• Stanley Chu's avatar
    scsi: ufs: Remove "<name>-fixed-regulator" device tree property · 94e424c6
    Stanley Chu authored
    "<name>-fixed-regulator" device tree property can be safely removed because
    below things are fixed or resolved,
    
    1. "<name>-max-microamp" becomes optional property: Undefined
       "<name>-max-microamp" will not cause initialization fail if
       "<name>-fixed-regulator" is not defined.
    
    2. Current switching operation (by regulator_set_load) now has rules:
       Regulators will have undefined current limit if "<name>-fixed-regulator"
       is not defined. But this is safe because only regulator which has
       configured current limit from "<name>-max-microamp" property is allowed
       to change its load.
    
    Although "<name>-fixed-regulator" is not used in any dt-bindings in tree,
    this patch is still safe for regulators already defined
    "<name>-fixed-regulator". To be more clear, if a regulator defined
    "<name>-fixed-regulator" before, the behavior difference after this patch
    is,
    
    1. "<name>-max-microamp":
       If a regulator defined "<name>-fixed-regulator", it is not necessary
       to define "<name>-max-microamp" property in device tree and it is
       expected to have an undefined current limit, i.e., "max_uA" field
       is zero in struct ufs_vreg. This is exactly the same as patched.
    
    2. "vcc-supply-1p8" or volatge range settings:
       * For vcc, vccq or vccq2, these three regulators shall not define
         "<name>-fixed-regulator" because defining it will lead to
         undefined voltage range and thus voltage switching will be
         unexpected.
       * For other regulators with undefined voltage range, voltage range
         will be still undefined after patched.
    
    Therefore this patch is safe for all existed regulators with
    "<name>-fixed-regulator" property already defined.
    Signed-off-by: default avatarStanley Chu <stanley.chu@mediatek.com>
    Reviewed-by: default avatarAvri Altman <avri.altman@wdc.com>
    Acked-by: default avatarAlim Akhtar <alim.akhtar@samsung.com>
    Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
    94e424c6
ufshcd-pltfrm.c 12.2 KB