This is a note to let you know that I've just added the patch titled regmap-irq: Update interrupt clear register for proper reset to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: regmap-irq-update-interrupt-clear-register-for-prope.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 239f2244b493da50a811d97cfff0978b0098d3ea Author: Prasad Kumpatla <quic_pkumpatl@xxxxxxxxxxx> Date: Thu Feb 17 14:20:07 2022 +0530 regmap-irq: Update interrupt clear register for proper reset [ Upstream commit d04ad245d67a3991dfea5e108e4c452c2ab39bac ] With the existing logic where clear_ack is true (HW doesn’t support auto clear for ICR), interrupt clear register reset is not handled properly. Due to this only the first interrupts get processed properly and further interrupts are blocked due to not resetting interrupt clear register. Example for issue case where Invert_ack is false and clear_ack is true: Say Default ISR=0x00 & ICR=0x00 and ISR is triggered with 2 interrupts making ISR = 0x11. Step 1: Say ISR is set 0x11 (store status_buff = ISR). ISR needs to be cleared with the help of ICR once the Interrupt is processed. Step 2: Write ICR = 0x11 (status_buff), this will clear the ISR to 0x00. Step 3: Issue - In the existing code, ICR is written with ICR = ~(status_buff) i.e ICR = 0xEE -> This will block all the interrupts from raising except for interrupts 0 and 4. So expectation here is to reset ICR, which will unblock all the interrupts. if (chip->clear_ack) { if (chip->ack_invert && !ret) ........ else if (!ret) ret = regmap_write(map, reg, ~data->status_buf[i]); So writing 0 and 0xff (when ack_invert is true) should have no effect, other than clearing the ACKs just set. Fixes: 3a6f0fb7b8eb ("regmap: irq: Add support to clear ack registers") Signed-off-by: Prasad Kumpatla <quic_pkumpatl@xxxxxxxxxxx> Reviewed-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20220217085007.30218-1-quic_pkumpatl@xxxxxxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c index d2656581a6085..4a446259a184e 100644 --- a/drivers/base/regmap/regmap-irq.c +++ b/drivers/base/regmap/regmap-irq.c @@ -189,11 +189,9 @@ static void regmap_irq_sync_unlock(struct irq_data *data) ret = regmap_write(map, reg, d->mask_buf[i]); if (d->chip->clear_ack) { if (d->chip->ack_invert && !ret) - ret = regmap_write(map, reg, - d->mask_buf[i]); + ret = regmap_write(map, reg, UINT_MAX); else if (!ret) - ret = regmap_write(map, reg, - ~d->mask_buf[i]); + ret = regmap_write(map, reg, 0); } if (ret != 0) dev_err(d->map->dev, "Failed to ack 0x%x: %d\n", @@ -556,11 +554,9 @@ static irqreturn_t regmap_irq_thread(int irq, void *d) data->status_buf[i]); if (chip->clear_ack) { if (chip->ack_invert && !ret) - ret = regmap_write(map, reg, - data->status_buf[i]); + ret = regmap_write(map, reg, UINT_MAX); else if (!ret) - ret = regmap_write(map, reg, - ~data->status_buf[i]); + ret = regmap_write(map, reg, 0); } if (ret != 0) dev_err(map->dev, "Failed to ack 0x%x: %d\n", @@ -817,13 +813,9 @@ int regmap_add_irq_chip_fwnode(struct fwnode_handle *fwnode, d->status_buf[i] & d->mask_buf[i]); if (chip->clear_ack) { if (chip->ack_invert && !ret) - ret = regmap_write(map, reg, - (d->status_buf[i] & - d->mask_buf[i])); + ret = regmap_write(map, reg, UINT_MAX); else if (!ret) - ret = regmap_write(map, reg, - ~(d->status_buf[i] & - d->mask_buf[i])); + ret = regmap_write(map, reg, 0); } if (ret != 0) { dev_err(map->dev, "Failed to ack 0x%x: %d\n",