[PATCH 06/10] clk: mvebu: Add the xtal clock for Armada 3700 SoC

Gregory CLEMENT
2016-06-10T13:25:50Z

This clock is the parent of all the Armada 3700 clocks. It is a fixed
rate clock which depends on the gpio configuration read when resetting
the SoC.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
drivers/clk/mvebu/Kconfig | 3 ++
drivers/clk/mvebu/Makefile | 1 +
drivers/clk/mvebu/armada-37xx-xtal.c | 93 ++++++++++++++++++++++++++++++++++++
3 files changed, 97 insertions(+)
create mode 100644 drivers/clk/mvebu/armada-37xx-xtal.c

diff --git a/drivers/clk/mvebu/Kconfig b/drivers/clk/mvebu/Kconfig
index 3165da77d525..fddc8ac5faff 100644
--- a/drivers/clk/mvebu/Kconfig
+++ b/drivers/clk/mvebu/Kconfig
@@ -24,6 +24,9 @@ config ARMADA_39X_CLK
bool
select MVEBU_CLK_COMMON

+config ARMADA_37XX_CLK
+ bool
+
config ARMADA_XP_CLK
bool
select MVEBU_CLK_COMMON
diff --git a/drivers/clk/mvebu/Makefile b/drivers/clk/mvebu/Makefile
index 7172ef65693d..4257a36d0219 100644
--- a/drivers/clk/mvebu/Makefile
+++ b/drivers/clk/mvebu/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_ARMADA_370_CLK) += armada-370.o
obj-$(CONFIG_ARMADA_375_CLK) += armada-375.o
obj-$(CONFIG_ARMADA_38X_CLK) += armada-38x.o
obj-$(CONFIG_ARMADA_39X_CLK) += armada-39x.o
+obj-$(CONFIG_ARMADA_37XX_CLK) += armada-37xx-xtal.o
obj-$(CONFIG_ARMADA_XP_CLK) += armada-xp.o
obj-$(CONFIG_ARMADA_AP806_SYSCON) += ap806-system-controller.o
obj-$(CONFIG_ARMADA_CP110_SYSCON) += cp110-system-controller.o
diff --git a/drivers/clk/mvebu/armada-37xx-xtal.c b/drivers/clk/mvebu/armada-37xx-xtal.c
new file mode 100644
index 000000000000..fb051a75b2c2
--- /dev/null
+++ b/drivers/clk/mvebu/armada-37xx-xtal.c
@@ -0,0 +1,93 @@
+/*
+ * Marvell Armada 37xx SoC xtal clocks
+ *
+ * Copyright (C) 2016 Marvell
+ *
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define NB_GPIO1_LATCH 0xC
+#define XTAL_MODE BIT(31)
+
+static struct clk *xtal_clk;
+
+static int armada_3700_xtal_clock_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ const char *xtal_name = "xtal";
+ struct device_node *parent;
+ struct regmap *regmap;
+ unsigned int rate;
+ u32 reg;
+ int ret;
+
+ parent = np->parent;
+ if (!parent) {
+ dev_err(&pdev->dev, "no parrent\n");
+ return -ENODEV;
+ }
+
+ regmap = syscon_node_to_regmap(parent);
+ if (IS_ERR(regmap)) {
+ dev_err(&pdev->dev, "cannot get regmap\n");
+ return PTR_ERR(regmap);
+ }
+
+ ret = regmap_read(regmap, NB_GPIO1_LATCH, &reg);
+ if (ret) {
+ dev_err(&pdev->dev, "cannot read from regmap\n");
+ return ret;
+ }
+
+ if (reg & XTAL_MODE)
+ rate = 40000000;
+ else
+ rate = 25000000;
+
+ of_property_read_string_index(np, "clock-output-names", 0, &xtal_name);
+ xtal_clk = clk_register_fixed_rate(NULL, xtal_name, NULL, 0, rate);
+ if (IS_ERR(xtal_clk))
+ return PTR_ERR(xtal_clk);
+ of_clk_add_provider(np, of_clk_src_simple_get, xtal_clk);
+
+ return 0;
+}
+
+static int armada_3700_xtal_clock_remove(struct platform_device *pdev)
+{
+ of_clk_del_provider(pdev->dev.of_node);
+ clk_unregister_fixed_rate(xtal_clk);
+
+ return 0;
+}
+
+static const struct of_device_id armada_3700_xtal_clock_of_match[] = {
+ { .compatible = "marvell,armada-3700-xtal-clock", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, armada_3700_xtal_clock_of_match);
+
+static struct platform_driver armada_3700_xtal_clock_driver = {
+ .probe = armada_3700_xtal_clock_probe,
+ .remove = armada_3700_xtal_clock_remove,
+ .driver = {
+ .name = "marvell-armada-3700-xtal-clock",
+ .of_match_table = armada_3700_xtal_clock_of_match,
+ },
+};
+
+module_platform_driver(armada_3700_xtal_clock_driver);
+
+MODULE_AUTHOR("Gregory CLEMENT <gregory.clement@free-electrons.com>");
+MODULE_DESCRIPTION("Marvell Armada 37xx SoC xtal clocks driver");
+MODULE_LICENSE("GPL v2");
--
2.5.0