5.15-stable review patch. If anyone has any objections, please let me know.
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From: Lino Sanfilippo l.sanfilippo@kunbus.com
[ Upstream commit 885dcb08c93d75b784468e65fd4f1f82d5313061 ]
Currently the documentation claims that a maximum of 1000 msecs is allowed for RTS delays. However nothing actually checks the values read from device tree/ACPI and so it is possible to set much higher values.
There is already a maximum of 100 ms enforced for RTS delays that are set via the UART TIOCSRS485 ioctl. To be consistent with that use the same limit for DT/ACPI values.
Although this change is visible to userspace the risk of breaking anything when reducing the max delays from 1000 to 100 ms should be very low, since 100 ms is already a very high maximum for delays that are usually rather in the usecs range.
Acked-by: Rob Herring robh@kernel.org Signed-off-by: Lino Sanfilippo l.sanfilippo@kunbus.com Link: https://lore.kernel.org/r/20220710164442.2958979-7-LinoSanfilippo@gmx.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Stable-dep-of: 12b3642b6c24 ("dt-bindings: serial: rs485: Fix rs485-rts-delay property") Signed-off-by: Sasha Levin sashal@kernel.org --- Documentation/devicetree/bindings/serial/rs485.yaml | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/devicetree/bindings/serial/rs485.yaml b/Documentation/devicetree/bindings/serial/rs485.yaml index 0c9fa694f85c8..518949737c86e 100644 --- a/Documentation/devicetree/bindings/serial/rs485.yaml +++ b/Documentation/devicetree/bindings/serial/rs485.yaml @@ -22,12 +22,12 @@ properties: - description: Delay between rts signal and beginning of data sent in milliseconds. It corresponds to the delay before sending data. default: 0 - maximum: 1000 + maximum: 100 - description: Delay between end of data sent and rts signal in milliseconds. It corresponds to the delay after sending data and actual release of the line. default: 0 - maximum: 1000 + maximum: 100
rs485-rts-active-low: description: drive RTS low when sending (default is high).