target/linux/generic/backport-5.15/813-v6.5-0011-nvmem-core-add-support-for-fixed-cells-layout.patch

   1 From 27f699e578b1a72df89dfa3bc42e093a01dc8d10 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
   3 Date: Sun, 11 Jun 2023 15:03:29 +0100
   4 Subject: [PATCH] nvmem: core: add support for fixed cells *layout*
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 This adds support for the "fixed-layout" NVMEM layout binding. It allows
  10 defining NVMEM cells in a layout DT node named "nvmem-layout".
  11
  12 While NVMEM subsystem supports layout drivers it has been discussed that
  13 "fixed-layout" may actually be supperted internally. It's because:
  14 1. It's a very basic layout
  15 2. It allows sharing code with legacy syntax parsing
  16 3. It's safer for soc_device_match() due to -EPROBE_DEFER
  17 4. This will make the syntax transition easier
  18
  19 Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
  20 Reviewed-by: Michael Walle <michael@walle.cc>
  21 Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
  22 Message-ID: <20230611140330.154222-26-srinivas.kandagatla@linaro.org>
  23 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  24 ---
  25  drivers/nvmem/core.c | 32 +++++++++++++++++++++++++++++---
  26  1 file changed, 29 insertions(+), 3 deletions(-)
  27
  28 --- a/drivers/nvmem/core.c
  29 +++ b/drivers/nvmem/core.c
  30 @@ -696,7 +696,7 @@ static int nvmem_validate_keepouts(struc
  31         return 0;
  32  }
  33
  34 -static int nvmem_add_cells_from_of(struct nvmem_device *nvmem)
  35 +static int nvmem_add_cells_from_dt(struct nvmem_device *nvmem, struct device_node *np)
  36  {
  37         struct nvmem_layout *layout = nvmem->layout;
  38         struct device *dev = &nvmem->dev;
  39 @@ -704,7 +704,7 @@ static int nvmem_add_cells_from_of(struc
  40         const __be32 *addr;
  41         int len, ret;
  42
  43 -       for_each_child_of_node(dev->of_node, child) {
  44 +       for_each_child_of_node(np, child) {
  45                 struct nvmem_cell_info info = {0};
  46
  47                 addr = of_get_property(child, "reg", &len);
  48 @@ -742,6 +742,28 @@ static int nvmem_add_cells_from_of(struc
  49         return 0;
  50  }
  51
  52 +static int nvmem_add_cells_from_legacy_of(struct nvmem_device *nvmem)
  53 +{
  54 +       return nvmem_add_cells_from_dt(nvmem, nvmem->dev.of_node);
  55 +}
  56 +
  57 +static int nvmem_add_cells_from_fixed_layout(struct nvmem_device *nvmem)
  58 +{
  59 +       struct device_node *layout_np;
  60 +       int err = 0;
  61 +
  62 +       layout_np = of_nvmem_layout_get_container(nvmem);
  63 +       if (!layout_np)
  64 +               return 0;
  65 +
  66 +       if (of_device_is_compatible(layout_np, "fixed-layout"))
  67 +               err = nvmem_add_cells_from_dt(nvmem, layout_np);
  68 +
  69 +       of_node_put(layout_np);
  70 +
  71 +       return err;
  72 +}
  73 +
  74  int __nvmem_layout_register(struct nvmem_layout *layout, struct module *owner)
  75  {
  76         layout->owner = owner;
  77 @@ -972,7 +994,7 @@ struct nvmem_device *nvmem_register(cons
  78         if (rval)
  79                 goto err_remove_cells;
  80
  81 -       rval = nvmem_add_cells_from_of(nvmem);
  82 +       rval = nvmem_add_cells_from_legacy_of(nvmem);
  83         if (rval)
  84                 goto err_remove_cells;
  85
  86 @@ -982,6 +1004,10 @@ struct nvmem_device *nvmem_register(cons
  87         if (rval)
  88                 goto err_remove_cells;
  89
  90 +       rval = nvmem_add_cells_from_fixed_layout(nvmem);
  91 +       if (rval)
  92 +               goto err_remove_cells;
  93 +
  94         rval = nvmem_add_cells_from_layout(nvmem);
  95         if (rval)
  96                 goto err_remove_cells;