Re: [PATCH 03/11] mfd: flexcard: add device attributes

[Lee Jones <lee.jones@linaro.org>]

On Wed, 25 Mar 2015, Holger Dengler wrote:

> From: Benedikt Spranger <b.spranger@linutronix.de>
> 
> Add device attributes for common flexcard information access. The
> attribiutes are read-only execpt "uid" (user ID register).
> The "uid" attribute can also be used to change the user-defined ID of a
> Flexcard.
> 
> Signed-off-by: Holger Dengler <dengler@linutronix.de>
> Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
> cc: Samuel Ortiz <sameo@linux.intel.com>
> cc: Lee Jones <lee.jones@linaro.org>
> ---
>  drivers/mfd/flexcard/Makefile   |   2 +-
>  drivers/mfd/flexcard/attr.c     | 215 ++++++++++++++++++++++++++++++++++++++++
>  drivers/mfd/flexcard/core.c     |  11 ++

I suggest this too should be part of the 'misc' driver and I wouldn't
split out attr fn()s into a separate file.

</review>

>  drivers/mfd/flexcard/flexcard.h |   7 ++
>  4 files changed, 234 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/mfd/flexcard/attr.c
>  create mode 100644 drivers/mfd/flexcard/flexcard.h
> 
> diff --git a/drivers/mfd/flexcard/Makefile b/drivers/mfd/flexcard/Makefile
> index 6606ebb..101000f 100644
> --- a/drivers/mfd/flexcard/Makefile
> +++ b/drivers/mfd/flexcard/Makefile
> @@ -1,2 +1,2 @@
>  obj-$(CONFIG_MFD_FLEXCARD)	+= flexcard.o
> -flexcard-objs			:= core.o
> +flexcard-objs			:= core.o attr.o
> diff --git a/drivers/mfd/flexcard/attr.c b/drivers/mfd/flexcard/attr.c
> new file mode 100644
> index 0000000..c91c884
> --- /dev/null
> +++ b/drivers/mfd/flexcard/attr.c
> @@ -0,0 +1,215 @@
> +/*
> + * Eberspaecher Flexcard PMC II Carrier Board PCI Driver - device attributes
> + *
> + * Copyright (c) 2014,2015 Linutronix GmbH
> + * Author: Holger Dengler
> + *         Benedikt Spranger
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License version 2 as published
> + * by the Free Software Foundation.
> + */
> +#include <linux/device.h>
> +#include <linux/flexcard.h>
> +#include <linux/kref.h>
> +#include <linux/miscdevice.h>
> +#include <linux/pci.h>
> +#include <linux/mfd/flexcard.h>
> +
> +static ssize_t fw_version_show(struct device *dev,
> +			       struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%02x.%02x.%02x\n", priv->conf->fc_fw_ver.maj,
> +		       priv->conf->fc_fw_ver.min, priv->conf->fc_fw_ver.dev);
> +}
> +static DEVICE_ATTR_RO(fw_version);
> +
> +static ssize_t hw_version_show(struct device *dev,
> +			       struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%02x.%02x.%02x\n", priv->conf->fc_hw_ver.maj,
> +		       priv->conf->fc_hw_ver.min, priv->conf->fc_hw_ver.dev);
> +}
> +static DEVICE_ATTR_RO(hw_version);
> +
> +static ssize_t serialno_show(struct device *dev,
> +			     struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%lld\n", priv->conf->fc_sn);
> +}
> +static DEVICE_ATTR_RO(serialno);
> +
> +static ssize_t tiny_stat_show(struct device *dev,
> +			      struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "0x%x\n", priv->conf->tiny_stat);
> +}
> +static DEVICE_ATTR_RO(tiny_stat);
> +
> +static ssize_t can_dat_show(struct device *dev,
> +			    struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", priv->conf->can_dat_cnt);
> +}
> +static DEVICE_ATTR_RO(can_dat);
> +
> +static ssize_t can_err_show(struct device *dev,
> +			    struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", priv->conf->can_err_cnt);
> +}
> +static DEVICE_ATTR_RO(can_err);
> +
> +static ssize_t fc_data_show(struct device *dev,
> +			    struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", priv->conf->fc_data_cnt);
> +}
> +static DEVICE_ATTR_RO(fc_data);
> +
> +static ssize_t fr_rx_show(struct device *dev,
> +			    struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", priv->conf->fr_rx_cnt);
> +}
> +static DEVICE_ATTR_RO(fr_rx);
> +
> +static ssize_t fr_tx_show(struct device *dev,
> +			    struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", priv->conf->fr_tx_cnt);
> +}
> +static DEVICE_ATTR_RO(fr_tx);
> +
> +static ssize_t nmv_show(struct device *dev,
> +			struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", priv->conf->nmv_cnt);
> +}
> +static DEVICE_ATTR_RO(nmv);
> +
> +static ssize_t info_show(struct device *dev,
> +			 struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", priv->conf->info_cnt);
> +}
> +static DEVICE_ATTR_RO(info);
> +
> +static ssize_t stat_trg_show(struct device *dev,
> +			     struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", priv->conf->stat_trg_cnt);
> +}
> +static DEVICE_ATTR_RO(stat_trg);
> +
> +static ssize_t nf_show(struct device *dev,
> +		       struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", priv->conf->nf_cnt);
> +}
> +static DEVICE_ATTR_RO(nf);
> +
> +static ssize_t uid_store(struct device *dev, struct device_attribute *attr,
> +			 const char *buf, size_t count)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +	unsigned long uid;
> +	int ret;
> +
> +	ret = kstrtou32(buf, 0, &uid);
> +	if (ret)
> +		return ret;
> +
> +	priv->conf->fc_uid = uid;
> +	return count;
> +}
> +
> +static ssize_t uid_show(struct device *dev,
> +			struct device_attribute *attr, char *buf)
> +{
> +	struct pci_dev *pdev = to_pci_dev(dev->parent);
> +	struct flexcard_device *priv = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%u\n", priv->conf->fc_uid);
> +}
> +static DEVICE_ATTR(uid, S_IRUGO|S_IWUSR, uid_show, uid_store);
> +
> +static struct attribute *flexcard_misc_dev_attrs[] = {
> +	&dev_attr_fw_version.attr,
> +	&dev_attr_hw_version.attr,
> +	&dev_attr_serialno.attr,
> +	&dev_attr_tiny_stat.attr,
> +	&dev_attr_can_dat.attr,
> +	&dev_attr_can_err.attr,
> +	&dev_attr_fc_data.attr,
> +	&dev_attr_fr_rx.attr,
> +	&dev_attr_fr_tx.attr,
> +	&dev_attr_nmv.attr,
> +	&dev_attr_info.attr,
> +	&dev_attr_stat_trg.attr,
> +	&dev_attr_nf.attr,
> +	&dev_attr_uid.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group flexcard_misc_dev_group = {
> +	.attrs = flexcard_misc_dev_attrs,
> +};
> +
> +int flexcard_misc_add_attrs(struct device *dev)
> +{
> +	int ret;
> +
> +	ret = sysfs_create_group(&dev->kobj,
> +				 &flexcard_misc_dev_group);
> +
> +	if (ret)
> +		dev_err(dev, "failed to create sysfs attributes: %d\n", ret);
> +
> +	return ret;
> +}
> +
> +void flexcard_misc_del_attrs(struct device *dev)
> +{
> +	sysfs_remove_group(&dev->kobj, &flexcard_misc_dev_group);
> +}
> diff --git a/drivers/mfd/flexcard/core.c b/drivers/mfd/flexcard/core.c
> index 1e7fb0f..6477019 100644
> --- a/drivers/mfd/flexcard/core.c
> +++ b/drivers/mfd/flexcard/core.c
> @@ -22,6 +22,8 @@
>  #include <linux/mfd/core.h>
>  #include <linux/mfd/flexcard.h>
>  
> +#include "flexcard.h"
> +
>  static DEFINE_IDA(flexcard_ida);
>  
>  static const char drv_name[] = "flexcard";
> @@ -237,6 +239,12 @@ static int flexcard_probe(struct pci_dev *pdev,
>  		goto out_remove;
>  	}
>  
> +	ret = flexcard_misc_add_attrs(priv->dev.this_device);
> +	if (ret) {
> +		dev_err(&pdev->dev, "unable to register miscdevice: %d\n", ret);
> +		goto out_deregister;
> +	}
> +
>  	dev_info(&pdev->dev, "HW %02x.%02x.%02x FW %02x.%02x.%02x\n",
>  		 priv->conf->fc_hw_ver.maj, priv->conf->fc_hw_ver.min,
>  		 priv->conf->fc_hw_ver.dev, priv->conf->fc_fw_ver.maj,
> @@ -244,6 +252,8 @@ static int flexcard_probe(struct pci_dev *pdev,
>  
>  	return 0;
>  
> +out_deregister:
> +	misc_deregister(&priv->dev);
>  out_remove:
>  	mfd_remove_devices(&pdev->dev);
>  out_unmap:
> @@ -264,6 +274,7 @@ static void flexcard_remove(struct pci_dev *pdev)
>  {
>  	struct flexcard_device *priv = pci_get_drvdata(pdev);
>  
> +	flexcard_misc_del_attrs(priv->dev.this_device);
>  	misc_deregister(&priv->dev);
>  	mfd_remove_devices(&pdev->dev);
>  	iounmap(priv->conf);
> diff --git a/drivers/mfd/flexcard/flexcard.h b/drivers/mfd/flexcard/flexcard.h
> new file mode 100644
> index 0000000..1fe451e
> --- /dev/null
> +++ b/drivers/mfd/flexcard/flexcard.h
> @@ -0,0 +1,7 @@
> +#ifndef __FLEXCARD_H
> +#define  __FLEXCARD_H
> +
> +int flexcard_misc_add_attrs(struct device *dev);
> +void flexcard_misc_del_attrs(struct device *dev);
> +
> +#endif /* __FLEXCARD_H */

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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