On 20/04/16 16:45, Daniel Baluta wrote:
> We register a new device type named "dummy", this will create a
> configfs entry under:
> * /config/iio/devices/dummy.
>
> Creating dummy devices is now as simple as:
>
> $ mkdir /config/iio/devices/dummy/my_dummy_device
>
> Signed-off-by: Daniel Baluta <[email protected]>
Looks very nice.
I don't think it is unreasonable to demand people have configfs for
the dummy driver so very happy to have this cleaned up.
Now to try it with a few thousand devices and see what breaks ;)
1 trivial point inline.
Jonathan
> ---
> drivers/iio/dummy/iio_simple_dummy.c | 98
> ++++++++++++------------------------
> 1 file changed, 33 insertions(+), 65 deletions(-)
>
> diff --git a/drivers/iio/dummy/iio_simple_dummy.c
> b/drivers/iio/dummy/iio_simple_dummy.c
> index 43fe4ba..65f92f8 100644
> --- a/drivers/iio/dummy/iio_simple_dummy.c
> +++ b/drivers/iio/dummy/iio_simple_dummy.c
> @@ -22,21 +22,12 @@
> #include <linux/iio/sysfs.h>
> #include <linux/iio/events.h>
> #include <linux/iio/buffer.h>
> +#include <linux/iio/sw_device.h>
> #include "iio_simple_dummy.h"
>
> -/*
> - * A few elements needed to fake a bus for this driver
> - * Note instances parameter controls how many of these
> - * dummy devices are registered.
> - */
> -static unsigned instances = 1;
> -module_param(instances, uint, 0);
> -
> -/* Pointer array used to fake bus elements */
> -static struct iio_dev **iio_dummy_devs;
> -
> -/* Fake a name for the part number, usually obtained from the id table */
> -static const char *iio_dummy_part_number = "iio_dummy_part_no";
> +static struct config_item_type iio_dummy_type = {
> + .ct_owner = THIS_MODULE,
> +};
>
> /**
> * struct iio_dummy_accel_calibscale - realworld to register mapping
> @@ -572,12 +563,18 @@ static int iio_dummy_init_device(struct iio_dev
> *indio_dev)
> * const struct i2c_device_id *id)
> * SPI: iio_dummy_probe(struct spi_device *spi)
> */
> -static int iio_dummy_probe(int index)
> +static struct iio_sw_device *iio_dummy_probe(const char *name)
> {
> int ret;
> struct iio_dev *indio_dev;
> struct iio_dummy_state *st;
> + struct iio_sw_device *swd;
>
> + swd = kzalloc(sizeof(*swd), GFP_KERNEL);
> + if (!swd) {
> + ret = -ENOMEM;
> + goto error_kzalloc;
> + }
> /*
> * Allocate an IIO device.
> *
> @@ -608,7 +605,7 @@ static int iio_dummy_probe(int index)
> * i2c_set_clientdata(client, indio_dev);
> * spi_set_drvdata(spi, indio_dev);
> */
> - iio_dummy_devs[index] = indio_dev;
> + swd->device = indio_dev;
>
> /*
> * Set the device name.
> @@ -619,7 +616,7 @@ static int iio_dummy_probe(int index)
> * indio_dev->name = id->name;
> * indio_dev->name = spi_get_device_id(spi)->name;
> */
> - indio_dev->name = iio_dummy_part_number;
> + indio_dev->name = name;
>
> /* Provide description of available channels */
> indio_dev->channels = iio_dummy_channels;
> @@ -646,7 +643,8 @@ static int iio_dummy_probe(int index)
> if (ret < 0)
> goto error_unconfigure_buffer;
>
> - return 0;
> + iio_swd_group_init_type_name(swd, name, &iio_dummy_type);
> + return swd;
> error_unconfigure_buffer:
> iio_simple_dummy_unconfigure_buffer(indio_dev);
> error_unregister_events:
> @@ -654,16 +652,18 @@ error_unregister_events:
> error_free_device:
> iio_device_free(indio_dev);
> error_ret:
> - return ret;
> + kfree(swd);
> +error_kzalloc:
> + return ERR_PTR(ret);
> }
>
> /**
> * iio_dummy_remove() - device instance removal function
> - * @index: device index.
> + * @swd: pointer to software IIO device abstraction
> *
> * Parameters follow those of iio_dummy_probe for buses.
> */
> -static void iio_dummy_remove(int index)
> +static int iio_dummy_remove(struct iio_sw_device *swd)
> {
> /*
> * Get a pointer to the device instance iio_dev structure
> @@ -671,7 +671,7 @@ static void iio_dummy_remove(int index)
> * struct iio_dev *indio_dev = i2c_get_clientdata(client);
> * struct iio_dev *indio_dev = spi_get_drvdata(spi);
> */
> - struct iio_dev *indio_dev = iio_dummy_devs[index];
> + struct iio_dev *indio_dev = swd->device;
>
> /* Unregister the device */
> iio_device_unregister(indio_dev);
> @@ -685,10 +685,10 @@ static void iio_dummy_remove(int index)
>
> /* Free all structures */
> iio_device_free(indio_dev);
blank line here (nitpick of the day ;)
> + return 0;
> }
> -
> /**
> - * iio_dummy_init() - device driver registration
> + * module_iio_sw_device_driver() - device driver registration
> *
> * Varies depending on bus type of the device. As there is no device
> * here, call probe directly. For information on device registration
> @@ -697,50 +697,18 @@ static void iio_dummy_remove(int index)
> * spi:
> * Documentation/spi/spi-summary
> */
> -static __init int iio_dummy_init(void)
> -{
> - int i, ret;
> -
> - if (instances > 10) {
> - instances = 1;
> - return -EINVAL;
> - }
> -
> - /* Fake a bus */
> - iio_dummy_devs = kcalloc(instances, sizeof(*iio_dummy_devs),
> - GFP_KERNEL);
> - /* Here we have no actual device so call probe */
> - for (i = 0; i < instances; i++) {
> - ret = iio_dummy_probe(i);
> - if (ret < 0)
> - goto error_remove_devs;
> - }
> - return 0;
> -
> -error_remove_devs:
> - while (i--)
> - iio_dummy_remove(i);
> -
> - kfree(iio_dummy_devs);
> - return ret;
> -}
> -module_init(iio_dummy_init);
> +static const struct iio_sw_device_ops iio_dummy_device_ops = {
> + .probe = iio_dummy_probe,
> + .remove = iio_dummy_remove,
> +};
>
> -/**
> - * iio_dummy_exit() - device driver removal
> - *
> - * Varies depending on bus type of the device.
> - * As there is no device here, call remove directly.
> - */
> -static __exit void iio_dummy_exit(void)
> -{
> - int i;
> +static struct iio_sw_device_type iio_dummy_device = {
> + .name = "dummy",
> + .owner = THIS_MODULE,
> + .ops = &iio_dummy_device_ops,
> +};
>
> - for (i = 0; i < instances; i++)
> - iio_dummy_remove(i);
> - kfree(iio_dummy_devs);
> -}
> -module_exit(iio_dummy_exit);
> +module_iio_sw_device_driver(iio_dummy_device);
>
> MODULE_AUTHOR("Jonathan Cameron <[email protected]>");
> MODULE_DESCRIPTION("IIO dummy driver");
>
