/*
   * Copyright (C) 2015-2016 Socionext Inc.
   *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */
  
  #include <common.h>
  #include <dm.h>
  #include <linux/io.h>
  #include <linux/err.h>
  #include <linux/kernel.h>
  #include <linux/sizes.h>
  #include <dm/pinctrl.h>
  
  #include "pinctrl-uniphier.h"
  
  #define UNIPHIER_PINCTRL_PINMUX_BASE	0x1000
  #define UNIPHIER_PINCTRL_LOAD_PINMUX	0x1700
  #define UNIPHIER_PINCTRL_PUPDCTRL_BASE	0x1a00
  #define UNIPHIER_PINCTRL_IECTRL		0x1d00
  
  static const char *uniphier_pinctrl_dummy_name = "_dummy";
  
  static int uniphier_pinctrl_get_groups_count(struct udevice *dev)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  
  	return priv->socdata->groups_count;
  }
  
  static const char *uniphier_pinctrl_get_group_name(struct udevice *dev,
  						   unsigned selector)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  
  	if (!priv->socdata->groups[selector].name)
  		return uniphier_pinctrl_dummy_name;
  
  	return priv->socdata->groups[selector].name;
  }
  
  static int uniphier_pinmux_get_functions_count(struct udevice *dev)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  
  	return priv->socdata->functions_count;
  }
  
  static const char *uniphier_pinmux_get_function_name(struct udevice *dev,
  						     unsigned selector)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  
  	if (!priv->socdata->functions[selector])
  		return uniphier_pinctrl_dummy_name;
  
  	return priv->socdata->functions[selector];
  }
  
  static int uniphier_pinconf_input_enable_perpin(struct udevice *dev,
  						unsigned int pin, int enable)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  	unsigned reg;
  	u32 mask, tmp;
  
  	reg = UNIPHIER_PINCTRL_IECTRL + pin / 32 * 4;
  	mask = BIT(pin % 32);
  
  	tmp = readl(priv->base + reg);
  	if (enable)
  		tmp |= mask;
  	else
  		tmp &= ~mask;
  	writel(tmp, priv->base + reg);
  
  	return 0;
  }
  
  static int uniphier_pinconf_input_enable_legacy(struct udevice *dev,
  						unsigned int pin, int enable)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  
  	/*
  	 * Multiple pins share one input enable, per-pin disabling is
  	 * impossible.
  	 */
  	if (!enable)
  		return -EINVAL;
  
  	/* Set all bits instead of having a bunch of pin data */
  	writel(U32_MAX, priv->base + UNIPHIER_PINCTRL_IECTRL);
  
  	return 0;
  }
  
  static int uniphier_pinconf_input_enable(struct udevice *dev,
  					 unsigned int pin, int enable)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  
  	if (priv->socdata->caps & UNIPHIER_PINCTRL_CAPS_PERPIN_IECTRL)
  		return uniphier_pinconf_input_enable_perpin(dev, pin, enable);
  	else
  		return uniphier_pinconf_input_enable_legacy(dev, pin, enable);
  }
  
  #if CONFIG_IS_ENABLED(PINCONF)
  
  static const struct pinconf_param uniphier_pinconf_params[] = {
  	{ "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 },
  	{ "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 },
  	{ "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 },
  	{ "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 1 },
  	{ "input-enable", PIN_CONFIG_INPUT_ENABLE, 1 },
  	{ "input-disable", PIN_CONFIG_INPUT_ENABLE, 0 },
  };
  
  static int uniphier_pinconf_bias_set(struct udevice *dev, unsigned int pin,
  				     unsigned int param, unsigned int arg)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  	unsigned int enable = 1;
  	unsigned int reg;
  	u32 mask, tmp;
  
  	if (!(priv->socdata->caps & UNIPHIER_PINCTRL_CAPS_PUPD_SIMPLE))
  		return -ENOTSUPP;
  
  	switch (param) {
  	case PIN_CONFIG_BIAS_DISABLE:
  		enable = 0;
  		break;
  	case PIN_CONFIG_BIAS_PULL_UP:
  	case PIN_CONFIG_BIAS_PULL_DOWN:
  		if (arg == 0)	/* total bias is not supported */
  			return -EINVAL;
  		break;
  	case PIN_CONFIG_BIAS_PULL_PIN_DEFAULT:
  		if (arg == 0)	/* configuration ignored */
  			return 0;
  	default:
  		BUG();
  	}
  
  	reg = UNIPHIER_PINCTRL_PUPDCTRL_BASE + pin / 32 * 4;
  	mask = BIT(pin % 32);
  
  	tmp = readl(priv->base + reg);
  	if (enable)
  		tmp |= mask;
  	else
  		tmp &= ~mask;
  	writel(tmp, priv->base + reg);
  
  	return 0;
  }
  
  static int uniphier_pinconf_set_one(struct udevice *dev, unsigned int pin,
  				    unsigned int param, unsigned int arg)
  {
  	int ret;
  
  	switch (param) {
  	case PIN_CONFIG_BIAS_DISABLE:
  	case PIN_CONFIG_BIAS_PULL_UP:
  	case PIN_CONFIG_BIAS_PULL_DOWN:
  	case PIN_CONFIG_BIAS_PULL_PIN_DEFAULT:
  		ret = uniphier_pinconf_bias_set(dev, pin, param, arg);
  		break;
  	case PIN_CONFIG_INPUT_ENABLE:
  		ret = uniphier_pinconf_input_enable(dev, pin, arg);
  		break;
  	default:
  		printf("unsupported configuration parameter %u
  ", param);
  		return -EINVAL;
  	}
  
  	return ret;
  }
  
  static int uniphier_pinconf_group_set(struct udevice *dev,
  				      unsigned int group_selector,
  				      unsigned int param, unsigned int arg)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  	const struct uniphier_pinctrl_group *grp =
  					&priv->socdata->groups[group_selector];
  	int i, ret;
  
  	for (i = 0; i < grp->num_pins; i++) {
  		ret = uniphier_pinconf_set_one(dev, grp->pins[i], param, arg);
  		if (ret)
  			return ret;
  	}
  
  	return 0;
  }
  
  #endif /* CONFIG_IS_ENABLED(PINCONF) */
  
  static void uniphier_pinmux_set_one(struct udevice *dev, unsigned pin,
  				    int muxval)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  	unsigned reg, reg_end, shift, mask;
  	unsigned mux_bits = 8;
  	unsigned reg_stride = 4;
  	bool load_pinctrl = false;
  	u32 tmp;
  
  	/* some pins need input-enabling */
  	uniphier_pinconf_input_enable(dev, pin, 1);
  
  	if (muxval < 0)
  		return;		/* dedicated pin; nothing to do for pin-mux */
  
  	if (priv->socdata->caps & UNIPHIER_PINCTRL_CAPS_MUX_4BIT)
  		mux_bits = 4;
  
  	if (priv->socdata->caps & UNIPHIER_PINCTRL_CAPS_DBGMUX_SEPARATE) {
  		/*
  		 *  Mode       offset        bit
  		 *  Normal     4 * n     shift+3:shift
  		 *  Debug      4 * n     shift+7:shift+4
  		 */
  		mux_bits /= 2;
  		reg_stride = 8;
  		load_pinctrl = true;
  	}
  
  	reg = UNIPHIER_PINCTRL_PINMUX_BASE + pin * mux_bits / 32 * reg_stride;
  	reg_end = reg + reg_stride;
  	shift = pin * mux_bits % 32;
  	mask = (1U << mux_bits) - 1;
  
  	/*
  	 * If reg_stride is greater than 4, the MSB of each pinsel shall be
  	 * stored in the offset+4.
  	 */
  	for (; reg < reg_end; reg += 4) {
  		tmp = readl(priv->base + reg);
  		tmp &= ~(mask << shift);
  		tmp |= (mask & muxval) << shift;
  		writel(tmp, priv->base + reg);
  
  		muxval >>= mux_bits;
  	}
  
  	if (load_pinctrl)
  		writel(1, priv->base + UNIPHIER_PINCTRL_LOAD_PINMUX);
  }
  
  static int uniphier_pinmux_group_set(struct udevice *dev,
  				     unsigned group_selector,
  				     unsigned func_selector)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  	const struct uniphier_pinctrl_group *grp =
  					&priv->socdata->groups[group_selector];
  	int i;
  
  	for (i = 0; i < grp->num_pins; i++)
  		uniphier_pinmux_set_one(dev, grp->pins[i], grp->muxvals[i]);
  
  	return 0;
  }
  
  const struct pinctrl_ops uniphier_pinctrl_ops = {
  	.get_groups_count = uniphier_pinctrl_get_groups_count,
  	.get_group_name = uniphier_pinctrl_get_group_name,
  	.get_functions_count = uniphier_pinmux_get_functions_count,
  	.get_function_name = uniphier_pinmux_get_function_name,
  	.pinmux_group_set = uniphier_pinmux_group_set,
  #if CONFIG_IS_ENABLED(PINCONF)
  	.pinconf_num_params = ARRAY_SIZE(uniphier_pinconf_params),
  	.pinconf_params = uniphier_pinconf_params,
  	.pinconf_group_set = uniphier_pinconf_group_set,
  #endif
  	.set_state = pinctrl_generic_set_state,
  };
  
  int uniphier_pinctrl_probe(struct udevice *dev,
  			   struct uniphier_pinctrl_socdata *socdata)
  {
  	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
  	fdt_addr_t addr;
  
  	addr = devfdt_get_addr(dev->parent);
  	if (addr == FDT_ADDR_T_NONE)
  		return -EINVAL;
  
  	priv->base = devm_ioremap(dev, addr, SZ_4K);
  	if (!priv->base)
  		return -ENOMEM;
  
  	priv->socdata = socdata;
  
  	return 0;
  }