diff options
Diffstat (limited to 'kernel/drivers/gpio/gpio-mxs.c')
| -rw-r--r-- | kernel/drivers/gpio/gpio-mxs.c | 370 |
1 files changed, 370 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-mxs.c b/kernel/drivers/gpio/gpio-mxs.c new file mode 100644 index 000000000..84cbda6ac --- /dev/null +++ b/kernel/drivers/gpio/gpio-mxs.c @@ -0,0 +1,370 @@ +/* + * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de> + * Copyright 2008 Juergen Beisert, kernel@pengutronix.de + * + * Based on code from Freescale, + * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved. + * + * 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, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, + * MA 02110-1301, USA. + */ + +#include <linux/err.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/gpio.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/basic_mmio_gpio.h> +#include <linux/module.h> + +#define MXS_SET 0x4 +#define MXS_CLR 0x8 + +#define PINCTRL_DOUT(p) ((is_imx23_gpio(p) ? 0x0500 : 0x0700) + (p->id) * 0x10) +#define PINCTRL_DIN(p) ((is_imx23_gpio(p) ? 0x0600 : 0x0900) + (p->id) * 0x10) +#define PINCTRL_DOE(p) ((is_imx23_gpio(p) ? 0x0700 : 0x0b00) + (p->id) * 0x10) +#define PINCTRL_PIN2IRQ(p) ((is_imx23_gpio(p) ? 0x0800 : 0x1000) + (p->id) * 0x10) +#define PINCTRL_IRQEN(p) ((is_imx23_gpio(p) ? 0x0900 : 0x1100) + (p->id) * 0x10) +#define PINCTRL_IRQLEV(p) ((is_imx23_gpio(p) ? 0x0a00 : 0x1200) + (p->id) * 0x10) +#define PINCTRL_IRQPOL(p) ((is_imx23_gpio(p) ? 0x0b00 : 0x1300) + (p->id) * 0x10) +#define PINCTRL_IRQSTAT(p) ((is_imx23_gpio(p) ? 0x0c00 : 0x1400) + (p->id) * 0x10) + +#define GPIO_INT_FALL_EDGE 0x0 +#define GPIO_INT_LOW_LEV 0x1 +#define GPIO_INT_RISE_EDGE 0x2 +#define GPIO_INT_HIGH_LEV 0x3 +#define GPIO_INT_LEV_MASK (1 << 0) +#define GPIO_INT_POL_MASK (1 << 1) + +enum mxs_gpio_id { + IMX23_GPIO, + IMX28_GPIO, +}; + +struct mxs_gpio_port { + void __iomem *base; + int id; + int irq; + struct irq_domain *domain; + struct bgpio_chip bgc; + enum mxs_gpio_id devid; + u32 both_edges; +}; + +static inline int is_imx23_gpio(struct mxs_gpio_port *port) +{ + return port->devid == IMX23_GPIO; +} + +static inline int is_imx28_gpio(struct mxs_gpio_port *port) +{ + return port->devid == IMX28_GPIO; +} + +/* Note: This driver assumes 32 GPIOs are handled in one register */ + +static int mxs_gpio_set_irq_type(struct irq_data *d, unsigned int type) +{ + u32 val; + u32 pin_mask = 1 << d->hwirq; + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct mxs_gpio_port *port = gc->private; + void __iomem *pin_addr; + int edge; + + port->both_edges &= ~pin_mask; + switch (type) { + case IRQ_TYPE_EDGE_BOTH: + val = gpio_get_value(port->bgc.gc.base + d->hwirq); + if (val) + edge = GPIO_INT_FALL_EDGE; + else + edge = GPIO_INT_RISE_EDGE; + port->both_edges |= pin_mask; + break; + case IRQ_TYPE_EDGE_RISING: + edge = GPIO_INT_RISE_EDGE; + break; + case IRQ_TYPE_EDGE_FALLING: + edge = GPIO_INT_FALL_EDGE; + break; + case IRQ_TYPE_LEVEL_LOW: + edge = GPIO_INT_LOW_LEV; + break; + case IRQ_TYPE_LEVEL_HIGH: + edge = GPIO_INT_HIGH_LEV; + break; + default: + return -EINVAL; + } + + /* set level or edge */ + pin_addr = port->base + PINCTRL_IRQLEV(port); + if (edge & GPIO_INT_LEV_MASK) + writel(pin_mask, pin_addr + MXS_SET); + else + writel(pin_mask, pin_addr + MXS_CLR); + + /* set polarity */ + pin_addr = port->base + PINCTRL_IRQPOL(port); + if (edge & GPIO_INT_POL_MASK) + writel(pin_mask, pin_addr + MXS_SET); + else + writel(pin_mask, pin_addr + MXS_CLR); + + writel(pin_mask, + port->base + PINCTRL_IRQSTAT(port) + MXS_CLR); + + return 0; +} + +static void mxs_flip_edge(struct mxs_gpio_port *port, u32 gpio) +{ + u32 bit, val, edge; + void __iomem *pin_addr; + + bit = 1 << gpio; + + pin_addr = port->base + PINCTRL_IRQPOL(port); + val = readl(pin_addr); + edge = val & bit; + + if (edge) + writel(bit, pin_addr + MXS_CLR); + else + writel(bit, pin_addr + MXS_SET); +} + +/* MXS has one interrupt *per* gpio port */ +static void mxs_gpio_irq_handler(u32 irq, struct irq_desc *desc) +{ + u32 irq_stat; + struct mxs_gpio_port *port = irq_get_handler_data(irq); + + desc->irq_data.chip->irq_ack(&desc->irq_data); + + irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) & + readl(port->base + PINCTRL_IRQEN(port)); + + while (irq_stat != 0) { + int irqoffset = fls(irq_stat) - 1; + if (port->both_edges & (1 << irqoffset)) + mxs_flip_edge(port, irqoffset); + + generic_handle_irq(irq_find_mapping(port->domain, irqoffset)); + irq_stat &= ~(1 << irqoffset); + } +} + +/* + * Set interrupt number "irq" in the GPIO as a wake-up source. + * While system is running, all registered GPIO interrupts need to have + * wake-up enabled. When system is suspended, only selected GPIO interrupts + * need to have wake-up enabled. + * @param irq interrupt source number + * @param enable enable as wake-up if equal to non-zero + * @return This function returns 0 on success. + */ +static int mxs_gpio_set_wake_irq(struct irq_data *d, unsigned int enable) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct mxs_gpio_port *port = gc->private; + + if (enable) + enable_irq_wake(port->irq); + else + disable_irq_wake(port->irq); + + return 0; +} + +static void __init mxs_gpio_init_gc(struct mxs_gpio_port *port, int irq_base) +{ + struct irq_chip_generic *gc; + struct irq_chip_type *ct; + + gc = irq_alloc_generic_chip("gpio-mxs", 1, irq_base, + port->base, handle_level_irq); + gc->private = port; + + ct = gc->chip_types; + ct->chip.irq_ack = irq_gc_ack_set_bit; + ct->chip.irq_mask = irq_gc_mask_clr_bit; + ct->chip.irq_unmask = irq_gc_mask_set_bit; + ct->chip.irq_set_type = mxs_gpio_set_irq_type; + ct->chip.irq_set_wake = mxs_gpio_set_wake_irq; + ct->regs.ack = PINCTRL_IRQSTAT(port) + MXS_CLR; + ct->regs.mask = PINCTRL_IRQEN(port); + + irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_NESTED_LOCK, + IRQ_NOREQUEST, 0); +} + +static int mxs_gpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + struct mxs_gpio_port *port = + container_of(bgc, struct mxs_gpio_port, bgc); + + return irq_find_mapping(port->domain, offset); +} + +static int mxs_gpio_get_direction(struct gpio_chip *gc, unsigned offset) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + struct mxs_gpio_port *port = + container_of(bgc, struct mxs_gpio_port, bgc); + u32 mask = 1 << offset; + u32 dir; + + dir = readl(port->base + PINCTRL_DOE(port)); + return !(dir & mask); +} + +static struct platform_device_id mxs_gpio_ids[] = { + { + .name = "imx23-gpio", + .driver_data = IMX23_GPIO, + }, { + .name = "imx28-gpio", + .driver_data = IMX28_GPIO, + }, { + /* sentinel */ + } +}; +MODULE_DEVICE_TABLE(platform, mxs_gpio_ids); + +static const struct of_device_id mxs_gpio_dt_ids[] = { + { .compatible = "fsl,imx23-gpio", .data = (void *) IMX23_GPIO, }, + { .compatible = "fsl,imx28-gpio", .data = (void *) IMX28_GPIO, }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, mxs_gpio_dt_ids); + +static int mxs_gpio_probe(struct platform_device *pdev) +{ + const struct of_device_id *of_id = + of_match_device(mxs_gpio_dt_ids, &pdev->dev); + struct device_node *np = pdev->dev.of_node; + struct device_node *parent; + static void __iomem *base; + struct mxs_gpio_port *port; + int irq_base; + int err; + + port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL); + if (!port) + return -ENOMEM; + + port->id = of_alias_get_id(np, "gpio"); + if (port->id < 0) + return port->id; + port->devid = (enum mxs_gpio_id) of_id->data; + port->irq = platform_get_irq(pdev, 0); + if (port->irq < 0) + return port->irq; + + /* + * map memory region only once, as all the gpio ports + * share the same one + */ + if (!base) { + parent = of_get_parent(np); + base = of_iomap(parent, 0); + of_node_put(parent); + if (!base) + return -EADDRNOTAVAIL; + } + port->base = base; + + /* + * select the pin interrupt functionality but initially + * disable the interrupts + */ + writel(~0U, port->base + PINCTRL_PIN2IRQ(port)); + writel(0, port->base + PINCTRL_IRQEN(port)); + + /* clear address has to be used to clear IRQSTAT bits */ + writel(~0U, port->base + PINCTRL_IRQSTAT(port) + MXS_CLR); + + irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id()); + if (irq_base < 0) + return irq_base; + + port->domain = irq_domain_add_legacy(np, 32, irq_base, 0, + &irq_domain_simple_ops, NULL); + if (!port->domain) { + err = -ENODEV; + goto out_irqdesc_free; + } + + /* gpio-mxs can be a generic irq chip */ + mxs_gpio_init_gc(port, irq_base); + + /* setup one handler for each entry */ + irq_set_chained_handler(port->irq, mxs_gpio_irq_handler); + irq_set_handler_data(port->irq, port); + + err = bgpio_init(&port->bgc, &pdev->dev, 4, + port->base + PINCTRL_DIN(port), + port->base + PINCTRL_DOUT(port) + MXS_SET, + port->base + PINCTRL_DOUT(port) + MXS_CLR, + port->base + PINCTRL_DOE(port), NULL, 0); + if (err) + goto out_irqdesc_free; + + port->bgc.gc.to_irq = mxs_gpio_to_irq; + port->bgc.gc.get_direction = mxs_gpio_get_direction; + port->bgc.gc.base = port->id * 32; + + err = gpiochip_add(&port->bgc.gc); + if (err) + goto out_bgpio_remove; + + return 0; + +out_bgpio_remove: + bgpio_remove(&port->bgc); +out_irqdesc_free: + irq_free_descs(irq_base, 32); + return err; +} + +static struct platform_driver mxs_gpio_driver = { + .driver = { + .name = "gpio-mxs", + .of_match_table = mxs_gpio_dt_ids, + }, + .probe = mxs_gpio_probe, + .id_table = mxs_gpio_ids, +}; + +static int __init mxs_gpio_init(void) +{ + return platform_driver_register(&mxs_gpio_driver); +} +postcore_initcall(mxs_gpio_init); + +MODULE_AUTHOR("Freescale Semiconductor, " + "Daniel Mack <danielncaiaq.de>, " + "Juergen Beisert <kernel@pengutronix.de>"); +MODULE_DESCRIPTION("Freescale MXS GPIO"); +MODULE_LICENSE("GPL"); |