From 1a772719318c11e146f6fbe621fffd230a6f456a Mon Sep 17 00:00:00 2001 From: Radu Sabau Date: Wed, 8 Apr 2026 13:32:13 +0300 Subject: [PATCH] iio: adc: ad4695: Fix call ordering in offload buffer postenable MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ad4695_enter_advanced_sequencer_mode() was called after spi_offload_trigger_enable(). That is wrong because ad4695_enter_advanced_sequencer_mode() issues regular SPI transfers to put the ADC into advanced sequencer mode, and not all SPI offload capable controllers support regular SPI transfers while offloading is enabled. Fix this by calling ad4695_enter_advanced_sequencer_mode() before spi_offload_trigger_enable(), so the ADC is fully configured before the first CNV pulse can occur. This is consistent with the same constraint that already applies to the BUSY_GP_EN write above it. Update the error unwind labels accordingly: add err_exit_conversion_mode so that a failure of spi_offload_trigger_enable() correctly exits conversion mode before clearing BUSY_GP_EN. Fixes: f09f140e3ea8 ("iio: adc: ad4695: Add support for SPI offload") Reviewed-by: Nuno Sá Reviewed-by: David Lechner Signed-off-by: Radu Sabau Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron --- drivers/iio/adc/ad4695.c | 23 ++++++++--------------- 1 file changed, 8 insertions(+), 15 deletions(-) diff --git a/drivers/iio/adc/ad4695.c b/drivers/iio/adc/ad4695.c index cda419638d9a..53642de7330d 100644 --- a/drivers/iio/adc/ad4695.c +++ b/drivers/iio/adc/ad4695.c @@ -876,14 +876,14 @@ static int ad4695_offload_buffer_postenable(struct iio_dev *indio_dev) if (ret) goto err_unoptimize_message; - ret = spi_offload_trigger_enable(st->offload, st->offload_trigger, - &config); + ret = ad4695_enter_advanced_sequencer_mode(st, num_slots); if (ret) goto err_disable_busy_output; - ret = ad4695_enter_advanced_sequencer_mode(st, num_slots); + ret = spi_offload_trigger_enable(st->offload, st->offload_trigger, + &config); if (ret) - goto err_offload_trigger_disable; + goto err_exit_conversion_mode; mutex_lock(&st->cnv_pwm_lock); pwm_get_state(st->cnv_pwm, &state); @@ -895,23 +895,16 @@ static int ad4695_offload_buffer_postenable(struct iio_dev *indio_dev) ret = pwm_apply_might_sleep(st->cnv_pwm, &state); mutex_unlock(&st->cnv_pwm_lock); if (ret) - goto err_offload_exit_conversion_mode; + goto err_offload_trigger_disable; return 0; -err_offload_exit_conversion_mode: - /* - * We have to unwind in a different order to avoid triggering offload. - * ad4695_exit_conversion_mode() triggers a conversion, so it has to be - * done after spi_offload_trigger_disable(). - */ - spi_offload_trigger_disable(st->offload, st->offload_trigger); - ad4695_exit_conversion_mode(st); - goto err_disable_busy_output; - err_offload_trigger_disable: spi_offload_trigger_disable(st->offload, st->offload_trigger); +err_exit_conversion_mode: + ad4695_exit_conversion_mode(st); + err_disable_busy_output: regmap_clear_bits(st->regmap, AD4695_REG_GP_MODE, AD4695_REG_GP_MODE_BUSY_GP_EN);