Re: [PATCH v2] RFC: staging: greybus: shape up greybus GPIO

From: Rui Miguel Silva
Date: Mon Oct 10 2016 - 10:20:02 EST


Hi Linus,
On Mon, Oct 10, 2016 at 10:39:32AM +0200, Linus Walleij wrote:
Greybus GPIO seems to reimplement the already existing generic
gpiolib irqchip. Also use gpiochip_get_data(). Also use
devm_gpiochip_add_data().

Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Cc: Axel Haslam <haslam_axel@xxxxxxxxxxxxxx>
Cc: Johan Hovold <johan@xxxxxxxxxxxxxxxxxxxx>
Cc: Sandeep Patil <patil_sandeep@xxxxxxxxxxxxxx>
Cc: Rui Miguel Silva <rui.silva@xxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

This was a necessary change for recent kernels.

Looks good to me. Thanks.
Reviewed-by: Rui Miguel Silva <rmfrfs@xxxxxxxxx>

---
ChangeLog v1->v2:
- Add the hunk adding select GPIOLIB_IRQCHIP to Kconfig,
sorry for sending patches too late in the night.

Greybus folks: please look at this. I expect something like this
to be applied before migrating from staging, I can't test it
obviously.
---
drivers/staging/greybus/Kconfig | 1 +
drivers/staging/greybus/gpio.c | 183 +++++-----------------------------------
2 files changed, 24 insertions(+), 160 deletions(-)

diff --git a/drivers/staging/greybus/Kconfig b/drivers/staging/greybus/Kconfig
index 50de2d72dde0..b05a8f4657e3 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/gpio.c b/drivers/staging/greybus/gpio.c
index 5e06e4229e42..07ccd819ee1c 100644
--- a/drivers/staging/greybus/gpio.c
+++ b/drivers/staging/greybus/gpio.c
@@ -10,7 +10,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
-#include <linux/gpio.h>
+#include <linux/gpio/driver.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/mutex.h>
@@ -41,14 +41,8 @@ struct gb_gpio_controller {
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) \
- container_of(chip, struct gb_gpio_controller, chip)
#define irq_data_to_gpio_chip(d) (d->domain->host_data)

static int gb_gpio_line_count_operation(struct gb_gpio_controller *ggc)
@@ -277,7 +271,7 @@ static void _gb_gpio_irq_set_type(struct gb_gpio_controller *ggc,
static void gb_gpio_irq_mask(struct irq_data *d)
{
struct gpio_chip *chip = irq_data_to_gpio_chip(d);
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);
struct gb_gpio_line *line = &ggc->lines[d->hwirq];

line->masked = true;
@@ -287,7 +281,7 @@ static void gb_gpio_irq_mask(struct irq_data *d)
static void gb_gpio_irq_unmask(struct irq_data *d)
{
struct gpio_chip *chip = irq_data_to_gpio_chip(d);
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);
struct gb_gpio_line *line = &ggc->lines[d->hwirq];

line->masked = false;
@@ -297,7 +291,7 @@ static void gb_gpio_irq_unmask(struct irq_data *d)
static int gb_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *chip = irq_data_to_gpio_chip(d);
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);
struct gb_gpio_line *line = &ggc->lines[d->hwirq];
struct device *dev = &ggc->gbphy_dev->dev;
u8 irq_type;
@@ -335,7 +329,7 @@ static int gb_gpio_irq_set_type(struct irq_data *d, unsigned int type)
static void gb_gpio_irq_bus_lock(struct irq_data *d)
{
struct gpio_chip *chip = irq_data_to_gpio_chip(d);
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);

mutex_lock(&ggc->irq_lock);
}
@@ -343,7 +337,7 @@ static void gb_gpio_irq_bus_lock(struct irq_data *d)
static void gb_gpio_irq_bus_sync_unlock(struct irq_data *d)
{
struct gpio_chip *chip = irq_data_to_gpio_chip(d);
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);
struct gb_gpio_line *line = &ggc->lines[d->hwirq];

if (line->irq_type_pending) {
@@ -392,7 +386,7 @@ 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.irqdomain, event->which);
if (!irq) {
dev_err(dev, "failed to find IRQ\n");
return -EINVAL;
@@ -412,21 +406,21 @@ static int gb_gpio_request_handler(struct gb_operation *op)

static int gb_gpio_request(struct gpio_chip *chip, unsigned offset)
{
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);

return gb_gpio_activate_operation(ggc, (u8)offset);
}

static void gb_gpio_free(struct gpio_chip *chip, unsigned offset)
{
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);

gb_gpio_deactivate_operation(ggc, (u8)offset);
}

static int gb_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
{
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);
u8 which;
int ret;

@@ -440,7 +434,7 @@ static int gb_gpio_get_direction(struct gpio_chip *chip, unsigned offset)

static int gb_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);

return gb_gpio_direction_in_operation(ggc, (u8)offset);
}
@@ -448,14 +442,14 @@ static int gb_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
static int gb_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
int value)
{
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);

return gb_gpio_direction_out_operation(ggc, (u8)offset, !!value);
}

static int gb_gpio_get(struct gpio_chip *chip, unsigned offset)
{
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);
u8 which;
int ret;

@@ -469,7 +463,7 @@ static int gb_gpio_get(struct gpio_chip *chip, unsigned offset)

static void gb_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);

gb_gpio_set_value_operation(ggc, (u8)offset, !!value);
}
@@ -477,7 +471,7 @@ static void gb_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
static int gb_gpio_set_debounce(struct gpio_chip *chip, unsigned offset,
unsigned debounce)
{
- struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip);
+ struct gb_gpio_controller *ggc = gpiochip_get_data(chip);
u16 usec;

if (debounce > U16_MAX)
@@ -504,134 +498,6 @@ 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 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 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)
{
@@ -690,7 +556,6 @@ static int gb_gpio_probe(struct gbphy_device *gbphy_dev,
gpio->get = gb_gpio_get;
gpio->set = gb_gpio_set;
gpio->set_debounce = gb_gpio_set_debounce;
- gpio->to_irq = gb_gpio_to_irq;
gpio->base = -1; /* Allocate base dynamically */
gpio->ngpio = ggc->line_max + 1;
gpio->can_sleep = true;
@@ -699,26 +564,26 @@ 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 = devm_gpiochip_add_data(&connection->bundle->dev,
+ gpio, ggc);
if (ret) {
dev_err(&connection->bundle->dev,
- "failed to add irq chip: %d\n", ret);
+ "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(&connection->bundle->dev,
- "failed to add gpio chip: %d\n", ret);
- goto exit_gpio_irqchip_remove;
+ "failed to add gpio irqchip: %d\n", ret);
+ goto exit_line_free;
}

gbphy_runtime_put_autosuspend(gbphy_dev);
return 0;

-exit_gpio_irqchip_remove:
- gb_gpio_irqchip_remove(ggc);
exit_line_free:
kfree(ggc->lines);
exit_connection_disable:
@@ -741,8 +606,6 @@ static void gb_gpio_remove(struct gbphy_device *gbphy_dev)
gbphy_runtime_get_noresume(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);
--
2.7.4

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