[PATCHv4] Add ADC driver for Atmel G20, G45 and X5 boards

[PATCHv4] Add ADC driver for Atmel G20, G45 and X5 boards

[Maxime Ripard]

Hi all,

Here is another round of ADC patches based on reviews from Nicolas Ferre.
Nothing really fancy here, mostly changed the compatible string to at91sam9260
since the g20 and the 9260 both share the same ADC, and various small fixes,
typos, etc.

Thanks,
Maxime

[PATCHv4] Add ADC driver for Atmel G20, G45 and X5 boards

[Maxime Ripard]

Hi all,

Here is another round of ADC patches based on reviews from Nicolas Ferre.
Nothing really fancy here, mostly changed the compatible string to at91sam9260
since the g20 and the 9260 both share the same ADC, and various small fixes,
typos, etc.

Thanks,
Maxime

[PATCH 1/9] ARM: AT91: Add platform data for the AT91 ADCs

[Maxime Ripard]

The AT91 SoCs often embeds an ADC. This patch adds the needed
platform data to specify the informations required by the driver
to work properly.

For now, we only need the reference voltage and which channels
are available on the board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 include/linux/platform_data/at91_adc.h |   61 ++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 include/linux/platform_data/at91_adc.h

diff --git a/include/linux/platform_data/at91_adc.h b/include/linux/platform_data/at91_adc.h
new file mode 100644
index 0000000..f9e2f00
--- /dev/null
+++ b/include/linux/platform_data/at91_adc.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2011 Free Electrons
+ *
+ * Licensed under the GPLv2 or later.
+ */
+
+#ifndef _AT91_ADC_H_
+#define _AT91_ADC_H_
+
+/**
+ * struct at91_adc_reg_desc - Various informations relative to registers
+ * @channel_base:	Base address for the channel data registers
+ * @drdy_mask:		Mask of the DRDY field in the relevant registers
+			(Interruptions registers mostly)
+ * @status_register:	Address of the Interrupt Status Register
+ * @trigger_register:	Address of the Trigger setup register
+ */
+struct at91_adc_reg_desc {
+	u8	channel_base;
+	u32	drdy_mask;
+	u8	status_register;
+	u8	trigger_register;
+};
+
+/**
+ * struct at91_adc_trigger - description of triggers
+ * @name:		name of the trigger advertised to the user
+ * @value:		value to set in the ADC's mode register to enable
+			the trigger
+ * @is_external:	is the trigger relies on an external pin ?
+ */
+struct at91_adc_trigger {
+	const char	*name;
+	u8		value;
+	bool		is_external;
+};
+
+/**
+ * struct at91_adc_data - platform data for ADC driver
+ * @channels_used:		channels in use on the board as a bitmask
+ * @num_channels:		global number of channels available on the board
+ * @registers:			Registers definition on the board
+ * @startup_time:		startup time of the ADC in microseconds
+ * @trigger_list:		Triggers available in the ADC
+ * @trigger_number:		Number of triggers available in the ADC
+ * @use_external_triggers:	does the board has external triggers availables
+ * @vref:			Reference voltage for the ADC in millivolts
+ */
+struct at91_adc_data {
+	unsigned long			channels_used;
+	u8				num_channels;
+	struct at91_adc_reg_desc	*registers;
+	u8				startup_time;
+	struct at91_adc_trigger		*trigger_list;
+	u8				trigger_number;
+	bool				use_external_triggers;
+	u16				vref;
+};
+
+extern void __init at91_add_device_adc(struct at91_adc_data *data);
+#endif
-- 
1.7.9.5

[PATCH 1/9] ARM: AT91: Add platform data for the AT91 ADCs

[Maxime Ripard]

The AT91 SoCs often embeds an ADC. This patch adds the needed
platform data to specify the informations required by the driver
to work properly.

For now, we only need the reference voltage and which channels
are available on the board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 include/linux/platform_data/at91_adc.h |   61 ++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 include/linux/platform_data/at91_adc.h

diff --git a/include/linux/platform_data/at91_adc.h b/include/linux/platform_data/at91_adc.h
new file mode 100644
index 0000000..f9e2f00
--- /dev/null
+++ b/include/linux/platform_data/at91_adc.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2011 Free Electrons
+ *
+ * Licensed under the GPLv2 or later.
+ */
+
+#ifndef _AT91_ADC_H_
+#define _AT91_ADC_H_
+
+/**
+ * struct at91_adc_reg_desc - Various informations relative to registers
+ * @channel_base:	Base address for the channel data registers
+ * @drdy_mask:		Mask of the DRDY field in the relevant registers
+			(Interruptions registers mostly)
+ * @status_register:	Address of the Interrupt Status Register
+ * @trigger_register:	Address of the Trigger setup register
+ */
+struct at91_adc_reg_desc {
+	u8	channel_base;
+	u32	drdy_mask;
+	u8	status_register;
+	u8	trigger_register;
+};
+
+/**
+ * struct at91_adc_trigger - description of triggers
+ * @name:		name of the trigger advertised to the user
+ * @value:		value to set in the ADC's mode register to enable
+			the trigger
+ * @is_external:	is the trigger relies on an external pin ?
+ */
+struct at91_adc_trigger {
+	const char	*name;
+	u8		value;
+	bool		is_external;
+};
+
+/**
+ * struct at91_adc_data - platform data for ADC driver
+ * @channels_used:		channels in use on the board as a bitmask
+ * @num_channels:		global number of channels available on the board
+ * @registers:			Registers definition on the board
+ * @startup_time:		startup time of the ADC in microseconds
+ * @trigger_list:		Triggers available in the ADC
+ * @trigger_number:		Number of triggers available in the ADC
+ * @use_external_triggers:	does the board has external triggers availables
+ * @vref:			Reference voltage for the ADC in millivolts
+ */
+struct at91_adc_data {
+	unsigned long			channels_used;
+	u8				num_channels;
+	struct at91_adc_reg_desc	*registers;
+	u8				startup_time;
+	struct at91_adc_trigger		*trigger_list;
+	u8				trigger_number;
+	bool				use_external_triggers;
+	u16				vref;
+};
+
+extern void __init at91_add_device_adc(struct at91_adc_data *data);
+#endif
-- 
1.7.9.5

[PATCH 2/9] ARM: AT91: IIO: Add AT91 ADC driver.

[Maxime Ripard]

Add the ADC driver for Atmel's AT91SAM9G20-EK, AT91SAM9M10G45-EK
and AT91SAM9X5 family boards.

It has support for both software and hardware triggers.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 drivers/iio/Kconfig        |    2 +
 drivers/iio/Makefile       |    2 +
 drivers/iio/adc/Kconfig    |   16 ++
 drivers/iio/adc/Makefile   |    5 +
 drivers/iio/adc/at91_adc.c |  673 ++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 698 insertions(+)
 create mode 100644 drivers/iio/adc/Kconfig
 create mode 100644 drivers/iio/adc/Makefile
 create mode 100644 drivers/iio/adc/at91_adc.c

diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
index 3ab7d48..47e0920 100644
--- a/drivers/iio/Kconfig
+++ b/drivers/iio/Kconfig
@@ -48,4 +48,6 @@ config IIO_CONSUMERS_PER_TRIGGER
 	This value controls the maximum number of consumers that a
 	given trigger may handle. Default is 2.
 
+source "drivers/iio/adc/Kconfig"
+
 endif # IIO
diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
index d5fc57d..eb926a2 100644
--- a/drivers/iio/Makefile
+++ b/drivers/iio/Makefile
@@ -8,3 +8,5 @@ industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o
 industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o
 
 obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o
+
+obj-y += adc/
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
new file mode 100644
index 0000000..9a0df81
--- /dev/null
+++ b/drivers/iio/adc/Kconfig
@@ -0,0 +1,16 @@
+#
+# ADC drivers
+#
+menu "Analog to digital converters"
+
+config AT91_ADC
+	tristate "Atmel AT91 ADC"
+	depends on ARCH_AT91
+	select IIO_BUFFER
+	select IIO_KFIFO_BUF
+	select IIO_TRIGGER
+	select SYSFS
+	help
+	  Say yes here to build support for Atmel AT91 ADC.
+
+endmenu
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
new file mode 100644
index 0000000..b62d488
--- /dev/null
+++ b/drivers/iio/adc/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for IIO ADC drivers
+#
+
+obj-$(CONFIG_AT91_ADC) += at91_adc.o
\ No newline at end of file
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
new file mode 100644
index 0000000..e5d73b1
--- /dev/null
+++ b/drivers/iio/adc/at91_adc.c
@@ -0,0 +1,673 @@
+/*
+ * Driver for the ADC present in the Atmel AT91 evaluation boards.
+ *
+ * Copyright 2011 Free Electrons
+ *
+ * Licensed under the GPLv2 or later.
+ */
+
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+
+#include <linux/platform_data/at91_adc.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+
+#include <mach/at91_adc.h>
+
+#define AT91_ADC_CHAN(st, ch) \
+	(st->registers->channel_base + (ch * 4))
+#define at91_adc_readl(st, reg) \
+	(readl_relaxed(st->reg_base + reg))
+#define at91_adc_writel(st, reg, val) \
+	(writel_relaxed(val, st->reg_base + reg))
+
+struct at91_adc_state {
+	struct clk		*adc_clk;
+	u16			*buffer;
+	unsigned long		channels_mask;
+	struct clk		*clk;
+	bool			done;
+	int			irq;
+	bool			irq_enabled;
+	u16			last_value;
+	struct mutex		lock;
+	u8			num_channels;
+	void __iomem		*reg_base;
+	struct at91_adc_reg_desc *registers;
+	u8			startup_time;
+	struct iio_trigger	**trig;
+	struct at91_adc_trigger	*trigger_list;
+	u32			trigger_number;
+	bool			use_external;
+	u32			vref_mv;
+	wait_queue_head_t	wq_data_avail;
+};
+
+static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *idev = pf->indio_dev;
+	struct at91_adc_state *st = iio_priv(idev);
+	struct iio_buffer *buffer = idev->buffer;
+	int i, j = 0;
+
+	for (i = 0; i < idev->masklength; i++) {
+		if (!test_bit(i, idev->active_scan_mask))
+			continue;
+		st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, i));
+		j++;
+	}
+
+	if (idev->scan_timestamp) {
+		s64 *timestamp = (s64 *)((u8 *)st->buffer +
+					ALIGN(j, sizeof(s64)));
+		*timestamp = pf->timestamp;
+	}
+
+	buffer->access->store_to(buffer, (u8 *)st->buffer, pf->timestamp);
+
+	iio_trigger_notify_done(idev->trig);
+	st->irq_enabled = true;
+
+	/* Needed to ACK the DRDY interruption */
+	at91_adc_readl(st, AT91_ADC_LCDR);
+
+	enable_irq(st->irq);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t at91_adc_eoc_trigger(int irq, void *private)
+{
+	struct iio_dev *idev = private;
+	struct at91_adc_state *st = iio_priv(idev);
+	u32 status = at91_adc_readl(st, st->registers->status_register);
+
+	if (!(status & st->registers->drdy_mask))
+		return IRQ_HANDLED;
+
+	if (iio_buffer_enabled(idev)) {
+		disable_irq_nosync(irq);
+		st->irq_enabled = false;
+		iio_trigger_poll(idev->trig, iio_get_time_ns());
+	} else {
+		st->last_value = at91_adc_readl(st, AT91_ADC_LCDR);
+		st->done = true;
+		wake_up_interruptible(&st->wq_data_avail);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int at91_adc_channel_init(struct iio_dev *idev)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	struct iio_chan_spec *chan_array, *timestamp;
+	int bit, idx = 0;
+
+	idev->num_channels = bitmap_weight(&st->channels_mask,
+					   st->num_channels) + 1;
+
+	chan_array = devm_kzalloc(&idev->dev,
+				  ((idev->num_channels + 1) *
+					sizeof(struct iio_chan_spec)),
+				  GFP_KERNEL);
+
+	if (!chan_array)
+		return -ENOMEM;
+
+	for_each_set_bit(bit, &st->channels_mask, st->num_channels) {
+		struct iio_chan_spec *chan = chan_array + idx;
+
+		chan->type = IIO_VOLTAGE;
+		chan->indexed = 1;
+		chan->channel = bit;
+		chan->scan_index = idx;
+		chan->scan_type.sign = 'u';
+		chan->scan_type.realbits = 10;
+		chan->scan_type.storagebits = 16;
+		chan->info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT |
+			IIO_CHAN_INFO_RAW_SEPARATE_BIT;
+		idx++;
+	}
+	timestamp = chan_array + idx;
+
+	timestamp->type = IIO_TIMESTAMP;
+	timestamp->channel = -1;
+	timestamp->scan_index = idx;
+	timestamp->scan_type.sign = 's';
+	timestamp->scan_type.realbits = 64;
+	timestamp->scan_type.storagebits = 64;
+
+	idev->channels = chan_array;
+	return idev->num_channels;
+}
+
+static u8 at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
+					     struct at91_adc_trigger *triggers,
+					     const char *trigger_name)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	u8 value = 0;
+	int i;
+
+	for (i = 0; i < st->trigger_number; i++) {
+		char *name = kasprintf(GFP_KERNEL,
+				"%s-dev%d-%s",
+				idev->name,
+				idev->id,
+				triggers[i].name);
+		if (!name)
+			return -ENOMEM;
+
+		if (strcmp(trigger_name, name) == 0) {
+			value = triggers[i].value;
+			kfree(name);
+			break;
+		}
+
+		kfree(name);
+	}
+
+	return value;
+}
+
+static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
+{
+	struct iio_dev *idev = trig->private_data;
+	struct at91_adc_state *st = iio_priv(idev);
+	struct iio_buffer *buffer = idev->buffer;
+	struct at91_adc_reg_desc *reg = st->registers;
+	u32 status = at91_adc_readl(st, reg->trigger_register);
+	u8 value;
+	u8 bit;
+
+	value = at91_adc_get_trigger_value_by_name(idev,
+						   st->trigger_list,
+						   idev->trig->name);
+	if (value == 0)
+		return -EINVAL;
+
+	if (state) {
+		st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL);
+		if (st->buffer == NULL)
+			return -ENOMEM;
+
+		at91_adc_writel(st, reg->trigger_register,
+				status | value);
+
+		for_each_set_bit(bit, buffer->scan_mask,
+				 st->num_channels) {
+			struct iio_chan_spec const *chan = idev->channels + bit;
+			at91_adc_writel(st, AT91_ADC_CHER,
+					AT91_ADC_CH(chan->channel));
+		}
+
+		at91_adc_writel(st, AT91_ADC_IER, reg->drdy_mask);
+
+	} else {
+		at91_adc_writel(st, AT91_ADC_IDR, reg->drdy_mask);
+
+		at91_adc_writel(st, reg->trigger_register,
+				status & ~value);
+
+		for_each_set_bit(bit, buffer->scan_mask,
+				 st->num_channels) {
+			struct iio_chan_spec const *chan = idev->channels + bit;
+			at91_adc_writel(st, AT91_ADC_CHDR,
+					AT91_ADC_CH(chan->channel));
+		}
+		kfree(st->buffer);
+	}
+
+	return 0;
+}
+
+static const struct iio_trigger_ops at91_adc_trigger_ops = {
+	.owner = THIS_MODULE,
+	.set_trigger_state = &at91_adc_configure_trigger,
+};
+
+static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *idev,
+						     struct at91_adc_trigger *trigger)
+{
+	struct iio_trigger *trig;
+	int ret;
+
+	trig = iio_trigger_alloc("%s-dev%d-%s", idev->name,
+				 idev->id, trigger->name);
+	if (trig == NULL)
+		return NULL;
+
+	trig->dev.parent = idev->dev.parent;
+	trig->private_data = idev;
+	trig->ops = &at91_adc_trigger_ops;
+
+	ret = iio_trigger_register(trig);
+	if (ret)
+		return NULL;
+
+	return trig;
+}
+
+static int at91_adc_trigger_init(struct iio_dev *idev)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	int i, ret;
+
+	st->trig = devm_kzalloc(&idev->dev,
+				st->trigger_number * sizeof(st->trig),
+				GFP_KERNEL);
+
+	if (st->trig == NULL) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	for (i = 0; i < st->trigger_number; i++) {
+		if (st->trigger_list[i].is_external && !(st->use_external))
+			continue;
+
+		st->trig[i] = at91_adc_allocate_trigger(idev,
+							st->trigger_list + i);
+		if (st->trig[i] == NULL) {
+			dev_err(&idev->dev,
+				"Could not allocate trigger %d\n", i);
+			ret = -ENOMEM;
+			goto error_trigger;
+		}
+	}
+
+	return 0;
+
+error_trigger:
+	for (i--; i >= 0; i--) {
+		iio_trigger_unregister(st->trig[i]);
+		iio_trigger_free(st->trig[i]);
+	}
+error_ret:
+	return ret;
+}
+
+static void at91_adc_trigger_remove(struct iio_dev *idev)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	int i;
+
+	for (i = 0; i < st->trigger_number; i++) {
+		iio_trigger_unregister(st->trig[i]);
+		iio_trigger_free(st->trig[i]);
+	}
+}
+
+static const struct iio_buffer_setup_ops at91_adc_buffer_ops = {
+	.preenable = &iio_sw_buffer_preenable,
+	.postenable = &iio_triggered_buffer_postenable,
+	.predisable = &iio_triggered_buffer_predisable,
+};
+
+static int at91_adc_buffer_init(struct iio_dev *idev)
+{
+	int ret;
+
+	idev->buffer = iio_kfifo_allocate(idev);
+	if (!idev->buffer) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	idev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
+					    &at91_adc_trigger_handler,
+					    IRQF_ONESHOT,
+					    idev,
+					    "%s-consumer%d",
+					    idev->name,
+					    idev->id);
+	if (idev->pollfunc == NULL) {
+		ret = -ENOMEM;
+		goto error_pollfunc;
+	}
+
+	idev->setup_ops = &at91_adc_buffer_ops;
+	idev->modes |= INDIO_BUFFER_TRIGGERED;
+
+	ret = iio_buffer_register(idev,
+				  idev->channels,
+				  idev->num_channels);
+	if (ret)
+		goto error_register;
+
+	return 0;
+
+error_register:
+	iio_dealloc_pollfunc(idev->pollfunc);
+error_pollfunc:
+	iio_kfifo_free(idev->buffer);
+error_ret:
+	return ret;
+}
+
+static void at91_adc_buffer_remove(struct iio_dev *idev)
+{
+	iio_buffer_unregister(idev);
+	iio_dealloc_pollfunc(idev->pollfunc);
+	iio_kfifo_free(idev->buffer);
+}
+
+static int at91_adc_read_raw(struct iio_dev *idev,
+			     struct iio_chan_spec const *chan,
+			     int *val, int *val2, long mask)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&st->lock);
+
+		at91_adc_writel(st, AT91_ADC_CHER,
+				AT91_ADC_CH(chan->channel));
+		at91_adc_writel(st, AT91_ADC_IER, st->registers->drdy_mask);
+		at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_START);
+
+		ret = wait_event_interruptible_timeout(st->wq_data_avail,
+						       st->done,
+						       msecs_to_jiffies(1000));
+		if (ret == 0)
+			return -ETIMEDOUT;
+		else if (ret < 0)
+			return ret;
+
+		*val = st->last_value;
+
+		at91_adc_writel(st, AT91_ADC_CHDR,
+				AT91_ADC_CH(chan->channel));
+		at91_adc_writel(st, AT91_ADC_IDR, st->registers->drdy_mask);
+
+		st->last_value = 0;
+		st->done = false;
+		mutex_unlock(&st->lock);
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		*val = (st->vref_mv * 1000) >> chan->scan_type.realbits;
+		*val2 = 0;
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		break;
+	}
+	return -EINVAL;
+}
+
+static int at91_adc_probe_pdata(struct at91_adc_state *st,
+				struct platform_device *pdev)
+{
+	struct at91_adc_data *pdata = pdev->dev.platform_data;
+
+	if (!pdata)
+		return -EINVAL;
+
+	st->use_external = pdata->use_external_triggers;
+	st->vref_mv = pdata->vref;
+	st->channels_mask = pdata->channels_used;
+	st->num_channels = pdata->num_channels;
+	st->startup_time = pdata->startup_time;
+	st->trigger_number = pdata->trigger_number;
+	st->trigger_list = pdata->trigger_list;
+	st->registers = pdata->registers;
+
+	return 0;
+}
+
+static const struct iio_info at91_adc_info = {
+	.driver_module = THIS_MODULE,
+	.read_raw = &at91_adc_read_raw,
+};
+
+static int __devinit at91_adc_probe(struct platform_device *pdev)
+{
+	unsigned int prsc, mstrclk, ticks, adc_clk;
+	int ret;
+	struct iio_dev *idev;
+	struct at91_adc_state *st;
+	struct resource *res;
+
+	idev = iio_device_alloc(sizeof(struct at91_adc_state));
+	if (idev == NULL) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	st = iio_priv(idev);
+
+	ret = at91_adc_probe_pdata(st, pdev);
+	if (ret) {
+		dev_err(&pdev->dev, "No platform data available.\n");
+		ret = -EINVAL;
+		goto error_free_device;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "No resource defined\n");
+		ret = -ENXIO;
+		goto error_ret;
+	}
+
+	platform_set_drvdata(pdev, idev);
+
+	idev->dev.parent = &pdev->dev;
+	idev->name = dev_name(&pdev->dev);
+	idev->modes = INDIO_DIRECT_MODE;
+	idev->info = &at91_adc_info;
+
+	st->irq = platform_get_irq(pdev, 0);
+	if (st->irq < 0) {
+		dev_err(&pdev->dev, "No IRQ ID is designated\n");
+		ret = -ENODEV;
+		goto error_free_device;
+	}
+
+	if (!request_mem_region(res->start, resource_size(res),
+				"AT91 adc registers")) {
+		dev_err(&pdev->dev, "Resources are unavailable.\n");
+		ret = -EBUSY;
+		goto error_free_device;
+	}
+
+	st->reg_base = ioremap(res->start, resource_size(res));
+	if (!st->reg_base) {
+		dev_err(&pdev->dev, "Failed to map registers.\n");
+		ret = -ENOMEM;
+		goto error_release_mem;
+	}
+
+	/*
+	 * Disable all IRQs before setting up the handler
+	 */
+	at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST);
+	at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
+	ret = request_irq(st->irq,
+			  at91_adc_eoc_trigger,
+			  0,
+			  pdev->dev.driver->name,
+			  idev);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to allocate IRQ.\n");
+		goto error_unmap_reg;
+	}
+
+	st->clk = clk_get(&pdev->dev, "adc_clk");
+	if (IS_ERR(st->clk)) {
+		dev_err(&pdev->dev, "Failed to get the clock.\n");
+		ret = PTR_ERR(st->clk);
+		goto error_free_irq;
+	}
+
+	ret = clk_prepare(st->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not prepare the clock.\n");
+		goto error_free_clk;
+	}
+
+	ret = clk_enable(st->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not enable the clock.\n");
+		goto error_unprepare_clk;
+	}
+
+	st->adc_clk = clk_get(&pdev->dev, "adc_op_clk");
+	if (IS_ERR(st->adc_clk)) {
+		dev_err(&pdev->dev, "Failed to get the ADC clock.\n");
+		ret = PTR_ERR(st->clk);
+		goto error_disable_clk;
+	}
+
+	ret = clk_prepare(st->adc_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not prepare the ADC clock.\n");
+		goto error_free_adc_clk;
+	}
+
+	ret = clk_enable(st->adc_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not enable the ADC clock.\n");
+		goto error_unprepare_adc_clk;
+	}
+
+	/*
+	 * Prescaler rate computation using the formula from the Atmel's
+	 * datasheet : ADC Clock = MCK / ((Prescaler + 1) * 2), ADC Clock being
+	 * specified by the electrical characteristics of the board.
+	 */
+	mstrclk = clk_get_rate(st->clk);
+	adc_clk = clk_get_rate(st->adc_clk);
+	prsc = (mstrclk / (2 * adc_clk)) - 1;
+
+	if (!st->startup_time) {
+		dev_err(&pdev->dev, "No startup time available.\n");
+		ret = -EINVAL;
+		goto error_disable_adc_clk;
+	}
+
+	/*
+	 * Number of ticks needed to cover the startup time of the ADC as
+	 * defined in the electrical characteristics of the board, divided by 8.
+	 * The formula thus is : Startup Time = (ticks + 1) * 8 / ADC Clock
+	 */
+	ticks = round_up((st->startup_time * adc_clk /
+			  1000000) - 1, 8) / 8;
+	at91_adc_writel(st, AT91_ADC_MR,
+			(AT91_ADC_PRESCAL_(prsc) & AT91_ADC_PRESCAL) |
+			(AT91_ADC_STARTUP_(ticks) & AT91_ADC_STARTUP));
+
+	/* Setup the ADC channels available on the board */
+	ret = at91_adc_channel_init(idev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Couldn't initialize the channels.\n");
+		goto error_disable_adc_clk;
+	}
+
+	init_waitqueue_head(&st->wq_data_avail);
+	mutex_init(&st->lock);
+
+	ret = at91_adc_buffer_init(idev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
+		goto error_disable_adc_clk;
+	}
+
+	ret = at91_adc_trigger_init(idev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
+		goto error_unregister_buffer;
+	}
+
+	ret = iio_device_register(idev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Couldn't register the device.\n");
+		goto error_remove_triggers;
+	}
+
+	return 0;
+
+error_remove_triggers:
+	at91_adc_trigger_remove(idev);
+error_unregister_buffer:
+	at91_adc_buffer_remove(idev);
+error_disable_adc_clk:
+	clk_disable(st->adc_clk);
+error_unprepare_adc_clk:
+	clk_unprepare(st->adc_clk);
+error_free_adc_clk:
+	clk_put(st->adc_clk);
+error_disable_clk:
+	clk_disable(st->clk);
+error_unprepare_clk:
+	clk_unprepare(st->clk);
+error_free_clk:
+	clk_put(st->clk);
+error_free_irq:
+	free_irq(st->irq, idev);
+error_unmap_reg:
+	iounmap(st->reg_base);
+error_release_mem:
+	release_mem_region(res->start, resource_size(res));
+error_free_device:
+	iio_device_free(idev);
+error_ret:
+	return ret;
+}
+
+static int __devexit at91_adc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *idev = platform_get_drvdata(pdev);
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	struct at91_adc_state *st = iio_priv(idev);
+
+	iio_device_unregister(idev);
+	at91_adc_trigger_remove(idev);
+	at91_adc_buffer_remove(idev);
+	clk_disable(st->adc_clk);
+	clk_unprepare(st->adc_clk);
+	clk_put(st->adc_clk);
+	clk_disable(st->clk);
+	clk_unprepare(st->clk);
+	clk_put(st->clk);
+	free_irq(st->irq, idev);
+	iounmap(st->reg_base);
+	release_mem_region(res->start, resource_size(res));
+	iio_device_free(idev);
+
+	return 0;
+}
+
+static struct platform_driver at91_adc_driver = {
+	.probe = at91_adc_probe,
+	.remove = __devexit_p(at91_adc_remove),
+	.driver = {
+		   .name = "at91_adc",
+	},
+};
+
+module_platform_driver(at91_adc_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Atmel AT91 ADC Driver");
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
-- 
1.7.9.5

[PATCH 2/9] ARM: AT91: IIO: Add AT91 ADC driver.

[Maxime Ripard]

Add the ADC driver for Atmel's AT91SAM9G20-EK, AT91SAM9M10G45-EK
and AT91SAM9X5 family boards.

It has support for both software and hardware triggers.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 drivers/iio/Kconfig        |    2 +
 drivers/iio/Makefile       |    2 +
 drivers/iio/adc/Kconfig    |   16 ++
 drivers/iio/adc/Makefile   |    5 +
 drivers/iio/adc/at91_adc.c |  673 ++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 698 insertions(+)
 create mode 100644 drivers/iio/adc/Kconfig
 create mode 100644 drivers/iio/adc/Makefile
 create mode 100644 drivers/iio/adc/at91_adc.c

diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
index 3ab7d48..47e0920 100644
--- a/drivers/iio/Kconfig
+++ b/drivers/iio/Kconfig
@@ -48,4 +48,6 @@ config IIO_CONSUMERS_PER_TRIGGER
 	This value controls the maximum number of consumers that a
 	given trigger may handle. Default is 2.
 
+source "drivers/iio/adc/Kconfig"
+
 endif # IIO
diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
index d5fc57d..eb926a2 100644
--- a/drivers/iio/Makefile
+++ b/drivers/iio/Makefile
@@ -8,3 +8,5 @@ industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o
 industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o
 
 obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o
+
+obj-y += adc/
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
new file mode 100644
index 0000000..9a0df81
--- /dev/null
+++ b/drivers/iio/adc/Kconfig
@@ -0,0 +1,16 @@
+#
+# ADC drivers
+#
+menu "Analog to digital converters"
+
+config AT91_ADC
+	tristate "Atmel AT91 ADC"
+	depends on ARCH_AT91
+	select IIO_BUFFER
+	select IIO_KFIFO_BUF
+	select IIO_TRIGGER
+	select SYSFS
+	help
+	  Say yes here to build support for Atmel AT91 ADC.
+
+endmenu
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
new file mode 100644
index 0000000..b62d488
--- /dev/null
+++ b/drivers/iio/adc/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for IIO ADC drivers
+#
+
+obj-$(CONFIG_AT91_ADC) += at91_adc.o
\ No newline at end of file
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
new file mode 100644
index 0000000..e5d73b1
--- /dev/null
+++ b/drivers/iio/adc/at91_adc.c
@@ -0,0 +1,673 @@
+/*
+ * Driver for the ADC present in the Atmel AT91 evaluation boards.
+ *
+ * Copyright 2011 Free Electrons
+ *
+ * Licensed under the GPLv2 or later.
+ */
+
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+
+#include <linux/platform_data/at91_adc.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+
+#include <mach/at91_adc.h>
+
+#define AT91_ADC_CHAN(st, ch) \
+	(st->registers->channel_base + (ch * 4))
+#define at91_adc_readl(st, reg) \
+	(readl_relaxed(st->reg_base + reg))
+#define at91_adc_writel(st, reg, val) \
+	(writel_relaxed(val, st->reg_base + reg))
+
+struct at91_adc_state {
+	struct clk		*adc_clk;
+	u16			*buffer;
+	unsigned long		channels_mask;
+	struct clk		*clk;
+	bool			done;
+	int			irq;
+	bool			irq_enabled;
+	u16			last_value;
+	struct mutex		lock;
+	u8			num_channels;
+	void __iomem		*reg_base;
+	struct at91_adc_reg_desc *registers;
+	u8			startup_time;
+	struct iio_trigger	**trig;
+	struct at91_adc_trigger	*trigger_list;
+	u32			trigger_number;
+	bool			use_external;
+	u32			vref_mv;
+	wait_queue_head_t	wq_data_avail;
+};
+
+static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *idev = pf->indio_dev;
+	struct at91_adc_state *st = iio_priv(idev);
+	struct iio_buffer *buffer = idev->buffer;
+	int i, j = 0;
+
+	for (i = 0; i < idev->masklength; i++) {
+		if (!test_bit(i, idev->active_scan_mask))
+			continue;
+		st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, i));
+		j++;
+	}
+
+	if (idev->scan_timestamp) {
+		s64 *timestamp = (s64 *)((u8 *)st->buffer +
+					ALIGN(j, sizeof(s64)));
+		*timestamp = pf->timestamp;
+	}
+
+	buffer->access->store_to(buffer, (u8 *)st->buffer, pf->timestamp);
+
+	iio_trigger_notify_done(idev->trig);
+	st->irq_enabled = true;
+
+	/* Needed to ACK the DRDY interruption */
+	at91_adc_readl(st, AT91_ADC_LCDR);
+
+	enable_irq(st->irq);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t at91_adc_eoc_trigger(int irq, void *private)
+{
+	struct iio_dev *idev = private;
+	struct at91_adc_state *st = iio_priv(idev);
+	u32 status = at91_adc_readl(st, st->registers->status_register);
+
+	if (!(status & st->registers->drdy_mask))
+		return IRQ_HANDLED;
+
+	if (iio_buffer_enabled(idev)) {
+		disable_irq_nosync(irq);
+		st->irq_enabled = false;
+		iio_trigger_poll(idev->trig, iio_get_time_ns());
+	} else {
+		st->last_value = at91_adc_readl(st, AT91_ADC_LCDR);
+		st->done = true;
+		wake_up_interruptible(&st->wq_data_avail);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int at91_adc_channel_init(struct iio_dev *idev)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	struct iio_chan_spec *chan_array, *timestamp;
+	int bit, idx = 0;
+
+	idev->num_channels = bitmap_weight(&st->channels_mask,
+					   st->num_channels) + 1;
+
+	chan_array = devm_kzalloc(&idev->dev,
+				  ((idev->num_channels + 1) *
+					sizeof(struct iio_chan_spec)),
+				  GFP_KERNEL);
+
+	if (!chan_array)
+		return -ENOMEM;
+
+	for_each_set_bit(bit, &st->channels_mask, st->num_channels) {
+		struct iio_chan_spec *chan = chan_array + idx;
+
+		chan->type = IIO_VOLTAGE;
+		chan->indexed = 1;
+		chan->channel = bit;
+		chan->scan_index = idx;
+		chan->scan_type.sign = 'u';
+		chan->scan_type.realbits = 10;
+		chan->scan_type.storagebits = 16;
+		chan->info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT |
+			IIO_CHAN_INFO_RAW_SEPARATE_BIT;
+		idx++;
+	}
+	timestamp = chan_array + idx;
+
+	timestamp->type = IIO_TIMESTAMP;
+	timestamp->channel = -1;
+	timestamp->scan_index = idx;
+	timestamp->scan_type.sign = 's';
+	timestamp->scan_type.realbits = 64;
+	timestamp->scan_type.storagebits = 64;
+
+	idev->channels = chan_array;
+	return idev->num_channels;
+}
+
+static u8 at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
+					     struct at91_adc_trigger *triggers,
+					     const char *trigger_name)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	u8 value = 0;
+	int i;
+
+	for (i = 0; i < st->trigger_number; i++) {
+		char *name = kasprintf(GFP_KERNEL,
+				"%s-dev%d-%s",
+				idev->name,
+				idev->id,
+				triggers[i].name);
+		if (!name)
+			return -ENOMEM;
+
+		if (strcmp(trigger_name, name) == 0) {
+			value = triggers[i].value;
+			kfree(name);
+			break;
+		}
+
+		kfree(name);
+	}
+
+	return value;
+}
+
+static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
+{
+	struct iio_dev *idev = trig->private_data;
+	struct at91_adc_state *st = iio_priv(idev);
+	struct iio_buffer *buffer = idev->buffer;
+	struct at91_adc_reg_desc *reg = st->registers;
+	u32 status = at91_adc_readl(st, reg->trigger_register);
+	u8 value;
+	u8 bit;
+
+	value = at91_adc_get_trigger_value_by_name(idev,
+						   st->trigger_list,
+						   idev->trig->name);
+	if (value == 0)
+		return -EINVAL;
+
+	if (state) {
+		st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL);
+		if (st->buffer == NULL)
+			return -ENOMEM;
+
+		at91_adc_writel(st, reg->trigger_register,
+				status | value);
+
+		for_each_set_bit(bit, buffer->scan_mask,
+				 st->num_channels) {
+			struct iio_chan_spec const *chan = idev->channels + bit;
+			at91_adc_writel(st, AT91_ADC_CHER,
+					AT91_ADC_CH(chan->channel));
+		}
+
+		at91_adc_writel(st, AT91_ADC_IER, reg->drdy_mask);
+
+	} else {
+		at91_adc_writel(st, AT91_ADC_IDR, reg->drdy_mask);
+
+		at91_adc_writel(st, reg->trigger_register,
+				status & ~value);
+
+		for_each_set_bit(bit, buffer->scan_mask,
+				 st->num_channels) {
+			struct iio_chan_spec const *chan = idev->channels + bit;
+			at91_adc_writel(st, AT91_ADC_CHDR,
+					AT91_ADC_CH(chan->channel));
+		}
+		kfree(st->buffer);
+	}
+
+	return 0;
+}
+
+static const struct iio_trigger_ops at91_adc_trigger_ops = {
+	.owner = THIS_MODULE,
+	.set_trigger_state = &at91_adc_configure_trigger,
+};
+
+static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *idev,
+						     struct at91_adc_trigger *trigger)
+{
+	struct iio_trigger *trig;
+	int ret;
+
+	trig = iio_trigger_alloc("%s-dev%d-%s", idev->name,
+				 idev->id, trigger->name);
+	if (trig == NULL)
+		return NULL;
+
+	trig->dev.parent = idev->dev.parent;
+	trig->private_data = idev;
+	trig->ops = &at91_adc_trigger_ops;
+
+	ret = iio_trigger_register(trig);
+	if (ret)
+		return NULL;
+
+	return trig;
+}
+
+static int at91_adc_trigger_init(struct iio_dev *idev)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	int i, ret;
+
+	st->trig = devm_kzalloc(&idev->dev,
+				st->trigger_number * sizeof(st->trig),
+				GFP_KERNEL);
+
+	if (st->trig == NULL) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	for (i = 0; i < st->trigger_number; i++) {
+		if (st->trigger_list[i].is_external && !(st->use_external))
+			continue;
+
+		st->trig[i] = at91_adc_allocate_trigger(idev,
+							st->trigger_list + i);
+		if (st->trig[i] == NULL) {
+			dev_err(&idev->dev,
+				"Could not allocate trigger %d\n", i);
+			ret = -ENOMEM;
+			goto error_trigger;
+		}
+	}
+
+	return 0;
+
+error_trigger:
+	for (i--; i >= 0; i--) {
+		iio_trigger_unregister(st->trig[i]);
+		iio_trigger_free(st->trig[i]);
+	}
+error_ret:
+	return ret;
+}
+
+static void at91_adc_trigger_remove(struct iio_dev *idev)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	int i;
+
+	for (i = 0; i < st->trigger_number; i++) {
+		iio_trigger_unregister(st->trig[i]);
+		iio_trigger_free(st->trig[i]);
+	}
+}
+
+static const struct iio_buffer_setup_ops at91_adc_buffer_ops = {
+	.preenable = &iio_sw_buffer_preenable,
+	.postenable = &iio_triggered_buffer_postenable,
+	.predisable = &iio_triggered_buffer_predisable,
+};
+
+static int at91_adc_buffer_init(struct iio_dev *idev)
+{
+	int ret;
+
+	idev->buffer = iio_kfifo_allocate(idev);
+	if (!idev->buffer) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	idev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
+					    &at91_adc_trigger_handler,
+					    IRQF_ONESHOT,
+					    idev,
+					    "%s-consumer%d",
+					    idev->name,
+					    idev->id);
+	if (idev->pollfunc == NULL) {
+		ret = -ENOMEM;
+		goto error_pollfunc;
+	}
+
+	idev->setup_ops = &at91_adc_buffer_ops;
+	idev->modes |= INDIO_BUFFER_TRIGGERED;
+
+	ret = iio_buffer_register(idev,
+				  idev->channels,
+				  idev->num_channels);
+	if (ret)
+		goto error_register;
+
+	return 0;
+
+error_register:
+	iio_dealloc_pollfunc(idev->pollfunc);
+error_pollfunc:
+	iio_kfifo_free(idev->buffer);
+error_ret:
+	return ret;
+}
+
+static void at91_adc_buffer_remove(struct iio_dev *idev)
+{
+	iio_buffer_unregister(idev);
+	iio_dealloc_pollfunc(idev->pollfunc);
+	iio_kfifo_free(idev->buffer);
+}
+
+static int at91_adc_read_raw(struct iio_dev *idev,
+			     struct iio_chan_spec const *chan,
+			     int *val, int *val2, long mask)
+{
+	struct at91_adc_state *st = iio_priv(idev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&st->lock);
+
+		at91_adc_writel(st, AT91_ADC_CHER,
+				AT91_ADC_CH(chan->channel));
+		at91_adc_writel(st, AT91_ADC_IER, st->registers->drdy_mask);
+		at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_START);
+
+		ret = wait_event_interruptible_timeout(st->wq_data_avail,
+						       st->done,
+						       msecs_to_jiffies(1000));
+		if (ret == 0)
+			return -ETIMEDOUT;
+		else if (ret < 0)
+			return ret;
+
+		*val = st->last_value;
+
+		at91_adc_writel(st, AT91_ADC_CHDR,
+				AT91_ADC_CH(chan->channel));
+		at91_adc_writel(st, AT91_ADC_IDR, st->registers->drdy_mask);
+
+		st->last_value = 0;
+		st->done = false;
+		mutex_unlock(&st->lock);
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		*val = (st->vref_mv * 1000) >> chan->scan_type.realbits;
+		*val2 = 0;
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		break;
+	}
+	return -EINVAL;
+}
+
+static int at91_adc_probe_pdata(struct at91_adc_state *st,
+				struct platform_device *pdev)
+{
+	struct at91_adc_data *pdata = pdev->dev.platform_data;
+
+	if (!pdata)
+		return -EINVAL;
+
+	st->use_external = pdata->use_external_triggers;
+	st->vref_mv = pdata->vref;
+	st->channels_mask = pdata->channels_used;
+	st->num_channels = pdata->num_channels;
+	st->startup_time = pdata->startup_time;
+	st->trigger_number = pdata->trigger_number;
+	st->trigger_list = pdata->trigger_list;
+	st->registers = pdata->registers;
+
+	return 0;
+}
+
+static const struct iio_info at91_adc_info = {
+	.driver_module = THIS_MODULE,
+	.read_raw = &at91_adc_read_raw,
+};
+
+static int __devinit at91_adc_probe(struct platform_device *pdev)
+{
+	unsigned int prsc, mstrclk, ticks, adc_clk;
+	int ret;
+	struct iio_dev *idev;
+	struct at91_adc_state *st;
+	struct resource *res;
+
+	idev = iio_device_alloc(sizeof(struct at91_adc_state));
+	if (idev == NULL) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	st = iio_priv(idev);
+
+	ret = at91_adc_probe_pdata(st, pdev);
+	if (ret) {
+		dev_err(&pdev->dev, "No platform data available.\n");
+		ret = -EINVAL;
+		goto error_free_device;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "No resource defined\n");
+		ret = -ENXIO;
+		goto error_ret;
+	}
+
+	platform_set_drvdata(pdev, idev);
+
+	idev->dev.parent = &pdev->dev;
+	idev->name = dev_name(&pdev->dev);
+	idev->modes = INDIO_DIRECT_MODE;
+	idev->info = &at91_adc_info;
+
+	st->irq = platform_get_irq(pdev, 0);
+	if (st->irq < 0) {
+		dev_err(&pdev->dev, "No IRQ ID is designated\n");
+		ret = -ENODEV;
+		goto error_free_device;
+	}
+
+	if (!request_mem_region(res->start, resource_size(res),
+				"AT91 adc registers")) {
+		dev_err(&pdev->dev, "Resources are unavailable.\n");
+		ret = -EBUSY;
+		goto error_free_device;
+	}
+
+	st->reg_base = ioremap(res->start, resource_size(res));
+	if (!st->reg_base) {
+		dev_err(&pdev->dev, "Failed to map registers.\n");
+		ret = -ENOMEM;
+		goto error_release_mem;
+	}
+
+	/*
+	 * Disable all IRQs before setting up the handler
+	 */
+	at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST);
+	at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
+	ret = request_irq(st->irq,
+			  at91_adc_eoc_trigger,
+			  0,
+			  pdev->dev.driver->name,
+			  idev);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to allocate IRQ.\n");
+		goto error_unmap_reg;
+	}
+
+	st->clk = clk_get(&pdev->dev, "adc_clk");
+	if (IS_ERR(st->clk)) {
+		dev_err(&pdev->dev, "Failed to get the clock.\n");
+		ret = PTR_ERR(st->clk);
+		goto error_free_irq;
+	}
+
+	ret = clk_prepare(st->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not prepare the clock.\n");
+		goto error_free_clk;
+	}
+
+	ret = clk_enable(st->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not enable the clock.\n");
+		goto error_unprepare_clk;
+	}
+
+	st->adc_clk = clk_get(&pdev->dev, "adc_op_clk");
+	if (IS_ERR(st->adc_clk)) {
+		dev_err(&pdev->dev, "Failed to get the ADC clock.\n");
+		ret = PTR_ERR(st->clk);
+		goto error_disable_clk;
+	}
+
+	ret = clk_prepare(st->adc_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not prepare the ADC clock.\n");
+		goto error_free_adc_clk;
+	}
+
+	ret = clk_enable(st->adc_clk);
+	if (ret) {
+		dev_err(&pdev->dev, "Could not enable the ADC clock.\n");
+		goto error_unprepare_adc_clk;
+	}
+
+	/*
+	 * Prescaler rate computation using the formula from the Atmel's
+	 * datasheet : ADC Clock = MCK / ((Prescaler + 1) * 2), ADC Clock being
+	 * specified by the electrical characteristics of the board.
+	 */
+	mstrclk = clk_get_rate(st->clk);
+	adc_clk = clk_get_rate(st->adc_clk);
+	prsc = (mstrclk / (2 * adc_clk)) - 1;
+
+	if (!st->startup_time) {
+		dev_err(&pdev->dev, "No startup time available.\n");
+		ret = -EINVAL;
+		goto error_disable_adc_clk;
+	}
+
+	/*
+	 * Number of ticks needed to cover the startup time of the ADC as
+	 * defined in the electrical characteristics of the board, divided by 8.
+	 * The formula thus is : Startup Time = (ticks + 1) * 8 / ADC Clock
+	 */
+	ticks = round_up((st->startup_time * adc_clk /
+			  1000000) - 1, 8) / 8;
+	at91_adc_writel(st, AT91_ADC_MR,
+			(AT91_ADC_PRESCAL_(prsc) & AT91_ADC_PRESCAL) |
+			(AT91_ADC_STARTUP_(ticks) & AT91_ADC_STARTUP));
+
+	/* Setup the ADC channels available on the board */
+	ret = at91_adc_channel_init(idev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Couldn't initialize the channels.\n");
+		goto error_disable_adc_clk;
+	}
+
+	init_waitqueue_head(&st->wq_data_avail);
+	mutex_init(&st->lock);
+
+	ret = at91_adc_buffer_init(idev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
+		goto error_disable_adc_clk;
+	}
+
+	ret = at91_adc_trigger_init(idev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
+		goto error_unregister_buffer;
+	}
+
+	ret = iio_device_register(idev);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Couldn't register the device.\n");
+		goto error_remove_triggers;
+	}
+
+	return 0;
+
+error_remove_triggers:
+	at91_adc_trigger_remove(idev);
+error_unregister_buffer:
+	at91_adc_buffer_remove(idev);
+error_disable_adc_clk:
+	clk_disable(st->adc_clk);
+error_unprepare_adc_clk:
+	clk_unprepare(st->adc_clk);
+error_free_adc_clk:
+	clk_put(st->adc_clk);
+error_disable_clk:
+	clk_disable(st->clk);
+error_unprepare_clk:
+	clk_unprepare(st->clk);
+error_free_clk:
+	clk_put(st->clk);
+error_free_irq:
+	free_irq(st->irq, idev);
+error_unmap_reg:
+	iounmap(st->reg_base);
+error_release_mem:
+	release_mem_region(res->start, resource_size(res));
+error_free_device:
+	iio_device_free(idev);
+error_ret:
+	return ret;
+}
+
+static int __devexit at91_adc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *idev = platform_get_drvdata(pdev);
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	struct at91_adc_state *st = iio_priv(idev);
+
+	iio_device_unregister(idev);
+	at91_adc_trigger_remove(idev);
+	at91_adc_buffer_remove(idev);
+	clk_disable(st->adc_clk);
+	clk_unprepare(st->adc_clk);
+	clk_put(st->adc_clk);
+	clk_disable(st->clk);
+	clk_unprepare(st->clk);
+	clk_put(st->clk);
+	free_irq(st->irq, idev);
+	iounmap(st->reg_base);
+	release_mem_region(res->start, resource_size(res));
+	iio_device_free(idev);
+
+	return 0;
+}
+
+static struct platform_driver at91_adc_driver = {
+	.probe = at91_adc_probe,
+	.remove = __devexit_p(at91_adc_remove),
+	.driver = {
+		   .name = "at91_adc",
+	},
+};
+
+module_platform_driver(at91_adc_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Atmel AT91 ADC Driver");
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
-- 
1.7.9.5

Re: [PATCH 2/9] ARM: AT91: IIO: Add AT91 ADC driver.

[Jonathan Cameron]

On 5/9/2012 2:02 PM, Maxime Ripard wrote:
> Add the ADC driver for Atmel's AT91SAM9G20-EK, AT91SAM9M10G45-EK
> and AT91SAM9X5 family boards.
>
> It has support for both software and hardware triggers.
Totally trivial, but please add a newline where it says below. 
Otherwise, looks
fine to me.  Couple of other passing comments inline, but nothing else 
to change
unless you particularly want to.
> Signed-off-by: Maxime Ripard<maxime.ripard@free-electrons.com>
> Acked-by: Nicolas Ferre<nicolas.ferre@atmel.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
>   drivers/iio/Kconfig        |    2 +
>   drivers/iio/Makefile       |    2 +
>   drivers/iio/adc/Kconfig    |   16 ++
>   drivers/iio/adc/Makefile   |    5 +
>   drivers/iio/adc/at91_adc.c |  673 ++++++++++++++++++++++++++++++++++++++++++++
>   5 files changed, 698 insertions(+)
>   create mode 100644 drivers/iio/adc/Kconfig
>   create mode 100644 drivers/iio/adc/Makefile
>   create mode 100644 drivers/iio/adc/at91_adc.c
>
> diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
> index 3ab7d48..47e0920 100644
> --- a/drivers/iio/Kconfig
> +++ b/drivers/iio/Kconfig
> @@ -48,4 +48,6 @@ config IIO_CONSUMERS_PER_TRIGGER
>   	This value controls the maximum number of consumers that a
>   	given trigger may handle. Default is 2.
>
> +source "drivers/iio/adc/Kconfig"
> +
>   endif # IIO
> diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
> index d5fc57d..eb926a2 100644
> --- a/drivers/iio/Makefile
> +++ b/drivers/iio/Makefile
> @@ -8,3 +8,5 @@ industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o
>   industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o
>
>   obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o
> +
> +obj-y += adc/
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> new file mode 100644
> index 0000000..9a0df81
> --- /dev/null
> +++ b/drivers/iio/adc/Kconfig
> @@ -0,0 +1,16 @@
> +#
> +# ADC drivers
> +#
> +menu "Analog to digital converters"
> +
> +config AT91_ADC
> +	tristate "Atmel AT91 ADC"
> +	depends on ARCH_AT91
> +	select IIO_BUFFER
> +	select IIO_KFIFO_BUF
> +	select IIO_TRIGGER
> +	select SYSFS
> +	help
> +	  Say yes here to build support for Atmel AT91 ADC.
> +
> +endmenu
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> new file mode 100644
> index 0000000..b62d488
> --- /dev/null
> +++ b/drivers/iio/adc/Makefile
> @@ -0,0 +1,5 @@
> +#
> +# Makefile for IIO ADC drivers
> +#
> +
> +obj-$(CONFIG_AT91_ADC) += at91_adc.o
Please add a newline here.
> \ No newline at end of file
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> new file mode 100644
> index 0000000..e5d73b1
> --- /dev/null
> +++ b/drivers/iio/adc/at91_adc.c
> @@ -0,0 +1,673 @@
> +/*
> + * Driver for the ADC present in the Atmel AT91 evaluation boards.
> + *
> + * Copyright 2011 Free Electrons
> + *
> + * Licensed under the GPLv2 or later.
> + */
> +
> +#include<linux/bitmap.h>
> +#include<linux/bitops.h>
> +#include<linux/clk.h>
> +#include<linux/err.h>
> +#include<linux/io.h>
> +#include<linux/interrupt.h>
> +#include<linux/jiffies.h>
> +#include<linux/kernel.h>
> +#include<linux/module.h>
> +#include<linux/platform_device.h>
> +#include<linux/sched.h>
> +#include<linux/slab.h>
> +#include<linux/wait.h>
> +
> +#include<linux/platform_data/at91_adc.h>
> +
> +#include<linux/iio/iio.h>
> +#include<linux/iio/buffer.h>
> +#include<linux/iio/kfifo_buf.h>
> +#include<linux/iio/trigger.h>
> +#include<linux/iio/trigger_consumer.h>
> +
> +#include<mach/at91_adc.h>
> +
> +#define AT91_ADC_CHAN(st, ch) \
> +	(st->registers->channel_base + (ch * 4))
> +#define at91_adc_readl(st, reg) \
> +	(readl_relaxed(st->reg_base + reg))
> +#define at91_adc_writel(st, reg, val) \
> +	(writel_relaxed(val, st->reg_base + reg))
> +
> +struct at91_adc_state {
> +	struct clk		*adc_clk;
> +	u16			*buffer;
> +	unsigned long		channels_mask;
> +	struct clk		*clk;
> +	bool			done;
> +	int			irq;
> +	bool			irq_enabled;
> +	u16			last_value;
> +	struct mutex		lock;
> +	u8			num_channels;
> +	void __iomem		*reg_base;
> +	struct at91_adc_reg_desc *registers;
> +	u8			startup_time;
> +	struct iio_trigger	**trig;
> +	struct at91_adc_trigger	*trigger_list;
> +	u32			trigger_number;
> +	bool			use_external;
> +	u32			vref_mv;
> +	wait_queue_head_t	wq_data_avail;
> +};
> +
> +static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
> +{
> +	struct iio_poll_func *pf = p;
> +	struct iio_dev *idev = pf->indio_dev;
> +	struct at91_adc_state *st = iio_priv(idev);
> +	struct iio_buffer *buffer = idev->buffer;
> +	int i, j = 0;
> +
> +	for (i = 0; i<  idev->masklength; i++) {
> +		if (!test_bit(i, idev->active_scan_mask))
> +			continue;
> +		st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, i));
> +		j++;
> +	}
> +
> +	if (idev->scan_timestamp) {
> +		s64 *timestamp = (s64 *)((u8 *)st->buffer +
> +					ALIGN(j, sizeof(s64)));
> +		*timestamp = pf->timestamp;
> +	}
> +
> +	buffer->access->store_to(buffer, (u8 *)st->buffer, pf->timestamp);
> +
> +	iio_trigger_notify_done(idev->trig);
> +	st->irq_enabled = true;
> +
> +	/* Needed to ACK the DRDY interruption */
> +	at91_adc_readl(st, AT91_ADC_LCDR);
> +
> +	enable_irq(st->irq);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t at91_adc_eoc_trigger(int irq, void *private)
> +{
> +	struct iio_dev *idev = private;
> +	struct at91_adc_state *st = iio_priv(idev);
> +	u32 status = at91_adc_readl(st, st->registers->status_register);
> +
> +	if (!(status&  st->registers->drdy_mask))
> +		return IRQ_HANDLED;
> +
> +	if (iio_buffer_enabled(idev)) {
> +		disable_irq_nosync(irq);
> +		st->irq_enabled = false;
> +		iio_trigger_poll(idev->trig, iio_get_time_ns());
> +	} else {
> +		st->last_value = at91_adc_readl(st, AT91_ADC_LCDR);
> +		st->done = true;
> +		wake_up_interruptible(&st->wq_data_avail);
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int at91_adc_channel_init(struct iio_dev *idev)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	struct iio_chan_spec *chan_array, *timestamp;
> +	int bit, idx = 0;
> +
> +	idev->num_channels = bitmap_weight(&st->channels_mask,
> +					   st->num_channels) + 1;
> +
> +	chan_array = devm_kzalloc(&idev->dev,
> +				  ((idev->num_channels + 1) *
> +					sizeof(struct iio_chan_spec)),
> +				  GFP_KERNEL);
> +
> +	if (!chan_array)
> +		return -ENOMEM;
> +
> +	for_each_set_bit(bit,&st->channels_mask, st->num_channels) {
> +		struct iio_chan_spec *chan = chan_array + idx;
> +
> +		chan->type = IIO_VOLTAGE;
> +		chan->indexed = 1;
> +		chan->channel = bit;
> +		chan->scan_index = idx;
> +		chan->scan_type.sign = 'u';
> +		chan->scan_type.realbits = 10;
> +		chan->scan_type.storagebits = 16;
> +		chan->info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT |
> +			IIO_CHAN_INFO_RAW_SEPARATE_BIT;
> +		idx++;
> +	}
> +	timestamp = chan_array + idx;
> +
> +	timestamp->type = IIO_TIMESTAMP;
> +	timestamp->channel = -1;
> +	timestamp->scan_index = idx;
> +	timestamp->scan_type.sign = 's';
> +	timestamp->scan_type.realbits = 64;
> +	timestamp->scan_type.storagebits = 64;
> +
> +	idev->channels = chan_array;
> +	return idev->num_channels;
> +}
> +
> +static u8 at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
> +					     struct at91_adc_trigger *triggers,
> +					     const char *trigger_name)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	u8 value = 0;
> +	int i;
> +
> +	for (i = 0; i<  st->trigger_number; i++) {
> +		char *name = kasprintf(GFP_KERNEL,
> +				"%s-dev%d-%s",
> +				idev->name,
> +				idev->id,
> +				triggers[i].name);
> +		if (!name)
> +			return -ENOMEM;
> +
> +		if (strcmp(trigger_name, name) == 0) {
> +			value = triggers[i].value;
> +			kfree(name);
> +			break;
> +		}
> +
> +		kfree(name);
> +	}
> +
> +	return value;
> +}
> +
> +static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
> +{
> +	struct iio_dev *idev = trig->private_data;
> +	struct at91_adc_state *st = iio_priv(idev);
> +	struct iio_buffer *buffer = idev->buffer;
> +	struct at91_adc_reg_desc *reg = st->registers;
> +	u32 status = at91_adc_readl(st, reg->trigger_register);
> +	u8 value;
> +	u8 bit;
> +
> +	value = at91_adc_get_trigger_value_by_name(idev,
> +						   st->trigger_list,
> +						   idev->trig->name);
> +	if (value == 0)
> +		return -EINVAL;
> +
> +	if (state) {
> +		st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL);
> +		if (st->buffer == NULL)
> +			return -ENOMEM;
> +
> +		at91_adc_writel(st, reg->trigger_register,
> +				status | value);
> +
> +		for_each_set_bit(bit, buffer->scan_mask,
> +				 st->num_channels) {
> +			struct iio_chan_spec const *chan = idev->channels + bit;
> +			at91_adc_writel(st, AT91_ADC_CHER,
> +					AT91_ADC_CH(chan->channel));
> +		}
> +
> +		at91_adc_writel(st, AT91_ADC_IER, reg->drdy_mask);
> +
> +	} else {
> +		at91_adc_writel(st, AT91_ADC_IDR, reg->drdy_mask);
> +
> +		at91_adc_writel(st, reg->trigger_register,
> +				status&  ~value);
> +
> +		for_each_set_bit(bit, buffer->scan_mask,
> +				 st->num_channels) {
> +			struct iio_chan_spec const *chan = idev->channels + bit;
> +			at91_adc_writel(st, AT91_ADC_CHDR,
> +					AT91_ADC_CH(chan->channel));
> +		}
> +		kfree(st->buffer);
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct iio_trigger_ops at91_adc_trigger_ops = {
> +	.owner = THIS_MODULE,
> +	.set_trigger_state =&at91_adc_configure_trigger,
> +};
> +
> +static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *idev,
> +						     struct at91_adc_trigger *trigger)
> +{
> +	struct iio_trigger *trig;
> +	int ret;
> +
> +	trig = iio_trigger_alloc("%s-dev%d-%s", idev->name,
> +				 idev->id, trigger->name);
> +	if (trig == NULL)
> +		return NULL;
> +
> +	trig->dev.parent = idev->dev.parent;
> +	trig->private_data = idev;
> +	trig->ops =&at91_adc_trigger_ops;
> +
> +	ret = iio_trigger_register(trig);
> +	if (ret)
> +		return NULL;
> +
> +	return trig;
> +}
> +
> +static int at91_adc_trigger_init(struct iio_dev *idev)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	int i, ret;
> +
> +	st->trig = devm_kzalloc(&idev->dev,
> +				st->trigger_number * sizeof(st->trig),
> +				GFP_KERNEL);
> +
> +	if (st->trig == NULL) {
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	for (i = 0; i<  st->trigger_number; i++) {
> +		if (st->trigger_list[i].is_external&&  !(st->use_external))
> +			continue;
> +
> +		st->trig[i] = at91_adc_allocate_trigger(idev,
> +							st->trigger_list + i);
> +		if (st->trig[i] == NULL) {
> +			dev_err(&idev->dev,
> +				"Could not allocate trigger %d\n", i);
> +			ret = -ENOMEM;
> +			goto error_trigger;
> +		}
> +	}
> +
> +	return 0;
> +
> +error_trigger:
> +	for (i--; i>= 0; i--) {
> +		iio_trigger_unregister(st->trig[i]);
> +		iio_trigger_free(st->trig[i]);
> +	}
> +error_ret:
> +	return ret;
> +}
> +
> +static void at91_adc_trigger_remove(struct iio_dev *idev)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	int i;
> +
> +	for (i = 0; i<  st->trigger_number; i++) {
> +		iio_trigger_unregister(st->trig[i]);
> +		iio_trigger_free(st->trig[i]);
> +	}
> +}
> +
> +static const struct iio_buffer_setup_ops at91_adc_buffer_ops = {
> +	.preenable =&iio_sw_buffer_preenable,
> +	.postenable =&iio_triggered_buffer_postenable,
> +	.predisable =&iio_triggered_buffer_predisable,
> +};
> +
> +static int at91_adc_buffer_init(struct iio_dev *idev)
> +{
> +	int ret;
> +
> +	idev->buffer = iio_kfifo_allocate(idev);
> +	if (!idev->buffer) {
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	idev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
> +					&at91_adc_trigger_handler,
> +					    IRQF_ONESHOT,
> +					    idev,
> +					    "%s-consumer%d",
> +					    idev->name,
> +					    idev->id);
> +	if (idev->pollfunc == NULL) {
> +		ret = -ENOMEM;
> +		goto error_pollfunc;
> +	}
> +
> +	idev->setup_ops =&at91_adc_buffer_ops;
> +	idev->modes |= INDIO_BUFFER_TRIGGERED;
> +
> +	ret = iio_buffer_register(idev,
> +				  idev->channels,
> +				  idev->num_channels);
> +	if (ret)
> +		goto error_register;
> +
> +	return 0;
> +
> +error_register:
> +	iio_dealloc_pollfunc(idev->pollfunc);
> +error_pollfunc:
> +	iio_kfifo_free(idev->buffer);
> +error_ret:
> +	return ret;
> +}
> +
> +static void at91_adc_buffer_remove(struct iio_dev *idev)
> +{
> +	iio_buffer_unregister(idev);
> +	iio_dealloc_pollfunc(idev->pollfunc);
> +	iio_kfifo_free(idev->buffer);
> +}
> +
> +static int at91_adc_read_raw(struct iio_dev *idev,
> +			     struct iio_chan_spec const *chan,
> +			     int *val, int *val2, long mask)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	int ret;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		mutex_lock(&st->lock);
> +
> +		at91_adc_writel(st, AT91_ADC_CHER,
> +				AT91_ADC_CH(chan->channel));
> +		at91_adc_writel(st, AT91_ADC_IER, st->registers->drdy_mask);
> +		at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_START);
> +
> +		ret = wait_event_interruptible_timeout(st->wq_data_avail,
> +						       st->done,
> +						       msecs_to_jiffies(1000));
> +		if (ret == 0)
> +			return -ETIMEDOUT;
> +		else if (ret<  0)
> +			return ret;
> +
> +		*val = st->last_value;
> +
> +		at91_adc_writel(st, AT91_ADC_CHDR,
> +				AT91_ADC_CH(chan->channel));
> +		at91_adc_writel(st, AT91_ADC_IDR, st->registers->drdy_mask);
> +
> +		st->last_value = 0;
> +		st->done = false;
> +		mutex_unlock(&st->lock);
> +		return IIO_VAL_INT;
> +
> +	case IIO_CHAN_INFO_SCALE:
> +		*val = (st->vref_mv * 1000)>>  chan->scan_type.realbits;
> +		*val2 = 0;
> +		return IIO_VAL_INT_PLUS_MICRO;
> +	default:
> +		break;
> +	}
> +	return -EINVAL;
> +}
> +
> +static int at91_adc_probe_pdata(struct at91_adc_state *st,
> +				struct platform_device *pdev)
> +{
> +	struct at91_adc_data *pdata = pdev->dev.platform_data;
> +
> +	if (!pdata)
> +		return -EINVAL;
> +
This does look rather like it would be better to just keep a copy of 
pdata around...
Still, not critical at all.
> +	st->use_external = pdata->use_external_triggers;
> +	st->vref_mv = pdata->vref;
> +	st->channels_mask = pdata->channels_used;
> +	st->num_channels = pdata->num_channels;
> +	st->startup_time = pdata->startup_time;
> +	st->trigger_number = pdata->trigger_number;
> +	st->trigger_list = pdata->trigger_list;
> +	st->registers = pdata->registers;
> +
> +	return 0;
> +}
> +
> +static const struct iio_info at91_adc_info = {
> +	.driver_module = THIS_MODULE,
> +	.read_raw =&at91_adc_read_raw,
> +};
> +
> +static int __devinit at91_adc_probe(struct platform_device *pdev)
> +{
> +	unsigned int prsc, mstrclk, ticks, adc_clk;
> +	int ret;
> +	struct iio_dev *idev;
> +	struct at91_adc_state *st;
> +	struct resource *res;
> +
> +	idev = iio_device_alloc(sizeof(struct at91_adc_state));
> +	if (idev == NULL) {
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	st = iio_priv(idev);
> +
> +	ret = at91_adc_probe_pdata(st, pdev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "No platform data available.\n");
> +		ret = -EINVAL;
> +		goto error_free_device;
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev, "No resource defined\n");
> +		ret = -ENXIO;
> +		goto error_ret;
> +	}
> +
> +	platform_set_drvdata(pdev, idev);
> +
> +	idev->dev.parent =&pdev->dev;
> +	idev->name = dev_name(&pdev->dev);
> +	idev->modes = INDIO_DIRECT_MODE;
> +	idev->info =&at91_adc_info;
> +
> +	st->irq = platform_get_irq(pdev, 0);
> +	if (st->irq<  0) {
> +		dev_err(&pdev->dev, "No IRQ ID is designated\n");
> +		ret = -ENODEV;
> +		goto error_free_device;
> +	}
> +
> +	if (!request_mem_region(res->start, resource_size(res),
> +				"AT91 adc registers")) {
> +		dev_err(&pdev->dev, "Resources are unavailable.\n");
> +		ret = -EBUSY;
> +		goto error_free_device;
> +	}
> +
> +	st->reg_base = ioremap(res->start, resource_size(res));
> +	if (!st->reg_base) {
> +		dev_err(&pdev->dev, "Failed to map registers.\n");
> +		ret = -ENOMEM;
> +		goto error_release_mem;
> +	}
> +
> +	/*
> +	 * Disable all IRQs before setting up the handler
> +	 */
> +	at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST);
> +	at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
> +	ret = request_irq(st->irq,
> +			  at91_adc_eoc_trigger,
> +			  0,
> +			  pdev->dev.driver->name,
> +			  idev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to allocate IRQ.\n");
> +		goto error_unmap_reg;
> +	}
> +
> +	st->clk = clk_get(&pdev->dev, "adc_clk");
> +	if (IS_ERR(st->clk)) {
> +		dev_err(&pdev->dev, "Failed to get the clock.\n");
> +		ret = PTR_ERR(st->clk);
> +		goto error_free_irq;
> +	}
> +
> +	ret = clk_prepare(st->clk);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Could not prepare the clock.\n");
> +		goto error_free_clk;
> +	}
> +
> +	ret = clk_enable(st->clk);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Could not enable the clock.\n");
> +		goto error_unprepare_clk;
> +	}
> +
> +	st->adc_clk = clk_get(&pdev->dev, "adc_op_clk");
> +	if (IS_ERR(st->adc_clk)) {
> +		dev_err(&pdev->dev, "Failed to get the ADC clock.\n");
> +		ret = PTR_ERR(st->clk);
> +		goto error_disable_clk;
> +	}
> +
> +	ret = clk_prepare(st->adc_clk);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Could not prepare the ADC clock.\n");
> +		goto error_free_adc_clk;
> +	}
> +
> +	ret = clk_enable(st->adc_clk);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Could not enable the ADC clock.\n");
> +		goto error_unprepare_adc_clk;
> +	}
> +
> +	/*
> +	 * Prescaler rate computation using the formula from the Atmel's
> +	 * datasheet : ADC Clock = MCK / ((Prescaler + 1) * 2), ADC Clock being
> +	 * specified by the electrical characteristics of the board.
> +	 */
> +	mstrclk = clk_get_rate(st->clk);
> +	adc_clk = clk_get_rate(st->adc_clk);
> +	prsc = (mstrclk / (2 * adc_clk)) - 1;
> +
> +	if (!st->startup_time) {
> +		dev_err(&pdev->dev, "No startup time available.\n");
> +		ret = -EINVAL;
> +		goto error_disable_adc_clk;
> +	}
> +
> +	/*
> +	 * Number of ticks needed to cover the startup time of the ADC as
> +	 * defined in the electrical characteristics of the board, divided by 8.
> +	 * The formula thus is : Startup Time = (ticks + 1) * 8 / ADC Clock
> +	 */
> +	ticks = round_up((st->startup_time * adc_clk /
> +			  1000000) - 1, 8) / 8;
> +	at91_adc_writel(st, AT91_ADC_MR,
> +			(AT91_ADC_PRESCAL_(prsc)&  AT91_ADC_PRESCAL) |
> +			(AT91_ADC_STARTUP_(ticks)&  AT91_ADC_STARTUP));
> +
> +	/* Setup the ADC channels available on the board */
> +	ret = at91_adc_channel_init(idev);
> +	if (ret<  0) {
> +		dev_err(&pdev->dev, "Couldn't initialize the channels.\n");
> +		goto error_disable_adc_clk;
> +	}
> +
> +	init_waitqueue_head(&st->wq_data_avail);
> +	mutex_init(&st->lock);
> +
> +	ret = at91_adc_buffer_init(idev);
> +	if (ret<  0) {
> +		dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
> +		goto error_disable_adc_clk;
> +	}
> +
> +	ret = at91_adc_trigger_init(idev);
> +	if (ret<  0) {
> +		dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
> +		goto error_unregister_buffer;
> +	}
> +
> +	ret = iio_device_register(idev);
> +	if (ret<  0) {
> +		dev_err(&pdev->dev, "Couldn't register the device.\n");
> +		goto error_remove_triggers;
> +	}
> +
> +	return 0;
> +
> +error_remove_triggers:
> +	at91_adc_trigger_remove(idev);
> +error_unregister_buffer:
> +	at91_adc_buffer_remove(idev);
> +error_disable_adc_clk:
> +	clk_disable(st->adc_clk);
> +error_unprepare_adc_clk:
> +	clk_unprepare(st->adc_clk);
> +error_free_adc_clk:
> +	clk_put(st->adc_clk);
> +error_disable_clk:
> +	clk_disable(st->clk);
> +error_unprepare_clk:
> +	clk_unprepare(st->clk);
> +error_free_clk:
> +	clk_put(st->clk);
> +error_free_irq:
> +	free_irq(st->irq, idev);
> +error_unmap_reg:
> +	iounmap(st->reg_base);
> +error_release_mem:
> +	release_mem_region(res->start, resource_size(res));
> +error_free_device:
> +	iio_device_free(idev);
> +error_ret:
> +	return ret;
> +}
> +
> +static int __devexit at91_adc_remove(struct platform_device *pdev)
> +{
> +	struct iio_dev *idev = platform_get_drvdata(pdev);
> +	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	struct at91_adc_state *st = iio_priv(idev);
> +
> +	iio_device_unregister(idev);
> +	at91_adc_trigger_remove(idev);
> +	at91_adc_buffer_remove(idev);
There is clk_disable_unprepare... Could use it though then it's not 
quite as trivial to
check everything lines up between probe and remove.
> +	clk_disable(st->adc_clk);
> +	clk_unprepare(st->adc_clk);
> +	clk_put(st->adc_clk);
> +	clk_disable(st->clk);
> +	clk_unprepare(st->clk);
> +	clk_put(st->clk);
> +	free_irq(st->irq, idev);
> +	iounmap(st->reg_base);
> +	release_mem_region(res->start, resource_size(res));
> +	iio_device_free(idev);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver at91_adc_driver = {
> +	.probe = at91_adc_probe,
> +	.remove = __devexit_p(at91_adc_remove),
> +	.driver = {
> +		   .name = "at91_adc",
> +	},
> +};
> +
> +module_platform_driver(at91_adc_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("Atmel AT91 ADC Driver");
> +MODULE_AUTHOR("Maxime Ripard<maxime.ripard@free-electrons.com>");

[PATCH 2/9] ARM: AT91: IIO: Add AT91 ADC driver.

[Jonathan Cameron]

On 5/9/2012 2:02 PM, Maxime Ripard wrote:
> Add the ADC driver for Atmel's AT91SAM9G20-EK, AT91SAM9M10G45-EK
> and AT91SAM9X5 family boards.
>
> It has support for both software and hardware triggers.
Totally trivial, but please add a newline where it says below. 
Otherwise, looks
fine to me.  Couple of other passing comments inline, but nothing else 
to change
unless you particularly want to.
> Signed-off-by: Maxime Ripard<maxime.ripard@free-electrons.com>
> Acked-by: Nicolas Ferre<nicolas.ferre@atmel.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
>   drivers/iio/Kconfig        |    2 +
>   drivers/iio/Makefile       |    2 +
>   drivers/iio/adc/Kconfig    |   16 ++
>   drivers/iio/adc/Makefile   |    5 +
>   drivers/iio/adc/at91_adc.c |  673 ++++++++++++++++++++++++++++++++++++++++++++
>   5 files changed, 698 insertions(+)
>   create mode 100644 drivers/iio/adc/Kconfig
>   create mode 100644 drivers/iio/adc/Makefile
>   create mode 100644 drivers/iio/adc/at91_adc.c
>
> diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
> index 3ab7d48..47e0920 100644
> --- a/drivers/iio/Kconfig
> +++ b/drivers/iio/Kconfig
> @@ -48,4 +48,6 @@ config IIO_CONSUMERS_PER_TRIGGER
>   	This value controls the maximum number of consumers that a
>   	given trigger may handle. Default is 2.
>
> +source "drivers/iio/adc/Kconfig"
> +
>   endif # IIO
> diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
> index d5fc57d..eb926a2 100644
> --- a/drivers/iio/Makefile
> +++ b/drivers/iio/Makefile
> @@ -8,3 +8,5 @@ industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o
>   industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o
>
>   obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o
> +
> +obj-y += adc/
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> new file mode 100644
> index 0000000..9a0df81
> --- /dev/null
> +++ b/drivers/iio/adc/Kconfig
> @@ -0,0 +1,16 @@
> +#
> +# ADC drivers
> +#
> +menu "Analog to digital converters"
> +
> +config AT91_ADC
> +	tristate "Atmel AT91 ADC"
> +	depends on ARCH_AT91
> +	select IIO_BUFFER
> +	select IIO_KFIFO_BUF
> +	select IIO_TRIGGER
> +	select SYSFS
> +	help
> +	  Say yes here to build support for Atmel AT91 ADC.
> +
> +endmenu
> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
> new file mode 100644
> index 0000000..b62d488
> --- /dev/null
> +++ b/drivers/iio/adc/Makefile
> @@ -0,0 +1,5 @@
> +#
> +# Makefile for IIO ADC drivers
> +#
> +
> +obj-$(CONFIG_AT91_ADC) += at91_adc.o
Please add a newline here.
> \ No newline at end of file
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> new file mode 100644
> index 0000000..e5d73b1
> --- /dev/null
> +++ b/drivers/iio/adc/at91_adc.c
> @@ -0,0 +1,673 @@
> +/*
> + * Driver for the ADC present in the Atmel AT91 evaluation boards.
> + *
> + * Copyright 2011 Free Electrons
> + *
> + * Licensed under the GPLv2 or later.
> + */
> +
> +#include<linux/bitmap.h>
> +#include<linux/bitops.h>
> +#include<linux/clk.h>
> +#include<linux/err.h>
> +#include<linux/io.h>
> +#include<linux/interrupt.h>
> +#include<linux/jiffies.h>
> +#include<linux/kernel.h>
> +#include<linux/module.h>
> +#include<linux/platform_device.h>
> +#include<linux/sched.h>
> +#include<linux/slab.h>
> +#include<linux/wait.h>
> +
> +#include<linux/platform_data/at91_adc.h>
> +
> +#include<linux/iio/iio.h>
> +#include<linux/iio/buffer.h>
> +#include<linux/iio/kfifo_buf.h>
> +#include<linux/iio/trigger.h>
> +#include<linux/iio/trigger_consumer.h>
> +
> +#include<mach/at91_adc.h>
> +
> +#define AT91_ADC_CHAN(st, ch) \
> +	(st->registers->channel_base + (ch * 4))
> +#define at91_adc_readl(st, reg) \
> +	(readl_relaxed(st->reg_base + reg))
> +#define at91_adc_writel(st, reg, val) \
> +	(writel_relaxed(val, st->reg_base + reg))
> +
> +struct at91_adc_state {
> +	struct clk		*adc_clk;
> +	u16			*buffer;
> +	unsigned long		channels_mask;
> +	struct clk		*clk;
> +	bool			done;
> +	int			irq;
> +	bool			irq_enabled;
> +	u16			last_value;
> +	struct mutex		lock;
> +	u8			num_channels;
> +	void __iomem		*reg_base;
> +	struct at91_adc_reg_desc *registers;
> +	u8			startup_time;
> +	struct iio_trigger	**trig;
> +	struct at91_adc_trigger	*trigger_list;
> +	u32			trigger_number;
> +	bool			use_external;
> +	u32			vref_mv;
> +	wait_queue_head_t	wq_data_avail;
> +};
> +
> +static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
> +{
> +	struct iio_poll_func *pf = p;
> +	struct iio_dev *idev = pf->indio_dev;
> +	struct at91_adc_state *st = iio_priv(idev);
> +	struct iio_buffer *buffer = idev->buffer;
> +	int i, j = 0;
> +
> +	for (i = 0; i<  idev->masklength; i++) {
> +		if (!test_bit(i, idev->active_scan_mask))
> +			continue;
> +		st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, i));
> +		j++;
> +	}
> +
> +	if (idev->scan_timestamp) {
> +		s64 *timestamp = (s64 *)((u8 *)st->buffer +
> +					ALIGN(j, sizeof(s64)));
> +		*timestamp = pf->timestamp;
> +	}
> +
> +	buffer->access->store_to(buffer, (u8 *)st->buffer, pf->timestamp);
> +
> +	iio_trigger_notify_done(idev->trig);
> +	st->irq_enabled = true;
> +
> +	/* Needed to ACK the DRDY interruption */
> +	at91_adc_readl(st, AT91_ADC_LCDR);
> +
> +	enable_irq(st->irq);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t at91_adc_eoc_trigger(int irq, void *private)
> +{
> +	struct iio_dev *idev = private;
> +	struct at91_adc_state *st = iio_priv(idev);
> +	u32 status = at91_adc_readl(st, st->registers->status_register);
> +
> +	if (!(status&  st->registers->drdy_mask))
> +		return IRQ_HANDLED;
> +
> +	if (iio_buffer_enabled(idev)) {
> +		disable_irq_nosync(irq);
> +		st->irq_enabled = false;
> +		iio_trigger_poll(idev->trig, iio_get_time_ns());
> +	} else {
> +		st->last_value = at91_adc_readl(st, AT91_ADC_LCDR);
> +		st->done = true;
> +		wake_up_interruptible(&st->wq_data_avail);
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int at91_adc_channel_init(struct iio_dev *idev)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	struct iio_chan_spec *chan_array, *timestamp;
> +	int bit, idx = 0;
> +
> +	idev->num_channels = bitmap_weight(&st->channels_mask,
> +					   st->num_channels) + 1;
> +
> +	chan_array = devm_kzalloc(&idev->dev,
> +				  ((idev->num_channels + 1) *
> +					sizeof(struct iio_chan_spec)),
> +				  GFP_KERNEL);
> +
> +	if (!chan_array)
> +		return -ENOMEM;
> +
> +	for_each_set_bit(bit,&st->channels_mask, st->num_channels) {
> +		struct iio_chan_spec *chan = chan_array + idx;
> +
> +		chan->type = IIO_VOLTAGE;
> +		chan->indexed = 1;
> +		chan->channel = bit;
> +		chan->scan_index = idx;
> +		chan->scan_type.sign = 'u';
> +		chan->scan_type.realbits = 10;
> +		chan->scan_type.storagebits = 16;
> +		chan->info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT |
> +			IIO_CHAN_INFO_RAW_SEPARATE_BIT;
> +		idx++;
> +	}
> +	timestamp = chan_array + idx;
> +
> +	timestamp->type = IIO_TIMESTAMP;
> +	timestamp->channel = -1;
> +	timestamp->scan_index = idx;
> +	timestamp->scan_type.sign = 's';
> +	timestamp->scan_type.realbits = 64;
> +	timestamp->scan_type.storagebits = 64;
> +
> +	idev->channels = chan_array;
> +	return idev->num_channels;
> +}
> +
> +static u8 at91_adc_get_trigger_value_by_name(struct iio_dev *idev,
> +					     struct at91_adc_trigger *triggers,
> +					     const char *trigger_name)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	u8 value = 0;
> +	int i;
> +
> +	for (i = 0; i<  st->trigger_number; i++) {
> +		char *name = kasprintf(GFP_KERNEL,
> +				"%s-dev%d-%s",
> +				idev->name,
> +				idev->id,
> +				triggers[i].name);
> +		if (!name)
> +			return -ENOMEM;
> +
> +		if (strcmp(trigger_name, name) == 0) {
> +			value = triggers[i].value;
> +			kfree(name);
> +			break;
> +		}
> +
> +		kfree(name);
> +	}
> +
> +	return value;
> +}
> +
> +static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
> +{
> +	struct iio_dev *idev = trig->private_data;
> +	struct at91_adc_state *st = iio_priv(idev);
> +	struct iio_buffer *buffer = idev->buffer;
> +	struct at91_adc_reg_desc *reg = st->registers;
> +	u32 status = at91_adc_readl(st, reg->trigger_register);
> +	u8 value;
> +	u8 bit;
> +
> +	value = at91_adc_get_trigger_value_by_name(idev,
> +						   st->trigger_list,
> +						   idev->trig->name);
> +	if (value == 0)
> +		return -EINVAL;
> +
> +	if (state) {
> +		st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL);
> +		if (st->buffer == NULL)
> +			return -ENOMEM;
> +
> +		at91_adc_writel(st, reg->trigger_register,
> +				status | value);
> +
> +		for_each_set_bit(bit, buffer->scan_mask,
> +				 st->num_channels) {
> +			struct iio_chan_spec const *chan = idev->channels + bit;
> +			at91_adc_writel(st, AT91_ADC_CHER,
> +					AT91_ADC_CH(chan->channel));
> +		}
> +
> +		at91_adc_writel(st, AT91_ADC_IER, reg->drdy_mask);
> +
> +	} else {
> +		at91_adc_writel(st, AT91_ADC_IDR, reg->drdy_mask);
> +
> +		at91_adc_writel(st, reg->trigger_register,
> +				status&  ~value);
> +
> +		for_each_set_bit(bit, buffer->scan_mask,
> +				 st->num_channels) {
> +			struct iio_chan_spec const *chan = idev->channels + bit;
> +			at91_adc_writel(st, AT91_ADC_CHDR,
> +					AT91_ADC_CH(chan->channel));
> +		}
> +		kfree(st->buffer);
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct iio_trigger_ops at91_adc_trigger_ops = {
> +	.owner = THIS_MODULE,
> +	.set_trigger_state =&at91_adc_configure_trigger,
> +};
> +
> +static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *idev,
> +						     struct at91_adc_trigger *trigger)
> +{
> +	struct iio_trigger *trig;
> +	int ret;
> +
> +	trig = iio_trigger_alloc("%s-dev%d-%s", idev->name,
> +				 idev->id, trigger->name);
> +	if (trig == NULL)
> +		return NULL;
> +
> +	trig->dev.parent = idev->dev.parent;
> +	trig->private_data = idev;
> +	trig->ops =&at91_adc_trigger_ops;
> +
> +	ret = iio_trigger_register(trig);
> +	if (ret)
> +		return NULL;
> +
> +	return trig;
> +}
> +
> +static int at91_adc_trigger_init(struct iio_dev *idev)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	int i, ret;
> +
> +	st->trig = devm_kzalloc(&idev->dev,
> +				st->trigger_number * sizeof(st->trig),
> +				GFP_KERNEL);
> +
> +	if (st->trig == NULL) {
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	for (i = 0; i<  st->trigger_number; i++) {
> +		if (st->trigger_list[i].is_external&&  !(st->use_external))
> +			continue;
> +
> +		st->trig[i] = at91_adc_allocate_trigger(idev,
> +							st->trigger_list + i);
> +		if (st->trig[i] == NULL) {
> +			dev_err(&idev->dev,
> +				"Could not allocate trigger %d\n", i);
> +			ret = -ENOMEM;
> +			goto error_trigger;
> +		}
> +	}
> +
> +	return 0;
> +
> +error_trigger:
> +	for (i--; i>= 0; i--) {
> +		iio_trigger_unregister(st->trig[i]);
> +		iio_trigger_free(st->trig[i]);
> +	}
> +error_ret:
> +	return ret;
> +}
> +
> +static void at91_adc_trigger_remove(struct iio_dev *idev)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	int i;
> +
> +	for (i = 0; i<  st->trigger_number; i++) {
> +		iio_trigger_unregister(st->trig[i]);
> +		iio_trigger_free(st->trig[i]);
> +	}
> +}
> +
> +static const struct iio_buffer_setup_ops at91_adc_buffer_ops = {
> +	.preenable =&iio_sw_buffer_preenable,
> +	.postenable =&iio_triggered_buffer_postenable,
> +	.predisable =&iio_triggered_buffer_predisable,
> +};
> +
> +static int at91_adc_buffer_init(struct iio_dev *idev)
> +{
> +	int ret;
> +
> +	idev->buffer = iio_kfifo_allocate(idev);
> +	if (!idev->buffer) {
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	idev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time,
> +					&at91_adc_trigger_handler,
> +					    IRQF_ONESHOT,
> +					    idev,
> +					    "%s-consumer%d",
> +					    idev->name,
> +					    idev->id);
> +	if (idev->pollfunc == NULL) {
> +		ret = -ENOMEM;
> +		goto error_pollfunc;
> +	}
> +
> +	idev->setup_ops =&at91_adc_buffer_ops;
> +	idev->modes |= INDIO_BUFFER_TRIGGERED;
> +
> +	ret = iio_buffer_register(idev,
> +				  idev->channels,
> +				  idev->num_channels);
> +	if (ret)
> +		goto error_register;
> +
> +	return 0;
> +
> +error_register:
> +	iio_dealloc_pollfunc(idev->pollfunc);
> +error_pollfunc:
> +	iio_kfifo_free(idev->buffer);
> +error_ret:
> +	return ret;
> +}
> +
> +static void at91_adc_buffer_remove(struct iio_dev *idev)
> +{
> +	iio_buffer_unregister(idev);
> +	iio_dealloc_pollfunc(idev->pollfunc);
> +	iio_kfifo_free(idev->buffer);
> +}
> +
> +static int at91_adc_read_raw(struct iio_dev *idev,
> +			     struct iio_chan_spec const *chan,
> +			     int *val, int *val2, long mask)
> +{
> +	struct at91_adc_state *st = iio_priv(idev);
> +	int ret;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		mutex_lock(&st->lock);
> +
> +		at91_adc_writel(st, AT91_ADC_CHER,
> +				AT91_ADC_CH(chan->channel));
> +		at91_adc_writel(st, AT91_ADC_IER, st->registers->drdy_mask);
> +		at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_START);
> +
> +		ret = wait_event_interruptible_timeout(st->wq_data_avail,
> +						       st->done,
> +						       msecs_to_jiffies(1000));
> +		if (ret == 0)
> +			return -ETIMEDOUT;
> +		else if (ret<  0)
> +			return ret;
> +
> +		*val = st->last_value;
> +
> +		at91_adc_writel(st, AT91_ADC_CHDR,
> +				AT91_ADC_CH(chan->channel));
> +		at91_adc_writel(st, AT91_ADC_IDR, st->registers->drdy_mask);
> +
> +		st->last_value = 0;
> +		st->done = false;
> +		mutex_unlock(&st->lock);
> +		return IIO_VAL_INT;
> +
> +	case IIO_CHAN_INFO_SCALE:
> +		*val = (st->vref_mv * 1000)>>  chan->scan_type.realbits;
> +		*val2 = 0;
> +		return IIO_VAL_INT_PLUS_MICRO;
> +	default:
> +		break;
> +	}
> +	return -EINVAL;
> +}
> +
> +static int at91_adc_probe_pdata(struct at91_adc_state *st,
> +				struct platform_device *pdev)
> +{
> +	struct at91_adc_data *pdata = pdev->dev.platform_data;
> +
> +	if (!pdata)
> +		return -EINVAL;
> +
This does look rather like it would be better to just keep a copy of 
pdata around...
Still, not critical at all.
> +	st->use_external = pdata->use_external_triggers;
> +	st->vref_mv = pdata->vref;
> +	st->channels_mask = pdata->channels_used;
> +	st->num_channels = pdata->num_channels;
> +	st->startup_time = pdata->startup_time;
> +	st->trigger_number = pdata->trigger_number;
> +	st->trigger_list = pdata->trigger_list;
> +	st->registers = pdata->registers;
> +
> +	return 0;
> +}
> +
> +static const struct iio_info at91_adc_info = {
> +	.driver_module = THIS_MODULE,
> +	.read_raw =&at91_adc_read_raw,
> +};
> +
> +static int __devinit at91_adc_probe(struct platform_device *pdev)
> +{
> +	unsigned int prsc, mstrclk, ticks, adc_clk;
> +	int ret;
> +	struct iio_dev *idev;
> +	struct at91_adc_state *st;
> +	struct resource *res;
> +
> +	idev = iio_device_alloc(sizeof(struct at91_adc_state));
> +	if (idev == NULL) {
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	st = iio_priv(idev);
> +
> +	ret = at91_adc_probe_pdata(st, pdev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "No platform data available.\n");
> +		ret = -EINVAL;
> +		goto error_free_device;
> +	}
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev, "No resource defined\n");
> +		ret = -ENXIO;
> +		goto error_ret;
> +	}
> +
> +	platform_set_drvdata(pdev, idev);
> +
> +	idev->dev.parent =&pdev->dev;
> +	idev->name = dev_name(&pdev->dev);
> +	idev->modes = INDIO_DIRECT_MODE;
> +	idev->info =&at91_adc_info;
> +
> +	st->irq = platform_get_irq(pdev, 0);
> +	if (st->irq<  0) {
> +		dev_err(&pdev->dev, "No IRQ ID is designated\n");
> +		ret = -ENODEV;
> +		goto error_free_device;
> +	}
> +
> +	if (!request_mem_region(res->start, resource_size(res),
> +				"AT91 adc registers")) {
> +		dev_err(&pdev->dev, "Resources are unavailable.\n");
> +		ret = -EBUSY;
> +		goto error_free_device;
> +	}
> +
> +	st->reg_base = ioremap(res->start, resource_size(res));
> +	if (!st->reg_base) {
> +		dev_err(&pdev->dev, "Failed to map registers.\n");
> +		ret = -ENOMEM;
> +		goto error_release_mem;
> +	}
> +
> +	/*
> +	 * Disable all IRQs before setting up the handler
> +	 */
> +	at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST);
> +	at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF);
> +	ret = request_irq(st->irq,
> +			  at91_adc_eoc_trigger,
> +			  0,
> +			  pdev->dev.driver->name,
> +			  idev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to allocate IRQ.\n");
> +		goto error_unmap_reg;
> +	}
> +
> +	st->clk = clk_get(&pdev->dev, "adc_clk");
> +	if (IS_ERR(st->clk)) {
> +		dev_err(&pdev->dev, "Failed to get the clock.\n");
> +		ret = PTR_ERR(st->clk);
> +		goto error_free_irq;
> +	}
> +
> +	ret = clk_prepare(st->clk);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Could not prepare the clock.\n");
> +		goto error_free_clk;
> +	}
> +
> +	ret = clk_enable(st->clk);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Could not enable the clock.\n");
> +		goto error_unprepare_clk;
> +	}
> +
> +	st->adc_clk = clk_get(&pdev->dev, "adc_op_clk");
> +	if (IS_ERR(st->adc_clk)) {
> +		dev_err(&pdev->dev, "Failed to get the ADC clock.\n");
> +		ret = PTR_ERR(st->clk);
> +		goto error_disable_clk;
> +	}
> +
> +	ret = clk_prepare(st->adc_clk);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Could not prepare the ADC clock.\n");
> +		goto error_free_adc_clk;
> +	}
> +
> +	ret = clk_enable(st->adc_clk);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Could not enable the ADC clock.\n");
> +		goto error_unprepare_adc_clk;
> +	}
> +
> +	/*
> +	 * Prescaler rate computation using the formula from the Atmel's
> +	 * datasheet : ADC Clock = MCK / ((Prescaler + 1) * 2), ADC Clock being
> +	 * specified by the electrical characteristics of the board.
> +	 */
> +	mstrclk = clk_get_rate(st->clk);
> +	adc_clk = clk_get_rate(st->adc_clk);
> +	prsc = (mstrclk / (2 * adc_clk)) - 1;
> +
> +	if (!st->startup_time) {
> +		dev_err(&pdev->dev, "No startup time available.\n");
> +		ret = -EINVAL;
> +		goto error_disable_adc_clk;
> +	}
> +
> +	/*
> +	 * Number of ticks needed to cover the startup time of the ADC as
> +	 * defined in the electrical characteristics of the board, divided by 8.
> +	 * The formula thus is : Startup Time = (ticks + 1) * 8 / ADC Clock
> +	 */
> +	ticks = round_up((st->startup_time * adc_clk /
> +			  1000000) - 1, 8) / 8;
> +	at91_adc_writel(st, AT91_ADC_MR,
> +			(AT91_ADC_PRESCAL_(prsc)&  AT91_ADC_PRESCAL) |
> +			(AT91_ADC_STARTUP_(ticks)&  AT91_ADC_STARTUP));
> +
> +	/* Setup the ADC channels available on the board */
> +	ret = at91_adc_channel_init(idev);
> +	if (ret<  0) {
> +		dev_err(&pdev->dev, "Couldn't initialize the channels.\n");
> +		goto error_disable_adc_clk;
> +	}
> +
> +	init_waitqueue_head(&st->wq_data_avail);
> +	mutex_init(&st->lock);
> +
> +	ret = at91_adc_buffer_init(idev);
> +	if (ret<  0) {
> +		dev_err(&pdev->dev, "Couldn't initialize the buffer.\n");
> +		goto error_disable_adc_clk;
> +	}
> +
> +	ret = at91_adc_trigger_init(idev);
> +	if (ret<  0) {
> +		dev_err(&pdev->dev, "Couldn't setup the triggers.\n");
> +		goto error_unregister_buffer;
> +	}
> +
> +	ret = iio_device_register(idev);
> +	if (ret<  0) {
> +		dev_err(&pdev->dev, "Couldn't register the device.\n");
> +		goto error_remove_triggers;
> +	}
> +
> +	return 0;
> +
> +error_remove_triggers:
> +	at91_adc_trigger_remove(idev);
> +error_unregister_buffer:
> +	at91_adc_buffer_remove(idev);
> +error_disable_adc_clk:
> +	clk_disable(st->adc_clk);
> +error_unprepare_adc_clk:
> +	clk_unprepare(st->adc_clk);
> +error_free_adc_clk:
> +	clk_put(st->adc_clk);
> +error_disable_clk:
> +	clk_disable(st->clk);
> +error_unprepare_clk:
> +	clk_unprepare(st->clk);
> +error_free_clk:
> +	clk_put(st->clk);
> +error_free_irq:
> +	free_irq(st->irq, idev);
> +error_unmap_reg:
> +	iounmap(st->reg_base);
> +error_release_mem:
> +	release_mem_region(res->start, resource_size(res));
> +error_free_device:
> +	iio_device_free(idev);
> +error_ret:
> +	return ret;
> +}
> +
> +static int __devexit at91_adc_remove(struct platform_device *pdev)
> +{
> +	struct iio_dev *idev = platform_get_drvdata(pdev);
> +	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	struct at91_adc_state *st = iio_priv(idev);
> +
> +	iio_device_unregister(idev);
> +	at91_adc_trigger_remove(idev);
> +	at91_adc_buffer_remove(idev);
There is clk_disable_unprepare... Could use it though then it's not 
quite as trivial to
check everything lines up between probe and remove.
> +	clk_disable(st->adc_clk);
> +	clk_unprepare(st->adc_clk);
> +	clk_put(st->adc_clk);
> +	clk_disable(st->clk);
> +	clk_unprepare(st->clk);
> +	clk_put(st->clk);
> +	free_irq(st->irq, idev);
> +	iounmap(st->reg_base);
> +	release_mem_region(res->start, resource_size(res));
> +	iio_device_free(idev);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver at91_adc_driver = {
> +	.probe = at91_adc_probe,
> +	.remove = __devexit_p(at91_adc_remove),
> +	.driver = {
> +		   .name = "at91_adc",
> +	},
> +};
> +
> +module_platform_driver(at91_adc_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("Atmel AT91 ADC Driver");
> +MODULE_AUTHOR("Maxime Ripard<maxime.ripard@free-electrons.com>");

[PATCH 3/9] ARM: AT91: Add the ADC to the sam9g20ek board

[Maxime Ripard]

This patch adds platform data for the AT91 ADC driver support for
the AT91SAM9G20-EK board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/mach-at91/at91sam9260.c         |    8 +++
 arch/arm/mach-at91/at91sam9260_devices.c |   90 ++++++++++++++++++++++++++++++
 arch/arm/mach-at91/board-sam9g20ek.c     |   14 +++++
 3 files changed, 112 insertions(+)

diff --git a/arch/arm/mach-at91/at91sam9260.c b/arch/arm/mach-at91/at91sam9260.c
index 46f7742..63d4432 100644
--- a/arch/arm/mach-at91/at91sam9260.c
+++ b/arch/arm/mach-at91/at91sam9260.c
@@ -55,6 +55,13 @@ static struct clk adc_clk = {
 	.pmc_mask	= 1 << AT91SAM9260_ID_ADC,
 	.type		= CLK_TYPE_PERIPHERAL,
 };
+
+static struct clk adc_op_clk = {
+	.name		= "adc_op_clk",
+	.type		= CLK_TYPE_PERIPHERAL,
+	.rate_hz	= 5000000,
+};
+
 static struct clk usart0_clk = {
 	.name		= "usart0_clk",
 	.pmc_mask	= 1 << AT91SAM9260_ID_US0,
@@ -166,6 +173,7 @@ static struct clk *periph_clocks[] __initdata = {
 	&pioB_clk,
 	&pioC_clk,
 	&adc_clk,
+	&adc_op_clk,
 	&usart0_clk,
 	&usart1_clk,
 	&usart2_clk,
diff --git a/arch/arm/mach-at91/at91sam9260_devices.c b/arch/arm/mach-at91/at91sam9260_devices.c
index 5652dde..be0eb26 100644
--- a/arch/arm/mach-at91/at91sam9260_devices.c
+++ b/arch/arm/mach-at91/at91sam9260_devices.c
@@ -17,12 +17,15 @@
 #include <linux/platform_device.h>
 #include <linux/i2c-gpio.h>
 
+#include <linux/platform_data/at91_adc.h>
+
 #include <mach/board.h>
 #include <mach/cpu.h>
 #include <mach/at91sam9260.h>
 #include <mach/at91sam9260_matrix.h>
 #include <mach/at91_matrix.h>
 #include <mach/at91sam9_smc.h>
+#include <mach/at91_adc.h>
 
 #include "generic.h"
 
@@ -1369,6 +1372,93 @@ 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 IS_ENABLED(CONFIG_AT91_ADC)
+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),
+};
+
+static struct at91_adc_trigger at91_adc_triggers[] = {
+	[0] = {
+		.name = "timer-counter-0",
+		.value = AT91_ADC_TRGSEL_TC0 | AT91_ADC_TRGEN,
+	},
+	[1] = {
+		.name = "timer-counter-1",
+		.value = AT91_ADC_TRGSEL_TC1 | AT91_ADC_TRGEN,
+	},
+	[2] = {
+		.name = "timer-counter-2",
+		.value = AT91_ADC_TRGSEL_TC2 | AT91_ADC_TRGEN,
+	},
+	[3] = {
+		.name = "external",
+		.value = AT91_ADC_TRGSEL_EXTERNAL | AT91_ADC_TRGEN,
+		.is_external = true,
+	},
+};
+
+static struct at91_adc_reg_desc at91_adc_register_g20 = {
+	.channel_base = AT91_ADC_CHR(0),
+	.drdy_mask = AT91_ADC_DRDY,
+	.status_register = AT91_ADC_SR,
+	.trigger_register = AT91_ADC_MR,
+};
+
+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);
+
+	if (data->use_external_triggers)
+		at91_set_A_periph(AT91_PIN_PA22, 0);
+
+	data->num_channels = 4;
+	data->startup_time = 10;
+	data->registers = &at91_adc_register_g20;
+	data->trigger_number = 4;
+	data->trigger_list = at91_adc_triggers;
+
+	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 8923ec9..291b0fe 100644
--- a/arch/arm/mach-at91/board-sam9g20ek.c
+++ b/arch/arm/mach-at91/board-sam9g20ek.c
@@ -32,6 +32,8 @@
 #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>
@@ -318,6 +320,16 @@ 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),
+	.use_external_triggers = true,
+	.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"),
@@ -393,6 +405,8 @@ 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) */
-- 
1.7.9.5

[PATCH 3/9] ARM: AT91: Add the ADC to the sam9g20ek board

[Maxime Ripard]

This patch adds platform data for the AT91 ADC driver support for
the AT91SAM9G20-EK board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/mach-at91/at91sam9260.c         |    8 +++
 arch/arm/mach-at91/at91sam9260_devices.c |   90 ++++++++++++++++++++++++++++++
 arch/arm/mach-at91/board-sam9g20ek.c     |   14 +++++
 3 files changed, 112 insertions(+)

diff --git a/arch/arm/mach-at91/at91sam9260.c b/arch/arm/mach-at91/at91sam9260.c
index 46f7742..63d4432 100644
--- a/arch/arm/mach-at91/at91sam9260.c
+++ b/arch/arm/mach-at91/at91sam9260.c
@@ -55,6 +55,13 @@ static struct clk adc_clk = {
 	.pmc_mask	= 1 << AT91SAM9260_ID_ADC,
 	.type		= CLK_TYPE_PERIPHERAL,
 };
+
+static struct clk adc_op_clk = {
+	.name		= "adc_op_clk",
+	.type		= CLK_TYPE_PERIPHERAL,
+	.rate_hz	= 5000000,
+};
+
 static struct clk usart0_clk = {
 	.name		= "usart0_clk",
 	.pmc_mask	= 1 << AT91SAM9260_ID_US0,
@@ -166,6 +173,7 @@ static struct clk *periph_clocks[] __initdata = {
 	&pioB_clk,
 	&pioC_clk,
 	&adc_clk,
+	&adc_op_clk,
 	&usart0_clk,
 	&usart1_clk,
 	&usart2_clk,
diff --git a/arch/arm/mach-at91/at91sam9260_devices.c b/arch/arm/mach-at91/at91sam9260_devices.c
index 5652dde..be0eb26 100644
--- a/arch/arm/mach-at91/at91sam9260_devices.c
+++ b/arch/arm/mach-at91/at91sam9260_devices.c
@@ -17,12 +17,15 @@
 #include <linux/platform_device.h>
 #include <linux/i2c-gpio.h>
 
+#include <linux/platform_data/at91_adc.h>
+
 #include <mach/board.h>
 #include <mach/cpu.h>
 #include <mach/at91sam9260.h>
 #include <mach/at91sam9260_matrix.h>
 #include <mach/at91_matrix.h>
 #include <mach/at91sam9_smc.h>
+#include <mach/at91_adc.h>
 
 #include "generic.h"
 
@@ -1369,6 +1372,93 @@ 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 IS_ENABLED(CONFIG_AT91_ADC)
+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),
+};
+
+static struct at91_adc_trigger at91_adc_triggers[] = {
+	[0] = {
+		.name = "timer-counter-0",
+		.value = AT91_ADC_TRGSEL_TC0 | AT91_ADC_TRGEN,
+	},
+	[1] = {
+		.name = "timer-counter-1",
+		.value = AT91_ADC_TRGSEL_TC1 | AT91_ADC_TRGEN,
+	},
+	[2] = {
+		.name = "timer-counter-2",
+		.value = AT91_ADC_TRGSEL_TC2 | AT91_ADC_TRGEN,
+	},
+	[3] = {
+		.name = "external",
+		.value = AT91_ADC_TRGSEL_EXTERNAL | AT91_ADC_TRGEN,
+		.is_external = true,
+	},
+};
+
+static struct at91_adc_reg_desc at91_adc_register_g20 = {
+	.channel_base = AT91_ADC_CHR(0),
+	.drdy_mask = AT91_ADC_DRDY,
+	.status_register = AT91_ADC_SR,
+	.trigger_register = AT91_ADC_MR,
+};
+
+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);
+
+	if (data->use_external_triggers)
+		at91_set_A_periph(AT91_PIN_PA22, 0);
+
+	data->num_channels = 4;
+	data->startup_time = 10;
+	data->registers = &at91_adc_register_g20;
+	data->trigger_number = 4;
+	data->trigger_list = at91_adc_triggers;
+
+	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 8923ec9..291b0fe 100644
--- a/arch/arm/mach-at91/board-sam9g20ek.c
+++ b/arch/arm/mach-at91/board-sam9g20ek.c
@@ -32,6 +32,8 @@
 #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>
@@ -318,6 +320,16 @@ 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),
+	.use_external_triggers = true,
+	.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"),
@@ -393,6 +405,8 @@ 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) */
-- 
1.7.9.5

[PATCH 4/9] AT91: ADC: Add support for the AT91SAM9M10G45-EK board

[Maxime Ripard]

This patch adds platform data for the AT91 ADC driver support for
the AT91SAM9M10G45-EK board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/mach-at91/at91sam9g45.c         |    9 +++
 arch/arm/mach-at91/at91sam9g45_devices.c |  101 ++++++++++++++++++++++++++++++
 arch/arm/mach-at91/board-sam9m10g45ek.c  |   12 ++++
 3 files changed, 122 insertions(+)

diff --git a/arch/arm/mach-at91/at91sam9g45.c b/arch/arm/mach-at91/at91sam9g45.c
index d222f83..30865c6 100644
--- a/arch/arm/mach-at91/at91sam9g45.c
+++ b/arch/arm/mach-at91/at91sam9g45.c
@@ -176,6 +176,12 @@ static struct clk vdec_clk = {
 	.type		= CLK_TYPE_PERIPHERAL,
 };
 
+static struct clk adc_op_clk = {
+	.name		= "adc_op_clk",
+	.type		= CLK_TYPE_PERIPHERAL,
+	.rate_hz	= 13200000,
+};
+
 static struct clk *periph_clocks[] __initdata = {
 	&pioA_clk,
 	&pioB_clk,
@@ -204,6 +210,7 @@ static struct clk *periph_clocks[] __initdata = {
 	&isi_clk,
 	&udphs_clk,
 	&mmc1_clk,
+	&adc_op_clk,
 	// irq0
 };
 
@@ -242,6 +249,8 @@ static struct clk_lookup periph_clocks_lookups[] = {
 	CLKDEV_CON_ID("pioC", &pioC_clk),
 	CLKDEV_CON_ID("pioD", &pioDE_clk),
 	CLKDEV_CON_ID("pioE", &pioDE_clk),
+	/* Fake adc clock */
+	CLKDEV_CON_ID("adc_clk", &tsc_clk),
 };
 
 static struct clk_lookup usart_clocks_lookups[] = {
diff --git a/arch/arm/mach-at91/at91sam9g45_devices.c b/arch/arm/mach-at91/at91sam9g45_devices.c
index 6b008ae..0c6d9fe 100644
--- a/arch/arm/mach-at91/at91sam9g45_devices.c
+++ b/arch/arm/mach-at91/at91sam9g45_devices.c
@@ -19,9 +19,12 @@
 #include <linux/i2c-gpio.h>
 #include <linux/atmel-mci.h>
 
+#include <linux/platform_data/at91_adc.h>
+
 #include <linux/fb.h>
 #include <video/atmel_lcdc.h>
 
+#include <mach/at91_adc.h>
 #include <mach/board.h>
 #include <mach/at91sam9g45.h>
 #include <mach/at91sam9g45_matrix.h>
@@ -1207,6 +1210,104 @@ void __init at91_add_device_tsadcc(struct at91_tsadcc_data *data) {}
 
 
 /* --------------------------------------------------------------------
+ *  ADC
+ * -------------------------------------------------------------------- */
+
+#if IS_ENABLED(CONFIG_AT91_ADC)
+static struct at91_adc_data adc_data;
+
+static struct resource adc_resources[] = {
+	[0] = {
+		.start	= AT91SAM9G45_BASE_TSC,
+		.end	= AT91SAM9G45_BASE_TSC + SZ_16K - 1,
+		.flags	= IORESOURCE_MEM,
+	},
+	[1] = {
+		.start	= AT91SAM9G45_ID_TSC,
+		.end	= AT91SAM9G45_ID_TSC,
+		.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),
+};
+
+static struct at91_adc_trigger at91_adc_triggers[] = {
+	[0] = {
+		.name = "external-rising",
+		.value = 1,
+		.is_external = true,
+	},
+	[1] = {
+		.name = "external-falling",
+		.value = 2,
+		.is_external = true,
+	},
+	[2] = {
+		.name = "external-any",
+		.value = 3,
+		.is_external = true,
+	},
+	[3] = {
+		.name = "continuous",
+		.value = 6,
+		.is_external = false,
+	},
+};
+
+static struct at91_adc_reg_desc at91_adc_register_g45 = {
+	.channel_base = AT91_ADC_CHR(0),
+	.drdy_mask = AT91_ADC_DRDY,
+	.status_register = AT91_ADC_SR,
+	.trigger_register = 0x08,
+};
+
+void __init at91_add_device_adc(struct at91_adc_data *data)
+{
+	if (!data)
+		return;
+
+	if (test_bit(0, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD20, 0);
+	if (test_bit(1, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD21, 0);
+	if (test_bit(2, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD22, 0);
+	if (test_bit(3, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD23, 0);
+	if (test_bit(4, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD24, 0);
+	if (test_bit(5, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD25, 0);
+	if (test_bit(6, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD26, 0);
+	if (test_bit(7, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD27, 0);
+
+	if (data->use_external_triggers)
+		at91_set_A_periph(AT91_PIN_PD28, 0);
+
+	data->num_channels = 8;
+	data->startup_time = 40;
+	data->registers = &at91_adc_register_g45;
+	data->trigger_number = 4;
+	data->trigger_list = at91_adc_triggers;
+
+	adc_data = *data;
+	platform_device_register(&at91_adc_device);
+}
+#else
+void __init at91_add_device_adc(struct at91_adc_data *data) {}
+#endif
+
+/* --------------------------------------------------------------------
  *  RTT
  * -------------------------------------------------------------------- */
 
diff --git a/arch/arm/mach-at91/board-sam9m10g45ek.c b/arch/arm/mach-at91/board-sam9m10g45ek.c
index c88e908..337abd2 100644
--- a/arch/arm/mach-at91/board-sam9m10g45ek.c
+++ b/arch/arm/mach-at91/board-sam9m10g45ek.c
@@ -27,6 +27,8 @@
 #include <linux/atmel-mci.h>
 #include <linux/delay.h>
 
+#include <linux/platform_data/at91_adc.h>
+
 #include <mach/hardware.h>
 #include <video/atmel_lcdc.h>
 #include <media/soc_camera.h>
@@ -315,6 +317,14 @@ static struct at91_tsadcc_data ek_tsadcc_data = {
 	.ts_sample_hold_time	= 0x0a,
 };
 
+/*
+ * ADCs
+ */
+static struct at91_adc_data ek_adc_data = {
+	.channels_used = BIT(0) | BIT(1) | BIT(2) | BIT(3) | BIT(4) | BIT(5) | BIT(6) | BIT(7),
+	.use_external_triggers = true,
+	.vref = 3300,
+};
 
 /*
  * GPIO Buttons
@@ -480,6 +490,8 @@ static void __init ek_board_init(void)
 	at91_add_device_lcdc(&ek_lcdc_data);
 	/* Touch Screen */
 	at91_add_device_tsadcc(&ek_tsadcc_data);
+	/* ADC */
+	at91_add_device_adc(&ek_adc_data);
 	/* Push Buttons */
 	ek_add_device_buttons();
 	/* AC97 */
-- 
1.7.9.5

[PATCH 4/9] AT91: ADC: Add support for the AT91SAM9M10G45-EK board

[Maxime Ripard]

This patch adds platform data for the AT91 ADC driver support for
the AT91SAM9M10G45-EK board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/mach-at91/at91sam9g45.c         |    9 +++
 arch/arm/mach-at91/at91sam9g45_devices.c |  101 ++++++++++++++++++++++++++++++
 arch/arm/mach-at91/board-sam9m10g45ek.c  |   12 ++++
 3 files changed, 122 insertions(+)

diff --git a/arch/arm/mach-at91/at91sam9g45.c b/arch/arm/mach-at91/at91sam9g45.c
index d222f83..30865c6 100644
--- a/arch/arm/mach-at91/at91sam9g45.c
+++ b/arch/arm/mach-at91/at91sam9g45.c
@@ -176,6 +176,12 @@ static struct clk vdec_clk = {
 	.type		= CLK_TYPE_PERIPHERAL,
 };
 
+static struct clk adc_op_clk = {
+	.name		= "adc_op_clk",
+	.type		= CLK_TYPE_PERIPHERAL,
+	.rate_hz	= 13200000,
+};
+
 static struct clk *periph_clocks[] __initdata = {
 	&pioA_clk,
 	&pioB_clk,
@@ -204,6 +210,7 @@ static struct clk *periph_clocks[] __initdata = {
 	&isi_clk,
 	&udphs_clk,
 	&mmc1_clk,
+	&adc_op_clk,
 	// irq0
 };
 
@@ -242,6 +249,8 @@ static struct clk_lookup periph_clocks_lookups[] = {
 	CLKDEV_CON_ID("pioC", &pioC_clk),
 	CLKDEV_CON_ID("pioD", &pioDE_clk),
 	CLKDEV_CON_ID("pioE", &pioDE_clk),
+	/* Fake adc clock */
+	CLKDEV_CON_ID("adc_clk", &tsc_clk),
 };
 
 static struct clk_lookup usart_clocks_lookups[] = {
diff --git a/arch/arm/mach-at91/at91sam9g45_devices.c b/arch/arm/mach-at91/at91sam9g45_devices.c
index 6b008ae..0c6d9fe 100644
--- a/arch/arm/mach-at91/at91sam9g45_devices.c
+++ b/arch/arm/mach-at91/at91sam9g45_devices.c
@@ -19,9 +19,12 @@
 #include <linux/i2c-gpio.h>
 #include <linux/atmel-mci.h>
 
+#include <linux/platform_data/at91_adc.h>
+
 #include <linux/fb.h>
 #include <video/atmel_lcdc.h>
 
+#include <mach/at91_adc.h>
 #include <mach/board.h>
 #include <mach/at91sam9g45.h>
 #include <mach/at91sam9g45_matrix.h>
@@ -1207,6 +1210,104 @@ void __init at91_add_device_tsadcc(struct at91_tsadcc_data *data) {}
 
 
 /* --------------------------------------------------------------------
+ *  ADC
+ * -------------------------------------------------------------------- */
+
+#if IS_ENABLED(CONFIG_AT91_ADC)
+static struct at91_adc_data adc_data;
+
+static struct resource adc_resources[] = {
+	[0] = {
+		.start	= AT91SAM9G45_BASE_TSC,
+		.end	= AT91SAM9G45_BASE_TSC + SZ_16K - 1,
+		.flags	= IORESOURCE_MEM,
+	},
+	[1] = {
+		.start	= AT91SAM9G45_ID_TSC,
+		.end	= AT91SAM9G45_ID_TSC,
+		.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),
+};
+
+static struct at91_adc_trigger at91_adc_triggers[] = {
+	[0] = {
+		.name = "external-rising",
+		.value = 1,
+		.is_external = true,
+	},
+	[1] = {
+		.name = "external-falling",
+		.value = 2,
+		.is_external = true,
+	},
+	[2] = {
+		.name = "external-any",
+		.value = 3,
+		.is_external = true,
+	},
+	[3] = {
+		.name = "continuous",
+		.value = 6,
+		.is_external = false,
+	},
+};
+
+static struct at91_adc_reg_desc at91_adc_register_g45 = {
+	.channel_base = AT91_ADC_CHR(0),
+	.drdy_mask = AT91_ADC_DRDY,
+	.status_register = AT91_ADC_SR,
+	.trigger_register = 0x08,
+};
+
+void __init at91_add_device_adc(struct at91_adc_data *data)
+{
+	if (!data)
+		return;
+
+	if (test_bit(0, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD20, 0);
+	if (test_bit(1, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD21, 0);
+	if (test_bit(2, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD22, 0);
+	if (test_bit(3, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD23, 0);
+	if (test_bit(4, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD24, 0);
+	if (test_bit(5, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD25, 0);
+	if (test_bit(6, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD26, 0);
+	if (test_bit(7, &data->channels_used))
+		at91_set_gpio_input(AT91_PIN_PD27, 0);
+
+	if (data->use_external_triggers)
+		at91_set_A_periph(AT91_PIN_PD28, 0);
+
+	data->num_channels = 8;
+	data->startup_time = 40;
+	data->registers = &at91_adc_register_g45;
+	data->trigger_number = 4;
+	data->trigger_list = at91_adc_triggers;
+
+	adc_data = *data;
+	platform_device_register(&at91_adc_device);
+}
+#else
+void __init at91_add_device_adc(struct at91_adc_data *data) {}
+#endif
+
+/* --------------------------------------------------------------------
  *  RTT
  * -------------------------------------------------------------------- */
 
diff --git a/arch/arm/mach-at91/board-sam9m10g45ek.c b/arch/arm/mach-at91/board-sam9m10g45ek.c
index c88e908..337abd2 100644
--- a/arch/arm/mach-at91/board-sam9m10g45ek.c
+++ b/arch/arm/mach-at91/board-sam9m10g45ek.c
@@ -27,6 +27,8 @@
 #include <linux/atmel-mci.h>
 #include <linux/delay.h>
 
+#include <linux/platform_data/at91_adc.h>
+
 #include <mach/hardware.h>
 #include <video/atmel_lcdc.h>
 #include <media/soc_camera.h>
@@ -315,6 +317,14 @@ static struct at91_tsadcc_data ek_tsadcc_data = {
 	.ts_sample_hold_time	= 0x0a,
 };
 
+/*
+ * ADCs
+ */
+static struct at91_adc_data ek_adc_data = {
+	.channels_used = BIT(0) | BIT(1) | BIT(2) | BIT(3) | BIT(4) | BIT(5) | BIT(6) | BIT(7),
+	.use_external_triggers = true,
+	.vref = 3300,
+};
 
 /*
  * GPIO Buttons
@@ -480,6 +490,8 @@ static void __init ek_board_init(void)
 	at91_add_device_lcdc(&ek_lcdc_data);
 	/* Touch Screen */
 	at91_add_device_tsadcc(&ek_tsadcc_data);
+	/* ADC */
+	at91_add_device_adc(&ek_adc_data);
 	/* Push Buttons */
 	ek_add_device_buttons();
 	/* AC97 */
-- 
1.7.9.5

[PATCH 5/9] ARM: AT91: Add the ADC clock to the sam9x5 SoC file

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/mach-at91/at91sam9x5.c |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm/mach-at91/at91sam9x5.c b/arch/arm/mach-at91/at91sam9x5.c
index 13c8cae..1b144b4 100644
--- a/arch/arm/mach-at91/at91sam9x5.c
+++ b/arch/arm/mach-at91/at91sam9x5.c
@@ -120,6 +120,11 @@ static struct clk adc_clk = {
 	.pmc_mask	= 1 << AT91SAM9X5_ID_ADC,
 	.type	= CLK_TYPE_PERIPHERAL,
 };
+static struct clk adc_op_clk = {
+	.name		= "adc_op_clk",
+	.type		= CLK_TYPE_PERIPHERAL,
+	.rate_hz	= 5000000,
+};
 static struct clk dma0_clk = {
 	.name		= "dma0_clk",
 	.pmc_mask	= 1 << AT91SAM9X5_ID_DMA0,
@@ -205,6 +210,7 @@ static struct clk *periph_clocks[] __initdata = {
 	&tcb0_clk,
 	&pwm_clk,
 	&adc_clk,
+	&adc_op_clk,
 	&dma0_clk,
 	&dma1_clk,
 	&uhphs_clk,
-- 
1.7.9.5

[PATCH 5/9] ARM: AT91: Add the ADC clock to the sam9x5 SoC file

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/mach-at91/at91sam9x5.c |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm/mach-at91/at91sam9x5.c b/arch/arm/mach-at91/at91sam9x5.c
index 13c8cae..1b144b4 100644
--- a/arch/arm/mach-at91/at91sam9x5.c
+++ b/arch/arm/mach-at91/at91sam9x5.c
@@ -120,6 +120,11 @@ static struct clk adc_clk = {
 	.pmc_mask	= 1 << AT91SAM9X5_ID_ADC,
 	.type	= CLK_TYPE_PERIPHERAL,
 };
+static struct clk adc_op_clk = {
+	.name		= "adc_op_clk",
+	.type		= CLK_TYPE_PERIPHERAL,
+	.rate_hz	= 5000000,
+};
 static struct clk dma0_clk = {
 	.name		= "dma0_clk",
 	.pmc_mask	= 1 << AT91SAM9X5_ID_DMA0,
@@ -205,6 +210,7 @@ static struct clk *periph_clocks[] __initdata = {
 	&tcb0_clk,
 	&pwm_clk,
 	&adc_clk,
+	&adc_op_clk,
 	&dma0_clk,
 	&dma1_clk,
 	&uhphs_clk,
-- 
1.7.9.5

[PATCH 6/9] IIO: AT91: Add DT support to at91_adc driver

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 .../devicetree/bindings/arm/atmel-adc.txt          |   65 ++++++++++
 drivers/iio/adc/at91_adc.c                         |  132 +++++++++++++++++++-
 2 files changed, 196 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/arm/atmel-adc.txt

diff --git a/Documentation/devicetree/bindings/arm/atmel-adc.txt b/Documentation/devicetree/bindings/arm/atmel-adc.txt
new file mode 100644
index 0000000..c63097d
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/atmel-adc.txt
@@ -0,0 +1,65 @@
+* AT91's Analog to Digital Converter (ADC)
+
+Required properties:
+  - compatible: Should be "atmel,at91sam9260-adc"
+  - reg: Should contain ADC registers location and length
+  - interrupts: Should contain the IRQ line for the ADC
+  - atmel,adc-channel-base: Offset of the first channel data register
+  - atmel,adc-channels-used: Bitmask of the channels muxed and enable for this
+    device
+  - atmel,adc-drdy-mask: Mask of the DRDY interruption in the ADC
+  - atmel,adc-num-channels: Number of channels available in the ADC
+  - atmel,adc-startup-time: Startup Time of the ADC in microseconds as
+    defined in the datasheet
+  - atmel,adc-status-register: Offset of the Interrupt Status Register
+  - atmel,adc-trigger-register: Offset of the Trigger Register
+  - atmel,adc-vref: Reference voltage in millivolts for the conversions
+
+Optional properties:
+  - atmel,adc-use-external: Boolean to enable of external triggers
+ 
+Optional trigger Nodes:
+  - Required properties:
+    * trigger-name: Name of the trigger exposed to the user
+    * trigger-value: Value to put in the Trigger register
+      to activate this trigger
+  - Optional properties:
+    * trigger-external: Is the trigger an external trigger?
+
+Examples:
+adc0: adc@fffb0000 {
+	compatible = "atmel,at91sam9260-adc";
+	reg = <0xfffb0000 0x100>;
+	interrupts = <20 4>;
+	atmel,adc-channel-base = <0x30>;
+	atmel,adc-channels-used = <0xff>;
+	atmel,adc-drdy-mask = <0x10000>;
+	atmel,adc-num-channels = <8>;
+	atmel,adc-startup-time = <40>;
+	atmel,adc-status-register = <0x1c>;
+	atmel,adc-trigger-register = <0x08>;
+	atmel,adc-use-external;
+	atmel,adc-vref = <3300>;
+
+	trigger@0 {
+		trigger-name = "external-rising";
+		trigger-value = <0x1>;
+		trigger-external;
+	};
+	trigger@1 {
+		trigger-name = "external-falling";
+		trigger-value = <0x2>;
+		trigger-external;
+	};
+
+	trigger@2 {
+		trigger-name = "external-any";
+		trigger-value = <0x3>;
+		trigger-external;
+	};
+
+	trigger@3 {
+		trigger-name = "continuous";
+		trigger-value = <0x6>;
+	};
+};
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index e5d73b1..d2eca64 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -15,6 +15,8 @@
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
@@ -415,6 +417,123 @@ static int at91_adc_read_raw(struct iio_dev *idev,
 	return -EINVAL;
 }
 
+static int at91_adc_probe_dt(struct at91_adc_state *st,
+			     struct platform_device *pdev)
+{
+	struct iio_dev *idev = iio_priv_to_dev(st);
+	struct device_node *node = pdev->dev.of_node;
+	struct device_node *trig_node;
+	int i = 0, ret;
+	u32 prop;
+
+	if (!node)
+		return -EINVAL;
+
+	st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers");
+
+	if (of_property_read_u32(node, "atmel,adc-channels-used", &prop)) {
+		dev_err(&idev->dev, "Missing adc-channels-used property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->channels_mask = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-num-channels", &prop)) {
+		dev_err(&idev->dev, "Missing adc-num-channels property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->num_channels = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-startup-time", &prop)) {
+		dev_err(&idev->dev, "Missing adc-startup-time property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->startup_time = prop;
+
+
+	if (of_property_read_u32(node, "atmel,adc-vref", &prop)) {
+		dev_err(&idev->dev, "Missing adc-vref property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->vref_mv = prop;
+
+	st->registers = devm_kzalloc(&idev->dev,
+				     sizeof(struct at91_adc_reg_desc),
+				     GFP_KERNEL);
+	if (!st->registers) {
+		dev_err(&idev->dev, "Could not allocate register memory.\n");
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	if (of_property_read_u32(node, "atmel,adc-channel-base", &prop)) {
+		dev_err(&idev->dev, "Missing adc-channel-base property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->registers->channel_base = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-drdy-mask", &prop)) {
+		dev_err(&idev->dev, "Missing adc-drdy-mask property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->registers->drdy_mask = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-status-register", &prop)) {
+		dev_err(&idev->dev, "Missing adc-status-register property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->registers->status_register = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-trigger-register", &prop)) {
+		dev_err(&idev->dev, "Missing adc-trigger-register property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->registers->trigger_register = prop;
+
+	st->trigger_number = of_get_child_count(node);
+	st->trigger_list = devm_kzalloc(&idev->dev, st->trigger_number *
+					sizeof(struct at91_adc_trigger),
+					GFP_KERNEL);
+	if (!st->trigger_list) {
+		dev_err(&idev->dev, "Could not allocate trigger list memory.\n");
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	for_each_child_of_node(node, trig_node) {
+		struct at91_adc_trigger *trig = st->trigger_list + i;
+		const char *name;
+
+		if (of_property_read_string(trig_node, "trigger-name", &name)) {
+			dev_err(&idev->dev, "Missing trigger-name property in the DT.\n");
+			ret = -EINVAL;
+			goto error_ret;
+		}
+	        trig->name = name;
+
+		if (of_property_read_u32(trig_node, "trigger-value", &prop)) {
+			dev_err(&idev->dev, "Missing trigger-value property in the DT.\n");
+			ret = -EINVAL;
+			goto error_ret;
+		}
+	        trig->value = prop;
+		trig->is_external = of_property_read_bool(trig_node, "trigger-external");
+		i++;
+	}
+
+	return 0;
+
+error_ret:
+	return ret;
+}
+
 static int at91_adc_probe_pdata(struct at91_adc_state *st,
 				struct platform_device *pdev)
 {
@@ -456,7 +575,11 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
 
 	st = iio_priv(idev);
 
-	ret = at91_adc_probe_pdata(st, pdev);
+	if (pdev->dev.of_node)
+		ret = at91_adc_probe_dt(st, pdev);
+	else
+		ret = at91_adc_probe_pdata(st, pdev);
+
 	if (ret) {
 		dev_err(&pdev->dev, "No platform data available.\n");
 		ret = -EINVAL;
@@ -658,11 +781,18 @@ static int __devexit at91_adc_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct of_device_id at91_adc_dt_ids[] = {
+	{ .compatible = "atmel,at91sam9260-adc" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, at91_adc_dt_ids);
+
 static struct platform_driver at91_adc_driver = {
 	.probe = at91_adc_probe,
 	.remove = __devexit_p(at91_adc_remove),
 	.driver = {
 		   .name = "at91_adc",
+		   .of_match_table = of_match_ptr(at91_adc_dt_ids),
 	},
 };
 
-- 
1.7.9.5

[PATCH 6/9] IIO: AT91: Add DT support to at91_adc driver

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 .../devicetree/bindings/arm/atmel-adc.txt          |   65 ++++++++++
 drivers/iio/adc/at91_adc.c                         |  132 +++++++++++++++++++-
 2 files changed, 196 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/arm/atmel-adc.txt

diff --git a/Documentation/devicetree/bindings/arm/atmel-adc.txt b/Documentation/devicetree/bindings/arm/atmel-adc.txt
new file mode 100644
index 0000000..c63097d
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/atmel-adc.txt
@@ -0,0 +1,65 @@
+* AT91's Analog to Digital Converter (ADC)
+
+Required properties:
+  - compatible: Should be "atmel,at91sam9260-adc"
+  - reg: Should contain ADC registers location and length
+  - interrupts: Should contain the IRQ line for the ADC
+  - atmel,adc-channel-base: Offset of the first channel data register
+  - atmel,adc-channels-used: Bitmask of the channels muxed and enable for this
+    device
+  - atmel,adc-drdy-mask: Mask of the DRDY interruption in the ADC
+  - atmel,adc-num-channels: Number of channels available in the ADC
+  - atmel,adc-startup-time: Startup Time of the ADC in microseconds as
+    defined in the datasheet
+  - atmel,adc-status-register: Offset of the Interrupt Status Register
+  - atmel,adc-trigger-register: Offset of the Trigger Register
+  - atmel,adc-vref: Reference voltage in millivolts for the conversions
+
+Optional properties:
+  - atmel,adc-use-external: Boolean to enable of external triggers
+ 
+Optional trigger Nodes:
+  - Required properties:
+    * trigger-name: Name of the trigger exposed to the user
+    * trigger-value: Value to put in the Trigger register
+      to activate this trigger
+  - Optional properties:
+    * trigger-external: Is the trigger an external trigger?
+
+Examples:
+adc0: adc at fffb0000 {
+	compatible = "atmel,at91sam9260-adc";
+	reg = <0xfffb0000 0x100>;
+	interrupts = <20 4>;
+	atmel,adc-channel-base = <0x30>;
+	atmel,adc-channels-used = <0xff>;
+	atmel,adc-drdy-mask = <0x10000>;
+	atmel,adc-num-channels = <8>;
+	atmel,adc-startup-time = <40>;
+	atmel,adc-status-register = <0x1c>;
+	atmel,adc-trigger-register = <0x08>;
+	atmel,adc-use-external;
+	atmel,adc-vref = <3300>;
+
+	trigger at 0 {
+		trigger-name = "external-rising";
+		trigger-value = <0x1>;
+		trigger-external;
+	};
+	trigger at 1 {
+		trigger-name = "external-falling";
+		trigger-value = <0x2>;
+		trigger-external;
+	};
+
+	trigger at 2 {
+		trigger-name = "external-any";
+		trigger-value = <0x3>;
+		trigger-external;
+	};
+
+	trigger at 3 {
+		trigger-name = "continuous";
+		trigger-value = <0x6>;
+	};
+};
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index e5d73b1..d2eca64 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -15,6 +15,8 @@
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
@@ -415,6 +417,123 @@ static int at91_adc_read_raw(struct iio_dev *idev,
 	return -EINVAL;
 }
 
+static int at91_adc_probe_dt(struct at91_adc_state *st,
+			     struct platform_device *pdev)
+{
+	struct iio_dev *idev = iio_priv_to_dev(st);
+	struct device_node *node = pdev->dev.of_node;
+	struct device_node *trig_node;
+	int i = 0, ret;
+	u32 prop;
+
+	if (!node)
+		return -EINVAL;
+
+	st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers");
+
+	if (of_property_read_u32(node, "atmel,adc-channels-used", &prop)) {
+		dev_err(&idev->dev, "Missing adc-channels-used property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->channels_mask = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-num-channels", &prop)) {
+		dev_err(&idev->dev, "Missing adc-num-channels property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->num_channels = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-startup-time", &prop)) {
+		dev_err(&idev->dev, "Missing adc-startup-time property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->startup_time = prop;
+
+
+	if (of_property_read_u32(node, "atmel,adc-vref", &prop)) {
+		dev_err(&idev->dev, "Missing adc-vref property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->vref_mv = prop;
+
+	st->registers = devm_kzalloc(&idev->dev,
+				     sizeof(struct at91_adc_reg_desc),
+				     GFP_KERNEL);
+	if (!st->registers) {
+		dev_err(&idev->dev, "Could not allocate register memory.\n");
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	if (of_property_read_u32(node, "atmel,adc-channel-base", &prop)) {
+		dev_err(&idev->dev, "Missing adc-channel-base property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->registers->channel_base = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-drdy-mask", &prop)) {
+		dev_err(&idev->dev, "Missing adc-drdy-mask property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->registers->drdy_mask = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-status-register", &prop)) {
+		dev_err(&idev->dev, "Missing adc-status-register property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->registers->status_register = prop;
+
+	if (of_property_read_u32(node, "atmel,adc-trigger-register", &prop)) {
+		dev_err(&idev->dev, "Missing adc-trigger-register property in the DT.\n");
+		ret = -EINVAL;
+		goto error_ret;
+	}
+	st->registers->trigger_register = prop;
+
+	st->trigger_number = of_get_child_count(node);
+	st->trigger_list = devm_kzalloc(&idev->dev, st->trigger_number *
+					sizeof(struct at91_adc_trigger),
+					GFP_KERNEL);
+	if (!st->trigger_list) {
+		dev_err(&idev->dev, "Could not allocate trigger list memory.\n");
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+
+	for_each_child_of_node(node, trig_node) {
+		struct at91_adc_trigger *trig = st->trigger_list + i;
+		const char *name;
+
+		if (of_property_read_string(trig_node, "trigger-name", &name)) {
+			dev_err(&idev->dev, "Missing trigger-name property in the DT.\n");
+			ret = -EINVAL;
+			goto error_ret;
+		}
+	        trig->name = name;
+
+		if (of_property_read_u32(trig_node, "trigger-value", &prop)) {
+			dev_err(&idev->dev, "Missing trigger-value property in the DT.\n");
+			ret = -EINVAL;
+			goto error_ret;
+		}
+	        trig->value = prop;
+		trig->is_external = of_property_read_bool(trig_node, "trigger-external");
+		i++;
+	}
+
+	return 0;
+
+error_ret:
+	return ret;
+}
+
 static int at91_adc_probe_pdata(struct at91_adc_state *st,
 				struct platform_device *pdev)
 {
@@ -456,7 +575,11 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
 
 	st = iio_priv(idev);
 
-	ret = at91_adc_probe_pdata(st, pdev);
+	if (pdev->dev.of_node)
+		ret = at91_adc_probe_dt(st, pdev);
+	else
+		ret = at91_adc_probe_pdata(st, pdev);
+
 	if (ret) {
 		dev_err(&pdev->dev, "No platform data available.\n");
 		ret = -EINVAL;
@@ -658,11 +781,18 @@ static int __devexit at91_adc_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static const struct of_device_id at91_adc_dt_ids[] = {
+	{ .compatible = "atmel,at91sam9260-adc" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, at91_adc_dt_ids);
+
 static struct platform_driver at91_adc_driver = {
 	.probe = at91_adc_probe,
 	.remove = __devexit_p(at91_adc_remove),
 	.driver = {
 		   .name = "at91_adc",
+		   .of_match_table = of_match_ptr(at91_adc_dt_ids),
 	},
 };
 
-- 
1.7.9.5

Re: [PATCH 6/9] IIO: AT91: Add DT support to at91_adc driver

[Jonathan Cameron]

All this is fine with me.  I'm far from expert at device tree though so
over to those that are :)

On 5/9/2012 2:02 PM, Maxime Ripard wrote:
> Signed-off-by: Maxime Ripard<maxime.ripard@free-electrons.com>
> Acked-by: Nicolas Ferre<nicolas.ferre@atmel.com>
> ---
>   .../devicetree/bindings/arm/atmel-adc.txt          |   65 ++++++++++
>   drivers/iio/adc/at91_adc.c                         |  132 +++++++++++++++++++-
>   2 files changed, 196 insertions(+), 1 deletion(-)
>   create mode 100644 Documentation/devicetree/bindings/arm/atmel-adc.txt
>
> diff --git a/Documentation/devicetree/bindings/arm/atmel-adc.txt b/Documentation/devicetree/bindings/arm/atmel-adc.txt
> new file mode 100644
> index 0000000..c63097d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/atmel-adc.txt
> @@ -0,0 +1,65 @@
> +* AT91's Analog to Digital Converter (ADC)
> +
> +Required properties:
> +  - compatible: Should be "atmel,at91sam9260-adc"
> +  - reg: Should contain ADC registers location and length
> +  - interrupts: Should contain the IRQ line for the ADC
> +  - atmel,adc-channel-base: Offset of the first channel data register
> +  - atmel,adc-channels-used: Bitmask of the channels muxed and enable for this
> +    device
> +  - atmel,adc-drdy-mask: Mask of the DRDY interruption in the ADC
> +  - atmel,adc-num-channels: Number of channels available in the ADC
> +  - atmel,adc-startup-time: Startup Time of the ADC in microseconds as
> +    defined in the datasheet
> +  - atmel,adc-status-register: Offset of the Interrupt Status Register
> +  - atmel,adc-trigger-register: Offset of the Trigger Register
> +  - atmel,adc-vref: Reference voltage in millivolts for the conversions
> +
> +Optional properties:
> +  - atmel,adc-use-external: Boolean to enable of external triggers
> +
> +Optional trigger Nodes:
> +  - Required properties:
> +    * trigger-name: Name of the trigger exposed to the user
> +    * trigger-value: Value to put in the Trigger register
> +      to activate this trigger
> +  - Optional properties:
> +    * trigger-external: Is the trigger an external trigger?
> +
> +Examples:
> +adc0: adc@fffb0000 {
> +	compatible = "atmel,at91sam9260-adc";
> +	reg =<0xfffb0000 0x100>;
> +	interrupts =<20 4>;
> +	atmel,adc-channel-base =<0x30>;
> +	atmel,adc-channels-used =<0xff>;
> +	atmel,adc-drdy-mask =<0x10000>;
> +	atmel,adc-num-channels =<8>;
> +	atmel,adc-startup-time =<40>;
> +	atmel,adc-status-register =<0x1c>;
> +	atmel,adc-trigger-register =<0x08>;
> +	atmel,adc-use-external;
> +	atmel,adc-vref =<3300>;
> +
> +	trigger@0 {
> +		trigger-name = "external-rising";
> +		trigger-value =<0x1>;
> +		trigger-external;
> +	};
> +	trigger@1 {
> +		trigger-name = "external-falling";
> +		trigger-value =<0x2>;
> +		trigger-external;
> +	};
> +
> +	trigger@2 {
> +		trigger-name = "external-any";
> +		trigger-value =<0x3>;
> +		trigger-external;
> +	};
> +
> +	trigger@3 {
> +		trigger-name = "continuous";
> +		trigger-value =<0x6>;
> +	};
> +};
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> index e5d73b1..d2eca64 100644
> --- a/drivers/iio/adc/at91_adc.c
> +++ b/drivers/iio/adc/at91_adc.c
> @@ -15,6 +15,8 @@
>   #include<linux/jiffies.h>
>   #include<linux/kernel.h>
>   #include<linux/module.h>
> +#include<linux/of.h>
> +#include<linux/of_device.h>
>   #include<linux/platform_device.h>
>   #include<linux/sched.h>
>   #include<linux/slab.h>
> @@ -415,6 +417,123 @@ static int at91_adc_read_raw(struct iio_dev *idev,
>   	return -EINVAL;
>   }
>
> +static int at91_adc_probe_dt(struct at91_adc_state *st,
> +			     struct platform_device *pdev)
> +{
> +	struct iio_dev *idev = iio_priv_to_dev(st);
> +	struct device_node *node = pdev->dev.of_node;
> +	struct device_node *trig_node;
> +	int i = 0, ret;
> +	u32 prop;
> +
> +	if (!node)
> +		return -EINVAL;
> +
> +	st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers");
> +
> +	if (of_property_read_u32(node, "atmel,adc-channels-used",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-channels-used property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->channels_mask = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-num-channels",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-num-channels property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->num_channels = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-startup-time",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-startup-time property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->startup_time = prop;
> +
> +
> +	if (of_property_read_u32(node, "atmel,adc-vref",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-vref property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->vref_mv = prop;
> +
> +	st->registers = devm_kzalloc(&idev->dev,
> +				     sizeof(struct at91_adc_reg_desc),
> +				     GFP_KERNEL);
> +	if (!st->registers) {
> +		dev_err(&idev->dev, "Could not allocate register memory.\n");
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	if (of_property_read_u32(node, "atmel,adc-channel-base",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-channel-base property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->registers->channel_base = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-drdy-mask",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-drdy-mask property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->registers->drdy_mask = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-status-register",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-status-register property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->registers->status_register = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-trigger-register",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-trigger-register property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->registers->trigger_register = prop;
> +
> +	st->trigger_number = of_get_child_count(node);
> +	st->trigger_list = devm_kzalloc(&idev->dev, st->trigger_number *
> +					sizeof(struct at91_adc_trigger),
> +					GFP_KERNEL);
> +	if (!st->trigger_list) {
> +		dev_err(&idev->dev, "Could not allocate trigger list memory.\n");
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	for_each_child_of_node(node, trig_node) {
> +		struct at91_adc_trigger *trig = st->trigger_list + i;
> +		const char *name;
> +
> +		if (of_property_read_string(trig_node, "trigger-name",&name)) {
> +			dev_err(&idev->dev, "Missing trigger-name property in the DT.\n");
> +			ret = -EINVAL;
> +			goto error_ret;
> +		}
> +	        trig->name = name;
> +
> +		if (of_property_read_u32(trig_node, "trigger-value",&prop)) {
> +			dev_err(&idev->dev, "Missing trigger-value property in the DT.\n");
> +			ret = -EINVAL;
> +			goto error_ret;
> +		}
> +	        trig->value = prop;
> +		trig->is_external = of_property_read_bool(trig_node, "trigger-external");
> +		i++;
> +	}
> +
> +	return 0;
> +
> +error_ret:
> +	return ret;
> +}
> +
>   static int at91_adc_probe_pdata(struct at91_adc_state *st,
>   				struct platform_device *pdev)
>   {
> @@ -456,7 +575,11 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
>
>   	st = iio_priv(idev);
>
> -	ret = at91_adc_probe_pdata(st, pdev);
> +	if (pdev->dev.of_node)
> +		ret = at91_adc_probe_dt(st, pdev);
> +	else
> +		ret = at91_adc_probe_pdata(st, pdev);
> +
>   	if (ret) {
>   		dev_err(&pdev->dev, "No platform data available.\n");
>   		ret = -EINVAL;
> @@ -658,11 +781,18 @@ static int __devexit at91_adc_remove(struct platform_device *pdev)
>   	return 0;
>   }
>
> +static const struct of_device_id at91_adc_dt_ids[] = {
> +	{ .compatible = "atmel,at91sam9260-adc" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, at91_adc_dt_ids);
> +
>   static struct platform_driver at91_adc_driver = {
>   	.probe = at91_adc_probe,
>   	.remove = __devexit_p(at91_adc_remove),
>   	.driver = {
>   		   .name = "at91_adc",
> +		   .of_match_table = of_match_ptr(at91_adc_dt_ids),
>   	},
>   };
>

[PATCH 6/9] IIO: AT91: Add DT support to at91_adc driver

[Jonathan Cameron]

All this is fine with me.  I'm far from expert at device tree though so
over to those that are :)

On 5/9/2012 2:02 PM, Maxime Ripard wrote:
> Signed-off-by: Maxime Ripard<maxime.ripard@free-electrons.com>
> Acked-by: Nicolas Ferre<nicolas.ferre@atmel.com>
> ---
>   .../devicetree/bindings/arm/atmel-adc.txt          |   65 ++++++++++
>   drivers/iio/adc/at91_adc.c                         |  132 +++++++++++++++++++-
>   2 files changed, 196 insertions(+), 1 deletion(-)
>   create mode 100644 Documentation/devicetree/bindings/arm/atmel-adc.txt
>
> diff --git a/Documentation/devicetree/bindings/arm/atmel-adc.txt b/Documentation/devicetree/bindings/arm/atmel-adc.txt
> new file mode 100644
> index 0000000..c63097d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/atmel-adc.txt
> @@ -0,0 +1,65 @@
> +* AT91's Analog to Digital Converter (ADC)
> +
> +Required properties:
> +  - compatible: Should be "atmel,at91sam9260-adc"
> +  - reg: Should contain ADC registers location and length
> +  - interrupts: Should contain the IRQ line for the ADC
> +  - atmel,adc-channel-base: Offset of the first channel data register
> +  - atmel,adc-channels-used: Bitmask of the channels muxed and enable for this
> +    device
> +  - atmel,adc-drdy-mask: Mask of the DRDY interruption in the ADC
> +  - atmel,adc-num-channels: Number of channels available in the ADC
> +  - atmel,adc-startup-time: Startup Time of the ADC in microseconds as
> +    defined in the datasheet
> +  - atmel,adc-status-register: Offset of the Interrupt Status Register
> +  - atmel,adc-trigger-register: Offset of the Trigger Register
> +  - atmel,adc-vref: Reference voltage in millivolts for the conversions
> +
> +Optional properties:
> +  - atmel,adc-use-external: Boolean to enable of external triggers
> +
> +Optional trigger Nodes:
> +  - Required properties:
> +    * trigger-name: Name of the trigger exposed to the user
> +    * trigger-value: Value to put in the Trigger register
> +      to activate this trigger
> +  - Optional properties:
> +    * trigger-external: Is the trigger an external trigger?
> +
> +Examples:
> +adc0: adc at fffb0000 {
> +	compatible = "atmel,at91sam9260-adc";
> +	reg =<0xfffb0000 0x100>;
> +	interrupts =<20 4>;
> +	atmel,adc-channel-base =<0x30>;
> +	atmel,adc-channels-used =<0xff>;
> +	atmel,adc-drdy-mask =<0x10000>;
> +	atmel,adc-num-channels =<8>;
> +	atmel,adc-startup-time =<40>;
> +	atmel,adc-status-register =<0x1c>;
> +	atmel,adc-trigger-register =<0x08>;
> +	atmel,adc-use-external;
> +	atmel,adc-vref =<3300>;
> +
> +	trigger at 0 {
> +		trigger-name = "external-rising";
> +		trigger-value =<0x1>;
> +		trigger-external;
> +	};
> +	trigger at 1 {
> +		trigger-name = "external-falling";
> +		trigger-value =<0x2>;
> +		trigger-external;
> +	};
> +
> +	trigger at 2 {
> +		trigger-name = "external-any";
> +		trigger-value =<0x3>;
> +		trigger-external;
> +	};
> +
> +	trigger at 3 {
> +		trigger-name = "continuous";
> +		trigger-value =<0x6>;
> +	};
> +};
> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
> index e5d73b1..d2eca64 100644
> --- a/drivers/iio/adc/at91_adc.c
> +++ b/drivers/iio/adc/at91_adc.c
> @@ -15,6 +15,8 @@
>   #include<linux/jiffies.h>
>   #include<linux/kernel.h>
>   #include<linux/module.h>
> +#include<linux/of.h>
> +#include<linux/of_device.h>
>   #include<linux/platform_device.h>
>   #include<linux/sched.h>
>   #include<linux/slab.h>
> @@ -415,6 +417,123 @@ static int at91_adc_read_raw(struct iio_dev *idev,
>   	return -EINVAL;
>   }
>
> +static int at91_adc_probe_dt(struct at91_adc_state *st,
> +			     struct platform_device *pdev)
> +{
> +	struct iio_dev *idev = iio_priv_to_dev(st);
> +	struct device_node *node = pdev->dev.of_node;
> +	struct device_node *trig_node;
> +	int i = 0, ret;
> +	u32 prop;
> +
> +	if (!node)
> +		return -EINVAL;
> +
> +	st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers");
> +
> +	if (of_property_read_u32(node, "atmel,adc-channels-used",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-channels-used property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->channels_mask = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-num-channels",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-num-channels property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->num_channels = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-startup-time",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-startup-time property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->startup_time = prop;
> +
> +
> +	if (of_property_read_u32(node, "atmel,adc-vref",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-vref property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->vref_mv = prop;
> +
> +	st->registers = devm_kzalloc(&idev->dev,
> +				     sizeof(struct at91_adc_reg_desc),
> +				     GFP_KERNEL);
> +	if (!st->registers) {
> +		dev_err(&idev->dev, "Could not allocate register memory.\n");
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	if (of_property_read_u32(node, "atmel,adc-channel-base",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-channel-base property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->registers->channel_base = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-drdy-mask",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-drdy-mask property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->registers->drdy_mask = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-status-register",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-status-register property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->registers->status_register = prop;
> +
> +	if (of_property_read_u32(node, "atmel,adc-trigger-register",&prop)) {
> +		dev_err(&idev->dev, "Missing adc-trigger-register property in the DT.\n");
> +		ret = -EINVAL;
> +		goto error_ret;
> +	}
> +	st->registers->trigger_register = prop;
> +
> +	st->trigger_number = of_get_child_count(node);
> +	st->trigger_list = devm_kzalloc(&idev->dev, st->trigger_number *
> +					sizeof(struct at91_adc_trigger),
> +					GFP_KERNEL);
> +	if (!st->trigger_list) {
> +		dev_err(&idev->dev, "Could not allocate trigger list memory.\n");
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +
> +	for_each_child_of_node(node, trig_node) {
> +		struct at91_adc_trigger *trig = st->trigger_list + i;
> +		const char *name;
> +
> +		if (of_property_read_string(trig_node, "trigger-name",&name)) {
> +			dev_err(&idev->dev, "Missing trigger-name property in the DT.\n");
> +			ret = -EINVAL;
> +			goto error_ret;
> +		}
> +	        trig->name = name;
> +
> +		if (of_property_read_u32(trig_node, "trigger-value",&prop)) {
> +			dev_err(&idev->dev, "Missing trigger-value property in the DT.\n");
> +			ret = -EINVAL;
> +			goto error_ret;
> +		}
> +	        trig->value = prop;
> +		trig->is_external = of_property_read_bool(trig_node, "trigger-external");
> +		i++;
> +	}
> +
> +	return 0;
> +
> +error_ret:
> +	return ret;
> +}
> +
>   static int at91_adc_probe_pdata(struct at91_adc_state *st,
>   				struct platform_device *pdev)
>   {
> @@ -456,7 +575,11 @@ static int __devinit at91_adc_probe(struct platform_device *pdev)
>
>   	st = iio_priv(idev);
>
> -	ret = at91_adc_probe_pdata(st, pdev);
> +	if (pdev->dev.of_node)
> +		ret = at91_adc_probe_dt(st, pdev);
> +	else
> +		ret = at91_adc_probe_pdata(st, pdev);
> +
>   	if (ret) {
>   		dev_err(&pdev->dev, "No platform data available.\n");
>   		ret = -EINVAL;
> @@ -658,11 +781,18 @@ static int __devexit at91_adc_remove(struct platform_device *pdev)
>   	return 0;
>   }
>
> +static const struct of_device_id at91_adc_dt_ids[] = {
> +	{ .compatible = "atmel,at91sam9260-adc" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, at91_adc_dt_ids);
> +
>   static struct platform_driver at91_adc_driver = {
>   	.probe = at91_adc_probe,
>   	.remove = __devexit_p(at91_adc_remove),
>   	.driver = {
>   		   .name = "at91_adc",
> +		   .of_match_table = of_match_ptr(at91_adc_dt_ids),
>   	},
>   };
>

[PATCH 7/9] ARM: AT91: Add ADC driver to the at91sam9g45 dtsi

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/boot/dts/at91sam9g45.dtsi |   37 ++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/arch/arm/boot/dts/at91sam9g45.dtsi b/arch/arm/boot/dts/at91sam9g45.dtsi
index c804214..7dbccaf 100644
--- a/arch/arm/boot/dts/at91sam9g45.dtsi
+++ b/arch/arm/boot/dts/at91sam9g45.dtsi
@@ -199,6 +199,43 @@
 				interrupts = <25 4>;
 				status = "disabled";
 			};
+
+			adc0: adc@fffb0000 {
+				compatible = "atmel,at91sam9260-adc";
+				reg = <0xfffb0000 0x100>;
+				interrupts = <20 4>;
+				atmel,adc-use-external-triggers;
+				atmel,adc-channels-used = <0xff>;
+				atmel,adc-vref = <3300>;
+				atmel,adc-num-channels = <8>;
+				atmel,adc-startup-time = <40>;
+				atmel,adc-channel-base = <0x30>;
+				atmel,adc-drdy-mask = <0x10000>;
+				atmel,adc-status-register = <0x1c>;
+				atmel,adc-trigger-register = <0x08>;
+
+				trigger@0 {
+					trigger-name = "external-rising";
+					trigger-value = <0x1>;
+					trigger-external;
+				};
+				trigger@1 {
+					trigger-name = "external-falling";
+					trigger-value = <0x2>;
+					trigger-external;
+				};
+
+				trigger@2 {
+					trigger-name = "external-any";
+					trigger-value = <0x3>;
+					trigger-external;
+				};
+
+				trigger@3 {
+					trigger-name = "continuous";
+					trigger-value = <0x6>;
+				};
+			};
 		};
 
 		nand0: nand@40000000 {
-- 
1.7.9.5

[PATCH 7/9] ARM: AT91: Add ADC driver to the at91sam9g45 dtsi

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/boot/dts/at91sam9g45.dtsi |   37 ++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/arch/arm/boot/dts/at91sam9g45.dtsi b/arch/arm/boot/dts/at91sam9g45.dtsi
index c804214..7dbccaf 100644
--- a/arch/arm/boot/dts/at91sam9g45.dtsi
+++ b/arch/arm/boot/dts/at91sam9g45.dtsi
@@ -199,6 +199,43 @@
 				interrupts = <25 4>;
 				status = "disabled";
 			};
+
+			adc0: adc at fffb0000 {
+				compatible = "atmel,at91sam9260-adc";
+				reg = <0xfffb0000 0x100>;
+				interrupts = <20 4>;
+				atmel,adc-use-external-triggers;
+				atmel,adc-channels-used = <0xff>;
+				atmel,adc-vref = <3300>;
+				atmel,adc-num-channels = <8>;
+				atmel,adc-startup-time = <40>;
+				atmel,adc-channel-base = <0x30>;
+				atmel,adc-drdy-mask = <0x10000>;
+				atmel,adc-status-register = <0x1c>;
+				atmel,adc-trigger-register = <0x08>;
+
+				trigger at 0 {
+					trigger-name = "external-rising";
+					trigger-value = <0x1>;
+					trigger-external;
+				};
+				trigger at 1 {
+					trigger-name = "external-falling";
+					trigger-value = <0x2>;
+					trigger-external;
+				};
+
+				trigger at 2 {
+					trigger-name = "external-any";
+					trigger-value = <0x3>;
+					trigger-external;
+				};
+
+				trigger at 3 {
+					trigger-name = "continuous";
+					trigger-value = <0x6>;
+				};
+			};
 		};
 
 		nand0: nand at 40000000 {
-- 
1.7.9.5

[PATCH 8/9] ARM: AT91: Add ADC driver to the at91sam9x5 dtsi

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/boot/dts/at91sam9x5.dtsi |   38 +++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi b/arch/arm/boot/dts/at91sam9x5.dtsi
index dd4ed74..6b3ef43 100644
--- a/arch/arm/boot/dts/at91sam9x5.dtsi
+++ b/arch/arm/boot/dts/at91sam9x5.dtsi
@@ -190,6 +190,44 @@
 				interrupts = <27 4>;
 				status = "disabled";
 			};
+
+			adc0: adc@f804c000 {
+				compatible = "atmel,at91sam9260-adc";
+				reg = <0xf804c000 0x100>;
+				interrupts = <19 4>;
+				atmel,adc-use-external;
+				atmel,adc-channels-used = <0xffff>;
+				atmel,adc-vref = <3300>;
+				atmel,adc-num-channels = <12>;
+				atmel,adc-startup-time = <40>;
+				atmel,adc-channel-base = <0x50>;
+				atmel,adc-drdy-mask = <0x1000000>;
+				atmel,adc-status-register = <0x30>;
+				atmel,adc-trigger-register = <0xc0>;
+
+				trigger@0 {
+					trigger-name = "external-rising";
+					trigger-value = <0x1>;
+					trigger-external;
+				};
+
+				trigger@1 {
+					trigger-name = "external-falling";
+					trigger-value = <0x2>;
+					trigger-external;
+				};
+
+				trigger@2 {
+					trigger-name = "external-any";
+					trigger-value = <0x3>;
+					trigger-external;
+				};
+
+				trigger@3 {
+					trigger-name = "continuous";
+					trigger-value = <0x6>;
+				};
+			};
 		};
 
 		nand0: nand@40000000 {
-- 
1.7.9.5

[PATCH 8/9] ARM: AT91: Add ADC driver to the at91sam9x5 dtsi

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/boot/dts/at91sam9x5.dtsi |   38 +++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/arch/arm/boot/dts/at91sam9x5.dtsi b/arch/arm/boot/dts/at91sam9x5.dtsi
index dd4ed74..6b3ef43 100644
--- a/arch/arm/boot/dts/at91sam9x5.dtsi
+++ b/arch/arm/boot/dts/at91sam9x5.dtsi
@@ -190,6 +190,44 @@
 				interrupts = <27 4>;
 				status = "disabled";
 			};
+
+			adc0: adc at f804c000 {
+				compatible = "atmel,at91sam9260-adc";
+				reg = <0xf804c000 0x100>;
+				interrupts = <19 4>;
+				atmel,adc-use-external;
+				atmel,adc-channels-used = <0xffff>;
+				atmel,adc-vref = <3300>;
+				atmel,adc-num-channels = <12>;
+				atmel,adc-startup-time = <40>;
+				atmel,adc-channel-base = <0x50>;
+				atmel,adc-drdy-mask = <0x1000000>;
+				atmel,adc-status-register = <0x30>;
+				atmel,adc-trigger-register = <0xc0>;
+
+				trigger at 0 {
+					trigger-name = "external-rising";
+					trigger-value = <0x1>;
+					trigger-external;
+				};
+
+				trigger at 1 {
+					trigger-name = "external-falling";
+					trigger-value = <0x2>;
+					trigger-external;
+				};
+
+				trigger at 2 {
+					trigger-name = "external-any";
+					trigger-value = <0x3>;
+					trigger-external;
+				};
+
+				trigger at 3 {
+					trigger-name = "continuous";
+					trigger-value = <0x6>;
+				};
+			};
 		};
 
 		nand0: nand at 40000000 {
-- 
1.7.9.5

[PATCH 9/9] ARM: AT91: Add ADC driver to the at91sam9g20 dtsi

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/boot/dts/at91sam9g20.dtsi |   35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/arch/arm/boot/dts/at91sam9g20.dtsi b/arch/arm/boot/dts/at91sam9g20.dtsi
index 773ef48..767764c 100644
--- a/arch/arm/boot/dts/at91sam9g20.dtsi
+++ b/arch/arm/boot/dts/at91sam9g20.dtsi
@@ -197,6 +197,41 @@
 				interrupts = <10 4>;
 				status = "disabled";
 			};
+
+			adc0: adc@fffe0000 {
+				compatible = "atmel,at91sam9260-adc";
+				reg = <0xfffe0000 0x100>;
+				interrupts = <5 4>;
+				atmel,adc-use-external-triggers;
+				atmel,adc-channels-used = <0xf>;
+				atmel,adc-vref = <3300>;
+				atmel,adc-num-channels = <4>;
+				atmel,adc-startup-time = <10>;
+				atmel,adc-channel-base = <0x30>;
+				atmel,adc-drdy-mask = <0x10000>;
+				atmel,adc-status-register = <0x1c>;
+				atmel,adc-trigger-register = <0x04>;
+
+				trigger@0 {
+					trigger-name = "timer-counter-0";
+					trigger-value = <0x1>;
+				};
+				trigger@1 {
+					trigger-name = "timer-counter-1";
+					trigger-value = <0x3>;
+				};
+
+				trigger@2 {
+					trigger-name = "timer-counter-2";
+					trigger-value = <0x5>;
+				};
+
+				trigger@3 {
+					trigger-name = "external";
+					trigger-value = <0x13>;
+					trigger-external;
+				};
+			};
 		};
 
 		nand0: nand@40000000 {
-- 
1.7.9.5

[PATCH 9/9] ARM: AT91: Add ADC driver to the at91sam9g20 dtsi

[Maxime Ripard]

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/boot/dts/at91sam9g20.dtsi |   35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/arch/arm/boot/dts/at91sam9g20.dtsi b/arch/arm/boot/dts/at91sam9g20.dtsi
index 773ef48..767764c 100644
--- a/arch/arm/boot/dts/at91sam9g20.dtsi
+++ b/arch/arm/boot/dts/at91sam9g20.dtsi
@@ -197,6 +197,41 @@
 				interrupts = <10 4>;
 				status = "disabled";
 			};
+
+			adc0: adc at fffe0000 {
+				compatible = "atmel,at91sam9260-adc";
+				reg = <0xfffe0000 0x100>;
+				interrupts = <5 4>;
+				atmel,adc-use-external-triggers;
+				atmel,adc-channels-used = <0xf>;
+				atmel,adc-vref = <3300>;
+				atmel,adc-num-channels = <4>;
+				atmel,adc-startup-time = <10>;
+				atmel,adc-channel-base = <0x30>;
+				atmel,adc-drdy-mask = <0x10000>;
+				atmel,adc-status-register = <0x1c>;
+				atmel,adc-trigger-register = <0x04>;
+
+				trigger at 0 {
+					trigger-name = "timer-counter-0";
+					trigger-value = <0x1>;
+				};
+				trigger at 1 {
+					trigger-name = "timer-counter-1";
+					trigger-value = <0x3>;
+				};
+
+				trigger at 2 {
+					trigger-name = "timer-counter-2";
+					trigger-value = <0x5>;
+				};
+
+				trigger at 3 {
+					trigger-name = "external";
+					trigger-value = <0x13>;
+					trigger-external;
+				};
+			};
 		};
 
 		nand0: nand at 40000000 {
-- 
1.7.9.5

[PATCHv5] Add ADC driver for Atmel G20, G45 and X5 boards

[Maxime Ripard]

Hi Greg,

Here is a patchset adding an IIO driver for various Atmel SoCs.
As it relies on out-of-staging-IIO, which is still in staging-next, it
seems that you should be the one merging it.

As you can see, it got an acked-by all the maintainers involved in this
patch, so it should be pretty good for inclusion.

Thanks,
Maxime

[PATCH 1/9] ARM: AT91: Add platform data for the AT91 ADCs

[Maxime Ripard]

The AT91 SoCs often embeds an ADC. This patch adds the needed
platform data to specify the informations required by the driver
to work properly.

For now, we only need the reference voltage and which channels
are available on the board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
---
 include/linux/platform_data/at91_adc.h |   61 ++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 include/linux/platform_data/at91_adc.h

diff --git a/include/linux/platform_data/at91_adc.h b/include/linux/platform_data/at91_adc.h
new file mode 100644
index 0000000..e15745b
--- /dev/null
+++ b/include/linux/platform_data/at91_adc.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2011 Free Electrons
+ *
+ * Licensed under the GPLv2 or later.
+ */
+
+#ifndef _AT91_ADC_H_
+#define _AT91_ADC_H_
+
+/**
+ * struct at91_adc_reg_desc - Various informations relative to registers
+ * @channel_base:	Base offset for the channel data registers
+ * @drdy_mask:		Mask of the DRDY field in the relevant registers
+			(Interruptions registers mostly)
+ * @status_register:	Offset of the Interrupt Status Register
+ * @trigger_register:	Offset of the Trigger setup register
+ */
+struct at91_adc_reg_desc {
+	u8	channel_base;
+	u32	drdy_mask;
+	u8	status_register;
+	u8	trigger_register;
+};
+
+/**
+ * struct at91_adc_trigger - description of triggers
+ * @name:		name of the trigger advertised to the user
+ * @value:		value to set in the ADC's trigger setup register
+			to enable the trigger
+ * @is_external:	Does the trigger rely on an external pin?
+ */
+struct at91_adc_trigger {
+	const char	*name;
+	u8		value;
+	bool		is_external;
+};
+
+/**
+ * struct at91_adc_data - platform data for ADC driver
+ * @channels_used:		channels in use on the board as a bitmask
+ * @num_channels:		global number of channels available on the board
+ * @registers:			Registers definition on the board
+ * @startup_time:		startup time of the ADC in microseconds
+ * @trigger_list:		Triggers available in the ADC
+ * @trigger_number:		Number of triggers available in the ADC
+ * @use_external_triggers:	does the board has external triggers availables
+ * @vref:			Reference voltage for the ADC in millivolts
+ */
+struct at91_adc_data {
+	unsigned long			channels_used;
+	u8				num_channels;
+	struct at91_adc_reg_desc	*registers;
+	u8				startup_time;
+	struct at91_adc_trigger		*trigger_list;
+	u8				trigger_number;
+	bool				use_external_triggers;
+	u16				vref;
+};
+
+extern void __init at91_add_device_adc(struct at91_adc_data *data);
+#endif
-- 
1.7.9.5

[PATCH 1/9] ARM: AT91: Add platform data for the AT91 ADCs

[Maxime Ripard]

The AT91 SoCs often embeds an ADC. This patch adds the needed
platform data to specify the informations required by the driver
to work properly.

For now, we only need the reference voltage and which channels
are available on the board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
---
 include/linux/platform_data/at91_adc.h |   61 ++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 include/linux/platform_data/at91_adc.h

diff --git a/include/linux/platform_data/at91_adc.h b/include/linux/platform_data/at91_adc.h
new file mode 100644
index 0000000..e15745b
--- /dev/null
+++ b/include/linux/platform_data/at91_adc.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2011 Free Electrons
+ *
+ * Licensed under the GPLv2 or later.
+ */
+
+#ifndef _AT91_ADC_H_
+#define _AT91_ADC_H_
+
+/**
+ * struct at91_adc_reg_desc - Various informations relative to registers
+ * @channel_base:	Base offset for the channel data registers
+ * @drdy_mask:		Mask of the DRDY field in the relevant registers
+			(Interruptions registers mostly)
+ * @status_register:	Offset of the Interrupt Status Register
+ * @trigger_register:	Offset of the Trigger setup register
+ */
+struct at91_adc_reg_desc {
+	u8	channel_base;
+	u32	drdy_mask;
+	u8	status_register;
+	u8	trigger_register;
+};
+
+/**
+ * struct at91_adc_trigger - description of triggers
+ * @name:		name of the trigger advertised to the user
+ * @value:		value to set in the ADC's trigger setup register
+			to enable the trigger
+ * @is_external:	Does the trigger rely on an external pin?
+ */
+struct at91_adc_trigger {
+	const char	*name;
+	u8		value;
+	bool		is_external;
+};
+
+/**
+ * struct at91_adc_data - platform data for ADC driver
+ * @channels_used:		channels in use on the board as a bitmask
+ * @num_channels:		global number of channels available on the board
+ * @registers:			Registers definition on the board
+ * @startup_time:		startup time of the ADC in microseconds
+ * @trigger_list:		Triggers available in the ADC
+ * @trigger_number:		Number of triggers available in the ADC
+ * @use_external_triggers:	does the board has external triggers availables
+ * @vref:			Reference voltage for the ADC in millivolts
+ */
+struct at91_adc_data {
+	unsigned long			channels_used;
+	u8				num_channels;
+	struct at91_adc_reg_desc	*registers;
+	u8				startup_time;
+	struct at91_adc_trigger		*trigger_list;
+	u8				trigger_number;
+	bool				use_external_triggers;
+	u16				vref;
+};
+
+extern void __init at91_add_device_adc(struct at91_adc_data *data);
+#endif
-- 
1.7.9.5

[PATCHv3] Add ADC driver for Atmel G20, G45 and X5 boards

[Maxime Ripard]

Hi all,

Here is another version of the patches to bring ADC driver to Atmel boards.
Since last version, here is what changed:
  * Rebased on top of staging-next to move out of staging. Had to change to IIO
    kfifo buffer along the way.
  * Reworked the DT bindings according to Jean-Christophe reviews
  * Made various fixes according to reviews
  * Support for X5 boards

Thanks,
Maxime

[PATCH 1/9] ARM: AT91: Add platform data for the AT91 ADCs

[Maxime Ripard]

The AT91 SoCs often embeds an ADC. This patch adds the needed
platform data to specify the informations required by the driver
to work properly.

For now, we only need the reference voltage and which channels
are available on the board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
 include/linux/platform_data/at91_adc.h |   61 ++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 include/linux/platform_data/at91_adc.h

diff --git a/include/linux/platform_data/at91_adc.h b/include/linux/platform_data/at91_adc.h
new file mode 100644
index 0000000..f9e2f00
--- /dev/null
+++ b/include/linux/platform_data/at91_adc.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2011 Free Electrons
+ *
+ * Licensed under the GPLv2 or later.
+ */
+
+#ifndef _AT91_ADC_H_
+#define _AT91_ADC_H_
+
+/**
+ * struct at91_adc_reg_desc - Various informations relative to registers
+ * @channel_base:	Base address for the channel data registers
+ * @drdy_mask:		Mask of the DRDY field in the relevant registers
+			(Interruptions registers mostly)
+ * @status_register:	Address of the Interrupt Status Register
+ * @trigger_register:	Address of the Trigger setup register
+ */
+struct at91_adc_reg_desc {
+	u8	channel_base;
+	u32	drdy_mask;
+	u8	status_register;
+	u8	trigger_register;
+};
+
+/**
+ * struct at91_adc_trigger - description of triggers
+ * @name:		name of the trigger advertised to the user
+ * @value:		value to set in the ADC's mode register to enable
+			the trigger
+ * @is_external:	is the trigger relies on an external pin ?
+ */
+struct at91_adc_trigger {
+	const char	*name;
+	u8		value;
+	bool		is_external;
+};
+
+/**
+ * struct at91_adc_data - platform data for ADC driver
+ * @channels_used:		channels in use on the board as a bitmask
+ * @num_channels:		global number of channels available on the board
+ * @registers:			Registers definition on the board
+ * @startup_time:		startup time of the ADC in microseconds
+ * @trigger_list:		Triggers available in the ADC
+ * @trigger_number:		Number of triggers available in the ADC
+ * @use_external_triggers:	does the board has external triggers availables
+ * @vref:			Reference voltage for the ADC in millivolts
+ */
+struct at91_adc_data {
+	unsigned long			channels_used;
+	u8				num_channels;
+	struct at91_adc_reg_desc	*registers;
+	u8				startup_time;
+	struct at91_adc_trigger		*trigger_list;
+	u8				trigger_number;
+	bool				use_external_triggers;
+	u16				vref;
+};
+
+extern void __init at91_add_device_adc(struct at91_adc_data *data);
+#endif
-- 
1.7.9.5

[PATCH 1/9] ARM: AT91: Add platform data for the AT91 ADCs

[Maxime Ripard]

The AT91 SoCs often embeds an ADC. This patch adds the needed
platform data to specify the informations required by the driver
to work properly.

For now, we only need the reference voltage and which channels
are available on the board.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
 include/linux/platform_data/at91_adc.h |   61 ++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 include/linux/platform_data/at91_adc.h

diff --git a/include/linux/platform_data/at91_adc.h b/include/linux/platform_data/at91_adc.h
new file mode 100644
index 0000000..f9e2f00
--- /dev/null
+++ b/include/linux/platform_data/at91_adc.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2011 Free Electrons
+ *
+ * Licensed under the GPLv2 or later.
+ */
+
+#ifndef _AT91_ADC_H_
+#define _AT91_ADC_H_
+
+/**
+ * struct at91_adc_reg_desc - Various informations relative to registers
+ * @channel_base:	Base address for the channel data registers
+ * @drdy_mask:		Mask of the DRDY field in the relevant registers
+			(Interruptions registers mostly)
+ * @status_register:	Address of the Interrupt Status Register
+ * @trigger_register:	Address of the Trigger setup register
+ */
+struct at91_adc_reg_desc {
+	u8	channel_base;
+	u32	drdy_mask;
+	u8	status_register;
+	u8	trigger_register;
+};
+
+/**
+ * struct at91_adc_trigger - description of triggers
+ * @name:		name of the trigger advertised to the user
+ * @value:		value to set in the ADC's mode register to enable
+			the trigger
+ * @is_external:	is the trigger relies on an external pin ?
+ */
+struct at91_adc_trigger {
+	const char	*name;
+	u8		value;
+	bool		is_external;
+};
+
+/**
+ * struct at91_adc_data - platform data for ADC driver
+ * @channels_used:		channels in use on the board as a bitmask
+ * @num_channels:		global number of channels available on the board
+ * @registers:			Registers definition on the board
+ * @startup_time:		startup time of the ADC in microseconds
+ * @trigger_list:		Triggers available in the ADC
+ * @trigger_number:		Number of triggers available in the ADC
+ * @use_external_triggers:	does the board has external triggers availables
+ * @vref:			Reference voltage for the ADC in millivolts
+ */
+struct at91_adc_data {
+	unsigned long			channels_used;
+	u8				num_channels;
+	struct at91_adc_reg_desc	*registers;
+	u8				startup_time;
+	struct at91_adc_trigger		*trigger_list;
+	u8				trigger_number;
+	bool				use_external_triggers;
+	u16				vref;
+};
+
+extern void __init at91_add_device_adc(struct at91_adc_data *data);
+#endif
-- 
1.7.9.5

Re: [PATCH 1/9] ARM: AT91: Add platform data for the AT91 ADCs

[Jonathan Cameron]

On 5/9/2012 10:05 AM, Maxime Ripard wrote:
> The AT91 SoCs often embeds an ADC. This patch adds the needed
> platform data to specify the informations required by the driver
> to work properly.
>
> For now, we only need the reference voltage and which channels
> are available on the board.
One utterly trivial element inline.
> Signed-off-by: Maxime Ripard<maxime.ripard@free-electrons.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
>   include/linux/platform_data/at91_adc.h |   61 ++++++++++++++++++++++++++++++++
>   1 file changed, 61 insertions(+)
>   create mode 100644 include/linux/platform_data/at91_adc.h
>
> diff --git a/include/linux/platform_data/at91_adc.h b/include/linux/platform_data/at91_adc.h
> new file mode 100644
> index 0000000..f9e2f00
> --- /dev/null
> +++ b/include/linux/platform_data/at91_adc.h
> @@ -0,0 +1,61 @@
> +/*
> + * Copyright (C) 2011 Free Electrons
> + *
> + * Licensed under the GPLv2 or later.
> + */
> +
> +#ifndef _AT91_ADC_H_
> +#define _AT91_ADC_H_
> +
> +/**
> + * struct at91_adc_reg_desc - Various informations relative to registers
> + * @channel_base:	Base address for the channel data registers
> + * @drdy_mask:		Mask of the DRDY field in the relevant registers
> +			(Interruptions registers mostly)
> + * @status_register:	Address of the Interrupt Status Register
> + * @trigger_register:	Address of the Trigger setup register
> + */
> +struct at91_adc_reg_desc {
> +	u8	channel_base;
> +	u32	drdy_mask;
> +	u8	status_register;
> +	u8	trigger_register;
> +};
> +
> +/**
> + * struct at91_adc_trigger - description of triggers
> + * @name:		name of the trigger advertised to the user
> + * @value:		value to set in the ADC's mode register to enable
> +			the trigger
> + * @is_external:	is the trigger relies on an external pin ?
no space before the ? (nitpick of the day ;)
> + */
> +struct at91_adc_trigger {
> +	const char	*name;
> +	u8		value;
> +	bool		is_external;
> +};
> +
> +/**
> + * struct at91_adc_data - platform data for ADC driver
> + * @channels_used:		channels in use on the board as a bitmask
> + * @num_channels:		global number of channels available on the board
> + * @registers:			Registers definition on the board
> + * @startup_time:		startup time of the ADC in microseconds
> + * @trigger_list:		Triggers available in the ADC
> + * @trigger_number:		Number of triggers available in the ADC
> + * @use_external_triggers:	does the board has external triggers availables
> + * @vref:			Reference voltage for the ADC in millivolts
> + */
> +struct at91_adc_data {
> +	unsigned long			channels_used;
> +	u8				num_channels;
> +	struct at91_adc_reg_desc	*registers;
> +	u8				startup_time;
> +	struct at91_adc_trigger		*trigger_list;
> +	u8				trigger_number;
> +	bool				use_external_triggers;
> +	u16				vref;
> +};
> +
> +extern void __init at91_add_device_adc(struct at91_adc_data *data);
> +#endif

[PATCH 1/9] ARM: AT91: Add platform data for the AT91 ADCs

[Jonathan Cameron]

On 5/9/2012 10:05 AM, Maxime Ripard wrote:
> The AT91 SoCs often embeds an ADC. This patch adds the needed
> platform data to specify the informations required by the driver
> to work properly.
>
> For now, we only need the reference voltage and which channels
> are available on the board.
One utterly trivial element inline.
> Signed-off-by: Maxime Ripard<maxime.ripard@free-electrons.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
>   include/linux/platform_data/at91_adc.h |   61 ++++++++++++++++++++++++++++++++
>   1 file changed, 61 insertions(+)
>   create mode 100644 include/linux/platform_data/at91_adc.h
>
> diff --git a/include/linux/platform_data/at91_adc.h b/include/linux/platform_data/at91_adc.h
> new file mode 100644
> index 0000000..f9e2f00
> --- /dev/null
> +++ b/include/linux/platform_data/at91_adc.h
> @@ -0,0 +1,61 @@
> +/*
> + * Copyright (C) 2011 Free Electrons
> + *
> + * Licensed under the GPLv2 or later.
> + */
> +
> +#ifndef _AT91_ADC_H_
> +#define _AT91_ADC_H_
> +
> +/**
> + * struct at91_adc_reg_desc - Various informations relative to registers
> + * @channel_base:	Base address for the channel data registers
> + * @drdy_mask:		Mask of the DRDY field in the relevant registers
> +			(Interruptions registers mostly)
> + * @status_register:	Address of the Interrupt Status Register
> + * @trigger_register:	Address of the Trigger setup register
> + */
> +struct at91_adc_reg_desc {
> +	u8	channel_base;
> +	u32	drdy_mask;
> +	u8	status_register;
> +	u8	trigger_register;
> +};
> +
> +/**
> + * struct at91_adc_trigger - description of triggers
> + * @name:		name of the trigger advertised to the user
> + * @value:		value to set in the ADC's mode register to enable
> +			the trigger
> + * @is_external:	is the trigger relies on an external pin ?
no space before the ? (nitpick of the day ;)
> + */
> +struct at91_adc_trigger {
> +	const char	*name;
> +	u8		value;
> +	bool		is_external;
> +};
> +
> +/**
> + * struct at91_adc_data - platform data for ADC driver
> + * @channels_used:		channels in use on the board as a bitmask
> + * @num_channels:		global number of channels available on the board
> + * @registers:			Registers definition on the board
> + * @startup_time:		startup time of the ADC in microseconds
> + * @trigger_list:		Triggers available in the ADC
> + * @trigger_number:		Number of triggers available in the ADC
> + * @use_external_triggers:	does the board has external triggers availables
> + * @vref:			Reference voltage for the ADC in millivolts
> + */
> +struct at91_adc_data {
> +	unsigned long			channels_used;
> +	u8				num_channels;
> +	struct at91_adc_reg_desc	*registers;
> +	u8				startup_time;
> +	struct at91_adc_trigger		*trigger_list;
> +	u8				trigger_number;
> +	bool				use_external_triggers;
> +	u16				vref;
> +};
> +
> +extern void __init at91_add_device_adc(struct at91_adc_data *data);
> +#endif