2015-05-05 17:50 GMT+02:00 Sascha Hauer [off-list ref]:

On Tue, May 05, 2015 at 05:41:16PM +0200, Matthias Brugger wrote:

quoted

2015-04-27 8:49 GMT+02:00 Sascha Hauer [off-list ref]:

quoted

The mtk 8250 needs two clocks, one for providing the baudrate and
one that needs to be enabled for register accesses. The latter has
not been supported, this patch adds support for it. It is optional
for now since not all SoCs provide a bus clock.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 .../devicetree/bindings/serial/mtk-uart.txt        | 12 ++++++++--
 drivers/tty/serial/8250/8250_mtk.c                 | 28 ++++++++++++++++++----
 2 files changed, 34 insertions(+), 6 deletions(-)

diff --git a/Documentation/devicetree/bindings/serial/mtk-uart.txt b/Documentation/devicetree/bindings/serial/mtk-uart.txt
index 4415226..8d63f1d 100644
--- a/Documentation/devicetree/bindings/serial/mtk-uart.txt
+++ b/Documentation/devicetree/bindings/serial/mtk-uart.txt

@@ -14,7 +14,14 @@ Required properties:

 - interrupts: A single interrupt specifier.

-- clocks: Clock driving the hardware.
+- clocks : Must contain an entry for each entry in clock-names.
+  See ../clocks/clock-bindings.txt for details.
+- clock-names:
+  - "baud": The clock the baudrate is derived from
+  - "bus": The bus clock for register accesses (optional)
+
+For compatibility with older device trees an unnamed clock is used for the
+baud clock if the baudclk does not exist. Do not use this for new designs.

 Example:

@@ -22,5 +29,6 @@ Example:
                compatible = "mediatek,mt6589-uart", "mediatek,mt6577-uart";
                reg = <0x11006000 0x400>;
                interrupts = <GIC_SPI 51 IRQ_TYPE_LEVEL_LOW>;
-               clocks = <&uart_clk>;
+               clocks = <&uart_clk>, <&bus_clk>;
+               clock-names = "baud", "bus";
        };

diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
index 2f28bd0..8eb3876 100644
--- a/drivers/tty/serial/8250/8250_mtk.c
+++ b/drivers/tty/serial/8250/8250_mtk.c

@@ -34,6 +34,7 @@
 struct mtk8250_data {
        int                     line;
        struct clk              *uart_clk;
+       struct clk              *bus_clk;
 };

Not sure if it would be better to rename the uart_clk to baud_clk
which reflects the new naming scheme.

Can do.

If you do so you can add:
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>

Thanks,
Matthias
-- 
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