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authorArnaldo Carvalho de Melo <acme@redhat.com>2020-08-06 14:15:47 +0300
committerArnaldo Carvalho de Melo <acme@redhat.com>2020-08-06 14:15:47 +0300
commit94fb1afb14c4f0ceb8c5508ddddac6819f662e95 (patch)
tree4988e5769dc7482caa7f441475ae31f50bbd37ef /Documentation/devicetree/bindings/mmc/mmc-pwrseq-emmc.yaml
parentc4735d990268399da9133b0ad445e488ece009ad (diff)
parent47ec5303d73ea344e84f46660fff693c57641386 (diff)
downloadlinux-94fb1afb14c4f0ceb8c5508ddddac6819f662e95.tar.xz
Mgerge remote-tracking branch 'torvalds/master' into perf/core
To sync headers, for instance, in this case tools/perf was ahead of upstream till Linus merged tip/perf/core to get the PERF_RECORD_TEXT_POKE changes: Warning: Kernel ABI header at 'tools/include/uapi/linux/perf_event.h' differs from latest version at 'include/uapi/linux/perf_event.h' diff -u tools/include/uapi/linux/perf_event.h include/uapi/linux/perf_event.h Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'Documentation/devicetree/bindings/mmc/mmc-pwrseq-emmc.yaml')
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+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mmc/mmc-pwrseq-emmc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Simple eMMC hardware reset provider binding
+
+maintainers:
+ - Ulf Hansson <ulf.hansson@linaro.org>
+
+description:
+ The purpose of this driver is to perform standard eMMC hw reset
+ procedure, as described by Jedec 4.4 specification. This procedure is
+ performed just after MMC core enabled power to the given mmc host (to
+ fix possible issues if bootloader has left eMMC card in initialized or
+ unknown state), and before performing complete system reboot (also in
+ case of emergency reboot call). The latter is needed on boards, which
+ doesn't have hardware reset logic connected to emmc card and (limited or
+ broken) ROM bootloaders are unable to read second stage from the emmc
+ card if the card is left in unknown or already initialized state.
+
+properties:
+ compatible:
+ const: mmc-pwrseq-emmc
+
+ reset-gpios:
+ minItems: 1
+ description:
+ contains a GPIO specifier. The reset GPIO is asserted
+ and then deasserted to perform eMMC card reset. To perform
+ reset procedure as described in Jedec 4.4 specification, the
+ gpio line should be defined as GPIO_ACTIVE_LOW.
+
+required:
+ - compatible
+ - reset-gpios
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ sdhci0_pwrseq {
+ compatible = "mmc-pwrseq-emmc";
+ reset-gpios = <&gpio1 12 GPIO_ACTIVE_LOW>;
+ };
+...