kernel: backport patches simplifying mtd_device_parse_register code
authorRafał Miłecki <rafal@milecki.pl>
Mon, 19 Feb 2018 14:40:42 +0000 (15:40 +0100)
committerRafał Miłecki <rafal@milecki.pl>
Mon, 19 Feb 2018 15:01:44 +0000 (16:01 +0100)
These 2 patches were recently queued for 4.17.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
target/linux/generic/backport-4.14/040-v4.17-0001-mtd-move-code-adding-master-MTD-out-of-mtd_add_devic.patch [new file with mode: 0644]
target/linux/generic/backport-4.14/040-v4.17-0002-mtd-get-rid-of-the-mtd_add_device_partitions.patch [new file with mode: 0644]
target/linux/generic/backport-4.9/066-v4.16-0001-mtd-partitions-add-of_match_table-parser-matching.patch [deleted file]
target/linux/generic/backport-4.9/066-v4.16-0002-mtd-ofpart-add-of_match_table-with-fixed-partitions.patch [deleted file]
target/linux/generic/backport-4.9/066-v4.17-0001-mtd-move-code-adding-master-MTD-out-of-mtd_add_devic.patch [new file with mode: 0644]
target/linux/generic/backport-4.9/066-v4.17-0002-mtd-get-rid-of-the-mtd_add_device_partitions.patch [new file with mode: 0644]
target/linux/generic/backport-4.9/067-v4.17-0001-mtd-partitions-add-of_match_table-parser-matching.patch [new file with mode: 0644]
target/linux/generic/backport-4.9/067-v4.17-0002-mtd-ofpart-add-of_match_table-with-fixed-partitions.patch [new file with mode: 0644]
target/linux/generic/pending-4.14/812-pci-dwc-fix-enumeration.patch

diff --git a/target/linux/generic/backport-4.14/040-v4.17-0001-mtd-move-code-adding-master-MTD-out-of-mtd_add_devic.patch b/target/linux/generic/backport-4.14/040-v4.17-0001-mtd-move-code-adding-master-MTD-out-of-mtd_add_devic.patch
new file mode 100644 (file)
index 0000000..df64297
--- /dev/null
@@ -0,0 +1,74 @@
+From 2c77c57d22adb05b21cdb333a0c42bdfa0e19835 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Tue, 16 Jan 2018 16:45:41 +0100
+Subject: [PATCH] mtd: move code adding master MTD out of
+ mtd_add_device_partitions()
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This change is a small cleanup of mtd_device_parse_register(). When
+using MTD_PARTITIONED_MASTER it makes sure a master MTD is registered
+before dealing with partitions. The advantage of this is not mixing
+code handling master MTD with code handling partitions.
+
+This commit doesn't change any behavior except from a slightly different
+failure code path. The new code may need to call del_mtd_device when
+something goes wrong.
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
+---
+ drivers/mtd/mtdcore.c | 25 +++++++++++++------------
+ 1 file changed, 13 insertions(+), 12 deletions(-)
+
+--- a/drivers/mtd/mtdcore.c
++++ b/drivers/mtd/mtdcore.c
+@@ -641,20 +641,12 @@ static int mtd_add_device_partitions(str
+ {
+       const struct mtd_partition *real_parts = parts->parts;
+       int nbparts = parts->nr_parts;
+-      int ret;
+-      if (nbparts == 0 || IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) {
+-              ret = add_mtd_device(mtd);
+-              if (ret)
+-                      return ret;
+-      }
++      if (!nbparts && !device_is_registered(&mtd->dev))
++              return add_mtd_device(mtd);
+-      if (nbparts > 0) {
+-              ret = add_mtd_partitions(mtd, real_parts, nbparts);
+-              if (ret && IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))
+-                      del_mtd_device(mtd);
+-              return ret;
+-      }
++      if (nbparts > 0)
++              return add_mtd_partitions(mtd, real_parts, nbparts);
+       return 0;
+ }
+@@ -714,6 +706,12 @@ int mtd_device_parse_register(struct mtd
+       mtd_set_dev_defaults(mtd);
++      if (IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) {
++              ret = add_mtd_device(mtd);
++              if (ret)
++                      return ret;
++      }
++
+       memset(&parsed, 0, sizeof(parsed));
+       ret = parse_mtd_partitions(mtd, types, &parsed, parser_data);
+@@ -753,6 +751,9 @@ int mtd_device_parse_register(struct mtd
+ out:
+       /* Cleanup any parsed partitions */
+       mtd_part_parser_cleanup(&parsed);
++      if (ret && device_is_registered(&mtd->dev))
++              del_mtd_device(mtd);
++
+       return ret;
+ }
+ EXPORT_SYMBOL_GPL(mtd_device_parse_register);
diff --git a/target/linux/generic/backport-4.14/040-v4.17-0002-mtd-get-rid-of-the-mtd_add_device_partitions.patch b/target/linux/generic/backport-4.14/040-v4.17-0002-mtd-get-rid-of-the-mtd_add_device_partitions.patch
new file mode 100644 (file)
index 0000000..1042e67
--- /dev/null
@@ -0,0 +1,93 @@
+From 0dbe4ea78d69756efeb0bba0764f6bd4a9ee9567 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Tue, 16 Jan 2018 16:45:42 +0100
+Subject: [PATCH] mtd: get rid of the mtd_add_device_partitions()
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This simplifies code a bit by:
+1) Avoiding an extra (tiny) function
+2) Checking for amount of parsed (found) partitions just once
+3) Avoiding clearing/filling struct mtd_partitions manually
+
+With this commit proper functions are called directly from the
+mtd_device_parse_register(). It doesn't need to use minor tricks like
+memsetting struct to 0 to trigger an expected
+mtd_add_device_partitions() behavior.
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
+---
+ drivers/mtd/mtdcore.c | 43 ++++++++++++-------------------------------
+ 1 file changed, 12 insertions(+), 31 deletions(-)
+
+--- a/drivers/mtd/mtdcore.c
++++ b/drivers/mtd/mtdcore.c
+@@ -636,21 +636,6 @@ out_error:
+       return ret;
+ }
+-static int mtd_add_device_partitions(struct mtd_info *mtd,
+-                                   struct mtd_partitions *parts)
+-{
+-      const struct mtd_partition *real_parts = parts->parts;
+-      int nbparts = parts->nr_parts;
+-
+-      if (!nbparts && !device_is_registered(&mtd->dev))
+-              return add_mtd_device(mtd);
+-
+-      if (nbparts > 0)
+-              return add_mtd_partitions(mtd, real_parts, nbparts);
+-
+-      return 0;
+-}
+-
+ /*
+  * Set a few defaults based on the parent devices, if not provided by the
+  * driver
+@@ -701,7 +686,7 @@ int mtd_device_parse_register(struct mtd
+                             const struct mtd_partition *parts,
+                             int nr_parts)
+ {
+-      struct mtd_partitions parsed;
++      struct mtd_partitions parsed = { };
+       int ret;
+       mtd_set_dev_defaults(mtd);
+@@ -712,24 +697,20 @@ int mtd_device_parse_register(struct mtd
+                       return ret;
+       }
+-      memset(&parsed, 0, sizeof(parsed));
+-
++      /* Prefer parsed partitions over driver-provided fallback */
+       ret = parse_mtd_partitions(mtd, types, &parsed, parser_data);
+-      if ((ret < 0 || parsed.nr_parts == 0) && parts && nr_parts) {
+-              /* Fall back to driver-provided partitions */
+-              parsed = (struct mtd_partitions){
+-                      .parts          = parts,
+-                      .nr_parts       = nr_parts,
+-              };
+-      } else if (ret < 0) {
+-              /* Didn't come up with parsed OR fallback partitions */
+-              pr_info("mtd: failed to find partitions; one or more parsers reports errors (%d)\n",
+-                      ret);
+-              /* Don't abort on errors; we can still use unpartitioned MTD */
+-              memset(&parsed, 0, sizeof(parsed));
++      if (!ret && parsed.nr_parts) {
++              parts = parsed.parts;
++              nr_parts = parsed.nr_parts;
+       }
+-      ret = mtd_add_device_partitions(mtd, &parsed);
++      if (nr_parts)
++              ret = add_mtd_partitions(mtd, parts, nr_parts);
++      else if (!device_is_registered(&mtd->dev))
++              ret = add_mtd_device(mtd);
++      else
++              ret = 0;
++
+       if (ret)
+               goto out;
diff --git a/target/linux/generic/backport-4.9/066-v4.16-0001-mtd-partitions-add-of_match_table-parser-matching.patch b/target/linux/generic/backport-4.9/066-v4.16-0001-mtd-partitions-add-of_match_table-parser-matching.patch
deleted file mode 100644 (file)
index 06931ce..0000000
+++ /dev/null
@@ -1,121 +0,0 @@
-From bb2192123ec70470d6ea33f138846b175403a968 Mon Sep 17 00:00:00 2001
-From: Brian Norris <computersforpeace@gmail.com>
-Date: Thu, 4 Jan 2018 08:05:33 +0100
-Subject: [PATCH] mtd: partitions: add of_match_table parser matching
-MIME-Version: 1.0
-Content-Type: text/plain; charset=UTF-8
-Content-Transfer-Encoding: 8bit
-
-Partition parsers can now provide an of_match_table to enable
-flash<-->parser matching via device tree as documented in the
-mtd/partition.txt.
-
-It works by looking for a matching parser for every string in the
-"compatibility" property (starting with the most specific one).
-
-This support is currently limited to built-in parsers as it uses
-request_module() and friends. This should be sufficient for most cases
-though as compiling parsers as modules isn't a common choice.
-
-Signed-off-by: Brian Norris <computersforpeace@gmail.com>
-Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
-Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
----
- drivers/mtd/mtdpart.c          | 59 ++++++++++++++++++++++++++++++++++++++++++
- include/linux/mtd/partitions.h |  1 +
- 2 files changed, 60 insertions(+)
-
---- a/drivers/mtd/mtdpart.c
-+++ b/drivers/mtd/mtdpart.c
-@@ -30,6 +30,7 @@
- #include <linux/mtd/mtd.h>
- #include <linux/mtd/partitions.h>
- #include <linux/err.h>
-+#include <linux/of.h>
- #include "mtdcore.h"
-@@ -886,6 +887,45 @@ static int mtd_part_do_parse(struct mtd_
- }
- /**
-+ * mtd_part_get_compatible_parser - find MTD parser by a compatible string
-+ *
-+ * @compat: compatible string describing partitions in a device tree
-+ *
-+ * MTD parsers can specify supported partitions by providing a table of
-+ * compatibility strings. This function finds a parser that advertises support
-+ * for a passed value of "compatible".
-+ */
-+static struct mtd_part_parser *mtd_part_get_compatible_parser(const char *compat)
-+{
-+      struct mtd_part_parser *p, *ret = NULL;
-+
-+      spin_lock(&part_parser_lock);
-+
-+      list_for_each_entry(p, &part_parsers, list) {
-+              const struct of_device_id *matches;
-+
-+              matches = p->of_match_table;
-+              if (!matches)
-+                      continue;
-+
-+              for (; matches->compatible[0]; matches++) {
-+                      if (!strcmp(matches->compatible, compat) &&
-+                          try_module_get(p->owner)) {
-+                              ret = p;
-+                              break;
-+                      }
-+              }
-+
-+              if (ret)
-+                      break;
-+      }
-+
-+      spin_unlock(&part_parser_lock);
-+
-+      return ret;
-+}
-+
-+/**
-  * parse_mtd_partitions - parse MTD partitions
-  * @master: the master partition (describes whole MTD device)
-  * @types: names of partition parsers to try or %NULL
-@@ -911,8 +951,27 @@ int parse_mtd_partitions(struct mtd_info
-                        struct mtd_part_parser_data *data)
- {
-       struct mtd_part_parser *parser;
-+      struct device_node *np;
-+      struct property *prop;
-+      const char *compat;
-       int ret, err = 0;
-+      np = of_get_child_by_name(mtd_get_of_node(master), "partitions");
-+      of_property_for_each_string(np, "compatible", prop, compat) {
-+              parser = mtd_part_get_compatible_parser(compat);
-+              if (!parser)
-+                      continue;
-+              ret = mtd_part_do_parse(parser, master, pparts, data);
-+              if (ret > 0) {
-+                      of_node_put(np);
-+                      return 0;
-+              }
-+              mtd_part_parser_put(parser);
-+              if (ret < 0 && !err)
-+                      err = ret;
-+      }
-+      of_node_put(np);
-+
-       if (!types)
-               types = default_mtd_part_types;
---- a/include/linux/mtd/partitions.h
-+++ b/include/linux/mtd/partitions.h
-@@ -77,6 +77,7 @@ struct mtd_part_parser {
-       struct list_head list;
-       struct module *owner;
-       const char *name;
-+      const struct of_device_id *of_match_table;
-       int (*parse_fn)(struct mtd_info *, const struct mtd_partition **,
-                       struct mtd_part_parser_data *);
-       void (*cleanup)(const struct mtd_partition *pparts, int nr_parts);
diff --git a/target/linux/generic/backport-4.9/066-v4.16-0002-mtd-ofpart-add-of_match_table-with-fixed-partitions.patch b/target/linux/generic/backport-4.9/066-v4.16-0002-mtd-ofpart-add-of_match_table-with-fixed-partitions.patch
deleted file mode 100644 (file)
index 2092cc2..0000000
+++ /dev/null
@@ -1,43 +0,0 @@
-From 4ac9222778478a00c7fc9d347b7ed1e0e595120d Mon Sep 17 00:00:00 2001
-From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
-Date: Thu, 4 Jan 2018 08:05:34 +0100
-Subject: [PATCH] mtd: ofpart: add of_match_table with "fixed-partitions"
-MIME-Version: 1.0
-Content-Type: text/plain; charset=UTF-8
-Content-Transfer-Encoding: 8bit
-
-This allows using this parser with any flash driver that takes care of
-setting of_node (using mtd_set_of_node helper) correctly. Up to now
-support for "fixed-partitions" DT compatibility string was working only
-with flash drivers that were specifying "ofpart" (manually or by letting
-mtd use the default set of parsers).
-
-This matches existing bindings documentation.
-
-Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
-Reviewed-by: Brian Norris <computersforpeace@gmail.com>
-Tested-by: Brian Norris <computersforpeace@gmail.com>
-Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
----
- drivers/mtd/ofpart.c | 7 +++++++
- 1 file changed, 7 insertions(+)
-
---- a/drivers/mtd/ofpart.c
-+++ b/drivers/mtd/ofpart.c
-@@ -140,9 +140,16 @@ ofpart_none:
-       return ret;
- }
-+static const struct of_device_id parse_ofpart_match_table[] = {
-+      { .compatible = "fixed-partitions" },
-+      {},
-+};
-+MODULE_DEVICE_TABLE(of, parse_ofpart_match_table);
-+
- static struct mtd_part_parser ofpart_parser = {
-       .parse_fn = parse_ofpart_partitions,
-       .name = "ofpart",
-+      .of_match_table = parse_ofpart_match_table,
- };
- static int parse_ofoldpart_partitions(struct mtd_info *master,
diff --git a/target/linux/generic/backport-4.9/066-v4.17-0001-mtd-move-code-adding-master-MTD-out-of-mtd_add_devic.patch b/target/linux/generic/backport-4.9/066-v4.17-0001-mtd-move-code-adding-master-MTD-out-of-mtd_add_devic.patch
new file mode 100644 (file)
index 0000000..07a456d
--- /dev/null
@@ -0,0 +1,74 @@
+From 2c77c57d22adb05b21cdb333a0c42bdfa0e19835 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Tue, 16 Jan 2018 16:45:41 +0100
+Subject: [PATCH] mtd: move code adding master MTD out of
+ mtd_add_device_partitions()
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This change is a small cleanup of mtd_device_parse_register(). When
+using MTD_PARTITIONED_MASTER it makes sure a master MTD is registered
+before dealing with partitions. The advantage of this is not mixing
+code handling master MTD with code handling partitions.
+
+This commit doesn't change any behavior except from a slightly different
+failure code path. The new code may need to call del_mtd_device when
+something goes wrong.
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
+---
+ drivers/mtd/mtdcore.c | 25 +++++++++++++------------
+ 1 file changed, 13 insertions(+), 12 deletions(-)
+
+--- a/drivers/mtd/mtdcore.c
++++ b/drivers/mtd/mtdcore.c
+@@ -631,20 +631,12 @@ static int mtd_add_device_partitions(str
+ {
+       const struct mtd_partition *real_parts = parts->parts;
+       int nbparts = parts->nr_parts;
+-      int ret;
+-      if (nbparts == 0 || IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) {
+-              ret = add_mtd_device(mtd);
+-              if (ret)
+-                      return ret;
+-      }
++      if (!nbparts && !device_is_registered(&mtd->dev))
++              return add_mtd_device(mtd);
+-      if (nbparts > 0) {
+-              ret = add_mtd_partitions(mtd, real_parts, nbparts);
+-              if (ret && IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))
+-                      del_mtd_device(mtd);
+-              return ret;
+-      }
++      if (nbparts > 0)
++              return add_mtd_partitions(mtd, real_parts, nbparts);
+       return 0;
+ }
+@@ -704,6 +696,12 @@ int mtd_device_parse_register(struct mtd
+       mtd_set_dev_defaults(mtd);
++      if (IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) {
++              ret = add_mtd_device(mtd);
++              if (ret)
++                      return ret;
++      }
++
+       memset(&parsed, 0, sizeof(parsed));
+       ret = parse_mtd_partitions(mtd, types, &parsed, parser_data);
+@@ -743,6 +741,9 @@ int mtd_device_parse_register(struct mtd
+ out:
+       /* Cleanup any parsed partitions */
+       mtd_part_parser_cleanup(&parsed);
++      if (ret && device_is_registered(&mtd->dev))
++              del_mtd_device(mtd);
++
+       return ret;
+ }
+ EXPORT_SYMBOL_GPL(mtd_device_parse_register);
diff --git a/target/linux/generic/backport-4.9/066-v4.17-0002-mtd-get-rid-of-the-mtd_add_device_partitions.patch b/target/linux/generic/backport-4.9/066-v4.17-0002-mtd-get-rid-of-the-mtd_add_device_partitions.patch
new file mode 100644 (file)
index 0000000..b629d43
--- /dev/null
@@ -0,0 +1,93 @@
+From 0dbe4ea78d69756efeb0bba0764f6bd4a9ee9567 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Tue, 16 Jan 2018 16:45:42 +0100
+Subject: [PATCH] mtd: get rid of the mtd_add_device_partitions()
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This simplifies code a bit by:
+1) Avoiding an extra (tiny) function
+2) Checking for amount of parsed (found) partitions just once
+3) Avoiding clearing/filling struct mtd_partitions manually
+
+With this commit proper functions are called directly from the
+mtd_device_parse_register(). It doesn't need to use minor tricks like
+memsetting struct to 0 to trigger an expected
+mtd_add_device_partitions() behavior.
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
+---
+ drivers/mtd/mtdcore.c | 43 ++++++++++++-------------------------------
+ 1 file changed, 12 insertions(+), 31 deletions(-)
+
+--- a/drivers/mtd/mtdcore.c
++++ b/drivers/mtd/mtdcore.c
+@@ -626,21 +626,6 @@ out_error:
+       return ret;
+ }
+-static int mtd_add_device_partitions(struct mtd_info *mtd,
+-                                   struct mtd_partitions *parts)
+-{
+-      const struct mtd_partition *real_parts = parts->parts;
+-      int nbparts = parts->nr_parts;
+-
+-      if (!nbparts && !device_is_registered(&mtd->dev))
+-              return add_mtd_device(mtd);
+-
+-      if (nbparts > 0)
+-              return add_mtd_partitions(mtd, real_parts, nbparts);
+-
+-      return 0;
+-}
+-
+ /*
+  * Set a few defaults based on the parent devices, if not provided by the
+  * driver
+@@ -691,7 +676,7 @@ int mtd_device_parse_register(struct mtd
+                             const struct mtd_partition *parts,
+                             int nr_parts)
+ {
+-      struct mtd_partitions parsed;
++      struct mtd_partitions parsed = { };
+       int ret;
+       mtd_set_dev_defaults(mtd);
+@@ -702,24 +687,20 @@ int mtd_device_parse_register(struct mtd
+                       return ret;
+       }
+-      memset(&parsed, 0, sizeof(parsed));
+-
++      /* Prefer parsed partitions over driver-provided fallback */
+       ret = parse_mtd_partitions(mtd, types, &parsed, parser_data);
+-      if ((ret < 0 || parsed.nr_parts == 0) && parts && nr_parts) {
+-              /* Fall back to driver-provided partitions */
+-              parsed = (struct mtd_partitions){
+-                      .parts          = parts,
+-                      .nr_parts       = nr_parts,
+-              };
+-      } else if (ret < 0) {
+-              /* Didn't come up with parsed OR fallback partitions */
+-              pr_info("mtd: failed to find partitions; one or more parsers reports errors (%d)\n",
+-                      ret);
+-              /* Don't abort on errors; we can still use unpartitioned MTD */
+-              memset(&parsed, 0, sizeof(parsed));
++      if (!ret && parsed.nr_parts) {
++              parts = parsed.parts;
++              nr_parts = parsed.nr_parts;
+       }
+-      ret = mtd_add_device_partitions(mtd, &parsed);
++      if (nr_parts)
++              ret = add_mtd_partitions(mtd, parts, nr_parts);
++      else if (!device_is_registered(&mtd->dev))
++              ret = add_mtd_device(mtd);
++      else
++              ret = 0;
++
+       if (ret)
+               goto out;
diff --git a/target/linux/generic/backport-4.9/067-v4.17-0001-mtd-partitions-add-of_match_table-parser-matching.patch b/target/linux/generic/backport-4.9/067-v4.17-0001-mtd-partitions-add-of_match_table-parser-matching.patch
new file mode 100644 (file)
index 0000000..06931ce
--- /dev/null
@@ -0,0 +1,121 @@
+From bb2192123ec70470d6ea33f138846b175403a968 Mon Sep 17 00:00:00 2001
+From: Brian Norris <computersforpeace@gmail.com>
+Date: Thu, 4 Jan 2018 08:05:33 +0100
+Subject: [PATCH] mtd: partitions: add of_match_table parser matching
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Partition parsers can now provide an of_match_table to enable
+flash<-->parser matching via device tree as documented in the
+mtd/partition.txt.
+
+It works by looking for a matching parser for every string in the
+"compatibility" property (starting with the most specific one).
+
+This support is currently limited to built-in parsers as it uses
+request_module() and friends. This should be sufficient for most cases
+though as compiling parsers as modules isn't a common choice.
+
+Signed-off-by: Brian Norris <computersforpeace@gmail.com>
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
+---
+ drivers/mtd/mtdpart.c          | 59 ++++++++++++++++++++++++++++++++++++++++++
+ include/linux/mtd/partitions.h |  1 +
+ 2 files changed, 60 insertions(+)
+
+--- a/drivers/mtd/mtdpart.c
++++ b/drivers/mtd/mtdpart.c
+@@ -30,6 +30,7 @@
+ #include <linux/mtd/mtd.h>
+ #include <linux/mtd/partitions.h>
+ #include <linux/err.h>
++#include <linux/of.h>
+ #include "mtdcore.h"
+@@ -886,6 +887,45 @@ static int mtd_part_do_parse(struct mtd_
+ }
+ /**
++ * mtd_part_get_compatible_parser - find MTD parser by a compatible string
++ *
++ * @compat: compatible string describing partitions in a device tree
++ *
++ * MTD parsers can specify supported partitions by providing a table of
++ * compatibility strings. This function finds a parser that advertises support
++ * for a passed value of "compatible".
++ */
++static struct mtd_part_parser *mtd_part_get_compatible_parser(const char *compat)
++{
++      struct mtd_part_parser *p, *ret = NULL;
++
++      spin_lock(&part_parser_lock);
++
++      list_for_each_entry(p, &part_parsers, list) {
++              const struct of_device_id *matches;
++
++              matches = p->of_match_table;
++              if (!matches)
++                      continue;
++
++              for (; matches->compatible[0]; matches++) {
++                      if (!strcmp(matches->compatible, compat) &&
++                          try_module_get(p->owner)) {
++                              ret = p;
++                              break;
++                      }
++              }
++
++              if (ret)
++                      break;
++      }
++
++      spin_unlock(&part_parser_lock);
++
++      return ret;
++}
++
++/**
+  * parse_mtd_partitions - parse MTD partitions
+  * @master: the master partition (describes whole MTD device)
+  * @types: names of partition parsers to try or %NULL
+@@ -911,8 +951,27 @@ int parse_mtd_partitions(struct mtd_info
+                        struct mtd_part_parser_data *data)
+ {
+       struct mtd_part_parser *parser;
++      struct device_node *np;
++      struct property *prop;
++      const char *compat;
+       int ret, err = 0;
++      np = of_get_child_by_name(mtd_get_of_node(master), "partitions");
++      of_property_for_each_string(np, "compatible", prop, compat) {
++              parser = mtd_part_get_compatible_parser(compat);
++              if (!parser)
++                      continue;
++              ret = mtd_part_do_parse(parser, master, pparts, data);
++              if (ret > 0) {
++                      of_node_put(np);
++                      return 0;
++              }
++              mtd_part_parser_put(parser);
++              if (ret < 0 && !err)
++                      err = ret;
++      }
++      of_node_put(np);
++
+       if (!types)
+               types = default_mtd_part_types;
+--- a/include/linux/mtd/partitions.h
++++ b/include/linux/mtd/partitions.h
+@@ -77,6 +77,7 @@ struct mtd_part_parser {
+       struct list_head list;
+       struct module *owner;
+       const char *name;
++      const struct of_device_id *of_match_table;
+       int (*parse_fn)(struct mtd_info *, const struct mtd_partition **,
+                       struct mtd_part_parser_data *);
+       void (*cleanup)(const struct mtd_partition *pparts, int nr_parts);
diff --git a/target/linux/generic/backport-4.9/067-v4.17-0002-mtd-ofpart-add-of_match_table-with-fixed-partitions.patch b/target/linux/generic/backport-4.9/067-v4.17-0002-mtd-ofpart-add-of_match_table-with-fixed-partitions.patch
new file mode 100644 (file)
index 0000000..2092cc2
--- /dev/null
@@ -0,0 +1,43 @@
+From 4ac9222778478a00c7fc9d347b7ed1e0e595120d Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Thu, 4 Jan 2018 08:05:34 +0100
+Subject: [PATCH] mtd: ofpart: add of_match_table with "fixed-partitions"
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This allows using this parser with any flash driver that takes care of
+setting of_node (using mtd_set_of_node helper) correctly. Up to now
+support for "fixed-partitions" DT compatibility string was working only
+with flash drivers that were specifying "ofpart" (manually or by letting
+mtd use the default set of parsers).
+
+This matches existing bindings documentation.
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Reviewed-by: Brian Norris <computersforpeace@gmail.com>
+Tested-by: Brian Norris <computersforpeace@gmail.com>
+Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
+---
+ drivers/mtd/ofpart.c | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+--- a/drivers/mtd/ofpart.c
++++ b/drivers/mtd/ofpart.c
+@@ -140,9 +140,16 @@ ofpart_none:
+       return ret;
+ }
++static const struct of_device_id parse_ofpart_match_table[] = {
++      { .compatible = "fixed-partitions" },
++      {},
++};
++MODULE_DEVICE_TABLE(of, parse_ofpart_match_table);
++
+ static struct mtd_part_parser ofpart_parser = {
+       .parse_fn = parse_ofpart_partitions,
+       .name = "ofpart",
++      .of_match_table = parse_ofpart_match_table,
+ };
+ static int parse_ofoldpart_partitions(struct mtd_info *master,
index 42985ef..f829631 100644 (file)
@@ -47,11 +47,9 @@ Will send separate patches to stable as this file got moved/renamed
  drivers/pci/dwc/pcie-designware-host.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)
 
-diff --git a/drivers/pci/dwc/pcie-designware-host.c b/drivers/pci/dwc/pcie-designware-host.c
-index bf558df5b7b3..2b5470173196 100644
 --- a/drivers/pci/dwc/pcie-designware-host.c
 +++ b/drivers/pci/dwc/pcie-designware-host.c
-@@ -616,7 +616,7 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
+@@ -607,7 +607,7 @@ void dw_pcie_setup_rc(struct pcie_port *
        /* setup bus numbers */
        val = dw_pcie_readl_dbi(pci, PCI_PRIMARY_BUS);
        val &= 0xff000000;