This is a note to let you know that I've just added the patch titled
iio: adc: stm32: fix stm32h7_adc_enable error handling
to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: iio-adc-stm32-fix-stm32h7_adc_enable-error-handling.patch and it can be found in the queue-4.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From a3b5655ebdb501a98a45c0d3265dca9f2fe0218a Mon Sep 17 00:00:00 2001
From: Fabrice Gasnier fabrice.gasnier@st.com Date: Tue, 23 Jan 2018 17:04:56 +0100 Subject: iio: adc: stm32: fix stm32h7_adc_enable error handling
From: Fabrice Gasnier fabrice.gasnier@st.com
commit a3b5655ebdb501a98a45c0d3265dca9f2fe0218a upstream.
Error handling in stm32h7_adc_enable routine doesn't unwind enable sequence correctly. ADEN can only be cleared by hardware (e.g. by writing one to ADDIS). It's also better to clear ADRDY just after it's been set by hardware.
Fixes: 95e339b6e85d ("iio: adc: stm32: add support for STM32H7")
Signed-off-by: Fabrice Gasnier fabrice.gasnier@st.com Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/iio/adc/stm32-adc.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
--- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -765,8 +765,6 @@ static int stm32h7_adc_enable(struct stm int ret; u32 val;
- /* Clear ADRDY by writing one, then enable ADC */ - stm32_adc_set_bits(adc, STM32H7_ADC_ISR, STM32H7_ADRDY); stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADEN);
/* Poll for ADRDY to be set (after adc startup time) */ @@ -774,8 +772,11 @@ static int stm32h7_adc_enable(struct stm val & STM32H7_ADRDY, 100, STM32_ADC_TIMEOUT_US); if (ret) { - stm32_adc_clr_bits(adc, STM32H7_ADC_CR, STM32H7_ADEN); + stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADDIS); dev_err(&indio_dev->dev, "Failed to enable ADC\n"); + } else { + /* Clear ADRDY by writing one */ + stm32_adc_set_bits(adc, STM32H7_ADC_ISR, STM32H7_ADRDY); }
return ret;
Patches currently in stable-queue which might be from fabrice.gasnier@st.com are
queue-4.15/iio-adc-stm32-fix-stm32h7_adc_enable-error-handling.patch