Commit 25888dc5 authored by Jonathan Cameron's avatar Jonathan Cameron Committed by Greg Kroah-Hartman
Browse files

staging:iio:sca3000 extract old event handling and move to poll for events from buffer 



Fairly substantial rewrite as the code had bitrotted.
A rethink is needed for how to handle variable types in the new chan_spec world.

This patch restores sca3000 buffer usage to a working state.
V3: Rebase fixups.
V2: Move to new version of IIO_CHAN macro

Signed-off-by: default avatarJonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 1e3345bc

drivers/staging/iio/accel/sca3000.h

+22 −54
Original line number Diff line number Diff line
@@ -179,15 +179,15 @@ struct sca3000_state { 
	int				mo_det_use_count;

	struct mutex			lock;

	int				bpse;

	u8				*tx;

	/* not used during a ring buffer read */

	u8				*rx;

	/* Can these share a cacheline ? */

	u8				rx[2] ____cacheline_aligned;

	u8				tx[6] ____cacheline_aligned;

};



/**

 * struct sca3000_chip_info - model dependent parameters

 * @name:			model identification

 * @scale:			string containing floating point scale factor

 * @scale:			scale * 10^-6

 * @temp_output:		some devices have temperature sensors.

 * @measurement_mode_freq:	normal mode sampling frequency

 * @option_mode_1:		first optional mode. Not all models have one
@@ -200,28 +200,19 @@ struct sca3000_state { 
 **/

struct sca3000_chip_info {

	const char		*name;

	const char		*scale;

	unsigned int		scale;

	bool			temp_output;

	int			measurement_mode_freq;

	int			option_mode_1;

	int			option_mode_1_freq;

	int			option_mode_2;

	int			option_mode_2_freq;

	int			mot_det_mult_xz[6];

	int			mot_det_mult_y[7];

};



/**

 * sca3000_read_data() read a series of values from the device

 * @dev:		device

 * @reg_address_high:	start address (decremented read)

 * @rx:			pointer where received data is placed. Callee

 *			responsible for freeing this.

 * @len:		number of bytes to read

 *

 * The main lock must be held.

 **/

int sca3000_read_data(struct sca3000_state *st,

int sca3000_read_data_short(struct sca3000_state *st,

			    u8 reg_address_high,

		      u8 **rx_p,

			    int len);



/**
@@ -233,29 +224,6 @@ int sca3000_read_data(struct sca3000_state *st, 
 **/

int sca3000_write_reg(struct sca3000_state *st, u8 address, u8 val);



/* Conversion function for use with the ring buffer when in 11bit mode */

static inline int sca3000_11bit_convert(uint8_t msb, uint8_t lsb)

{

	int16_t val;



	val = ((lsb >> 3) & 0x1C) | (msb << 5);

	val |= (val & (1 << 12)) ? 0xE000 : 0;



	return val;

}



static inline int sca3000_13bit_convert(uint8_t msb, uint8_t lsb)

{

	s16 val;



	val = ((lsb >> 3) & 0x1F) | (msb << 5);

	/* sign fill */

	val |= (val & (1 << 12)) ? 0xE000 : 0;



	return val;

}





#ifdef CONFIG_IIO_RING_BUFFER

/**

 * sca3000_register_ring_funcs() setup the ring state change functions

drivers/staging/iio/accel/sca3000_core.c

+318 −573

File changed.

Preview size limit exceeded, changes collapsed.

drivers/staging/iio/accel/sca3000_ring.c

+170 −82
Original line number Diff line number Diff line
@@ -17,6 +17,8 @@ 
#include <linux/kernel.h>

#include <linux/spi/spi.h>

#include <linux/sysfs.h>

#include <linux/sched.h>

#include <linux/poll.h>



#include "../iio.h"

#include "../sysfs.h"
@@ -34,6 +36,44 @@ 
 * Currently scan elements aren't configured so it doesn't matter.

 */



static int sca3000_read_data(struct sca3000_state *st,

			    uint8_t reg_address_high,

			    u8 **rx_p,

			    int len)

{

	int ret;

	struct spi_message msg;

	struct spi_transfer xfer[2] = {

		{

			.len = 1,

			.tx_buf = st->tx,

		}, {

			.len = len,

		}

	};

	*rx_p = kmalloc(len, GFP_KERNEL);

	if (*rx_p == NULL) {

		ret = -ENOMEM;

		goto error_ret;

	}

	xfer[1].rx_buf = *rx_p;

	st->tx[0] = SCA3000_READ_REG(reg_address_high);

	spi_message_init(&msg);

	spi_message_add_tail(&xfer[0], &msg);

	spi_message_add_tail(&xfer[1], &msg);

	ret = spi_sync(st->us, &msg);

	if (ret) {

		dev_err(get_device(&st->us->dev), "problem reading register");

		goto error_free_rx;

	}



	return 0;

error_free_rx:

	kfree(*rx_p);

error_ret:

	return ret;

}



/**

 * sca3000_read_first_n_hw_rb() - main ring access, pulls data from ring

 * @r:			the ring
@@ -45,8 +85,6 @@ 
 * Currently does not provide timestamps.  As the hardware doesn't add them they

 * can only be inferred approximately from ring buffer events such as 50% full

 * and knowledge of when buffer was last emptied.  This is left to userspace.

 *

 * Temporarily deliberately broken.

 **/

static int sca3000_read_first_n_hw_rb(struct iio_ring_buffer *r,

				      size_t count, char __user *buf,
@@ -56,54 +94,45 @@ static int sca3000_read_first_n_hw_rb(struct iio_ring_buffer *r, 
	struct iio_dev *indio_dev = hw_ring->private;

	struct sca3000_state *st = indio_dev->dev_data;

	u8 *rx;

	s16 *samples;

	int ret, i, num_available, num_read = 0;

	int bytes_per_sample = 1;

	u8 *datas;

	u8 **data = &datas;



	if (st->bpse == 11)

		bytes_per_sample = 2;



	mutex_lock(&st->lock);

	/* Check how much data is available:

	 * RFC: Implement an ioctl to not bother checking whether there

	 * is enough data in the ring?  Afterall, if we are responding

	 * to an interrupt we have a minimum content guaranteed so it

	 * seems slight silly to waste time checking it is there.

	 */

	ret = sca3000_read_data(st,

				SCA3000_REG_ADDR_BUF_COUNT,

				&rx, 1);

	if (count % bytes_per_sample) {

		ret = -EINVAL;

		goto error_ret;

	}



	ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_BUF_COUNT, 1);

	if (ret)

		goto error_ret;

	else

		num_available = rx[1];

	/* num_available is the total number of samples available

		num_available = st->rx[0];

	/*

	 * num_available is the total number of samples available

	 * i.e. number of time points * number of channels.

	 */

	kfree(rx);

	if (count > num_available * bytes_per_sample)

		num_read = num_available*bytes_per_sample;

	else

		num_read = count - (count % (bytes_per_sample));

		num_read = count;



	/* Avoid the read request byte */

	*dead_offset = 1;

	ret = sca3000_read_data(st,

				SCA3000_REG_ADDR_RING_OUT,

				data, num_read);



	/* Convert byte order and shift to default resolution */

	if (st->bpse == 11) {

		samples = (s16*)(*data+1);

		for (i = 0; i < (num_read/2); i++) {

			samples[i] = be16_to_cpup(

					(__be16 *)&(samples[i]));

			samples[i] >>= 3;

		}

	}

				&rx, num_read);

	if (ret)

		goto error_ret;



	for (i = 0; i < num_read; i++)

		*(((u16 *)rx) + i) = be16_to_cpup((u16 *)rx + i);



	if (copy_to_user(buf, rx, num_read))

		ret = -EFAULT;

	kfree(rx);

	r->stufftoread = 0;

error_ret:

	mutex_unlock(&st->lock);
@@ -131,6 +160,76 @@ static IIO_RING_ENABLE_ATTR; 
static IIO_RING_BYTES_PER_DATUM_ATTR;

static IIO_RING_LENGTH_ATTR;



/**

 * sca3000_query_ring_int() is the hardware ring status interrupt enabled

 **/

static ssize_t sca3000_query_ring_int(struct device *dev,

				      struct device_attribute *attr,

				      char *buf)

{

	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

	int ret, val;

	struct iio_ring_buffer *ring = dev_get_drvdata(dev);

	struct iio_dev *indio_dev = ring->indio_dev;

	struct sca3000_state *st = indio_dev->dev_data;



	mutex_lock(&st->lock);

	ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);

	val = st->rx[0];

	mutex_unlock(&st->lock);

	if (ret)

		return ret;



	return sprintf(buf, "%d\n", !!(val & this_attr->address));

}



/**

 * sca3000_set_ring_int() set state of ring status interrupt

 **/

static ssize_t sca3000_set_ring_int(struct device *dev,

				      struct device_attribute *attr,

				      const char *buf,

				      size_t len)

{

	struct iio_ring_buffer *ring = dev_get_drvdata(dev);

	struct iio_dev *indio_dev = ring->indio_dev;

	struct sca3000_state *st = indio_dev->dev_data;

	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);

	long val;

	int ret;



	mutex_lock(&st->lock);

	ret = strict_strtol(buf, 10, &val);

	if (ret)

		goto error_ret;

	ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);

	if (ret)

		goto error_ret;

	if (val)

		ret = sca3000_write_reg(st,

					SCA3000_REG_ADDR_INT_MASK,

					st->rx[0] | this_attr->address);

	else

		ret = sca3000_write_reg(st,

					SCA3000_REG_ADDR_INT_MASK,

					st->rx[0] & ~this_attr->address);

error_ret:

	mutex_unlock(&st->lock);



	return ret ? ret : len;

}



static IIO_DEVICE_ATTR(50_percent, S_IRUGO | S_IWUSR,

		       sca3000_query_ring_int,

		       sca3000_set_ring_int,

		       SCA3000_INT_MASK_RING_HALF);



static IIO_DEVICE_ATTR(75_percent, S_IRUGO | S_IWUSR,

		       sca3000_query_ring_int,

		       sca3000_set_ring_int,

		       SCA3000_INT_MASK_RING_THREE_QUARTER);





/**

 * sca3000_show_ring_bpse() -sysfs function to query bits per sample from ring

 * @dev: ring buffer device
@@ -142,20 +241,18 @@ static ssize_t sca3000_show_ring_bpse(struct device *dev, 
				      char *buf)

{

	int len = 0, ret;

	u8 *rx;

	struct iio_ring_buffer *ring = dev_get_drvdata(dev);

	struct iio_dev *indio_dev = ring->indio_dev;

	struct sca3000_state *st = indio_dev->dev_data;



	mutex_lock(&st->lock);

	ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);

	ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);

	if (ret)

		goto error_ret;

	if (rx[1] & SCA3000_RING_BUF_8BIT)

	if (st->rx[0] & SCA3000_RING_BUF_8BIT)

		len = sprintf(buf, "s8/8\n");

	else

		len = sprintf(buf, "s11/16\n");

	kfree(rx);

error_ret:

	mutex_unlock(&st->lock);
@@ -178,20 +275,19 @@ static ssize_t sca3000_store_ring_bpse(struct device *dev, 
	struct iio_dev *indio_dev = ring->indio_dev;

	struct sca3000_state *st = indio_dev->dev_data;

	int ret;

	u8 *rx;



	mutex_lock(&st->lock);



	ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);

	ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);

	if (ret)

		goto error_ret;

	if (strncmp(buf, "s8/8", 4) == 0) {

	if (sysfs_streq(buf, "s8/8")) {

		ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,

					rx[1] | SCA3000_RING_BUF_8BIT);

					st->rx[0] | SCA3000_RING_BUF_8BIT);

		st->bpse = 8;

	} else if (strncmp(buf, "s11/16", 5) == 0) {

	} else if (sysfs_streq(buf, "s11/16")) {

		ret = sca3000_write_reg(st, SCA3000_REG_ADDR_MODE,

					rx[1] & ~SCA3000_RING_BUF_8BIT);

					st->rx[0] & ~SCA3000_RING_BUF_8BIT);

		st->bpse = 11;

	} else

		ret = -EINVAL;
@@ -201,32 +297,22 @@ error_ret: 
	return ret ? ret : len;

}



static IIO_SCAN_EL_C(accel_x, 0, 0, NULL);

static IIO_SCAN_EL_C(accel_y, 1, 0, NULL);

static IIO_SCAN_EL_C(accel_z, 2, 0, NULL);

static IIO_CONST_ATTR(accel_type_available, "s8/8 s11/16");

static IIO_DEVICE_ATTR(accel_type,

		       S_IRUGO | S_IWUSR,

		       sca3000_show_ring_bpse,

		       sca3000_store_ring_bpse,

		       0);

static ssize_t sca3000_show_buffer_scale(struct device *dev,

					 struct device_attribute *attr,

					 char *buf)

{

	struct iio_ring_buffer *ring = dev_get_drvdata(dev);

	struct iio_dev *indio_dev = ring->indio_dev;

	struct sca3000_state *st = indio_dev->dev_data;



static struct attribute *sca3000_scan_el_attrs[] = {

	&iio_scan_el_accel_x.dev_attr.attr,

	&iio_const_attr_accel_x_index.dev_attr.attr,

	&iio_scan_el_accel_y.dev_attr.attr,

	&iio_const_attr_accel_y_index.dev_attr.attr,

	&iio_scan_el_accel_z.dev_attr.attr,

	&iio_const_attr_accel_z_index.dev_attr.attr,

	&iio_const_attr_accel_type_available.dev_attr.attr,

	&iio_dev_attr_accel_type.dev_attr.attr,

	NULL

};

	return sprintf(buf, "0.%06d\n", 4*st->info->scale);

}



static struct attribute_group sca3000_scan_el_group = {

	.attrs = sca3000_scan_el_attrs,

	.name = "scan_elements",

};

static IIO_DEVICE_ATTR(accel_scale,

		       S_IRUGO,

		       sca3000_show_buffer_scale,

		       NULL,

		       0);



/*

 * Ring buffer attributes
@@ -238,6 +324,9 @@ static struct attribute *sca3000_ring_attributes[] = { 
	&dev_attr_length.attr,

	&dev_attr_bytes_per_datum.attr,

	&dev_attr_enable.attr,

	&iio_dev_attr_50_percent.dev_attr.attr,

	&iio_dev_attr_75_percent.dev_attr.attr,

	&iio_dev_attr_accel_scale.dev_attr.attr,

	NULL,

};
@@ -263,11 +352,12 @@ static struct iio_ring_buffer *sca3000_rb_allocate(struct iio_dev *indio_dev) 
	ring = kzalloc(sizeof *ring, GFP_KERNEL);

	if (!ring)

		return NULL;



	ring->private = indio_dev;

	buf = &ring->buf;

	buf->stufftoread = 0;

	iio_ring_buffer_init(buf, indio_dev);

	buf->dev.type = &sca3000_ring_type;

	device_initialize(&buf->dev);

	buf->dev.parent = &indio_dev->dev;

	dev_set_drvdata(&buf->dev, (void *)buf);
@@ -287,10 +377,14 @@ int sca3000_configure_ring(struct iio_dev *indio_dev) 
		return -ENOMEM;

	indio_dev->modes |= INDIO_RING_HARDWARE_BUFFER;



	indio_dev->ring->scan_el_attrs = &sca3000_scan_el_group;

	indio_dev->ring->access.read_first_n = &sca3000_read_first_n_hw_rb;

	indio_dev->ring->access.get_length = &sca3000_ring_get_length;

	indio_dev->ring->access.get_bytes_per_datum = &sca3000_ring_get_bytes_per_datum;

	indio_dev->ring->access.get_bytes_per_datum =

		&sca3000_ring_get_bytes_per_datum;



	iio_scan_mask_set(indio_dev->ring, 0);

	iio_scan_mask_set(indio_dev->ring, 1);

	iio_scan_mask_set(indio_dev->ring, 2);



	return 0;

}
@@ -305,22 +399,20 @@ int __sca3000_hw_ring_state_set(struct iio_dev *indio_dev, bool state) 
{

	struct sca3000_state *st = indio_dev->dev_data;

	int ret;

	u8 *rx;



	mutex_lock(&st->lock);

	ret = sca3000_read_data(st, SCA3000_REG_ADDR_MODE, &rx, 1);

	ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);

	if (ret)

		goto error_ret;

	if (state) {

		printk(KERN_INFO "supposedly enabling ring buffer\n");

		ret = sca3000_write_reg(st,

					SCA3000_REG_ADDR_MODE,

					(rx[1] | SCA3000_RING_BUF_ENABLE));

					(st->rx[0] | SCA3000_RING_BUF_ENABLE));

	} else

		ret = sca3000_write_reg(st,

					SCA3000_REG_ADDR_MODE,

					(rx[1] & ~SCA3000_RING_BUF_ENABLE));

	kfree(rx);

					(st->rx[0] & ~SCA3000_RING_BUF_ENABLE));

error_ret:

	mutex_unlock(&st->lock);
@@ -357,13 +449,9 @@ void sca3000_register_ring_funcs(struct iio_dev *indio_dev) 
 **/

void sca3000_ring_int_process(u8 val, struct iio_ring_buffer *ring)

{

	/*

	if (val & SCA3000_INT_STATUS_THREE_QUARTERS)

		iio_push_ring_event(ring,

				    IIO_EVENT_CODE_RING_75_FULL,

				    0);

	else if (val & SCA3000_INT_STATUS_HALF)

		iio_push_ring_event(ring,

				    IIO_EVENT_CODE_RING_50_FULL, 0);

	*/

	if (val & (SCA3000_INT_STATUS_THREE_QUARTERS |

		   SCA3000_INT_STATUS_HALF)) {

		ring->stufftoread = true;

		wake_up_interruptible(&ring->pollq);

	}

}

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