Re: [PATCH v3 5/5] pinctrl: lochnagar: Add support for the Cirrus Logic Lochnagar

Linus Walleij
2018-10-30T13:04:35Z

On Fri, Oct 19, 2018 at 11:50 AM Charles Keepax
<ckeepax@opensource.cirrus.com> wrote:

> Lochnagar is an evaluation and development board for Cirrus
> Logic Smart CODEC and Amp devices. It allows the connection of
> most Cirrus Logic devices on mini-cards, as well as allowing
> connection of various application processor systems to provide a
> full evaluation platform. This driver supports the board
> controller chip on the Lochnagar board.
>
> Lochnagar provides many pins which can generally be used for an
> audio function such as an AIF or a PDM interface, but also as
> GPIOs.
>
> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
> ---
>
> Changes since v2:
> - Updated aif-master/aif-slave to use a vendor prefix
> - Correctly get and put of_node pointer in probe/remove

Looks better and better! Some comments, probably not the last comments:

> +#include <linux/err.h>
> +#include <linux/errno.h>
> +#include <linux/gpio/driver.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/pinctrl/pinctrl.h>
> +#include <linux/pinctrl/pinmux.h>
> +#include <linux/pinctrl/pinconf.h>
> +#include <linux/pinctrl/pinconf-generic.h>

#include <linux/bits.h>

> +struct lochnagar_aif {
> + const char name[16];
> +
> + unsigned int pins[4];
> +
> + unsigned int src_reg;

u32?

> + unsigned int src_mask;

u32?

> +
> + unsigned int ctrl_reg;

u32?

> + unsigned int ena_mask;

u32?

> + unsigned int master_mask;

u32?

> +struct lochnagar_func {
> + const char * const name;
> +
> + enum lochnagar_func_type type;
> +
> + int op;

unsigned int? u32?

Looks like u8 actually.

> +struct lochnagar_group {
> + const char * const name;
> +
> + enum lochnagar_func_type type;
> +
> + const unsigned int *pins;
> + int npins;

unsigned int npins?

> +struct lochnagar_func_groups {
> + const char **groups;
> + int ngroups;

unsigned int ngroups?

> +struct lochnagar_pin_priv {
> + struct lochnagar *lochnagar;
> + struct device *dev;
> +
> + const struct lochnagar_func *funcs;
> + int nfuncs;
> +
> + const struct pinctrl_pin_desc *pins;
> + int npins;
> +
> + const struct lochnagar_group *groups;
> + int ngroups;
> +
> + struct lochnagar_func_groups func_groups[LN_FTYPE_COUNT];
> +
> + struct gpio_chip gpio_chip;
> +};

I bet some of these should be unsigned as well.

> +static const struct pinconf_generic_params lochnagar_dt_params[] = {
> + {"cirrus,aif-master", PIN_CONFIG_AIFMASTER, 0},
> + {"cirrus,aif-slave", PIN_CONFIG_AIFSLAVE, 0},
> +};

I guess these are documented in the device tree bindings.

They look suspciously like muxing but I guess it is explained
there.

> +static void lochnagar_gpio_set(struct gpio_chip *chip,
> + unsigned int offset, int value)
> +{
> + struct lochnagar_pin_priv *priv = gpiochip_get_data(chip);
> + struct lochnagar *lochnagar = priv->lochnagar;
> + const struct lochnagar_pin *pin = priv->pins[offset].drv_data;
> + int ret;
> +
> + value = !!value;

value = value ? BIT(pin->shift) : 0;

> + dev_dbg(priv->dev, "Set GPIO %s to %s\n",
> + pin->name, value ? "high" : "low");
> +
> + switch (pin->type) {
> + case LN_PTYPE_MUX:
> + value |= LN2_OP_GPIO;
> +
> + ret = lochnagar_pin_set_mux(priv, pin, value);
> + break;
> + case LN_PTYPE_GPIO:
> + if (pin->invert)
> + value = !value;
> +
> + ret = regmap_update_bits(lochnagar->regmap, pin->reg,
> + 0x1 << pin->shift,

BIT(pin->shift)

> + value << pin->shift);

Just value provided you used the construction above
to construct it.

Yours,
Linus Walleij