+static struct at91_adc_data ek_adc_data = {
+	.channels_used = BIT(0) | BIT(1) | BIT(2) | BIT(3),
+	.vref = 3300,
+};
+
 #if defined(CONFIG_REGULATOR_FIXED_VOLTAGE) || defined(CONFIG_REGULATOR_FIXED_VOLTAGE_MODULE)
 static struct regulator_consumer_supply ek_audio_consumer_supplies[] = {
 	REGULATOR_SUPPLY("AVDD", "0-001b"),
@@ -389,6 +400,8 @@ static void __init ek_board_init(void)
 	ek_add_device_gpio_leds();
 	/* Push Buttons */
 	ek_add_device_buttons();
+	/* ADCs */
+	at91_add_device_adc(&ek_adc_data);
 	/* PCK0 provides MCLK to the WM8731 */
 	at91_set_B_periph(AT91_PIN_PC1, 0);
 	/* SSC (for WM8731) */
-- 
1.7.4.1




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