| Message ID | 20241217-syscon-fixes-v2-2-4f56d750541d@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mfd: syscon: Cleanup, fix race condition and remove platform driver | expand |
On 12/17/2024, Rob Herring (Arm) wrote: > 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. > > Tested-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> > Signed-off-by: Rob Herring (Arm) <robh@kernel.org> I verified this works on my Pixel 6. Thanks! Tested-by: Will McVicker <willmcvicker@google.com> Thanks, Will
On Tue, Dec 17, 2024 at 12:11:41PM -0600, Rob Herring (Arm) wrote: > 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. > > Tested-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> > Signed-off-by: Rob Herring (Arm) <robh@kernel.org> (Mostly for the vexpress-sysreg.c part, but hey, it's all code being removed): Acked-by: Liviu Dudau <liviu.dudau@arm.com> Best regards, Liviu > --- > 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 72f20de9652da2d7bad12e4bc2c43ac0c9a97f76..bfb1f69fcff1d3cd35cf04ccd4c449e7d0395c79 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 d34d58ce46db2ad0d53b3daeabc9d3763883b39a..ef03d6cec9ff6927668d051ca459eb1d8ff7269e 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 2c089dd3e2bda3baf5cef201ef43bca709e12c0b..0000000000000000000000000000000000000000 > --- 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 >
diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c index 72f20de9652da2d7bad12e4bc2c43ac0c9a97f76..bfb1f69fcff1d3cd35cf04ccd4c449e7d0395c79 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 d34d58ce46db2ad0d53b3daeabc9d3763883b39a..ef03d6cec9ff6927668d051ca459eb1d8ff7269e 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 2c089dd3e2bda3baf5cef201ef43bca709e12c0b..0000000000000000000000000000000000000000 --- 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
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. Tested-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> 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(-)