path: root/drivers/pinctrl/pxa/pinctrl-pxa2xx.c

/*
 * Marvell PXA2xx family pin control
 *
 * Copyright (C) 2015 Robert Jarzmik
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 */

#include <linux/bitops.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/module.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#include "../pinctrl-utils.h"
#include "pinctrl-pxa2xx.h"

static int pxa2xx_pctrl_get_groups_count(struct pinctrl_dev *pctldev)
{
	struct pxa_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);

	return pctl->ngroups;
}

static const char *pxa2xx_pctrl_get_group_name(struct pinctrl_dev *pctldev,
					       unsigned tgroup)
{
	struct pxa_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
	struct pxa_pinctrl_group *group = pctl->groups + tgroup;

	return group->name;
}

static int pxa2xx_pctrl_get_group_pins(struct pinctrl_dev *pctldev,
				       unsigned tgroup,
				       const unsigned **pins,
				       unsigned *num_pins)
{
	struct pxa_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
	struct pxa_pinctrl_group *group = pctl->groups + tgroup;

	*pins = (unsigned *)&group->pin;
	*num_pins = 1;

	return 0;
}

static const struct pinctrl_ops pxa2xx_pctl_ops = {
#ifdef CONFIG_OF
	.dt_node_to_map		= pinconf_generic_dt_node_to_map_all,
	.dt_free_map		= pinctrl_utils_dt_free_map,
#endif
	.get_groups_count	= pxa2xx_pctrl_get_groups_count,
	.get_group_name		= pxa2xx_pctrl_get_group_name,
	.get_group_pins		= pxa2xx_pctrl_get_group_pins,
};

static struct pinctrl_desc pxa2xx_pinctrl_desc = {
	.pctlops	= &pxa2xx_pctl_ops,
};

static const struct pxa_pinctrl_function *
pxa2xx_find_function(struct pxa_pinctrl *pctl, const char *fname,
		     const struct pxa_pinctrl_function *functions)
{
	const struct pxa_pinctrl_function *func;

	for (func = functions; func->name; func++)
		if (!strcmp(fname, func->name))
			return func;

	return NULL;
}

static int pxa2xx_build_functions(struct pxa_pinctrl *pctl)
{
	int i;
	struct pxa_pinctrl_function *functions;
	struct pxa_desc_function *df;

	/*
	 * Each pin can have at most 6 alternate functions, and 2 gpio functions
	 * which are common to each pin. As there are more than 2 pins without
	 * alternate function, 6 * npins is an absolute high limit of the number
	 * of functions.
	 */
	functions = devm_kcalloc(pctl->dev, pctl->npins * 6,
				 sizeof(*functions), GFP_KERNEL);
	if (!functions)
		return -ENOMEM;

	for (i = 0; i < pctl->npins; i++)
		for (df = pctl->ppins[i].functions; df->name; df++)
			if (!pxa2xx_find_function(pctl, df->name, functions))
				(functions + pctl->nfuncs++)->name = df->name;
	pctl->functions = devm_kmemdup(pctl->dev, functions,
				       pctl->nfuncs * sizeof(*functions),
				       GFP_KERNEL);
	if (!pctl->functions)
		return -ENOMEM;

	kfree(functions);
	return 0;
}

static int pxa2xx_build_groups(struct pxa_pinctrl *pctl)
{
	int i, j, ngroups;
	struct pxa_pinctrl_function *func;
	struct pxa_desc_function *df;
	char **gtmp;

	gtmp = devm_kmalloc_array(pctl->dev, pctl->npins, sizeof(*gtmp),
				  GFP_KERNEL);
	if (!gtmp)
		return -ENOMEM;

	for (i = 0; i < pctl->nfuncs; i++) {
		ngroups = 0;
		for (j = 0; j < pctl->npins; j++)
			for (df = pctl->ppins[j].functions; df->name;
			     df++)
				if (!strcmp(pctl->functions[i].name,
					    df->name))
					gtmp[ngroups++] = (char *)
						pctl->ppins[j].pin.name;
		func = pctl->functions + i;
		func->ngroups = ngroups;
		func->groups =
			devm_kmalloc_array(pctl->dev, ngroups,
					   sizeof(char *), GFP_KERNEL);
		if (!func->groups)
			return -ENOMEM;

		memcpy(func->groups, gtmp, ngroups * sizeof(*gtmp));
	}

	kfree(gtmp);
	return 0;
}

static int pxa2xx_build_state(struct pxa_pinctrl *pctl,
			      const struct pxa_desc_pin *ppins, int npins)
{
	struct pxa_pinctrl_group *group;
	struct pinctrl_pin_desc *pins;
	int ret, i;

	pctl->npins = npins;
	pctl->ppins = ppins;
	pctl->ngroups = npins;

	pctl->desc.npins = npins;
	pins = devm_kcalloc(pctl->dev, npins, sizeof(*pins), GFP_KERNEL);
	if (!pins)
		return -ENOMEM;

	pctl->desc.pins = pins;
	for (i = 0; i < npins; i++)
		pins[i] = ppins[i].pin;

	pctl->groups = devm_kmalloc_array(pctl->dev, pctl->ngroups,
					  sizeof(*pctl->groups), GFP_KERNEL);
	if (!pctl->groups)
		return -ENOMEM;

	for (i = 0; i < npins; i++) {
		group = pctl->groups + i;
		group->name = ppins[i].pin.name;
		group->pin = ppins[i].pin.number;
	}

	ret = pxa2xx_build_functions(pctl);
	if (ret)
		return ret;

	ret = pxa2xx_build_groups(pctl);
	if (ret)
		return ret;

	return 0;
}

int pxa2xx_pinctrl_init(struct platform_device *pdev,
			const struct pxa_desc_pin *ppins, int npins,
			void __iomem *base_gafr[], void __iomem *base_gpdr[],
			void __iomem *base_pgsr[])
{
	struct pxa_pinctrl *pctl;
	int ret, i, maxpin = 0;

	for (i = 0; i < npins; i++)
		maxpin = max_t(int, ppins[i].pin.number, maxpin);

	pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
	if (!pctl)
		return -ENOMEM;
	pctl->base_gafr = devm_kcalloc(&pdev->dev, roundup(maxpin, 16),
				       sizeof(*pctl->base_gafr), GFP_KERNEL);
	pctl->base_gpdr = devm_kcalloc(&pdev->dev, roundup(maxpin, 32),
				       sizeof(*pctl->base_gpdr), GFP_KERNEL);
	pctl->base_pgsr = devm_kcalloc(&pdev->dev, roundup(maxpin, 32),
				       sizeof(*pctl->base_pgsr), GFP_KERNEL);
	if (!pctl->base_gafr || !pctl->base_gpdr || !pctl->base_pgsr)
		return -ENOMEM;

	platform_set_drvdata(pdev, pctl);
	spin_lock_init(&pctl->lock);

	pctl->dev = &pdev->dev;
	pctl->desc = pxa2xx_pinctrl_desc;
	pctl->desc.name = dev_name(&pdev->dev);
	pctl->desc.owner = THIS_MODULE;

	for (i = 0; i < roundup(maxpin, 16); i += 16)
		pctl->base_gafr[i / 16] = base_gafr[i / 16];
	for (i = 0; i < roundup(maxpin, 32); i += 32) {
		pctl->base_gpdr[i / 32] = base_gpdr[i / 32];
		pctl->base_pgsr[i / 32] = base_pgsr[i / 32];
	}

	ret = pxa2xx_build_state(pctl, ppins, npins);
	if (ret)
		return ret;

	pctl->pctl_dev = pinctrl_register(&pctl->desc, &pdev->dev, pctl);
	if (IS_ERR(pctl->pctl_dev)) {
		dev_err(&pdev->dev, "couldn't register pinctrl driver\n");
		return PTR_ERR(pctl->pctl_dev);
	}

	dev_info(&pdev->dev, "initialized pxa2xx pinctrl driver\n");

	return 0;
}

int pxa2xx_pinctrl_exit(struct platform_device *pdev)
{
	struct pxa_pinctrl *pctl = platform_get_drvdata(pdev);

	pinctrl_unregister(pctl->pctl_dev);
	return 0;
}