[PATCH v2 1/4] regmap: provide regmap_field helpers for simple bit operations

Li Chen lchen.firstlove at zohomail.com
Sun May 22 20:30:59 PDT 2022


Hi Samuel,

 ---- On Sun, 22 May 2022 20:09:55 -0700 Samuel Holland <samuel at sholland.org> wrote ----
 > Hi,
 > 
 > On 5/22/22 9:23 PM, Li Chen wrote:
 > > From: Li Chen <lchen at ambarella.com>
 > > 
 > > We have set/clear/test operations for regmap, but not for regmap_field yet.
 > > So let's introduce regmap_field helpers too.
 > > 
 > > In many instances regmap_field_update_bits() is used for simple bit setting
 > > and clearing. In these cases the last argument is redundant and we can
 > > hide it with a static inline function.
 > > 
 > > This adds three new helpers for simple bit operations: set_bits,
 > > clear_bits and test_bits (the last one defined as a regular function).
 > > 
 > > Signed-off-by: Li Chen <lchen at ambarella.com>
 > > ---
 > >  drivers/base/regmap/regmap.c | 22 +++++++++++++++++++++
 > >  include/linux/regmap.h       | 37 ++++++++++++++++++++++++++++++++++++
 > >  2 files changed, 59 insertions(+)
 > > 
 > > diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
 > > index 5e12f7cb5147..a37d6041b7bd 100644
 > > --- a/drivers/base/regmap/regmap.c
 > > +++ b/drivers/base/regmap/regmap.c
 > > @@ -2208,6 +2208,28 @@ int regmap_field_update_bits_base(struct regmap_field *field,
 > >  }
 > >  EXPORT_SYMBOL_GPL(regmap_field_update_bits_base);
 > >  
 > > +/**
 > > + * regmap_field_test_bits() - Check if all specified bits are set in a
 > > + *                            register field.
 > > + *
 > > + * @field: Register field to operate on
 > > + * @bits: Bits to test
 > > + *
 > > + * Returns -1 if the underlying regmap_field_read() fails, 0 if at least one of the
 > > + * tested bits is not set and 1 if all tested bits are set.
 > > + */
 > > +int regmap_field_test_bits(struct regmap_field *field, unsigned int bits)
 > > +{
 > > +    unsigned int val, ret;
 > > +
 > > +    ret = regmap_field_read(field, &val);
 > > +    if (ret)
 > > +        return ret;
 > > +
 > > +    return (val & bits) == bits;
 > > +}
 > > +EXPORT_SYMBOL_GPL(regmap_field_test_bits);
 > > +
 > >  /**
 > >   * regmap_fields_update_bits_base() - Perform a read/modify/write cycle a
 > >   *                                    register field with port ID
 > > diff --git a/include/linux/regmap.h b/include/linux/regmap.h
 > > index de81a94d7b30..10b410734d9e 100644
 > > --- a/include/linux/regmap.h
 > > +++ b/include/linux/regmap.h
 > > @@ -1324,6 +1324,22 @@ static inline int regmap_field_update_bits(struct regmap_field *field,
 > >                           NULL, false, false);
 > >  }
 > >  
 > > +static inline int regmap_field_set_bits(struct regmap_field *field,
 > > +                    unsigned int bits)
 > > +{
 > > +    return regmap_field_update_bits_base(field, bits, 0, NULL, false,
 > > +                         false);
 > > +}
 > > +
 > > +static inline int regmap_field_clear_bits(struct regmap_field *field,
 > > +                      unsigned int bits)
 > > +{
 > > +    return regmap_field_update_bits_base(field, bits, bits, NULL, false,
 > > +                         false);
 > 
 > The contents of these two functions are swapped when compared to their names.

Thanks for spotting this out!
Fixed in v3.

Regards,
Li
 > 
 > Regards,
 > Samuel
 > 
 > > +}
 > > +
 > > +int regmap_field_test_bits(struct regmap_field *field, unsigned int bits);
 > > +
 > >  static inline int
 > >  regmap_field_force_update_bits(struct regmap_field *field,
 > >                     unsigned int mask, unsigned int val)
 > > @@ -1757,6 +1773,27 @@ regmap_field_force_update_bits(struct regmap_field *field,
 > >      return -EINVAL;
 > >  }
 > >  
 > > +static inline int regmap_field_set_bits(struct regmap_field *field,
 > > +                    unsigned int bits)
 > > +{
 > > +    WARN_ONCE(1, "regmap API is disabled");
 > > +    return -EINVAL;
 > > +}
 > > +
 > > +static inline int regmap_field_clear_bits(struct regmap_field *field,
 > > +                      unsigned int bits)
 > > +{
 > > +    WARN_ONCE(1, "regmap API is disabled");
 > > +    return -EINVAL;
 > > +}
 > > +
 > > +static inline int regmap_field_test_bits(struct regmap_field *field,
 > > +                     unsigned int bits)
 > > +{
 > > +    WARN_ONCE(1, "regmap API is disabled");
 > > +    return -EINVAL;
 > > +}
 > > +
 > >  static inline int regmap_fields_write(struct regmap_field *field,
 > >                        unsigned int id, unsigned int val)
 > >  {
 > > 
 > 
 > 



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