From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bh-25.webhostbox.net (bh-25.webhostbox.net [208.91.199.152]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 5233F1A02A5 for ; Thu, 6 Nov 2014 01:22:17 +1100 (AEDT) Received: from mailnull by bh-25.webhostbox.net with sa-checked (Exim 4.82) (envelope-from ) id 1Xm1TO-001PwG-7A for linuxppc-dev@lists.ozlabs.org; Wed, 05 Nov 2014 14:22:10 +0000 Date: Wed, 5 Nov 2014 06:21:49 -0800 From: Guenter Roeck To: Neelesh Gupta Subject: Re: [PATCH v2] hwmon: (ibmpowernv) Use platform 'id_table' to probe the device Message-ID: <20141105142149.GA23212@roeck-us.net> References: <20141105110848.6183.55611.stgit@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20141105110848.6183.55611.stgit@localhost.localdomain> Cc: benh@au1.ibm.com, michaele@au1.ibm.com, linux-kernel@vger.kernel.org, lm-sensors@lm-sensors.org, linuxppc-dev@lists.ozlabs.org, jdelvare@suse.de List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, Nov 05, 2014 at 04:45:14PM +0530, Neelesh Gupta wrote: > The current driver probe() function assumes the sensor device to be > alwary present and gets executed every time if the driver is loaded, > but the appropriate hardware could not be present. > > So, move the platform device creation as part of platform init code > and use the 'id_table' to check if the device present or not. > > Signed-off-by: Neelesh Gupta Looks good. We'll need an ack from one of the powerpc maintainers to proceed. Guenter > --- > > Changes in v2 > ============= > - Improve readability in error case if 'sensors' not found, also log > the using 'pr_err'. > > arch/powerpc/platforms/powernv/opal-sensor.c | 20 ++++++++ > drivers/hwmon/ibmpowernv.c | 67 +++++++------------------- > 2 files changed, 39 insertions(+), 48 deletions(-) > > diff --git a/arch/powerpc/platforms/powernv/opal-sensor.c b/arch/powerpc/platforms/powernv/opal-sensor.c > index 10271ad..4ab67ef 100644 > --- a/arch/powerpc/platforms/powernv/opal-sensor.c > +++ b/arch/powerpc/platforms/powernv/opal-sensor.c > @@ -20,7 +20,9 @@ > > #include > #include > +#include > #include > +#include > > static DEFINE_MUTEX(opal_sensor_mutex); > > @@ -64,3 +66,21 @@ out: > return ret; > } > EXPORT_SYMBOL_GPL(opal_get_sensor_data); > + > +static __init int opal_sensor_init(void) > +{ > + struct platform_device *pdev; > + struct device_node *sensor; > + > + sensor = of_find_node_by_path("/ibm,opal/sensors"); > + if (!sensor) { > + pr_err("Opal node 'sensors' not found\n"); > + return -ENODEV; > + } > + > + pdev = of_platform_device_create(sensor, "opal-sensor", NULL); > + of_node_put(sensor); > + > + return PTR_ERR_OR_ZERO(pdev); > +} > +machine_subsys_initcall(powernv, opal_sensor_init); > diff --git a/drivers/hwmon/ibmpowernv.c b/drivers/hwmon/ibmpowernv.c > index 6a30eee..c7577b8 100644 > --- a/drivers/hwmon/ibmpowernv.c > +++ b/drivers/hwmon/ibmpowernv.c > @@ -74,9 +74,6 @@ struct platform_data { > u32 sensors_count; /* Total count of sensors from each group */ > }; > > -/* Platform device representing all the ibmpowernv sensors */ > -static struct platform_device *pdevice; > - > static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr, > char *buf) > { > @@ -99,7 +96,7 @@ static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr, > return sprintf(buf, "%u\n", x); > } > > -static int __init get_sensor_index_attr(const char *name, u32 *index, > +static int get_sensor_index_attr(const char *name, u32 *index, > char *attr) > { > char *hash_pos = strchr(name, '#'); > @@ -136,7 +133,7 @@ static int __init get_sensor_index_attr(const char *name, u32 *index, > * which need to be mapped as fan2_input, temp1_max respectively before > * populating them inside hwmon device class. > */ > -static int __init create_hwmon_attr_name(struct device *dev, enum sensors type, > +static int create_hwmon_attr_name(struct device *dev, enum sensors type, > const char *node_name, > char *hwmon_attr_name) > { > @@ -172,7 +169,7 @@ static int __init create_hwmon_attr_name(struct device *dev, enum sensors type, > return 0; > } > > -static int __init populate_attr_groups(struct platform_device *pdev) > +static int populate_attr_groups(struct platform_device *pdev) > { > struct platform_data *pdata = platform_get_drvdata(pdev); > const struct attribute_group **pgroups = pdata->attr_groups; > @@ -180,11 +177,6 @@ static int __init populate_attr_groups(struct platform_device *pdev) > enum sensors type; > > opal = of_find_node_by_path("/ibm,opal/sensors"); > - if (!opal) { > - dev_dbg(&pdev->dev, "Opal node 'sensors' not found\n"); > - return -ENODEV; > - } > - > for_each_child_of_node(opal, np) { > if (np->name == NULL) > continue; > @@ -221,7 +213,7 @@ static int __init populate_attr_groups(struct platform_device *pdev) > * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max > * etc.. > */ > -static int __init create_device_attrs(struct platform_device *pdev) > +static int create_device_attrs(struct platform_device *pdev) > { > struct platform_data *pdata = platform_get_drvdata(pdev); > const struct attribute_group **pgroups = pdata->attr_groups; > @@ -280,7 +272,7 @@ exit_put_node: > return err; > } > > -static int __init ibmpowernv_probe(struct platform_device *pdev) > +static int ibmpowernv_probe(struct platform_device *pdev) > { > struct platform_data *pdata; > struct device *hwmon_dev; > @@ -309,52 +301,31 @@ static int __init ibmpowernv_probe(struct platform_device *pdev) > return PTR_ERR_OR_ZERO(hwmon_dev); > } > > +static const struct platform_device_id opal_sensor_driver_ids[] = { > + { > + .name = "opal-sensor", > + }, > + { } > +}; > +MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids); > + > static struct platform_driver ibmpowernv_driver = { > - .driver = { > - .owner = THIS_MODULE, > - .name = DRVNAME, > + .probe = ibmpowernv_probe, > + .id_table = opal_sensor_driver_ids, > + .driver = { > + .owner = THIS_MODULE, > + .name = DRVNAME, > }, > }; > > static int __init ibmpowernv_init(void) > { > - int err; > - > - pdevice = platform_device_alloc(DRVNAME, 0); > - if (!pdevice) { > - pr_err("Device allocation failed\n"); > - err = -ENOMEM; > - goto exit; > - } > - > - err = platform_device_add(pdevice); > - if (err) { > - pr_err("Device addition failed (%d)\n", err); > - goto exit_device_put; > - } > - > - err = platform_driver_probe(&ibmpowernv_driver, ibmpowernv_probe); > - if (err) { > - if (err != -ENODEV) > - pr_err("Platform driver probe failed (%d)\n", err); > - > - goto exit_device_del; > - } > - > - return 0; > - > -exit_device_del: > - platform_device_del(pdevice); > -exit_device_put: > - platform_device_put(pdevice); > -exit: > - return err; > + return platform_driver_register(&ibmpowernv_driver); > } > > static void __exit ibmpowernv_exit(void) > { > platform_driver_unregister(&ibmpowernv_driver); > - platform_device_unregister(pdevice); > } > > MODULE_AUTHOR("Neelesh Gupta "); >