pinctrl: pinctrl-imx: add imx pinctrl core driver

The driver has mux and config support while the gpio is still
not supported.
For select input setting, the driver will handle it internally
and do not need user to take care of it.

The pinctrl-imx core driver will parse the dts file and dynamically
create the pinmux functions and groups.

Each IMX SoC pinctrl driver should register pins with a pin register map
including mux register and config register and select input map to core
for proper operations.

Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 627 insertions, 0 deletions

diff --git a/drivers/pinctrl/pinctrl-imx.c b/drivers/pinctrl/pinctrl-imx.c
new file mode 100644
index 000000000000..8faf613ff1b2
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-imx.c
@@ -0,0 +1,627 @@
+/*
+ * Core driver for the imx pin controller
+ *
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ * Copyright (C) 2012 Linaro Ltd.
+ *
+ * Author: Dong Aisheng <dong.aisheng@linaro.org>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/machine.h>
+#include <linux/pinctrl/pinconf.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+#include <linux/slab.h>
+
+#include "core.h"
+#include "pinctrl-imx.h"
+
+#define IMX_PMX_DUMP(info, p, m, c, n)		\
+{						\
+	int i, j;				\
+	printk("Format: Pin Mux Config\n");	\
+	for (i = 0; i < n; i++) {		\
+		j = p[i];			\
+		printk("%s %d 0x%lx\n",		\
+			info->pins[j].name,	\
+			m[i], c[i]);		\
+	}					\
+}
+
+/* The bits in CONFIG cell defined in binding doc*/
+#define IMX_NO_PAD_CTL	0x80000000	/* no pin config need */
+#define IMX_PAD_SION 0x40000000		/* set SION */
+
+/**
+ * @dev: a pointer back to containing device
+ * @base: the offset to the controller in virtual memory
+ */
+struct imx_pinctrl {
+	struct device *dev;
+	struct pinctrl_dev *pctl;
+	void __iomem *base;
+	const struct imx_pinctrl_soc_info *info;
+};
+
+static const struct imx_pin_reg *imx_find_pin_reg(
+				const struct imx_pinctrl_soc_info *info,
+				unsigned pin, bool is_mux, unsigned mux)
+{
+	const struct imx_pin_reg *pin_reg = NULL;
+	int i;
+
+	for (i = 0; i < info->npin_regs; i++) {
+		pin_reg = &info->pin_regs[i];
+		if (pin_reg->pid != pin)
+			continue;
+		if (!is_mux)
+			break;
+		else if (pin_reg->mux_mode == (mux & IMX_MUX_MASK))
+			break;
+	}
+
+	if (!pin_reg) {
+		dev_err(info->dev, "Pin(%s): unable to find pin reg map\n",
+			info->pins[pin].name);
+		return NULL;
+	}
+
+	return pin_reg;
+}
+
+static const inline struct imx_pin_group *imx_pinctrl_find_group_by_name(
+				const struct imx_pinctrl_soc_info *info,
+				const char *name)
+{
+	const struct imx_pin_group *grp = NULL;
+	int i;
+
+	for (i = 0; i < info->ngroups; i++) {
+		if (!strcmp(info->groups[i].name, name)) {
+			grp = &info->groups[i];
+			break;
+		}
+	}
+
+	return grp;
+}
+
+static int imx_get_groups_count(struct pinctrl_dev *pctldev)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+
+	return info->ngroups;
+}
+
+static const char *imx_get_group_name(struct pinctrl_dev *pctldev,
+				       unsigned selector)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+
+	return info->groups[selector].name;
+}
+
+static int imx_get_group_pins(struct pinctrl_dev *pctldev, unsigned selector,
+			       const unsigned **pins,
+			       unsigned *npins)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+
+	if (selector >= info->ngroups)
+		return -EINVAL;
+
+	*pins = info->groups[selector].pins;
+	*npins = info->groups[selector].npins;
+
+	return 0;
+}
+
+static void imx_pin_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s,
+		   unsigned offset)
+{
+	seq_printf(s, "%s", dev_name(pctldev->dev));
+}
+
+static int imx_dt_node_to_map(struct pinctrl_dev *pctldev,
+			struct device_node *np,
+			struct pinctrl_map **map, unsigned *num_maps)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+	const struct imx_pin_group *grp;
+	struct pinctrl_map *new_map;
+	struct device_node *parent;
+	int map_num = 1;
+	int i;
+
+	/*
+	 * first find the group of this node and check if we need create
+	 * config maps for pins
+	 */
+	grp = imx_pinctrl_find_group_by_name(info, np->name);
+	if (!grp) {
+		dev_err(info->dev, "unable to find group for node %s\n",
+			np->name);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < grp->npins; i++) {
+		if (!(grp->configs[i] & IMX_NO_PAD_CTL))
+			map_num++;
+	}
+
+	new_map = kmalloc(sizeof(struct pinctrl_map) * map_num, GFP_KERNEL);
+	if (!new_map)
+		return -ENOMEM;
+
+	*map = new_map;
+	*num_maps = map_num;
+
+	/* create mux map */
+	parent = of_get_parent(np);
+	if (!parent)
+		return -EINVAL;
+	new_map[0].type = PIN_MAP_TYPE_MUX_GROUP;
+	new_map[0].data.mux.function = parent->name;
+	new_map[0].data.mux.group = np->name;
+	of_node_put(parent);
+
+	/* create config map */
+	new_map++;
+	for (i = 0; i < grp->npins; i++) {
+		if (!(grp->configs[i] & IMX_NO_PAD_CTL)) {
+			new_map[i].type = PIN_MAP_TYPE_CONFIGS_PIN;
+			new_map[i].data.configs.group_or_pin =
+					pin_get_name(pctldev, grp->pins[i]);
+			new_map[i].data.configs.configs = &grp->configs[i];
+			new_map[i].data.configs.num_configs = 1;
+		}
+	}
+
+	dev_dbg(pctldev->dev, "maps: function %s group %s num %d\n",
+		new_map->data.mux.function, new_map->data.mux.group, map_num);
+
+	return 0;
+}
+
+static void imx_dt_free_map(struct pinctrl_dev *pctldev,
+				struct pinctrl_map *map, unsigned num_maps)
+{
+	int i;
+
+	for (i = 0; i < num_maps; i++)
+		kfree(map);
+}
+
+static struct pinctrl_ops imx_pctrl_ops = {
+	.get_groups_count = imx_get_groups_count,
+	.get_group_name = imx_get_group_name,
+	.get_group_pins = imx_get_group_pins,
+	.pin_dbg_show = imx_pin_dbg_show,
+	.dt_node_to_map = imx_dt_node_to_map,
+	.dt_free_map = imx_dt_free_map,
+
+};
+
+static int imx_pmx_enable(struct pinctrl_dev *pctldev, unsigned selector,
+			   unsigned group)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+	const struct imx_pin_reg *pin_reg;
+	const unsigned *pins, *mux;
+	unsigned int npins, pin_id;
+	int i;
+
+	/*
+	 * Configure the mux mode for each pin in the group for a specific
+	 * function.
+	 */
+	pins = info->groups[group].pins;
+	npins = info->groups[group].npins;
+	mux = info->groups[group].mux_mode;
+
+	WARN_ON(!pins || !npins || !mux);
+
+	dev_dbg(ipctl->dev, "enable function %s group %s\n",
+		info->functions[selector].name, info->groups[group].name);
+
+	for (i = 0; i < npins; i++) {
+		pin_id = pins[i];
+
+		pin_reg = imx_find_pin_reg(info, pin_id, 1, mux[i]);
+		if (!pin_reg)
+			return -EINVAL;
+
+		if (!pin_reg->mux_reg) {
+			dev_err(ipctl->dev, "Pin(%s) does not support mux function\n",
+				info->pins[pin_id].name);
+			return -EINVAL;
+		}
+
+		writel(mux[i], ipctl->base + pin_reg->mux_reg);
+		dev_dbg(ipctl->dev, "write: offset 0x%x val 0x%x\n",
+			pin_reg->mux_reg, mux[i]);
+
+		/* some pins also need select input setting, set it if found */
+		if (pin_reg->input_reg) {
+			writel(pin_reg->input_val, ipctl->base + pin_reg->input_reg);
+			dev_dbg(ipctl->dev,
+				"==>select_input: offset 0x%x val 0x%x\n",
+				pin_reg->input_reg, pin_reg->input_val);
+		}
+	}
+
+	return 0;
+}
+
+static void imx_pmx_disable(struct pinctrl_dev *pctldev, unsigned func_selector,
+			    unsigned group_selector)
+{
+	/* nothing to do here */
+}
+
+static int imx_pmx_get_funcs_count(struct pinctrl_dev *pctldev)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+
+	return info->nfunctions;
+}
+
+static const char *imx_pmx_get_func_name(struct pinctrl_dev *pctldev,
+					  unsigned selector)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+
+	return info->functions[selector].name;
+}
+
+static int imx_pmx_get_groups(struct pinctrl_dev *pctldev, unsigned selector,
+			       const char * const **groups,
+			       unsigned * const num_groups)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+
+	*groups = info->functions[selector].groups;
+	*num_groups = info->functions[selector].num_groups;
+
+	return 0;
+}
+
+static struct pinmux_ops imx_pmx_ops = {
+	.get_functions_count = imx_pmx_get_funcs_count,
+	.get_function_name = imx_pmx_get_func_name,
+	.get_function_groups = imx_pmx_get_groups,
+	.enable = imx_pmx_enable,
+	.disable = imx_pmx_disable,
+};
+
+static int imx_pinconf_get(struct pinctrl_dev *pctldev,
+			     unsigned pin_id, unsigned long *config)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+	const struct imx_pin_reg *pin_reg;
+
+	pin_reg = imx_find_pin_reg(info, pin_id, 0, 0);
+	if (!pin_reg)
+		return -EINVAL;
+
+	if (!pin_reg->conf_reg) {
+		dev_err(info->dev, "Pin(%s) does not support config function\n",
+			info->pins[pin_id].name);
+		return -EINVAL;
+	}
+
+	*config = readl(ipctl->base + pin_reg->conf_reg);
+
+	return 0;
+}
+
+static int imx_pinconf_set(struct pinctrl_dev *pctldev,
+			     unsigned pin_id, unsigned long config)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+	const struct imx_pin_reg *pin_reg;
+
+	pin_reg = imx_find_pin_reg(info, pin_id, 0, 0);
+	if (!pin_reg)
+		return -EINVAL;
+
+	if (!pin_reg->conf_reg) {
+		dev_err(info->dev, "Pin(%s) does not support config function\n",
+			info->pins[pin_id].name);
+		return -EINVAL;
+	}
+
+	dev_dbg(ipctl->dev, "pinconf set pin %s\n",
+		info->pins[pin_id].name);
+
+	writel(config, ipctl->base + pin_reg->conf_reg);
+	dev_dbg(ipctl->dev, "write: offset 0x%x val 0x%lx\n",
+		pin_reg->conf_reg, config);
+
+	return 0;
+}
+
+static void imx_pinconf_dbg_show(struct pinctrl_dev *pctldev,
+				   struct seq_file *s, unsigned pin_id)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+	const struct imx_pin_reg *pin_reg;
+	unsigned long config;
+
+	pin_reg = imx_find_pin_reg(info, pin_id, 0, 0);
+	if (!pin_reg || !pin_reg->conf_reg) {
+		seq_printf(s, "N/A");
+		return;
+	}
+
+	config = readl(ipctl->base + pin_reg->conf_reg);
+	seq_printf(s, "0x%lx", config);
+}
+
+static void imx_pinconf_group_dbg_show(struct pinctrl_dev *pctldev,
+					 struct seq_file *s, unsigned group)
+{
+	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
+	const struct imx_pinctrl_soc_info *info = ipctl->info;
+	struct imx_pin_group *grp;
+	unsigned long config;
+	const char *name;
+	int i, ret;
+
+	if (group > info->ngroups)
+		return;
+
+	seq_printf(s, "\n");
+	grp = &info->groups[group];
+	for (i = 0; i < grp->npins; i++) {
+		name = pin_get_name(pctldev, grp->pins[i]);
+		ret = imx_pinconf_get(pctldev, grp->pins[i], &config);
+		if (ret)
+			return;
+		seq_printf(s, "%s: 0x%lx", name, config);
+	}
+}
+
+struct pinconf_ops imx_pinconf_ops = {
+	.pin_config_get = imx_pinconf_get,
+	.pin_config_set = imx_pinconf_set,
+	.pin_config_dbg_show = imx_pinconf_dbg_show,
+	.pin_config_group_dbg_show = imx_pinconf_group_dbg_show,
+};
+
+static struct pinctrl_desc imx_pinctrl_desc = {
+	.pctlops = &imx_pctrl_ops,
+	.pmxops = &imx_pmx_ops,
+	.confops = &imx_pinconf_ops,
+	.owner = THIS_MODULE,
+};
+
+/* decode pin id and mux from pin function id got from device tree*/
+static int imx_pinctrl_get_pin_id_and_mux(const struct imx_pinctrl_soc_info *info,
+				unsigned int pin_func_id, unsigned int *pin_id,
+				unsigned int *mux)
+{
+	if (pin_func_id > info->npin_regs)
+		return -EINVAL;
+
+	*pin_id = info->pin_regs[pin_func_id].pid;
+	*mux = info->pin_regs[pin_func_id].mux_mode;
+
+	return 0;
+}
+
+static int __devinit imx_pinctrl_parse_groups(struct device_node *np,
+				struct imx_pin_group *grp,
+				struct imx_pinctrl_soc_info *info,
+				u32 index)
+{
+	unsigned int pin_func_id;
+	int ret, size;
+	const const __be32 *list;
+	int i, j;
+	u32 config;
+
+	dev_dbg(info->dev, "group(%d): %s\n", index, np->name);
+
+	/* Initialise group */
+	grp->name = np->name;
+
+	/*
+	 * the binding format is fsl,pins = <PIN_FUNC_ID CONFIG ...>,
+	 * do sanity check and calculate pins number
+	 */
+	list = of_get_property(np, "fsl,pins", &size);
+	/* we do not check return since it's safe node passed down */
+	size /= sizeof(*list);
+	if (!size || size % 2) {
+		dev_err(info->dev, "wrong pins number or pins and configs should be pairs\n");
+		return -EINVAL;
+	}
+
+	grp->npins = size / 2;
+	grp->pins = devm_kzalloc(info->dev, grp->npins * sizeof(unsigned int),
+				GFP_KERNEL);
+	grp->mux_mode = devm_kzalloc(info->dev, grp->npins * sizeof(unsigned int),
+				GFP_KERNEL);
+	grp->configs = devm_kzalloc(info->dev, grp->npins * sizeof(unsigned long),
+				GFP_KERNEL);
+	for (i = 0, j = 0; i < size; i += 2, j++) {
+		pin_func_id = be32_to_cpu(*list++);
+		ret = imx_pinctrl_get_pin_id_and_mux(info, pin_func_id,
+					&grp->pins[j], &grp->mux_mode[j]);
+		if (ret) {
+			dev_err(info->dev, "get invalid pin function id\n");
+			return -EINVAL;
+		}
+		/* SION bit is in mux register */
+		config = be32_to_cpu(*list++);
+		if (config & IMX_PAD_SION)
+			grp->mux_mode[j] |= IOMUXC_CONFIG_SION;
+		grp->configs[j] = config & ~IMX_PAD_SION;
+	}
+
+#ifdef DEBUG
+	IMX_PMX_DUMP(info, grp->pins, grp->mux_mode, grp->configs, grp->npins);
+#endif
+	return 0;
+}
+
+static int __devinit imx_pinctrl_parse_functions(struct device_node *np,
+			struct imx_pinctrl_soc_info *info, u32 index)
+{
+	struct device_node *child;
+	struct imx_pmx_func *func;
+	struct imx_pin_group *grp;
+	int ret;
+	static u32 grp_index;
+	u32 i = 0;
+
+	dev_dbg(info->dev, "parse function(%d): %s\n", index, np->name);
+
+	func = &info->functions[index];
+
+	/* Initialise function */
+	func->name = np->name;
+	func->num_groups = of_get_child_count(np);
+	if (func->num_groups <= 0) {
+		dev_err(info->dev, "no groups defined\n");
+		return -EINVAL;
+	}
+	func->groups = devm_kzalloc(info->dev,
+			func->num_groups * sizeof(char *), GFP_KERNEL);
+
+	for_each_child_of_node(np, child) {
+		func->groups[i] = child->name;
+		grp = &info->groups[grp_index++];
+		ret = imx_pinctrl_parse_groups(child, grp, info, i++);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int __devinit imx_pinctrl_probe_dt(struct platform_device *pdev,
+				struct imx_pinctrl_soc_info *info)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct device_node *child;
+	int ret;
+	u32 nfuncs = 0;
+	u32 i = 0;
+
+	if (!np)
+		return -ENODEV;
+
+	nfuncs = of_get_child_count(np);
+	if (nfuncs <= 0) {
+		dev_err(&pdev->dev, "no functions defined\n");
+		return -EINVAL;
+	}
+
+	info->nfunctions = nfuncs;
+	info->functions = devm_kzalloc(&pdev->dev, nfuncs * sizeof(struct imx_pmx_func),
+					GFP_KERNEL);
+	if (!info->functions)
+		return -ENOMEM;
+
+	info->ngroups = 0;
+	for_each_child_of_node(np, child)
+		info->ngroups += of_get_child_count(child);
+	info->groups = devm_kzalloc(&pdev->dev, info->ngroups * sizeof(struct imx_pin_group),
+					GFP_KERNEL);
+	if (!info->groups)
+		return -ENOMEM;
+
+	for_each_child_of_node(np, child) {
+		ret = imx_pinctrl_parse_functions(child, info, i++);
+		if (ret) {
+			dev_err(&pdev->dev, "failed to parse function\n");
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+int __devinit imx_pinctrl_probe(struct platform_device *pdev,
+				struct imx_pinctrl_soc_info *info)
+{
+	struct imx_pinctrl *ipctl;
+	struct resource *res;
+	int ret;
+
+	if (!info || !info->pins || !info->npins
+		  || !info->pin_regs || !info->npin_regs) {
+		dev_err(&pdev->dev, "wrong pinctrl info\n");
+		return -EINVAL;
+	}
+	info->dev = &pdev->dev;
+
+	/* Create state holders etc for this driver */
+	ipctl = devm_kzalloc(&pdev->dev, sizeof(*ipctl), GFP_KERNEL);
+	if (!ipctl)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENOENT;
+
+	ipctl->base = devm_request_and_ioremap(&pdev->dev, res);
+	if (!ipctl->base)
+		return -EBUSY;
+
+	imx_pinctrl_desc.name = dev_name(&pdev->dev);
+	imx_pinctrl_desc.pins = info->pins;
+	imx_pinctrl_desc.npins = info->npins;
+
+	ret = imx_pinctrl_probe_dt(pdev, info);
+	if (ret) {
+		dev_err(&pdev->dev, "fail to probe dt properties\n");
+		return ret;
+	}
+
+	ipctl->info = info;
+	ipctl->dev = info->dev;
+	platform_set_drvdata(pdev, ipctl);
+	ipctl->pctl = pinctrl_register(&imx_pinctrl_desc, &pdev->dev, ipctl);
+	if (!ipctl->pctl) {
+		dev_err(&pdev->dev, "could not register IMX pinctrl driver\n");
+		return -EINVAL;
+	}
+
+	dev_info(&pdev->dev, "initialized IMX pinctrl driver\n");
+
+	return 0;
+}
+
+int __devexit imx_pinctrl_remove(struct platform_device *pdev)
+{
+	struct imx_pinctrl *ipctl = platform_get_drvdata(pdev);
+
+	pinctrl_unregister(ipctl->pctl);
+
+	return 0;
+}