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 <daniel.baluta@xxxxxxxxx> --- drivers/iio/dummy/Kconfig | 1 + drivers/iio/dummy/iio_simple_dummy.c | 102 +++++++++++++---------------------- 2 files changed, 38 insertions(+), 65 deletions(-) diff --git a/drivers/iio/dummy/Kconfig b/drivers/iio/dummy/Kconfig index 71805ce..aa5824d 100644 --- a/drivers/iio/dummy/Kconfig +++ b/drivers/iio/dummy/Kconfig @@ -10,6 +10,7 @@ config IIO_DUMMY_EVGEN config IIO_SIMPLE_DUMMY tristate "An example driver with no hardware requirements" + depends on IIO_SW_DEVICE help Driver intended mainly as documentation for how to write a driver. May also be useful for testing userspace code diff --git a/drivers/iio/dummy/iio_simple_dummy.c b/drivers/iio/dummy/iio_simple_dummy.c index 43fe4ba..ad3410e 100644 --- a/drivers/iio/dummy/iio_simple_dummy.c +++ b/drivers/iio/dummy/iio_simple_dummy.c @@ -17,26 +17,18 @@ #include <linux/kernel.h> #include <linux/slab.h> #include <linux/module.h> +#include <linux/string.h> #include <linux/iio/iio.h> #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 +564,18 @@ 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 +606,7 @@ 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 +617,7 @@ 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 = kstrdup(name, GFP_KERNEL); /* Provide description of available channels */ indio_dev->channels = iio_dummy_channels; @@ -646,7 +644,9 @@ 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 +654,18 @@ 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 +673,7 @@ 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); @@ -684,11 +686,13 @@ static void iio_dummy_remove(int index) iio_simple_dummy_events_unregister(indio_dev); /* Free all structures */ + kfree(indio_dev->name); iio_device_free(indio_dev); -} + 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 +701,18 @@ 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 <jic23@xxxxxxxxxx>"); MODULE_DESCRIPTION("IIO dummy driver"); -- 2.5.0 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html