diff options
Diffstat (limited to 'drivers/iio/industrialio-gts-helper.c')
| -rw-r--r-- | drivers/iio/industrialio-gts-helper.c | 391 |
1 files changed, 279 insertions, 112 deletions
diff --git a/drivers/iio/industrialio-gts-helper.c b/drivers/iio/industrialio-gts-helper.c index b51eb6cb766f..f35c36fd4a55 100644 --- a/drivers/iio/industrialio-gts-helper.c +++ b/drivers/iio/industrialio-gts-helper.c @@ -134,7 +134,7 @@ int iio_gts_total_gain_to_scale(struct iio_gts *gts, int total_gain, return iio_gts_delinearize(tmp, NANO, scale_int, scale_nano); } -EXPORT_SYMBOL_NS_GPL(iio_gts_total_gain_to_scale, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_total_gain_to_scale, "IIO_GTS_HELPER"); /** * iio_gts_purge_avail_scale_table - free-up the available scale tables @@ -160,16 +160,123 @@ static void iio_gts_purge_avail_scale_table(struct iio_gts *gts) gts->num_avail_all_scales = 0; } +static int scale_eq(int *sc1, int *sc2) +{ + return sc1[0] == sc2[0] && sc1[1] == sc2[1]; +} + +static int scale_smaller(int *sc1, int *sc2) +{ + if (sc1[0] != sc2[0]) + return sc1[0] < sc2[0]; + + /* If integer parts are equal, fixp parts */ + return sc1[1] < sc2[1]; +} + +/* + * Do a single table listing all the unique scales that any combination of + * supported gains and times can provide. + */ +static int do_combined_scaletable(struct iio_gts *gts, + size_t all_scales_tbl_bytes) +{ + int t_idx, i, new_idx; + int **scales = gts->per_time_avail_scale_tables; + int *all_scales = kcalloc(gts->num_itime, all_scales_tbl_bytes, + GFP_KERNEL); + + if (!all_scales) + return -ENOMEM; + /* + * Create table containing all of the supported scales by looping + * through all of the per-time scales and copying the unique scales + * into one sorted table. + * + * We assume all the gains for same integration time were unique. + * It is likely the first time table had greatest time multiplier as + * the times are in the order of preference and greater times are + * usually preferred. Hence we start from the last table which is likely + * to have the smallest total gains. + */ + t_idx = gts->num_itime - 1; + memcpy(all_scales, scales[t_idx], all_scales_tbl_bytes); + new_idx = gts->num_hwgain * 2; + + while (t_idx-- > 0) { + for (i = 0; i < gts->num_hwgain ; i++) { + int *candidate = &scales[t_idx][i * 2]; + int chk; + + if (scale_smaller(candidate, &all_scales[new_idx - 2])) { + all_scales[new_idx] = candidate[0]; + all_scales[new_idx + 1] = candidate[1]; + new_idx += 2; + + continue; + } + for (chk = 0; chk < new_idx; chk += 2) + if (!scale_smaller(candidate, &all_scales[chk])) + break; + + if (scale_eq(candidate, &all_scales[chk])) + continue; + + memmove(&all_scales[chk + 2], &all_scales[chk], + (new_idx - chk) * sizeof(int)); + all_scales[chk] = candidate[0]; + all_scales[chk + 1] = candidate[1]; + new_idx += 2; + } + } + + gts->num_avail_all_scales = new_idx / 2; + gts->avail_all_scales_table = all_scales; + + return 0; +} + +static void iio_gts_free_int_table_array(int **arr, int num_tables) +{ + int i; + + for (i = 0; i < num_tables; i++) + kfree(arr[i]); + + kfree(arr); +} + +static int iio_gts_alloc_int_table_array(int ***arr, int num_tables, int num_table_items) +{ + int i, **tmp; + + tmp = kcalloc(num_tables, sizeof(**arr), GFP_KERNEL); + if (!tmp) + return -ENOMEM; + + for (i = 0; i < num_tables; i++) { + tmp[i] = kcalloc(num_table_items, sizeof(int), GFP_KERNEL); + if (!tmp[i]) + goto err_free; + } + + *arr = tmp; + + return 0; +err_free: + iio_gts_free_int_table_array(tmp, i); + + return -ENOMEM; +} + static int iio_gts_gain_cmp(const void *a, const void *b) { return *(int *)a - *(int *)b; } -static int gain_to_scaletables(struct iio_gts *gts, int **gains, int **scales) +static int fill_and_sort_scaletables(struct iio_gts *gts, int **gains, int **scales) { - int ret, i, j, new_idx, time_idx; - int *all_gains; - size_t gain_bytes; + int i, j, ret; for (i = 0; i < gts->num_itime; i++) { /* @@ -189,71 +296,69 @@ static int gain_to_scaletables(struct iio_gts *gts, int **gains, int **scales) } } - gain_bytes = array_size(gts->num_hwgain, sizeof(int)); - all_gains = kcalloc(gts->num_itime, gain_bytes, GFP_KERNEL); - if (!all_gains) - return -ENOMEM; + return 0; +} + +static void compute_per_time_gains(struct iio_gts *gts, int **gains) +{ + int i, j; + + for (i = 0; i < gts->num_itime; i++) { + for (j = 0; j < gts->num_hwgain; j++) + gains[i][j] = gts->hwgain_table[j].gain * + gts->itime_table[i].mul; + } +} + +static int compute_per_time_tables(struct iio_gts *gts, int **scales) +{ + int **per_time_gains; + int ret; /* - * We assume all the gains for same integration time were unique. - * It is likely the first time table had greatest time multiplier as - * the times are in the order of preference and greater times are - * usually preferred. Hence we start from the last table which is likely - * to have the smallest total gains. + * Create a temporary array of the 'total gains' for each integration + * time. */ - time_idx = gts->num_itime - 1; - memcpy(all_gains, gains[time_idx], gain_bytes); - new_idx = gts->num_hwgain; + ret = iio_gts_alloc_int_table_array(&per_time_gains, gts->num_itime, + gts->num_hwgain); + if (ret) + return ret; - while (time_idx--) { - for (j = 0; j < gts->num_hwgain; j++) { - int candidate = gains[time_idx][j]; - int chk; + compute_per_time_gains(gts, per_time_gains); - if (candidate > all_gains[new_idx - 1]) { - all_gains[new_idx] = candidate; - new_idx++; + /* Convert the gains to scales and populate the scale tables */ + ret = fill_and_sort_scaletables(gts, per_time_gains, scales); - continue; - } - for (chk = 0; chk < new_idx; chk++) - if (candidate <= all_gains[chk]) - break; + iio_gts_free_int_table_array(per_time_gains, gts->num_itime); - if (candidate == all_gains[chk]) - continue; + return ret; +} - memmove(&all_gains[chk + 1], &all_gains[chk], - (new_idx - chk) * sizeof(int)); - all_gains[chk] = candidate; - new_idx++; - } - } +/* + * Create a table of supported scales for each supported integration time. + * This can be used as available_scales by drivers which don't allow scale + * setting to change the integration time to display correct set of scales + * depending on the used integration time. + */ +static int **create_per_time_scales(struct iio_gts *gts) +{ + int **per_time_scales, ret; - gts->avail_all_scales_table = kcalloc(new_idx, 2 * sizeof(int), - GFP_KERNEL); - if (!gts->avail_all_scales_table) { - ret = -ENOMEM; - goto free_out; - } - gts->num_avail_all_scales = new_idx; + ret = iio_gts_alloc_int_table_array(&per_time_scales, gts->num_itime, + gts->num_hwgain * 2); + if (ret) + return ERR_PTR(ret); - for (i = 0; i < gts->num_avail_all_scales; i++) { - ret = iio_gts_total_gain_to_scale(gts, all_gains[i], - >s->avail_all_scales_table[i * 2], - >s->avail_all_scales_table[i * 2 + 1]); + ret = compute_per_time_tables(gts, per_time_scales); + if (ret) + goto err_out; - if (ret) { - kfree(gts->avail_all_scales_table); - gts->num_avail_all_scales = 0; - goto free_out; - } - } + return per_time_scales; -free_out: - kfree(all_gains); +err_out: + iio_gts_free_int_table_array(per_time_scales, gts->num_itime); - return ret; + return ERR_PTR(ret); } /** @@ -275,53 +380,26 @@ free_out: */ static int iio_gts_build_avail_scale_table(struct iio_gts *gts) { - int **per_time_gains, **per_time_scales, i, j, ret = -ENOMEM; - - per_time_gains = kcalloc(gts->num_itime, sizeof(*per_time_gains), GFP_KERNEL); - if (!per_time_gains) - return ret; + int ret, all_scales_tbl_bytes; + int **per_time_scales; - per_time_scales = kcalloc(gts->num_itime, sizeof(*per_time_scales), GFP_KERNEL); - if (!per_time_scales) - goto free_gains; - - for (i = 0; i < gts->num_itime; i++) { - per_time_scales[i] = kcalloc(gts->num_hwgain, 2 * sizeof(int), - GFP_KERNEL); - if (!per_time_scales[i]) - goto err_free_out; - - per_time_gains[i] = kcalloc(gts->num_hwgain, sizeof(int), - GFP_KERNEL); - if (!per_time_gains[i]) { - kfree(per_time_scales[i]); - goto err_free_out; - } - - for (j = 0; j < gts->num_hwgain; j++) - per_time_gains[i][j] = gts->hwgain_table[j].gain * - gts->itime_table[i].mul; - } + if (unlikely(check_mul_overflow(gts->num_hwgain, 2 * sizeof(int), + &all_scales_tbl_bytes))) + return -EOVERFLOW; - ret = gain_to_scaletables(gts, per_time_gains, per_time_scales); - if (ret) - goto err_free_out; + per_time_scales = create_per_time_scales(gts); + if (IS_ERR(per_time_scales)) + return PTR_ERR(per_time_scales); - kfree(per_time_gains); gts->per_time_avail_scale_tables = per_time_scales; - return 0; - -err_free_out: - for (i--; i; i--) { - kfree(per_time_scales[i]); - kfree(per_time_gains[i]); + ret = do_combined_scaletable(gts, all_scales_tbl_bytes); + if (ret) { + iio_gts_free_int_table_array(per_time_scales, gts->num_itime); + return ret; } - kfree(per_time_scales); -free_gains: - kfree(per_time_gains); - return ret; + return 0; } static void iio_gts_us_to_int_micro(int *time_us, int *int_micro_times, @@ -362,17 +440,20 @@ static int iio_gts_build_avail_time_table(struct iio_gts *gts) for (i = gts->num_itime - 1; i >= 0; i--) { int new = gts->itime_table[i].time_us; - if (times[idx] < new) { + if (idx == 0 || times[idx - 1] < new) { times[idx++] = new; continue; } - for (j = 0; j <= idx; j++) { + for (j = 0; j < idx; j++) { + if (times[j] == new) + break; if (times[j] > new) { memmove(×[j + 1], ×[j], (idx - j) * sizeof(int)); times[j] = new; idx++; + break; } } } @@ -617,7 +698,7 @@ int devm_iio_init_iio_gts(struct device *dev, int max_scale_int, int max_scale_n return devm_iio_gts_build_avail_tables(dev, gts); } -EXPORT_SYMBOL_NS_GPL(devm_iio_init_iio_gts, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(devm_iio_init_iio_gts, "IIO_GTS_HELPER"); /** * iio_gts_all_avail_scales - helper for listing all available scales @@ -640,7 +721,7 @@ int iio_gts_all_avail_scales(struct iio_gts *gts, const int **vals, int *type, return IIO_AVAIL_LIST; } -EXPORT_SYMBOL_NS_GPL(iio_gts_all_avail_scales, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_all_avail_scales, "IIO_GTS_HELPER"); /** * iio_gts_avail_scales_for_time - list scales for integration time @@ -674,7 +755,7 @@ int iio_gts_avail_scales_for_time(struct iio_gts *gts, int time, return IIO_AVAIL_LIST; } -EXPORT_SYMBOL_NS_GPL(iio_gts_avail_scales_for_time, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_avail_scales_for_time, "IIO_GTS_HELPER"); /** * iio_gts_avail_times - helper for listing available integration times @@ -697,7 +778,7 @@ int iio_gts_avail_times(struct iio_gts *gts, const int **vals, int *type, return IIO_AVAIL_LIST; } -EXPORT_SYMBOL_NS_GPL(iio_gts_avail_times, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_avail_times, "IIO_GTS_HELPER"); /** * iio_gts_find_sel_by_gain - find selector corresponding to a HW-gain @@ -717,7 +798,7 @@ int iio_gts_find_sel_by_gain(struct iio_gts *gts, int gain) return -EINVAL; } -EXPORT_SYMBOL_NS_GPL(iio_gts_find_sel_by_gain, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_find_sel_by_gain, "IIO_GTS_HELPER"); /** * iio_gts_find_gain_by_sel - find HW-gain corresponding to a selector @@ -737,7 +818,7 @@ int iio_gts_find_gain_by_sel(struct iio_gts *gts, int sel) return -EINVAL; } -EXPORT_SYMBOL_NS_GPL(iio_gts_find_gain_by_sel, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_find_gain_by_sel, "IIO_GTS_HELPER"); /** * iio_gts_get_min_gain - find smallest valid HW-gain @@ -760,7 +841,7 @@ int iio_gts_get_min_gain(struct iio_gts *gts) return min; } -EXPORT_SYMBOL_NS_GPL(iio_gts_get_min_gain, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_get_min_gain, "IIO_GTS_HELPER"); /** * iio_find_closest_gain_low - Find the closest lower matching gain @@ -821,7 +902,7 @@ int iio_find_closest_gain_low(struct iio_gts *gts, int gain, bool *in_range) return gts->hwgain_table[best].gain; } -EXPORT_SYMBOL_NS_GPL(iio_find_closest_gain_low, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_find_closest_gain_low, "IIO_GTS_HELPER"); static int iio_gts_get_int_time_gain_multiplier_by_sel(struct iio_gts *gts, int sel) @@ -908,9 +989,52 @@ int iio_gts_find_gain_sel_for_scale_using_time(struct iio_gts *gts, int time_sel return 0; } -EXPORT_SYMBOL_NS_GPL(iio_gts_find_gain_sel_for_scale_using_time, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_find_gain_sel_for_scale_using_time, "IIO_GTS_HELPER"); + +/** + * iio_gts_find_gain_time_sel_for_scale - Fetch gain and time selectors for scale + * @gts: Gain time scale descriptor + * @scale_int: Integral part of the scale (typically val1) + * @scale_nano: Fractional part of the scale (nano or ppb) + * @gain_sel: Pointer to value where gain selector is stored. + * @time_sel: Pointer to value where time selector is stored. + * + * Wrapper around iio_gts_find_gain_for_scale_using_time() to fetch the + * gain and time selectors for a given scale. + * + * Return: 0 on success and -EINVAL on error. + */ +int iio_gts_find_gain_time_sel_for_scale(struct iio_gts *gts, int scale_int, + int scale_nano, int *gain_sel, + int *time_sel) +{ + int i, ret; + + for (i = 0; i < gts->num_itime; i++) { + *time_sel = gts->itime_table[i].sel; + ret = iio_gts_find_gain_sel_for_scale_using_time(gts, *time_sel, + scale_int, + scale_nano, + gain_sel); + if (ret) + continue; + + return 0; + } + + return -EINVAL; +} +EXPORT_SYMBOL_NS_GPL(iio_gts_find_gain_time_sel_for_scale, "IIO_GTS_HELPER"); -static int iio_gts_get_total_gain(struct iio_gts *gts, int gain, int time) +/** + * iio_gts_get_total_gain - Fetch total gain for given HW-gain and time + * @gts: Gain time scale descriptor + * @gain: HW-gain for which the total gain is searched for + * @time: Integration time for which the total gain is searched for + * + * Return: total gain on success and -EINVAL on error. + */ +int iio_gts_get_total_gain(struct iio_gts *gts, int gain, int time) { const struct iio_itime_sel_mul *itime; @@ -926,6 +1050,7 @@ static int iio_gts_get_total_gain(struct iio_gts *gts, int gain, int time) return gain * itime->mul; } +EXPORT_SYMBOL_NS_GPL(iio_gts_get_total_gain, "IIO_GTS_HELPER"); static int iio_gts_get_scale_linear(struct iio_gts *gts, int gain, int time, u64 *scale) @@ -970,7 +1095,7 @@ int iio_gts_get_scale(struct iio_gts *gts, int gain, int time, int *scale_int, return iio_gts_delinearize(lin_scale, NANO, scale_int, scale_nano); } -EXPORT_SYMBOL_NS_GPL(iio_gts_get_scale, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_get_scale, "IIO_GTS_HELPER"); /** * iio_gts_find_new_gain_sel_by_old_gain_time - compensate for time change @@ -1027,7 +1152,7 @@ int iio_gts_find_new_gain_sel_by_old_gain_time(struct iio_gts *gts, return 0; } -EXPORT_SYMBOL_NS_GPL(iio_gts_find_new_gain_sel_by_old_gain_time, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_find_new_gain_sel_by_old_gain_time, "IIO_GTS_HELPER"); /** * iio_gts_find_new_gain_by_old_gain_time - compensate for time change @@ -1079,7 +1204,49 @@ int iio_gts_find_new_gain_by_old_gain_time(struct iio_gts *gts, int old_gain, return 0; } -EXPORT_SYMBOL_NS_GPL(iio_gts_find_new_gain_by_old_gain_time, IIO_GTS_HELPER); +EXPORT_SYMBOL_NS_GPL(iio_gts_find_new_gain_by_old_gain_time, "IIO_GTS_HELPER"); + +/** + * iio_gts_find_new_gain_by_gain_time_min - compensate for time change + * @gts: Gain time scale descriptor + * @old_gain: Previously set gain + * @old_time: Selector corresponding previously set time + * @new_time: Selector corresponding new time to be set + * @new_gain: Pointer to value where new gain is to be written + * @in_range: Indicate if the @new_gain was in the range of + * supported gains. + * + * Wrapper around iio_gts_find_new_gain_by_old_gain_time() that tries to + * set an optimal value if no exact match was found, defaulting to the + * minimum gain to avoid saturations if the optimal value is not in the + * range of supported gains. + * + * Return: 0 on success and a negative value if no gain was found. + */ +int iio_gts_find_new_gain_by_gain_time_min(struct iio_gts *gts, int old_gain, + int old_time, int new_time, + int *new_gain, bool *in_range) +{ + int ret; + + *in_range = true; + ret = iio_gts_find_new_gain_by_old_gain_time(gts, old_gain, old_time, + new_time, new_gain); + if (*new_gain < 0) + return -EINVAL; + + if (ret) { + *new_gain = iio_find_closest_gain_low(gts, *new_gain, in_range); + if (*new_gain < 0) { + *new_gain = iio_gts_get_min_gain(gts); + if (*new_gain < 0) + return -EINVAL; + } + } + + return 0; +} +EXPORT_SYMBOL_NS_GPL(iio_gts_find_new_gain_by_gain_time_min, "IIO_GTS_HELPER"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Matti Vaittinen <mazziesaccount@gmail.com>"); |