@@ -103,7 +103,7 @@ static const unsigned long long freq_range_lpf[4][2] = {
{2050000000ULL, 3850000000ULL},
{3350000000ULL, 7250000000ULL},
{7000000000, 13000000000},
- {12550000000, 18500000000}
+ {12550000000, 18850000000}
};
static const struct regmap_config admv8818_regmap_config = {
@@ -122,43 +122,59 @@ static const char * const admv8818_modes[] = {
static int __admv8818_hpf_select(struct admv8818_state *st, u64 freq)
{
unsigned int hpf_step = 0, hpf_band = 0, i, j;
+ u64 freq_error;
+ u64 min_freq_error;
+ u64 freq_corner;
u64 freq_step;
int ret;
if (freq < freq_range_hpf[0][0])
goto hpf_write;
- if (freq > freq_range_hpf[3][1]) {
+ if (freq >= freq_range_hpf[3][1]) {
hpf_step = 15;
hpf_band = 4;
goto hpf_write;
}
+ /* Close HPF frequency gap between 12 and 12.5 GHz */
+ if (freq >= 12000 * HZ_PER_MHZ && freq < 12500 * HZ_PER_MHZ) {
+ hpf_step = 15;
+ hpf_band = 3;
+
+ goto hpf_write;
+ }
+
+ min_freq_error = U64_MAX;
for (i = 0; i < 4; i++) {
+ /* This (and therefore all other ranges) have a corner
+ * frequency higher than the target frequency.
+ */
+ if (freq_range_hpf[i][0] > freq)
+ break;
+
freq_step = div_u64((freq_range_hpf[i][1] -
freq_range_hpf[i][0]), 15);
- if (freq > freq_range_hpf[i][0] &&
- (freq < freq_range_hpf[i][1] + freq_step)) {
- hpf_band = i + 1;
+ for (j = 0; j <= 15; j++) {
+ freq_corner = freq_range_hpf[i][0] + (freq_step * j);
- for (j = 1; j <= 16; j++) {
- if (freq < (freq_range_hpf[i][0] + (freq_step * j))) {
- hpf_step = j - 1;
- break;
- }
+ /* This (and therefore all other steps) have a corner
+ * frequency higher than the target frequency.
+ */
+ if (freq_corner > freq)
+ break;
+
+ freq_error = freq - freq_corner;
+ if (freq_error < min_freq_error) {
+ min_freq_error = freq_error;
+ hpf_step = j;
+ hpf_band = i + 1;
}
- break;
}
}
- /* Close HPF frequency gap between 12 and 12.5 GHz */
- if (freq >= 12000 * HZ_PER_MHZ && freq <= 12500 * HZ_PER_MHZ) {
- hpf_band = 3;
- hpf_step = 15;
- }
-
hpf_write:
ret = regmap_update_bits(st->regmap, ADMV8818_REG_WR0_SW,
ADMV8818_SW_IN_SET_WR0_MSK |
@@ -186,7 +202,11 @@ static int admv8818_hpf_select(struct admv8818_state *st, u64 freq)
static int __admv8818_lpf_select(struct admv8818_state *st, u64 freq)
{
- unsigned int lpf_step = 0, lpf_band = 0, i, j;
+ int i, j;
+ unsigned int lpf_step = 0, lpf_band = 0;
+ u64 freq_error;
+ u64 min_freq_error;
+ u64 freq_corner;
u64 freq_step;
int ret;
@@ -199,18 +219,34 @@ static int __admv8818_lpf_select(struct admv8818_state *st, u64 freq)
goto lpf_write;
}
- for (i = 0; i < 4; i++) {
- if (freq > freq_range_lpf[i][0] && freq < freq_range_lpf[i][1]) {
- lpf_band = i + 1;
- freq_step = div_u64((freq_range_lpf[i][1] - freq_range_lpf[i][0]), 15);
-
- for (j = 0; j <= 15; j++) {
- if (freq < (freq_range_lpf[i][0] + (freq_step * j))) {
- lpf_step = j;
- break;
- }
- }
+ min_freq_error = U64_MAX;
+ for (i = 3; i >= 0; --i) {
+ /* At this point the highest corner frequency of
+ * all remaining ranges is below the target.
+ * LPF corner should be >= the target.
+ */
+ if (freq > freq_range_lpf[i][1])
break;
+
+ freq_step = div_u64((freq_range_lpf[i][1] - freq_range_lpf[i][0]), 15);
+
+ for (j = 15; j >= 0; --j) {
+
+ freq_corner = freq_range_lpf[i][0] + j*freq_step;
+
+ /* At this point all other steps in range will
+ * place the corner frequency below the target
+ * LPF corner should >= the target.
+ */
+ if (freq > freq_corner)
+ break;
+
+ freq_error = freq_corner - freq;
+ if (freq_error < min_freq_error) {
+ min_freq_error = freq_error;
+ lpf_step = j;
+ lpf_band = i + 1;
+ }
}
}
Corrects the upper range of LPF Band 4 from 18.5 GHz to 18.85 GHz per the ADMV8818 datasheet Search for the minimum error while ensuring that the LPF corner frequency is greater than the target, and the HPF corner frequency is lower than the target This fixes issues where the range calculations were suboptimal. Below is a generated table (10 MHz resolution) === HPF === freq = 1750 MHz, 3db: bypass => 1750 MHz freq = 3400 MHz, 3db: 3310 => 3400 MHz freq = 3410 MHz, 3db: 3310 => 3400 MHz freq = 3420 MHz, 3db: 3310 => 3400 MHz freq = 3660 MHz, 3db: 3550 => 3656 MHz freq = 6600 MHz, 3db: 6479 => 6600 MHz freq = 6610 MHz, 3db: 6479 => 6600 MHz freq = 6620 MHz, 3db: 6479 => 6600 MHz freq = 6630 MHz, 3db: 6479 => 6600 MHz freq = 6640 MHz, 3db: 6479 => 6600 MHz freq = 6650 MHz, 3db: 6479 => 6600 MHz freq = 6660 MHz, 3db: 6479 => 6600 MHz freq = 6670 MHz, 3db: 6479 => 6600 MHz freq = 6680 MHz, 3db: 6479 => 6600 MHz freq = 6690 MHz, 3db: 6479 => 6600 MHz freq = 6700 MHz, 3db: 6479 => 6600 MHz freq = 6710 MHz, 3db: 6479 => 6600 MHz freq = 6720 MHz, 3db: 6479 => 6600 MHz freq = 6730 MHz, 3db: 6479 => 6600 MHz freq = 6960 MHz, 3db: 6736 => 6960 MHz freq = 6970 MHz, 3db: 6736 => 6960 MHz freq = 6980 MHz, 3db: 6736 => 6960 MHz freq = 6990 MHz, 3db: 6736 => 6960 MHz freq = 7320 MHz, 3db: 7249 => 7320 MHz freq = 7330 MHz, 3db: 7249 => 7320 MHz freq = 7340 MHz, 3db: 7249 => 7320 MHz freq = 7350 MHz, 3db: 7249 => 7320 MHz freq = 7360 MHz, 3db: 7249 => 7320 MHz freq = 7370 MHz, 3db: 7249 => 7320 MHz freq = 7380 MHz, 3db: 7249 => 7320 MHz freq = 7390 MHz, 3db: 7249 => 7320 MHz freq = 7400 MHz, 3db: 7249 => 7320 MHz freq = 7410 MHz, 3db: 7249 => 7320 MHz freq = 7420 MHz, 3db: 7249 => 7320 MHz freq = 7430 MHz, 3db: 7249 => 7320 MHz freq = 7440 MHz, 3db: 7249 => 7320 MHz freq = 7450 MHz, 3db: 7249 => 7320 MHz freq = 7460 MHz, 3db: 7249 => 7320 MHz freq = 7470 MHz, 3db: 7249 => 7320 MHz freq = 7480 MHz, 3db: 7249 => 7320 MHz freq = 7490 MHz, 3db: 7249 => 7320 MHz freq = 7500 MHz, 3db: 7249 => 7320 MHz freq = 12500 MHz, 3db: 12000 => 12500 MHz === LPF === freq = 2050 MHz, 3db: bypass => 2050 MHz freq = 2170 MHz, 3db: 2290 => 2170 MHz freq = 2290 MHz, 3db: 2410 => 2290 MHz freq = 2410 MHz, 3db: 2530 => 2410 MHz freq = 2530 MHz, 3db: 2650 => 2530 MHz freq = 2650 MHz, 3db: 2770 => 2650 MHz freq = 2770 MHz, 3db: 2890 => 2770 MHz freq = 2890 MHz, 3db: 3010 => 2890 MHz freq = 3010 MHz, 3db: 3130 => 3010 MHz freq = 3130 MHz, 3db: 3250 => 3130 MHz freq = 3250 MHz, 3db: 3370 => 3250 MHz freq = 3260 MHz, 3db: 3370 => 3350 MHz freq = 3270 MHz, 3db: 3370 => 3350 MHz freq = 3280 MHz, 3db: 3370 => 3350 MHz freq = 3290 MHz, 3db: 3370 => 3350 MHz freq = 3300 MHz, 3db: 3370 => 3350 MHz freq = 3310 MHz, 3db: 3370 => 3350 MHz freq = 3320 MHz, 3db: 3370 => 3350 MHz freq = 3330 MHz, 3db: 3370 => 3350 MHz freq = 3340 MHz, 3db: 3370 => 3350 MHz freq = 3350 MHz, 3db: 3370 => 3350 MHz freq = 3370 MHz, 3db: 3490 => 3370 MHz freq = 3490 MHz, 3db: 3610 => 3490 MHz freq = 3610 MHz, 3db: 3730 => 3610 MHz freq = 3730 MHz, 3db: 3850 => 3730 MHz freq = 3850 MHz, 3db: 3870 => 3850 MHz freq = 3870 MHz, 3db: 4130 => 3870 MHz freq = 4130 MHz, 3db: 4390 => 4130 MHz freq = 4390 MHz, 3db: 4650 => 4390 MHz freq = 4650 MHz, 3db: 4910 => 4650 MHz freq = 4910 MHz, 3db: 5170 => 4910 MHz freq = 5170 MHz, 3db: 5430 => 5170 MHz freq = 5430 MHz, 3db: 5690 => 5430 MHz freq = 5690 MHz, 3db: 5950 => 5690 MHz freq = 5950 MHz, 3db: 6210 => 5950 MHz freq = 6210 MHz, 3db: 6470 => 6210 MHz freq = 6470 MHz, 3db: 6730 => 6470 MHz freq = 6730 MHz, 3db: 6990 => 6730 MHz freq = 6990 MHz, 3db: 7250 => 6990 MHz freq = 7000 MHz, 3db: 7250 => 7000 MHz freq = 7250 MHz, 3db: 7400 => 7250 MHz freq = 7400 MHz, 3db: 7800 => 7400 MHz freq = 7800 MHz, 3db: 8200 => 7800 MHz freq = 8200 MHz, 3db: 8600 => 8200 MHz freq = 8600 MHz, 3db: 9000 => 8600 MHz freq = 9000 MHz, 3db: 9400 => 9000 MHz freq = 9400 MHz, 3db: 9800 => 9400 MHz freq = 9800 MHz, 3db: 10200 => 9800 MHz freq = 10200 MHz, 3db: 10600 => 10200 MHz freq = 10600 MHz, 3db: 11000 => 10600 MHz freq = 11000 MHz, 3db: 11400 => 11000 MHz freq = 11400 MHz, 3db: 11800 => 11400 MHz freq = 11800 MHz, 3db: 12200 => 11800 MHz freq = 12200 MHz, 3db: 12600 => 12200 MHz freq = 12210 MHz, 3db: 12600 => 12550 MHz freq = 12220 MHz, 3db: 12600 => 12550 MHz freq = 12230 MHz, 3db: 12600 => 12550 MHz freq = 12240 MHz, 3db: 12600 => 12550 MHz freq = 12250 MHz, 3db: 12600 => 12550 MHz freq = 12260 MHz, 3db: 12600 => 12550 MHz freq = 12270 MHz, 3db: 12600 => 12550 MHz freq = 12280 MHz, 3db: 12600 => 12550 MHz freq = 12290 MHz, 3db: 12600 => 12550 MHz freq = 12300 MHz, 3db: 12600 => 12550 MHz freq = 12310 MHz, 3db: 12600 => 12550 MHz freq = 12320 MHz, 3db: 12600 => 12550 MHz freq = 12330 MHz, 3db: 12600 => 12550 MHz freq = 12340 MHz, 3db: 12600 => 12550 MHz freq = 12350 MHz, 3db: 12600 => 12550 MHz freq = 12360 MHz, 3db: 12600 => 12550 MHz freq = 12370 MHz, 3db: 12600 => 12550 MHz freq = 12380 MHz, 3db: 12600 => 12550 MHz freq = 12390 MHz, 3db: 12600 => 12550 MHz freq = 12400 MHz, 3db: 12600 => 12550 MHz freq = 12410 MHz, 3db: 12600 => 12550 MHz freq = 12420 MHz, 3db: 12600 => 12550 MHz freq = 12430 MHz, 3db: 12600 => 12550 MHz freq = 12440 MHz, 3db: 12600 => 12550 MHz freq = 12450 MHz, 3db: 12600 => 12550 MHz freq = 12460 MHz, 3db: 12600 => 12550 MHz freq = 12470 MHz, 3db: 12600 => 12550 MHz freq = 12480 MHz, 3db: 12600 => 12550 MHz freq = 12490 MHz, 3db: 12600 => 12550 MHz freq = 12500 MHz, 3db: 12600 => 12550 MHz freq = 12510 MHz, 3db: 12600 => 12550 MHz freq = 12520 MHz, 3db: 12600 => 12550 MHz freq = 12530 MHz, 3db: 12600 => 12550 MHz freq = 12540 MHz, 3db: 12600 => 12550 MHz freq = 12550 MHz, 3db: 12600 => 12550 MHz freq = 12600 MHz, 3db: 13000 => 12600 MHz freq = 12610 MHz, 3db: 13000 => 12970 MHz freq = 12620 MHz, 3db: 13000 => 12970 MHz freq = 12630 MHz, 3db: 13000 => 12970 MHz freq = 12640 MHz, 3db: 13000 => 12970 MHz freq = 12650 MHz, 3db: 13000 => 12970 MHz freq = 12660 MHz, 3db: 13000 => 12970 MHz freq = 12670 MHz, 3db: 13000 => 12970 MHz freq = 12680 MHz, 3db: 13000 => 12970 MHz freq = 12690 MHz, 3db: 13000 => 12970 MHz freq = 12700 MHz, 3db: 13000 => 12970 MHz freq = 12710 MHz, 3db: 13000 => 12970 MHz freq = 12720 MHz, 3db: 13000 => 12970 MHz freq = 12730 MHz, 3db: 13000 => 12970 MHz freq = 12740 MHz, 3db: 13000 => 12970 MHz freq = 12750 MHz, 3db: 13000 => 12970 MHz freq = 12760 MHz, 3db: 13000 => 12970 MHz freq = 12770 MHz, 3db: 13000 => 12970 MHz freq = 12780 MHz, 3db: 13000 => 12970 MHz freq = 12790 MHz, 3db: 13000 => 12970 MHz freq = 12800 MHz, 3db: 13000 => 12970 MHz freq = 12810 MHz, 3db: 13000 => 12970 MHz freq = 12820 MHz, 3db: 13000 => 12970 MHz freq = 12830 MHz, 3db: 13000 => 12970 MHz freq = 12840 MHz, 3db: 13000 => 12970 MHz freq = 12850 MHz, 3db: 13000 => 12970 MHz freq = 12860 MHz, 3db: 13000 => 12970 MHz freq = 12870 MHz, 3db: 13000 => 12970 MHz freq = 12880 MHz, 3db: 13000 => 12970 MHz freq = 12890 MHz, 3db: 13000 => 12970 MHz freq = 12900 MHz, 3db: 13000 => 12970 MHz freq = 12910 MHz, 3db: 13000 => 12970 MHz freq = 12920 MHz, 3db: 13000 => 12970 MHz freq = 12930 MHz, 3db: 13000 => 12970 MHz freq = 12940 MHz, 3db: 13000 => 12970 MHz freq = 12950 MHz, 3db: 13000 => 12970 MHz freq = 12960 MHz, 3db: 13000 => 12970 MHz freq = 12970 MHz, 3db: 13000 => 12970 MHz freq = 13000 MHz, 3db: 13390 => 13000 MHz freq = 13390 MHz, 3db: 13810 => 13390 MHz freq = 13810 MHz, 3db: 14230 => 13810 MHz freq = 14230 MHz, 3db: 14650 => 14230 MHz freq = 14650 MHz, 3db: 15070 => 14650 MHz freq = 15070 MHz, 3db: 15490 => 15070 MHz freq = 15490 MHz, 3db: 15910 => 15490 MHz freq = 15910 MHz, 3db: 16330 => 15910 MHz freq = 16330 MHz, 3db: 16750 => 16330 MHz freq = 16750 MHz, 3db: 17170 => 16750 MHz freq = 17170 MHz, 3db: 17590 => 17170 MHz freq = 17590 MHz, 3db: 18010 => 17590 MHz freq = 18010 MHz, 3db: 18430 => 18010 MHz freq = 18430 MHz, 3db: 18850 => 18430 MHz freq = 18850 MHz, 3db: bypass => 18850 MHz Fixes: f34fe888ad05 ("iio:filter:admv8818: add support for ADMV8818") Signed-off-by: Sam Winchenbach <swinchenbach@arka.org> Signed-off-by: Sam Winchenbach <sam.winchenbach@framepointer.org> --- drivers/iio/filter/admv8818.c | 94 ++++++++++++++++++++++++----------- 1 file changed, 65 insertions(+), 29 deletions(-)