diff options
Diffstat (limited to 'kernel/drivers/power/reset/rmobile-reset.c')
-rw-r--r-- | kernel/drivers/power/reset/rmobile-reset.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/kernel/drivers/power/reset/rmobile-reset.c b/kernel/drivers/power/reset/rmobile-reset.c new file mode 100644 index 000000000..e6569df76 --- /dev/null +++ b/kernel/drivers/power/reset/rmobile-reset.c @@ -0,0 +1,91 @@ +/* + * Renesas R-Mobile Reset Driver + * + * Copyright (C) 2014 Glider bvba + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/io.h> +#include <linux/module.h> +#include <linux/notifier.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/printk.h> +#include <linux/reboot.h> + +/* SYSC Register Bank 2 */ +#define RESCNT2 0x20 /* Reset Control Register 2 */ + +/* Reset Control Register 2 */ +#define RESCNT2_PRES 0x80000000 /* Soft power-on reset */ + +static void __iomem *sysc_base2; + +static int rmobile_reset_handler(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + pr_debug("%s %lu\n", __func__, mode); + + /* Let's assume we have acquired the HPB semaphore */ + writel(RESCNT2_PRES, sysc_base2 + RESCNT2); + + return NOTIFY_DONE; +} + +static struct notifier_block rmobile_reset_nb = { + .notifier_call = rmobile_reset_handler, + .priority = 192, +}; + +static int rmobile_reset_probe(struct platform_device *pdev) +{ + int error; + + sysc_base2 = of_iomap(pdev->dev.of_node, 1); + if (!sysc_base2) + return -ENODEV; + + error = register_restart_handler(&rmobile_reset_nb); + if (error) { + dev_err(&pdev->dev, + "cannot register restart handler (err=%d)\n", error); + goto fail_unmap; + } + + return 0; + +fail_unmap: + iounmap(sysc_base2); + return error; +} + +static int rmobile_reset_remove(struct platform_device *pdev) +{ + unregister_restart_handler(&rmobile_reset_nb); + iounmap(sysc_base2); + return 0; +} + +static const struct of_device_id rmobile_reset_of_match[] = { + { .compatible = "renesas,sysc-rmobile", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rmobile_reset_of_match); + +static struct platform_driver rmobile_reset_driver = { + .probe = rmobile_reset_probe, + .remove = rmobile_reset_remove, + .driver = { + .name = "rmobile_reset", + .of_match_table = rmobile_reset_of_match, + }, +}; + +module_platform_driver(rmobile_reset_driver); + +MODULE_DESCRIPTION("Renesas R-Mobile Reset Driver"); +MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>"); +MODULE_LICENSE("GPL v2"); |