Re: [PATCH V1] pinctrl: qcom: spmi-gpio: Add support for qcom,gpios-disallowed property

From: Shawn Guo
Date: Mon Aug 28 2017 - 10:55:12 EST


On Wed, Jul 19, 2017 at 03:17:07PM +0800, fenglinw@xxxxxxxxxxxxxx wrote:
> From: Fenglin Wu <fenglinw@xxxxxxxxxxxxxx>
>
> Add support for qcom,gpios-disallowed property which is used to exclude
> PMIC GPIOs not owned by the APSS processor from the pinctrl device.

If I understand it correctly, whether PMIC GPIOs is owned by APSS or not
can be configured by firmware. If that's true, I do not think we should
have this qcom,gpios-disallowed thing in device tree, which is supposed
to describe hardware not something software configurable.

Shawn

> Signed-off-by: Fenglin Wu <fenglinw@xxxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/pinctrl/qcom,pmic-gpio.txt | 12 ++
> drivers/pinctrl/qcom/pinctrl-spmi-gpio.c | 202 +++++++++++++++++----
> 2 files changed, 176 insertions(+), 38 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,pmic-gpio.txt b/Documentation/devicetree/bindings/pinctrl/qcom,pmic-gpio.txt
> index 8d893a8..435efe8 100644
> --- a/Documentation/devicetree/bindings/pinctrl/qcom,pmic-gpio.txt
> +++ b/Documentation/devicetree/bindings/pinctrl/qcom,pmic-gpio.txt
> @@ -43,6 +43,17 @@ PMIC's from Qualcomm.
> the first cell will be used to define gpio number and the
> second denotes the flags for this gpio
>
> +- qcom,gpios-disallowed:
> + Usage: optional
> + Value type: <prop-encoded-array>
> + Definition: Array of the GPIO hardware numbers corresponding to GPIOs
> + which the APSS processor is not allowed to configure.
> + The hardware numbers are indexed from 1.
> + The interrupt resources for these GPIOs must not be defined
> + in "interrupts" and "interrupt-names" properties.
> + GPIOs defined in this array won't be registered as pins
> + in the pinctrl device or gpios in the gpio chip.
> +
> Please refer to ../gpio/gpio.txt and ../interrupt-controller/interrupts.txt for
> a general description of GPIO and interrupt bindings.
>
> @@ -206,6 +217,7 @@ Example:
>
> gpio-controller;
> #gpio-cells = <2>;
> + qcom,gpios-disallowed = <1 20>;
>
> pm8921_gpio_keys: gpio-keys {
> volume-keys {
> diff --git a/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c b/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
> index 664b641..74821af 100644
> --- a/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
> +++ b/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
> @@ -96,6 +96,7 @@
> * struct pmic_gpio_pad - keep current GPIO settings
> * @base: Address base in SPMI device.
> * @irq: IRQ number which this GPIO generate.
> + * @gpio_idx: The index in GPIO's hardware number space (1-based)
> * @is_enabled: Set to false when GPIO should be put in high Z state.
> * @out_value: Cached pin output value
> * @have_buffer: Set to true if GPIO output could be configured in push-pull,
> @@ -112,6 +113,7 @@
> struct pmic_gpio_pad {
> u16 base;
> int irq;
> + int gpio_idx;
> bool is_enabled;
> bool out_value;
> bool have_buffer;
> @@ -130,6 +132,7 @@ struct pmic_gpio_state {
> struct regmap *map;
> struct pinctrl_dev *ctrl;
> struct gpio_chip chip;
> + const char **gpio_groups;
> };
>
> static const struct pinconf_generic_params pmic_gpio_bindings[] = {
> @@ -231,7 +234,9 @@ static int pmic_gpio_get_function_groups(struct pinctrl_dev *pctldev,
> const char *const **groups,
> unsigned *const num_qgroups)
> {
> - *groups = pmic_gpio_groups;
> + struct pmic_gpio_state *state = pinctrl_dev_get_drvdata(pctldev);
> +
> + *groups = state->gpio_groups;
> *num_qgroups = pctldev->desc->npins;
> return 0;
> }
> @@ -455,7 +460,7 @@ static void pmic_gpio_config_dbg_show(struct pinctrl_dev *pctldev,
>
> pad = pctldev->desc->pins[pin].drv_data;
>
> - seq_printf(s, " gpio%-2d:", pin + PMIC_GPIO_PHYSICAL_OFFSET);
> + seq_printf(s, " gpio%-2d:", pad->gpio_idx);
>
> val = pmic_gpio_read(state, pad, PMIC_GPIO_REG_EN_CTL);
>
> @@ -546,13 +551,29 @@ static int pmic_gpio_of_xlate(struct gpio_chip *chip,
> const struct of_phandle_args *gpio_desc,
> u32 *flags)
> {
> + int i;
> + struct pmic_gpio_state *state = gpiochip_get_data(chip);
> + struct pinctrl_desc *desc = state->ctrl->desc;
> + struct pmic_gpio_pad *pad;
> +
> if (chip->of_gpio_n_cells < 2)
> return -EINVAL;
>
> if (flags)
> *flags = gpio_desc->args[1];
>
> - return gpio_desc->args[0] - PMIC_GPIO_PHYSICAL_OFFSET;
> + for (i = 0; i < chip->ngpio; i++) {
> + pad = desc->pins[i].drv_data;
> + if (pad->gpio_idx == gpio_desc->args[0]) {
> + dev_dbg(state->dev, "gpio%-2d xlate to pin%-2d\n",
> + gpio_desc->args[0], i);
> + return i;
> + }
> + }
> +
> + dev_err(state->dev, "Couldn't find pin for gpio %d\n",
> + gpio_desc->args[0]);
> + return -ENODEV;
> }
>
> static int pmic_gpio_to_irq(struct gpio_chip *chip, unsigned pin)
> @@ -688,43 +709,124 @@ static int pmic_gpio_probe(struct platform_device *pdev)
> struct pinctrl_desc *pctrldesc;
> struct pmic_gpio_pad *pad, *pads;
> struct pmic_gpio_state *state;
> - int ret, npins, i;
> - u32 reg;
> + int ret, npins, ngpios, i, j, pin_idx;
> + int disallowed_count = 0;
> + u32 reg[2], start, size;
> + u32 *disallowed = NULL;
>
> - ret = of_property_read_u32(dev->of_node, "reg", &reg);
> + ret = of_property_read_u32_array(dev->of_node, "reg", reg, 2);
> if (ret < 0) {
> - dev_err(dev, "missing base address");
> + dev_err(dev, "reg property reading failed\n");
> return ret;
> }
> + start = reg[0];
> + size = reg[1];
> +
> + ngpios = size / PMIC_GPIO_ADDRESS_RANGE;
> + if (ngpios == 0) {
> + dev_err(dev, "no gpios assigned\n");
> + return -ENODEV;
> + }
>
> - npins = platform_irq_count(pdev);
> - if (!npins)
> + if (ngpios > ARRAY_SIZE(pmic_gpio_groups)) {
> + dev_err(dev, "reg property defines %d gpios, but only %d are allowed\n",
> + ngpios, (int)ARRAY_SIZE(pmic_gpio_groups));
> return -EINVAL;
> - if (npins < 0)
> - return npins;
> + }
> +
> + if (of_find_property(dev->of_node, "qcom,gpios-disallowed",
> + &disallowed_count)) {
> + disallowed_count /= sizeof(u32);
> + if (disallowed_count == 0) {
> + dev_err(dev, "No data in gpios-disallowed\n");
> + return -EINVAL;
> + }
>
> - BUG_ON(npins > ARRAY_SIZE(pmic_gpio_groups));
> + disallowed = kcalloc(disallowed_count, sizeof(u32), GFP_KERNEL);
> + if (disallowed == NULL)
> + return -ENOMEM;
> +
> + ret = of_property_read_u32_array(dev->of_node,
> + "qcom,gpios-disallowed",
> + disallowed, disallowed_count);
> + if (ret < 0) {
> + dev_err(dev, "qcom,gpios-disallowed property reading failed, ret=%d\n",
> + ret);
> + goto err_free;
> + }
> +
> + for (i = 0; i < disallowed_count; i++) {
> + if (disallowed[i] >= ngpios + PMIC_GPIO_PHYSICAL_OFFSET
> + || disallowed[i] < PMIC_GPIO_PHYSICAL_OFFSET) {
> + dev_err(dev, "invalid gpio = %d specified in qcom,gpios-disallowed, supported values: %d to %d\n",
> + disallowed[i],
> + PMIC_GPIO_PHYSICAL_OFFSET,
> + ngpios - 1 + PMIC_GPIO_PHYSICAL_OFFSET);
> + ret = -EINVAL;
> + goto err_free;
> + }
> + for (j = 0; j < i; j++) {
> + if (disallowed[i] == disallowed[j]) {
> + dev_err(dev, "duplicate gpio = %d listed in qcom,gpios-disallowed\n",
> + disallowed[i]);
> + ret = -EINVAL;
> + goto err_free;
> + }
> + }
> + dev_dbg(dev, "gpio %d NOT supported\n", disallowed[i]);
> + }
> + } else {
> + disallowed_count = 0;
> + }
> +
> + npins = ngpios - disallowed_count;
> + if (npins <= 0) {
> + dev_err(dev, "No pins assigned\n");
> + ret = -ENODEV;
> + goto err_free;
> + }
> + if (platform_irq_count(pdev) != npins) {
> + dev_err(dev, "%d IRQs defined but %d expected\n",
> + platform_irq_count(pdev), npins);
> + ret = -EINVAL;
> + goto err_free;
> + }
>
> state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
> - if (!state)
> - return -ENOMEM;
> + if (!state) {
> + ret = -ENOMEM;
> + goto err_free;
> + }
>
> platform_set_drvdata(pdev, state);
>
> state->dev = &pdev->dev;
> state->map = dev_get_regmap(dev->parent, NULL);
>
> + state->gpio_groups = devm_kcalloc(dev, sizeof(*state->gpio_groups),
> + npins, GFP_KERNEL);
> + if (!state->gpio_groups) {
> + ret = -ENOMEM;
> + goto err_free;
> + }
> +
> pindesc = devm_kcalloc(dev, npins, sizeof(*pindesc), GFP_KERNEL);
> - if (!pindesc)
> - return -ENOMEM;
> + if (!pindesc) {
> + ret = -ENOMEM;
> + goto err_free;
> + }
>
> pads = devm_kcalloc(dev, npins, sizeof(*pads), GFP_KERNEL);
> - if (!pads)
> - return -ENOMEM;
> + if (!pads) {
> + ret = -ENOMEM;
> + goto err_free;
> + }
>
> pctrldesc = devm_kzalloc(dev, sizeof(*pctrldesc), GFP_KERNEL);
> - if (!pctrldesc)
> - return -ENOMEM;
> + if (!pctrldesc) {
> + ret = -ENOMEM;
> + goto err_free;
> + }
>
> pctrldesc->pctlops = &pmic_gpio_pinctrl_ops;
> pctrldesc->pmxops = &pmic_gpio_pinmux_ops;
> @@ -738,22 +840,42 @@ static int pmic_gpio_probe(struct platform_device *pdev)
> #ifdef CONFIG_DEBUG_FS
> pctrldesc->custom_conf_items = pmic_conf_items;
> #endif
> + for (pin_idx = 0, i = 0; i < ngpios; i++) {
> + for (j = 0; j < disallowed_count; j++) {
> + if (i + PMIC_GPIO_PHYSICAL_OFFSET == disallowed[j])
> + break;
> + }
> + if (j != disallowed_count)
> + continue;
>
> - for (i = 0; i < npins; i++, pindesc++) {
> - pad = &pads[i];
> + pad = &pads[pin_idx];
> pindesc->drv_data = pad;
> - pindesc->number = i;
> + pindesc->number = pin_idx;
> pindesc->name = pmic_gpio_groups[i];
>
> - pad->irq = platform_get_irq(pdev, i);
> - if (pad->irq < 0)
> - return pad->irq;
> + pad->gpio_idx = i + PMIC_GPIO_PHYSICAL_OFFSET;
> + pad->irq = platform_get_irq(pdev, pin_idx);
> + if (pad->irq < 0) {
> + dev_err(state->dev,
> + "failed to get irq for gpio %d (pin %d), ret=%d\n",
> + pad->gpio_idx, pin_idx, pad->irq);
> + ret = pad->irq;
> + goto err_free;
> + }
> + /* Every pin is a group */
> + state->gpio_groups[pin_idx] = pmic_gpio_groups[i];
>
> - pad->base = reg + i * PMIC_GPIO_ADDRESS_RANGE;
> + pad->base = start + i * PMIC_GPIO_ADDRESS_RANGE;
>
> ret = pmic_gpio_populate(state, pad);
> - if (ret < 0)
> - return ret;
> + if (ret < 0) {
> + dev_err(state->dev,
> + "failed to populate gpio %d, ret=%d\n",
> + i, ret);
> + goto err_free;
> + }
> + pindesc++;
> + pin_idx++;
> }
>
> state->chip = pmic_gpio_gpio_template;
> @@ -765,25 +887,29 @@ static int pmic_gpio_probe(struct platform_device *pdev)
> state->chip.can_sleep = false;
>
> state->ctrl = devm_pinctrl_register(dev, pctrldesc, state);
> - if (IS_ERR(state->ctrl))
> - return PTR_ERR(state->ctrl);
> + if (IS_ERR(state->ctrl)) {
> + ret = PTR_ERR(state->ctrl);
> + dev_err(state->dev, "failed to register pinctrl device, ret=%d\n",
> + ret);
> + goto err_free;
> + }
>
> ret = gpiochip_add_data(&state->chip, state);
> if (ret) {
> - dev_err(state->dev, "can't add gpio chip\n");
> - return ret;
> + dev_err(state->dev, "can't add gpio chip, ret=%d\n", ret);
> + goto err_free;
> }
>
> ret = gpiochip_add_pin_range(&state->chip, dev_name(dev), 0, 0, npins);
> if (ret) {
> - dev_err(dev, "failed to add pin range\n");
> - goto err_range;
> + dev_err(dev, "failed to add pin range\n, ret=%d\n", ret);
> + gpiochip_remove(&state->chip);
> + goto err_free;
> }
>
> - return 0;
> +err_free:
> + kfree(disallowed);
>
> -err_range:
> - gpiochip_remove(&state->chip);
> return ret;
> }
>
> --
> Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project.
>