drivers/power/reset/imx-snvs-poweroff.c

   1 /* Power off driver for i.mx6
   2  * Copyright (c) 2014, FREESCALE CORPORATION.  All rights reserved.
   3  *
   4  * based on msm-poweroff.c
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 and
   8  * only version 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  */
  16
  17 #include <linux/err.h>
  18 #include <linux/init.h>
  19 #include <linux/io.h>
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/of.h>
  23 #include <linux/of_address.h>
  24 #include <linux/platform_device.h>
  25
  26 static void __iomem *snvs_base;
  27
  28 static void do_imx_poweroff(void)
  29 {
  30         u32 value = readl(snvs_base);
  31
  32         /* set TOP and DP_EN bit */
  33         writel(value | 0x60, snvs_base);
  34 }
  35
  36 static int imx_poweroff_probe(struct platform_device *pdev)
  37 {
  38         snvs_base = of_iomap(pdev->dev.of_node, 0);
  39         if (!snvs_base) {
  40                 dev_err(&pdev->dev, "failed to get memory\n");
  41                 return -ENODEV;
  42         }
  43
  44         pm_power_off = do_imx_poweroff;
  45         return 0;
  46 }
  47
  48 static const struct of_device_id of_imx_poweroff_match[] = {
  49         { .compatible = "fsl,sec-v4.0-poweroff", },
  50         {},
  51 };
  52 MODULE_DEVICE_TABLE(of, of_imx_poweroff_match);
  53
  54 static struct platform_driver imx_poweroff_driver = {
  55         .probe = imx_poweroff_probe,
  56         .driver = {
  57                 .name = "imx-snvs-poweroff",
  58                 .of_match_table = of_match_ptr(of_imx_poweroff_match),
  59         },
  60 };
  61
  62 static int __init imx_poweroff_init(void)
  63 {
  64         return platform_driver_register(&imx_poweroff_driver);
  65 }
  66 device_initcall(imx_poweroff_init);