Re: [PATCH v2 1/1] platform/x86/intel_pmc_core: Convert to DEFINE_DEBUGFS_ATTRIBUTE

[Rajneesh Bhardwaj]

On Mon, Jul 04, 2016 at 03:39:48PM +0300, Andy Shevchenko wrote:
> This patch does the following:
> - refactors code to use recently introduced DEFINE_DEBUGFS_ATTRIBUTE() macro
> - makes absence of DEBUG_FS non-fatal error
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

Reviewed-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@xxxxxxxxx>

Compiled & tested this on Ubuntu 16.04.
Kernel: 4.7.0-rc6
Hardware: Skylake based reference board

> ---
> In v2:
> - address Rajneesh's comments
>  drivers/platform/x86/intel_pmc_core.c | 45 ++++++++---------------------------
>  drivers/platform/x86/intel_pmc_core.h |  3 +--
>  2 files changed, 11 insertions(+), 37 deletions(-)
> 
> diff --git a/drivers/platform/x86/intel_pmc_core.c b/drivers/platform/x86/intel_pmc_core.c
> index 2776bec..d8379cd 100644
> --- a/drivers/platform/x86/intel_pmc_core.c
> +++ b/drivers/platform/x86/intel_pmc_core.c
> @@ -23,7 +23,6 @@
>  #include <linux/init.h>
>  #include <linux/io.h>
>  #include <linux/pci.h>
> -#include <linux/seq_file.h>
>  
>  #include <asm/cpu_device_id.h>
>  #include <asm/pmc_core.h>
> @@ -77,30 +76,18 @@ int intel_pmc_slp_s0_counter_read(u32 *data)
>  }
>  EXPORT_SYMBOL_GPL(intel_pmc_slp_s0_counter_read);
>  
> -#if IS_ENABLED(CONFIG_DEBUG_FS)
> -static int pmc_core_dev_state_show(struct seq_file *s, void *unused)
> +static int pmc_core_dev_state_get(void *data, u64 *val)
>  {
> -	struct pmc_dev *pmcdev = s->private;
> -	u32 counter_val;
> +	struct pmc_dev *pmcdev = data;
> +	u32 value;
>  
> -	counter_val = pmc_core_reg_read(pmcdev,
> -					SPT_PMC_SLP_S0_RES_COUNTER_OFFSET);
> -	seq_printf(s, "%u\n", pmc_core_adjust_slp_s0_step(counter_val));
> +	value = pmc_core_reg_read(pmcdev, SPT_PMC_SLP_S0_RES_COUNTER_OFFSET);
> +	*val = pmc_core_adjust_slp_s0_step(value);
>  
>  	return 0;
>  }
>  
> -static int pmc_core_dev_state_open(struct inode *inode, struct file *file)
> -{
> -	return single_open(file, pmc_core_dev_state_show, inode->i_private);
> -}
> -
> -static const struct file_operations pmc_core_dev_state_ops = {
> -	.open           = pmc_core_dev_state_open,
> -	.read           = seq_read,
> -	.llseek         = seq_lseek,
> -	.release        = single_release,
> -};
> +DEFINE_DEBUGFS_ATTRIBUTE(pmc_core_dev_state, pmc_core_dev_state_get, NULL, "%llu\n");
>  
>  static void pmc_core_dbgfs_unregister(struct pmc_dev *pmcdev)
>  {
> @@ -112,12 +99,12 @@ static int pmc_core_dbgfs_register(struct pmc_dev *pmcdev)
>  	struct dentry *dir, *file;
>  
>  	dir = debugfs_create_dir("pmc_core", NULL);
> -	if (!dir)
> +	if (IS_ERR_OR_NULL(dir))
>  		return -ENOMEM;
>  
>  	pmcdev->dbgfs_dir = dir;
>  	file = debugfs_create_file("slp_s0_residency_usec", S_IFREG | S_IRUGO,
> -				   dir, pmcdev, &pmc_core_dev_state_ops);
> +				   dir, pmcdev, &pmc_core_dev_state);
>  
>  	if (!file) {
>  		pmc_core_dbgfs_unregister(pmcdev);
> @@ -126,16 +113,6 @@ static int pmc_core_dbgfs_register(struct pmc_dev *pmcdev)
>  
>  	return 0;
>  }
> -#else
> -static inline int pmc_core_dbgfs_register(struct pmc_dev *pmcdev)
> -{
> -	return 0;
> -}
> -
> -static inline void pmc_core_dbgfs_unregister(struct pmc_dev *pmcdev)
> -{
> -}
> -#endif /* CONFIG_DEBUG_FS */
>  
>  static const struct x86_cpu_id intel_pmc_core_ids[] = {
>  	{ X86_VENDOR_INTEL, 6, 0x4e, X86_FEATURE_MWAIT,
> @@ -182,10 +159,8 @@ static int pmc_core_probe(struct pci_dev *dev, const struct pci_device_id *id)
>  	}
>  
>  	err = pmc_core_dbgfs_register(pmcdev);
> -	if (err < 0) {
> -		dev_err(&dev->dev, "PMC Core: debugfs register failed.\n");
> -		return err;
> -	}
> +	if (err < 0)
> +		dev_warn(&dev->dev, "PMC Core: debugfs register failed.\n");
>  
>  	pmc.has_slp_s0_res = true;
>  	return 0;
> diff --git a/drivers/platform/x86/intel_pmc_core.h b/drivers/platform/x86/intel_pmc_core.h
> index a9dadaf..e3f671f 100644
> --- a/drivers/platform/x86/intel_pmc_core.h
> +++ b/drivers/platform/x86/intel_pmc_core.h
> @@ -23,6 +23,7 @@
>  
>  /* Sunrise Point Power Management Controller PCI Device ID */
>  #define SPT_PMC_PCI_DEVICE_ID			0x9d21
> +
>  #define SPT_PMC_BASE_ADDR_OFFSET		0x48
>  #define SPT_PMC_SLP_S0_RES_COUNTER_OFFSET	0x13c
>  #define SPT_PMC_MMIO_REG_LEN			0x100
> @@ -42,9 +43,7 @@
>  struct pmc_dev {
>  	u32 base_addr;
>  	void __iomem *regbase;
> -#if IS_ENABLED(CONFIG_DEBUG_FS)
>  	struct dentry *dbgfs_dir;
> -#endif /* CONFIG_DEBUG_FS */
>  	bool has_slp_s0_res;
>  };
>  
> -- 
> 2.8.1
> 

-- 
Best Regards,
Rajneesh