linux/drivers/gpio/gpio-mxc.c
Anson Huang c19fdaeea0 gpio: mxc: add power management support
GPIO registers could lose context on i.MX7D, when
enter LPSR mode, the whole SoC will be powered off
except LPSR domain, GPIO banks will lose context
in this case, need to restore the context after
resume from LPSR mode.

This patch adds new compatible string for i.MX7D
which supports GPIO power off feature in suspend,
and adds the GPIO save/restore operations in noirq
suspend/resume phase, since GPIO is fundamental
module which could be used by other peripherals'
resume phase.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-29 22:23:17 +02:00

598 lines
15 KiB
C

// 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/platform_device.h>
#include <linux/slab.h>
#include <linux/gpio/driver.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/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_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;
};
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 const 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], },
{ .compatible = "fsl,imx7d-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;
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;
}
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(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;
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 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 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;
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;
port->dev = &pdev->dev;
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);
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(&pdev->dev, NULL);
if (IS_ERR(port->clk))
port->clk = NULL;
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 (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_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;
if (of_property_read_bool(np, "gpio-ranges")) {
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 __maybe_unused mxc_gpio_noirq_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct mxc_gpio_port *port = platform_get_drvdata(pdev);
mxc_gpio_save_regs(port);
clk_disable_unprepare(port->clk);
return 0;
}
static int __maybe_unused mxc_gpio_noirq_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct mxc_gpio_port *port = platform_get_drvdata(pdev);
int ret;
ret = clk_prepare_enable(port->clk);
if (ret)
return ret;
mxc_gpio_restore_regs(port);
return 0;
}
static const struct dev_pm_ops mxc_gpio_dev_pm_ops = {
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mxc_gpio_noirq_suspend, mxc_gpio_noirq_resume)
};
static struct platform_driver mxc_gpio_driver = {
.driver = {
.name = "gpio-mxc",
.of_match_table = mxc_gpio_dt_ids,
.suppress_bind_attrs = true,
.pm = &mxc_gpio_dev_pm_ops,
},
.probe = mxc_gpio_probe,
.id_table = mxc_gpio_devtype,
};
static int __init gpio_mxc_init(void)
{
return platform_driver_register(&mxc_gpio_driver);
}
subsys_initcall(gpio_mxc_init);