diff options
Diffstat (limited to 'kernel/drivers/gpio/gpio-em.c')
| -rw-r--r-- | kernel/drivers/gpio/gpio-em.c | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-em.c b/kernel/drivers/gpio/gpio-em.c new file mode 100644 index 000000000..3cfcfc620 --- /dev/null +++ b/kernel/drivers/gpio/gpio-em.c @@ -0,0 +1,443 @@ +/* + * Emma Mobile GPIO Support - GIO + * + * Copyright (C) 2012 Magnus Damm + * + * 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 + * + * 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, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/bitops.h> +#include <linux/err.h> +#include <linux/gpio.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/pinctrl/consumer.h> +#include <linux/platform_data/gpio-em.h> + +struct em_gio_priv { + void __iomem *base0; + void __iomem *base1; + spinlock_t sense_lock; + struct platform_device *pdev; + struct gpio_chip gpio_chip; + struct irq_chip irq_chip; + struct irq_domain *irq_domain; +}; + +#define GIO_E1 0x00 +#define GIO_E0 0x04 +#define GIO_EM 0x04 +#define GIO_OL 0x08 +#define GIO_OH 0x0c +#define GIO_I 0x10 +#define GIO_IIA 0x14 +#define GIO_IEN 0x18 +#define GIO_IDS 0x1c +#define GIO_IIM 0x1c +#define GIO_RAW 0x20 +#define GIO_MST 0x24 +#define GIO_IIR 0x28 + +#define GIO_IDT0 0x40 +#define GIO_IDT1 0x44 +#define GIO_IDT2 0x48 +#define GIO_IDT3 0x4c +#define GIO_RAWBL 0x50 +#define GIO_RAWBH 0x54 +#define GIO_IRBL 0x58 +#define GIO_IRBH 0x5c + +#define GIO_IDT(n) (GIO_IDT0 + ((n) * 4)) + +static inline unsigned long em_gio_read(struct em_gio_priv *p, int offs) +{ + if (offs < GIO_IDT0) + return ioread32(p->base0 + offs); + else + return ioread32(p->base1 + (offs - GIO_IDT0)); +} + +static inline void em_gio_write(struct em_gio_priv *p, int offs, + unsigned long value) +{ + if (offs < GIO_IDT0) + iowrite32(value, p->base0 + offs); + else + iowrite32(value, p->base1 + (offs - GIO_IDT0)); +} + +static void em_gio_irq_disable(struct irq_data *d) +{ + struct em_gio_priv *p = irq_data_get_irq_chip_data(d); + + em_gio_write(p, GIO_IDS, BIT(irqd_to_hwirq(d))); +} + +static void em_gio_irq_enable(struct irq_data *d) +{ + struct em_gio_priv *p = irq_data_get_irq_chip_data(d); + + em_gio_write(p, GIO_IEN, BIT(irqd_to_hwirq(d))); +} + +static int em_gio_irq_reqres(struct irq_data *d) +{ + struct em_gio_priv *p = irq_data_get_irq_chip_data(d); + + if (gpiochip_lock_as_irq(&p->gpio_chip, irqd_to_hwirq(d))) { + dev_err(p->gpio_chip.dev, + "unable to lock HW IRQ %lu for IRQ\n", + irqd_to_hwirq(d)); + return -EINVAL; + } + return 0; +} + +static void em_gio_irq_relres(struct irq_data *d) +{ + struct em_gio_priv *p = irq_data_get_irq_chip_data(d); + + gpiochip_unlock_as_irq(&p->gpio_chip, irqd_to_hwirq(d)); +} + + +#define GIO_ASYNC(x) (x + 8) + +static unsigned char em_gio_sense_table[IRQ_TYPE_SENSE_MASK + 1] = { + [IRQ_TYPE_EDGE_RISING] = GIO_ASYNC(0x00), + [IRQ_TYPE_EDGE_FALLING] = GIO_ASYNC(0x01), + [IRQ_TYPE_LEVEL_HIGH] = GIO_ASYNC(0x02), + [IRQ_TYPE_LEVEL_LOW] = GIO_ASYNC(0x03), + [IRQ_TYPE_EDGE_BOTH] = GIO_ASYNC(0x04), +}; + +static int em_gio_irq_set_type(struct irq_data *d, unsigned int type) +{ + unsigned char value = em_gio_sense_table[type & IRQ_TYPE_SENSE_MASK]; + struct em_gio_priv *p = irq_data_get_irq_chip_data(d); + unsigned int reg, offset, shift; + unsigned long flags; + unsigned long tmp; + + if (!value) + return -EINVAL; + + offset = irqd_to_hwirq(d); + + pr_debug("gio: sense irq = %d, mode = %d\n", offset, value); + + /* 8 x 4 bit fields in 4 IDT registers */ + reg = GIO_IDT(offset >> 3); + shift = (offset & 0x07) << 4; + + spin_lock_irqsave(&p->sense_lock, flags); + + /* disable the interrupt in IIA */ + tmp = em_gio_read(p, GIO_IIA); + tmp &= ~BIT(offset); + em_gio_write(p, GIO_IIA, tmp); + + /* change the sense setting in IDT */ + tmp = em_gio_read(p, reg); + tmp &= ~(0xf << shift); + tmp |= value << shift; + em_gio_write(p, reg, tmp); + + /* clear pending interrupts */ + em_gio_write(p, GIO_IIR, BIT(offset)); + + /* enable the interrupt in IIA */ + tmp = em_gio_read(p, GIO_IIA); + tmp |= BIT(offset); + em_gio_write(p, GIO_IIA, tmp); + + spin_unlock_irqrestore(&p->sense_lock, flags); + + return 0; +} + +static irqreturn_t em_gio_irq_handler(int irq, void *dev_id) +{ + struct em_gio_priv *p = dev_id; + unsigned long pending; + unsigned int offset, irqs_handled = 0; + + while ((pending = em_gio_read(p, GIO_MST))) { + offset = __ffs(pending); + em_gio_write(p, GIO_IIR, BIT(offset)); + generic_handle_irq(irq_find_mapping(p->irq_domain, offset)); + irqs_handled++; + } + + return irqs_handled ? IRQ_HANDLED : IRQ_NONE; +} + +static inline struct em_gio_priv *gpio_to_priv(struct gpio_chip *chip) +{ + return container_of(chip, struct em_gio_priv, gpio_chip); +} + +static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset) +{ + em_gio_write(gpio_to_priv(chip), GIO_E0, BIT(offset)); + return 0; +} + +static int em_gio_get(struct gpio_chip *chip, unsigned offset) +{ + return (int)(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset)); +} + +static void __em_gio_set(struct gpio_chip *chip, unsigned int reg, + unsigned shift, int value) +{ + /* upper 16 bits contains mask and lower 16 actual value */ + em_gio_write(gpio_to_priv(chip), reg, + (BIT(shift + 16)) | (value << shift)); +} + +static void em_gio_set(struct gpio_chip *chip, unsigned offset, int value) +{ + /* output is split into two registers */ + if (offset < 16) + __em_gio_set(chip, GIO_OL, offset, value); + else + __em_gio_set(chip, GIO_OH, offset - 16, value); +} + +static int em_gio_direction_output(struct gpio_chip *chip, unsigned offset, + int value) +{ + /* write GPIO value to output before selecting output mode of pin */ + em_gio_set(chip, offset, value); + em_gio_write(gpio_to_priv(chip), GIO_E1, BIT(offset)); + return 0; +} + +static int em_gio_to_irq(struct gpio_chip *chip, unsigned offset) +{ + return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset); +} + +static int em_gio_request(struct gpio_chip *chip, unsigned offset) +{ + return pinctrl_request_gpio(chip->base + offset); +} + +static void em_gio_free(struct gpio_chip *chip, unsigned offset) +{ + pinctrl_free_gpio(chip->base + offset); + + /* Set the GPIO as an input to ensure that the next GPIO request won't + * drive the GPIO pin as an output. + */ + em_gio_direction_input(chip, offset); +} + +static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int irq, + irq_hw_number_t hwirq) +{ + struct em_gio_priv *p = h->host_data; + + pr_debug("gio: map hw irq = %d, irq = %d\n", (int)hwirq, irq); + + irq_set_chip_data(irq, h->host_data); + irq_set_chip_and_handler(irq, &p->irq_chip, handle_level_irq); + set_irq_flags(irq, IRQF_VALID); /* kill me now */ + return 0; +} + +static struct irq_domain_ops em_gio_irq_domain_ops = { + .map = em_gio_irq_domain_map, + .xlate = irq_domain_xlate_twocell, +}; + +static int em_gio_probe(struct platform_device *pdev) +{ + struct gpio_em_config pdata_dt; + struct gpio_em_config *pdata = dev_get_platdata(&pdev->dev); + struct em_gio_priv *p; + struct resource *io[2], *irq[2]; + struct gpio_chip *gpio_chip; + struct irq_chip *irq_chip; + const char *name = dev_name(&pdev->dev); + int ret; + + p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL); + if (!p) { + ret = -ENOMEM; + goto err0; + } + + p->pdev = pdev; + platform_set_drvdata(pdev, p); + spin_lock_init(&p->sense_lock); + + io[0] = platform_get_resource(pdev, IORESOURCE_MEM, 0); + io[1] = platform_get_resource(pdev, IORESOURCE_MEM, 1); + irq[0] = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + irq[1] = platform_get_resource(pdev, IORESOURCE_IRQ, 1); + + if (!io[0] || !io[1] || !irq[0] || !irq[1]) { + dev_err(&pdev->dev, "missing IRQ or IOMEM\n"); + ret = -EINVAL; + goto err0; + } + + p->base0 = devm_ioremap_nocache(&pdev->dev, io[0]->start, + resource_size(io[0])); + if (!p->base0) { + dev_err(&pdev->dev, "failed to remap low I/O memory\n"); + ret = -ENXIO; + goto err0; + } + + p->base1 = devm_ioremap_nocache(&pdev->dev, io[1]->start, + resource_size(io[1])); + if (!p->base1) { + dev_err(&pdev->dev, "failed to remap high I/O memory\n"); + ret = -ENXIO; + goto err0; + } + + if (!pdata) { + memset(&pdata_dt, 0, sizeof(pdata_dt)); + pdata = &pdata_dt; + + if (of_property_read_u32(pdev->dev.of_node, "ngpios", + &pdata->number_of_pins)) { + dev_err(&pdev->dev, "Missing ngpios OF property\n"); + ret = -EINVAL; + goto err0; + } + + pdata->gpio_base = -1; + } + + gpio_chip = &p->gpio_chip; + gpio_chip->of_node = pdev->dev.of_node; + gpio_chip->direction_input = em_gio_direction_input; + gpio_chip->get = em_gio_get; + gpio_chip->direction_output = em_gio_direction_output; + gpio_chip->set = em_gio_set; + gpio_chip->to_irq = em_gio_to_irq; + gpio_chip->request = em_gio_request; + gpio_chip->free = em_gio_free; + gpio_chip->label = name; + gpio_chip->dev = &pdev->dev; + gpio_chip->owner = THIS_MODULE; + gpio_chip->base = pdata->gpio_base; + gpio_chip->ngpio = pdata->number_of_pins; + + irq_chip = &p->irq_chip; + irq_chip->name = name; + irq_chip->irq_mask = em_gio_irq_disable; + irq_chip->irq_unmask = em_gio_irq_enable; + irq_chip->irq_set_type = em_gio_irq_set_type; + irq_chip->irq_request_resources = em_gio_irq_reqres; + irq_chip->irq_release_resources = em_gio_irq_relres; + irq_chip->flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND; + + p->irq_domain = irq_domain_add_simple(pdev->dev.of_node, + pdata->number_of_pins, + pdata->irq_base, + &em_gio_irq_domain_ops, p); + if (!p->irq_domain) { + ret = -ENXIO; + dev_err(&pdev->dev, "cannot initialize irq domain\n"); + goto err0; + } + + if (devm_request_irq(&pdev->dev, irq[0]->start, + em_gio_irq_handler, 0, name, p)) { + dev_err(&pdev->dev, "failed to request low IRQ\n"); + ret = -ENOENT; + goto err1; + } + + if (devm_request_irq(&pdev->dev, irq[1]->start, + em_gio_irq_handler, 0, name, p)) { + dev_err(&pdev->dev, "failed to request high IRQ\n"); + ret = -ENOENT; + goto err1; + } + + ret = gpiochip_add(gpio_chip); + if (ret) { + dev_err(&pdev->dev, "failed to add GPIO controller\n"); + goto err1; + } + + if (pdata->pctl_name) { + ret = gpiochip_add_pin_range(gpio_chip, pdata->pctl_name, 0, + gpio_chip->base, gpio_chip->ngpio); + if (ret < 0) + dev_warn(&pdev->dev, "failed to add pin range\n"); + } + return 0; + +err1: + irq_domain_remove(p->irq_domain); +err0: + return ret; +} + +static int em_gio_remove(struct platform_device *pdev) +{ + struct em_gio_priv *p = platform_get_drvdata(pdev); + + gpiochip_remove(&p->gpio_chip); + + irq_domain_remove(p->irq_domain); + return 0; +} + +static const struct of_device_id em_gio_dt_ids[] = { + { .compatible = "renesas,em-gio", }, + {}, +}; +MODULE_DEVICE_TABLE(of, em_gio_dt_ids); + +static struct platform_driver em_gio_device_driver = { + .probe = em_gio_probe, + .remove = em_gio_remove, + .driver = { + .name = "em_gio", + .of_match_table = em_gio_dt_ids, + } +}; + +static int __init em_gio_init(void) +{ + return platform_driver_register(&em_gio_device_driver); +} +postcore_initcall(em_gio_init); + +static void __exit em_gio_exit(void) +{ + platform_driver_unregister(&em_gio_device_driver); +} +module_exit(em_gio_exit); + +MODULE_AUTHOR("Magnus Damm"); +MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver"); +MODULE_LICENSE("GPL v2"); |