[PATCH 2/3] mfd: syscon: Remove the platform driver support

Rob Herring (Arm)
2024-12-11T20:57:31Z

The platform driver is dead code. It is not used by DT platforms since
commit bdb0066df96e ("mfd: syscon: Decouple syscon interface from
platform devices") which said:

For non-DT based platforms, this patch keeps syscon platform driver
structure so that syscon can be probed and such non-DT based drivers
can use syscon_regmap_lookup_by_pdev API and access regmap handles.
Once all users of "syscon_regmap_lookup_by_pdev" migrated to DT based,
we can completely remove platform driver of syscon, and keep only helper
functions to get regmap handles.

The last user of syscon_regmap_lookup_by_pdevname() was removed in 2018.
syscon_regmap_lookup_by_pdevname() was then removed in 2019, but that
commit failed to remove the rest of the platform driver.

Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
---
drivers/mfd/syscon.c | 66 ------------------------------------
drivers/mfd/vexpress-sysreg.c | 1 -
include/linux/platform_data/syscon.h | 9 -----
3 files changed, 76 deletions(-)

diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index 72f20de9652d..bfb1f69fcff1 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -12,22 +12,15 @@
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/hwspinlock.h>
-#include <linux/io.h>
-#include <linux/init.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_address.h>
-#include <linux/of_platform.h>
-#include <linux/platform_data/syscon.h>
-#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/mfd/syscon.h>
#include <linux/slab.h>

-static struct platform_driver syscon_driver;
-
static DEFINE_MUTEX(syscon_list_lock);
static LIST_HEAD(syscon_list);

@@ -337,62 +330,3 @@ struct regmap *syscon_regmap_lookup_by_phandle_optional(struct device_node *np,
return regmap;
}
EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle_optional);
-
-static int syscon_probe(struct platform_device *pdev)
-{
- struct device *dev = &pdev->dev;
- struct syscon_platform_data *pdata = dev_get_platdata(dev);
- struct syscon *syscon;
- struct regmap_config syscon_config = syscon_regmap_config;
- struct resource *res;
- void __iomem *base;
-
- syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL);
- if (!syscon)
- return -ENOMEM;
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res)
- return -ENOENT;
-
- base = devm_ioremap(dev, res->start, resource_size(res));
- if (!base)
- return -ENOMEM;
-
- syscon_config.max_register = resource_size(res) - 4;
- if (!syscon_config.max_register)
- syscon_config.max_register_is_0 = true;
-
- if (pdata)
- syscon_config.name = pdata->label;
- syscon->regmap = devm_regmap_init_mmio(dev, base, &syscon_config);
- if (IS_ERR(syscon->regmap)) {
- dev_err(dev, "regmap init failed\n");
- return PTR_ERR(syscon->regmap);
- }
-
- platform_set_drvdata(pdev, syscon);
-
- dev_dbg(dev, "regmap %pR registered\n", res);
-
- return 0;
-}
-
-static const struct platform_device_id syscon_ids[] = {
- { "syscon", },
- { }
-};
-
-static struct platform_driver syscon_driver = {
- .driver = {
- .name = "syscon",
- },
- .probe = syscon_probe,
- .id_table = syscon_ids,
-};
-
-static int __init syscon_init(void)
-{
- return platform_driver_register(&syscon_driver);
-}
-postcore_initcall(syscon_init);
diff --git a/drivers/mfd/vexpress-sysreg.c b/drivers/mfd/vexpress-sysreg.c
index d34d58ce46db..ef03d6cec9ff 100644
--- a/drivers/mfd/vexpress-sysreg.c
+++ b/drivers/mfd/vexpress-sysreg.c
@@ -10,7 +10,6 @@
#include <linux/mfd/core.h>
#include <linux/module.h>
#include <linux/of_platform.h>
-#include <linux/platform_data/syscon.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/stat.h>
diff --git a/include/linux/platform_data/syscon.h b/include/linux/platform_data/syscon.h
deleted file mode 100644
index 2c089dd3e2bd..000000000000
--- a/include/linux/platform_data/syscon.h
+++ /dev/null
@@ -1,9 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef PLATFORM_DATA_SYSCON_H
-#define PLATFORM_DATA_SYSCON_H
-
-struct syscon_platform_data {
- const char *label;
-};
-
-#endif

--
2.45.2