Hi Lorenzo / Benjamin,
thanks for your patch!
This is a real nice driver, I like the design of the pin database to support
this pretty complex pin controller.
Some comments and nits:
On Wed, Sep 11, 2024 at 9:51 PM Lorenzo Bianconi <lorenzo@xxxxxxxxxx> wrote:
> Introduce pinctrl driver for EN7581 SoC. Current EN7581 pinctrl driver
> supports the following functionalities:
> - pin multiplexing
> - pin pull-up, pull-down, open-drain, current strength,
> {input,output}_enable, output_{low,high}
> - gpio controller
> - irq controller
>
> Tested-by: Benjamin Larsson <benjamin.larsson@xxxxxxxxxx>
> Co-developed-by: Benjamin Larsson <benjamin.larsson@xxxxxxxxxx>
> Signed-off-by: Benjamin Larsson <benjamin.larsson@xxxxxxxxxx>
> Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
(...)
> +#include <dt-bindings/pinctrl/mt65xx.h>
> +#include <linux/bitfield.h>
Isn't just <linux/bits.h> enough for what you're using?
> +#include <linux/gpio/driver.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/kernel.h>
What do you use from kernel.h? We usually use more fingrained
headers these days.
(...)
> +#include <linux/mfd/airoha-en7581-mfd.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/of.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_platform.h>
> +#include <linux/pinctrl/consumer.h>
Why do you need the consumer header?
(...)
> +static u32 airoha_pinctrl_rmw_unlock(void __iomem *addr, u32 mask, u32 val)
> +{
> + val |= (readl(addr) & ~mask);
> + writel(val, addr);
> +
> + return val;
> +}
> +
> +#define airoha_pinctrl_set_unlock(addr, val) \
> + airoha_pinctrl_rmw_unlock((addr), 0, (val))
> +#define airoha_pinctrl_clear_unlock(addr, mask) \
> + airoha_pinctrl_rmw_unlock((addr), (mask), (0))
> +
> +static u32 airoha_pinctrl_rmw(struct airoha_pinctrl *pinctrl,
> + void __iomem *addr, u32 mask, u32 val)
> +{
> + mutex_lock(&pinctrl->mutex);
> + val = airoha_pinctrl_rmw_unlock(addr, mask, val);
> + mutex_unlock(&pinctrl->mutex);
> +
> + return val;
> +}
Thus looks like a reimplementation of regmap-mmio, can't you just use
regmap MMIO? You use it for the SCU access already...
If you persist with this solution, please use a guard:
#include <linux/cleanup.h>
guard(mutex)(&pinctrl->mutex);
And the lock will be released when you exit the function.
> +static int airoha_pinctrl_get_gpio_from_pin(struct pinctrl_dev *pctrl_dev,
> + int pin)
> +{
> + struct pinctrl_gpio_range *range;
> + int gpio;
> +
> + range = pinctrl_find_gpio_range_from_pin_nolock(pctrl_dev, pin);
> + if (!range)
> + return -EINVAL;
> +
> + gpio = pin - range->pin_base;
> + if (gpio < 0)
> + return -EINVAL;
> +
> + return gpio;
> +}
This function is just used here:
> +static int airoha_pinconf_get(struct pinctrl_dev *pctrl_dev,
> + unsigned int pin, unsigned long *config)
> +{
> + struct airoha_pinctrl *pinctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> + enum pin_config_param param = pinconf_to_config_param(*config);
> + u32 arg;
> +
> + switch (param) {
> + case PIN_CONFIG_BIAS_PULL_DOWN:
> + case PIN_CONFIG_BIAS_DISABLE:
> + case PIN_CONFIG_BIAS_PULL_UP: {
> + u32 pull_up, pull_down;
> +
> + if (airoha_pinctrl_get_pullup_conf(pinctrl, pin, &pull_up) ||
> + airoha_pinctrl_get_pulldown_conf(pinctrl, pin, &pull_down))
> + return -EINVAL;
> +
> + if (param == PIN_CONFIG_BIAS_PULL_UP &&
> + !(pull_up && !pull_down))
> + return -EINVAL;
> + else if (param == PIN_CONFIG_BIAS_PULL_DOWN &&
> + !(pull_down && !pull_up))
> + return -EINVAL;
> + else if (pull_up || pull_down)
> + return -EINVAL;
> +
> + arg = 1;
> + break;
> + }
> + case PIN_CONFIG_DRIVE_STRENGTH: {
> + u32 e2, e4;
> +
> + if (airoha_pinctrl_get_drive_e2_conf(pinctrl, pin, &e2) ||
> + airoha_pinctrl_get_drive_e4_conf(pinctrl, pin, &e4))
> + return -EINVAL;
> +
> + arg = e4 << 1 | e2;
> + break;
> + }
> + case PIN_CONFIG_DRIVE_OPEN_DRAIN:
> + if (airoha_pinctrl_get_pcie_rst_od_conf(pinctrl, pin, &arg))
> + return -EINVAL;
> + break;
> + case PIN_CONFIG_OUTPUT_ENABLE:
> + case PIN_CONFIG_INPUT_ENABLE: {
> + int gpio = airoha_pinctrl_get_gpio_from_pin(pctrl_dev, pin);
> +
> + if (gpio < 0)
> + return gpio;
> +
> + arg = airoha_pinctrl_gpio_get_direction(pinctrl, gpio);
I don't see why a pin would have to exist in a GPIO range in order to
be set as output or input?
Can't you just set up the pin as requested and not care whether
it has a corresponding GPIO range?
Is it over-reuse of the GPIO code? I'd say just set up the pin instead.
> +static int airoha_pinconf_set(struct pinctrl_dev *pctrl_dev,
> + unsigned int pin, unsigned long *configs,
> + unsigned int num_configs)
> +{
> + struct airoha_pinctrl *pinctrl = pinctrl_dev_get_drvdata(pctrl_dev);
> + int i;
> +
> + for (i = 0; i < num_configs; i++) {
> + u32 param = pinconf_to_config_param(configs[i]);
> + u32 arg = pinconf_to_config_argument(configs[i]);
> +
> + switch (param) {
> + case PIN_CONFIG_BIAS_DISABLE:
> + airoha_pinctrl_set_pulldown_conf(pinctrl, pin, 0);
> + airoha_pinctrl_set_pullup_conf(pinctrl, pin, 0);
> + break;
> + case PIN_CONFIG_BIAS_PULL_UP:
> + airoha_pinctrl_set_pulldown_conf(pinctrl, pin, 0);
> + airoha_pinctrl_set_pullup_conf(pinctrl, pin, 1);
> + break;
> + case PIN_CONFIG_BIAS_PULL_DOWN:
> + airoha_pinctrl_set_pulldown_conf(pinctrl, pin, 1);
> + airoha_pinctrl_set_pullup_conf(pinctrl, pin, 0);
> + break;
> + case PIN_CONFIG_DRIVE_STRENGTH: {
> + u32 e2 = 0, e4 = 0;
> +
> + switch (arg) {
> + case MTK_DRIVE_2mA:
> + break;
> + case MTK_DRIVE_4mA:
> + e2 = 1;
> + break;
> + case MTK_DRIVE_6mA:
> + e4 = 1;
> + break;
> + case MTK_DRIVE_8mA:
> + e2 = 1;
> + e4 = 1;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + airoha_pinctrl_set_drive_e2_conf(pinctrl, pin, e2);
> + airoha_pinctrl_set_drive_e4_conf(pinctrl, pin, e4);
> + break;
> + }
> + case PIN_CONFIG_DRIVE_OPEN_DRAIN:
> + airoha_pinctrl_set_pcie_rst_od_conf(pinctrl, pin, !!arg);
> + break;
> + case PIN_CONFIG_OUTPUT_ENABLE:
> + case PIN_CONFIG_INPUT_ENABLE:
> + case PIN_CONFIG_OUTPUT: {
> + int gpio = airoha_pinctrl_get_gpio_from_pin(pctrl_dev, pin);
> + bool input = param == PIN_CONFIG_INPUT_ENABLE;
> +
> + if (gpio < 0)
> + return gpio;
> +
> + airoha_pinctrl_gpio_set_direction(pinctrl, gpio, input);
> + if (param == PIN_CONFIG_OUTPUT)
> + airoha_pinctrl_gpio_set_value(pinctrl, gpio, !!arg);
> + break;
Dito. No need to reuse the GPIO set direction function. Make a helper
that just work on the pin instead, and perhaps the GPIO set direction
can use that instead.
> +static int airoha_pinctrl_gpio_direction_output(struct gpio_chip *chip,
> + unsigned int gpio, int value)
> +{
> + int err;
> +
> + err = pinctrl_gpio_direction_output(chip, gpio);
> + if (err)
> + return err;
> +
> + airoha_pinctrl_gpio_set(chip, gpio, value);
Hm I get a bit confused by the similarly named helpers I guess...
> +static void airoha_pinctrl_gpio_irq_unmask(struct irq_data *data)
> +{
> + u8 offset = data->hwirq % AIROHA_REG_GPIOCTRL_NUM_GPIO;
> + u8 index = data->hwirq / AIROHA_REG_GPIOCTRL_NUM_GPIO;
> + u32 mask = GENMASK(2 * offset + 1, 2 * offset);
> + struct airoha_pinctrl_gpiochip *gpiochip;
> + u32 val = BIT(2 * offset);
> + unsigned long flags;
> +
> + gpiochip = irq_data_get_irq_chip_data(data);
> + if (WARN_ON_ONCE(data->hwirq >= ARRAY_SIZE(gpiochip->irq_type)))
> + return;
> +
> + spin_lock_irqsave(&gpiochip->lock, flags);
Use a scoped guard here
guard(spinlock_irqsave)(&gpiochip->lock);
> +static void airoha_pinctrl_gpio_irq_mask(struct irq_data *data)
> +{
> + u8 offset = data->hwirq % AIROHA_REG_GPIOCTRL_NUM_GPIO;
> + u8 index = data->hwirq / AIROHA_REG_GPIOCTRL_NUM_GPIO;
> + u32 mask = GENMASK(2 * offset + 1, 2 * offset);
> + struct airoha_pinctrl_gpiochip *gpiochip;
> + unsigned long flags;
> +
> + gpiochip = irq_data_get_irq_chip_data(data);
> +
> + spin_lock_irqsave(&gpiochip->lock, flags);
Dito
> +static int airoha_pinctrl_gpio_irq_type(struct irq_data *data,
> + unsigned int type)
> +{
> + struct airoha_pinctrl_gpiochip *gpiochip;
> + unsigned long flags;
> +
> + gpiochip = irq_data_get_irq_chip_data(data);
> + if (data->hwirq >= ARRAY_SIZE(gpiochip->irq_type))
> + return -EINVAL;
> +
> + spin_lock_irqsave(&gpiochip->lock, flags);
Dito
> + girq->chip = devm_kzalloc(dev, sizeof(*girq->chip), GFP_KERNEL);
> + if (!girq->chip)
> + return -ENOMEM;
> +
> + girq->chip->name = dev_name(dev);
> + girq->chip->irq_unmask = airoha_pinctrl_gpio_irq_unmask;
> + girq->chip->irq_mask = airoha_pinctrl_gpio_irq_mask;
> + girq->chip->irq_mask_ack = airoha_pinctrl_gpio_irq_mask;
> + girq->chip->irq_set_type = airoha_pinctrl_gpio_irq_type;
> + girq->chip->flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_IMMUTABLE;
> + girq->default_type = IRQ_TYPE_NONE;
> + girq->handler = handle_simple_irq;
If the irqchip is immutable it is const and there is no point to malloc it.
Just
static const struct irq_chip airoha_gpio_irq_chip = {...
And assign it:
girq = &g->gc.irq;
gpio_irq_chip_set_chip(girq, &airoha_gpio_irq_chip);
Yours,
Linus Walleij
