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authorSascha Hauer <s.hauer@pengutronix.de>2018-06-11 22:36:27 +0200
committerSascha Hauer <s.hauer@pengutronix.de>2018-06-11 22:36:27 +0200
commit2f669d37b0d5cbb898540ccf941e55d122077200 (patch)
tree0297c3e670b4d1e68696e4ce73597a36a78c29a5 /drivers
parent242607ca36c6f99c73c9588feeba8aed650fa25f (diff)
parent96aff45747a1cec76ff26778e94884ae2ce572b9 (diff)
downloadbarebox-2f669d37b0d5cbb898540ccf941e55d122077200.tar.gz
barebox-2f669d37b0d5cbb898540ccf941e55d122077200.tar.xz
Merge branch 'for-next/clk'
Diffstat (limited to 'drivers')
-rw-r--r--drivers/clk/Makefile2
-rw-r--r--drivers/clk/clk-gpio.c130
-rw-r--r--drivers/clk/clk.c9
3 files changed, 137 insertions, 4 deletions
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 55ac9535a5..cd4026c944 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -1,7 +1,7 @@
obj-$(CONFIG_COMMON_CLK) += clk.o clk-fixed.o clk-divider.o clk-fixed-factor.o \
clk-mux.o clk-gate.o clk-composite.o \
clk-fractional-divider.o clk-conf.o \
- clk-gate-shared.o
+ clk-gate-shared.o clk-gpio.o
obj-$(CONFIG_CLKDEV_LOOKUP) += clkdev.o
obj-$(CONFIG_ARCH_MVEBU) += mvebu/
diff --git a/drivers/clk/clk-gpio.c b/drivers/clk/clk-gpio.c
new file mode 100644
index 0000000000..352c85dfe2
--- /dev/null
+++ b/drivers/clk/clk-gpio.c
@@ -0,0 +1,130 @@
+/*
+ * clk-gpio.c - clock that can be enabled and disabled via GPIO output
+ * Based on Linux clk support
+ *
+ * Copyright (c) 2018 Nikita Yushchenko <nikita.yoush@cogentembedded.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <common.h>
+#include <malloc.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <gpio.h>
+#include <of_gpio.h>
+#include <init.h>
+
+struct clk_gpio {
+ struct clk clk;
+ const char *parent;
+ int gpio;
+};
+#define to_clk_gpio(_clk) container_of(_clk, struct clk_gpio, clk)
+
+static int clk_gpio_enable(struct clk *clk)
+{
+ struct clk_gpio *clk_gpio = to_clk_gpio(clk);
+
+ gpio_set_active(clk_gpio->gpio, true);
+ return 0;
+}
+
+static void clk_gpio_disable(struct clk *clk)
+{
+ struct clk_gpio *clk_gpio = to_clk_gpio(clk);
+
+ gpio_set_active(clk_gpio->gpio, false);
+}
+
+static int clk_gpio_is_enabled(struct clk *clk)
+{
+ struct clk_gpio *clk_gpio = to_clk_gpio(clk);
+
+ return gpio_is_active(clk_gpio->gpio);
+}
+
+static struct clk_ops clk_gpio_ops = {
+ .set_rate = clk_parent_set_rate,
+ .round_rate = clk_parent_round_rate,
+ .enable = clk_gpio_enable,
+ .disable = clk_gpio_disable,
+ .is_enabled = clk_gpio_is_enabled,
+};
+
+static int of_gpio_clk_setup(struct device_node *node)
+{
+ struct clk_gpio *clk_gpio;
+ enum of_gpio_flags of_flags;
+ unsigned long flags;
+ int ret;
+
+ clk_gpio = xzalloc(sizeof(*clk_gpio));
+ if (!clk_gpio)
+ return -ENOMEM;
+
+ clk_gpio->parent = of_clk_get_parent_name(node, 0);
+ if (!clk_gpio->parent) {
+ ret = -EINVAL;
+ goto no_parent;
+ }
+
+ clk_gpio->clk.ops = &clk_gpio_ops;
+ clk_gpio->clk.parent_names = &clk_gpio->parent;
+ clk_gpio->clk.num_parents = 1;
+
+ clk_gpio->clk.name = node->name;
+ of_property_read_string(node, "clock-output-names",
+ &clk_gpio->clk.name);
+
+ ret = of_get_named_gpio_flags(node, "enable-gpios", 0,
+ &of_flags);
+ if (ret >= 0 && !gpio_is_valid(ret))
+ ret = -EINVAL;
+ if (ret < 0)
+ goto no_gpio;
+ clk_gpio->gpio = ret;
+
+ flags = GPIOF_OUT_INIT_ACTIVE;
+ if (of_flags & OF_GPIO_ACTIVE_LOW)
+ flags |= GPIOF_ACTIVE_LOW;
+ ret = gpio_request_one(clk_gpio->gpio, flags, clk_gpio->clk.name);
+ if (ret)
+ goto no_request;
+
+ ret = clk_register(&clk_gpio->clk);
+ if (ret)
+ goto no_register;
+
+ return of_clk_add_provider(node, of_clk_src_simple_get, &clk_gpio->clk);
+
+no_register:
+ gpio_free(clk_gpio->gpio);
+no_request:
+no_gpio:
+no_parent:
+ free(clk_gpio);
+ return ret;
+}
+
+/* Can't use OF_CLK_DECLARE due to need to run after GPIOcontrollers have
+ * registrered */
+
+static const struct of_device_id clk_gpio_device_id[] = {
+ { .compatible = "gpio-gate-clock", .data = of_gpio_clk_setup, },
+ {}
+};
+
+static int clk_gpio_init(void)
+{
+ return of_clk_init(NULL, clk_gpio_device_id);
+}
+coredevice_initcall(clk_gpio_init);
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 5bb147eee0..24759b45bb 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -22,6 +22,7 @@
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/clk/clk-conf.h>
+#include <pinctrl.h>
static LIST_HEAD(clks);
@@ -596,10 +597,12 @@ int of_clk_init(struct device_node *root, const struct of_device_id *matches)
list_for_each_entry_safe(clk_provider, next,
&clk_provider_list, node) {
- if (force || parent_ready(clk_provider->np)) {
+ struct device_node *np = clk_provider->np;
+ if (force || parent_ready(np)) {
- clk_provider->clk_init_cb(clk_provider->np);
- of_clk_set_defaults(clk_provider->np, true);
+ of_pinctrl_select_state_default(np);
+ clk_provider->clk_init_cb(np);
+ of_clk_set_defaults(np, true);
list_del(&clk_provider->node);
free(clk_provider);