Messages in this thread | | | Date | Mon, 27 Oct 2014 17:20:51 +0100 | Subject | Re: [PATCH 2/4] pinctrl: ralink: add a pinctrl driver for the rt2880 family of SoCs | From | Linus Walleij <> |
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On Thu, Oct 9, 2014 at 4:55 AM, John Crispin <blogic@openwrt.org> wrote:
> These Socs have 1-3 banks of 8-32 gpios. Rather then setting the muxing of each > pin individually, these socs have mux groups that when set will effect 1-N pins. > Pin groups have a 2, 4 or 8 different muxes. > > Signed-off-by: John Crispin <blogic@openwrt.org>
Overall this looks nice, some minor things....
> +struct rt2880_priv { > + struct device *dev; > + > + struct pinctrl_pin_desc *pads; > + struct pinctrl_desc *desc; > + > + struct rt2880_pmx_func **func; > + int func_count; > + > + struct rt2880_pmx_group *groups; > + const char **group_names; > + int group_count; > + > + uint8_t *gpio;
Just use u8
> + int max_pins; > +};
Some of this would need some kerneldoc, don't you think?
> +static void rt2880_pinctrl_dt_free_map(struct pinctrl_dev *pctrldev, > + struct pinctrl_map *map, unsigned num_maps) > +{ > + int i; > + > + for (i = 0; i < num_maps; i++) > + if (map[i].type == PIN_MAP_TYPE_CONFIGS_PIN || > + map[i].type == PIN_MAP_TYPE_CONFIGS_GROUP) > + kfree(map[i].data.configs.configs); > + kfree(map); > +}
Can you use pinctrl_utils_dt_free_map() from #include "pinctrl-utils.h" for this?
> +static void rt2880_pinctrl_pin_dbg_show(struct pinctrl_dev *pctrldev, > + struct seq_file *s, > + unsigned offset) > +{ > + seq_puts(s, "ralink pio"); > +}
Hmmm rather terse debug info don't you think... ;)
> +static void rt2880_pinctrl_dt_subnode_to_map(struct pinctrl_dev *pctrldev, > + struct device_node *np, > + struct pinctrl_map **map) > +{ > + const char *function; > + int func = of_property_read_string(np, "ralink,function", &function); > + int grps = of_property_count_strings(np, "ralink,group");
There are now standard bindings for "function" and "group" so please if you can, just use "function" and "group".
See: Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt "Generic pin multiplexing node content"
I also wanted to provide a generic parsing function for it actually, since so many drivers look alike.
> +static int rt2880_pinctrl_dt_node_to_map(struct pinctrl_dev *pctrldev, > + struct device_node *np_config, > + struct pinctrl_map **map, > + unsigned *num_maps) > +{ > + int max_maps = 0; > + struct pinctrl_map *tmp; > + struct device_node *np; > + > + for_each_child_of_node(np_config, np) { > + int ret = of_property_count_strings(np, "ralink,group"); > + > + if (ret >= 0) > + max_maps += ret; > + } > + > + if (!max_maps) > + return max_maps; > + > + *map = kzalloc(max_maps * sizeof(struct pinctrl_map), > + GFP_KERNEL);
Can you use pinctrl_utils_reserve_map() here?
> +static int rt2880_pmx_group_enable(struct pinctrl_dev *pctrldev, > + unsigned func, > + unsigned group)
We don't have an "enable" callback anymore. Rename this rt2880_pmx_set_mux().
> +static const struct pinmux_ops rt2880_pmx_group_ops = { > + .get_functions_count = rt2880_pmx_func_count, > + .get_function_name = rt2880_pmx_func_name, > + .get_function_groups = rt2880_pmx_group_get_groups, > + .enable = rt2880_pmx_group_enable,
.set_mux rather than .enable
And make sure you test this on say v3.18-rc2.
> +static struct rt2880_pmx_func gpio_func = { > + .name = "gpio", > +};
Hmmmmmm
> +static int rt2880_pinmux_index(struct rt2880_priv *p) > +{ > + struct rt2880_pmx_func **f; > + struct rt2880_pmx_group *mux = p->groups; > + int i, j, c = 0; > + > + /* count the mux functions */ > + while (mux->name) { > + p->group_count++; > + mux++; > + } > + > + /* allocate the group names array needed by the gpio function */ > + p->group_names = devm_kzalloc(p->dev, > + sizeof(char *) * p->group_count, GFP_KERNEL); > + if (!p->group_names) > + return -1; > + > + for (i = 0; i < p->group_count; i++) { > + p->group_names[i] = p->groups[i].name; > + p->func_count += p->groups[i].func_count; > + } > + > + /* we have a dummy function[0] for gpio */ > + p->func_count++; > + > + /* allocate our function and group mapping index buffers */ > + f = p->func = devm_kzalloc(p->dev, > + sizeof(struct rt2880_pmx_func) * p->func_count, GFP_KERNEL); > + gpio_func.groups = devm_kzalloc(p->dev, sizeof(int) * p->group_count, > + GFP_KERNEL); > + if (!f || !gpio_func.groups) > + return -1;
Can you explain what this code is doing a bit more.
Are you avoiding to use gpio ranges by instead providing that "gpio" function on each and every pin?
> +static int rt2880_pinmux_probe(struct platform_device *pdev) > +{ > + struct rt2880_priv *p; > + struct pinctrl_dev *dev; > + struct device_node *np; > + > + if (!rt2880_pinmux_data) > + return -ENOSYS; > + > + /* setup the private data */ > + p = devm_kzalloc(&pdev->dev, sizeof(struct rt2880_priv), GFP_KERNEL); > + if (!p) > + return -ENOMEM; > + > + p->dev = &pdev->dev; > + p->desc = &rt2880_pctrl_desc; > + p->groups = rt2880_pinmux_data; > + platform_set_drvdata(pdev, p); > + > + /* init the device */ > + if (rt2880_pinmux_index(p)) { > + dev_err(&pdev->dev, "failed to load index\n"); > + return -EINVAL; > + } > + if (rt2880_pinmux_pins(p)) { > + dev_err(&pdev->dev, "failed to load pins\n"); > + return -EINVAL; > + }
What is this "loading" that is happening here?
> + dev = pinctrl_register(p->desc, &pdev->dev, p); > + if (IS_ERR(dev)) > + return PTR_ERR(dev); > + > + /* finalize by adding gpio ranges for enables gpio controllers */ > + for_each_compatible_node(np, NULL, "ralink,rt2880-gpio") { > + const __be32 *ngpio, *gpiobase; > + struct pinctrl_gpio_range *range; > + char *name; > + > + if (!of_device_is_available(np)) > + continue; > + > + ngpio = of_get_property(np, "ralink,num-gpios", NULL); > + gpiobase = of_get_property(np, "ralink,gpio-base", NULL);
NO GPIO BASE in the device tree.
We have NACKed this so many times that I don't know it anymore.
The gpiobase is a linux-internal thing and not OS neutral at all.
So it has nothing to do in the device tree.
(If it was allowed it would atleast be linux,gpio-base)
Several other ways to handle this is available, the best being... (see below)
> + if (!ngpio || !gpiobase) { > + dev_err(&pdev->dev, "failed to load chip info\n"); > + return -EINVAL; > + } > + > + range = devm_kzalloc(p->dev, > + sizeof(struct pinctrl_gpio_range) + 4, GFP_KERNEL); > + range->name = name = (char *) &range[1]; > + sprintf(name, "pio"); > + range->npins = __be32_to_cpu(*ngpio); > + range->base = __be32_to_cpu(*gpiobase); > + range->pin_base = range->base; > + pinctrl_add_gpio_range(dev, range);
...to NOT do this but instead use gpiochip_add_pin_range() or gpiochip_add_pingroup_range() from the gpiochip side.
The gpiochip has the ability to add ranges completely dynamically as it can get a relative offset from the pin control subsystem. It doesn't work the other way around unfortunately.
So I'd suggest you look at ways to modify your GPIO driver to do this.
> +core_initcall_sync(rt2880_pinmux_init);
Do you really need it this early?
Yours, Linus Walleij
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