realtek: stc8: use flexible array member

Simplifies allocation. Also addeed __counted_by for extra runtime
analysis.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/22506
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

diff --git a/target/linux/realtek/patches-6.12/809-add-hasivo-stc8-mfd.patch b/target/linux/realtek/patches-6.12/809-add-hasivo-stc8-mfd.patch
index 81be5cbc2dc91089f5a8c7937bde978d3992fd2b..7c865eb4d19aac2af7e92c6d44e714687c3ae1e8 100644 (file)
--- a/target/linux/realtek/patches-6.12/809-add-hasivo-stc8-mfd.patch
+++ b/target/linux/realtek/patches-6.12/809-add-hasivo-stc8-mfd.patch
@@ -74,7 +74,7 @@ Signed-off-by: Bevan Weiss <bevan.weiss@gmail.com>
 +    defaults: 0x40
 +    required: false
 +
-+  hasivo,execute-bit-regs:
++  hasivo,execute-bit-registers:
 +    description: >
 +      Array of registers for which the execute-bit mask should be
 +      applied.  Writes to other registers will not have the execute-bit mask
@@ -160,7 +160,7 @@ Signed-off-by: Bevan Weiss <bevan.weiss@gmail.com>
 +obj-$(CONFIG_MFD_HASIVO_STC8) += hasivo-stc8-mfd.o
 --- /dev/null
 +++ b/drivers/mfd/hasivo-stc8-mfd.c
-@@ -0,0 +1,182 @@
+@@ -0,0 +1,169 @@
 +// SPDX-License-Identifier: GPL-2.0-only
 +/*
 + * Hasivo STC8 MFD driver with configurable write ORing for execute bit
@@ -180,8 +180,8 @@ Signed-off-by: Bevan Weiss <bevan.weiss@gmail.com>
 +      struct regmap *parent_regmap;
 +      struct regmap *child_regmap;
 +      u32 exec_bit;
-+      u32 *exec_regs;
 +      size_t num_exec_regs;
++      u32 exec_regs[] __counted_by(num_exec_regs);
 +};
 +
 +/* Check if register requires execute bit */
@@ -232,26 +232,30 @@ Signed-off-by: Bevan Weiss <bevan.weiss@gmail.com>
 +      .reg_write = stc8_child_reg_write,
 +};
 +
-+static int stc8_parse_dt(struct stc8_mfd *mfd, struct device_node *np)
++static int stc8_i2c_probe(struct i2c_client *client)
 +{
-+      int ret, count;
++      struct device_node *np = client->dev.of_node;
++      struct stc8_mfd *mfd;
++      u32 exec_bit;
++      int count;
++      int ret;
 +
 +      /* Get execute bit value (default 0x40) */
-+      mfd->exec_bit = 0x40;
-+      ret = of_property_read_u32(np, "hasivo,execute-bit", &mfd->exec_bit);
++      if (of_property_read_u32(np, "hasivo,execute-bit", &exec_bit))
++              exec_bit = 0x40;
 +
 +      /* Get count of execute registers */
 +      count = of_property_count_u32_elems(np, "hasivo,execute-bit-registers");
-+      if (count <= 0) {
-+              mfd->num_exec_regs = 0;
-+      }
-+      else {
-+              mfd->num_exec_regs = count;
-+              mfd->exec_regs = devm_kcalloc(mfd->dev, count, sizeof(u32),
-+                                           GFP_KERNEL);
-+              if (!mfd->exec_regs)
-+                      return -ENOMEM;
++      if (count < 0)
++              count = 0;
++
++      mfd = devm_kzalloc(&client->dev, struct_size(mfd, exec_regs, count), GFP_KERNEL);
++      if (!mfd)
++              return -ENOMEM;
 +
++      mfd->num_exec_regs = count;
++      mfd->dev = &client->dev;
++      if (count > 0) {
 +              ret = of_property_read_u32_array(np, "hasivo,execute-bit-registers",
 +                                              mfd->exec_regs, count);
 +              if (ret) {
@@ -260,31 +264,14 @@ Signed-off-by: Bevan Weiss <bevan.weiss@gmail.com>
 +              }
 +      }
 +
++      mfd->exec_bit = exec_bit;
 +      dev_info(mfd->dev, "execute-bit=0x%02x, %zu execute-bit-registers\n",
 +               mfd->exec_bit, mfd->num_exec_regs);
 +
-+      return 0;
-+}
-+
-+static int stc8_i2c_probe(struct i2c_client *client)
-+{
-+      struct stc8_mfd *mfd;
-+      int ret;
-+
-+      dev_dbg(&client->dev, "Hasivo STC8 MFD driver probed started\n");
-+
-+      mfd = devm_kzalloc(&client->dev, sizeof(struct stc8_mfd), GFP_KERNEL);
-+      if (!mfd)
-+              return -ENOMEM;
++      dev_dbg(mfd->dev, "Hasivo STC8 MFD driver probed started\n");
 +
-+      mfd->dev = &client->dev;
 +      i2c_set_clientdata(client, mfd);
 +
-+      /* Parse device tree properties */
-+      ret = stc8_parse_dt(mfd, mfd->dev->of_node);
-+      if (ret)
-+              return ret;
-+
 +      /* Create parent regmap for direct I2C access */
 +      mfd->parent_regmap = devm_regmap_init_i2c(client,
 +                                                 &stc8_parent_regmap_config);