On today's platforms the benefit of platform_driver_probe() isn't that
relevant any more. It allows to drop some code after booting (or module
loading) for .probe() and discard the .remove() function completely if
the driver is built-in. This typically saves a few 100k.
The downside of platform_driver_probe() is that the driver cannot be
bound and unbound at runtime which is ancient and also slightly
complicates testing. There are also thoughts to deprecate
platform_driver_probe() because it adds some complexity in the driver
core for little gain. Also many drivers don't use it correctly. This
driver for example misses to mark the driver struct with __refdata which
is needed to suppress a (W=1) modpost warning:
WARNING: modpost: drivers/watchdog/at91sam9_wdt: section mismatch in reference: at91wdt_driver+0x4 (section: .data) -> at91wdt_remove (section: .exit.text)
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
---
drivers/watchdog/at91sam9_wdt.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c
index b111b28acb94..507adb12754d 100644
--- a/drivers/watchdog/at91sam9_wdt.c
+++ b/drivers/watchdog/at91sam9_wdt.c
@@ -324,7 +324,7 @@ static inline int of_at91wdt_init(struct device_node *np, struct at91wdt *wdt)
}
#endif
-static int __init at91wdt_probe(struct platform_device *pdev)
+static int at91wdt_probe(struct platform_device *pdev)
{
int err;
struct at91wdt *wdt;
@@ -372,7 +372,7 @@ static int __init at91wdt_probe(struct platform_device *pdev)
return 0;
}
-static int __exit at91wdt_remove(struct platform_device *pdev)
+static int at91wdt_remove(struct platform_device *pdev)
{
struct at91wdt *wdt = platform_get_drvdata(pdev);
watchdog_unregister_device(&wdt->wdd);
@@ -393,14 +393,14 @@ MODULE_DEVICE_TABLE(of, at91_wdt_dt_ids);
#endif
static struct platform_driver at91wdt_driver = {
- .remove = __exit_p(at91wdt_remove),
+ .probe = at91wdt_probe,
+ .remove = at91wdt_remove,
.driver = {
.name = "at91_wdt",
.of_match_table = of_match_ptr(at91_wdt_dt_ids),
},
};
-
-module_platform_driver_probe(at91wdt_driver, at91wdt_probe);
+module_platform_driver(at91wdt_driver);
MODULE_AUTHOR("Renaud CERRATO <r.cerrato@xxxxxxxxxxxxxxxxxxx>");
MODULE_DESCRIPTION("Watchdog driver for Atmel AT91SAM9x processors");
--
2.42.0
