The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x d5078509c8b06c5c472a60232815e41af81c6446 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2024012629-unrobed-other-c41a@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^.. Possible dependencies: d5078509c8b0 ("serial: sc16is7xx: improve do/while loop in sc16is7xx_irq()") 4409df5866b7 ("serial: sc16is7xx: change EFR lock to operate on each channels") 3837a0379533 ("serial: sc16is7xx: improve regmap debugfs by using one regmap per port") b4a778303ea0 ("serial: sc16is7xx: add missing support for rs485 devicetree properties") 049994292834 ("serial: sc16is7xx: fix regression with GPIO configuration") dabc54a45711 ("serial: sc16is7xx: remove obsolete out_thread label") c8f71b49ee4d ("serial: sc16is7xx: setup GPIO controller later in probe") 267913ecf737 ("serial: sc16is7xx: Fill in rs485_supported") 21144bab4f11 ("sc16is7xx: Handle modem status lines") cc4c1d05eb10 ("sc16is7xx: Properly resume TX after stop") d4ab5487cc77 ("Merge 5.17-rc6 into tty-next") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From d5078509c8b06c5c472a60232815e41af81c6446 Mon Sep 17 00:00:00 2001 From: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx> Date: Thu, 21 Dec 2023 18:18:12 -0500 Subject: [PATCH] serial: sc16is7xx: improve do/while loop in sc16is7xx_irq() Simplify and improve readability by replacing while(1) loop with do {} while, and by using the keep_polling variable as the exit condition, making it more explicit. Fixes: 834449872105 ("sc16is7xx: Fix for multi-channel stall") Cc: <stable@xxxxxxxxxxxxxxx> Suggested-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> Signed-off-by: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20231221231823.2327894-6-hugo@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index 44a11c89c949..8d257208cbf3 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -783,17 +783,18 @@ static bool sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno) static irqreturn_t sc16is7xx_irq(int irq, void *dev_id) { + bool keep_polling; + struct sc16is7xx_port *s = (struct sc16is7xx_port *)dev_id; - while (1) { - bool keep_polling = false; + do { int i; + keep_polling = false; + for (i = 0; i < s->devtype->nr_uart; ++i) keep_polling |= sc16is7xx_port_irq(s, i); - if (!keep_polling) - break; - } + } while (keep_polling); return IRQ_HANDLED; }
