diff options
Diffstat (limited to 'kernel/drivers/gpio/gpio-mxc.c')
| -rw-r--r-- | kernel/drivers/gpio/gpio-mxc.c | 515 |
1 files changed, 515 insertions, 0 deletions
diff --git a/kernel/drivers/gpio/gpio-mxc.c b/kernel/drivers/gpio/gpio-mxc.c new file mode 100644 index 000000000..9f7446a7a --- /dev/null +++ b/kernel/drivers/gpio/gpio-mxc.c @@ -0,0 +1,515 @@ +/* + * 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/irqchip/chained_irq.h> +#include <linux/gpio.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/basic_mmio_gpio.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/module.h> +#include <asm-generic/bug.h> + +enum mxc_gpio_hwtype { + IMX1_GPIO, /* runs on i.mx1 */ + IMX21_GPIO, /* runs on i.mx21 and i.mx27 */ + IMX31_GPIO, /* runs on i.mx31 */ + IMX35_GPIO, /* runs on all other i.mx */ +}; + +/* device type dependent stuff */ +struct mxc_gpio_hwdata { + unsigned dr_reg; + unsigned gdir_reg; + unsigned psr_reg; + unsigned icr1_reg; + unsigned icr2_reg; + unsigned imr_reg; + unsigned isr_reg; + int edge_sel_reg; + unsigned low_level; + unsigned high_level; + unsigned rise_edge; + unsigned fall_edge; +}; + +struct mxc_gpio_port { + struct list_head node; + void __iomem *base; + int irq; + int irq_high; + struct irq_domain *domain; + struct bgpio_chip bgc; + u32 both_edges; +}; + +static struct mxc_gpio_hwdata imx1_imx21_gpio_hwdata = { + .dr_reg = 0x1c, + .gdir_reg = 0x00, + .psr_reg = 0x24, + .icr1_reg = 0x28, + .icr2_reg = 0x2c, + .imr_reg = 0x30, + .isr_reg = 0x34, + .edge_sel_reg = -EINVAL, + .low_level = 0x03, + .high_level = 0x02, + .rise_edge = 0x00, + .fall_edge = 0x01, +}; + +static struct mxc_gpio_hwdata imx31_gpio_hwdata = { + .dr_reg = 0x00, + .gdir_reg = 0x04, + .psr_reg = 0x08, + .icr1_reg = 0x0c, + .icr2_reg = 0x10, + .imr_reg = 0x14, + .isr_reg = 0x18, + .edge_sel_reg = -EINVAL, + .low_level = 0x00, + .high_level = 0x01, + .rise_edge = 0x02, + .fall_edge = 0x03, +}; + +static struct mxc_gpio_hwdata imx35_gpio_hwdata = { + .dr_reg = 0x00, + .gdir_reg = 0x04, + .psr_reg = 0x08, + .icr1_reg = 0x0c, + .icr2_reg = 0x10, + .imr_reg = 0x14, + .isr_reg = 0x18, + .edge_sel_reg = 0x1c, + .low_level = 0x00, + .high_level = 0x01, + .rise_edge = 0x02, + .fall_edge = 0x03, +}; + +static enum mxc_gpio_hwtype mxc_gpio_hwtype; +static struct mxc_gpio_hwdata *mxc_gpio_hwdata; + +#define GPIO_DR (mxc_gpio_hwdata->dr_reg) +#define GPIO_GDIR (mxc_gpio_hwdata->gdir_reg) +#define GPIO_PSR (mxc_gpio_hwdata->psr_reg) +#define GPIO_ICR1 (mxc_gpio_hwdata->icr1_reg) +#define GPIO_ICR2 (mxc_gpio_hwdata->icr2_reg) +#define GPIO_IMR (mxc_gpio_hwdata->imr_reg) +#define GPIO_ISR (mxc_gpio_hwdata->isr_reg) +#define GPIO_EDGE_SEL (mxc_gpio_hwdata->edge_sel_reg) + +#define GPIO_INT_LOW_LEV (mxc_gpio_hwdata->low_level) +#define GPIO_INT_HIGH_LEV (mxc_gpio_hwdata->high_level) +#define GPIO_INT_RISE_EDGE (mxc_gpio_hwdata->rise_edge) +#define GPIO_INT_FALL_EDGE (mxc_gpio_hwdata->fall_edge) +#define GPIO_INT_BOTH_EDGES 0x4 + +static struct platform_device_id mxc_gpio_devtype[] = { + { + .name = "imx1-gpio", + .driver_data = IMX1_GPIO, + }, { + .name = "imx21-gpio", + .driver_data = IMX21_GPIO, + }, { + .name = "imx31-gpio", + .driver_data = IMX31_GPIO, + }, { + .name = "imx35-gpio", + .driver_data = IMX35_GPIO, + }, { + /* sentinel */ + } +}; + +static const struct of_device_id mxc_gpio_dt_ids[] = { + { .compatible = "fsl,imx1-gpio", .data = &mxc_gpio_devtype[IMX1_GPIO], }, + { .compatible = "fsl,imx21-gpio", .data = &mxc_gpio_devtype[IMX21_GPIO], }, + { .compatible = "fsl,imx31-gpio", .data = &mxc_gpio_devtype[IMX31_GPIO], }, + { .compatible = "fsl,imx35-gpio", .data = &mxc_gpio_devtype[IMX35_GPIO], }, + { /* sentinel */ } +}; + +/* + * MX2 has one interrupt *for all* gpio ports. The list is used + * to save the references to all ports, so that mx2_gpio_irq_handler + * can walk through all interrupt status registers. + */ +static LIST_HEAD(mxc_gpio_ports); + +/* Note: This driver assumes 32 GPIOs are handled in one register */ + +static int gpio_set_irq_type(struct irq_data *d, u32 type) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct mxc_gpio_port *port = gc->private; + u32 bit, val; + u32 gpio_idx = d->hwirq; + u32 gpio = port->bgc.gc.base + gpio_idx; + int edge; + void __iomem *reg = port->base; + + port->both_edges &= ~(1 << gpio_idx); + switch (type) { + 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_EDGE_BOTH: + if (GPIO_EDGE_SEL >= 0) { + edge = GPIO_INT_BOTH_EDGES; + } else { + val = gpio_get_value(gpio); + if (val) { + edge = GPIO_INT_LOW_LEV; + pr_debug("mxc: set GPIO %d to low trigger\n", gpio); + } else { + edge = GPIO_INT_HIGH_LEV; + pr_debug("mxc: set GPIO %d to high trigger\n", gpio); + } + port->both_edges |= 1 << gpio_idx; + } + 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; + } + + if (GPIO_EDGE_SEL >= 0) { + val = readl(port->base + GPIO_EDGE_SEL); + if (edge == GPIO_INT_BOTH_EDGES) + writel(val | (1 << gpio_idx), + port->base + GPIO_EDGE_SEL); + else + writel(val & ~(1 << gpio_idx), + port->base + GPIO_EDGE_SEL); + } + + if (edge != GPIO_INT_BOTH_EDGES) { + reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */ + bit = gpio_idx & 0xf; + val = readl(reg) & ~(0x3 << (bit << 1)); + writel(val | (edge << (bit << 1)), reg); + } + + writel(1 << gpio_idx, port->base + GPIO_ISR); + + return 0; +} + +static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio) +{ + void __iomem *reg = port->base; + u32 bit, val; + int edge; + + reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */ + bit = gpio & 0xf; + val = readl(reg); + edge = (val >> (bit << 1)) & 3; + val &= ~(0x3 << (bit << 1)); + if (edge == GPIO_INT_HIGH_LEV) { + edge = GPIO_INT_LOW_LEV; + pr_debug("mxc: switch GPIO %d to low trigger\n", gpio); + } else if (edge == GPIO_INT_LOW_LEV) { + edge = GPIO_INT_HIGH_LEV; + pr_debug("mxc: switch GPIO %d to high trigger\n", gpio); + } else { + pr_err("mxc: invalid configuration for GPIO %d: %x\n", + gpio, edge); + return; + } + writel(val | (edge << (bit << 1)), reg); +} + +/* handle 32 interrupts in one status register */ +static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat) +{ + while (irq_stat != 0) { + int irqoffset = fls(irq_stat) - 1; + + if (port->both_edges & (1 << irqoffset)) + mxc_flip_edge(port, irqoffset); + + generic_handle_irq(irq_find_mapping(port->domain, irqoffset)); + + irq_stat &= ~(1 << irqoffset); + } +} + +/* MX1 and MX3 has one interrupt *per* gpio port */ +static void mx3_gpio_irq_handler(u32 irq, struct irq_desc *desc) +{ + u32 irq_stat; + struct mxc_gpio_port *port = irq_get_handler_data(irq); + struct irq_chip *chip = irq_get_chip(irq); + + chained_irq_enter(chip, desc); + + irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR); + + mxc_gpio_irq_handler(port, irq_stat); + + chained_irq_exit(chip, desc); +} + +/* MX2 has one interrupt *for all* gpio ports */ +static void mx2_gpio_irq_handler(u32 irq, struct irq_desc *desc) +{ + u32 irq_msk, irq_stat; + struct mxc_gpio_port *port; + struct irq_chip *chip = irq_get_chip(irq); + + chained_irq_enter(chip, desc); + + /* walk through all interrupt status registers */ + list_for_each_entry(port, &mxc_gpio_ports, node) { + irq_msk = readl(port->base + GPIO_IMR); + if (!irq_msk) + continue; + + irq_stat = readl(port->base + GPIO_ISR) & irq_msk; + if (irq_stat) + mxc_gpio_irq_handler(port, irq_stat); + } + chained_irq_exit(chip, desc); +} + +/* + * 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 gpio_set_wake_irq(struct irq_data *d, u32 enable) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct mxc_gpio_port *port = gc->private; + u32 gpio_idx = d->hwirq; + + if (enable) { + if (port->irq_high && (gpio_idx >= 16)) + enable_irq_wake(port->irq_high); + else + enable_irq_wake(port->irq); + } else { + if (port->irq_high && (gpio_idx >= 16)) + disable_irq_wake(port->irq_high); + else + disable_irq_wake(port->irq); + } + + return 0; +} + +static void __init mxc_gpio_init_gc(struct mxc_gpio_port *port, int irq_base) +{ + struct irq_chip_generic *gc; + struct irq_chip_type *ct; + + gc = irq_alloc_generic_chip("gpio-mxc", 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 = gpio_set_irq_type; + ct->chip.irq_set_wake = gpio_set_wake_irq; + ct->regs.ack = GPIO_ISR; + ct->regs.mask = GPIO_IMR; + + irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_NESTED_LOCK, + IRQ_NOREQUEST, 0); +} + +static void mxc_gpio_get_hw(struct platform_device *pdev) +{ + const struct of_device_id *of_id = + of_match_device(mxc_gpio_dt_ids, &pdev->dev); + enum mxc_gpio_hwtype hwtype; + + if (of_id) + pdev->id_entry = of_id->data; + hwtype = pdev->id_entry->driver_data; + + if (mxc_gpio_hwtype) { + /* + * The driver works with a reasonable presupposition, + * that is all gpio ports must be the same type when + * running on one soc. + */ + BUG_ON(mxc_gpio_hwtype != hwtype); + return; + } + + if (hwtype == IMX35_GPIO) + mxc_gpio_hwdata = &imx35_gpio_hwdata; + else if (hwtype == IMX31_GPIO) + mxc_gpio_hwdata = &imx31_gpio_hwdata; + else + mxc_gpio_hwdata = &imx1_imx21_gpio_hwdata; + + mxc_gpio_hwtype = hwtype; +} + +static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + struct mxc_gpio_port *port = + container_of(bgc, struct mxc_gpio_port, bgc); + + return irq_find_mapping(port->domain, offset); +} + +static int mxc_gpio_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct mxc_gpio_port *port; + struct resource *iores; + int irq_base; + int err; + + mxc_gpio_get_hw(pdev); + + port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL); + if (!port) + return -ENOMEM; + + iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); + port->base = devm_ioremap_resource(&pdev->dev, iores); + if (IS_ERR(port->base)) + return PTR_ERR(port->base); + + port->irq_high = platform_get_irq(pdev, 1); + port->irq = platform_get_irq(pdev, 0); + if (port->irq < 0) + return port->irq; + + /* disable the interrupt and clear the status */ + writel(0, port->base + GPIO_IMR); + writel(~0, port->base + GPIO_ISR); + + if (mxc_gpio_hwtype == IMX21_GPIO) { + /* + * Setup one handler for all GPIO interrupts. Actually setting + * the handler is needed only once, but doing it for every port + * is more robust and easier. + */ + irq_set_chained_handler(port->irq, mx2_gpio_irq_handler); + } else { + /* setup one handler for each entry */ + irq_set_chained_handler(port->irq, mx3_gpio_irq_handler); + irq_set_handler_data(port->irq, port); + if (port->irq_high > 0) { + /* setup handler for GPIO 16 to 31 */ + irq_set_chained_handler(port->irq_high, + mx3_gpio_irq_handler); + irq_set_handler_data(port->irq_high, port); + } + } + + err = bgpio_init(&port->bgc, &pdev->dev, 4, + port->base + GPIO_PSR, + port->base + GPIO_DR, NULL, + port->base + GPIO_GDIR, NULL, 0); + if (err) + goto out_bgio; + + port->bgc.gc.to_irq = mxc_gpio_to_irq; + port->bgc.gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 : + pdev->id * 32; + + err = gpiochip_add(&port->bgc.gc); + if (err) + goto out_bgpio_remove; + + irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id()); + if (irq_base < 0) { + err = irq_base; + goto out_gpiochip_remove; + } + + 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-mxc can be a generic irq chip */ + mxc_gpio_init_gc(port, irq_base); + + list_add_tail(&port->node, &mxc_gpio_ports); + + return 0; + +out_irqdesc_free: + irq_free_descs(irq_base, 32); +out_gpiochip_remove: + gpiochip_remove(&port->bgc.gc); +out_bgpio_remove: + bgpio_remove(&port->bgc); +out_bgio: + dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err); + return err; +} + +static struct platform_driver mxc_gpio_driver = { + .driver = { + .name = "gpio-mxc", + .of_match_table = mxc_gpio_dt_ids, + }, + .probe = mxc_gpio_probe, + .id_table = mxc_gpio_devtype, +}; + +static int __init gpio_mxc_init(void) +{ + return platform_driver_register(&mxc_gpio_driver); +} +postcore_initcall(gpio_mxc_init); + +MODULE_AUTHOR("Freescale Semiconductor, " + "Daniel Mack <danielncaiaq.de>, " + "Juergen Beisert <kernel@pengutronix.de>"); +MODULE_DESCRIPTION("Freescale MXC GPIO"); +MODULE_LICENSE("GPL"); |