interconnect: mediatek: Aggregate bandwidth with saturating add

By using a regular non-overflow-checking add, the MediaTek icc-emi
driver will happy wrap at U32_MAX + 1 to 0. As it's common for the

interconnect: mediatek: Aggregate bandwidth with saturating add

By using a regular non-overflow-checking add, the MediaTek icc-emi
driver will happy wrap at U32_MAX + 1 to 0. As it's common for the
interconnect core to fill in INT_MAX values, this is not a hypothetical
situation, but something that actually happens in regular use. This
would be pretty disasterous if anything used this driver.

Replace the addition with an overflow-checked addition from overflow.h,
and saturate to U32_MAX if an overflow is detected.

Fixes: b45293799f75 ("interconnect: mediatek: Add MediaTek MT8183/8195 EMI Interconnect driver")
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Link: https://lore.kernel.org/r/20251124-mt8196-dvfsrc-v2-13-d9c1334db9f3@collabora.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>

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interconnect: mediatek: Don't hijack parent device

If the intention is that users of the interconnect declare their
relationship to the child icc_emi node of the dvfsrc controller, then
this code ne

interconnect: mediatek: Don't hijack parent device

If the intention is that users of the interconnect declare their
relationship to the child icc_emi node of the dvfsrc controller, then
this code never worked. That's because it uses the parent dvfsrc device
as the device it passes to the interconnect core framework, which means
all the OF parsing is broken.

Use the actual device instead, and pass the dvfsrc parent into the
dvfsrc calls.

Fixes: b45293799f75 ("interconnect: mediatek: Add MediaTek MT8183/8195 EMI Interconnect driver")
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Link: https://lore.kernel.org/r/20251124-mt8196-dvfsrc-v2-12-d9c1334db9f3@collabora.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>

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interconnect: mediatek: Add support for MediaTek MT8196 EMI ICC

Add a new driver with data to register the External Memory
Interface (EMI) Interconnect on the MediaTek MT8196 Chromebook
SoC.

Signed

interconnect: mediatek: Add support for MediaTek MT8196 EMI ICC

Add a new driver with data to register the External Memory
Interface (EMI) Interconnect on the MediaTek MT8196 Chromebook
SoC.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Link: https://lore.kernel.org/r/20251124-mt8196-dvfsrc-v2-11-d9c1334db9f3@collabora.com
Signed-off-by: Georgi Djakov <djakov@kernel.org>

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