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

Peter Rosin
2017-09-04T11:20:02Z

Hi!

One comment inline...

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");
>