[RFC PATCH 10/12] arm/tegra: Add device tree support to pinmux driver
Jamie Iles
jamie at jamieiles.com
Mon Aug 15 16:36:17 EDT 2011
On Mon, Aug 15, 2011 at 09:07:16PM +0100, Jamie Iles wrote:
> Hi Stephen,
>
> On Fri, Aug 12, 2011 at 04:54:55PM -0600, Stephen Warren wrote:
> > Signed-off-by: Stephen Warren <swarren at nvidia.com>
> > ---
> > arch/arm/mach-tegra/pinmux.c | 115 ++++++++++++++++++++++++++++++++++++++++++
> > 1 files changed, 115 insertions(+), 0 deletions(-)
> >
> > diff --git a/arch/arm/mach-tegra/pinmux.c b/arch/arm/mach-tegra/pinmux.c
> > index 05fa1a3..33246c2 100644
> > --- a/arch/arm/mach-tegra/pinmux.c
> > +++ b/arch/arm/mach-tegra/pinmux.c
> > @@ -20,6 +20,7 @@
> > #include <linux/errno.h>
> > #include <linux/spinlock.h>
> > #include <linux/io.h>
> > +#include <linux/of.h>
> > #include <linux/platform_device.h>
> >
> > #include <mach/iomap.h>
> > @@ -147,6 +148,41 @@ static const char *func_name(enum tegra_mux_func func)
> > return tegra_mux_names[func];
> > }
> >
> [...]
> >
> > static const char *tri_name(unsigned long val)
> > {
> > @@ -666,15 +702,94 @@ void tegra_pinmux_config_pullupdown_table(const struct tegra_pingroup_config *co
> > }
> > }
> >
> > +#ifdef CONFIG_OF
> > +static void __init tegra_pinmux_probe_dt(struct platform_device *pdev)
> > +{
> > + int pg;
> > +
> > + for (pg = 0; pg < TEGRA_MAX_PINGROUP; pg++) {
> > + const char *pg_name = pingroup_name(pg);
> > + struct tegra_pingroup_config config;
> > + struct device_node *pg_node;
> > + int ret;
> > + const char *s;
> > +
> > + pg_node = of_find_child_node_by_name(pdev->dev.of_node,
> > + pg_name);
> > + if (pg_node == NULL)
> > + continue;
> > +
> > + config.pingroup = pg;
> > +
> > + ret = of_property_read_string(pg_node, "nvidia,function", &s);
> > + if (ret < 0) {
> > + dev_err(&pdev->dev,
> > + "%s: Missing property nvidia,function\n",
> > + pg_name);
> > + continue;
> > + }
> > + ret = func_enum(s, &config.func);
> > + if (ret < 0) {
> > + dev_err(&pdev->dev,
> > + "%s: Invalid nvidia,function value %s\n",
> > + pg_name, s);
> > + continue;
> > + }
> > +
> > + ret = of_property_read_string(pg_node, "nvidia,pull", &s);
> > + if (ret >= 0) {
> > + if (!strcmp(s, "up"))
> > + config.pupd = TEGRA_PUPD_PULL_UP;
> > + else if (!strcmp(s, "down"))
> > + config.pupd = TEGRA_PUPD_PULL_DOWN;
> > + else if (!strcmp(s, "normal"))
> > + config.pupd = TEGRA_PUPD_NORMAL;
> > + else {
> > + dev_err(&pdev->dev,
> > + "%s: Invalid nvidia,pull value %s\n",
> > + pg_name, s);
> > + continue;
> > + }
> > + } else
> > + config.pupd = TEGRA_PUPD_NORMAL;
> > +
> > + if (of_find_property(pg_node, "nvidia,tristate", NULL))
> > + config.tristate = TEGRA_TRI_TRISTATE;
> > + else
> > + config.tristate = TEGRA_TRI_NORMAL;
> > +
> > + dev_err(&pdev->dev, "%s: func %d (%s) pull %d tri %d\n",
> > + pg_name, config.func, func_name(config.func),
> > + config.pupd, config.tristate);
> > +
> > + tegra_pinmux_config_pingroup(&config);
> > +
> > + of_node_put(pg_node);
> > + }
> > +}
>
> I need to implement DT muxing configuration for my platform, and I believe
> that what you have here would work fine for me too, and to avoid duplicating
> the same thing, I wonder if this could be a little more generic.
>
> So if the platform specific pinmux driver called the pinmux parser with a
> callback for a pingroup configuration function then this wouldn't need the
> nvidia specific properties. I'd envisage the setup callback to be something
> like:
>
> int pingroup_configure(const char *name, unsigned long flags);
and it if this took the device_node too then the platform specific bits could
handle more esoteric properties if required. I'll have a go at prototyping
this tomorrow unless there are any obvious reasons that this is a stupid idea!
Jamie
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