Re: [PATCH v9 2/4] power: reset: add reboot mode driver
From: Krzysztof Kozlowski <hidden>
Date: 2016-07-06 13:39:51
Also in:
linux-devicetree, lkml
On 06/20/2016 08:38 AM, Andy Yan wrote:
This driver parses the reboot commands like "reboot bootloader" and "reboot recovery" to get a boot mode described in the device tree , then call the write interfae to store the boot mode in some place like special register or sram, which can be read by the bootloader after system reboot, then the bootloader can take different action according to the mode stored. This is commonly used on Android based devices, in order to reboot the device into fastboot or recovery mode. Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com> Reviewed-by: Moritz Fischer <moritz.fischer@ettus.com> Tested-by: John Stultz <redacted> Acked-by: John Stultz <redacted> Signed-off-by: Andy Yan <andy.yan@rock-chips.com> --- Changes in v9: - select MFD_SYSCON when syscon-reboot-mode driver enabled - refactoring error handling in reboot_mode_register Changes in v8: - do some cleanup when driver ubind Changes in v7: - address some suggestions from Krzysztof, make syscon-reboot-mode driver data self-contained. Changes in v6: None Changes in v5: - use two blank space under help in Kconfig - use unsigned int instead of int for member magic in struct mode_info Changes in v4: - make this driver depends on OF to avoid kbuild test error Changes in v3: - scan multi properities - add mask value for some platform which only use some bits of the register to store boot mode magic value Changes in v2: - move to dir drivers/power/reset/ - make syscon-reboot-mode a generic driver Changes in v1: - fix the embarrassed compile warning - correct the maskrom magic number - check for the normal reboot drivers/power/reset/Kconfig | 14 ++++ drivers/power/reset/Makefile | 2 + drivers/power/reset/reboot-mode.c | 128 +++++++++++++++++++++++++++++++ drivers/power/reset/reboot-mode.h | 14 ++++ drivers/power/reset/syscon-reboot-mode.c | 100 ++++++++++++++++++++++++ 5 files changed, 258 insertions(+) create mode 100644 drivers/power/reset/reboot-mode.c create mode 100644 drivers/power/reset/reboot-mode.h create mode 100644 drivers/power/reset/syscon-reboot-mode.c
One minor whitespace issue at the end but beside that: Reviewed-by: Krzysztof Kozlowski <redacted> (...)
quoted hunk ↗ jump to hunk
diff --git a/drivers/power/reset/syscon-reboot-mode.c b/drivers/power/reset/syscon-reboot-mode.c new file mode 100644 index 0000000..22e0685 --- /dev/null +++ b/drivers/power/reset/syscon-reboot-mode.c@@ -0,0 +1,100 @@ +/* + * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reboot.h> +#include <linux/regmap.h> +#include <linux/mfd/syscon.h> +#include "reboot-mode.h" + +struct syscon_reboot_mode { + struct regmap *map; + struct reboot_mode_driver reboot; + u32 offset; + u32 mask; +}; + +static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot, + unsigned int magic) +{ + struct syscon_reboot_mode *syscon_rbm; + int ret; + + syscon_rbm = container_of(reboot, struct syscon_reboot_mode, reboot); + + ret = regmap_update_bits(syscon_rbm->map, syscon_rbm->offset, + syscon_rbm->mask, magic); + if (ret < 0) + dev_err(reboot->dev, "update reboot mode bits failed\n"); + + return ret; +} + +static int syscon_reboot_mode_probe(struct platform_device *pdev) +{ + int ret; + struct syscon_reboot_mode *syscon_rbm; + + syscon_rbm = devm_kzalloc(&pdev->dev, sizeof(*syscon_rbm), GFP_KERNEL); + if (!syscon_rbm) + return -ENOMEM; + + syscon_rbm->reboot.dev = &pdev->dev; + syscon_rbm->reboot.write = syscon_reboot_mode_write; + syscon_rbm->mask = 0xffffffff; + + dev_set_drvdata(&pdev->dev, syscon_rbm); + + syscon_rbm->map = syscon_node_to_regmap(pdev->dev.parent->of_node); + if (IS_ERR(syscon_rbm->map)) + return PTR_ERR(syscon_rbm->map); + + if (of_property_read_u32(pdev->dev.of_node, "offset", + &syscon_rbm->offset)) + return -EINVAL; + + of_property_read_u32(pdev->dev.of_node, "mask", &syscon_rbm->mask); + +
Just one new line. Best regards, Krzysztof
+ ret = reboot_mode_register(&syscon_rbm->reboot);
+ if (ret)
+ dev_err(&pdev->dev, "can't register reboot mode\n");
+
+ return ret;
+}
+
+static int syscon_reboot_mode_remove(struct platform_device *pdev)
+{
+ struct syscon_reboot_mode *syscon_rbm = dev_get_drvdata(&pdev->dev);
+
+ return reboot_mode_unregister(&syscon_rbm->reboot);
+}
+
+static const struct of_device_id syscon_reboot_mode_of_match[] = {
+ { .compatible = "syscon-reboot-mode" },
+ {}
+};
+
+static struct platform_driver syscon_reboot_mode_driver = {
+ .probe = syscon_reboot_mode_probe,
+ .remove = syscon_reboot_mode_remove,
+ .driver = {
+ .name = "syscon-reboot-mode",
+ .of_match_table = syscon_reboot_mode_of_match,
+ },
+};
+module_platform_driver(syscon_reboot_mode_driver);
+
+MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com");
+MODULE_DESCRIPTION("SYSCON reboot mode driver");
+MODULE_LICENSE("GPL v2");