From e5c003ae82865c43feca9e11fb291ec2304a63d1 Mon Sep 17 00:00:00 2001 From: Jonathan Cameron Date: Tue, 4 May 2010 14:42:59 +0100 Subject: [PATCH] staging:iio: Support functions for scan mask matching Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman --- drivers/staging/iio/iio.h | 45 +++++++++++++++++++++++++++++++++++---- 1 file changed, 41 insertions(+), 4 deletions(-) diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h index 71dbfe12b579..a12072a93cde 100644 --- a/drivers/staging/iio/iio.h +++ b/drivers/staging/iio/iio.h @@ -96,6 +96,7 @@ void iio_remove_event_from_list(struct iio_event_handler_list *el, * control method is used * @scan_count: [INTERN] the number of elements in the current scan mode * @scan_mask: [INTERN] bitmask used in masking scan mode elements + * @available_scan_masks: [DRIVER] optional array of allowed bitmasks * @scan_timestamp: [INTERN] does the scan mode include a timestamp * @trig: [INTERN] current device trigger (ring buffer modes) * @pollfunc: [DRIVER] function run on trigger being recieved @@ -122,7 +123,8 @@ struct iio_dev { struct attribute_group *scan_el_attrs; int scan_count; - u16 scan_mask; + u32 scan_mask; + u32 *available_scan_masks; bool scan_timestamp; struct iio_trigger *trig; struct iio_poll_func *pollfunc; @@ -132,22 +134,57 @@ struct iio_dev { * These are mainly provided to allow for a change of implementation if a device * has a large number of scan elements */ -#define IIO_MAX_SCAN_LENGTH 15 +#define IIO_MAX_SCAN_LENGTH 31 + +/* note 0 used as error indicator as it doesn't make sense. */ +static inline u32 iio_scan_mask_match(u32 *av_masks, u32 mask) +{ + while (*av_masks) { + if (!(~*av_masks & mask)) + return *av_masks; + av_masks++; + } + return 0; +} static inline int iio_scan_mask_query(struct iio_dev *dev_info, int bit) { + u32 mask; + if (bit > IIO_MAX_SCAN_LENGTH) return -EINVAL; + + if (!dev_info->scan_mask) + return 0; + + if (dev_info->available_scan_masks) + mask = iio_scan_mask_match(dev_info->available_scan_masks, + dev_info->scan_mask); else - return !!(dev_info->scan_mask & (1 << bit)); + mask = dev_info->scan_mask; + + if (!mask) + return -EINVAL; + + return !!(mask & (1 << bit)); }; static inline int iio_scan_mask_set(struct iio_dev *dev_info, int bit) { + u32 mask; + u32 trialmask = dev_info->scan_mask | (1 << bit); + if (bit > IIO_MAX_SCAN_LENGTH) return -EINVAL; - dev_info->scan_mask |= (1 << bit); + if (dev_info->available_scan_masks) { + mask = iio_scan_mask_match(dev_info->available_scan_masks, + trialmask); + if (!mask) + return -EINVAL; + } + dev_info->scan_mask = trialmask; dev_info->scan_count++; + return 0; }; -- 2.20.1