diff options
Diffstat (limited to 'drivers/gpio/gpio-xgene-sb.c')
-rw-r--r-- | drivers/gpio/gpio-xgene-sb.c | 354 |
1 files changed, 354 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-xgene-sb.c b/drivers/gpio/gpio-xgene-sb.c new file mode 100644 index 000000000..2eb76f35a --- /dev/null +++ b/drivers/gpio/gpio-xgene-sb.c @@ -0,0 +1,354 @@ +/* + * AppliedMicro X-Gene SoC GPIO-Standby Driver + * + * Copyright (c) 2014, Applied Micro Circuits Corporation + * Author: Tin Huynh <tnhuynh@apm.com>. + * Y Vo <yvo@apm.com>. + * Quan Nguyen <qnguyen@apm.com>. + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/module.h> +#include <linux/io.h> +#include <linux/platform_device.h> +#include <linux/of_gpio.h> +#include <linux/gpio/driver.h> +#include <linux/acpi.h> + +#include "gpiolib.h" + +/* Common property names */ +#define XGENE_NIRQ_PROPERTY "apm,nr-irqs" +#define XGENE_NGPIO_PROPERTY "apm,nr-gpios" +#define XGENE_IRQ_START_PROPERTY "apm,irq-start" + +#define XGENE_DFLT_MAX_NGPIO 22 +#define XGENE_DFLT_MAX_NIRQ 6 +#define XGENE_DFLT_IRQ_START_PIN 8 +#define GPIO_MASK(x) (1U << ((x) % 32)) + +#define MPA_GPIO_INT_LVL 0x0290 +#define MPA_GPIO_OE_ADDR 0x029c +#define MPA_GPIO_OUT_ADDR 0x02a0 +#define MPA_GPIO_IN_ADDR 0x02a4 +#define MPA_GPIO_SEL_LO 0x0294 + +#define GPIO_INT_LEVEL_H 0x000001 +#define GPIO_INT_LEVEL_L 0x000000 + +/** + * struct xgene_gpio_sb - GPIO-Standby private data structure. + * @gc: memory-mapped GPIO controllers. + * @regs: GPIO register base offset + * @irq_domain: GPIO interrupt domain + * @irq_start: GPIO pin that start support interrupt + * @nirq: Number of GPIO pins that supports interrupt + * @parent_irq_base: Start parent HWIRQ + */ +struct xgene_gpio_sb { + struct gpio_chip gc; + void __iomem *regs; + struct irq_domain *irq_domain; + u16 irq_start; + u16 nirq; + u16 parent_irq_base; +}; + +#define HWIRQ_TO_GPIO(priv, hwirq) ((hwirq) + (priv)->irq_start) +#define GPIO_TO_HWIRQ(priv, gpio) ((gpio) - (priv)->irq_start) + +static void xgene_gpio_set_bit(struct gpio_chip *gc, + void __iomem *reg, u32 gpio, int val) +{ + u32 data; + + data = gc->read_reg(reg); + if (val) + data |= GPIO_MASK(gpio); + else + data &= ~GPIO_MASK(gpio); + gc->write_reg(reg, data); +} + +static int xgene_gpio_sb_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct xgene_gpio_sb *priv = irq_data_get_irq_chip_data(d); + int gpio = HWIRQ_TO_GPIO(priv, d->hwirq); + int lvl_type = GPIO_INT_LEVEL_H; + + switch (type & IRQ_TYPE_SENSE_MASK) { + case IRQ_TYPE_EDGE_RISING: + case IRQ_TYPE_LEVEL_HIGH: + lvl_type = GPIO_INT_LEVEL_H; + break; + case IRQ_TYPE_EDGE_FALLING: + case IRQ_TYPE_LEVEL_LOW: + lvl_type = GPIO_INT_LEVEL_L; + break; + default: + break; + } + + xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_SEL_LO, + gpio * 2, 1); + xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_INT_LVL, + d->hwirq, lvl_type); + + /* Propagate IRQ type setting to parent */ + if (type & IRQ_TYPE_EDGE_BOTH) + return irq_chip_set_type_parent(d, IRQ_TYPE_EDGE_RISING); + else + return irq_chip_set_type_parent(d, IRQ_TYPE_LEVEL_HIGH); +} + +static struct irq_chip xgene_gpio_sb_irq_chip = { + .name = "sbgpio", + .irq_eoi = irq_chip_eoi_parent, + .irq_mask = irq_chip_mask_parent, + .irq_unmask = irq_chip_unmask_parent, + .irq_set_type = xgene_gpio_sb_irq_set_type, +}; + +static int xgene_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio) +{ + struct xgene_gpio_sb *priv = gpiochip_get_data(gc); + struct irq_fwspec fwspec; + + if ((gpio < priv->irq_start) || + (gpio > HWIRQ_TO_GPIO(priv, priv->nirq))) + return -ENXIO; + + fwspec.fwnode = gc->parent->fwnode; + fwspec.param_count = 2; + fwspec.param[0] = GPIO_TO_HWIRQ(priv, gpio); + fwspec.param[1] = IRQ_TYPE_NONE; + return irq_create_fwspec_mapping(&fwspec); +} + +static int xgene_gpio_sb_domain_activate(struct irq_domain *d, + struct irq_data *irq_data, + bool reserve) +{ + struct xgene_gpio_sb *priv = d->host_data; + u32 gpio = HWIRQ_TO_GPIO(priv, irq_data->hwirq); + int ret; + + ret = gpiochip_lock_as_irq(&priv->gc, gpio); + if (ret) { + dev_err(priv->gc.parent, + "Unable to configure XGene GPIO standby pin %d as IRQ\n", + gpio); + return ret; + } + + xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_SEL_LO, + gpio * 2, 1); + return 0; +} + +static void xgene_gpio_sb_domain_deactivate(struct irq_domain *d, + struct irq_data *irq_data) +{ + struct xgene_gpio_sb *priv = d->host_data; + u32 gpio = HWIRQ_TO_GPIO(priv, irq_data->hwirq); + + gpiochip_unlock_as_irq(&priv->gc, gpio); + xgene_gpio_set_bit(&priv->gc, priv->regs + MPA_GPIO_SEL_LO, + gpio * 2, 0); +} + +static int xgene_gpio_sb_domain_translate(struct irq_domain *d, + struct irq_fwspec *fwspec, + unsigned long *hwirq, + unsigned int *type) +{ + struct xgene_gpio_sb *priv = d->host_data; + + if ((fwspec->param_count != 2) || + (fwspec->param[0] >= priv->nirq)) + return -EINVAL; + *hwirq = fwspec->param[0]; + *type = fwspec->param[1]; + return 0; +} + +static int xgene_gpio_sb_domain_alloc(struct irq_domain *domain, + unsigned int virq, + unsigned int nr_irqs, void *data) +{ + struct irq_fwspec *fwspec = data; + struct irq_fwspec parent_fwspec; + struct xgene_gpio_sb *priv = domain->host_data; + irq_hw_number_t hwirq; + unsigned int i; + + hwirq = fwspec->param[0]; + for (i = 0; i < nr_irqs; i++) + irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i, + &xgene_gpio_sb_irq_chip, priv); + + parent_fwspec.fwnode = domain->parent->fwnode; + if (is_of_node(parent_fwspec.fwnode)) { + parent_fwspec.param_count = 3; + parent_fwspec.param[0] = 0;/* SPI */ + /* Skip SGIs and PPIs*/ + parent_fwspec.param[1] = hwirq + priv->parent_irq_base - 32; + parent_fwspec.param[2] = fwspec->param[1]; + } else if (is_fwnode_irqchip(parent_fwspec.fwnode)) { + parent_fwspec.param_count = 2; + parent_fwspec.param[0] = hwirq + priv->parent_irq_base; + parent_fwspec.param[1] = fwspec->param[1]; + } else + return -EINVAL; + + return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, + &parent_fwspec); +} + +static const struct irq_domain_ops xgene_gpio_sb_domain_ops = { + .translate = xgene_gpio_sb_domain_translate, + .alloc = xgene_gpio_sb_domain_alloc, + .free = irq_domain_free_irqs_common, + .activate = xgene_gpio_sb_domain_activate, + .deactivate = xgene_gpio_sb_domain_deactivate, +}; + +static int xgene_gpio_sb_probe(struct platform_device *pdev) +{ + struct xgene_gpio_sb *priv; + int ret; + struct resource *res; + void __iomem *regs; + struct irq_domain *parent_domain = NULL; + u32 val32; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + priv->regs = regs; + + ret = platform_get_irq(pdev, 0); + if (ret > 0) { + priv->parent_irq_base = irq_get_irq_data(ret)->hwirq; + parent_domain = irq_get_irq_data(ret)->domain; + } + if (!parent_domain) { + dev_err(&pdev->dev, "unable to obtain parent domain\n"); + return -ENODEV; + } + + ret = bgpio_init(&priv->gc, &pdev->dev, 4, + regs + MPA_GPIO_IN_ADDR, + regs + MPA_GPIO_OUT_ADDR, NULL, + regs + MPA_GPIO_OE_ADDR, NULL, 0); + if (ret) + return ret; + + priv->gc.to_irq = xgene_gpio_sb_to_irq; + + /* Retrieve start irq pin, use default if property not found */ + priv->irq_start = XGENE_DFLT_IRQ_START_PIN; + if (!device_property_read_u32(&pdev->dev, + XGENE_IRQ_START_PROPERTY, &val32)) + priv->irq_start = val32; + + /* Retrieve number irqs, use default if property not found */ + priv->nirq = XGENE_DFLT_MAX_NIRQ; + if (!device_property_read_u32(&pdev->dev, XGENE_NIRQ_PROPERTY, &val32)) + priv->nirq = val32; + + /* Retrieve number gpio, use default if property not found */ + priv->gc.ngpio = XGENE_DFLT_MAX_NGPIO; + if (!device_property_read_u32(&pdev->dev, XGENE_NGPIO_PROPERTY, &val32)) + priv->gc.ngpio = val32; + + dev_info(&pdev->dev, "Support %d gpios, %d irqs start from pin %d\n", + priv->gc.ngpio, priv->nirq, priv->irq_start); + + platform_set_drvdata(pdev, priv); + + priv->irq_domain = irq_domain_create_hierarchy(parent_domain, + 0, priv->nirq, pdev->dev.fwnode, + &xgene_gpio_sb_domain_ops, priv); + if (!priv->irq_domain) + return -ENODEV; + + priv->gc.irq.domain = priv->irq_domain; + + ret = devm_gpiochip_add_data(&pdev->dev, &priv->gc, priv); + if (ret) { + dev_err(&pdev->dev, + "failed to register X-Gene GPIO Standby driver\n"); + irq_domain_remove(priv->irq_domain); + return ret; + } + + dev_info(&pdev->dev, "X-Gene GPIO Standby driver registered\n"); + + if (priv->nirq > 0) { + /* Register interrupt handlers for gpio signaled acpi events */ + acpi_gpiochip_request_interrupts(&priv->gc); + } + + return ret; +} + +static int xgene_gpio_sb_remove(struct platform_device *pdev) +{ + struct xgene_gpio_sb *priv = platform_get_drvdata(pdev); + + if (priv->nirq > 0) { + acpi_gpiochip_free_interrupts(&priv->gc); + } + + irq_domain_remove(priv->irq_domain); + + return 0; +} + +static const struct of_device_id xgene_gpio_sb_of_match[] = { + {.compatible = "apm,xgene-gpio-sb", }, + {}, +}; +MODULE_DEVICE_TABLE(of, xgene_gpio_sb_of_match); + +#ifdef CONFIG_ACPI +static const struct acpi_device_id xgene_gpio_sb_acpi_match[] = { + {"APMC0D15", 0}, + {}, +}; +MODULE_DEVICE_TABLE(acpi, xgene_gpio_sb_acpi_match); +#endif + +static struct platform_driver xgene_gpio_sb_driver = { + .driver = { + .name = "xgene-gpio-sb", + .of_match_table = xgene_gpio_sb_of_match, + .acpi_match_table = ACPI_PTR(xgene_gpio_sb_acpi_match), + }, + .probe = xgene_gpio_sb_probe, + .remove = xgene_gpio_sb_remove, +}; +module_platform_driver(xgene_gpio_sb_driver); + +MODULE_AUTHOR("AppliedMicro"); +MODULE_DESCRIPTION("APM X-Gene GPIO Standby driver"); +MODULE_LICENSE("GPL"); |