i2c: slave-eeprom: Make it possible to pre-load eeprom data

If the slave eeprom has a "firmware-name" in devicetree, then pre-load
the data in the eeprom with this file. Otherwise we init the eeprom with
0xFF.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Signed-off-by: Björn Ardö <bjorn.ardo@axis.com>
[wsa: some cosmetic changes]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Björn Ardö 2020-04-24 13:30:36 +02:00 committed by Wolfram Sang
parent e42688ed5c
commit e804f0a78e

View File

@ -18,6 +18,7 @@
*/ */
#include <linux/bitfield.h> #include <linux/bitfield.h>
#include <linux/firmware.h>
#include <linux/i2c.h> #include <linux/i2c.h>
#include <linux/init.h> #include <linux/init.h>
#include <linux/module.h> #include <linux/module.h>
@ -120,6 +121,26 @@ static ssize_t i2c_slave_eeprom_bin_write(struct file *filp, struct kobject *kob
return count; return count;
} }
static int i2c_slave_init_eeprom_data(struct eeprom_data *eeprom, struct i2c_client *client,
unsigned int size)
{
const struct firmware *fw;
const char *eeprom_data;
int ret = device_property_read_string(&client->dev, "firmware-name", &eeprom_data);
if (!ret) {
ret = request_firmware_into_buf(&fw, eeprom_data, &client->dev,
eeprom->buffer, size);
if (ret)
return ret;
release_firmware(fw);
} else {
/* An empty eeprom typically has all bits set to 1 */
memset(eeprom->buffer, 0xff, size);
}
return 0;
}
static int i2c_slave_eeprom_probe(struct i2c_client *client, const struct i2c_device_id *id) static int i2c_slave_eeprom_probe(struct i2c_client *client, const struct i2c_device_id *id)
{ {
struct eeprom_data *eeprom; struct eeprom_data *eeprom;
@ -138,6 +159,10 @@ static int i2c_slave_eeprom_probe(struct i2c_client *client, const struct i2c_de
spin_lock_init(&eeprom->buffer_lock); spin_lock_init(&eeprom->buffer_lock);
i2c_set_clientdata(client, eeprom); i2c_set_clientdata(client, eeprom);
ret = i2c_slave_init_eeprom_data(eeprom, client, size);
if (ret)
return ret;
sysfs_bin_attr_init(&eeprom->bin); sysfs_bin_attr_init(&eeprom->bin);
eeprom->bin.attr.name = "slave-eeprom"; eeprom->bin.attr.name = "slave-eeprom";
eeprom->bin.attr.mode = S_IRUSR | S_IWUSR; eeprom->bin.attr.mode = S_IRUSR | S_IWUSR;