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charset="utf-8" Content-Transfer-Encoding: quoted-printable X-ADIRuleOP-NewSCL: Rule Triggered X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNjA0MDE1NSBTYWx0ZWRfX02aSiB/grcK/ jXQKojBz6iaxqZFwbRVmfmltsn5ga62Ev8EZKZVYZG7GJMZDTd6AXqwIb9ptqWYPukzMMjQsbI6 MJ5yIaeVql/SllvVHcUmo4u7L6yOSD3r9aUI7Ta7QvQnwga+2RN3rYVYj6m44/QPm+9zyvnl8vi nIRI2khkNvHOsy3kJ/TP+VlMYJQcH2WaUHc7ei833ANTBlLzyz91fEJWQ/CGp/k/gYdYT7dpgBa vkHEjKHg7cIXFgwntWZTcnwFJ6TtjgnqYvS5/V5P/96+kIcgxjbmDjq/GnmsdHQSJG6ooupDpkb g+vvAU15NndviC8aaUwO9bKDaZv05z4zUqyG7YlU9NCSG5clA8uaZ8fhnH0hQ/3BuEK7vKruwRB cF4E5Qy3UrS4BWRoeYhB7A63iNdnT32cjsoA9QBD3eTT1iyCf/FWsCgXVkebrPtujxPEs5ci X-Proofpoint-GUID: -0gOjBYSoDnGXILWY2UVDpY-jZI98bOH X-Proofpoint-ORIG-GUID: -0gOjBYSoDnGXILWY2UVDpY-jZI98bOH X-Authority-Analysis: v=2.4 cv=CdgI5Krl c=1 sm=1 tr=0 ts=6840a00c cx=c_pps a=PpDZqlmH/M8setHirZLBMw==:117 a=PpDZqlmH/M8setHirZLBMw==:17 a=IkcTkHD0fZMA:10 a=6IFa9wvqVegA:10 a=gAnH3GRIAAAA:8 a=vwO0T6k6XbGL632noZEA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1099,Hydra:6.0.736,FMLib:17.12.80.40 definitions=2025-06-04_04,2025-06-03_02,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 bulkscore=0 lowpriorityscore=0 impostorscore=0 clxscore=1015 mlxscore=0 adultscore=0 phishscore=0 mlxlogscore=999 spamscore=0 suspectscore=0 malwarescore=0 classifier=spam authscore=0 authtc=n/a authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2505280000 definitions=main-2506040155 The SYNC_IN pulse width must be at least 1.5 x Tmclk, corresponding to ~2.5 =C2=B5s at the lowest supported MCLK frequency. Add a 3 =C2=B5s delay = to ensure reliable synchronization timing even for the worst-case scenario. Signed-off-by: Jonathan Santos Reviewed-by: David Lechner --- v10 Changes: * New patch. --- drivers/iio/adc/ad7768-1.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/drivers/iio/adc/ad7768-1.c b/drivers/iio/adc/ad7768-1.c index 51134023534a..8b414a102864 100644 --- a/drivers/iio/adc/ad7768-1.c +++ b/drivers/iio/adc/ad7768-1.c @@ -252,6 +252,24 @@ static const struct regmap_config ad7768_regmap24_conf= ig =3D { .max_register =3D AD7768_REG24_COEFF_DATA, }; =20 +static int ad7768_send_sync_pulse(struct ad7768_state *st) +{ + /* + * The datasheet specifies a minimum SYNC_IN pulse width of 1.5 =C3=97 Tm= clk, + * where Tmclk is the MCLK period. The supported MCLK frequencies range + * from 0.6 MHz to 17 MHz, which corresponds to a minimum SYNC_IN pulse + * width of approximately 2.5 =C2=B5s in the worst-case scenario (0.6 MHz= ). + * + * Add a delay to ensure the pulse width is always sufficient to + * trigger synchronization. + */ + gpiod_set_value_cansleep(st->gpio_sync_in, 1); + fsleep(3); + gpiod_set_value_cansleep(st->gpio_sync_in, 0); + + return 0; +} + static int ad7768_set_mode(struct ad7768_state *st, enum ad7768_conv_mode mode) { @@ -339,10 +357,7 @@ static int ad7768_set_dig_fil(struct ad7768_state *st, return ret; =20 /* A sync-in pulse is required every time the filter dec rate changes */ - gpiod_set_value(st->gpio_sync_in, 1); - gpiod_set_value(st->gpio_sync_in, 0); - - return 0; + return ad7768_send_sync_pulse(st); } =20 static int ad7768_set_freq(struct ad7768_state *st, --=20 2.34.1