[U-Boot] [PATCH v5 02/14] sysreset: add syscon-reboot driver

Álvaro Fernández Rojas
2017-04-23T08:43:44Z

Add a new sysreset driver based on linux/drivers/power/reset/syscon-reboot.c,
which provides a generic driver for platforms that only require writing a mask
to a regmap offset.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
---
v5: No chnages.
v4: Rebased.
v3: Introduce changes suggested by Simon Glass:
- Add missing driver description.
- Alphabetically order includes.
- Add priv struct to store regmap during probe.
- Cosmetic fixes.
v2: No changes.

drivers/sysreset/Kconfig | 8 ++++
drivers/sysreset/Makefile | 1 +
drivers/sysreset/sysreset_syscon.c | 76 ++++++++++++++++++++++++++++++++++++++
3 files changed, 85 insertions(+)
create mode 100644 drivers/sysreset/sysreset_syscon.c

diff --git a/drivers/sysreset/Kconfig b/drivers/sysreset/Kconfig
index 9664630..b2f7464 100644
--- a/drivers/sysreset/Kconfig
+++ b/drivers/sysreset/Kconfig
@@ -23,4 +23,12 @@ config SYSRESET_PSCI
must be running on your system.

endif
+
+config SYSRESET_SYSCON
+ bool "Enable support for mfd syscon reboot driver"
+ select REGMAP
+ select SYSCON
+ help
+ Reboot support for generic SYSCON mapped register reset.
+
endmenu
diff --git a/drivers/sysreset/Makefile b/drivers/sysreset/Makefile
index 7bb8406..bd352e7 100644
--- a/drivers/sysreset/Makefile
+++ b/drivers/sysreset/Makefile
@@ -6,6 +6,7 @@

obj-$(CONFIG_SYSRESET) += sysreset-uclass.o
obj-$(CONFIG_SYSRESET_PSCI) += sysreset_psci.o
+obj-$(CONFIG_SYSRESET_SYSCON) += sysreset_syscon.o

ifndef CONFIG_SPL_BUILD
obj-$(CONFIG_ROCKCHIP_RK3036) += sysreset_rk3036.o
diff --git a/drivers/sysreset/sysreset_syscon.c b/drivers/sysreset/sysreset_syscon.c
new file mode 100644
index 0000000..adfddb4
--- /dev/null
+++ b/drivers/sysreset/sysreset_syscon.c
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
+ *
+ * Derived from linux/drivers/power/reset/syscon-reboot.c:
+ * Copyright (C) 2013, Applied Micro Circuits Corporation
+ * Author: Feng Kan <fkan@apm.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <regmap.h>
+#include <sysreset.h>
+#include <syscon.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct syscon_reboot_priv {
+ struct regmap *regmap;
+ unsigned int offset;
+ unsigned int mask;
+};
+
+static int syscon_reboot_request(struct udevice *dev, enum sysreset_t type)
+{
+ struct syscon_reboot_priv *priv = dev_get_priv(dev);
+
+ regmap_write(priv->regmap, priv->offset, priv->mask);
+
+ return -EINPROGRESS;
+}
+
+static struct sysreset_ops syscon_reboot_ops = {
+ .request = syscon_reboot_request,
+};
+
+int syscon_reboot_probe(struct udevice *dev)
+{
+ struct udevice *syscon;
+ struct syscon_reboot_priv *priv = dev_get_priv(dev);
+ int err;
+
+ err = uclass_get_device_by_phandle(UCLASS_SYSCON, dev,
+ "regmap", &syscon);
+ if (err) {
+ error("unable to find syscon device\n");
+ return err;
+ }
+
+ priv->regmap = syscon_get_regmap(syscon);
+ if (!priv->regmap) {
+ error("unable to find regmap\n");
+ return -ENODEV;
+ }
+
+ priv->offset = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev), "offset", 0);
+ priv->mask = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev), "mask", 0);
+
+ return 0;
+}
+
+static const struct udevice_id syscon_reboot_ids[] = {
+ { .compatible = "syscon-reboot" },
+ { /* sentinel */ }
+};
+
+U_BOOT_DRIVER(syscon_reboot) = {
+ .name = "syscon_reboot",
+ .id = UCLASS_SYSRESET,
+ .of_match = syscon_reboot_ids,
+ .probe = syscon_reboot_probe,
+ .priv_auto_alloc_size = sizeof(struct syscon_reboot_priv),
+ .ops = &syscon_reboot_ops,
+};
--
2.1.4