Re: [PATCH v2 09/32] gpio: qcom_pmic: add a quirk to skip GPIO configuration

[Neil Armstrong]

On 19/12/2023 17:04, Caleb Connolly wrote:

Some platforms hard reset when attempting to configure PMIC GPIOs. Add
support for quirks specified in match data with a single quirk to skip
this configuration. We rely on the GPIO already be configured correctly,
which is always the case for volume up (the only current user of these
GPIOs).

Do you know why this happens in u-boot and not in Linux ?

Signed-off-by: Caleb Connolly <caleb.conno...@linaro.org>
---
  drivers/gpio/qcom_pmic_gpio.c | 18 ++++++++++++++++--
  1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/qcom_pmic_gpio.c b/drivers/gpio/qcom_pmic_gpio.c
index 2a4fef8d28cb..198cd84bc31e 100644
--- a/drivers/gpio/qcom_pmic_gpio.c
+++ b/drivers/gpio/qcom_pmic_gpio.c
@@ -64,6 +64,15 @@
  #define REG_EN_CTL             0x46
  #define REG_EN_CTL_ENABLE      (1 << 7)

+/**

+ * pmic_gpio_match_data - platform specific configuration
+ *
+ * @PMIC_MATCH_READONLY: treat all GPIOs as readonly, don't attempt to 
configure them
+ */
+enum pmic_gpio_quirks {
+       QCOM_PMIC_QUIRK_READONLY = (1 << 0),
+};
+
  struct qcom_gpio_bank {
        uint32_t pid; /* Peripheral ID on SPMI bus */
        bool     lv_mv_type; /* If subtype is GPIO_LV(0x10) or GPIO_MV(0x11) */
@@ -75,7 +84,12 @@ static int qcom_gpio_set_direction(struct udevice *dev, 
unsigned offset,
        struct qcom_gpio_bank *priv = dev_get_priv(dev);
        uint32_t gpio_base = priv->pid + REG_OFFSET(offset);
        uint32_t reg_ctl_val;
-       int ret;
+       ulong quirks = dev_get_driver_data(dev);
+       int ret = 0;
+
+       /* Some PMICs don't like their GPIOs being configured */
+       if (quirks & QCOM_PMIC_QUIRK_READONLY)
+               return 0;

/* Disable the GPIO */

        ret = pmic_clrsetbits(dev->parent, gpio_base + REG_EN_CTL,
@@ -304,7 +318,7 @@ static int qcom_gpio_of_to_plat(struct udevice *dev)
  static const struct udevice_id qcom_gpio_ids[] = {
        { .compatible = "qcom,pm8916-gpio" },
        { .compatible = "qcom,pm8994-gpio" }, /* 22 GPIO's */
-       { .compatible = "qcom,pm8998-gpio" },
+       { .compatible = "qcom,pm8998-gpio", .data = QCOM_PMIC_QUIRK_READONLY },
        { .compatible = "qcom,pms405-gpio" },
        { }
  };