RE: [patch] Disable PMBus status check for DPS400 PSU controller

Vadim Pasternak
2016-07-21T14:08:59Z

> -----Original Message-----
> From: Guenter Roeck [mailto:linux@roeck-us.net]
> Sent: Thursday, July 21, 2016 4:42 PM
> To: Vadim Pasternak <vadimp@mellanox.com>
> Cc: jdelvare@suse.com; linux-hwmon@vger.kernel.org; linux-
> kernel@vger.kernel.org; jiri@resnulli.us
> Subject: Re: [patch] Disable PMBus status check for DPS400 PSU controller
>

Hi Guenter,

Thank you very much for your reply.

> Hi Vadim,
>
> On 07/21/2016 07:55 AM, Vadim Pasternak wrote:
> > pmbus/dps400: disable PMBus status check through platform data
> > structure to provide support for PSU DPS-460, DPS-800 from Delta
> > Electronics, INC and for
> > SGD009 from Acbel Polytech, INC.
> > These devices do not support the STATUS_CML register, and reports
> > communication error in response to this command.
> > For this reason for these controllers, the status register check is disabled.
> >
>
> The subject should be "hwmon: (pmbus) Add explicit support for DPS-460, DPS-
> 800, and SGD009", followed by something like
>
> "Provide support for PSU DPS-460, DPS-800 from Delta Electronics, INC and for
> SGD009 from Acbel Polytech, INC.
> These devices do not support the STATUS_CML register and report a
> communication error in response to this command. For this reason, the status
> register check is disabled for these controllers."
>
> > Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
> >
> Unnecessary blank line
>
> > Reviewed-by: Jiri Pirko <jiri@mellanox.com>
> > ---
> > drivers/hwmon/pmbus/pmbus.c | 16 ++++++++++++++++
> > drivers/hwmon/pmbus/pmbus_core.c | 3 +++
> > 2 files changed, 19 insertions(+)
> >
> > diff --git a/drivers/hwmon/pmbus/pmbus.c b/drivers/hwmon/pmbus/pmbus.c
> > index 0a74991..44c736a 100644
> > --- a/drivers/hwmon/pmbus/pmbus.c
> > +++ b/drivers/hwmon/pmbus/pmbus.c
> > @@ -25,6 +25,7 @@
> > #include <linux/slab.h>
> > #include <linux/mutex.h>
> > #include <linux/i2c.h>
> > +#include <linux/i2c/pmbus.h>
> > #include "pmbus.h"
> >
> > /*
> > @@ -167,14 +168,26 @@ static int pmbus_probe(struct i2c_client *client,
> > const struct i2c_device_id *id)
> > {
> > struct pmbus_driver_info *info;
> > + struct pmbus_platform_data *pdata = NULL;
> > + struct device *dev = &client->dev;
> >
> > info = devm_kzalloc(&client->dev, sizeof(struct pmbus_driver_info),
> > GFP_KERNEL);
> > if (!info)
> > return -ENOMEM;
> > + if (!strcmp(id->name, "dps460") || !strcmp(id->name, "dps460") ||
>
> Should the second string be dps800 ?
>
> > + !strcmp(id->name, "sgd009")) {
> > + pdata = kzalloc(sizeof(struct pmbus_platform_data),
> GFP_KERNEL);
>
> Please use devm_kzalloc().
>
> > + if (!pdata) {
> > + kfree(info);
>
> info was allocated with devm_kzalloc() and thus does not need kfree (besides, if
> at all, it would have to be devm_kfree).
>
> > + return -ENOMEM;
> > + }
> > + pdata->flags = PMBUS_SKIP_STATUS_CHECK;
> > + }
> >
> > info->pages = id->driver_data;
> > info->identify = pmbus_identify;
> > + dev->platform_data = pdata;
> >
> > return pmbus_do_probe(client, id, info);
> > }
> > @@ -199,6 +212,9 @@ static const struct i2c_device_id pmbus_id[] = {
> > {"tps544c20", 1},
> > {"tps544c25", 1},
> > {"udt020", 1},
> > + {"dps460", 1},
> > + {"dps800", 1},
> > + {"sgd009", 1},
>
> Please list in alphabetic order.
>
> > {}
> > };
> >
> > diff --git a/drivers/hwmon/pmbus/pmbus_core.c
> > b/drivers/hwmon/pmbus/pmbus_core.c
> > index ba59eae..3d98070 100644
> > --- a/drivers/hwmon/pmbus/pmbus_core.c
> > +++ b/drivers/hwmon/pmbus/pmbus_core.c
> > @@ -1931,8 +1931,11 @@ EXPORT_SYMBOL_GPL(pmbus_do_probe);
> > int pmbus_do_remove(struct i2c_client *client)
> > {
> > struct pmbus_data *data = i2c_get_clientdata(client);
> > + const struct pmbus_platform_data *pdata =
> > + dev_get_platdata(&client->dev);
> > hwmon_device_unregister(data->hwmon_dev);
> > kfree(data->group.attrs);
> > + kfree(pdata);

So, if I use in allocation
pdata = devm_kzalloc(&client->dev,
sizeof(struct pmbus_platform_data),
GFP_KERNEL);
I also can drop the above three lines, right?

> > return 0;
> > }
> > EXPORT_SYMBOL_GPL(pmbus_do_remove);
> >