[PATCH V2] clk: hi6220: Add the hi655x's pmic clock

Daniel Lezcano
2017-04-08T20:30:12Z

The hi655x multi function device is a PMIC providing regulators.

The PMIC also provides a clock for the WiFi and the Bluetooth, let's implement
this clock in order to add it in the hi655x MFD and allow proper wireless
initialization.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---

Changelog:

V2:
- Added COMPILE_TEST option, compiled on x86
- Removed useless parenthesis
- Used of_clk_hw_simple_get() instead of deref dance
- Do bailout if the clock-names is not specified
- Rollback on error
- Folded mfd line change and binding
- Added #clock-cells binding documentation
- Added #clock-cells in the DT

V1: initial post
---
---
.../devicetree/bindings/mfd/hisilicon,hi655x.txt | 6 +
arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts | 1 +
drivers/clk/Kconfig | 8 ++
drivers/clk/Makefile | 1 +
drivers/clk/clk-hi655x.c | 140 +++++++++++++++++++++
drivers/mfd/hi655x-pmic.c | 3 +-
6 files changed, 158 insertions(+), 1 deletion(-)
create mode 100644 drivers/clk/clk-hi655x.c

diff --git a/Documentation/devicetree/bindings/mfd/hisilicon,hi655x.txt b/Documentation/devicetree/bindings/mfd/hisilicon,hi655x.txt
index 0548569..194e2a9fd 100644
--- a/Documentation/devicetree/bindings/mfd/hisilicon,hi655x.txt
+++ b/Documentation/devicetree/bindings/mfd/hisilicon,hi655x.txt
@@ -16,6 +16,11 @@ Required properties:
- reg: Base address of PMIC on Hi6220 SoC.
- interrupt-controller: Hi655x has internal IRQs (has own IRQ domain).
- pmic-gpios: The GPIO used by PMIC IRQ.
+- #clock-cells: From common clock binding; shall be set to 0
+
+Optional properties:
+- clock-output-names: From common clock binding to override the
+ default output clock name

Example:
pmic: pmic at f8000000 {
@@ -24,4 +29,5 @@ Example:
interrupt-controller;
#interrupt-cells = <2>;
pmic-gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
+ clock-cells = <0>;
}
diff --git a/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts b/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
index dba3c13..bb9afb1 100644
--- a/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
+++ b/arch/arm64/boot/dts/hisilicon/hi6220-hikey.dts
@@ -328,6 +328,7 @@
interrupt-controller;
#interrupt-cells = <2>;
pmic-gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
+ #clock-cells = <0>;

regulators {
ldo2: LDO2 {
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 9356ab4..36cfea3 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -47,6 +47,14 @@ config COMMON_CLK_RK808
clocked at 32KHz each. Clkout1 is always on, Clkout2 can off
by control register.

+config COMMON_CLK_HI655X
+ tristate "Clock driver for Hi655x"
+ depends on MFD_HI655X_PMIC || COMPILE_TEST
+ ---help---
+ This driver supports the hi655x PMIC clock. This
+ multi-function device has one fixed-rate oscillator, clocked
+ at 32KHz.
+
config COMMON_CLK_SCPI
tristate "Clock driver controlled via SCPI interface"
depends on ARM_SCPI_PROTOCOL || COMPILE_TEST
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 92c12b8..c19983a 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_COMMON_CLK_PALMAS) += clk-palmas.o
obj-$(CONFIG_COMMON_CLK_PWM) += clk-pwm.o
obj-$(CONFIG_CLK_QORIQ) += clk-qoriq.o
obj-$(CONFIG_COMMON_CLK_RK808) += clk-rk808.o
+obj-$(CONFIG_COMMON_CLK_HI655X) += clk-hi655x.o
obj-$(CONFIG_COMMON_CLK_S2MPS11) += clk-s2mps11.o
obj-$(CONFIG_COMMON_CLK_SCPI) += clk-scpi.o
obj-$(CONFIG_COMMON_CLK_SI5351) += clk-si5351.o
diff --git a/drivers/clk/clk-hi655x.c b/drivers/clk/clk-hi655x.c
new file mode 100644
index 0000000..b2bea32
--- /dev/null
+++ b/drivers/clk/clk-hi655x.c
@@ -0,0 +1,140 @@
+/*
+ * Clock driver for Hi655x
+ *
+ * Copyright (c) 2016, Linaro Ltd.
+ *
+ * Author: Daniel Lezcano <daniel.lezcano@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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 <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/hi655x-pmic.h>
+
+#define HI655X_CLK_BASE HI655X_BUS_ADDR(0x1c)
+#define HI655X_CLK_SET BIT(6)
+
+struct hi655x_clk {
+ struct hi655x_pmic *hi655x;
+ struct clk_hw clk_hw;
+};
+
+static unsigned long hi655x_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return 32768;
+}
+
+static int hi655x_clk_enable(struct clk_hw *hw, bool enable)
+{
+ struct hi655x_clk *hi655x_clk =
+ container_of(hw, struct hi655x_clk, clk_hw);
+
+ struct hi655x_pmic *hi655x = hi655x_clk->hi655x;
+
+ return regmap_update_bits(hi655x->regmap, HI655X_CLK_BASE,
+ HI655X_CLK_SET, enable ? HI655X_CLK_SET : 0);
+}
+
+static int hi655x_clk_prepare(struct clk_hw *hw)
+{
+ return hi655x_clk_enable(hw, true);
+}
+
+static void hi655x_clk_unprepare(struct clk_hw *hw)
+{
+ hi655x_clk_enable(hw, false);
+}
+
+static int hi655x_clk_is_prepared(struct clk_hw *hw)
+{
+ struct hi655x_clk *hi655x_clk =
+ container_of(hw, struct hi655x_clk, clk_hw);
+ struct hi655x_pmic *hi655x = hi655x_clk->hi655x;
+ int ret;
+ uint32_t val;
+
+ ret = regmap_read(hi655x->regmap, HI655X_CLK_BASE, &val);
+ if (ret < 0)
+ return ret;
+
+ return val & HI655X_CLK_BASE;
+}
+
+static const struct clk_ops hi655x_clk_ops = {
+ .prepare = hi655x_clk_prepare,
+ .unprepare = hi655x_clk_unprepare,
+ .is_prepared = hi655x_clk_is_prepared,
+ .recalc_rate = hi655x_clk_recalc_rate,
+};
+
+static int hi655x_clk_probe(struct platform_device *pdev)
+{
+ struct device *parent = pdev->dev.parent;
+ struct hi655x_pmic *hi655x = dev_get_drvdata(parent);
+ struct clk_init_data *hi655x_clk_init;
+ struct hi655x_clk *hi655x_clk;
+ const char *clk_name = "hi655x-clk";
+ int ret;
+
+ hi655x_clk = devm_kzalloc(&pdev->dev, sizeof(*hi655x_clk), GFP_KERNEL);
+ if (!hi655x_clk)
+ return -ENOMEM;
+
+ hi655x_clk_init = devm_kzalloc(&pdev->dev, sizeof(*hi655x_clk_init),
+ GFP_KERNEL);
+ if (!hi655x_clk_init)
+ return -ENOMEM;
+
+ of_property_read_string_index(parent->of_node, "clock-output-names",
+ 0, &clk_name);
+
+ hi655x_clk_init->name = clk_name;
+ hi655x_clk_init->ops = &hi655x_clk_ops;
+
+ hi655x_clk->clk_hw.init = hi655x_clk_init;
+ hi655x_clk->hi655x = hi655x;
+
+ platform_set_drvdata(pdev, hi655x_clk);
+
+ ret = devm_clk_hw_register(&pdev->dev, &hi655x_clk->clk_hw);
+ if (ret)
+ return ret;
+
+ ret = of_clk_add_hw_provider(parent->of_node, of_clk_hw_simple_get,
+ &hi655x_clk->clk_hw);
+ if (ret)
+ return ret;
+
+ ret = clk_hw_register_clkdev(&hi655x_clk->clk_hw, clk_name, NULL);
+ if (ret)
+ of_clk_del_provider(parent->of_node);
+
+ return ret;
+}
+
+static struct platform_driver hi655x_clk_driver = {
+ .probe = hi655x_clk_probe,
+ .driver = {
+ .name = "hi655x-clk",
+ },
+};
+
+module_platform_driver(hi655x_clk_driver);
+
+MODULE_DESCRIPTION("Clk driver for the hi655x series PMICs");
+MODULE_AUTHOR("Daniel Lezcano <daniel.lezcano@linaro.org>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:hi655x-clk");
diff --git a/drivers/mfd/hi655x-pmic.c b/drivers/mfd/hi655x-pmic.c
index ba706ad..c37ccbf 100644
--- a/drivers/mfd/hi655x-pmic.c
+++ b/drivers/mfd/hi655x-pmic.c
@@ -77,7 +77,8 @@
.num_resources = ARRAY_SIZE(pwrkey_resources),
.resources = &pwrkey_resources[0],
},
- { .name = "hi655x-regulator", },
+ { .name = "hi655x-regulator", },
+ { .name = "hi655x-clk", },
};

static void hi655x_local_irq_clear(struct regmap *map)
--
1.9.1