[PATCH v4 3/6] lib: utils/i2c: Add generic I2C configuration library
Nikita Shubin
nikita.shubin at maquefel.me
Wed Nov 10 09:05:46 PST 2021
On Wed, 10 Nov 2021 22:31:08 +0530
Anup Patel <anup at brainfault.org> wrote:
> On Wed, Nov 10, 2021 at 9:58 PM Nikita Shubin
> <nikita.shubin at maquefel.me> wrote:
> >
> > On Wed, 10 Nov 2021 21:01:39 +0800
> > Xiang W <wxjstz at 126.com> wrote:
> >
> > > 在 2021-11-10星期三的 12:42 +0300，Nikita Shubin写道：
> > > > From: Nikita Shubin <n.shubin at yadro.com>
> > > >
> > > > Helper library to keep track of registered I2C adapters,
> > > > identified by dts offset, basic send/read functions and
> > > > adapter configuration (enable, set dividers, etc...).
> > > >
> > > > Tested-by: Heinrich Schuchardt
> > > > <heinrich.schuchardt at canonical.com> Reviewed-by: Alexandre
> > > > Ghiti <alexandre.ghiti at canonical.com> Tested-by: Alexandre
> > > > Ghiti <alexandre.ghiti at canonical.com> Signed-off-by: Nikita
> > > > Shubin <n.shubin at yadro.com>
> > > The i2c bus does not define register-related operations, these
> > > interfaces should be renamed smbus
> >
> > You are right, it was in first series of patches and i dropped it as
> > there is no non-smbus version currently.
> >
> > So let's resend. I hope this change is trivial enough so i can keep
> > the tags.
>
> I think what we have is good to go.
Okay, no problem - we can always rename later if raw i2c read/write will
come up.
>
> Regards,
> Anup
>
> >
> > >
> > > Regards,
> > > Xiang W
> > > > ---
> > > > v3->v4:
> > > > - fixed typo in include/sbi_utils/i2c/i2c.h
> > > > - fixed inaccurate configure remove, leaked into patch 0004
> > > > ---
> > > > include/sbi_utils/i2c/i2c.h | 85
> > > > +++++++++++++++++++++++++++++++++++++
> > > > lib/utils/i2c/i2c.c | 75
> > > > ++++++++++++++++++++++++++++++++ lib/utils/i2c/objects.mk |
> > > > 10 +++++ 3 files changed, 170 insertions(+)
> > > > create mode 100644 include/sbi_utils/i2c/i2c.h
> > > > create mode 100644 lib/utils/i2c/i2c.c
> > > > create mode 100644 lib/utils/i2c/objects.mk
> > > >
> > > > diff --git a/include/sbi_utils/i2c/i2c.h
> > > > b/include/sbi_utils/i2c/i2c.h
> > > > new file mode 100644
> > > > index 0000000..79aeeb5
> > > > --- /dev/null
> > > > +++ b/include/sbi_utils/i2c/i2c.h
> > > > @@ -0,0 +1,85 @@
> > > > +/*
> > > > + * SPDX-License-Identifier: BSD-2-Clause
> > > > + *
> > > > + * Copyright (c) 2021 YADRO
> > > > + *
> > > > + * Authors:
> > > > + * Nikita Shubin <n.shubin at yadro.com>
> > > > + */
> > > > +
> > > > +#ifndef __I2C_H__
> > > > +#define __I2C_H__
> > > > +
> > > > +#include <sbi/sbi_types.h>
> > > > +#include <sbi/sbi_list.h>
> > > > +
> > > > +/** Representation of a I2C adapter */
> > > > +struct i2c_adapter {
> > > > + /** Pointer to I2C driver owning this I2C adapter */
> > > > + void *driver;
> > > > +
> > > > + /** Unique ID of the I2C adapter assigned by the driver
> > > > */
> > > > + int id;
> > > > +
> > > > + /**
> > > > + * Send buffer to given address, register
> > > > + *
> > > > + * @return 0 on success and negative error code on
> > > > failure
> > > > + */
> > > > + int (*write)(struct i2c_adapter *ia, uint8_t addr,
> > > > uint8_t reg,
> > > > + uint8_t *buffer, int len);
> > > > +
> > > > + /**
> > > > + * Read buffer from given address, register
> > > > + *
> > > > + * @return 0 on success and negative error code on
> > > > failure
> > > > + */
> > > > + int (*read)(struct i2c_adapter *ia, uint8_t addr,
> > > > uint8_t reg,
> > > > + uint8_t *buffer, int len);
> > > > +
> > > > + /** List */
> > > > + struct sbi_dlist node;
> > > > +};
> > > > +
> > > > +static inline struct i2c_adapter *to_i2c_adapter(struct
> > > > sbi_dlist *node)
> > > > +{
> > > > + return container_of(node, struct i2c_adapter, node);
> > > > +}
> > > > +
> > > > +/** Find a registered I2C adapter */
> > > > +struct i2c_adapter *i2c_adapter_find(int id);
> > > > +
> > > > +/** Register I2C adapter */
> > > > +int i2c_adapter_add(struct i2c_adapter *ia);
> > > > +
> > > > +/** Un-register I2C adapter */
> > > > +void i2c_adapter_remove(struct i2c_adapter *ia);
> > > > +
> > > > +/** Send to device on I2C adapter bus */
> > > > +int i2c_adapter_write(struct i2c_adapter *ia, uint8_t addr,
> > > > uint8_t reg,
> > > > + uint8_t *buffer, int len);
> > > > +
> > > > +/** Read from device on I2C adapter bus */
> > > > +int i2c_adapter_read(struct i2c_adapter *ia, uint8_t addr,
> > > > uint8_t reg,
> > > > + uint8_t *buffer, int len);
> > > > +
> > > > +static inline int i2c_adapter_reg_write(struct i2c_adapter *ia,
> > > > uint8_t addr,
> > > > + uint8_t reg, uint8_t val)
> > > > +{
> > > > + return i2c_adapter_write(ia, addr, reg, &val, 1);
> > > > +}
> > > > +
> > > > +static inline int i2c_adapter_reg_read(struct i2c_adapter *ia,
> > > > uint8_t addr,
> > > > + uint8_t reg, uint8_t
> > > > *val) +{
> > > > + uint8_t buf;
> > > > + int ret = i2c_adapter_read(ia, addr, reg, &buf, 1);
> > > > +
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + *val = buf;
> > > > + return 0;
> > > > +}
> > > > +
> > > > +#endif
> > > > diff --git a/lib/utils/i2c/i2c.c b/lib/utils/i2c/i2c.c
> > > > new file mode 100644
> > > > index 0000000..1f5072c
> > > > --- /dev/null
> > > > +++ b/lib/utils/i2c/i2c.c
> > > > @@ -0,0 +1,75 @@
> > > > +/*
> > > > + * SPDX-License-Identifier: BSD-2-Clause
> > > > + *
> > > > + * Copyright (c) 2021 YADRO
> > > > + *
> > > > + * Authors:
> > > > + * Nikita Shubin <n.shubin at yadro.com>
> > > > + *
> > > > + * derivate: lib/utils/gpio/gpio.c
> > > > + * Authors:
> > > > + * Anup Patel <anup.patel at wdc.com>
> > > > + */
> > > > +
> > > > +#include <sbi/sbi_error.h>
> > > > +#include <sbi_utils/i2c/i2c.h>
> > > > +
> > > > +static SBI_LIST_HEAD(i2c_adapters_list);
> > > > +
> > > > +struct i2c_adapter *i2c_adapter_find(int id)
> > > > +{
> > > > + struct sbi_dlist *pos;
> > > > +
> > > > + sbi_list_for_each(pos, &(i2c_adapters_list)) {
> > > > + struct i2c_adapter *adap = to_i2c_adapter(pos);
> > > > +
> > > > + if (adap->id == id)
> > > > + return adap;
> > > > + }
> > > > +
> > > > + return NULL;
> > > > +}
> > > > +
> > > > +int i2c_adapter_add(struct i2c_adapter *ia)
> > > > +{
> > > > + if (!ia)
> > > > + return SBI_EINVAL;
> > > > +
> > > > + if (i2c_adapter_find(ia->id))
> > > > + return SBI_EALREADY;
> > > > +
> > > > + sbi_list_add(&(ia->node), &(i2c_adapters_list));
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +void i2c_adapter_remove(struct i2c_adapter *ia)
> > > > +{
> > > > + if (!ia)
> > > > + return;
> > > > +
> > > > + sbi_list_del(&(ia->node));
> > > > +}
> > > > +
> > > > +int i2c_adapter_write(struct i2c_adapter *ia, uint8_t addr,
> > > > uint8_t reg,
> > > > + uint8_t *buffer, int len)
> > > > +{
> > > > + if (!ia)
> > > > + return SBI_EINVAL;
> > > > + if (!ia->write)
> > > > + return SBI_ENOSYS;
> > > > +
> > > > + return ia->write(ia, addr, reg, buffer, len);
> > > > +}
> > > > +
> > > > +
> > > > +int i2c_adapter_read(struct i2c_adapter *ia, uint8_t addr,
> > > > uint8_t reg,
> > > > + uint8_t *buffer, int len)
> > > > +{
> > > > + if (!ia)
> > > > + return SBI_EINVAL;
> > > > + if (!ia->read)
> > > > + return SBI_ENOSYS;
> > > > +
> > > > + return ia->read(ia, addr, reg, buffer, len);
> > > > +}
> > > > diff --git a/lib/utils/i2c/objects.mk b/lib/utils/i2c/objects.mk
> > > > new file mode 100644
> > > > index 0000000..16a70da
> > > > --- /dev/null
> > > > +++ b/lib/utils/i2c/objects.mk
> > > > @@ -0,0 +1,10 @@
> > > > +#
> > > > +# SPDX-License-Identifier: BSD-2-Clause
> > > > +#
> > > > +# Copyright (c) 2021 YADRO
> > > > +#
> > > > +# Authors:
> > > > +# Nikita Shubin <n.shubin at yadro.com>
> > > > +#
> > > > +
> > > > +libsbiutils-objs-y += i2c/i2c.o
> > > > --
> > > > 2.31.1
> > > >
> > > >
> > >
> > >
> >
> >
> > --
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