target/linux/mediatek/patches-4.14/0136-mtd-mtk-nor-add-suspend-resume-support.patch

   1 From 8947f8cd407a55db816cd03fc03b59096210978e Mon Sep 17 00:00:00 2001
   2 From: Guochun Mao <guochun.mao@mediatek.com>
   3 Date: Thu, 21 Sep 2017 20:45:06 +0800
   4 Subject: [PATCH 136/224] mtd: mtk-nor: add suspend/resume support
   5
   6 Abstract functions of clock setting, to avoid duplicated code,
   7 these functions been used in new feature.
   8 Implement suspend/resume functions.
   9
  10 Signed-off-by: Guochun Mao <guochun.mao@mediatek.com>
  11 Signed-off-by: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
  12 ---
  13  drivers/mtd/spi-nor/mtk-quadspi.c | 70 ++++++++++++++++++++++++++++++++-------
  14  1 file changed, 58 insertions(+), 12 deletions(-)
  15
  16 --- a/drivers/mtd/spi-nor/mtk-quadspi.c
  17 +++ b/drivers/mtd/spi-nor/mtk-quadspi.c
  18 @@ -404,6 +404,29 @@ static int mt8173_nor_write_reg(struct s
  19         return ret;
  20  }
  21
  22 +static void mt8173_nor_disable_clk(struct mt8173_nor *mt8173_nor)
  23 +{
  24 +       clk_disable_unprepare(mt8173_nor->spi_clk);
  25 +       clk_disable_unprepare(mt8173_nor->nor_clk);
  26 +}
  27 +
  28 +static int mt8173_nor_enable_clk(struct mt8173_nor *mt8173_nor)
  29 +{
  30 +       int ret;
  31 +
  32 +       ret = clk_prepare_enable(mt8173_nor->spi_clk);
  33 +       if (ret)
  34 +               return ret;
  35 +
  36 +       ret = clk_prepare_enable(mt8173_nor->nor_clk);
  37 +       if (ret) {
  38 +               clk_disable_unprepare(mt8173_nor->spi_clk);
  39 +               return ret;
  40 +       }
  41 +
  42 +       return 0;
  43 +}
  44 +
  45  static int mtk_nor_init(struct mt8173_nor *mt8173_nor,
  46                         struct device_node *flash_node)
  47  {
  48 @@ -468,15 +491,11 @@ static int mtk_nor_drv_probe(struct plat
  49                 return PTR_ERR(mt8173_nor->nor_clk);
  50
  51         mt8173_nor->dev = &pdev->dev;
  52 -       ret = clk_prepare_enable(mt8173_nor->spi_clk);
  53 +
  54 +       ret = mt8173_nor_enable_clk(mt8173_nor);
  55         if (ret)
  56                 return ret;
  57
  58 -       ret = clk_prepare_enable(mt8173_nor->nor_clk);
  59 -       if (ret) {
  60 -               clk_disable_unprepare(mt8173_nor->spi_clk);
  61 -               return ret;
  62 -       }
  63         /* only support one attached flash */
  64         flash_np = of_get_next_available_child(pdev->dev.of_node, NULL);
  65         if (!flash_np) {
  66 @@ -487,10 +506,9 @@ static int mtk_nor_drv_probe(struct plat
  67         ret = mtk_nor_init(mt8173_nor, flash_np);
  68
  69  nor_free:
  70 -       if (ret) {
  71 -               clk_disable_unprepare(mt8173_nor->spi_clk);
  72 -               clk_disable_unprepare(mt8173_nor->nor_clk);
  73 -       }
  74 +       if (ret)
  75 +               mt8173_nor_disable_clk(mt8173_nor);
  76 +
  77         return ret;
  78  }
  79
  80 @@ -498,11 +516,38 @@ static int mtk_nor_drv_remove(struct pla
  81  {
  82         struct mt8173_nor *mt8173_nor = platform_get_drvdata(pdev);
  83
  84 -       clk_disable_unprepare(mt8173_nor->spi_clk);
  85 -       clk_disable_unprepare(mt8173_nor->nor_clk);
  86 +       mt8173_nor_disable_clk(mt8173_nor);
  87 +
  88 +       return 0;
  89 +}
  90 +
  91 +#ifdef CONFIG_PM_SLEEP
  92 +static int mtk_nor_suspend(struct device *dev)
  93 +{
  94 +       struct mt8173_nor *mt8173_nor = dev_get_drvdata(dev);
  95 +
  96 +       mt8173_nor_disable_clk(mt8173_nor);
  97 +
  98         return 0;
  99  }
 100
 101 +static int mtk_nor_resume(struct device *dev)
 102 +{
 103 +       struct mt8173_nor *mt8173_nor = dev_get_drvdata(dev);
 104 +
 105 +       return mt8173_nor_enable_clk(mt8173_nor);
 106 +}
 107 +
 108 +static const struct dev_pm_ops mtk_nor_dev_pm_ops = {
 109 +       .suspend = mtk_nor_suspend,
 110 +       .resume = mtk_nor_resume,
 111 +};
 112 +
 113 +#define MTK_NOR_DEV_PM_OPS     (&mtk_nor_dev_pm_ops)
 114 +#else
 115 +#define MTK_NOR_DEV_PM_OPS     NULL
 116 +#endif
 117 +
 118  static const struct of_device_id mtk_nor_of_ids[] = {
 119         { .compatible = "mediatek,mt8173-nor"},
 120         { /* sentinel */ }
 121 @@ -514,6 +559,7 @@ static struct platform_driver mtk_nor_dr
 122         .remove = mtk_nor_drv_remove,
 123         .driver = {
 124                 .name = "mtk-nor",
 125 +               .pm = MTK_NOR_DEV_PM_OPS,
 126                 .of_match_table = mtk_nor_of_ids,
 127         },
 128  };