/* * Copyright 2015 IBM Corp. * * Joel Stanley * * 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 #include #include #include #include #include #include #include #include #include #include #include struct aspeed_bank_props { unsigned int bank; u32 input; u32 output; }; struct aspeed_gpio_config { unsigned int nr_gpios; const struct aspeed_bank_props *props; }; /* * @offset_timer: Maps an offset to an @timer_users index, or zero if disabled * @timer_users: Tracks the number of users for each timer * * The @timer_users has four elements but the first element is unused. This is * to simplify accounting and indexing, as a zero value in @offset_timer * represents disabled debouncing for the GPIO. Any other value for an element * of @offset_timer is used as an index into @timer_users. This behaviour of * the zero value aligns with the behaviour of zero built from the timer * configuration registers (i.e. debouncing is disabled). */ struct aspeed_gpio { struct gpio_chip chip; spinlock_t lock; void __iomem *base; int irq; const struct aspeed_gpio_config *config; u8 *offset_timer; unsigned int timer_users[4]; struct clk *clk; }; struct aspeed_gpio_bank { uint16_t val_regs; uint16_t irq_regs; uint16_t debounce_regs; const char names[4][3]; }; static const int debounce_timers[4] = { 0x00, 0x50, 0x54, 0x58 }; static const struct aspeed_gpio_bank aspeed_gpio_banks[] = { { .val_regs = 0x0000, .irq_regs = 0x0008, .debounce_regs = 0x0040, .names = { "A", "B", "C", "D" }, }, { .val_regs = 0x0020, .irq_regs = 0x0028, .debounce_regs = 0x0048, .names = { "E", "F", "G", "H" }, }, { .val_regs = 0x0070, .irq_regs = 0x0098, .debounce_regs = 0x00b0, .names = { "I", "J", "K", "L" }, }, { .val_regs = 0x0078, .irq_regs = 0x00e8, .debounce_regs = 0x0100, .names = { "M", "N", "O", "P" }, }, { .val_regs = 0x0080, .irq_regs = 0x0118, .debounce_regs = 0x0130, .names = { "Q", "R", "S", "T" }, }, { .val_regs = 0x0088, .irq_regs = 0x0148, .debounce_regs = 0x0160, .names = { "U", "V", "W", "X" }, }, { .val_regs = 0x01E0, .irq_regs = 0x0178, .debounce_regs = 0x0190, .names = { "Y", "Z", "AA", "AB" }, }, { .val_regs = 0x01E8, .irq_regs = 0x01A8, .debounce_regs = 0x01c0, .names = { "AC", "", "", "" }, }, }; #define GPIO_BANK(x) ((x) >> 5) #define GPIO_OFFSET(x) ((x) & 0x1f) #define GPIO_BIT(x) BIT(GPIO_OFFSET(x)) #define GPIO_DATA 0x00 #define GPIO_DIR 0x04 #define GPIO_IRQ_ENABLE 0x00 #define GPIO_IRQ_TYPE0 0x04 #define GPIO_IRQ_TYPE1 0x08 #define GPIO_IRQ_TYPE2 0x0c #define GPIO_IRQ_STATUS 0x10 #define GPIO_DEBOUNCE_SEL1 0x00 #define GPIO_DEBOUNCE_SEL2 0x04 #define _GPIO_SET_DEBOUNCE(t, o, i) ((!!((t) & BIT(i))) << GPIO_OFFSET(o)) #define GPIO_SET_DEBOUNCE1(t, o) _GPIO_SET_DEBOUNCE(t, o, 1) #define GPIO_SET_DEBOUNCE2(t, o) _GPIO_SET_DEBOUNCE(t, o, 0) static const struct aspeed_gpio_bank *to_bank(unsigned int offset) { unsigned int bank = GPIO_BANK(offset); WARN_ON(bank > ARRAY_SIZE(aspeed_gpio_banks)); return &aspeed_gpio_banks[bank]; } static inline bool is_bank_props_sentinel(const struct aspeed_bank_props *props) { return !(props->input || props->output); } static inline const struct aspeed_bank_props *find_bank_props( struct aspeed_gpio *gpio, unsigned int offset) { const struct aspeed_bank_props *props = gpio->config->props; while (!is_bank_props_sentinel(props)) { if (props->bank == GPIO_BANK(offset)) return props; props++; } return NULL; } static inline bool have_gpio(struct aspeed_gpio *gpio, unsigned int offset) { const struct aspeed_bank_props *props = find_bank_props(gpio, offset); const struct aspeed_gpio_bank *bank = to_bank(offset); unsigned int group = GPIO_OFFSET(offset) / 8; return bank->names[group][0] != '\0' && (!props || ((props->input | props->output) & GPIO_BIT(offset))); } static inline bool have_input(struct aspeed_gpio *gpio, unsigned int offset) { const struct aspeed_bank_props *props = find_bank_props(gpio, offset); return !props || (props->input & GPIO_BIT(offset)); } #define have_irq(g, o) have_input((g), (o)) #define have_debounce(g, o) have_input((g), (o)) static inline bool have_output(struct aspeed_gpio *gpio, unsigned int offset) { const struct aspeed_bank_props *props = find_bank_props(gpio, offset); return !props || (props->output & GPIO_BIT(offset)); } static void __iomem *bank_val_reg(struct aspeed_gpio *gpio, const struct aspeed_gpio_bank *bank, unsigned int reg) { return gpio->base + bank->val_regs + reg; } static void __iomem *bank_irq_reg(struct aspeed_gpio *gpio, const struct aspeed_gpio_bank *bank, unsigned int reg) { return gpio->base + bank->irq_regs + reg; } static int aspeed_gpio_get(struct gpio_chip *gc, unsigned int offset) { struct aspeed_gpio *gpio = gpiochip_get_data(gc); const struct aspeed_gpio_bank *bank = to_bank(offset); return !!(ioread32(bank_val_reg(gpio, bank, GPIO_DATA)) & GPIO_BIT(offset)); } static void __aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset, int val) { struct aspeed_gpio *gpio = gpiochip_get_data(gc); const struct aspeed_gpio_bank *bank = to_bank(offset); void __iomem *addr; u32 reg; addr = bank_val_reg(gpio, bank, GPIO_DATA); reg = ioread32(addr); if (val) reg |= GPIO_BIT(offset); else reg &= ~GPIO_BIT(offset); iowrite32(reg, addr); } static void aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset, int val) { struct aspeed_gpio *gpio = gpiochip_get_data(gc); unsigned long flags; spin_lock_irqsave(&gpio->lock, flags); __aspeed_gpio_set(gc, offset, val); spin_unlock_irqrestore(&gpio->lock, flags); } static int aspeed_gpio_dir_in(struct gpio_chip *gc, unsigned int offset) { struct aspeed_gpio *gpio = gpiochip_get_data(gc); const struct aspeed_gpio_bank *bank = to_bank(offset); unsigned long flags; u32 reg; if (!have_input(gpio, offset)) return -ENOTSUPP; spin_lock_irqsave(&gpio->lock, flags); reg = ioread32(bank_val_reg(gpio, bank, GPIO_DIR)); iowrite32(reg & ~GPIO_BIT(offset), bank_val_reg(gpio, bank, GPIO_DIR)); spin_unlock_irqrestore(&gpio->lock, flags); return 0; } static int aspeed_gpio_dir_out(struct gpio_chip *gc, unsigned int offset, int val) { struct aspeed_gpio *gpio = gpiochip_get_data(gc); const struct aspeed_gpio_bank *bank = to_bank(offset); unsigned long flags; u32 reg; if (!have_output(gpio, offset)) return -ENOTSUPP; spin_lock_irqsave(&gpio->lock, flags); reg = ioread32(bank_val_reg(gpio, bank, GPIO_DIR)); iowrite32(reg | GPIO_BIT(offset), bank_val_reg(gpio, bank, GPIO_DIR)); __aspeed_gpio_set(gc, offset, val); spin_unlock_irqrestore(&gpio->lock, flags); return 0; } static int aspeed_gpio_get_direction(struct gpio_chip *gc, unsigned int offset) { struct aspeed_gpio *gpio = gpiochip_get_data(gc); const struct aspeed_gpio_bank *bank = to_bank(offset); unsigned long flags; u32 val; if (!have_input(gpio, offset)) return 0; if (!have_output(gpio, offset)) return 1; spin_lock_irqsave(&gpio->lock, flags); val = ioread32(bank_val_reg(gpio, bank, GPIO_DIR)) & GPIO_BIT(offset); spin_unlock_irqrestore(&gpio->lock, flags); return !val; } static inline int irqd_to_aspeed_gpio_data(struct irq_data *d, struct aspeed_gpio **gpio, const struct aspeed_gpio_bank **bank, u32 *bit) { int offset; struct aspeed_gpio *internal; offset = irqd_to_hwirq(d); internal = irq_data_get_irq_chip_data(d); /* This might be a bit of a questionable place to check */ if (!have_irq(internal, offset)) return -ENOTSUPP; *gpio = internal; *bank = to_bank(offset); *bit = GPIO_BIT(offset); return 0; } static void aspeed_gpio_irq_ack(struct irq_data *d) { const struct aspeed_gpio_bank *bank; struct aspeed_gpio *gpio; unsigned long flags; void __iomem *status_addr; u32 bit; int rc; rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit); if (rc) return; status_addr = bank_irq_reg(gpio, bank, GPIO_IRQ_STATUS); spin_lock_irqsave(&gpio->lock, flags); iowrite32(bit, status_addr); spin_unlock_irqrestore(&gpio->lock, flags); } static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set) { const struct aspeed_gpio_bank *bank; struct aspeed_gpio *gpio; unsigned long flags; u32 reg, bit; void __iomem *addr; int rc; rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit); if (rc) return; addr = bank_irq_reg(gpio, bank, GPIO_IRQ_ENABLE); spin_lock_irqsave(&gpio->lock, flags); reg = ioread32(addr); if (set) reg |= bit; else reg &= bit; iowrite32(reg, addr); spin_unlock_irqrestore(&gpio->lock, flags); } static void aspeed_gpio_irq_mask(struct irq_data *d) { aspeed_gpio_irq_set_mask(d, false); } static void aspeed_gpio_irq_unmask(struct irq_data *d) { aspeed_gpio_irq_set_mask(d, true); } static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type) { u32 type0 = 0; u32 type1 = 0; u32 type2 = 0; u32 bit, reg; const struct aspeed_gpio_bank *bank; irq_flow_handler_t handler; struct aspeed_gpio *gpio; unsigned long flags; void __iomem *addr; int rc; rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit); if (rc) return -EINVAL; switch (type & IRQ_TYPE_SENSE_MASK) { case IRQ_TYPE_EDGE_BOTH: type2 |= bit; /* fall through */ case IRQ_TYPE_EDGE_RISING: type0 |= bit; /* fall through */ case IRQ_TYPE_EDGE_FALLING: handler = handle_edge_irq; break; case IRQ_TYPE_LEVEL_HIGH: type0 |= bit; /* fall through */ case IRQ_TYPE_LEVEL_LOW: type1 |= bit; handler = handle_level_irq; break; default: return -EINVAL; } spin_lock_irqsave(&gpio->lock, flags); addr = bank_irq_reg(gpio, bank, GPIO_IRQ_TYPE0); reg = ioread32(addr); reg = (reg & ~bit) | type0; iowrite32(reg, addr); addr = bank_irq_reg(gpio, bank, GPIO_IRQ_TYPE1); reg = ioread32(addr); reg = (reg & ~bit) | type1; iowrite32(reg, addr); addr = bank_irq_reg(gpio, bank, GPIO_IRQ_TYPE2); reg = ioread32(addr); reg = (reg & ~bit) | type2; iowrite32(reg, addr); spin_unlock_irqrestore(&gpio->lock, flags); irq_set_handler_locked(d, handler); return 0; } static void aspeed_gpio_irq_handler(struct irq_desc *desc) { struct gpio_chip *gc = irq_desc_get_handler_data(desc); struct irq_chip *ic = irq_desc_get_chip(desc); struct aspeed_gpio *data = gpiochip_get_data(gc); unsigned int i, p, girq; unsigned long reg; chained_irq_enter(ic, desc); for (i = 0; i < ARRAY_SIZE(aspeed_gpio_banks); i++) { const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i]; reg = ioread32(bank_irq_reg(data, bank, GPIO_IRQ_STATUS)); for_each_set_bit(p, ®, 32) { girq = irq_find_mapping(gc->irq.domain, i * 32 + p); generic_handle_irq(girq); } } chained_irq_exit(ic, desc); } static struct irq_chip aspeed_gpio_irqchip = { .name = "aspeed-gpio", .irq_ack = aspeed_gpio_irq_ack, .irq_mask = aspeed_gpio_irq_mask, .irq_unmask = aspeed_gpio_irq_unmask, .irq_set_type = aspeed_gpio_set_type, }; static void set_irq_valid_mask(struct aspeed_gpio *gpio) { const struct aspeed_bank_props *props = gpio->config->props; while (!is_bank_props_sentinel(props)) { unsigned int offset; const unsigned long int input = props->input; /* Pretty crummy approach, but similar to GPIO core */ for_each_clear_bit(offset, &input, 32) { unsigned int i = props->bank * 32 + offset; if (i >= gpio->config->nr_gpios) break; clear_bit(i, gpio->chip.irq_valid_mask); } props++; } } static int aspeed_gpio_setup_irqs(struct aspeed_gpio *gpio, struct platform_device *pdev) { int rc; rc = platform_get_irq(pdev, 0); if (rc < 0) return rc; gpio->irq = rc; set_irq_valid_mask(gpio); rc = gpiochip_irqchip_add(&gpio->chip, &aspeed_gpio_irqchip, 0, handle_bad_irq, IRQ_TYPE_NONE); if (rc) { dev_info(&pdev->dev, "Could not add irqchip\n"); return rc; } gpiochip_set_chained_irqchip(&gpio->chip, &aspeed_gpio_irqchip, gpio->irq, aspeed_gpio_irq_handler); return 0; } static int aspeed_gpio_request(struct gpio_chip *chip, unsigned int offset) { if (!have_gpio(gpiochip_get_data(chip), offset)) return -ENODEV; return pinctrl_request_gpio(chip->base + offset); } static void aspeed_gpio_free(struct gpio_chip *chip, unsigned int offset) { pinctrl_free_gpio(chip->base + offset); } static inline void __iomem *bank_debounce_reg(struct aspeed_gpio *gpio, const struct aspeed_gpio_bank *bank, unsigned int reg) { return gpio->base + bank->debounce_regs + reg; } static int usecs_to_cycles(struct aspeed_gpio *gpio, unsigned long usecs, u32 *cycles) { u64 rate; u64 n; u32 r; rate = clk_get_rate(gpio->clk); if (!rate) return -ENOTSUPP; n = rate * usecs; r = do_div(n, 1000000); if (n >= U32_MAX) return -ERANGE; /* At least as long as the requested time */ *cycles = n + (!!r); return 0; } /* Call under gpio->lock */ static int register_allocated_timer(struct aspeed_gpio *gpio, unsigned int offset, unsigned int timer) { if (WARN(gpio->offset_timer[offset] != 0, "Offset %d already allocated timer %d\n", offset, gpio->offset_timer[offset])) return -EINVAL; if (WARN(gpio->timer_users[timer] == UINT_MAX, "Timer user count would overflow\n")) return -EPERM; gpio->offset_timer[offset] = timer; gpio->timer_users[timer]++; return 0; } /* Call under gpio->lock */ static int unregister_allocated_timer(struct aspeed_gpio *gpio, unsigned int offset) { if (WARN(gpio->offset_timer[offset] == 0, "No timer allocated to offset %d\n", offset)) return -EINVAL; if (WARN(gpio->timer_users[gpio->offset_timer[offset]] == 0, "No users recorded for timer %d\n", gpio->offset_timer[offset])) return -EINVAL; gpio->timer_users[gpio->offset_timer[offset]]--; gpio->offset_timer[offset] = 0; return 0; } /* Call under gpio->lock */ static inline bool timer_allocation_registered(struct aspeed_gpio *gpio, unsigned int offset) { return gpio->offset_timer[offset] > 0; } /* Call under gpio->lock */ static void configure_timer(struct aspeed_gpio *gpio, unsigned int offset, unsigned int timer) { const struct aspeed_gpio_bank *bank = to_bank(offset); const u32 mask = GPIO_BIT(offset); void __iomem *addr; u32 val; addr = bank_debounce_reg(gpio, bank, GPIO_DEBOUNCE_SEL1); val = ioread32(addr); iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE1(timer, offset), addr); addr = bank_debounce_reg(gpio, bank, GPIO_DEBOUNCE_SEL2); val = ioread32(addr); iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE2(timer, offset), addr); } static int enable_debounce(struct gpio_chip *chip, unsigned int offset, unsigned long usecs) { struct aspeed_gpio *gpio = gpiochip_get_data(chip); u32 requested_cycles; unsigned long flags; int rc; int i; if (!gpio->clk) return -EINVAL; rc = usecs_to_cycles(gpio, usecs, &requested_cycles); if (rc < 0) { dev_warn(chip->parent, "Failed to convert %luus to cycles at %luHz: %d\n", usecs, clk_get_rate(gpio->clk), rc); return rc; } spin_lock_irqsave(&gpio->lock, flags); if (timer_allocation_registered(gpio, offset)) { rc = unregister_allocated_timer(gpio, offset); if (rc < 0) goto out; } /* Try to find a timer already configured for the debounce period */ for (i = 1; i < ARRAY_SIZE(debounce_timers); i++) { u32 cycles; cycles = ioread32(gpio->base + debounce_timers[i]); if (requested_cycles == cycles) break; } if (i == ARRAY_SIZE(debounce_timers)) { int j; /* * As there are no timers configured for the requested debounce * period, find an unused timer instead */ for (j = 1; j < ARRAY_SIZE(gpio->timer_users); j++) { if (gpio->timer_users[j] == 0) break; } if (j == ARRAY_SIZE(gpio->timer_users)) { dev_warn(chip->parent, "Debounce timers exhausted, cannot debounce for period %luus\n", usecs); rc = -EPERM; /* * We already adjusted the accounting to remove @offset * as a user of its previous timer, so also configure * the hardware so @offset has timers disabled for * consistency. */ configure_timer(gpio, offset, 0); goto out; } i = j; iowrite32(requested_cycles, gpio->base + debounce_timers[i]); } if (WARN(i == 0, "Cannot register index of disabled timer\n")) { rc = -EINVAL; goto out; } register_allocated_timer(gpio, offset, i); configure_timer(gpio, offset, i); out: spin_unlock_irqrestore(&gpio->lock, flags); return rc; } static int disable_debounce(struct gpio_chip *chip, unsigned int offset) { struct aspeed_gpio *gpio = gpiochip_get_data(chip); unsigned long flags; int rc; spin_lock_irqsave(&gpio->lock, flags); rc = unregister_allocated_timer(gpio, offset); if (!rc) configure_timer(gpio, offset, 0); spin_unlock_irqrestore(&gpio->lock, flags); return rc; } static int set_debounce(struct gpio_chip *chip, unsigned int offset, unsigned long usecs) { struct aspeed_gpio *gpio = gpiochip_get_data(chip); if (!have_debounce(gpio, offset)) return -ENOTSUPP; if (usecs) return enable_debounce(chip, offset, usecs); return disable_debounce(chip, offset); } static int aspeed_gpio_set_config(struct gpio_chip *chip, unsigned int offset, unsigned long config) { unsigned long param = pinconf_to_config_param(config); u32 arg = pinconf_to_config_argument(config); if (param == PIN_CONFIG_INPUT_DEBOUNCE) return set_debounce(chip, offset, arg); else if (param == PIN_CONFIG_BIAS_DISABLE || param == PIN_CONFIG_BIAS_PULL_DOWN || param == PIN_CONFIG_DRIVE_STRENGTH) return pinctrl_gpio_set_config(offset, config); else if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN || param == PIN_CONFIG_DRIVE_OPEN_SOURCE) /* Return -ENOTSUPP to trigger emulation, as per datasheet */ return -ENOTSUPP; return -ENOTSUPP; } /* * Any banks not specified in a struct aspeed_bank_props array are assumed to * have the properties: * * { .input = 0xffffffff, .output = 0xffffffff } */ static const struct aspeed_bank_props ast2400_bank_props[] = { /* input output */ { 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */ { 6, 0x0000000f, 0x0fffff0f }, /* Y/Z/AA/AB, two 4-GPIO holes */ { }, }; static const struct aspeed_gpio_config ast2400_config = /* 220 for simplicity, really 216 with two 4-GPIO holes, four at end */ { .nr_gpios = 220, .props = ast2400_bank_props, }; static const struct aspeed_bank_props ast2500_bank_props[] = { /* input output */ { 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */ { 6, 0x0fffffff, 0x0fffffff }, /* Y/Z/AA/AB, 4-GPIO hole */ { 7, 0x000000ff, 0x000000ff }, /* AC */ { }, }; static const struct aspeed_gpio_config ast2500_config = /* 232 for simplicity, actual number is 228 (4-GPIO hole in GPIOAB) */ { .nr_gpios = 232, .props = ast2500_bank_props, }; static const struct of_device_id aspeed_gpio_of_table[] = { { .compatible = "aspeed,ast2400-gpio", .data = &ast2400_config, }, { .compatible = "aspeed,ast2500-gpio", .data = &ast2500_config, }, {} }; MODULE_DEVICE_TABLE(of, aspeed_gpio_of_table); static int __init aspeed_gpio_probe(struct platform_device *pdev) { const struct of_device_id *gpio_id; struct aspeed_gpio *gpio; struct resource *res; int rc; gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL); if (!gpio) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); gpio->base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(gpio->base)) return PTR_ERR(gpio->base); spin_lock_init(&gpio->lock); gpio_id = of_match_node(aspeed_gpio_of_table, pdev->dev.of_node); if (!gpio_id) return -EINVAL; gpio->clk = of_clk_get(pdev->dev.of_node, 0); if (IS_ERR(gpio->clk)) { dev_warn(&pdev->dev, "Failed to get clock from devicetree, debouncing disabled\n"); gpio->clk = NULL; } gpio->config = gpio_id->data; gpio->chip.parent = &pdev->dev; gpio->chip.ngpio = gpio->config->nr_gpios; gpio->chip.parent = &pdev->dev; gpio->chip.direction_input = aspeed_gpio_dir_in; gpio->chip.direction_output = aspeed_gpio_dir_out; gpio->chip.get_direction = aspeed_gpio_get_direction; gpio->chip.request = aspeed_gpio_request; gpio->chip.free = aspeed_gpio_free; gpio->chip.get = aspeed_gpio_get; gpio->chip.set = aspeed_gpio_set; gpio->chip.set_config = aspeed_gpio_set_config; gpio->chip.label = dev_name(&pdev->dev); gpio->chip.base = -1; gpio->chip.irq_need_valid_mask = true; rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio); if (rc < 0) return rc; gpio->offset_timer = devm_kzalloc(&pdev->dev, gpio->chip.ngpio, GFP_KERNEL); return aspeed_gpio_setup_irqs(gpio, pdev); } static struct platform_driver aspeed_gpio_driver = { .driver = { .name = KBUILD_MODNAME, .of_match_table = aspeed_gpio_of_table, }, }; module_platform_driver_probe(aspeed_gpio_driver, aspeed_gpio_probe); MODULE_DESCRIPTION("Aspeed GPIO Driver"); MODULE_LICENSE("GPL");