[PATCH v5 2/4] pmbus: core: add helpers for byte write and read modify write

atull
2014-10-02T18:44:37Z

From: Alan Tull <atull@opensource.altera.com>

Add two helper functions:
* pmbus_write_byte_data = paged byte write
* pmbus_update_byte_data = paged byte read/modify/write

Signed-off-by: Alan Tull <atull@opensource.altera.com>
---
v2: add prototypes for the two new functions
---
drivers/hwmon/pmbus/pmbus.h | 4 ++++
drivers/hwmon/pmbus/pmbus_core.c | 31 +++++++++++++++++++++++++++++++
2 files changed, 35 insertions(+)

diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h
index fa9beb3..3ae79a7 100644
--- a/drivers/hwmon/pmbus/pmbus.h
+++ b/drivers/hwmon/pmbus/pmbus.h
@@ -375,6 +375,10 @@ int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg);
int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word);
int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg);
int pmbus_write_byte(struct i2c_client *client, int page, u8 value);
+int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg,
+ u8 value);
+int pmbus_update_byte_data(struct i2c_client *client, int page, u8 reg,
+ u8 mask, u8 value);
void pmbus_clear_faults(struct i2c_client *client);
bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg);
bool pmbus_check_word_register(struct i2c_client *client, int page, int reg);
diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 291d11f..d6c3701 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -253,6 +253,37 @@ int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg)
}
EXPORT_SYMBOL_GPL(pmbus_read_byte_data);

+int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, u8 value)
+{
+ int rv;
+
+ rv = pmbus_set_page(client, page);
+ if (rv < 0)
+ return rv;
+
+ return i2c_smbus_write_byte_data(client, reg, value);
+}
+EXPORT_SYMBOL_GPL(pmbus_write_byte_data);
+
+int pmbus_update_byte_data(struct i2c_client *client, int page, u8 reg,
+ u8 mask, u8 value)
+{
+ unsigned int tmp;
+ int rv;
+
+ rv = pmbus_read_byte_data(client, page, reg);
+ if (rv < 0)
+ return rv;
+
+ tmp = (rv & ~mask) | (value & mask);
+
+ if (tmp != rv)
+ rv = pmbus_write_byte_data(client, page, reg, tmp);
+
+ return rv;
+}
+EXPORT_SYMBOL_GPL(pmbus_update_byte_data);
+
/*
* _pmbus_read_byte_data() is similar to pmbus_read_byte_data(), but checks if
* a device specific mapping function exists and calls it if necessary.
--
1.7.9.5