[PATCH v2 8/9] gpio: mockup: use the generic 'gpio-line-names' property

From: Bartosz Golaszewski
Date: Mon Sep 28 2020 - 06:42:18 EST


From: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>

GPIO line names are currently created by the driver from the chip label.
We'll want to support custom formats for line names (for instance: to
name all lines the same) for user-space tests so create them in the
module init function and pass them to the driver using the standard
'gpio-line-names' property.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
---
drivers/gpio/gpio-mockup.c | 70 +++++++++++++++++++++-----------------
1 file changed, 38 insertions(+), 32 deletions(-)

diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
index 5b2686f9e07d..47b7de6d5ab1 100644
--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -19,6 +19,7 @@
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/slab.h>
+#include <linux/string_helpers.h>
#include <linux/uaccess.h>

#include "gpiolib.h"
@@ -374,29 +375,6 @@ static void gpio_mockup_debugfs_setup(struct device *dev,
}
}

-static int gpio_mockup_name_lines(struct device *dev,
- struct gpio_mockup_chip *chip)
-{
- struct gpio_chip *gc = &chip->gc;
- char **names;
- int i;
-
- names = devm_kcalloc(dev, gc->ngpio, sizeof(char *), GFP_KERNEL);
- if (!names)
- return -ENOMEM;
-
- for (i = 0; i < gc->ngpio; i++) {
- names[i] = devm_kasprintf(dev, GFP_KERNEL,
- "%s-%d", gc->label, i);
- if (!names[i])
- return -ENOMEM;
- }
-
- gc->names = (const char *const *)names;
-
- return 0;
-}
-
static void gpio_mockup_dispose_mappings(void *data)
{
struct gpio_mockup_chip *chip = data;
@@ -464,12 +442,6 @@ static int gpio_mockup_probe(struct platform_device *pdev)
for (i = 0; i < gc->ngpio; i++)
chip->lines[i].dir = GPIO_LINE_DIRECTION_IN;

- if (device_property_read_bool(dev, "named-gpio-lines")) {
- rv = gpio_mockup_name_lines(dev, chip);
- if (rv)
- return rv;
- }
-
chip->irq_sim_domain = devm_irq_domain_create_sim(dev, NULL,
gc->ngpio);
if (IS_ERR(chip->irq_sim_domain))
@@ -510,6 +482,27 @@ static void gpio_mockup_unregister_pdevs(void)
}
}

+static __init char **gpio_mockup_make_line_names(const char *label,
+ unsigned int num_lines)
+{
+ unsigned int i;
+ char **names;
+
+ names = kcalloc(num_lines + 1, sizeof(char *), GFP_KERNEL);
+ if (!names)
+ return NULL;
+
+ for (i = 0; i < num_lines; i++) {
+ names[i] = kasprintf(GFP_KERNEL, "%s-%u", label, i);
+ if (!names[i]) {
+ kfree_strarray(names, i);
+ return NULL;
+ }
+ }
+
+ return names;
+}
+
static int __init gpio_mockup_init(void)
{
struct property_entry properties[GPIO_MOCKUP_MAX_PROP];
@@ -517,6 +510,7 @@ static int __init gpio_mockup_init(void)
struct platform_device_info pdevinfo;
struct platform_device *pdev;
char chip_label[32];
+ char **line_names;
u16 ngpio;

if ((gpio_mockup_num_ranges < 2) ||
@@ -549,6 +543,7 @@ static int __init gpio_mockup_init(void)
memset(properties, 0, sizeof(properties));
memset(&pdevinfo, 0, sizeof(pdevinfo));
prop = 0;
+ line_names = NULL;

snprintf(chip_label, sizeof(chip_label),
"gpio-mockup-%c", i + 'A');
@@ -564,15 +559,26 @@ static int __init gpio_mockup_init(void)
: gpio_mockup_range_ngpio(i) - base;
properties[prop++] = PROPERTY_ENTRY_U16("nr-gpios", ngpio);

- if (gpio_mockup_named_lines)
- properties[prop++] = PROPERTY_ENTRY_BOOL(
- "named-gpio-lines");
+ if (gpio_mockup_named_lines) {
+ line_names = gpio_mockup_make_line_names(chip_label,
+ ngpio);
+ if (!line_names) {
+ platform_driver_unregister(&gpio_mockup_driver);
+ gpio_mockup_unregister_pdevs();
+ return -ENOMEM;
+ }
+
+ properties[prop++] = PROPERTY_ENTRY_STRING_ARRAY_LEN(
+ "gpio-line-names",
+ line_names, ngpio);
+ }

pdevinfo.name = "gpio-mockup";
pdevinfo.id = i;
pdevinfo.properties = properties;

pdev = platform_device_register_full(&pdevinfo);
+ kfree_strarray(line_names, ngpio);
if (IS_ERR(pdev)) {
pr_err("error registering device");
platform_driver_unregister(&gpio_mockup_driver);
--
2.26.1