Commit b1c5d68e authored by Angelo Dureghello's avatar Angelo Dureghello Committed by Jonathan Cameron
Browse files

iio: dac: ad3552r-hs: add support for internal ramp 



The ad3552r can be feeded from the HDL controller by an internally
generated 16bit ramp, useful for debug pourposes. Add debugfs a file
to enable or disable it.

Signed-off-by: default avatarAngelo Dureghello <adureghello@baylibre.com>
Link: https://patch.msgid.link/20250409-wip-bl-ad3552r-fixes-v5-5-fb429c3a6515@baylibre.com


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent ca74d0eb

drivers/iio/dac/ad3552r-hs.c

+156 −6
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
 */



#include <linux/bitfield.h>

#include <linux/debugfs.h>

#include <linux/delay.h>

#include <linux/gpio/consumer.h>

#include <linux/iio/backend.h>
@@ -54,6 +55,18 @@ struct ad3552r_hs_state { 
	struct ad3552r_hs_platform_data *data;

	/* INTERFACE_CONFIG_D register cache, in DDR we cannot read values. */

	u32 config_d;

	/* Protects backend I/O operations from concurrent accesses. */

	struct mutex lock;

};



enum ad3552r_sources {

	AD3552R_SRC_NORMAL,

	AD3552R_SRC_RAMP_16BIT,

};



static const char * const dbgfs_attr_source[] = {

	[AD3552R_SRC_NORMAL] = "normal",

	[AD3552R_SRC_RAMP_16BIT] = "ramp-16bit",

};



static int ad3552r_hs_reg_read(struct ad3552r_hs_state *st, u32 reg, u32 *val,
@@ -65,6 +78,20 @@ static int ad3552r_hs_reg_read(struct ad3552r_hs_state *st, u32 reg, u32 *val, 
	return st->data->bus_reg_read(st->back, reg, val, xfer_size);

}



static int ad3552r_hs_set_data_source(struct ad3552r_hs_state *st,

				      enum iio_backend_data_source type)

{

	int i, ret;



	for (i = 0; i < st->model_data->num_hw_channels; ++i) {

		ret = iio_backend_data_source_set(st->back, i, type);

		if (ret)

			return ret;

	}



	return 0;

}



static int ad3552r_hs_update_reg_bits(struct ad3552r_hs_state *st, u32 reg,

				      u32 mask, u32 val, size_t xfer_size)

{
@@ -483,6 +510,103 @@ static int ad3552r_hs_reg_access(struct iio_dev *indio_dev, unsigned int reg, 
	return st->data->bus_reg_write(st->back, reg, writeval, 1);

}



static ssize_t ad3552r_hs_show_data_source(struct file *f, char __user *userbuf,

					   size_t count, loff_t *ppos)

{

	struct ad3552r_hs_state *st = file_inode(f)->i_private;

	enum iio_backend_data_source type;

	int idx, ret;



	guard(mutex)(&st->lock);



	ret = iio_backend_data_source_get(st->back, 0, &type);

	if (ret)

		return ret;



	switch (type) {

	case IIO_BACKEND_INTERNAL_RAMP_16BIT:

		idx = AD3552R_SRC_RAMP_16BIT;

		break;

	case IIO_BACKEND_EXTERNAL:

		idx = AD3552R_SRC_NORMAL;

		break;

	default:

		return -EINVAL;

	}



	return simple_read_from_buffer(userbuf, count, ppos,

				       dbgfs_attr_source[idx],

				       strlen(dbgfs_attr_source[idx]));

}



static ssize_t ad3552r_hs_write_data_source(struct file *f,

					    const char __user *userbuf,

					    size_t count, loff_t *ppos)

{

	struct ad3552r_hs_state *st = file_inode(f)->i_private;

	char buf[64];

	int ret, source;



	guard(mutex)(&st->lock);



	ret = simple_write_to_buffer(buf, sizeof(buf) - 1, ppos, userbuf,

				     count);

	if (ret < 0)

		return ret;



	buf[count] = '\0';



	ret = match_string(dbgfs_attr_source, ARRAY_SIZE(dbgfs_attr_source),

			   buf);

	if (ret < 0)

		return ret;



	switch (ret) {

	case AD3552R_SRC_RAMP_16BIT:

		source = IIO_BACKEND_INTERNAL_RAMP_16BIT;

		break;

	case AD3552R_SRC_NORMAL:

		source = IIO_BACKEND_EXTERNAL;

		break;

	default:

		return -EINVAL;

	}



	ret = ad3552r_hs_set_data_source(st, source);

	if (ret)

		return ret;



	return count;

}



static ssize_t ad3552r_hs_show_data_source_avail(struct file *f,

						 char __user *userbuf,

						 size_t count, loff_t *ppos)

{

	ssize_t len = 0;

	char buf[128];

	int i;



	for (i = 0; i < ARRAY_SIZE(dbgfs_attr_source); i++) {

		len += scnprintf(buf + len, PAGE_SIZE - len, "%s ",

				 dbgfs_attr_source[i]);

	}

	buf[len - 1] = '\n';



	return simple_read_from_buffer(userbuf, count, ppos, buf, len);

}



static const struct file_operations ad3552r_hs_data_source_fops = {

	.owner = THIS_MODULE,

	.write = ad3552r_hs_write_data_source,

	.read = ad3552r_hs_show_data_source,

};



static const struct file_operations ad3552r_hs_data_source_avail_fops = {

	.owner = THIS_MODULE,

	.read = ad3552r_hs_show_data_source_avail,

};



static int ad3552r_hs_setup(struct ad3552r_hs_state *st)

{

	u16 id;
@@ -550,11 +674,7 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st) 
	if (ret)

		return ret;



	ret = iio_backend_data_source_set(st->back, 0, IIO_BACKEND_EXTERNAL);

	if (ret)

		return ret;



	ret = iio_backend_data_source_set(st->back, 1, IIO_BACKEND_EXTERNAL);

	ret = ad3552r_hs_set_data_source(st, IIO_BACKEND_EXTERNAL);

	if (ret)

		return ret;
@@ -661,6 +781,26 @@ static const struct iio_info ad3552r_hs_info = { 
	.debugfs_reg_access = &ad3552r_hs_reg_access,

};



static void ad3552r_hs_debugfs_init(struct iio_dev *indio_dev)

{

	struct ad3552r_hs_state *st = iio_priv(indio_dev);

	struct dentry *d = iio_get_debugfs_dentry(indio_dev);



	if (!IS_ENABLED(CONFIG_DEBUG_FS))

		return;



	d = iio_get_debugfs_dentry(indio_dev);

	if (!d) {

		dev_warn(st->dev, "can't set debugfs in driver dir\n");

		return;

	}



	debugfs_create_file("data_source", 0600, d, st,

			    &ad3552r_hs_data_source_fops);

	debugfs_create_file("data_source_available", 0600, d, st,

			    &ad3552r_hs_data_source_avail_fops);

}



static int ad3552r_hs_probe(struct platform_device *pdev)

{

	struct ad3552r_hs_state *st;
@@ -705,7 +845,17 @@ static int ad3552r_hs_probe(struct platform_device *pdev) 
	if (ret)

		return ret;



	return devm_iio_device_register(&pdev->dev, indio_dev);

	ret = devm_iio_device_register(&pdev->dev, indio_dev);

	if (ret)

		return ret;



	ret = devm_mutex_init(&pdev->dev, &st->lock);

	if (ret)

		return ret;



	ad3552r_hs_debugfs_init(indio_dev);



	return ret;

}



static const struct of_device_id ad3552r_hs_of_id[] = {