2014-01-23 19:26:12

by Curt Brune

Subject: [PATCH v2 2/2] Add at24 based EEPROMs to the eeprom_dev hardware class

During device instantiation have the at24 driver add the new device to
the eeprom_dev hardware class. The functionality is enabled by
CONFIG_EEPROM_CLASS.

Signed-off-by: Curt Brune <[email protected]>
---
drivers/misc/eeprom/at24.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index d87f77f..07782ea 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -22,10 +22,14 @@
#include <linux/jiffies.h>
#include <linux/of.h>
#include <linux/i2c.h>
#include <linux/platform_data/at24.h>

+#ifdef CONFIG_EEPROM_CLASS
+#include <linux/eeprom_class.h>
+#endif
+
/*
* I2C EEPROMs from most vendors are inexpensive and mostly interchangeable.
* Differences between different vendor product lines (like Atmel AT24C or
* MicroChip 24LC, etc) won't much matter for typical read/write access.
* There are also I2C RAM chips, likewise interchangeable. One example
@@ -66,10 +70,13 @@ struct at24_data {

u8 *writebuf;
unsigned write_max;
unsigned num_addresses;

+#ifdef CONFIG_EEPROM_CLASS
+ struct device *eeprom_dev;
+#endif
/*
* Some chips tie up multiple I2C addresses; dummy devices reserve
* them for us, and we'll use them with SMBus calls.
*/
struct i2c_client *client[];
@@ -619,10 +626,19 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)

err = sysfs_create_bin_file(&client->dev.kobj, &at24->bin);
if (err)
goto err_clients;

+#ifdef CONFIG_EEPROM_CLASS
+ at24->eeprom_dev = eeprom_device_register(&client->dev);
+ if (IS_ERR(at24->eeprom_dev)) {
+ dev_err(&client->dev, "error registering eeprom device.\n");
+ err = PTR_ERR(at24->eeprom_dev);
+ goto err_clients;
+ }
+#endif
+
i2c_set_clientdata(client, at24);

dev_info(&client->dev, "%zu byte %s EEPROM, %s, %u bytes/write\n",
at24->bin.size, client->name,
writable ? "writable" : "read-only", at24->write_max);
@@ -656,10 +672,14 @@ static int at24_remove(struct i2c_client *client)
sysfs_remove_bin_file(&client->dev.kobj, &at24->bin);

for (i = 1; i < at24->num_addresses; i++)
i2c_unregister_device(at24->client[i]);

+#ifdef CONFIG_EEPROM_CLASS
+ eeprom_device_unregister(at24->eeprom_dev);
+#endif
+
return 0;
}

/*-------------------------------------------------------------------------*/

--
1.7.10.4

2014-01-26 12:46:00

by Igor Grinberg

Subject: Re: [PATCH v2 2/2] Add at24 based EEPROMs to the eeprom_dev hardware class

Hi Curt,

On 01/23/14 21:16, Curt Brune wrote:
> During device instantiation have the at24 driver add the new device to
> the eeprom_dev hardware class. The functionality is enabled by
> CONFIG_EEPROM_CLASS.
>
> Signed-off-by: Curt Brune <[email protected]>
> ---
> drivers/misc/eeprom/at24.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index d87f77f..07782ea 100644
> --- a/drivers/misc/eeprom/at24.c
> +++ b/drivers/misc/eeprom/at24.c
> @@ -22,10 +22,14 @@
> #include <linux/jiffies.h>
> #include <linux/of.h>
> #include <linux/i2c.h>
> #include <linux/platform_data/at24.h>
>
> +#ifdef CONFIG_EEPROM_CLASS
> +#include <linux/eeprom_class.h>
> +#endif

I would recommend moving the "ifdeffery" into the eeprom_class.h
and leave the users (in this case the at24.c) clean.

> +
> /*
> * I2C EEPROMs from most vendors are inexpensive and mostly interchangeable.
> * Differences between different vendor product lines (like Atmel AT24C or
> * MicroChip 24LC, etc) won't much matter for typical read/write access.
> * There are also I2C RAM chips, likewise interchangeable. One example
> @@ -66,10 +70,13 @@ struct at24_data {
>
> u8 *writebuf;
> unsigned write_max;
> unsigned num_addresses;
>
> +#ifdef CONFIG_EEPROM_CLASS
> + struct device *eeprom_dev;
> +#endif

Same here, this is just a pointer, so I don't think anyone has
a problem having it even if eeprom class is not selected.

> /*
> * Some chips tie up multiple I2C addresses; dummy devices reserve
> * them for us, and we'll use them with SMBus calls.
> */
> struct i2c_client *client[];
> @@ -619,10 +626,19 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
>
> err = sysfs_create_bin_file(&client->dev.kobj, &at24->bin);
> if (err)
> goto err_clients;
>
> +#ifdef CONFIG_EEPROM_CLASS
> + at24->eeprom_dev = eeprom_device_register(&client->dev);
> + if (IS_ERR(at24->eeprom_dev)) {
> + dev_err(&client->dev, "error registering eeprom device.\n");
> + err = PTR_ERR(at24->eeprom_dev);
> + goto err_clients;
> + }
> +#endif

stub the eeprom_device_register() out in eeprom_class.h
for !CONFIG_EEPROM_CLASS case

> +
> i2c_set_clientdata(client, at24);
>
> dev_info(&client->dev, "%zu byte %s EEPROM, %s, %u bytes/write\n",
> at24->bin.size, client->name,
> writable ? "writable" : "read-only", at24->write_max);
> @@ -656,10 +672,14 @@ static int at24_remove(struct i2c_client *client)
> sysfs_remove_bin_file(&client->dev.kobj, &at24->bin);
>
> for (i = 1; i < at24->num_addresses; i++)
> i2c_unregister_device(at24->client[i]);
>
> +#ifdef CONFIG_EEPROM_CLASS
> + eeprom_device_unregister(at24->eeprom_dev);
> +#endif

same here.

> +
> return 0;
> }
>
> /*-------------------------------------------------------------------------*/
>
>

--
Regards,
Igor.