[PATCH 3/4] nvmem: u-boot-env: use more nvmem subsystem helpers

Rafał Miłecki
2023-12-18T13:45:17Z

From: Rafał Miłecki <rafal@milecki.pl>

1. Use nvmem_dev_size() and nvmem_device_read() to make this driver less
mtd dependent
2. Use nvmem_add_one_cell() to simplify adding NVMEM cells

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
drivers/nvmem/u-boot-env.c | 79 +++++++++++++++++---------------------
1 file changed, 35 insertions(+), 44 deletions(-)

diff --git a/drivers/nvmem/u-boot-env.c b/drivers/nvmem/u-boot-env.c
index c4ae94af4af7..ab8c9bf63d99 100644
--- a/drivers/nvmem/u-boot-env.c
+++ b/drivers/nvmem/u-boot-env.c
@@ -23,13 +23,10 @@ enum u_boot_env_format {

struct u_boot_env {
struct device *dev;
+ struct nvmem_device *nvmem;
enum u_boot_env_format format;

struct mtd_info *mtd;
-
- /* Cells */
- struct nvmem_cell_info *cells;
- int ncells;
};

struct u_boot_env_image_single {
@@ -94,72 +91,69 @@ static int u_boot_env_read_post_process_ethaddr(void *context, const char *id, i
static int u_boot_env_add_cells(struct u_boot_env *priv, uint8_t *buf,
size_t data_offset, size_t data_len)
{
+ struct nvmem_device *nvmem = priv->nvmem;
struct device *dev = priv->dev;
char *data = buf + data_offset;
char *var, *value, *eq;
- int idx;
-
- priv->ncells = 0;
- for (var = data; var < data + data_len && *var; var += strlen(var) + 1)
- priv->ncells++;

- priv->cells = devm_kcalloc(dev, priv->ncells, sizeof(*priv->cells), GFP_KERNEL);
- if (!priv->cells)
- return -ENOMEM;
-
- for (var = data, idx = 0;
+ for (var = data;
var < data + data_len && *var;
- var = value + strlen(value) + 1, idx++) {
+ var = value + strlen(value) + 1) {
+ struct nvmem_cell_info info = {};
+
eq = strchr(var, '=');
if (!eq)
break;
*eq = '\0';
value = eq + 1;

- priv->cells[idx].name = devm_kstrdup(dev, var, GFP_KERNEL);
- if (!priv->cells[idx].name)
+ info.name = devm_kstrdup(dev, var, GFP_KERNEL);
+ if (!info.name)
return -ENOMEM;
- priv->cells[idx].offset = data_offset + value - data;
- priv->cells[idx].bytes = strlen(value);
- priv->cells[idx].np = of_get_child_by_name(dev->of_node, priv->cells[idx].name);
+ info.offset = data_offset + value - data;
+ info.bytes = strlen(value);
+ info.np = of_get_child_by_name(dev->of_node, info.name);
if (!strcmp(var, "ethaddr")) {
- priv->cells[idx].raw_len = strlen(value);
- priv->cells[idx].bytes = ETH_ALEN;
- priv->cells[idx].read_post_process = u_boot_env_read_post_process_ethaddr;
+ info.raw_len = strlen(value);
+ info.bytes = ETH_ALEN;
+ info.read_post_process = u_boot_env_read_post_process_ethaddr;
}
- }

- if (WARN_ON(idx != priv->ncells))
- priv->ncells = idx;
+ nvmem_add_one_cell(nvmem, &info);
+ }

return 0;
}

static int u_boot_env_parse(struct u_boot_env *priv)
{
+ struct nvmem_device *nvmem = priv->nvmem;
struct device *dev = priv->dev;
size_t crc32_data_offset;
size_t crc32_data_len;
size_t crc32_offset;
size_t data_offset;
size_t data_len;
+ size_t dev_size;
uint32_t crc32;
uint32_t calc;
- size_t bytes;
uint8_t *buf;
+ int bytes;
int err;

- buf = kcalloc(1, priv->mtd->size, GFP_KERNEL);
+ dev_size = nvmem_dev_size(nvmem);
+
+ buf = kcalloc(1, dev_size, GFP_KERNEL);
if (!buf) {
err = -ENOMEM;
goto err_out;
}

- err = mtd_read(priv->mtd, 0, priv->mtd->size, &bytes, buf);
- if ((err && !mtd_is_bitflip(err)) || bytes != priv->mtd->size) {
- dev_err(dev, "Failed to read from mtd: %d\n", err);
- goto err_kfree;
- }
+ bytes = nvmem_device_read(nvmem, 0, dev_size, buf);
+ if (bytes < 0)
+ return bytes;
+ else if (bytes != dev_size)
+ return -EIO;

switch (priv->format) {
case U_BOOT_FORMAT_SINGLE:
@@ -179,8 +173,8 @@ static int u_boot_env_parse(struct u_boot_env *priv)
break;
}
crc32 = le32_to_cpu(*(__le32 *)(buf + crc32_offset));
- crc32_data_len = priv->mtd->size - crc32_data_offset;
- data_len = priv->mtd->size - data_offset;
+ crc32_data_len = dev_size - crc32_data_offset;
+ data_len = dev_size - data_offset;

calc = crc32(~0, buf + crc32_data_offset, crc32_data_len) ^ ~0L;
if (calc != crc32) {
@@ -189,7 +183,7 @@ static int u_boot_env_parse(struct u_boot_env *priv)
goto err_kfree;
}

- buf[priv->mtd->size - 1] = '\0';
+ buf[dev_size - 1] = '\0';
err = u_boot_env_add_cells(priv, buf, data_offset, data_len);
if (err)
dev_err(dev, "Failed to add cells: %d\n", err);
@@ -209,7 +203,6 @@ static int u_boot_env_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct u_boot_env *priv;
- int err;

priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -224,17 +217,15 @@ static int u_boot_env_probe(struct platform_device *pdev)
return PTR_ERR(priv->mtd);
}

- err = u_boot_env_parse(priv);
- if (err)
- return err;
-
config.dev = dev;
- config.cells = priv->cells;
- config.ncells = priv->ncells;
config.priv = priv;
config.size = priv->mtd->size;

- return PTR_ERR_OR_ZERO(devm_nvmem_register(dev, &config));
+ priv->nvmem = devm_nvmem_register(dev, &config);
+ if (IS_ERR(priv->nvmem))
+ return PTR_ERR(priv->nvmem);
+
+ return u_boot_env_parse(priv);
}

static const struct of_device_id u_boot_env_of_match_table[] = {
--
2.35.3