[RFC PATCH] GPIO/ACPI: DesignWare: Add GPIO-signaled ACPI events support for power button

From: qiujiang
Date: Fri Feb 05 2016 - 01:20:10 EST

This patch modifies the DesignWare GPIO controller driver to
support the GPIO-signaled ACPI Events. This is used for power
button function on ARM server.

To make it work, the _AEI and _EVT object must be defined in
the corresponding GPIO driver's dsdt table in UEFI. At the same
time, ACPI daemon component is also necessary.

Signed-off-by: qiujiang <qiujiang@xxxxxxxxxx>
---
drivers/gpio/gpio-dwapb.c | 75 ++++++++++++++++++++------------
include/linux/platform_data/gpio-dwapb.h | 2 +-
2 files changed, 49 insertions(+), 28 deletions(-)

diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
index fcd5b0a..bfed2e9 100644
--- a/drivers/gpio/gpio-dwapb.c
+++ b/drivers/gpio/gpio-dwapb.c
@@ -23,6 +23,11 @@
#include <linux/spinlock.h>
#include <linux/platform_data/gpio-dwapb.h>
#include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/gpio.h>
+
+#include "gpiolib.h"
+

#define GPIO_SWPORTA_DR 0x00
#define GPIO_SWPORTA_DDR 0x04
@@ -296,14 +301,14 @@ static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
struct dwapb_port_property *pp)
{
struct gpio_chip *gc = &port->bgc.gc;
- struct device_node *node = pp->node;
+ struct fwnode_handle *fwnode = pp->fwnode;
struct irq_chip_generic *irq_gc = NULL;
unsigned int hwirq, ngpio = gc->ngpio;
struct irq_chip_type *ct;
int err, i;

- gpio->domain = irq_domain_add_linear(node, ngpio,
- &irq_generic_chip_ops, gpio);
+ gpio->domain = irq_domain_create_linear(fwnode,
+ ngpio, &irq_generic_chip_ops, gpio);
if (!gpio->domain)
return;

@@ -421,7 +426,7 @@ static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
}

#ifdef CONFIG_OF_GPIO
- port->bgc.gc.of_node = pp->node;
+ port->bgc.gc.of_node = to_of_node(pp->fwnode);
#endif
port->bgc.gc.ngpio = pp->ngpio;
port->bgc.gc.base = pp->gpio_base;
@@ -440,6 +445,10 @@ static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
else
port->is_registered = true;

+ /* Add GPIO-signaled ACPI event support */
+ if (pp->irq)
+ acpi_gpiochip_request_interrupts(&(port->bgc.gc));
+
return err;
}

@@ -453,19 +462,15 @@ static void dwapb_gpio_unregister(struct dwapb_gpio *gpio)
}

static struct dwapb_platform_data *
-dwapb_gpio_get_pdata_of(struct device *dev)
+dwapb_gpio_get_pdata(struct device *dev)
{
- struct device_node *node, *port_np;
+ struct fwnode_handle *fwnode;
struct dwapb_platform_data *pdata;
struct dwapb_port_property *pp;
int nports;
int i;

- node = dev->of_node;
- if (!IS_ENABLED(CONFIG_OF_GPIO) || !node)
- return ERR_PTR(-ENODEV);
-
- nports = of_get_child_count(node);
+ nports = device_get_child_node_count(dev);
if (nports == 0)
return ERR_PTR(-ENODEV);

@@ -480,21 +485,19 @@ dwapb_gpio_get_pdata_of(struct device *dev)
pdata->nports = nports;

i = 0;
- for_each_child_of_node(node, port_np) {
- pp = &pdata->properties[i++];
- pp->node = port_np;
+ device_for_each_child_node(dev, fwnode) {
+ pp = &pdata->properties[i];
+ pp->fwnode = fwnode;

- if (of_property_read_u32(port_np, "reg", &pp->idx) ||
+ if (fwnode_property_read_u32(fwnode, "reg", &pp->idx) ||
pp->idx >= DWAPB_MAX_PORTS) {
- dev_err(dev, "missing/invalid port index for %s\n",
- port_np->full_name);
+ dev_err(dev, "missing/invalid port index\n");
return ERR_PTR(-EINVAL);
}

- if (of_property_read_u32(port_np, "snps,nr-gpios",
+ if (fwnode_property_read_u32(fwnode, "snps,nr-gpios",
&pp->ngpio)) {
- dev_info(dev, "failed to get number of gpios for %s\n",
- port_np->full_name);
+ dev_info(dev, "failed to get number of gpios\n");
pp->ngpio = 32;
}

@@ -502,18 +505,27 @@ dwapb_gpio_get_pdata_of(struct device *dev)
* Only port A can provide interrupts in all configurations of
* the IP.
*/
- if (pp->idx == 0 &&
- of_property_read_bool(port_np, "interrupt-controller")) {
- pp->irq = irq_of_parse_and_map(port_np, 0);
+ if (dev->of_node && pp->idx == 0 &&
+ of_property_read_bool(to_of_node(fwnode),
+ "interrupt-controller")) {
+ pp->irq = irq_of_parse_and_map(to_of_node(fwnode), 0);
if (!pp->irq) {
- dev_warn(dev, "no irq for bank %s\n",
- port_np->full_name);
+ dev_warn(dev, "no irq for bank %s\n",
+ to_of_node(fwnode)->full_name);
}
}

+ if (ACPI_COMPANION(dev) && pp->idx == 0)
+ pp->irq = platform_get_irq(to_platform_device(dev), 0);
+
pp->irq_shared = false;
pp->gpio_base = -1;
- pp->name = port_np->full_name;
+
+ if (dev->of_node)
+ pp->name = to_of_node(fwnode)->full_name;
+
+ if (ACPI_COMPANION(dev))
+ pp->name = acpi_dev_name(to_acpi_device_node(fwnode));
}

return pdata;
@@ -529,7 +541,7 @@ static int dwapb_gpio_probe(struct platform_device *pdev)
struct dwapb_platform_data *pdata = dev_get_platdata(dev);

if (!pdata) {
- pdata = dwapb_gpio_get_pdata_of(dev);
+ pdata = dwapb_gpio_get_pdata(dev);
if (IS_ERR(pdata))
return PTR_ERR(pdata);
}
@@ -559,6 +571,7 @@ static int dwapb_gpio_probe(struct platform_device *pdev)
if (err)
goto out_unregister;
}
+
platform_set_drvdata(pdev, gpio);

return 0;
@@ -586,6 +599,13 @@ static const struct of_device_id dwapb_of_match[] = {
};
MODULE_DEVICE_TABLE(of, dwapb_of_match);

+static const struct acpi_device_id dwapb_acpi_match[] = {
+ {"HISI0181", 0},
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, dwapb_acpi_match);
+
+
#ifdef CONFIG_PM_SLEEP
static int dwapb_gpio_suspend(struct device *dev)
{
@@ -680,6 +700,7 @@ static struct platform_driver dwapb_gpio_driver = {
.name = "gpio-dwapb",
.pm = &dwapb_gpio_pm_ops,
.of_match_table = of_match_ptr(dwapb_of_match),
+ .acpi_match_table = ACPI_PTR(dwapb_acpi_match),
},
.probe = dwapb_gpio_probe,
.remove = dwapb_gpio_remove,
diff --git a/include/linux/platform_data/gpio-dwapb.h b/include/linux/platform_data/gpio-dwapb.h
index 28702c8..c5bd1f2 100644
--- a/include/linux/platform_data/gpio-dwapb.h
+++ b/include/linux/platform_data/gpio-dwapb.h
@@ -15,7 +15,7 @@
#define GPIO_DW_APB_H

struct dwapb_port_property {
- struct device_node *node;
+ struct fwnode_handle *fwnode;
const char *name;
unsigned int idx;
unsigned int ngpio;
--
1.9.1