[PATCH v7 33/47] memory: tegra20-emc: Make driver modular

From: Dmitry Osipenko
Date: Wed Nov 04 2020 - 11:52:20 EST


Add modularization support to the Tegra20 EMC driver, which now can be
compiled as a loadable kernel module.

Acked-by: Thierry Reding <treding@xxxxxxxxxx>
Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
drivers/memory/tegra/Kconfig | 2 +-
drivers/memory/tegra/tegra20-emc.c | 17 ++++++++++++-----
2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/memory/tegra/Kconfig b/drivers/memory/tegra/Kconfig
index b38e5255effe..ff426747cd7d 100644
--- a/drivers/memory/tegra/Kconfig
+++ b/drivers/memory/tegra/Kconfig
@@ -9,7 +9,7 @@ config TEGRA_MC
NVIDIA Tegra SoCs.

config TEGRA20_EMC
- bool "NVIDIA Tegra20 External Memory Controller driver"
+ tristate "NVIDIA Tegra20 External Memory Controller driver"
default y
depends on ARCH_TEGRA_2x_SOC
help
diff --git a/drivers/memory/tegra/tegra20-emc.c b/drivers/memory/tegra/tegra20-emc.c
index c9fe58a724ee..88619e3ec435 100644
--- a/drivers/memory/tegra/tegra20-emc.c
+++ b/drivers/memory/tegra/tegra20-emc.c
@@ -721,6 +721,13 @@ static int tegra_emc_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, emc);
tegra_emc_debugfs_init(emc);

+ /*
+ * Don't allow the kernel module to be unloaded. Unloading adds some
+ * extra complexity which doesn't really worth the effort in a case of
+ * this driver.
+ */
+ try_module_get(THIS_MODULE);
+
return 0;

unset_cb:
@@ -733,6 +740,7 @@ static const struct of_device_id tegra_emc_of_match[] = {
{ .compatible = "nvidia,tegra20-emc", },
{},
};
+MODULE_DEVICE_TABLE(of, tegra_emc_of_match);

static struct platform_driver tegra_emc_driver = {
.probe = tegra_emc_probe,
@@ -742,9 +750,8 @@ static struct platform_driver tegra_emc_driver = {
.suppress_bind_attrs = true,
},
};
+module_platform_driver(tegra_emc_driver);

-static int __init tegra_emc_init(void)
-{
- return platform_driver_register(&tegra_emc_driver);
-}
-subsys_initcall(tegra_emc_init);
+MODULE_AUTHOR("Dmitry Osipenko <digetx@xxxxxxxxx>");
+MODULE_DESCRIPTION("NVIDIA Tegra20 EMC driver");
+MODULE_LICENSE("GPL v2");
--
2.27.0