[PATCH v2] regmap: spi: Set regmap max raw r/w from max_transfer_size

From: Lucas Tanure
Date: Mon Sep 13 2021 - 09:01:14 EST


Set regmap raw read/write from spi max_transfer_size
so regmap_raw_read/write can split the access into chunks

Signed-off-by: Lucas Tanure <tanureal@xxxxxxxxxxxxxxxxxxxxx>
---

Changes v2:
Sent as single patch

drivers/base/regmap/regmap-spi.c | 36 ++++++++++++++++++++++++++++----
1 file changed, 32 insertions(+), 4 deletions(-)

diff --git a/drivers/base/regmap/regmap-spi.c b/drivers/base/regmap/regmap-spi.c
index c1894e93c3788..0e6552e57ecf9 100644
--- a/drivers/base/regmap/regmap-spi.c
+++ b/drivers/base/regmap/regmap-spi.c
@@ -109,13 +109,37 @@ static const struct regmap_bus regmap_spi = {
.val_format_endian_default = REGMAP_ENDIAN_BIG,
};

+static const struct regmap_bus *regmap_get_spi_bus(struct spi_device *spi,
+ const struct regmap_config *config)
+{
+ struct spi_master *master = spi->master;
+ struct regmap_bus *bus = NULL;
+ size_t max_size = spi_max_transfer_size(spi);
+
+ if (max_size != SIZE_MAX) {
+ bus = kmemdup(&regmap_spi, sizeof(*bus), GFP_KERNEL);
+ if (!bus)
+ return ERR_PTR(-ENOMEM);
+ bus->free_on_exit = true;
+ bus->max_raw_read = max_size;
+ bus->max_raw_write = max_size;
+ return bus;
+ }
+
+ return &regmap_spi;
+}
+
struct regmap *__regmap_init_spi(struct spi_device *spi,
const struct regmap_config *config,
struct lock_class_key *lock_key,
const char *lock_name)
{
- return __regmap_init(&spi->dev, &regmap_spi, &spi->dev, config,
- lock_key, lock_name);
+ const struct regmap_bus *bus = regmap_get_spi_bus(spi, config);
+
+ if (IS_ERR(bus))
+ return ERR_CAST(bus);
+
+ return __regmap_init(&spi->dev, bus, &spi->dev, config, lock_key, lock_name);
}
EXPORT_SYMBOL_GPL(__regmap_init_spi);

@@ -124,8 +148,12 @@ struct regmap *__devm_regmap_init_spi(struct spi_device *spi,
struct lock_class_key *lock_key,
const char *lock_name)
{
- return __devm_regmap_init(&spi->dev, &regmap_spi, &spi->dev, config,
- lock_key, lock_name);
+ const struct regmap_bus *bus = regmap_get_spi_bus(spi, config);
+
+ if (IS_ERR(bus))
+ return ERR_CAST(bus);
+
+ return __devm_regmap_init(&spi->dev, bus, &spi->dev, config, lock_key, lock_name);
}
EXPORT_SYMBOL_GPL(__devm_regmap_init_spi);

--
2.33.0