Re: [PATCH 1/2] tty: amba-pl011: add support for clock frequency setting via dt

From: Michael Turquette
Date: Fri Jul 08 2016 - 20:23:17 EST


Quoting Jorge Ramirez (2016-07-08 14:39:50)
> On 07/08/2016 07:14 PM, Michael Turquette wrote:
> > Quoting Jorge Ramirez-Ortiz (2016-07-08 01:11:06)
> >> Allow to specify the clock frequency for any given port via the
> >> assigned-clock-rates device tree property.
> >>
> >> Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx>
> >> Tested-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx>
> >> ---
> >> drivers/tty/serial/amba-pl011.c | 5 +++++
> >> 1 file changed, 5 insertions(+)
> >>
> >> diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
> >> index 1b7331e..51867ab 100644
> >> --- a/drivers/tty/serial/amba-pl011.c
> >> +++ b/drivers/tty/serial/amba-pl011.c
> >> @@ -55,6 +55,7 @@
> >> #include <linux/types.h>
> >> #include <linux/of.h>
> >> #include <linux/of_device.h>
> >> +#include <linux/clk/clk-conf.h>
> >> #include <linux/pinctrl/consumer.h>
> >> #include <linux/sizes.h>
> >> #include <linux/io.h>
> >> @@ -2472,6 +2473,10 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
> >> if (IS_ERR(uap->clk))
> >> return PTR_ERR(uap->clk);
> >>
> >> + ret = of_clk_set_defaults(dev->dev.of_node, false);
> > Change looks good to me, but with one question: should this change be
> > put into more generic code instead of in this specific driver? For
> > instance, we call of_clk_set_defaults from the following files:
> >
> > drivers/base/platform.c
> > drivers/i2c/i2c-core.c
> > drivers/spi/spi.c
> >
> > And Stephen posted a patch to do this for devices on the AMBA bus:
> >
> > https://patchwork.kernel.org/patch/6501691/
> >
> > Does Stephen's patch mean that you do not need patch #1?
>
> I did a quick test (replaced my changes with the patch above) and the
> console broke and the BT stack couldn't communicate to the device over
> the uart...I guess something else needs doing on top of Stephen's change.
>

Let's give Stephen a chance to respond. If he doesn't soon then I'm OK
to merge your two patches.

Regards,
Mike