1 files changed, 492 insertions, 0 deletions

diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c
new file mode 100644
index 000000000000..30f3316747e2
--- /dev/null
+++ b/drivers/pinctrl/mediatek/mtk-eint.c
@@ -0,0 +1,492 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2014-2018 MediaTek Inc.
+
+/*
+ * Library for MediaTek External Interrupt Support
+ *
+ * Author: Maoguang Meng <maoguang.meng@mediatek.com>
+ *	   Sean Wang <sean.wang@mediatek.com>
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+
+#include "mtk-eint.h"
+
+#define MTK_EINT_EDGE_SENSITIVE           0
+#define MTK_EINT_LEVEL_SENSITIVE          1
+#define MTK_EINT_DBNC_SET_DBNC_BITS	  4
+#define MTK_EINT_DBNC_RST_BIT		  (0x1 << 1)
+#define MTK_EINT_DBNC_SET_EN		  (0x1 << 0)
+
+static const struct mtk_eint_regs mtk_generic_eint_regs = {
+	.stat      = 0x000,
+	.ack       = 0x040,
+	.mask      = 0x080,
+	.mask_set  = 0x0c0,
+	.mask_clr  = 0x100,
+	.sens      = 0x140,
+	.sens_set  = 0x180,
+	.sens_clr  = 0x1c0,
+	.soft      = 0x200,
+	.soft_set  = 0x240,
+	.soft_clr  = 0x280,
+	.pol       = 0x300,
+	.pol_set   = 0x340,
+	.pol_clr   = 0x380,
+	.dom_en    = 0x400,
+	.dbnc_ctrl = 0x500,
+	.dbnc_set  = 0x600,
+	.dbnc_clr  = 0x700,
+};
+
+static void __iomem *mtk_eint_get_offset(struct mtk_eint *eint,
+					 unsigned int eint_num,
+					 unsigned int offset)
+{
+	unsigned int eint_base = 0;
+	void __iomem *reg;
+
+	if (eint_num >= eint->hw->ap_num)
+		eint_base = eint->hw->ap_num;
+
+	reg = eint->base + offset + ((eint_num - eint_base) / 32) * 4;
+
+	return reg;
+}
+
+static unsigned int mtk_eint_can_en_debounce(struct mtk_eint *eint,
+					     unsigned int eint_num)
+{
+	unsigned int sens;
+	unsigned int bit = BIT(eint_num % 32);
+	void __iomem *reg = mtk_eint_get_offset(eint, eint_num,
+						eint->regs->sens);
+
+	if (readl(reg) & bit)
+		sens = MTK_EINT_LEVEL_SENSITIVE;
+	else
+		sens = MTK_EINT_EDGE_SENSITIVE;
+
+	if (eint_num < eint->hw->db_cnt && sens != MTK_EINT_EDGE_SENSITIVE)
+		return 1;
+	else
+		return 0;
+}
+
+static int mtk_eint_flip_edge(struct mtk_eint *eint, int hwirq)
+{
+	int start_level, curr_level;
+	unsigned int reg_offset;
+	u32 mask = BIT(hwirq & 0x1f);
+	u32 port = (hwirq >> 5) & eint->hw->port_mask;
+	void __iomem *reg = eint->base + (port << 2);
+
+	curr_level = eint->gpio_xlate->get_gpio_state(eint->pctl, hwirq);
+
+	do {
+		start_level = curr_level;
+		if (start_level)
+			reg_offset = eint->regs->pol_clr;
+		else
+			reg_offset = eint->regs->pol_set;
+		writel(mask, reg + reg_offset);
+
+		curr_level = eint->gpio_xlate->get_gpio_state(eint->pctl,
+							      hwirq);
+	} while (start_level != curr_level);
+
+	return start_level;
+}
+
+static void mtk_eint_mask(struct irq_data *d)
+{
+	struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
+	u32 mask = BIT(d->hwirq & 0x1f);
+	void __iomem *reg = mtk_eint_get_offset(eint, d->hwirq,
+						eint->regs->mask_set);
+
+	writel(mask, reg);
+}
+
+static void mtk_eint_unmask(struct irq_data *d)
+{
+	struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
+	u32 mask = BIT(d->hwirq & 0x1f);
+	void __iomem *reg = mtk_eint_get_offset(eint, d->hwirq,
+						eint->regs->mask_clr);
+
+	writel(mask, reg);
+
+	if (eint->dual_edge[d->hwirq])
+		mtk_eint_flip_edge(eint, d->hwirq);
+}
+
+static unsigned int mtk_eint_get_mask(struct mtk_eint *eint,
+				      unsigned int eint_num)
+{
+	unsigned int bit = BIT(eint_num % 32);
+	void __iomem *reg = mtk_eint_get_offset(eint, eint_num,
+						eint->regs->mask);
+
+	return !!(readl(reg) & bit);
+}
+
+static void mtk_eint_ack(struct irq_data *d)
+{
+	struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
+	u32 mask = BIT(d->hwirq & 0x1f);
+	void __iomem *reg = mtk_eint_get_offset(eint, d->hwirq,
+						eint->regs->ack);
+
+	writel(mask, reg);
+}
+
+static int mtk_eint_set_type(struct irq_data *d, unsigned int type)
+{
+	struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
+	u32 mask = BIT(d->hwirq & 0x1f);
+	void __iomem *reg;
+
+	if (((type & IRQ_TYPE_EDGE_BOTH) && (type & IRQ_TYPE_LEVEL_MASK)) ||
+	    ((type & IRQ_TYPE_LEVEL_MASK) == IRQ_TYPE_LEVEL_MASK)) {
+		dev_err(eint->dev,
+			"Can't configure IRQ%d (EINT%lu) for type 0x%X\n",
+			d->irq, d->hwirq, type);
+		return -EINVAL;
+	}
+
+	if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH)
+		eint->dual_edge[d->hwirq] = 1;
+	else
+		eint->dual_edge[d->hwirq] = 0;
+
+	if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING)) {
+		reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->pol_clr);
+		writel(mask, reg);
+	} else {
+		reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->pol_set);
+		writel(mask, reg);
+	}
+
+	if (type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING)) {
+		reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->sens_clr);
+		writel(mask, reg);
+	} else {
+		reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->sens_set);
+		writel(mask, reg);
+	}
+
+	if (eint->dual_edge[d->hwirq])
+		mtk_eint_flip_edge(eint, d->hwirq);
+
+	return 0;
+}
+
+static int mtk_eint_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+	struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
+	int shift = d->hwirq & 0x1f;
+	int reg = d->hwirq >> 5;
+
+	if (on)
+		eint->wake_mask[reg] |= BIT(shift);
+	else
+		eint->wake_mask[reg] &= ~BIT(shift);
+
+	return 0;
+}
+
+static void mtk_eint_chip_write_mask(const struct mtk_eint *eint,
+				     void __iomem *base, u32 *buf)
+{
+	int port;
+	void __iomem *reg;
+
+	for (port = 0; port < eint->hw->ports; port++) {
+		reg = base + (port << 2);
+		writel_relaxed(~buf[port], reg + eint->regs->mask_set);
+		writel_relaxed(buf[port], reg + eint->regs->mask_clr);
+	}
+}
+
+static void mtk_eint_chip_read_mask(const struct mtk_eint *eint,
+				    void __iomem *base, u32 *buf)
+{
+	int port;
+	void __iomem *reg;
+
+	for (port = 0; port < eint->hw->ports; port++) {
+		reg = base + eint->regs->mask + (port << 2);
+		buf[port] = ~readl_relaxed(reg);
+		/* Mask is 0 when irq is enabled, and 1 when disabled. */
+	}
+}
+
+static int mtk_eint_irq_request_resources(struct irq_data *d)
+{
+	struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
+	struct gpio_chip *gpio_c;
+	unsigned int gpio_n;
+	int err;
+
+	err = eint->gpio_xlate->get_gpio_n(eint->pctl, d->hwirq,
+					   &gpio_n, &gpio_c);
+	if (err < 0) {
+		dev_err(eint->dev, "Can not find pin\n");
+		return err;
+	}
+
+	err = gpiochip_lock_as_irq(gpio_c, gpio_n);
+	if (err < 0) {
+		dev_err(eint->dev, "unable to lock HW IRQ %lu for IRQ\n",
+			irqd_to_hwirq(d));
+		return err;
+	}
+
+	err = eint->gpio_xlate->set_gpio_as_eint(eint->pctl, d->hwirq);
+	if (err < 0) {
+		dev_err(eint->dev, "Can not eint mode\n");
+		return err;
+	}
+
+	return 0;
+}
+
+static void mtk_eint_irq_release_resources(struct irq_data *d)
+{
+	struct mtk_eint *eint = irq_data_get_irq_chip_data(d);
+	struct gpio_chip *gpio_c;
+	unsigned int gpio_n;
+
+	eint->gpio_xlate->get_gpio_n(eint->pctl, d->hwirq, &gpio_n,
+				     &gpio_c);
+
+	gpiochip_unlock_as_irq(gpio_c, gpio_n);
+}
+
+static struct irq_chip mtk_eint_irq_chip = {
+	.name = "mt-eint",
+	.irq_disable = mtk_eint_mask,
+	.irq_mask = mtk_eint_mask,
+	.irq_unmask = mtk_eint_unmask,
+	.irq_ack = mtk_eint_ack,
+	.irq_set_type = mtk_eint_set_type,
+	.irq_set_wake = mtk_eint_irq_set_wake,
+	.irq_request_resources = mtk_eint_irq_request_resources,
+	.irq_release_resources = mtk_eint_irq_release_resources,
+};
+
+static unsigned int mtk_eint_hw_init(struct mtk_eint *eint)
+{
+	void __iomem *reg = eint->base + eint->regs->dom_en;
+	unsigned int i;
+
+	for (i = 0; i < eint->hw->ap_num; i += 32) {
+		writel(0xffffffff, reg);
+		reg += 4;
+	}
+
+	return 0;
+}
+
+static inline void
+mtk_eint_debounce_process(struct mtk_eint *eint, int index)
+{
+	unsigned int rst, ctrl_offset;
+	unsigned int bit, dbnc;
+
+	ctrl_offset = (index / 4) * 4 + eint->regs->dbnc_ctrl;
+	dbnc = readl(eint->base + ctrl_offset);
+	bit = MTK_EINT_DBNC_SET_EN << ((index % 4) * 8);
+	if ((bit & dbnc) > 0) {
+		ctrl_offset = (index / 4) * 4 + eint->regs->dbnc_set;
+		rst = MTK_EINT_DBNC_RST_BIT << ((index % 4) * 8);
+		writel(rst, eint->base + ctrl_offset);
+	}
+}
+
+static void mtk_eint_irq_handler(struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	struct mtk_eint *eint = irq_desc_get_handler_data(desc);
+	unsigned int status, eint_num;
+	int offset, index, virq;
+	void __iomem *reg =  mtk_eint_get_offset(eint, 0, eint->regs->stat);
+	int dual_edge, start_level, curr_level;
+
+	chained_irq_enter(chip, desc);
+	for (eint_num = 0; eint_num < eint->hw->ap_num; eint_num += 32,
+	     reg += 4) {
+		status = readl(reg);
+		while (status) {
+			offset = __ffs(status);
+			index = eint_num + offset;
+			virq = irq_find_mapping(eint->domain, index);
+			status &= ~BIT(offset);
+
+			dual_edge = eint->dual_edge[index];
+			if (dual_edge) {
+				/*
+				 * Clear soft-irq in case we raised it last
+				 * time.
+				 */
+				writel(BIT(offset), reg - eint->regs->stat +
+				       eint->regs->soft_clr);
+
+				start_level =
+				eint->gpio_xlate->get_gpio_state(eint->pctl,
+								 index);
+			}
+
+			generic_handle_irq(virq);
+
+			if (dual_edge) {
+				curr_level = mtk_eint_flip_edge(eint, index);
+
+				/*
+				 * If level changed, we might lost one edge
+				 * interrupt, raised it through soft-irq.
+				 */
+				if (start_level != curr_level)
+					writel(BIT(offset), reg -
+					       eint->regs->stat +
+					       eint->regs->soft_set);
+			}
+
+			if (index < eint->hw->db_cnt)
+				mtk_eint_debounce_process(eint, index);
+		}
+	}
+	chained_irq_exit(chip, desc);
+}
+
+int mtk_eint_do_suspend(struct mtk_eint *eint)
+{
+	mtk_eint_chip_read_mask(eint, eint->base, eint->cur_mask);
+	mtk_eint_chip_write_mask(eint, eint->base, eint->wake_mask);
+
+	return 0;
+}
+
+int mtk_eint_do_resume(struct mtk_eint *eint)
+{
+	mtk_eint_chip_write_mask(eint, eint->base, eint->cur_mask);
+
+	return 0;
+}
+
+int mtk_eint_set_debounce(struct mtk_eint *eint, unsigned long eint_num,
+			  unsigned int debounce)
+{
+	int virq, eint_offset;
+	unsigned int set_offset, bit, clr_bit, clr_offset, rst, i, unmask,
+		     dbnc;
+	static const unsigned int debounce_time[] = {500, 1000, 16000, 32000,
+						     64000, 128000, 256000};
+	struct irq_data *d;
+
+	virq = irq_find_mapping(eint->domain, eint_num);
+	eint_offset = (eint_num % 4) * 8;
+	d = irq_get_irq_data(virq);
+
+	set_offset = (eint_num / 4) * 4 + eint->regs->dbnc_set;
+	clr_offset = (eint_num / 4) * 4 + eint->regs->dbnc_clr;
+
+	if (!mtk_eint_can_en_debounce(eint, eint_num))
+		return -EINVAL;
+
+	dbnc = ARRAY_SIZE(debounce_time);
+	for (i = 0; i < ARRAY_SIZE(debounce_time); i++) {
+		if (debounce <= debounce_time[i]) {
+			dbnc = i;
+			break;
+		}
+	}
+
+	if (!mtk_eint_get_mask(eint, eint_num)) {
+		mtk_eint_mask(d);
+		unmask = 1;
+	} else {
+		unmask = 0;
+	}
+
+	clr_bit = 0xff << eint_offset;
+	writel(clr_bit, eint->base + clr_offset);
+
+	bit = ((dbnc << MTK_EINT_DBNC_SET_DBNC_BITS) | MTK_EINT_DBNC_SET_EN) <<
+		eint_offset;
+	rst = MTK_EINT_DBNC_RST_BIT << eint_offset;
+	writel(rst | bit, eint->base + set_offset);
+
+	/*
+	 * Delay a while (more than 2T) to wait for hw debounce counter reset
+	 * work correctly.
+	 */
+	udelay(1);
+	if (unmask == 1)
+		mtk_eint_unmask(d);
+
+	return 0;
+}
+
+int mtk_eint_find_irq(struct mtk_eint *eint, unsigned long eint_n)
+{
+	int irq;
+
+	irq = irq_find_mapping(eint->domain, eint_n);
+	if (!irq)
+		return -EINVAL;
+
+	return irq;
+}
+
+int mtk_eint_do_init(struct mtk_eint *eint)
+{
+	int i;
+
+	/* If clients don't assign a specific regs, let's use generic one */
+	if (!eint->regs)
+		eint->regs = &mtk_generic_eint_regs;
+
+	eint->wake_mask = devm_kcalloc(eint->dev, eint->hw->ports,
+				       sizeof(*eint->wake_mask), GFP_KERNEL);
+	if (!eint->wake_mask)
+		return -ENOMEM;
+
+	eint->cur_mask = devm_kcalloc(eint->dev, eint->hw->ports,
+				      sizeof(*eint->cur_mask), GFP_KERNEL);
+	if (!eint->cur_mask)
+		return -ENOMEM;
+
+	eint->dual_edge = devm_kcalloc(eint->dev, eint->hw->ap_num,
+				       sizeof(int), GFP_KERNEL);
+	if (!eint->dual_edge)
+		return -ENOMEM;
+
+	eint->domain = irq_domain_add_linear(eint->dev->of_node,
+					     eint->hw->ap_num,
+					     &irq_domain_simple_ops, NULL);
+	if (!eint->domain)
+		return -ENOMEM;
+
+	mtk_eint_hw_init(eint);
+	for (i = 0; i < eint->hw->ap_num; i++) {
+		int virq = irq_create_mapping(eint->domain, i);
+
+		irq_set_chip_and_handler(virq, &mtk_eint_irq_chip,
+					 handle_level_irq);
+		irq_set_chip_data(virq, eint);
+	}
+
+	irq_set_chained_handler_and_data(eint->irq, mtk_eint_irq_handler,
+					 eint);
+
+	return 0;
+}