Re: [RFC V2] bcm43xx-mac80211: Add TX power set file to debugfs

[Michael Buesch <mb@bu3sch.de>]

On Monday 06 August 2007 22:55:30 Larry Finger wrote:
> For testing purposes, this patch adds a file named "power_level" to the
> debugfs for bcm43xx-mac80211. If this file is read, it returns the current
> setting for the "Desired power level". Writing a number between 5 and 18
> will set that value as the new value for the desired power setting.
> 
> Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
> ---
> 
> Michael,
> 
> The error before is fixed in this version.
> 
> Larry
> 
> Index: wireless-dev/drivers/net/wireless/bcm43xx-mac80211/bcm43xx_debugfs.c
> ===================================================================
> --- wireless-dev.orig/drivers/net/wireless/bcm43xx-mac80211/bcm43xx_debugfs.c
> +++ wireless-dev/drivers/net/wireless/bcm43xx-mac80211/bcm43xx_debugfs.c
> @@ -151,6 +151,74 @@ out_unlock_bb:
>  	return res;
>  }
>  
> +static ssize_t power_read_file(struct file *file, char __user *userbuf,
> +			     size_t count, loff_t *ppos)
> +{
> +	struct bcm43xx_wldev *dev = file->private_data;
> +	const size_t len = ARRAY_SIZE(big_buffer);
> +	char *buf = big_buffer;
> +	size_t pos = 0;
> +	ssize_t res;
> +	unsigned long flags;
> +
> +	mutex_lock(&big_buffer_mutex);
> +	mutex_lock(&dev->wl->mutex);
> +	spin_lock_irqsave(&dev->wl->irq_lock, flags);
> +	if (bcm43xx_status(dev) < BCM43xx_STAT_STARTED) {
> +		fappend("Board not initialized.\n");
> +		goto out;
> +	}
> +	fappend("%d dBm\n",dev->phy.power_level);
> +
> +out:
> +	spin_unlock_irqrestore(&dev->wl->irq_lock, flags);
> +	mutex_unlock(&dev->wl->mutex);
> +	res = simple_read_from_buffer(userbuf, count, ppos, buf, pos);
> +	mutex_unlock(&big_buffer_mutex);
> +
> +	return res;
> +}
> +
> +static ssize_t power_write_file(struct file *file, const char __user *user_buf,
> +			      size_t count, loff_t *ppos)
> +{
> +	struct bcm43xx_wldev *dev = file->private_data;
> +	char *buf = big_buffer;
> +	ssize_t buf_size;
> +	ssize_t res;
> +	unsigned long flags;
> +	int power;
> +
> +	mutex_lock(&big_buffer_mutex);
> +	buf_size = min(count, ARRAY_SIZE(big_buffer) - 1);
> +	if (copy_from_user(buf, user_buf, buf_size)) {
> +	        res = -EFAULT;
> +		goto out_unlock_bb;
> +	}
> +	mutex_lock(&dev->wl->mutex);
> +	spin_lock_irqsave(&dev->wl->irq_lock, flags);
> +	if (bcm43xx_status(dev) < BCM43xx_STAT_STARTED) {
> +		bcmerr(dev->wl, "debugfs: Board not initialized.\n");
> +		res = -EFAULT;
> +		goto out_unlock;
> +	}
> +	if ((sscanf(buf, "%d", &power) != 1) || (power > 18 || power < 5)) {
> +		bcmerr(dev->wl, "debugfs: Invalid values for power level\n");
> +		res = -EINVAL;
> +		goto out_unlock;
> +	}
> +	dev->phy.power_level = power;
> +	res = buf_size;
> +
> +out_unlock:
> +	spin_unlock_irqrestore(&dev->wl->irq_lock, flags);
> +	mutex_unlock(&dev->wl->mutex);
> +out_unlock_bb:
> +	mutex_unlock(&big_buffer_mutex);
> +
> +	return res;
> +}
> +
>  static ssize_t txstat_read_file(struct file *file, char __user *userbuf,
>  				size_t count, loff_t *ppos)
>  {
> @@ -405,6 +473,12 @@ static struct file_operations restart_fo
>  	.open = open_file_generic,
>  };
>  
> +static struct file_operations power_fops = {
> +	.read = power_read_file,
> +	.write = power_write_file,
> +	.open = open_file_generic,
> +};
> +
>  
>  int bcm43xx_debug(struct bcm43xx_wldev *dev, enum bcm43xx_dyndbg feature)
>  {
> @@ -495,6 +569,11 @@ void bcm43xx_debugfs_add_device(struct b
>  	if (IS_ERR(e->dentry_restart))
>  		e->dentry_restart = NULL;
>  
> +	e->dentry_power = debugfs_create_file("power_level", 0600, e->subdir,
> +					     dev, &power_fops);
> +	if (IS_ERR(e->dentry_power))
> +		e->dentry_power = NULL;
> +
>  	bcm43xx_add_dynamic_debug(dev);
>  }
>  
> @@ -512,6 +591,7 @@ void bcm43xx_debugfs_remove_device(struc
>  	debugfs_remove(e->dentry_txstat);
>  	debugfs_remove(e->dentry_restart);
>  	debugfs_remove(e->dentry_txpower_g);
> +	debugfs_remove(e->dentry_power);
>  	debugfs_remove(e->subdir);
>  	kfree(e->txstatlog.log);
>  	kfree(e);
> Index: wireless-dev/drivers/net/wireless/bcm43xx-mac80211/bcm43xx_debugfs.h
> ===================================================================
> --- wireless-dev.orig/drivers/net/wireless/bcm43xx-mac80211/bcm43xx_debugfs.h
> +++ wireless-dev/drivers/net/wireless/bcm43xx-mac80211/bcm43xx_debugfs.h
> @@ -35,6 +35,7 @@ struct bcm43xx_dfsentry {
>  	struct dentry *dentry_txstat;
>  	struct dentry *dentry_txpower_g;
>  	struct dentry *dentry_restart;
> +	struct dentry *dentry_power;
>  
>  	struct bcm43xx_wldev *dev;
>  
> Index: wireless-dev/drivers/net/wireless/bcm43xx-mac80211/bcm43xx_main.c
> ===================================================================
> --- wireless-dev.orig/drivers/net/wireless/bcm43xx-mac80211/bcm43xx_main.c
> +++ wireless-dev/drivers/net/wireless/bcm43xx-mac80211/bcm43xx_main.c
> @@ -2763,7 +2763,8 @@ static int bcm43xx_dev_config(struct iee
>  
>  	/* Adjust the desired TX power level. */
>  	if (conf->power_level != 0) {
> -		if (conf->power_level != phy->power_level) {
> +		if (conf->power_level != phy->power_level &&
> +		    phy->power_level == 0) {
>  			phy->power_level = conf->power_level;
>  			bcm43xx_phy_xmitpower(dev);
>  		}

No, why do you poke with this at all.
This completely breaks power adjustment from mac80211.
Simply don't touch bcm43xx_dev_config :)

-- 
Greetings Michael.