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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpio/gpio-ep93xx.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpio/gpio-ep93xx.c')
-rw-r--r-- | drivers/gpio/gpio-ep93xx.c | 461 |
1 files changed, 461 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-ep93xx.c b/drivers/gpio/gpio-ep93xx.c new file mode 100644 index 000000000..7edcdc575 --- /dev/null +++ b/drivers/gpio/gpio-ep93xx.c @@ -0,0 +1,461 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Generic EP93xx GPIO handling + * + * Copyright (c) 2008 Ryan Mallon + * Copyright (c) 2011 H Hartley Sweeten <hsweeten@visionengravers.com> + * + * Based on code originally from: + * linux/arch/arm/mach-ep93xx/core.c + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/slab.h> +#include <linux/gpio/driver.h> +#include <linux/bitops.h> + +#define EP93XX_GPIO_F_INT_STATUS 0x5c +#define EP93XX_GPIO_A_INT_STATUS 0xa0 +#define EP93XX_GPIO_B_INT_STATUS 0xbc + +/* Maximum value for gpio line identifiers */ +#define EP93XX_GPIO_LINE_MAX 63 + +/* Number of GPIO chips in EP93XX */ +#define EP93XX_GPIO_CHIP_NUM 8 + +/* Maximum value for irq capable line identifiers */ +#define EP93XX_GPIO_LINE_MAX_IRQ 23 + +#define EP93XX_GPIO_A_IRQ_BASE 64 +#define EP93XX_GPIO_B_IRQ_BASE 72 +/* + * Static mapping of GPIO bank F IRQS: + * F0..F7 (16..24) to irq 80..87. + */ +#define EP93XX_GPIO_F_IRQ_BASE 80 + +struct ep93xx_gpio_irq_chip { + struct irq_chip ic; + u8 irq_offset; + u8 int_unmasked; + u8 int_enabled; + u8 int_type1; + u8 int_type2; + u8 int_debounce; +}; + +struct ep93xx_gpio_chip { + struct gpio_chip gc; + struct ep93xx_gpio_irq_chip *eic; +}; + +struct ep93xx_gpio { + void __iomem *base; + struct ep93xx_gpio_chip gc[EP93XX_GPIO_CHIP_NUM]; +}; + +#define to_ep93xx_gpio_chip(x) container_of(x, struct ep93xx_gpio_chip, gc) + +static struct ep93xx_gpio_irq_chip *to_ep93xx_gpio_irq_chip(struct gpio_chip *gc) +{ + struct ep93xx_gpio_chip *egc = to_ep93xx_gpio_chip(gc); + + return egc->eic; +} + +/************************************************************************* + * Interrupt handling for EP93xx on-chip GPIOs + *************************************************************************/ +#define EP93XX_INT_TYPE1_OFFSET 0x00 +#define EP93XX_INT_TYPE2_OFFSET 0x04 +#define EP93XX_INT_EOI_OFFSET 0x08 +#define EP93XX_INT_EN_OFFSET 0x0c +#define EP93XX_INT_STATUS_OFFSET 0x10 +#define EP93XX_INT_RAW_STATUS_OFFSET 0x14 +#define EP93XX_INT_DEBOUNCE_OFFSET 0x18 + +static void ep93xx_gpio_update_int_params(struct ep93xx_gpio *epg, + struct ep93xx_gpio_irq_chip *eic) +{ + writeb_relaxed(0, epg->base + eic->irq_offset + EP93XX_INT_EN_OFFSET); + + writeb_relaxed(eic->int_type2, + epg->base + eic->irq_offset + EP93XX_INT_TYPE2_OFFSET); + + writeb_relaxed(eic->int_type1, + epg->base + eic->irq_offset + EP93XX_INT_TYPE1_OFFSET); + + writeb_relaxed(eic->int_unmasked & eic->int_enabled, + epg->base + eic->irq_offset + EP93XX_INT_EN_OFFSET); +} + +static void ep93xx_gpio_int_debounce(struct gpio_chip *gc, + unsigned int offset, bool enable) +{ + struct ep93xx_gpio *epg = gpiochip_get_data(gc); + struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc); + int port_mask = BIT(offset); + + if (enable) + eic->int_debounce |= port_mask; + else + eic->int_debounce &= ~port_mask; + + writeb(eic->int_debounce, + epg->base + eic->irq_offset + EP93XX_INT_DEBOUNCE_OFFSET); +} + +static void ep93xx_gpio_ab_irq_handler(struct irq_desc *desc) +{ + struct gpio_chip *gc = irq_desc_get_handler_data(desc); + struct ep93xx_gpio *epg = gpiochip_get_data(gc); + struct irq_chip *irqchip = irq_desc_get_chip(desc); + unsigned long stat; + int offset; + + chained_irq_enter(irqchip, desc); + + /* + * Dispatch the IRQs to the irqdomain of each A and B + * gpiochip irqdomains depending on what has fired. + * The tricky part is that the IRQ line is shared + * between bank A and B and each has their own gpiochip. + */ + stat = readb(epg->base + EP93XX_GPIO_A_INT_STATUS); + for_each_set_bit(offset, &stat, 8) + generic_handle_domain_irq(epg->gc[0].gc.irq.domain, + offset); + + stat = readb(epg->base + EP93XX_GPIO_B_INT_STATUS); + for_each_set_bit(offset, &stat, 8) + generic_handle_domain_irq(epg->gc[1].gc.irq.domain, + offset); + + chained_irq_exit(irqchip, desc); +} + +static void ep93xx_gpio_f_irq_handler(struct irq_desc *desc) +{ + /* + * map discontiguous hw irq range to continuous sw irq range: + * + * IRQ_EP93XX_GPIO{0..7}MUX -> EP93XX_GPIO_LINE_F{0..7} + */ + struct irq_chip *irqchip = irq_desc_get_chip(desc); + unsigned int irq = irq_desc_get_irq(desc); + int port_f_idx = (irq & 7) ^ 4; /* {20..23,48..51} -> {0..7} */ + int gpio_irq = EP93XX_GPIO_F_IRQ_BASE + port_f_idx; + + chained_irq_enter(irqchip, desc); + generic_handle_irq(gpio_irq); + chained_irq_exit(irqchip, desc); +} + +static void ep93xx_gpio_irq_ack(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc); + struct ep93xx_gpio *epg = gpiochip_get_data(gc); + int port_mask = BIT(d->irq & 7); + + if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH) { + eic->int_type2 ^= port_mask; /* switch edge direction */ + ep93xx_gpio_update_int_params(epg, eic); + } + + writeb(port_mask, epg->base + eic->irq_offset + EP93XX_INT_EOI_OFFSET); +} + +static void ep93xx_gpio_irq_mask_ack(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc); + struct ep93xx_gpio *epg = gpiochip_get_data(gc); + int port_mask = BIT(d->irq & 7); + + if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH) + eic->int_type2 ^= port_mask; /* switch edge direction */ + + eic->int_unmasked &= ~port_mask; + ep93xx_gpio_update_int_params(epg, eic); + + writeb(port_mask, epg->base + eic->irq_offset + EP93XX_INT_EOI_OFFSET); +} + +static void ep93xx_gpio_irq_mask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc); + struct ep93xx_gpio *epg = gpiochip_get_data(gc); + + eic->int_unmasked &= ~BIT(d->irq & 7); + ep93xx_gpio_update_int_params(epg, eic); +} + +static void ep93xx_gpio_irq_unmask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc); + struct ep93xx_gpio *epg = gpiochip_get_data(gc); + + eic->int_unmasked |= BIT(d->irq & 7); + ep93xx_gpio_update_int_params(epg, eic); +} + +/* + * gpio_int_type1 controls whether the interrupt is level (0) or + * edge (1) triggered, while gpio_int_type2 controls whether it + * triggers on low/falling (0) or high/rising (1). + */ +static int ep93xx_gpio_irq_type(struct irq_data *d, unsigned int type) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc); + struct ep93xx_gpio *epg = gpiochip_get_data(gc); + int offset = d->irq & 7; + int port_mask = BIT(offset); + irq_flow_handler_t handler; + + gc->direction_input(gc, offset); + + switch (type) { + case IRQ_TYPE_EDGE_RISING: + eic->int_type1 |= port_mask; + eic->int_type2 |= port_mask; + handler = handle_edge_irq; + break; + case IRQ_TYPE_EDGE_FALLING: + eic->int_type1 |= port_mask; + eic->int_type2 &= ~port_mask; + handler = handle_edge_irq; + break; + case IRQ_TYPE_LEVEL_HIGH: + eic->int_type1 &= ~port_mask; + eic->int_type2 |= port_mask; + handler = handle_level_irq; + break; + case IRQ_TYPE_LEVEL_LOW: + eic->int_type1 &= ~port_mask; + eic->int_type2 &= ~port_mask; + handler = handle_level_irq; + break; + case IRQ_TYPE_EDGE_BOTH: + eic->int_type1 |= port_mask; + /* set initial polarity based on current input level */ + if (gc->get(gc, offset)) + eic->int_type2 &= ~port_mask; /* falling */ + else + eic->int_type2 |= port_mask; /* rising */ + handler = handle_edge_irq; + break; + default: + return -EINVAL; + } + + irq_set_handler_locked(d, handler); + + eic->int_enabled |= port_mask; + + ep93xx_gpio_update_int_params(epg, eic); + + return 0; +} + +/************************************************************************* + * gpiolib interface for EP93xx on-chip GPIOs + *************************************************************************/ +struct ep93xx_gpio_bank { + const char *label; + int data; + int dir; + int irq; + int base; + bool has_irq; + bool has_hierarchical_irq; + unsigned int irq_base; +}; + +#define EP93XX_GPIO_BANK(_label, _data, _dir, _irq, _base, _has_irq, _has_hier, _irq_base) \ + { \ + .label = _label, \ + .data = _data, \ + .dir = _dir, \ + .irq = _irq, \ + .base = _base, \ + .has_irq = _has_irq, \ + .has_hierarchical_irq = _has_hier, \ + .irq_base = _irq_base, \ + } + +static struct ep93xx_gpio_bank ep93xx_gpio_banks[] = { + /* Bank A has 8 IRQs */ + EP93XX_GPIO_BANK("A", 0x00, 0x10, 0x90, 0, true, false, EP93XX_GPIO_A_IRQ_BASE), + /* Bank B has 8 IRQs */ + EP93XX_GPIO_BANK("B", 0x04, 0x14, 0xac, 8, true, false, EP93XX_GPIO_B_IRQ_BASE), + EP93XX_GPIO_BANK("C", 0x08, 0x18, 0x00, 40, false, false, 0), + EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 0x00, 24, false, false, 0), + EP93XX_GPIO_BANK("E", 0x20, 0x24, 0x00, 32, false, false, 0), + /* Bank F has 8 IRQs */ + EP93XX_GPIO_BANK("F", 0x30, 0x34, 0x4c, 16, false, true, EP93XX_GPIO_F_IRQ_BASE), + EP93XX_GPIO_BANK("G", 0x38, 0x3c, 0x00, 48, false, false, 0), + EP93XX_GPIO_BANK("H", 0x40, 0x44, 0x00, 56, false, false, 0), +}; + +static int ep93xx_gpio_set_config(struct gpio_chip *gc, unsigned offset, + unsigned long config) +{ + u32 debounce; + + if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE) + return -ENOTSUPP; + + debounce = pinconf_to_config_argument(config); + ep93xx_gpio_int_debounce(gc, offset, debounce ? true : false); + + return 0; +} + +static void ep93xx_init_irq_chip(struct device *dev, struct irq_chip *ic) +{ + ic->irq_ack = ep93xx_gpio_irq_ack; + ic->irq_mask_ack = ep93xx_gpio_irq_mask_ack; + ic->irq_mask = ep93xx_gpio_irq_mask; + ic->irq_unmask = ep93xx_gpio_irq_unmask; + ic->irq_set_type = ep93xx_gpio_irq_type; +} + +static int ep93xx_gpio_add_bank(struct ep93xx_gpio_chip *egc, + struct platform_device *pdev, + struct ep93xx_gpio *epg, + struct ep93xx_gpio_bank *bank) +{ + void __iomem *data = epg->base + bank->data; + void __iomem *dir = epg->base + bank->dir; + struct gpio_chip *gc = &egc->gc; + struct device *dev = &pdev->dev; + struct gpio_irq_chip *girq; + int err; + + err = bgpio_init(gc, dev, 1, data, NULL, NULL, dir, NULL, 0); + if (err) + return err; + + gc->label = bank->label; + gc->base = bank->base; + + girq = &gc->irq; + if (bank->has_irq || bank->has_hierarchical_irq) { + struct irq_chip *ic; + + gc->set_config = ep93xx_gpio_set_config; + egc->eic = devm_kcalloc(dev, 1, + sizeof(*egc->eic), + GFP_KERNEL); + if (!egc->eic) + return -ENOMEM; + egc->eic->irq_offset = bank->irq; + ic = &egc->eic->ic; + ic->name = devm_kasprintf(dev, GFP_KERNEL, "gpio-irq-%s", bank->label); + if (!ic->name) + return -ENOMEM; + ep93xx_init_irq_chip(dev, ic); + girq->chip = ic; + } + + if (bank->has_irq) { + int ab_parent_irq = platform_get_irq(pdev, 0); + + girq->parent_handler = ep93xx_gpio_ab_irq_handler; + girq->num_parents = 1; + girq->parents = devm_kcalloc(dev, girq->num_parents, + sizeof(*girq->parents), + GFP_KERNEL); + if (!girq->parents) + return -ENOMEM; + girq->default_type = IRQ_TYPE_NONE; + girq->handler = handle_level_irq; + girq->parents[0] = ab_parent_irq; + girq->first = bank->irq_base; + } + + /* Only bank F has especially funky IRQ handling */ + if (bank->has_hierarchical_irq) { + int gpio_irq; + int i; + + /* + * FIXME: convert this to use hierarchical IRQ support! + * this requires fixing the root irqchip to be hierarchical. + */ + girq->parent_handler = ep93xx_gpio_f_irq_handler; + girq->num_parents = 8; + girq->parents = devm_kcalloc(dev, girq->num_parents, + sizeof(*girq->parents), + GFP_KERNEL); + if (!girq->parents) + return -ENOMEM; + /* Pick resources 1..8 for these IRQs */ + for (i = 0; i < girq->num_parents; i++) { + girq->parents[i] = platform_get_irq(pdev, i + 1); + gpio_irq = bank->irq_base + i; + irq_set_chip_data(gpio_irq, &epg->gc[5]); + irq_set_chip_and_handler(gpio_irq, + girq->chip, + handle_level_irq); + irq_clear_status_flags(gpio_irq, IRQ_NOREQUEST); + } + girq->default_type = IRQ_TYPE_NONE; + girq->handler = handle_level_irq; + girq->first = bank->irq_base; + } + + return devm_gpiochip_add_data(dev, gc, epg); +} + +static int ep93xx_gpio_probe(struct platform_device *pdev) +{ + struct ep93xx_gpio *epg; + int i; + + epg = devm_kzalloc(&pdev->dev, sizeof(*epg), GFP_KERNEL); + if (!epg) + return -ENOMEM; + + epg->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(epg->base)) + return PTR_ERR(epg->base); + + for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) { + struct ep93xx_gpio_chip *gc = &epg->gc[i]; + struct ep93xx_gpio_bank *bank = &ep93xx_gpio_banks[i]; + + if (ep93xx_gpio_add_bank(gc, pdev, epg, bank)) + dev_warn(&pdev->dev, "Unable to add gpio bank %s\n", + bank->label); + } + + return 0; +} + +static struct platform_driver ep93xx_gpio_driver = { + .driver = { + .name = "gpio-ep93xx", + }, + .probe = ep93xx_gpio_probe, +}; + +static int __init ep93xx_gpio_init(void) +{ + return platform_driver_register(&ep93xx_gpio_driver); +} +postcore_initcall(ep93xx_gpio_init); + +MODULE_AUTHOR("Ryan Mallon <ryan@bluewatersys.com> " + "H Hartley Sweeten <hsweeten@visionengravers.com>"); +MODULE_DESCRIPTION("EP93XX GPIO driver"); +MODULE_LICENSE("GPL"); |