[PATCH v4 1/4] staging: greybus: gpio: switch GPIO portions to use GPIOLIB_IRQCHIP

Nishad Kamdar
2018-12-22T17:43:30Z

Convert the GPIO driver to use the GPIO irqchip library
GPIOLIB_IRQCHIP instead of reimplementing the same.

Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
---
Changes in v4:
- Remove changes related to conversion to gpiochip_get_data() to
include it as a new patch.
- Remove the 'struct irq_chip' field from 'struct gb_gpio_controller'
as struct gpio_chip will have an irqchip whenever
CONFIG_GPIOLIB_IRQCHIP is selected.
- Update the TODO file as per the changes.
Changes in v3:
- Combine patches as into a patch series.
Changes in v2:
- Retained irq.h and irqdomain.h headers.
- Dropped function gb_gpio_irqchip_add() and
called gpiochip_irqchip_add() from probe().
- Referred https://lkml.kernel.org/r/1476054589-28422-1-git-send-email-linus.walleij@linaro.org.
---
drivers/staging/greybus/Kconfig | 1 +
drivers/staging/greybus/TODO | 2 -
drivers/staging/greybus/gpio.c | 159 +++-----------------------------
3 files changed, 12 insertions(+), 150 deletions(-)

diff --git a/drivers/staging/greybus/Kconfig b/drivers/staging/greybus/Kconfig
index ab096bcef98c..b571e4e8060b 100644
--- a/drivers/staging/greybus/Kconfig
+++ b/drivers/staging/greybus/Kconfig
@@ -148,6 +148,7 @@ if GREYBUS_BRIDGED_PHY
config GREYBUS_GPIO
tristate "Greybus GPIO Bridged PHY driver"
depends on GPIOLIB
+ select GPIOLIB_IRQCHIP
---help---
Select this option if you have a device that follows the
Greybus GPIO Bridged PHY Class specification.
diff --git a/drivers/staging/greybus/TODO b/drivers/staging/greybus/TODO
index 3b90a5711998..31f1f2cb401c 100644
--- a/drivers/staging/greybus/TODO
+++ b/drivers/staging/greybus/TODO
@@ -1,5 +1,3 @@
* Convert all uses of the old GPIO API from <linux/gpio.h> to the
GPIO descriptor API in <linux/gpio/consumer.h> and look up GPIO
lines from device tree or ACPI.
-* Convert the GPIO driver to use the GPIO irqchip library
- GPIOLIB_IRQCHIP instead of reimplementing the same.
diff --git a/drivers/staging/greybus/gpio.c b/drivers/staging/greybus/gpio.c
index e110681e6f86..1af291aa1b6e 100644
--- a/drivers/staging/greybus/gpio.c
+++ b/drivers/staging/greybus/gpio.c
@@ -9,9 +9,9 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
-#include <linux/gpio.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
+#include <linux/gpio/driver.h>
#include <linux/mutex.h>

#include "greybus.h"
@@ -38,12 +38,6 @@ struct gb_gpio_controller {
struct gb_gpio_line *lines;

struct gpio_chip chip;
- struct irq_chip irqc;
- struct irq_chip *irqchip;
- struct irq_domain *irqdomain;
- unsigned int irq_base;
- irq_flow_handler_t irq_handler;
- unsigned int irq_default_type;
struct mutex irq_lock;
};
#define gpio_chip_to_gb_gpio_controller(chip) \
@@ -391,7 +385,7 @@ static int gb_gpio_request_handler(struct gb_operation *op)
return -EINVAL;
}

- irq = irq_find_mapping(ggc->irqdomain, event->which);
+ irq = irq_find_mapping(ggc->chip.irq.domain, event->which);
if (!irq) {
dev_err(dev, "failed to find IRQ\n");
return -EINVAL;
@@ -506,135 +500,6 @@ static int gb_gpio_controller_setup(struct gb_gpio_controller *ggc)
return ret;
}

-/**
- * gb_gpio_irq_map() - maps an IRQ into a GB gpio irqchip
- * @d: the irqdomain used by this irqchip
- * @irq: the global irq number used by this GB gpio irqchip irq
- * @hwirq: the local IRQ/GPIO line offset on this GB gpio
- *
- * This function will set up the mapping for a certain IRQ line on a
- * GB gpio by assigning the GB gpio as chip data, and using the irqchip
- * stored inside the GB gpio.
- */
-static int gb_gpio_irq_map(struct irq_domain *domain, unsigned int irq,
- irq_hw_number_t hwirq)
-{
- struct gpio_chip *chip = domain->host_data;
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
-
- irq_set_chip_data(irq, ggc);
- irq_set_chip_and_handler(irq, ggc->irqchip, ggc->irq_handler);
- irq_set_noprobe(irq);
- /*
- * No set-up of the hardware will happen if IRQ_TYPE_NONE
- * is passed as default type.
- */
- if (ggc->irq_default_type != IRQ_TYPE_NONE)
- irq_set_irq_type(irq, ggc->irq_default_type);
-
- return 0;
-}
-
-static void gb_gpio_irq_unmap(struct irq_domain *d, unsigned int irq)
-{
- irq_set_chip_and_handler(irq, NULL, NULL);
- irq_set_chip_data(irq, NULL);
-}
-
-static const struct irq_domain_ops gb_gpio_domain_ops = {
- .map = gb_gpio_irq_map,
- .unmap = gb_gpio_irq_unmap,
-};
-
-/**
- * gb_gpio_irqchip_remove() - removes an irqchip added to a gb_gpio_controller
- * @ggc: the gb_gpio_controller to remove the irqchip from
- *
- * This is called only from gb_gpio_remove()
- */
-static void gb_gpio_irqchip_remove(struct gb_gpio_controller *ggc)
-{
- unsigned int offset;
-
- /* Remove all IRQ mappings and delete the domain */
- if (ggc->irqdomain) {
- for (offset = 0; offset < (ggc->line_max + 1); offset++)
- irq_dispose_mapping(irq_find_mapping(ggc->irqdomain,
- offset));
- irq_domain_remove(ggc->irqdomain);
- }
-
- if (ggc->irqchip)
- ggc->irqchip = NULL;
-}
-
-/**
- * gb_gpio_irqchip_add() - adds an irqchip to a gpio chip
- * @chip: the gpio chip to add the irqchip to
- * @irqchip: the irqchip to add to the adapter
- * @first_irq: if not dynamically assigned, the base (first) IRQ to
- * allocate gpio irqs from
- * @handler: the irq handler to use (often a predefined irq core function)
- * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
- * to have the core avoid setting up any default type in the hardware.
- *
- * This function closely associates a certain irqchip with a certain
- * gpio chip, providing an irq domain to translate the local IRQs to
- * global irqs, and making sure that the gpio chip
- * is passed as chip data to all related functions. Driver callbacks
- * need to use container_of() to get their local state containers back
- * from the gpio chip passed as chip data. An irqdomain will be stored
- * in the gpio chip that shall be used by the driver to handle IRQ number
- * translation. The gpio chip will need to be initialized and registered
- * before calling this function.
- */
-static int gb_gpio_irqchip_add(struct gpio_chip *chip,
- struct irq_chip *irqchip,
- unsigned int first_irq,
- irq_flow_handler_t handler,
- unsigned int type)
-{
- struct gb_gpio_controller *ggc;
- unsigned int offset;
- unsigned int irq_base;
-
- if (!chip || !irqchip)
- return -EINVAL;
-
- ggc = gpio_chip_to_gb_gpio_controller(chip);
-
- ggc->irqchip = irqchip;
- ggc->irq_handler = handler;
- ggc->irq_default_type = type;
- ggc->irqdomain = irq_domain_add_simple(NULL,
- ggc->line_max + 1, first_irq,
- &gb_gpio_domain_ops, chip);
- if (!ggc->irqdomain) {
- ggc->irqchip = NULL;
- return -EINVAL;
- }
-
- /*
- * Prepare the mapping since the irqchip shall be orthogonal to
- * any gpio calls. If the first_irq was zero, this is
- * necessary to allocate descriptors for all IRQs.
- */
- for (offset = 0; offset < (ggc->line_max + 1); offset++) {
- irq_base = irq_create_mapping(ggc->irqdomain, offset);
- if (offset == 0)
- ggc->irq_base = irq_base;
- }
-
- return 0;
-}
-
-static int gb_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
-{
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
-
- return irq_find_mapping(ggc->irqdomain, offset);
-}
-
static int gb_gpio_probe(struct gbphy_device *gbphy_dev,
const struct gbphy_device_id *id)
{
@@ -670,7 +535,7 @@ static int gb_gpio_probe(struct gbphy_device *gbphy_dev,
if (ret)
goto exit_connection_disable;

- irqc = &ggc->irqc;
+ irqc = ggc->chip.irq.chip;
irqc->irq_mask = gb_gpio_irq_mask;
irqc->irq_unmask = gb_gpio_irq_unmask;
irqc->irq_set_type = gb_gpio_irq_set_type;
@@ -694,7 +559,6 @@ static int gb_gpio_probe(struct gbphy_device *gbphy_dev,
gpio->get = gb_gpio_get;
gpio->set = gb_gpio_set;
gpio->set_config = gb_gpio_set_config;
- gpio->to_irq = gb_gpio_to_irq;
gpio->base = -1; /* Allocate base dynamically */
gpio->ngpio = ggc->line_max + 1;
gpio->can_sleep = true;
@@ -703,24 +567,24 @@ static int gb_gpio_probe(struct gbphy_device *gbphy_dev,
if (ret)
goto exit_line_free;

- ret = gb_gpio_irqchip_add(gpio, irqc, 0,
- handle_level_irq, IRQ_TYPE_NONE);
+ ret = gpiochip_add(gpio);
if (ret) {
- dev_err(&gbphy_dev->dev, "failed to add irq chip: %d\n", ret);
+ dev_err(&gbphy_dev->dev, "failed to add gpio chip: %d\n", ret);
goto exit_line_free;
}

- ret = gpiochip_add(gpio);
+ ret = gpiochip_irqchip_add(gpio, irqc, 0, handle_level_irq,
+ IRQ_TYPE_NONE);
if (ret) {
- dev_err(&gbphy_dev->dev, "failed to add gpio chip: %d\n", ret);
- goto exit_gpio_irqchip_remove;
+ dev_err(&gbphy_dev->dev, "failed to add irq chip: %d\n", ret);
+ goto exit_gpiochip_remove;
}

gbphy_runtime_put_autosuspend(gbphy_dev);
return 0;

-exit_gpio_irqchip_remove:
- gb_gpio_irqchip_remove(ggc);
+exit_gpiochip_remove:
+ gpiochip_remove(gpio);
exit_line_free:
kfree(ggc->lines);
exit_connection_disable:
@@ -744,7 +608,6 @@ static void gb_gpio_remove(struct gbphy_device *gbphy_dev)

gb_connection_disable_rx(connection);
gpiochip_remove(&ggc->chip);
- gb_gpio_irqchip_remove(ggc);
gb_connection_disable(connection);
gb_connection_destroy(connection);
kfree(ggc->lines);
--
2.17.1