Re: [PATCH v2 3/8] pinctrl: msm: Add ability for drivers to supply a reserved GPIO list
From: Ard Biesheuvel <hidden>
Date: 2019-06-07 11:10:17
Also in:
linux-arm-msm, linux-gpio, linux-i2c, linux-usb, lkml
On Fri, 7 Jun 2019 at 10:29, Lee Jones [off-list ref] wrote:
When booting MSM based platforms with Device Tree or some ACPI implementations, it is possible to provide a list of reserved pins via the 'gpio-reserved-ranges' and 'gpios' properties respectively. However some ACPI tables are not populated with this information, thus it has to come from a knowledgable device driver instead. Here we provide the MSM common driver with additional support to parse this informtion and correctly populate the widely used 'valid_mask'. Signed-off-by: Lee Jones <redacted>
I'm not sure if this is the correct approach. Presumably, on ACPI systems, all the pinctl stuff is already set up by the firmware, and so we shouldn't touch *any* pins unless they have been requested explicitly. Is there any way we can support this in the current framework?
quoted hunk ↗ jump to hunk
--- drivers/pinctrl/qcom/pinctrl-msm.c | 18 ++++++++++++++++++ drivers/pinctrl/qcom/pinctrl-msm.h | 1 + 2 files changed, 19 insertions(+)diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c index ee8119879c4c..3ac740b36508 100644 --- a/drivers/pinctrl/qcom/pinctrl-msm.c +++ b/drivers/pinctrl/qcom/pinctrl-msm.c@@ -607,8 +607,23 @@ static int msm_gpio_init_valid_mask(struct gpio_chip *chip) int ret; unsigned int len, i; unsigned int max_gpios = pctrl->soc->ngpios; + const int *reserved = pctrl->soc->reserved_gpios; u16 *tmp; + /* Driver provided reserved list overrides DT and ACPI */ + if (reserved) { + bitmap_fill(chip->valid_mask, max_gpios); + for (i = 0; reserved[i] >= 0; i++) { + if (i >= max_gpios || reserved[i] >= max_gpios) { + dev_err(pctrl->dev, "invalid list of reserved GPIOs\n"); + return -EINVAL; + } + clear_bit(reserved[i], chip->valid_mask); + } + + return 0; + } + /* The number of GPIOs in the ACPI tables */ len = ret = device_property_read_u16_array(pctrl->dev, "gpios", NULL, 0);@@ -964,6 +979,9 @@ static void msm_gpio_irq_handler(struct irq_desc *desc) static bool msm_gpio_needs_valid_mask(struct msm_pinctrl *pctrl) { + if (pctrl->soc->reserved_gpios) + return true; + return device_property_read_u16_array(pctrl->dev, "gpios", NULL, 0) > 0; }diff --git a/drivers/pinctrl/qcom/pinctrl-msm.h b/drivers/pinctrl/qcom/pinctrl-msm.h index c12048e54a6f..23b93ae92269 100644 --- a/drivers/pinctrl/qcom/pinctrl-msm.h +++ b/drivers/pinctrl/qcom/pinctrl-msm.h@@ -121,6 +121,7 @@ struct msm_pinctrl_soc_data { bool pull_no_keeper; const char *const *tiles; unsigned int ntiles; + const int *reserved_gpios; }; extern const struct dev_pm_ops msm_pinctrl_dev_pm_ops; --2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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