Re: [PATCH v2 07/10] scsi: esas2r: Use FIELD_GET() to extract PCIe capability fields

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Wed, 13 Sep 2023 15:27:45 +0300
Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> wrote:

> Use FIELD_GET() to extract PCIe capability register fields instead of
> custom masking and shifting. Also remove the unnecessary cast to u8,
> the value in those fields always fits to u8.
> 
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/scsi/esas2r/esas2r_ioctl.c | 16 ++++++----------
>  1 file changed, 6 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/scsi/esas2r/esas2r_ioctl.c b/drivers/scsi/esas2r/esas2r_ioctl.c
> index 055d2e87a2c8..3f7c1d131ec3 100644
> --- a/drivers/scsi/esas2r/esas2r_ioctl.c
> +++ b/drivers/scsi/esas2r/esas2r_ioctl.c
> @@ -41,6 +41,8 @@
>   * USA.
>   */
>  
> +#include <linux/bitfield.h>
> +
>  #include "esas2r.h"
>  
>  /*
> @@ -792,16 +794,10 @@ static int hba_ioctl_callback(struct esas2r_adapter *a,
>  			pcie_capability_read_dword(a->pcid, PCI_EXP_LNKCAP,
>  						   &caps);
>  
> -			gai->pci.link_speed_curr =
> -				(u8)(stat & PCI_EXP_LNKSTA_CLS);
> -			gai->pci.link_speed_max =
> -				(u8)(caps & PCI_EXP_LNKCAP_SLS);
> -			gai->pci.link_width_curr =
> -				(u8)((stat & PCI_EXP_LNKSTA_NLW)
> -				     >> PCI_EXP_LNKSTA_NLW_SHIFT);  
> -			gai->pci.link_width_max =
> -				(u8)((caps & PCI_EXP_LNKCAP_MLW)
> -				     >> 4);  
> +			gai->pci.link_speed_curr = FIELD_GET(PCI_EXP_LNKSTA_CLS, stat);
> +			gai->pci.link_speed_max = FIELD_GET(PCI_EXP_LNKCAP_SLS, caps);
> +			gai->pci.link_width_curr = FIELD_GET(PCI_EXP_LNKSTA_NLW, stat);
> +			gai->pci.link_width_max = FIELD_GET(PCI_EXP_LNKCAP_MLW, caps);
>  		}
>  
>  		gai->pci.msi_vector_cnt = 1;