diff options
Diffstat (limited to 'drivers/gpio/gpio-mxc.c')
| -rw-r--r-- | drivers/gpio/gpio-mxc.c | 566 |
1 files changed, 566 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c new file mode 100644 index 000000000..853d9aa6b --- /dev/null +++ b/drivers/gpio/gpio-mxc.c @@ -0,0 +1,566 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de> +// Copyright 2008 Juergen Beisert, kernel@pengutronix.de +// +// Based on code from Freescale Semiconductor, +// Authors: Daniel Mack, Juergen Beisert. +// Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved. + +#include <linux/clk.h> +#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/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/syscore_ops.h> +#include <linux/gpio/driver.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/bug.h> + +/* 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_reg_saved { + u32 icr1; + u32 icr2; + u32 imr; + u32 gdir; + u32 edge_sel; + u32 dr; +}; + +struct mxc_gpio_port { + struct list_head node; + void __iomem *base; + struct clk *clk; + int irq; + int irq_high; + struct irq_domain *domain; + struct gpio_chip gc; + struct device *dev; + u32 both_edges; + struct mxc_gpio_reg_saved gpio_saved_reg; + bool power_off; + const struct mxc_gpio_hwdata *hwdata; +}; + +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, +}; + +#define GPIO_DR (port->hwdata->dr_reg) +#define GPIO_GDIR (port->hwdata->gdir_reg) +#define GPIO_PSR (port->hwdata->psr_reg) +#define GPIO_ICR1 (port->hwdata->icr1_reg) +#define GPIO_ICR2 (port->hwdata->icr2_reg) +#define GPIO_IMR (port->hwdata->imr_reg) +#define GPIO_ISR (port->hwdata->isr_reg) +#define GPIO_EDGE_SEL (port->hwdata->edge_sel_reg) + +#define GPIO_INT_LOW_LEV (port->hwdata->low_level) +#define GPIO_INT_HIGH_LEV (port->hwdata->high_level) +#define GPIO_INT_RISE_EDGE (port->hwdata->rise_edge) +#define GPIO_INT_FALL_EDGE (port->hwdata->fall_edge) +#define GPIO_INT_BOTH_EDGES 0x4 + +static const struct of_device_id mxc_gpio_dt_ids[] = { + { .compatible = "fsl,imx1-gpio", .data = &imx1_imx21_gpio_hwdata }, + { .compatible = "fsl,imx21-gpio", .data = &imx1_imx21_gpio_hwdata }, + { .compatible = "fsl,imx31-gpio", .data = &imx31_gpio_hwdata }, + { .compatible = "fsl,imx35-gpio", .data = &imx35_gpio_hwdata }, + { .compatible = "fsl,imx7d-gpio", .data = &imx35_gpio_hwdata }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, mxc_gpio_dt_ids); + +/* + * 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; + unsigned long flags; + u32 bit, val; + u32 gpio_idx = d->hwirq; + 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 = port->gc.get(&port->gc, gpio_idx); + if (val) { + edge = GPIO_INT_LOW_LEV; + pr_debug("mxc: set GPIO %d to low trigger\n", gpio_idx); + } else { + edge = GPIO_INT_HIGH_LEV; + pr_debug("mxc: set GPIO %d to high trigger\n", gpio_idx); + } + 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; + } + + raw_spin_lock_irqsave(&port->gc.bgpio_lock, flags); + + 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); + + raw_spin_unlock_irqrestore(&port->gc.bgpio_lock, flags); + + return port->gc.direction_input(&port->gc, gpio_idx); +} + +static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio) +{ + void __iomem *reg = port->base; + unsigned long flags; + u32 bit, val; + int edge; + + raw_spin_lock_irqsave(&port->gc.bgpio_lock, flags); + + 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); + goto unlock; + } + writel(val | (edge << (bit << 1)), reg); + +unlock: + raw_spin_unlock_irqrestore(&port->gc.bgpio_lock, flags); +} + +/* 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_domain_irq(port->domain, irqoffset); + + irq_stat &= ~(1 << irqoffset); + } +} + +/* MX1 and MX3 has one interrupt *per* gpio port */ +static void mx3_gpio_irq_handler(struct irq_desc *desc) +{ + u32 irq_stat; + struct mxc_gpio_port *port = irq_desc_get_handler_data(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); + + 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(struct irq_desc *desc) +{ + u32 irq_msk, irq_stat; + struct mxc_gpio_port *port; + struct irq_chip *chip = irq_desc_get_chip(desc); + + 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; + int ret; + + if (enable) { + if (port->irq_high && (gpio_idx >= 16)) + ret = enable_irq_wake(port->irq_high); + else + ret = enable_irq_wake(port->irq); + } else { + if (port->irq_high && (gpio_idx >= 16)) + ret = disable_irq_wake(port->irq_high); + else + ret = disable_irq_wake(port->irq); + } + + return ret; +} + +static int mxc_gpio_init_gc(struct mxc_gpio_port *port, int irq_base) +{ + struct irq_chip_generic *gc; + struct irq_chip_type *ct; + int rv; + + gc = devm_irq_alloc_generic_chip(port->dev, "gpio-mxc", 1, irq_base, + port->base, handle_level_irq); + if (!gc) + return -ENOMEM; + 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->chip.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND; + ct->regs.ack = GPIO_ISR; + ct->regs.mask = GPIO_IMR; + + rv = devm_irq_setup_generic_chip(port->dev, gc, IRQ_MSK(32), + IRQ_GC_INIT_NESTED_LOCK, + IRQ_NOREQUEST, 0); + + return rv; +} + +static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct mxc_gpio_port *port = gpiochip_get_data(gc); + + 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; + int irq_count; + int irq_base; + int err; + + port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL); + if (!port) + return -ENOMEM; + + port->dev = &pdev->dev; + + port->hwdata = device_get_match_data(&pdev->dev); + + port->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(port->base)) + return PTR_ERR(port->base); + + irq_count = platform_irq_count(pdev); + if (irq_count < 0) + return irq_count; + + if (irq_count > 1) { + port->irq_high = platform_get_irq(pdev, 1); + if (port->irq_high < 0) + port->irq_high = 0; + } + + port->irq = platform_get_irq(pdev, 0); + if (port->irq < 0) + return port->irq; + + /* the controller clock is optional */ + port->clk = devm_clk_get_optional(&pdev->dev, NULL); + if (IS_ERR(port->clk)) + return PTR_ERR(port->clk); + + err = clk_prepare_enable(port->clk); + if (err) { + dev_err(&pdev->dev, "Unable to enable clock.\n"); + return err; + } + + if (of_device_is_compatible(np, "fsl,imx7d-gpio")) + port->power_off = true; + + /* disable the interrupt and clear the status */ + writel(0, port->base + GPIO_IMR); + writel(~0, port->base + GPIO_ISR); + + if (of_device_is_compatible(np, "fsl,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_and_data(port->irq, + mx3_gpio_irq_handler, port); + if (port->irq_high > 0) + /* setup handler for GPIO 16 to 31 */ + irq_set_chained_handler_and_data(port->irq_high, + mx3_gpio_irq_handler, + port); + } + + err = bgpio_init(&port->gc, &pdev->dev, 4, + port->base + GPIO_PSR, + port->base + GPIO_DR, NULL, + port->base + GPIO_GDIR, NULL, + BGPIOF_READ_OUTPUT_REG_SET); + if (err) + goto out_bgio; + + port->gc.request = gpiochip_generic_request; + port->gc.free = gpiochip_generic_free; + port->gc.to_irq = mxc_gpio_to_irq; + port->gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 : + pdev->id * 32; + + err = devm_gpiochip_add_data(&pdev->dev, &port->gc, port); + if (err) + goto out_bgio; + + irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, 32, numa_node_id()); + if (irq_base < 0) { + err = irq_base; + goto out_bgio; + } + + port->domain = irq_domain_add_legacy(np, 32, irq_base, 0, + &irq_domain_simple_ops, NULL); + if (!port->domain) { + err = -ENODEV; + goto out_bgio; + } + + /* gpio-mxc can be a generic irq chip */ + err = mxc_gpio_init_gc(port, irq_base); + if (err < 0) + goto out_irqdomain_remove; + + list_add_tail(&port->node, &mxc_gpio_ports); + + platform_set_drvdata(pdev, port); + + return 0; + +out_irqdomain_remove: + irq_domain_remove(port->domain); +out_bgio: + clk_disable_unprepare(port->clk); + dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err); + return err; +} + +static void mxc_gpio_save_regs(struct mxc_gpio_port *port) +{ + if (!port->power_off) + return; + + port->gpio_saved_reg.icr1 = readl(port->base + GPIO_ICR1); + port->gpio_saved_reg.icr2 = readl(port->base + GPIO_ICR2); + port->gpio_saved_reg.imr = readl(port->base + GPIO_IMR); + port->gpio_saved_reg.gdir = readl(port->base + GPIO_GDIR); + port->gpio_saved_reg.edge_sel = readl(port->base + GPIO_EDGE_SEL); + port->gpio_saved_reg.dr = readl(port->base + GPIO_DR); +} + +static void mxc_gpio_restore_regs(struct mxc_gpio_port *port) +{ + if (!port->power_off) + return; + + writel(port->gpio_saved_reg.icr1, port->base + GPIO_ICR1); + writel(port->gpio_saved_reg.icr2, port->base + GPIO_ICR2); + writel(port->gpio_saved_reg.imr, port->base + GPIO_IMR); + writel(port->gpio_saved_reg.gdir, port->base + GPIO_GDIR); + writel(port->gpio_saved_reg.edge_sel, port->base + GPIO_EDGE_SEL); + writel(port->gpio_saved_reg.dr, port->base + GPIO_DR); +} + +static int mxc_gpio_syscore_suspend(void) +{ + struct mxc_gpio_port *port; + + /* walk through all ports */ + list_for_each_entry(port, &mxc_gpio_ports, node) { + mxc_gpio_save_regs(port); + clk_disable_unprepare(port->clk); + } + + return 0; +} + +static void mxc_gpio_syscore_resume(void) +{ + struct mxc_gpio_port *port; + int ret; + + /* walk through all ports */ + list_for_each_entry(port, &mxc_gpio_ports, node) { + ret = clk_prepare_enable(port->clk); + if (ret) { + pr_err("mxc: failed to enable gpio clock %d\n", ret); + return; + } + mxc_gpio_restore_regs(port); + } +} + +static struct syscore_ops mxc_gpio_syscore_ops = { + .suspend = mxc_gpio_syscore_suspend, + .resume = mxc_gpio_syscore_resume, +}; + +static struct platform_driver mxc_gpio_driver = { + .driver = { + .name = "gpio-mxc", + .of_match_table = mxc_gpio_dt_ids, + .suppress_bind_attrs = true, + }, + .probe = mxc_gpio_probe, +}; + +static int __init gpio_mxc_init(void) +{ + register_syscore_ops(&mxc_gpio_syscore_ops); + + return platform_driver_register(&mxc_gpio_driver); +} +subsys_initcall(gpio_mxc_init); + +MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>"); +MODULE_DESCRIPTION("i.MX GPIO Driver"); +MODULE_LICENSE("GPL"); |