diff options
Diffstat (limited to 'drivers/pinctrl/mediatek/mtk-eint.c')
| -rw-r--r-- | drivers/pinctrl/mediatek/mtk-eint.c | 509 |
1 files changed, 509 insertions, 0 deletions
diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c new file mode 100644 index 000000000..64a32d3ca --- /dev/null +++ b/drivers/pinctrl/mediatek/mtk-eint.c @@ -0,0 +1,509 @@ +// 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/driver.h> +#include <linux/io.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/module.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); + + eint->cur_mask[d->hwirq >> 5] &= ~mask; + + 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); + + eint->cur_mask[d->hwirq >> 5] |= mask; + + 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 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 *dom_en = eint->base + eint->regs->dom_en; + void __iomem *mask_set = eint->base + eint->regs->mask_set; + unsigned int i; + + for (i = 0; i < eint->hw->ap_num; i += 32) { + writel(0xffffffff, dom_en); + writel(0xffffffff, mask_set); + dom_en += 4; + mask_set += 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, mask_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); + mask_offset = eint_num >> 5; + index = eint_num + offset; + virq = irq_find_mapping(eint->domain, index); + status &= ~BIT(offset); + + /* + * If we get an interrupt on pin that was only required + * for wake (but no real interrupt requested), mask the + * interrupt (as would mtk_eint_resume do anyway later + * in the resume sequence). + */ + if (eint->wake_mask[mask_offset] & BIT(offset) && + !(eint->cur_mask[mask_offset] & BIT(offset))) { + writel_relaxed(BIT(offset), reg - + eint->regs->stat + + eint->regs->mask_set); + } + + 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_write_mask(eint, eint->base, eint->wake_mask); + + return 0; +} +EXPORT_SYMBOL_GPL(mtk_eint_do_suspend); + +int mtk_eint_do_resume(struct mtk_eint *eint) +{ + mtk_eint_chip_write_mask(eint, eint->base, eint->cur_mask); + + return 0; +} +EXPORT_SYMBOL_GPL(mtk_eint_do_resume); + +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; +} +EXPORT_SYMBOL_GPL(mtk_eint_set_debounce); + +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; +} +EXPORT_SYMBOL_GPL(mtk_eint_find_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; +} +EXPORT_SYMBOL_GPL(mtk_eint_do_init); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("MediaTek EINT Driver"); |