diff options
Diffstat (limited to 'drivers/gpio/gpio-dwapb.c')
| -rw-r--r-- | drivers/gpio/gpio-dwapb.c | 692 |
1 files changed, 692 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c new file mode 100644 index 000000000..58faf04fc --- /dev/null +++ b/drivers/gpio/gpio-dwapb.c @@ -0,0 +1,692 @@ +/* + * Copyright (c) 2011 Jamie Iles + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * All enquiries to support@picochip.com + */ +#include <linux/basic_mmio_gpio.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/platform_data/gpio-dwapb.h> +#include <linux/slab.h> + +#define GPIO_SWPORTA_DR 0x00 +#define GPIO_SWPORTA_DDR 0x04 +#define GPIO_SWPORTB_DR 0x0c +#define GPIO_SWPORTB_DDR 0x10 +#define GPIO_SWPORTC_DR 0x18 +#define GPIO_SWPORTC_DDR 0x1c +#define GPIO_SWPORTD_DR 0x24 +#define GPIO_SWPORTD_DDR 0x28 +#define GPIO_INTEN 0x30 +#define GPIO_INTMASK 0x34 +#define GPIO_INTTYPE_LEVEL 0x38 +#define GPIO_INT_POLARITY 0x3c +#define GPIO_INTSTATUS 0x40 +#define GPIO_PORTA_DEBOUNCE 0x48 +#define GPIO_PORTA_EOI 0x4c +#define GPIO_EXT_PORTA 0x50 +#define GPIO_EXT_PORTB 0x54 +#define GPIO_EXT_PORTC 0x58 +#define GPIO_EXT_PORTD 0x5c + +#define DWAPB_MAX_PORTS 4 +#define GPIO_EXT_PORT_SIZE (GPIO_EXT_PORTB - GPIO_EXT_PORTA) +#define GPIO_SWPORT_DR_SIZE (GPIO_SWPORTB_DR - GPIO_SWPORTA_DR) +#define GPIO_SWPORT_DDR_SIZE (GPIO_SWPORTB_DDR - GPIO_SWPORTA_DDR) + +struct dwapb_gpio; + +#ifdef CONFIG_PM_SLEEP +/* Store GPIO context across system-wide suspend/resume transitions */ +struct dwapb_context { + u32 data; + u32 dir; + u32 ext; + u32 int_en; + u32 int_mask; + u32 int_type; + u32 int_pol; + u32 int_deb; +}; +#endif + +struct dwapb_gpio_port { + struct bgpio_chip bgc; + bool is_registered; + struct dwapb_gpio *gpio; +#ifdef CONFIG_PM_SLEEP + struct dwapb_context *ctx; +#endif + unsigned int idx; +}; + +struct dwapb_gpio { + struct device *dev; + void __iomem *regs; + struct dwapb_gpio_port *ports; + unsigned int nr_ports; + struct irq_domain *domain; +}; + +static inline struct dwapb_gpio_port * +to_dwapb_gpio_port(struct bgpio_chip *bgc) +{ + return container_of(bgc, struct dwapb_gpio_port, bgc); +} + +static inline u32 dwapb_read(struct dwapb_gpio *gpio, unsigned int offset) +{ + struct bgpio_chip *bgc = &gpio->ports[0].bgc; + void __iomem *reg_base = gpio->regs; + + return bgc->read_reg(reg_base + offset); +} + +static inline void dwapb_write(struct dwapb_gpio *gpio, unsigned int offset, + u32 val) +{ + struct bgpio_chip *bgc = &gpio->ports[0].bgc; + void __iomem *reg_base = gpio->regs; + + bgc->write_reg(reg_base + offset, val); +} + +static int dwapb_gpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + struct dwapb_gpio_port *port = to_dwapb_gpio_port(bgc); + struct dwapb_gpio *gpio = port->gpio; + + return irq_find_mapping(gpio->domain, offset); +} + +static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs) +{ + u32 v = dwapb_read(gpio, GPIO_INT_POLARITY); + + if (gpio_get_value(gpio->ports[0].bgc.gc.base + offs)) + v &= ~BIT(offs); + else + v |= BIT(offs); + + dwapb_write(gpio, GPIO_INT_POLARITY, v); +} + +static u32 dwapb_do_irq(struct dwapb_gpio *gpio) +{ + u32 irq_status = readl_relaxed(gpio->regs + GPIO_INTSTATUS); + u32 ret = irq_status; + + while (irq_status) { + int hwirq = fls(irq_status) - 1; + int gpio_irq = irq_find_mapping(gpio->domain, hwirq); + + generic_handle_irq(gpio_irq); + irq_status &= ~BIT(hwirq); + + if ((irq_get_trigger_type(gpio_irq) & IRQ_TYPE_SENSE_MASK) + == IRQ_TYPE_EDGE_BOTH) + dwapb_toggle_trigger(gpio, hwirq); + } + + return ret; +} + +static void dwapb_irq_handler(u32 irq, struct irq_desc *desc) +{ + struct dwapb_gpio *gpio = irq_get_handler_data(irq); + struct irq_chip *chip = irq_desc_get_chip(desc); + + dwapb_do_irq(gpio); + + if (chip->irq_eoi) + chip->irq_eoi(irq_desc_get_irq_data(desc)); +} + +static void dwapb_irq_enable(struct irq_data *d) +{ + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d); + struct dwapb_gpio *gpio = igc->private; + struct bgpio_chip *bgc = &gpio->ports[0].bgc; + unsigned long flags; + u32 val; + + spin_lock_irqsave(&bgc->lock, flags); + val = dwapb_read(gpio, GPIO_INTEN); + val |= BIT(d->hwirq); + dwapb_write(gpio, GPIO_INTEN, val); + spin_unlock_irqrestore(&bgc->lock, flags); +} + +static void dwapb_irq_disable(struct irq_data *d) +{ + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d); + struct dwapb_gpio *gpio = igc->private; + struct bgpio_chip *bgc = &gpio->ports[0].bgc; + unsigned long flags; + u32 val; + + spin_lock_irqsave(&bgc->lock, flags); + val = dwapb_read(gpio, GPIO_INTEN); + val &= ~BIT(d->hwirq); + dwapb_write(gpio, GPIO_INTEN, val); + spin_unlock_irqrestore(&bgc->lock, flags); +} + +static int dwapb_irq_reqres(struct irq_data *d) +{ + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d); + struct dwapb_gpio *gpio = igc->private; + struct bgpio_chip *bgc = &gpio->ports[0].bgc; + + if (gpiochip_lock_as_irq(&bgc->gc, irqd_to_hwirq(d))) { + dev_err(gpio->dev, "unable to lock HW IRQ %lu for IRQ\n", + irqd_to_hwirq(d)); + return -EINVAL; + } + return 0; +} + +static void dwapb_irq_relres(struct irq_data *d) +{ + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d); + struct dwapb_gpio *gpio = igc->private; + struct bgpio_chip *bgc = &gpio->ports[0].bgc; + + gpiochip_unlock_as_irq(&bgc->gc, irqd_to_hwirq(d)); +} + +static int dwapb_irq_set_type(struct irq_data *d, u32 type) +{ + struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d); + struct dwapb_gpio *gpio = igc->private; + struct bgpio_chip *bgc = &gpio->ports[0].bgc; + int bit = d->hwirq; + unsigned long level, polarity, flags; + + if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING | + IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) + return -EINVAL; + + spin_lock_irqsave(&bgc->lock, flags); + level = dwapb_read(gpio, GPIO_INTTYPE_LEVEL); + polarity = dwapb_read(gpio, GPIO_INT_POLARITY); + + switch (type) { + case IRQ_TYPE_EDGE_BOTH: + level |= BIT(bit); + dwapb_toggle_trigger(gpio, bit); + break; + case IRQ_TYPE_EDGE_RISING: + level |= BIT(bit); + polarity |= BIT(bit); + break; + case IRQ_TYPE_EDGE_FALLING: + level |= BIT(bit); + polarity &= ~BIT(bit); + break; + case IRQ_TYPE_LEVEL_HIGH: + level &= ~BIT(bit); + polarity |= BIT(bit); + break; + case IRQ_TYPE_LEVEL_LOW: + level &= ~BIT(bit); + polarity &= ~BIT(bit); + break; + } + + irq_setup_alt_chip(d, type); + + dwapb_write(gpio, GPIO_INTTYPE_LEVEL, level); + dwapb_write(gpio, GPIO_INT_POLARITY, polarity); + spin_unlock_irqrestore(&bgc->lock, flags); + + return 0; +} + +static int dwapb_gpio_set_debounce(struct gpio_chip *gc, + unsigned offset, unsigned debounce) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + struct dwapb_gpio_port *port = to_dwapb_gpio_port(bgc); + struct dwapb_gpio *gpio = port->gpio; + unsigned long flags, val_deb; + unsigned long mask = bgc->pin2mask(bgc, offset); + + spin_lock_irqsave(&bgc->lock, flags); + + val_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE); + if (debounce) + dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb | mask); + else + dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, val_deb & ~mask); + + spin_unlock_irqrestore(&bgc->lock, flags); + + return 0; +} + +static irqreturn_t dwapb_irq_handler_mfd(int irq, void *dev_id) +{ + u32 worked; + struct dwapb_gpio *gpio = dev_id; + + worked = dwapb_do_irq(gpio); + + return worked ? IRQ_HANDLED : IRQ_NONE; +} + +static void dwapb_configure_irqs(struct dwapb_gpio *gpio, + struct dwapb_gpio_port *port, + struct dwapb_port_property *pp) +{ + struct gpio_chip *gc = &port->bgc.gc; + struct device_node *node = pp->node; + struct irq_chip_generic *irq_gc = NULL; + unsigned int hwirq, ngpio = gc->ngpio; + struct irq_chip_type *ct; + int err, i; + + gpio->domain = irq_domain_add_linear(node, ngpio, + &irq_generic_chip_ops, gpio); + if (!gpio->domain) + return; + + err = irq_alloc_domain_generic_chips(gpio->domain, ngpio, 2, + "gpio-dwapb", handle_level_irq, + IRQ_NOREQUEST, 0, + IRQ_GC_INIT_NESTED_LOCK); + if (err) { + dev_info(gpio->dev, "irq_alloc_domain_generic_chips failed\n"); + irq_domain_remove(gpio->domain); + gpio->domain = NULL; + return; + } + + irq_gc = irq_get_domain_generic_chip(gpio->domain, 0); + if (!irq_gc) { + irq_domain_remove(gpio->domain); + gpio->domain = NULL; + return; + } + + irq_gc->reg_base = gpio->regs; + irq_gc->private = gpio; + + for (i = 0; i < 2; i++) { + ct = &irq_gc->chip_types[i]; + ct->chip.irq_ack = irq_gc_ack_set_bit; + ct->chip.irq_mask = irq_gc_mask_set_bit; + ct->chip.irq_unmask = irq_gc_mask_clr_bit; + ct->chip.irq_set_type = dwapb_irq_set_type; + ct->chip.irq_enable = dwapb_irq_enable; + ct->chip.irq_disable = dwapb_irq_disable; + ct->chip.irq_request_resources = dwapb_irq_reqres; + ct->chip.irq_release_resources = dwapb_irq_relres; + ct->regs.ack = GPIO_PORTA_EOI; + ct->regs.mask = GPIO_INTMASK; + ct->type = IRQ_TYPE_LEVEL_MASK; + } + + irq_gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK; + irq_gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH; + irq_gc->chip_types[1].handler = handle_edge_irq; + + if (!pp->irq_shared) { + irq_set_chained_handler(pp->irq, dwapb_irq_handler); + irq_set_handler_data(pp->irq, gpio); + } else { + /* + * Request a shared IRQ since where MFD would have devices + * using the same irq pin + */ + err = devm_request_irq(gpio->dev, pp->irq, + dwapb_irq_handler_mfd, + IRQF_SHARED, "gpio-dwapb-mfd", gpio); + if (err) { + dev_err(gpio->dev, "error requesting IRQ\n"); + irq_domain_remove(gpio->domain); + gpio->domain = NULL; + return; + } + } + + for (hwirq = 0 ; hwirq < ngpio ; hwirq++) + irq_create_mapping(gpio->domain, hwirq); + + port->bgc.gc.to_irq = dwapb_gpio_to_irq; +} + +static void dwapb_irq_teardown(struct dwapb_gpio *gpio) +{ + struct dwapb_gpio_port *port = &gpio->ports[0]; + struct gpio_chip *gc = &port->bgc.gc; + unsigned int ngpio = gc->ngpio; + irq_hw_number_t hwirq; + + if (!gpio->domain) + return; + + for (hwirq = 0 ; hwirq < ngpio ; hwirq++) + irq_dispose_mapping(irq_find_mapping(gpio->domain, hwirq)); + + irq_domain_remove(gpio->domain); + gpio->domain = NULL; +} + +static int dwapb_gpio_add_port(struct dwapb_gpio *gpio, + struct dwapb_port_property *pp, + unsigned int offs) +{ + struct dwapb_gpio_port *port; + void __iomem *dat, *set, *dirout; + int err; + + port = &gpio->ports[offs]; + port->gpio = gpio; + port->idx = pp->idx; + +#ifdef CONFIG_PM_SLEEP + port->ctx = devm_kzalloc(gpio->dev, sizeof(*port->ctx), GFP_KERNEL); + if (!port->ctx) + return -ENOMEM; +#endif + + dat = gpio->regs + GPIO_EXT_PORTA + (pp->idx * GPIO_EXT_PORT_SIZE); + set = gpio->regs + GPIO_SWPORTA_DR + (pp->idx * GPIO_SWPORT_DR_SIZE); + dirout = gpio->regs + GPIO_SWPORTA_DDR + + (pp->idx * GPIO_SWPORT_DDR_SIZE); + + err = bgpio_init(&port->bgc, gpio->dev, 4, dat, set, NULL, dirout, + NULL, false); + if (err) { + dev_err(gpio->dev, "failed to init gpio chip for %s\n", + pp->name); + return err; + } + +#ifdef CONFIG_OF_GPIO + port->bgc.gc.of_node = pp->node; +#endif + port->bgc.gc.ngpio = pp->ngpio; + port->bgc.gc.base = pp->gpio_base; + + /* Only port A support debounce */ + if (pp->idx == 0) + port->bgc.gc.set_debounce = dwapb_gpio_set_debounce; + + if (pp->irq) + dwapb_configure_irqs(gpio, port, pp); + + err = gpiochip_add(&port->bgc.gc); + if (err) + dev_err(gpio->dev, "failed to register gpiochip for %s\n", + pp->name); + else + port->is_registered = true; + + return err; +} + +static void dwapb_gpio_unregister(struct dwapb_gpio *gpio) +{ + unsigned int m; + + for (m = 0; m < gpio->nr_ports; ++m) + if (gpio->ports[m].is_registered) + gpiochip_remove(&gpio->ports[m].bgc.gc); +} + +static struct dwapb_platform_data * +dwapb_gpio_get_pdata_of(struct device *dev) +{ + struct device_node *node, *port_np; + struct dwapb_platform_data *pdata; + struct dwapb_port_property *pp; + int nports; + int i; + + node = dev->of_node; + if (!IS_ENABLED(CONFIG_OF_GPIO) || !node) + return ERR_PTR(-ENODEV); + + nports = of_get_child_count(node); + if (nports == 0) + return ERR_PTR(-ENODEV); + + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return ERR_PTR(-ENOMEM); + + pdata->properties = devm_kcalloc(dev, nports, sizeof(*pp), GFP_KERNEL); + if (!pdata->properties) + return ERR_PTR(-ENOMEM); + + pdata->nports = nports; + + i = 0; + for_each_child_of_node(node, port_np) { + pp = &pdata->properties[i++]; + pp->node = port_np; + + if (of_property_read_u32(port_np, "reg", &pp->idx) || + pp->idx >= DWAPB_MAX_PORTS) { + dev_err(dev, "missing/invalid port index for %s\n", + port_np->full_name); + return ERR_PTR(-EINVAL); + } + + if (of_property_read_u32(port_np, "snps,nr-gpios", + &pp->ngpio)) { + dev_info(dev, "failed to get number of gpios for %s\n", + port_np->full_name); + pp->ngpio = 32; + } + + /* + * Only port A can provide interrupts in all configurations of + * the IP. + */ + if (pp->idx == 0 && + of_property_read_bool(port_np, "interrupt-controller")) { + pp->irq = irq_of_parse_and_map(port_np, 0); + if (!pp->irq) { + dev_warn(dev, "no irq for bank %s\n", + port_np->full_name); + } + } + + pp->irq_shared = false; + pp->gpio_base = -1; + pp->name = port_np->full_name; + } + + return pdata; +} + +static int dwapb_gpio_probe(struct platform_device *pdev) +{ + unsigned int i; + struct resource *res; + struct dwapb_gpio *gpio; + int err; + struct device *dev = &pdev->dev; + struct dwapb_platform_data *pdata = dev_get_platdata(dev); + + if (!pdata) { + pdata = dwapb_gpio_get_pdata_of(dev); + if (IS_ERR(pdata)) + return PTR_ERR(pdata); + } + + if (!pdata->nports) + return -ENODEV; + + gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL); + if (!gpio) + return -ENOMEM; + + gpio->dev = &pdev->dev; + gpio->nr_ports = pdata->nports; + + gpio->ports = devm_kcalloc(&pdev->dev, gpio->nr_ports, + sizeof(*gpio->ports), GFP_KERNEL); + if (!gpio->ports) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + gpio->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(gpio->regs)) + return PTR_ERR(gpio->regs); + + for (i = 0; i < gpio->nr_ports; i++) { + err = dwapb_gpio_add_port(gpio, &pdata->properties[i], i); + if (err) + goto out_unregister; + } + platform_set_drvdata(pdev, gpio); + + return 0; + +out_unregister: + dwapb_gpio_unregister(gpio); + dwapb_irq_teardown(gpio); + + return err; +} + +static int dwapb_gpio_remove(struct platform_device *pdev) +{ + struct dwapb_gpio *gpio = platform_get_drvdata(pdev); + + dwapb_gpio_unregister(gpio); + dwapb_irq_teardown(gpio); + + return 0; +} + +static const struct of_device_id dwapb_of_match[] = { + { .compatible = "snps,dw-apb-gpio" }, + { /* Sentinel */ } +}; +MODULE_DEVICE_TABLE(of, dwapb_of_match); + +#ifdef CONFIG_PM_SLEEP +static int dwapb_gpio_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct dwapb_gpio *gpio = platform_get_drvdata(pdev); + struct bgpio_chip *bgc = &gpio->ports[0].bgc; + unsigned long flags; + int i; + + spin_lock_irqsave(&bgc->lock, flags); + for (i = 0; i < gpio->nr_ports; i++) { + unsigned int offset; + unsigned int idx = gpio->ports[i].idx; + struct dwapb_context *ctx = gpio->ports[i].ctx; + + BUG_ON(!ctx); + + offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_SIZE; + ctx->dir = dwapb_read(gpio, offset); + + offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_SIZE; + ctx->data = dwapb_read(gpio, offset); + + offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_SIZE; + ctx->ext = dwapb_read(gpio, offset); + + /* Only port A can provide interrupts */ + if (idx == 0) { + ctx->int_mask = dwapb_read(gpio, GPIO_INTMASK); + ctx->int_en = dwapb_read(gpio, GPIO_INTEN); + ctx->int_pol = dwapb_read(gpio, GPIO_INT_POLARITY); + ctx->int_type = dwapb_read(gpio, GPIO_INTTYPE_LEVEL); + ctx->int_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE); + + /* Mask out interrupts */ + dwapb_write(gpio, GPIO_INTMASK, 0xffffffff); + } + } + spin_unlock_irqrestore(&bgc->lock, flags); + + return 0; +} + +static int dwapb_gpio_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct dwapb_gpio *gpio = platform_get_drvdata(pdev); + struct bgpio_chip *bgc = &gpio->ports[0].bgc; + unsigned long flags; + int i; + + spin_lock_irqsave(&bgc->lock, flags); + for (i = 0; i < gpio->nr_ports; i++) { + unsigned int offset; + unsigned int idx = gpio->ports[i].idx; + struct dwapb_context *ctx = gpio->ports[i].ctx; + + BUG_ON(!ctx); + + offset = GPIO_SWPORTA_DR + idx * GPIO_SWPORT_DR_SIZE; + dwapb_write(gpio, offset, ctx->data); + + offset = GPIO_SWPORTA_DDR + idx * GPIO_SWPORT_DDR_SIZE; + dwapb_write(gpio, offset, ctx->dir); + + offset = GPIO_EXT_PORTA + idx * GPIO_EXT_PORT_SIZE; + dwapb_write(gpio, offset, ctx->ext); + + /* Only port A can provide interrupts */ + if (idx == 0) { + dwapb_write(gpio, GPIO_INTTYPE_LEVEL, ctx->int_type); + dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol); + dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, ctx->int_deb); + dwapb_write(gpio, GPIO_INTEN, ctx->int_en); + dwapb_write(gpio, GPIO_INTMASK, ctx->int_mask); + + /* Clear out spurious interrupts */ + dwapb_write(gpio, GPIO_PORTA_EOI, 0xffffffff); + } + } + spin_unlock_irqrestore(&bgc->lock, flags); + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(dwapb_gpio_pm_ops, dwapb_gpio_suspend, + dwapb_gpio_resume); + +static struct platform_driver dwapb_gpio_driver = { + .driver = { + .name = "gpio-dwapb", + .pm = &dwapb_gpio_pm_ops, + .of_match_table = of_match_ptr(dwapb_of_match), + }, + .probe = dwapb_gpio_probe, + .remove = dwapb_gpio_remove, +}; + +module_platform_driver(dwapb_gpio_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jamie Iles"); +MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver"); |