On Mon, 18 May 2020 14:19:11 +0000
Jean-Baptiste Maneyrol <JManeyrol@xxxxxxxxxxxxxx> wrote:
> Hi Jonathan,
>
> I am using generic device_get_match_data because I was thinking it was now the way to go. But since only of is supported with the driver, I can switch to using of_device_get_match_data instead.
>
> Tell me what do you think is better.
Leave it as you have it. We can look at if we can tidy up
what I was rambling about as a separate exercise.
J
>
> I could definitely use the new probe interface indeed, good idea.
>
> Thanks,
> JB
>
>
>
> From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
>
> Sent: Friday, May 8, 2020 15:44
>
> To: Jean-Baptiste Maneyrol <JManeyrol@xxxxxxxxxxxxxx>
>
> Cc: jic23@xxxxxxxxxx <jic23@xxxxxxxxxx>; robh+dt@xxxxxxxxxx <robh+dt@xxxxxxxxxx>; robh@xxxxxxxxxx <robh@xxxxxxxxxx>; mchehab+huawei@xxxxxxxxxx <mchehab+huawei@xxxxxxxxxx>; davem@xxxxxxxxxxxxx <davem@xxxxxxxxxxxxx>; gregkh@xxxxxxxxxxxxxxxxxxx <gregkh@xxxxxxxxxxxxxxxxxxx>;
> linux-iio@xxxxxxxxxxxxxxx <linux-iio@xxxxxxxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx <devicetree@xxxxxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx <linux-kernel@xxxxxxxxxxxxxxx>
>
> Subject: Re: [PATCH 02/12] iio: imu: inv_icm42600: add I2C driver for inv_icm42600 driver
>
>
>
>
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>
>
> On Thu, 7 May 2020 16:42:12 +0200
>
> Jean-Baptiste Maneyrol <jmaneyrol@xxxxxxxxxxxxxx> wrote:
>
>
>
> > Add I2C driver for InvenSense ICM-426xxx devices.
>
> >
>
> > Configure bus signal slew rates as indicated in the datasheet.
>
> >
>
> > Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@xxxxxxxxxxxxxx>
>
> Some incoherent rambling inline. + a few comments
>
>
>
> Jonathan
>
>
>
> > ---
>
> > .../iio/imu/inv_icm42600/inv_icm42600_i2c.c | 117 ++++++++++++++++++
>
> > 1 file changed, 117 insertions(+)
>
> > create mode 100644 drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c
>
> >
>
> > diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c b/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c
>
> > new file mode 100644
>
> > index 000000000000..b61f993beacf
>
> > --- /dev/null
>
> > +++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c
>
> > @@ -0,0 +1,117 @@
>
> > +// SPDX-License-Identifier: GPL-2.0-or-later
>
> > +/*
>
> > + * Copyright (C) 2020 InvenSense, Inc.
>
> > + */
>
> > +
>
> > +#include <linux/device.h>
>
> > +#include <linux/module.h>
>
> > +#include <linux/i2c.h>
>
> > +#include <linux/regmap.h>
>
> > +#include <linux/of_device.h>
>
>
>
> Why? Looks like you need the table and the device property stuff neither
>
> of which are in that file.
>
>
>
> linux/mod_devicetable.h
>
> linux/property.h
>
>
>
>
>
> > +
>
> > +#include "inv_icm42600.h"
>
> > +
>
> > +static int inv_icm42600_i2c_bus_setup(struct inv_icm42600_state *st)
>
> > +{
>
> > + unsigned int mask, val;
>
> > + int ret;
>
> > +
>
> > + /* setup interface registers */
>
> > + mask = INV_ICM42600_INTF_CONFIG6_MASK;
>
> > + val = INV_ICM42600_INTF_CONFIG6_I3C_EN;
>
> > + ret = regmap_update_bits(st->map, INV_ICM42600_REG_INTF_CONFIG6,
>
> > + mask, val);
>
>
>
> I'd put the values inline where they are simple like these rather than
>
> using local variables.
>
>
>
> > + if (ret)
>
> > + return ret;
>
> > +
>
> > + mask = INV_ICM42600_INTF_CONFIG4_I3C_BUS_ONLY;
>
> > + val = 0;
>
> > + ret = regmap_update_bits(st->map, INV_ICM42600_REG_INTF_CONFIG4,
>
> > + mask, val);
>
> > + if (ret)
>
> > + return ret;
>
> > +
>
> > + /* set slew rates for I2C and SPI */
>
> > + mask = INV_ICM42600_DRIVE_CONFIG_I2C_MASK |
>
> > + INV_ICM42600_DRIVE_CONFIG_SPI_MASK;
>
> > + val = INV_ICM42600_DRIVE_CONFIG_I2C(INV_ICM42600_SLEW_RATE_12_36NS) |
>
> > + INV_ICM42600_DRIVE_CONFIG_SPI(INV_ICM42600_SLEW_RATE_12_36NS);
>
> > + ret = regmap_update_bits(st->map, INV_ICM42600_REG_DRIVE_CONFIG,
>
> > + mask, val);
>
> > + if (ret)
>
> > + return ret;
>
> > +
>
> > + /* disable SPI bus */
>
> > + mask = INV_ICM42600_INTF_CONFIG0_UI_SIFS_CFG_MASK;
>
> > + val = INV_ICM42600_INTF_CONFIG0_UI_SIFS_CFG_SPI_DIS;
>
> > + return regmap_update_bits(st->map, INV_ICM42600_REG_INTF_CONFIG0,
>
> > + mask, val);
>
> > +}
>
> > +
>
> > +static int inv_icm42600_probe(struct i2c_client *client,
>
> > + const struct i2c_device_id *id)
>
> > +{
>
> > + const void *match;
>
> > + enum inv_icm42600_chip chip;
>
> > + struct regmap *regmap;
>
> > +
>
> > + if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
>
> > + return -ENOTSUPP;
>
> > +
>
> > + match = device_get_match_data(&client->dev);
>
>
>
> Hmm. Annoyingly if one were to call the of specific option
>
> of i2c_of_match_device it would handle the old style i2c match just fine without
>
> needing special handling. However, it would fail to handle PRP0001 ACPI.
>
>
>
> Rather feels like there should be something similar for
>
> device_get_match_data so we could use the probe_new version of i2c device
>
> probing.
>
>
>
> Oh well. I guess thats a separate question for another day ;)
>
>
>
> Mind you can we actually probe this driver via the sysfs route?
>
> If not why do we need to handle the non firmware case at all?
>
>
>
> > + if (match)
>
> > + chip = (enum inv_icm42600_chip)match;
>
> > + else if (id)
>
> > + chip = (enum inv_icm42600_chip)id->driver_data;
>
> > + else
>
> > + return -EINVAL;
>
> > +
>
> > + regmap = devm_regmap_init_i2c(client, &inv_icm42600_regmap_config);
>
> > + if (IS_ERR(regmap))
>
> > + return PTR_ERR(regmap);
>
> > +
>
> > + return inv_icm42600_core_probe(regmap, chip,
>
> > + inv_icm42600_i2c_bus_setup);
>
> > +}
>
> > +
>
> > +static const struct of_device_id inv_icm42600_of_matches[] = {
>
> > + {
>
> > + .compatible = "invensense,icm42600",
>
> > + .data = (void *)INV_CHIP_ICM42600,
>
> > + }, {
>
> > + .compatible = "invensense,icm42602",
>
> > + .data = (void *)INV_CHIP_ICM42602,
>
> > + }, {
>
> > + .compatible = "invensense,icm42605",
>
> > + .data = (void *)INV_CHIP_ICM42605,
>
> > + }, {
>
> > + .compatible = "invensense,icm42622",
>
> > + .data = (void *)INV_CHIP_ICM42622,
>
> > + },
>
> > + {}
>
> > +};
>
> > +MODULE_DEVICE_TABLE(of, inv_icm42600_of_matches);
>
> > +
>
> > +static const struct i2c_device_id inv_icm42600_ids[] = {
>
> > + {"icm42600", INV_CHIP_ICM42600},
>
> > + {"icm42602", INV_CHIP_ICM42602},
>
> > + {"icm42605", INV_CHIP_ICM42605},
>
> > + {"icm42622", INV_CHIP_ICM42622},
>
> > + {}
>
> > +};
>
> > +MODULE_DEVICE_TABLE(i2c, inv_icm42600_ids);
>
> > +
>
> > +static struct i2c_driver inv_icm42600_driver = {
>
> > + .probe = inv_icm42600_probe,
>
> > + .id_table = inv_icm42600_ids,
>
> > + .driver = {
>
> > + .of_match_table = inv_icm42600_of_matches,
>
> > + .name = "inv-icm42600-i2c",
>
> > + .pm = &inv_icm42600_pm_ops,
>
> > + },
>
> > +};
>
> > +module_i2c_driver(inv_icm42600_driver);
>
> > +
>
> > +MODULE_AUTHOR("InvenSense, Inc.");
>
> > +MODULE_DESCRIPTION("InvenSense ICM-426xx I2C driver");
>
> > +MODULE_LICENSE("GPL");
>
>
>
>
>
