diff options
Diffstat (limited to 'drivers/staging/iio/Documentation')
| -rw-r--r-- | drivers/staging/iio/Documentation/dac/max517 | 41 | ||||
| -rw-r--r-- | drivers/staging/iio/Documentation/generic_buffer.c | 66 | ||||
| -rw-r--r-- | drivers/staging/iio/Documentation/iio_utils.h | 63 | ||||
| -rw-r--r-- | drivers/staging/iio/Documentation/sysfs-bus-iio | 81 | ||||
| -rw-r--r-- | drivers/staging/iio/Documentation/sysfs-bus-iio-trigger-sysfs | 11 |
5 files changed, 217 insertions, 45 deletions
diff --git a/drivers/staging/iio/Documentation/dac/max517 b/drivers/staging/iio/Documentation/dac/max517 new file mode 100644 index 000000000000..e60ec2f91a7a --- /dev/null +++ b/drivers/staging/iio/Documentation/dac/max517 @@ -0,0 +1,41 @@ +Kernel driver max517 +==================== + +Supported chips: + * Maxim MAX517, MAX518, MAX519 + Prefix: 'max517' + Datasheet: Publicly available at the Maxim website + http://www.maxim-ic.com/ + +Author: + Roland Stigge <stigge@antcom.de> + +Description +----------- + +The Maxim MAX517/518/519 is an 8-bit DAC on the I2C bus. The following table +shows the different feature sets of the variants MAX517, MAX518 and MAX519: + +Feature MAX517 MAX518 MAX519 +-------------------------------------------------------------------------- +One output channel X +Two output channels X X +Simultaneous output updates X X +Supply voltage as reference X +Separate reference input X +Reference input for each DAC X + +Via the iio sysfs interface, there are three attributes available: out1_raw, +out2_raw and out12_raw. With out1_raw and out2_raw, the current output values +(0..255) of the DACs can be written to the device. out12_raw can be used to set +both output channel values simultaneously. + +With MAX517, only out1_raw is available. + +Via out1_scale (and where appropriate, out2_scale), the current scaling factor +in mV can be read. + +When the operating system goes to a power down state, the Power Down function +of the chip is activated, reducing the supply current to 4uA. + +On power-up, the device is in 0V-output state. diff --git a/drivers/staging/iio/Documentation/generic_buffer.c b/drivers/staging/iio/Documentation/generic_buffer.c index df23aeb9d529..3cc18ab4ebfd 100644 --- a/drivers/staging/iio/Documentation/generic_buffer.c +++ b/drivers/staging/iio/Documentation/generic_buffer.c @@ -26,11 +26,9 @@ #include <sys/stat.h> #include <sys/dir.h> #include <linux/types.h> +#include <string.h> #include "iio_utils.h" -const int buf_len = 128; -const int num_loops = 2; - /** * size_from_channelarray() - calculate the storage size of a scan * @channels: the channel info array @@ -118,6 +116,11 @@ void process_scan(char *data, int main(int argc, char **argv) { + unsigned long num_loops = 2; + unsigned long timedelay = 1000000; + unsigned long buf_len = 128; + + int ret, c, i, j, toread; FILE *fp_ev; @@ -134,10 +137,12 @@ int main(int argc, char **argv) int dev_num, trig_num; char *buffer_access, *buffer_event; int scan_size; + int noevents = 0; + char *dummy; struct iio_channel_info *infoarray; - while ((c = getopt(argc, argv, "t:n:")) != -1) { + while ((c = getopt(argc, argv, "l:w:c:et:n:")) != -1) { switch (c) { case 'n': device_name = optarg; @@ -146,11 +151,26 @@ int main(int argc, char **argv) trigger_name = optarg; datardytrigger = 0; break; + case 'e': + noevents = 1; + break; + case 'c': + num_loops = strtoul(optarg, &dummy, 10); + break; + case 'w': + timedelay = strtoul(optarg, &dummy, 10); + break; + case 'l': + buf_len = strtoul(optarg, &dummy, 10); + break; case '?': return -1; } } + if (device_name == NULL) + return -1; + /* Find the device requested */ dev_num = find_type_by_name(device_name, "device"); if (dev_num < 0) { @@ -260,22 +280,30 @@ int main(int argc, char **argv) /* Wait for events 10 times */ for (j = 0; j < num_loops; j++) { - read_size = fread(&dat, 1, sizeof(struct iio_event_data), - fp_ev); - switch (dat.id) { - case IIO_EVENT_CODE_RING_100_FULL: - toread = buf_len; - break; - case IIO_EVENT_CODE_RING_75_FULL: - toread = buf_len*3/4; - break; - case IIO_EVENT_CODE_RING_50_FULL: - toread = buf_len/2; - break; - default: - printf("Unexpecteded event code\n"); - continue; + if (!noevents) { + read_size = fread(&dat, + 1, + sizeof(struct iio_event_data), + fp_ev); + switch (dat.id) { + case IIO_EVENT_CODE_RING_100_FULL: + toread = buf_len; + break; + case IIO_EVENT_CODE_RING_75_FULL: + toread = buf_len*3/4; + break; + case IIO_EVENT_CODE_RING_50_FULL: + toread = buf_len/2; + break; + default: + printf("Unexpecteded event code\n"); + continue; + } + } else { + usleep(timedelay); + toread = 64; } + read_size = read(fp, data, toread*scan_size); diff --git a/drivers/staging/iio/Documentation/iio_utils.h b/drivers/staging/iio/Documentation/iio_utils.h index 03724246b95a..8095727b3966 100644 --- a/drivers/staging/iio/Documentation/iio_utils.h +++ b/drivers/staging/iio/Documentation/iio_utils.h @@ -51,7 +51,7 @@ static int iioutils_break_up_name(const char *full_name, w = working; r = working; - while(*r != '\0') { + while (*r != '\0') { if (!isdigit(*r)) { *w = *r; w++; @@ -113,7 +113,7 @@ inline int iioutils_get_type(unsigned *is_signed, DIR *dp; char *scan_el_dir, *builtname, *builtname_generic, *filename = 0; char signchar; - unsigned sizeint, padint; + unsigned padint; const struct dirent *ent; ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir); @@ -159,7 +159,7 @@ inline int iioutils_get_type(unsigned *is_signed, fscanf(sysfsfp, "%c%u/%u", &signchar, bits_used, &padint); *bytes = padint / 8; - if (sizeint == 64) + if (*bits_used == 64) *mask = ~0; else *mask = (1 << *bits_used) - 1; @@ -242,6 +242,26 @@ error_ret: return ret; } +/** + * bsort_channel_array_by_index() - reorder so that the array is in index order + * + **/ + +inline void bsort_channel_array_by_index(struct iio_channel_info **ci_array, + int cnt) +{ + + struct iio_channel_info temp; + int x, y; + + for (x = 0; x < cnt; x++) + for (y = 0; y < (cnt - 1); y++) + if ((*ci_array)[y].index > (*ci_array)[y+1].index) { + temp = (*ci_array)[y + 1]; + (*ci_array)[y + 1] = (*ci_array)[y]; + (*ci_array)[y] = temp; + } +} /** * build_channel_array() - function to figure out what channels are present @@ -254,7 +274,7 @@ inline int build_channel_array(const char *device_dir, { DIR *dp; FILE *sysfsfp; - int count = 0, temp, i; + int count, temp, i; struct iio_channel_info *current; int ret; const struct dirent *ent; @@ -293,12 +313,13 @@ inline int build_channel_array(const char *device_dir, fclose(sysfsfp); free(filename); } - *ci_array = malloc(sizeof(**ci_array)*(*counter)); + *ci_array = malloc(sizeof(**ci_array) * (*counter)); if (*ci_array == NULL) { ret = -ENOMEM; goto error_close_dir; } seekdir(dp, 0); + count = 0; while (ent = readdir(dp), ent != NULL) { if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"), "_en") == 0) { @@ -319,7 +340,13 @@ inline int build_channel_array(const char *device_dir, } fscanf(sysfsfp, "%u", ¤t->enabled); fclose(sysfsfp); - free(filename); + + if (!current->enabled) { + free(filename); + count--; + continue; + } + current->scale = 1.0; current->offset = 0; current->name = strndup(ent->d_name, @@ -374,31 +401,15 @@ inline int build_channel_array(const char *device_dir, current->generic_name); } } - /* reorder so that the array is in index order*/ - current = malloc(sizeof(**ci_array)**counter); - if (current == NULL) { - ret = -ENOMEM; - goto error_cleanup_array; - } + closedir(dp); - count = 0; - temp = 0; - while (count < *counter) - for (i = 0; i < *counter; i++) - if ((*ci_array)[i].index == temp) { - memcpy(¤t[count++], - &(*ci_array)[i], - sizeof(*current)); - temp++; - break; - } - free(*ci_array); - *ci_array = current; + /* reorder so that the array is in index order */ + bsort_channel_array_by_index(ci_array, *counter); return 0; error_cleanup_array: - for (i = count - 1; i >= 0; i++) + for (i = count - 1; i >= 0; i--) free((*ci_array)[i].name); free(*ci_array); error_close_dir: diff --git a/drivers/staging/iio/Documentation/sysfs-bus-iio b/drivers/staging/iio/Documentation/sysfs-bus-iio index 2dde97de75f8..4915aee14d88 100644 --- a/drivers/staging/iio/Documentation/sysfs-bus-iio +++ b/drivers/staging/iio/Documentation/sysfs-bus-iio @@ -53,6 +53,31 @@ Description: When the internal sampling clock can only take a small discrete set of values, this file lists those available. +What: /sys/bus/iio/devices/deviceX/range +KernelVersion: 2.6.38 +Contact: linux-iio@vger.kernel.org +Description: + Hardware dependent ADC Full Scale Range in mVolt. + +What: /sys/bus/iio/devices/deviceX/range_available +KernelVersion: 2.6.38 +Contact: linux-iio@vger.kernel.org +Description: + Hardware dependent supported vales for ADC Full Scale Range. + +What: /sys/bus/iio/devices/deviceX/oversampling_ratio +KernelVersion: 2.6.38 +Contact: linux-iio@vger.kernel.org +Description: + Hardware dependent ADC oversampling. Controls the sampling ratio + of the digital filter if available. + +What: /sys/bus/iio/devices/deviceX/oversampling_ratio_available +KernelVersion: 2.6.38 +Contact: linux-iio@vger.kernel.org +Description: + Hardware dependent values supported by the oversampling filter. + What: /sys/bus/iio/devices/deviceX/inY_raw What: /sys/bus/iio/devices/deviceX/inY_supply_raw KernelVersion: 2.6.35 @@ -86,6 +111,12 @@ Description: sensor is associated with one part of a compound device (e.g. a gyroscope axis). +What: /sys/bus/iio/devices/deviceX/tempX_input +KernelVersion: 2.6.38 +Contact: linux-iio@vger.kernel.org +Description: + Scaled temperature measurement in milli degrees Celsius. + What: /sys/bus/iio/devices/deviceX/accel_x_raw What: /sys/bus/iio/devices/deviceX/accel_y_raw What: /sys/bus/iio/devices/deviceX/accel_z_raw @@ -168,6 +199,7 @@ Description: What: /sys/bus/iio/devices/deviceX/inY_scale What: /sys/bus/iio/devices/deviceX/inY_supply_scale What: /sys/bus/iio/devices/deviceX/in_scale +What: /sys/bus/iio/devices/deviceX/outY_scale What: /sys/bus/iio/devices/deviceX/accel_scale What: /sys/bus/iio/devices/deviceX/accel_peak_scale What: /sys/bus/iio/devices/deviceX/gyro_scale @@ -222,6 +254,55 @@ Description: If a discrete set of scale values are available, they are listed in this attribute. +What: /sys/bus/iio/devices/deviceX/outY_raw +KernelVersion: 2.6.37 +Contact: linux-iio@vger.kernel.org +Description: + Raw (unscaled, no bias etc.) output voltage for + channel Y. The number must always be specified and + unique if the output corresponds to a single channel. + +What: /sys/bus/iio/devices/deviceX/outY&Z_raw +KernelVersion: 2.6.37 +Contact: linux-iio@vger.kernel.org +Description: + Raw (unscaled, no bias etc.) output voltage for an aggregate of + channel Y, channel Z, etc. This interface is available in cases + where a single output sets the value for multiple channels + simultaneously. + +What: /sys/bus/iio/devices/deviceX/outY_powerdown_mode +What: /sys/bus/iio/devices/deviceX/out_powerdown_mode +KernelVersion: 2.6.38 +Contact: linux-iio@vger.kernel.org +Description: + Specifies the output powerdown mode. + DAC output stage is disconnected from the amplifier and + 1kohm_to_gnd: connected to ground via an 1kOhm resistor + 100kohm_to_gnd: connected to ground via an 100kOhm resistor + three_state: left floating + For a list of available output power down options read + outX_powerdown_mode_available. If Y is not present the + mode is shared across all outputs. + +What: /sys/bus/iio/devices/deviceX/outY_powerdown_mode_available +What: /sys/bus/iio/devices/deviceX/out_powerdown_mode_available +KernelVersion: 2.6.38 +Contact: linux-iio@vger.kernel.org +Description: + Lists all available output power down modes. + If Y is not present the mode is shared across all outputs. + +What: /sys/bus/iio/devices/deviceX/outY_powerdown +What: /sys/bus/iio/devices/deviceX/out_powerdown +KernelVersion: 2.6.38 +Contact: linux-iio@vger.kernel.org +Description: + Writing 1 causes output Y to enter the power down mode specified + by the corresponding outY_powerdown_mode. Clearing returns to + normal operation. Y may be suppressed if all outputs are + controlled together. + What: /sys/bus/iio/devices/deviceX/deviceX:eventY KernelVersion: 2.6.35 Contact: linux-iio@vger.kernel.org diff --git a/drivers/staging/iio/Documentation/sysfs-bus-iio-trigger-sysfs b/drivers/staging/iio/Documentation/sysfs-bus-iio-trigger-sysfs new file mode 100644 index 000000000000..5235e6c749ab --- /dev/null +++ b/drivers/staging/iio/Documentation/sysfs-bus-iio-trigger-sysfs @@ -0,0 +1,11 @@ +What: /sys/bus/iio/devices/triggerX/trigger_now +KernelVersion: 2.6.38 +Contact: linux-iio@vger.kernel.org +Description: + This file is provided by the iio-trig-sysfs stand-alone trigger + driver. Writing this file with any value triggers an event + driven driver, associated with this trigger, to capture data + into an in kernel buffer. This approach can be valuable during + automated testing or in situations, where other trigger methods + are not applicable. For example no RTC or spare GPIOs. + X is the IIO index of the trigger. |