Re: [PATCH v3 2/5] bcm2835-pm: Move bcm2835-watchdog's DT probe to an MFD.
From: Guenter Roeck
Date: Fri Nov 30 2018 - 17:10:50 EST
On Fri, Nov 30, 2018 at 12:27:40PM -0800, Eric Anholt wrote:
> The PM block that the wdt driver was binding to actually has multiple
> features we want to expose (power domains, reset, watchdog). Move the
> DT attachment to a MFD driver and make WDT probe against MFD.
>
> Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
For watchdog:
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> ---
>
> v3: don't reset bcm2835_power_off_wdt on remove, drop pm driver's
> empty remove, sort includes, add a "static".
>
> arch/arm/mach-bcm/Kconfig | 1 +
> drivers/mfd/Makefile | 1 +
> drivers/mfd/bcm2835-pm.c | 64 ++++++++++++++++++++++++++++++++++
> drivers/watchdog/bcm2835_wdt.c | 26 +++++---------
> include/linux/mfd/bcm2835-pm.h | 13 +++++++
> 5 files changed, 88 insertions(+), 17 deletions(-)
> create mode 100644 drivers/mfd/bcm2835-pm.c
> create mode 100644 include/linux/mfd/bcm2835-pm.h
>
> diff --git a/arch/arm/mach-bcm/Kconfig b/arch/arm/mach-bcm/Kconfig
> index 25aac6ee2ab1..95242c2162a2 100644
> --- a/arch/arm/mach-bcm/Kconfig
> +++ b/arch/arm/mach-bcm/Kconfig
> @@ -167,6 +167,7 @@ config ARCH_BCM2835
> select BCM2835_TIMER
> select PINCTRL
> select PINCTRL_BCM2835
> + select MFD_CORE
> help
> This enables support for the Broadcom BCM2835 and BCM2836 SoCs.
> This SoC is used in the Raspberry Pi and Roku 2 devices.
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 12980a4ad460..ee6fb6af655e 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -10,6 +10,7 @@ obj-$(CONFIG_MFD_88PM805) += 88pm805.o 88pm80x.o
> obj-$(CONFIG_MFD_ACT8945A) += act8945a.o
> obj-$(CONFIG_MFD_SM501) += sm501.o
> obj-$(CONFIG_MFD_ASIC3) += asic3.o tmio_core.o
> +obj-$(CONFIG_ARCH_BCM2835) += bcm2835-pm.o
> obj-$(CONFIG_MFD_BCM590XX) += bcm590xx.o
> obj-$(CONFIG_MFD_BD9571MWV) += bd9571mwv.o
> cros_ec_core-objs := cros_ec.o
> diff --git a/drivers/mfd/bcm2835-pm.c b/drivers/mfd/bcm2835-pm.c
> new file mode 100644
> index 000000000000..53839e6a81e7
> --- /dev/null
> +++ b/drivers/mfd/bcm2835-pm.c
> @@ -0,0 +1,64 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * PM MFD driver for Broadcom BCM2835
> + *
> + * This driver binds to the PM block and creates the MFD device for
> + * the WDT driver.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/mfd/bcm2835-pm.h>
> +#include <linux/mfd/core.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/types.h>
> +#include <linux/watchdog.h>
> +
> +static const struct mfd_cell bcm2835_pm_devs[] = {
> + { .name = "bcm2835-wdt" },
> +};
> +
> +static int bcm2835_pm_probe(struct platform_device *pdev)
> +{
> + struct resource *res;
> + struct device *dev = &pdev->dev;
> + struct bcm2835_pm *pm;
> +
> + pm = devm_kzalloc(dev, sizeof(*pm), GFP_KERNEL);
> + if (!pm)
> + return -ENOMEM;
> + platform_set_drvdata(pdev, pm);
> +
> + pm->dev = dev;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + pm->base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(pm->base))
> + return PTR_ERR(pm->base);
> +
> + return devm_mfd_add_devices(dev, -1,
> + bcm2835_pm_devs, ARRAY_SIZE(bcm2835_pm_devs),
> + NULL, 0, NULL);
> +}
> +
> +static const struct of_device_id bcm2835_pm_of_match[] = {
> + { .compatible = "brcm,bcm2835-pm-wdt", },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, bcm2835_pm_of_match);
> +
> +static struct platform_driver bcm2835_pm_driver = {
> + .probe = bcm2835_pm_probe,
> + .driver = {
> + .name = "bcm2835-pm",
> + .of_match_table = bcm2835_pm_of_match,
> + },
> +};
> +module_platform_driver(bcm2835_pm_driver);
> +
> +MODULE_AUTHOR("Eric Anholt <eric@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("Driver for Broadcom BCM2835 PM MFD");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/watchdog/bcm2835_wdt.c b/drivers/watchdog/bcm2835_wdt.c
> index ed05514cc2dc..1834524ae373 100644
> --- a/drivers/watchdog/bcm2835_wdt.c
> +++ b/drivers/watchdog/bcm2835_wdt.c
> @@ -12,6 +12,7 @@
>
> #include <linux/delay.h>
> #include <linux/types.h>
> +#include <linux/mfd/bcm2835-pm.h>
> #include <linux/module.h>
> #include <linux/io.h>
> #include <linux/watchdog.h>
> @@ -47,6 +48,8 @@ struct bcm2835_wdt {
> spinlock_t lock;
> };
>
> +static struct bcm2835_wdt *bcm2835_power_off_wdt;
> +
> static unsigned int heartbeat;
> static bool nowayout = WATCHDOG_NOWAYOUT;
>
> @@ -148,10 +151,7 @@ static struct watchdog_device bcm2835_wdt_wdd = {
> */
> static void bcm2835_power_off(void)
> {
> - struct device_node *np =
> - of_find_compatible_node(NULL, NULL, "brcm,bcm2835-pm-wdt");
> - struct platform_device *pdev = of_find_device_by_node(np);
> - struct bcm2835_wdt *wdt = platform_get_drvdata(pdev);
> + struct bcm2835_wdt *wdt = bcm2835_power_off_wdt;
> u32 val;
>
> /*
> @@ -169,7 +169,7 @@ static void bcm2835_power_off(void)
>
> static int bcm2835_wdt_probe(struct platform_device *pdev)
> {
> - struct resource *res;
> + struct bcm2835_pm *pm = dev_get_drvdata(pdev->dev.parent);
> struct device *dev = &pdev->dev;
> struct bcm2835_wdt *wdt;
> int err;
> @@ -181,10 +181,7 @@ static int bcm2835_wdt_probe(struct platform_device *pdev)
>
> spin_lock_init(&wdt->lock);
>
> - res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> - wdt->base = devm_ioremap_resource(dev, res);
> - if (IS_ERR(wdt->base))
> - return PTR_ERR(wdt->base);
> + wdt->base = pm->base;
>
> watchdog_set_drvdata(&bcm2835_wdt_wdd, wdt);
> watchdog_init_timeout(&bcm2835_wdt_wdd, heartbeat, dev);
> @@ -211,8 +208,10 @@ static int bcm2835_wdt_probe(struct platform_device *pdev)
> return err;
> }
>
> - if (pm_power_off == NULL)
> + if (pm_power_off == NULL) {
> pm_power_off = bcm2835_power_off;
> + bcm2835_power_off_wdt = wdt;
> + }
>
> dev_info(dev, "Broadcom BCM2835 watchdog timer");
> return 0;
> @@ -226,18 +225,11 @@ static int bcm2835_wdt_remove(struct platform_device *pdev)
> return 0;
> }
>
> -static const struct of_device_id bcm2835_wdt_of_match[] = {
> - { .compatible = "brcm,bcm2835-pm-wdt", },
> - {},
> -};
> -MODULE_DEVICE_TABLE(of, bcm2835_wdt_of_match);
> -
> static struct platform_driver bcm2835_wdt_driver = {
> .probe = bcm2835_wdt_probe,
> .remove = bcm2835_wdt_remove,
> .driver = {
> .name = "bcm2835-wdt",
> - .of_match_table = bcm2835_wdt_of_match,
> },
> };
> module_platform_driver(bcm2835_wdt_driver);
> diff --git a/include/linux/mfd/bcm2835-pm.h b/include/linux/mfd/bcm2835-pm.h
> new file mode 100644
> index 000000000000..b7d0ee1feffa
> --- /dev/null
> +++ b/include/linux/mfd/bcm2835-pm.h
> @@ -0,0 +1,13 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +
> +#ifndef BCM2835_MFD_PM_H
> +#define BCM2835_MFD_PM_H
> +
> +#include <linux/regmap.h>
> +
> +struct bcm2835_pm {
> + struct device *dev;
> + void __iomem *base;
> +};
> +
> +#endif /* BCM2835_MFD_PM_H */
> --
> 2.20.0.rc1
>