Messages in this thread Patch in this message |  | | Date | Wed, 03 Oct 2018 05:38:24 -0700 | From | Sodagudi Prasad <> | Subject | protected pins and debugfs |
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Hi All,
This is regarding the protected pins configuration reading and printing from non-secure operating systems. GPIO framework is checking whether pin is in use(flag FLAG_REQUESTED) or not in gpiolib_dbg_show().
If GPIO chip drivers are overriding the dbg_show callback, drivers are not checking whether a pin is really in use or not to print configuration details. if (chip->dbg_show) chip->dbg_show(s, chip); else gpiolib_dbg_show(s, gdev);
I think, reserved-gpio-ranges solution may move the problem to dts settings maintenance as they change from platform to platform. https://lore.kernel.org/patchwork/patch/878107/ https://lore.kernel.org/patchwork/patch/878106/ https://lore.kernel.org/patchwork/patch/878109/
Can we use a simple/common solution like below? It will check whether a pin is in use or not before printing configuration data with the help of gpiochip_is_requested().
index fef0970..2ca1440 100644 --- a/drivers/pinctrl/qcom/pinctrl-msm.c +++ b/drivers/pinctrl/qcom/pinctrl-msm.c @@ -579,16 +579,20 @@ static void msm_gpio_dbg_show_one(struct seq_file *s, seq_printf(s, " %-8s: %-3s %d", g->name, is_out ? "out" : "in", func); seq_printf(s, " %dmA", msm_regval_to_drive(drive)); seq_printf(s, " %s", pulls[pull]); + seq_puts(s, "\n"); }
static void msm_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) { unsigned gpio = chip->base; unsigned i; + const char *label;
for (i = 0; i < chip->ngpio; i++, gpio++) { + label = gpiochip_is_requested(chip, i); + if (!label) + continue; msm_gpio_dbg_show_one(s, NULL, chip, i, gpio); - seq_puts(s, "\n"); } }
-Thanks, Prasad -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, Linux Foundation Collaborative Project
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