Messages in this thread | | | Date | Thu, 23 Feb 2012 07:08:35 +0100 | Subject | Re: [PATCH 20/20] pinctrl: Enhance mapping table to support pin config operations | From | Linus Walleij <> |
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On Mon, Feb 20, 2012 at 7:46 AM, Stephen Warren <swarren@nvidia.com> wrote:
> The pinctrl mapping table can now contain entries to: > * Set the mux function of a pin group > * Apply a set of pin config options to a pin or a group > > This allows pinctrl_select_state() to apply pin configs settings as well > as mux settings. > > Signed-off-by: Stephen Warren <swarren@nvidia.com>
Overall excellent, just smaller things below:
> @@ -817,7 +827,40 @@ it even more compact which assumes you want to use pinctrl-foo and position > 0 for mapping, for example: > > static struct pinctrl_map __initdata mapping[] = { > - PIN_MAP("default", "pinctrl-foo", "i2c0", "foo-i2c.0"), > + PIN_MAP_MUX_GROUP("foo-i2c.o", "default", "pinctrl-foo", NULL, "i2c0"), > +};
OK looks good!
> +The mapping table may also contain pin configuration entries. It's common for > +each pin/group to have a number of configuration entries that affect it, so > +the table entries for configuration reference an array of config parameters > +and values. An example using the convenience macros is shown below: > + > +static unsigned long i2c_grp_configs[] = { > + FOO_PIN_DRIVEN, > + FOO_PIN_PULLUP, > +}; > + > +static unsigned long i2c_pin_configs[] = { > + FOO_OPEN_COLLECTOR, > + FOO_SLEW_RATE_SLOW, > +}; > + > +static struct pinctrl_map __initdata mapping[] = { > + PIN_MAP_MUX_GROUP("foo-i2c.0", "default", "pinctrl-foo", "i2c0", "i2c0"), > + PIN_MAP_MUX_CONFIGS_GROUP("foo-i2c.0", "default", "pinctrl-foo", "i2c0", i2c_grp_configs), > + PIN_MAP_MUX_CONFIGS_PIN("foo-i2c.0", "default", "pinctrl-foo", "i2c0scl", i2c_pin_configs), > + PIN_MAP_MUX_CONFIGS_PIN("foo-i2c.0", "default", "pinctrl-foo", "i2c0sda", i2c_pin_configs), > +};
I buy this too...
> +Finally, some devices expect the mapping table to contain certain specific > +named states. When running on hardware that doesn't need any pin controller > +configuration, the mapping table must still contain those named states, in > +order to explicitly indicate that the states were provided and intended to > +be empty. Table entry macro PIN_MAP_DUMMY_STATE serves the purpose of defining > +a named state without causing any pin controller to be programmed: > + > +static struct pinctrl_map __initdata mapping[] = { > + PIN_MAP_DUMMY_STATE("foo-i2c.0", "default"), > };
Looks useful so why not.
> @@ -1022,7 +1074,7 @@ Since it may be common to request the core to hog a few always-applicable > mux settings on the primary pin controller, there is a convenience macro for > this: > > -PIN_MAP_SYS_HOG("active", "pinctrl-foo", "power_func") > +PIN_MAP_MUX_GROUP("pinctrl-foo", "active", "pinctrl-foo", NULL, "power_func")
Please keep the explicit _HOG macros for readability. Relying on the implicit relation between dev and pctldev being the same and to be parsed by humans is vulnerable.
PIN_MAP_MUX_GROUP_HOG()
in this case, with the same arguments (though with PINCTRL_STATE_DEFAULT in place for "active") is better IMO.
> /* Pinmux settings */ > static struct pinctrl_map __initdata u300_pinmux_map[] = { > /* anonymous maps for chip power and EMIFs */ > - PIN_MAP_SYS_HOG("default", "pinmux-u300", "power"), > - PIN_MAP_SYS_HOG("default", "pinmux-u300", "emif0"), > - PIN_MAP_SYS_HOG("default", "pinmux-u300", "emif1"), > + PIN_MAP_MUX_GROUP("pinmux-u300", "default", "pinmux-u300", NULL, "power"), > + PIN_MAP_MUX_GROUP("pinmux-u300", "default", "pinmux-u300", NULL, "emif0"), > + PIN_MAP_MUX_GROUP("pinmux-u300", "default", "pinmux-u300", NULL, "emif1"), > /* per-device maps for MMC/SD, SPI and UART */ > - PIN_MAP("default", "pinmux-u300", "mmc0", "mmci"), > - PIN_MAP("default", "pinmux-u300", "spi0", "pl022"), > - PIN_MAP("default", "pinmux-u300", "uart0", "uart0"), > + PIN_MAP_MUX_GROUP("mmci", "default", "pinmux-u300", NULL, "mmc0"), > + PIN_MAP_MUX_GROUP("pl022", "default", "pinmux-u300", NULL, "spi0"), > + PIN_MAP_MUX_GROUP("uart0", "default", "pinmux-u300", NULL, "uart0"), > };
PIN_MAP_MUX_GROUP_HOG() please. PINCTRL_STATE_DEFAULT instead of "default".
Or maybe we should imply that PIN_MAP_MUX_GROUP_HOG() hogs the default state, or have PIN_MAP_MUX_GROUP_HOG_DEFAULT() even?
> --- a/drivers/pinctrl/core.c > +++ b/drivers/pinctrl/core.c > @@ -341,6 +341,31 @@ int pinctrl_get_group_selector(struct pinctrl_dev *pctldev, > } > > /** > + * pinctrl_get_pin_id() - returns the group selector for a group > + * @pctldev: the pin controller handling the group > + * @pin_group: the pin group to look up
This kerneldoc is wrong... pin, not group.
> + */ > +int pinctrl_get_pin_id(struct pinctrl_dev *pctldev, > + const char *pin) > +{ > + unsigned int i; > + > + for (i = 0; i < pctldev->desc->npins; i++) { > + if (pctldev->desc->pins[i].name == NULL) > + continue; > + if (!strcmp(pin, pctldev->desc->pins[i].name)) { > + dev_dbg(pctldev->dev, "found pin id %u for %s\n", > + i, pin); > + return i; > + } > + }
(...)
> /* First sanity check the new mapping */ > for (i = 0; i < num_maps; i++) { > + if (!maps[i].dev_name) { > + pr_err("failed to register map %s (%d): no device given\n", > + maps[i].name, i); > + return -EINVAL; > + } > +
Hm should this not be done earlier in the patch series?
> + /* > + * FIXME: We should really get the pin controler to dump the config > + * values, so they can be decoded to something meaningful. > + */ > + for (i = 0; i < setting->data.configs.num_configs; i++) > + seq_printf(s, " %08lx", setting->data.configs.configs[i]); > + > + seq_printf(s, "\n"); > +}
Per-device config print function? But no need to rush that.
Apart from this I mostly just trust this patch, like the previous one.
Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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