Subject: [PATCH v2 1/7] pinctrl: berlin: add the core pinctrl driver for Marvell Berlin SoCs

From: [email-masked] (Sebastian Hesselbarth)
Date: Sat, 26 Apr 2014 11:17:58 +0200

On 04/23/2014 05:51 PM, Antoine T?nart wrote:
> The Marvell Berlin boards have a group based pinmuxing mechanism. This
> adds the core driver support. We actually do not need any information
> about the pins here and only have the definition of the groups.
> 
> Let's take the example of the uart0 pinmuxing on the BG2Q. Balls BK4 and
> BH6 are muxed to respectively UART0 RX and TX if the group GSM12 is set
> to mode 0:
> 
> Group	Modes	Offset Base	Offset	LSB	Bit Width
> GSM12	3	sm_base		0x40	0x10	0x2
> 
> Ball	Group	Mode 0		Mode 1		Mode 2
> BK4	GSM12	UART0_RX	IrDA0_RX	GPIO9
> BH6	GSM12	UART0_TX	IrDA0_TX	GPIO10
> 
> So in order to configure BK4 -> UART0_TX and BH6 -> UART0_RX, we need
> to set (sm_base + 0x40 + 0x10) &= ff3fffff.
> 
> Signed-off-by: Antoine T?nart <[email-masked]>

Antoine,

I only have some cosmetic nits on the pinctrl driver and one fixup for
the dts.

If you resend, feel free to add my

Acked-by: Sebastian Hesselbarth <[email-masked]>

> ---
[...]
> diff --git a/drivers/pinctrl/berlin/berlin.c b/drivers/pinctrl/berlin/berlin.c
> new file mode 100644
> index 000000000000..2f89585cde20
> --- /dev/null
> +++ b/drivers/pinctrl/berlin/berlin.c
> @@ -0,0 +1,347 @@
> +/*
> + * Marvell Berlin SoC pinctrl core driver
> + *
> + * Copyright (C) 2014 Marvell Technology Group Ltd.
> + *
> + * Antoine T?nart <[email-masked]>
> + *
> + * This file is licensed under the terms of the GNU General Public
> + * License version 2. This program is licensed "as is" without any
> + * warranty of any kind, whether express or implied.
> + */
> +
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/pinctrl/pinctrl.h>
> +#include <linux/pinctrl/pinmux.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +#include "../core.h"
> +#include "../pinctrl-utils.h"
> +#include "berlin.h"
> +
> +static int berlin_pinctrl_get_group_count(struct pinctrl_dev *pctrl_dev)
> +{
> +	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> +
> +	return pctrl->desc->ngroups;
> +}
> +
> +static const char *berlin_pinctrl_get_group_name(struct pinctrl_dev *pctrl_dev,
> +						 unsigned group)
> +{
> +	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> +
> +	return pctrl->desc->groups[group].name;
> +}
> +
> +static int berlin_pinctrl_dt_node_to_map(struct pinctrl_dev *pctrl_dev,
> +					 struct device_node *node,
> +					 struct pinctrl_map **map,
> +					 unsigned *num_maps)
> +{
> +	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> +	struct property *prop;
> +	const char *function_name, *group_name;
> +	unsigned reserved_maps = 0;
> +	int ret, ngroups;
> +
> +	*map = NULL;
> +	*num_maps = 0;
> +
> +	ret = of_property_read_string(node, "marvell,function", &function_name);
> +	if (ret) {
> +		dev_err(pctrl->dev,
> +			"missing 'marvell,function' property in node %s\n",
> +			node->name);
> +		return -EINVAL;
> +	}
> +
> +	ngroups = of_property_count_strings(node, "marvell,groups");
> +	if (ngroups < 0) {
> +		dev_err(pctrl->dev,
> +			"missing 'marvell,groups' property in node %s\n",
> +			node->name);
> +		return -EINVAL;
> +	}
> +
> +	ret = pinctrl_utils_reserve_map(pctrl_dev, map, &reserved_maps,
> +					num_maps, ngroups);
> +	if (ret) {
> +		dev_err(pctrl->dev, "can't reserve map: %d\n", ret);
> +		return ret;
> +	}
> +
> +	of_property_for_each_string(node, "marvell,groups", prop, group_name) {
> +		ret = pinctrl_utils_add_map_mux(pctrl_dev, map, &reserved_maps,
> +						num_maps, group_name,
> +						function_name);
> +		if (ret) {
> +			dev_err(pctrl->dev, "can't add map: %d\n", ret);
> +			return ret;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static void berlin_pinctrl_dt_free_map(struct pinctrl_dev *pctrl_dev,
> +				       struct pinctrl_map *map,
> +				       unsigned nmaps)
> +{
> +	int i;
> +
> +	for (i = 0; i < nmaps; i++) {
> +		if (map[i].type == PIN_MAP_TYPE_MUX_GROUP) {
> +			kfree(map[i].data.mux.group);
> +
> +			/* a function can be applied to multiple groups */
> +			if (i == 0)
> +				kfree(map[i].data.mux.function);
> +		}
> +	}
> +
> +	kfree(map);
> +}
> +
> +static const struct pinctrl_ops berlin_pinctrl_ops = {
> +	.get_groups_count	= &berlin_pinctrl_get_group_count,
> +	.get_group_name		= &berlin_pinctrl_get_group_name,
> +	.dt_node_to_map		= &berlin_pinctrl_dt_node_to_map,
> +	.dt_free_map		= &berlin_pinctrl_dt_free_map,
> +};
> +
> +static int berlin_pinmux_get_functions_count(struct pinctrl_dev *pctrl_dev)
> +{
> +	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> +
> +	return pctrl->nfunctions;
> +}
> +
> +static const char *berlin_pinmux_get_function_name(struct pinctrl_dev *pctrl_dev,
> +						   unsigned function)
> +{
> +	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> +
> +	return pctrl->functions[function].name;
> +}
> +
> +static int berlin_pinmux_get_function_groups(struct pinctrl_dev *pctrl_dev,
> +					     unsigned function,
> +					     const char * const **groups,
> +					     unsigned * const num_groups)
> +{
> +	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> +
> +	*groups = pctrl->functions[function].groups;
> +	*num_groups = pctrl->functions[function].ngroups;
> +
> +	return 0;
> +}
> +
> +static struct berlin_desc_function *
> +berlin_pinctrl_find_function_by_name(struct berlin_pinctrl *pctrl,
> +				     const struct berlin_desc_group *group,
> +				     const char *fname)
> +{
> +	struct berlin_desc_function *function = group->functions;
> +
> +	while (function->name) {
> +		if (!strcmp(function->name, fname))
> +			return function;
> +
> +		function++;
> +	}
> +
> +	return NULL;
> +}
> +
> +static int berlin_pinmux_enable(struct pinctrl_dev *pctrl_dev,
> +				unsigned function,
> +				unsigned group)
> +{
> +	struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> +	const struct berlin_desc_group *group_desc = pctrl->desc->groups + group;
> +	struct berlin_pinctrl_function *func = pctrl->functions + function;
> +	struct berlin_desc_function *function_desc =
> +		berlin_pinctrl_find_function_by_name(pctrl, group_desc,
> +						     func->name);
> +	unsigned long flags;
> +	u32 regval;
> +
> +	if (!function_desc)
> +		return -EINVAL;
> +
> +	spin_lock_irqsave(&pctrl->lock, flags);
> +
> +	regval = readl(pctrl->base + group_desc->offset);
> +	regval &= GENMASK(group_desc->lsb + group_desc->bit_width - 1,
> +			  group_desc->lsb);
> +	regval |= function_desc->muxval << group_desc->lsb;
> +	writel_relaxed(regval, pctrl->base + group_desc->offset);
> +
> +	spin_unlock_irqrestore(&pctrl->lock, flags);
> +
> +	return 0;
> +}
> +
> +static const struct pinmux_ops berlin_pinmux_ops = {
> +	.get_functions_count	= &berlin_pinmux_get_functions_count,
> +	.get_function_name	= &berlin_pinmux_get_function_name,
> +	.get_function_groups	= &berlin_pinmux_get_function_groups,
> +	.enable			= &berlin_pinmux_enable,
> +};
> +
> +static int berlin_pinctrl_add_function(struct berlin_pinctrl *pctrl,
> +				       const char *name)
> +{
> +	struct berlin_pinctrl_function *function = pctrl->functions;
> +
> +	while (function->name) {
> +		if (!strcmp(function->name, name)) {
> +			function->ngroups++;
> +			return -EEXIST;
> +		}
> +		function++;
> +	}
> +
> +	function->name = name;
> +	function->ngroups = 1;
> +
> +	pctrl->nfunctions++;
> +
> +	return 0;
> +}
> +
> +static int berlin_pinctrl_build_state(struct platform_device *pdev)
> +{
> +	struct berlin_pinctrl *pctrl = platform_get_drvdata(pdev);
> +	struct berlin_desc_group const *desc_group;
> +	struct berlin_desc_function const *desc_function;
> +	int i, max_functions = 0;
> +
> +	pctrl->nfunctions = 0;
> +
> +	for (i = 0; i < pctrl->desc->ngroups; i++) {
> +		desc_group = pctrl->desc->groups + i;
> +		/* compute the maxiumum number of functions a group can have */
> +		max_functions += (1 << ((desc_group->bit_width) + 1));

nit: get rid of the outer (), they are not required.

> +	}
> +
> +	/* we will reallocate later */
> +	pctrl->functions = devm_kzalloc(&pdev->dev,
> +					max_functions * sizeof(struct berlin_pinctrl_function *),

sizeof(*pctrl->functions)?

> +					GFP_KERNEL);
> +	if (!pctrl->functions)
> +		return -ENOMEM;
> +
> +	/* register all functions */
> +	for (i = 0; i < pctrl->desc->ngroups; i++) {
> +		desc_group = pctrl->desc->groups + i;
> +		desc_function = desc_group->functions;
> +
> +		while (desc_function->name) {
> +			berlin_pinctrl_add_function(pctrl, desc_function->name);
> +			desc_function++;
> +		}
> +	}
> +
> +	pctrl->functions = krealloc(pctrl->functions,
> +				    pctrl->nfunctions * sizeof(struct berlin_pinctrl_function *),

ditto.

> +				    GFP_KERNEL);
> +
> +	/* map functions to theirs groups */
> +	for (i = 0; i < pctrl->desc->ngroups; i++) {
> +		desc_group = pctrl->desc->groups + i;
> +		desc_function = desc_group->functions;
> +
> +		while (desc_function->name) {
> +			struct berlin_pinctrl_function
> +				*function = pctrl->functions;
> +			const char **groups;
> +			bool found = false;
> +
> +			while (function->name) {
> +				if (!strcmp(desc_function->name, function->name)) {
> +					found = true;
> +					break;
> +				}
> +				function++;
> +			}
> +
> +			if (!found)
> +				return -EINVAL;
> +
> +			if (!function->groups) {
> +				function->groups =
> +					devm_kzalloc(&pdev->dev,
> +						     function->ngroups * sizeof(char *),
> +						     GFP_KERNEL);
> +
> +				if (!function->groups)
> +					return -ENOMEM;
> +			}
> +
> +			groups = function->groups;
> +			while (*groups)
> +				groups++;
> +
> +			*groups = desc_group->name;
> +
> +			desc_function++;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static struct pinctrl_desc berlin_pctrl_desc = {
> +	.name		= "berlin-pinctrl",
> +	.pctlops	= &berlin_pinctrl_ops,
> +	.pmxops		= &berlin_pinmux_ops,
> +	.owner		= THIS_MODULE,
> +};
> +
> +int berlin_pinctrl_probe(struct platform_device *pdev,
> +			 const struct berlin_pinctrl_desc *desc)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct berlin_pinctrl *pctrl;
> +	struct resource *r;
> +	int ret;
> +
> +	pctrl = devm_kzalloc(dev, sizeof(struct berlin_pinctrl), GFP_KERNEL);

sizeof(*pctrl)

> +	if (!pctrl)
> +		return -ENOMEM;
> +
> +	platform_set_drvdata(pdev, pctrl);
> +
> +	spin_lock_init(&pctrl->lock);
> +
> +	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +

Get rid of the empty line above.

> +	pctrl->base = devm_ioremap_resource(dev, r);
> +	if (IS_ERR(pctrl->base))
> +		return PTR_ERR(pctrl->base);
> +
> +	pctrl->dev = &pdev->dev;
> +	pctrl->desc = desc;
> +
> +	ret = berlin_pinctrl_build_state(pdev);
> +	if (ret) {
> +		dev_err(dev, "cannot build driver state: %d\n", ret);
> +		return ret;
> +	}
> +
> +	pctrl->pctrl_dev = pinctrl_register(&berlin_pctrl_desc, dev, pctrl);
> +	if (!pctrl->pctrl_dev) {
> +		dev_err(dev, "failed to register pinctrl driver\n");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> diff --git a/drivers/pinctrl/berlin/berlin.h b/drivers/pinctrl/berlin/berlin.h
> new file mode 100644
> index 000000000000..4118f5532038
> --- /dev/null
> +++ b/drivers/pinctrl/berlin/berlin.h
> @@ -0,0 +1,71 @@
> +/*
> + * Marvell Berlin SoC pinctrl driver.
> + *
> + * Copyright (C) 2014 Marvell Technology Group Ltd.
> + *
> + * Antoine T?nart <[email-masked]>
> + *
> + * This file is licensed under the terms of the GNU General Public
> + * License version 2. This program is licensed "as is" without any
> + * warranty of any kind, whether express or implied.
> + */
> +
> +#ifndef __PINCTRL_BERLIN_H
> +#define __PINCTRL_BERLIN_H
> +
> +struct berlin_desc_function {
> +	const char	*name;
> +	u8		muxval;
> +};
> +
> +struct berlin_desc_group {
> +	const char			*name;
> +	u8				offset;
> +	u8				bit_width;
> +	u8				lsb;
> +	struct berlin_desc_function	*functions;
> +};
> +
> +struct berlin_pinctrl_desc {
> +	const struct berlin_desc_group	*groups;
> +	unsigned			ngroups;
> +};
> +
> +struct berlin_pinctrl_function {
> +	const char	*name;
> +	const char	**groups;
> +	unsigned	ngroups;
> +};
> +
> +struct berlin_pinctrl {
> +	spinlock_t				lock;
> +	void __iomem				*base;
> +	struct device				*dev;
> +	const struct berlin_pinctrl_desc	*desc;
> +	struct berlin_pinctrl_function		*functions;
> +	unsigned				nfunctions;
> +	struct pinctrl_dev			*pctrl_dev;
> +};
> +
> +#define BERLIN_PINCTRL_GROUP(_name, _offset, _width, _lsb, ...)		\
> +	{								\
> +		.name = _name,						\
> +		.offset = _offset,					\
> +		.bit_width = _width,					\
> +		.lsb = _lsb,						\
> +		.functions = (struct berlin_desc_function[]){		\
> +			__VA_ARGS__, { } },				\
> +	}
> +
> +#define BERLIN_PINCTRL_FUNCTION(_muxval, _name)		\
> +	{						\
> +		.name = _name,				\
> +		.muxval = _muxval,			\
> +	}
> +
> +#define BERLIN_PINCTRL_FUNCTION_UNKNOW	{}

s/UNKNOW/UNKNOWN/ and in the following 3 patches, too.

Sebastian

> +
> +int berlin_pinctrl_probe(struct platform_device *pdev,
> +			 const struct berlin_pinctrl_desc *desc);
> +
> +#endif /* __PINCTRL_BERLIN_H */
>