Re: [PATCH 06/11] mux: Add Pericom PI3USB30532 Type-C mux driver

Peter Rosin
2017-09-05T07:47:17Z

On 2017-09-04 13:19, Peter Rosin wrote:
> Hi!
>
> One comment inline...

Oh, and one more small nit, I think you should do

s/pi3usb30532_mux/pi3usb30532/g

to shorten the identifiers a bit. The _mux suffix (or infix) is kind of
selfevident from where the file lives anyway. pi3usb30532_mux_set_mux in
particular feels a bit much....

Cheers,
peda

> On 2017-09-01 23:48, Hans de Goede wrote:
>> Add a driver for the Pericom PI3USB30532 Type-C cross switch /
>> mux chip found on some devices with a Type-C port.
>>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>> drivers/mux/Kconfig | 10 +++++
>> drivers/mux/Makefile | 2 +
>> drivers/mux/pi3usb30532.c | 97 +++++++++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 109 insertions(+)
>> create mode 100644 drivers/mux/pi3usb30532.c
>>
>> diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
>> index 17938918bf93..19a3065c34e6 100644
>> --- a/drivers/mux/Kconfig
>> +++ b/drivers/mux/Kconfig
>> @@ -58,4 +58,14 @@ config MUX_MMIO
>> To compile the driver as a module, choose M here: the module will
>> be called mux-mmio.
>>
>> +config MUX_PI3USB30532
>> + tristate "Pericom PI3USB30532 Type-C cross switch driver"
>> + depends on I2C
>> + help
>> + This driver adds support for the Pericom PI3USB30532 Type-C cross
>> + switch / mux chip found on some devices with a Type-C port.
>> +
>> + To compile the driver as a module, choose M here: the module will
>> + be called mux-pi3usb30532.
>> +
>> endmenu
>> diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile
>> index a12e812c7966..7563dbf04593 100644
>> --- a/drivers/mux/Makefile
>> +++ b/drivers/mux/Makefile
>> @@ -7,9 +7,11 @@ mux-adg792a-objs := adg792a.o
>> mux-gpio-objs := gpio.o
>> mux-mmio-objs := mmio.o
>> mux-intel_cht_usb_mux-objs := intel_cht_usb_mux.o
>> +mux-pi3usb30532-objs := pi3usb30532.o
>>
>> obj-$(CONFIG_MULTIPLEXER) += mux-core.o
>> obj-$(CONFIG_MUX_ADG792A) += mux-adg792a.o
>> obj-$(CONFIG_MUX_GPIO) += mux-gpio.o
>> obj-$(CONFIG_MUX_MMIO) += mux-mmio.o
>> obj-$(CONFIG_MUX_CHT_USB_MUX) += mux-intel_cht_usb_mux.o
>> +obj-$(CONFIG_MUX_PI3USB30532) += mux-pi3usb30532.o
>> diff --git a/drivers/mux/pi3usb30532.c b/drivers/mux/pi3usb30532.c
>> new file mode 100644
>> index 000000000000..fa8abd851520
>> --- /dev/null
>> +++ b/drivers/mux/pi3usb30532.c
>> @@ -0,0 +1,97 @@
>> +/*
>> + * Pericom PI3USB30532 Type-C cross switch / mux driver
>> + *
>> + * Copyright (c) 2017 Hans de Goede <hdegoede@redhat.com>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation, or (at your option)
>> + * any later version.
>> + */
>> +
>> +#include <linux/i2c.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/mux/consumer.h> /* For the MUX_USB_* defines */
>> +#include <linux/mux/driver.h>
>> +
>> +#define PI3USB30532_CONF 0x00
>> +
>> +#define PI3USB30532_CONF_OPEN 0x00
>> +#define PI3USB30532_CONF_SWAP 0x01
>> +#define PI3USB30532_CONF_4LANE_DP 0x02
>> +#define PI3USB30532_CONF_USB3 0x04
>> +#define PI3USB30532_CONF_USB3_AND_2LANE_DP 0x06
>> +
>> +struct pi3usb30532_mux {
>> + struct i2c_client *client;
>> +};
>> +
>> +static int pi3usb30532_mux_set_mux(struct mux_control *mux_ctrl, int state)
>> +{
>> + struct pi3usb30532_mux *mux = mux_chip_priv(mux_ctrl->chip);
>
> The "mux" variable name is used for the mux_control in other drivers, and
> I don't think the private data is needed. Like so:
>
> static int pi3usb30532_mux_set_mux(struct mux_control *mux, int state)
> {
> struct i2c_client *i2c = to_i2c_client(mux->chip->dev.parent);
>
> ...
>
> Cheers,
> Peter
>
>> + u8 conf = PI3USB30532_CONF_OPEN;
>> +
>> + switch (state & ~MUX_USB_POLARITY_INV) {
>> + case MUX_USB_NONE:
>> + conf = PI3USB30532_CONF_OPEN;
>> + break;
>> + case MUX_USB_DEVICE:
>> + case MUX_USB_HOST:
>> + conf = PI3USB30532_CONF_USB3;
>> + break;
>> + case MUX_USB_HOST_AND_DP_SRC:
>> + conf = PI3USB30532_CONF_USB3_AND_2LANE_DP;
>> + break;
>> + case MUX_USB_DP_SRC:
>> + conf = PI3USB30532_CONF_4LANE_DP;
>> + break;
>> + }
>> +
>> + if (state & MUX_USB_POLARITY_INV)
>> + conf |= PI3USB30532_CONF_SWAP;
>> +
>> + return i2c_smbus_write_byte_data(mux->client, PI3USB30532_CONF, conf);
>> +}
>> +
>> +static const struct mux_control_ops pi3usb30532_mux_ops = {
>> + .set = pi3usb30532_mux_set_mux,
>> +};
>> +
>> +static int pi3usb30532_mux_probe(struct i2c_client *client)
>> +{
>> + struct device *dev = &client->dev;
>> + struct pi3usb30532_mux *mux;
>> + struct mux_chip *mux_chip;
>> +
>> + mux_chip = devm_mux_chip_alloc(dev, 1, sizeof(*mux));
>> + if (IS_ERR(mux_chip))
>> + return PTR_ERR(mux_chip);
>> +
>> + mux_chip->ops = &pi3usb30532_mux_ops;
>> + mux_chip->mux[0].states = MUX_USB_STATES;
>> + mux = mux_chip_priv(mux_chip);
>> + mux->client = client;
>> +
>> + return devm_mux_chip_register(dev, mux_chip);
>> +}
>> +
>> +static const struct i2c_device_id pi3usb30532_mux_table[] = {
>> + { "pi3usb30532" },
>> + { }
>> +};
>> +MODULE_DEVICE_TABLE(i2c, pi3usb30532_mux_table);
>> +
>> +static struct i2c_driver pi3usb30532_mux_driver = {
>> + .driver = {
>> + .name = "pi3usb30532",
>> + },
>> + .probe_new = pi3usb30532_mux_probe,
>> + .id_table = pi3usb30532_mux_table,
>> +};
>> +
>> +module_i2c_driver(pi3usb30532_mux_driver);
>> +
>> +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
>> +MODULE_DESCRIPTION("Pericom PI3USB30532 Type-C mux driver");
>> +MODULE_LICENSE("GPL");
>>
>