Device ams AS3722 supports one clock 32KHz output. Add clock driver to control the clock through clock framework. Signed-off-by: Laxman Dewangan <ldewangan@xxxxxxxxxx> --- Changes from V1: - None. drivers/clk/Kconfig | 8 ++ drivers/clk/Makefile | 1 + drivers/clk/clk-as3722.c | 161 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 170 insertions(+), 0 deletions(-) create mode 100644 drivers/clk/clk-as3722.c diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 5c51115..03257bf 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -78,6 +78,14 @@ config CLK_TWL6040 McPDM. McPDM module is using the external bit clock on the McPDM bus as functional clock. +config COMMON_CLK_AS3722 + tristate "ams AS3722 clock32K driver" + depends on MFD_AS3722 + help + ---help--- + Supports the clocking subsystem of the ams AS3722 PMIC from ams. + This device supports one 32KHz clock. + config COMMON_CLK_AXI_CLKGEN tristate "AXI clkgen driver" depends on ARCH_ZYNQ || MICROBLAZE diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index fe3121b..b94624d 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -39,6 +39,7 @@ obj-$(CONFIG_COMMON_CLK_KEYSTONE) += keystone/ obj-$(CONFIG_X86) += x86/ # Chip specific +obj-$(CONFIG_COMMON_CLK_AS3722) += clk-as3722.o obj-$(CONFIG_COMMON_CLK_AXI_CLKGEN) += clk-axi-clkgen.o obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.o obj-$(CONFIG_COMMON_CLK_MAX77686) += clk-max77686.o diff --git a/drivers/clk/clk-as3722.c b/drivers/clk/clk-as3722.c new file mode 100644 index 0000000..0f786c3 --- /dev/null +++ b/drivers/clk/clk-as3722.c @@ -0,0 +1,161 @@ +/* + * Clock driver for ams AS3722 device. + * + * Copyright (c) 2013, NVIDIA Corporation. + * + * Author: Laxman Dewangan <ldewangan@xxxxxxxxxx> + * + * 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 version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind, + * whether express or implied; 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.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/mfd/as3722.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +struct as3722_clks { + struct device *dev; + struct as3722 *as3722; + struct clk_hw hw; + struct clk *clk; + struct clk_onecell_data clk_data; +}; + +static inline struct as3722_clks *to_as3722_clks(struct clk_hw *hw) +{ + return container_of(hw, struct as3722_clks, hw); +} + +static unsigned long as3722_clks_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + return 32768; +} + +static int as3722_clks_prepare(struct clk_hw *hw) +{ + struct as3722_clks *as3722_clks = to_as3722_clks(hw); + int ret; + + ret = as3722_update_bits(as3722_clks->as3722, AS3722_RTC_CONTROL_REG, + AS3722_RTC_CLK32K_OUT_EN, AS3722_RTC_CLK32K_OUT_EN); + if (ret < 0) + dev_err(as3722_clks->dev, "RTC_CONTROL_REG update failed, %d\n", + ret); + + return ret; +} + +static void as3722_clks_unprepare(struct clk_hw *hw) +{ + struct as3722_clks *as3722_clks = to_as3722_clks(hw); + int ret; + + ret = as3722_update_bits(as3722_clks->as3722, AS3722_RTC_CONTROL_REG, + AS3722_RTC_CLK32K_OUT_EN, 0); + if (ret < 0) + dev_err(as3722_clks->dev, "RTC_CONTROL_REG update failed, %d\n", + ret); +} + +static int as3722_clks_is_prepared(struct clk_hw *hw) +{ + struct as3722_clks *as3722_clks = to_as3722_clks(hw); + int ret; + u32 val; + + ret = as3722_read(as3722_clks->as3722, AS3722_RTC_CONTROL_REG, &val); + if (ret < 0) { + dev_err(as3722_clks->dev, "RTC_CONTROL_REG read failed, %d\n", + ret); + return ret; + } + + return !!(val & AS3722_RTC_CLK32K_OUT_EN); +} + +static struct clk_ops as3722_clks_ops = { + .prepare = as3722_clks_prepare, + .unprepare = as3722_clks_unprepare, + .is_prepared = as3722_clks_is_prepared, + .recalc_rate = as3722_clks_recalc_rate, +}; + +static struct clk_init_data as3722_clks_hw_init = { + .name = "clk32k", + .ops = &as3722_clks_ops, + .flags = CLK_IS_ROOT | CLK_IGNORE_UNUSED, +}; + +static int as3722_clks_probe(struct platform_device *pdev) +{ + struct as3722_clks *as3722_clks; + struct clk *clk; + int ret; + + as3722_clks = devm_kzalloc(&pdev->dev, sizeof(*as3722_clks), + GFP_KERNEL); + if (!as3722_clks) + return -ENOMEM; + + as3722_clks->clk_data.clks = devm_kzalloc(&pdev->dev, + sizeof(*as3722_clks->clk_data.clks), GFP_KERNEL); + if (!as3722_clks->clk_data.clks) + return -ENOMEM; + + platform_set_drvdata(pdev, as3722_clks); + + as3722_clks->as3722 = dev_get_drvdata(pdev->dev.parent); + as3722_clks->dev = &pdev->dev; + as3722_clks->hw.init = &as3722_clks_hw_init; + + clk = devm_clk_register(&pdev->dev, &as3722_clks->hw); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + dev_err(&pdev->dev, "Fail to register clock %s, %d\n", + as3722_clks_hw_init.name, ret); + return ret; + } + as3722_clks->clk = clk; + as3722_clks->clk_data.clks[0] = clk; + as3722_clks->clk_data.clk_num = 1; + ret = of_clk_add_provider(pdev->dev.parent->of_node, + of_clk_src_simple_get, &as3722_clks->clk_data); + if (ret < 0) + dev_err(&pdev->dev, "Fail to add clock driver, %d\n", ret); + return ret; +} + +static int as3722_clks_remove(struct platform_device *pdev) +{ + of_clk_del_provider(pdev->dev.parent->of_node); + return 0; +} + +static struct platform_driver as3722_clks_driver = { + .driver = { + .name = "as3722-clk", + .owner = THIS_MODULE, + }, + .probe = as3722_clks_probe, + .remove = as3722_clks_remove, +}; + +module_platform_driver(as3722_clks_driver); + +MODULE_DESCRIPTION("Clock driver for ams AS3722 PMIC Device"); +MODULE_ALIAS("platform:as3722-clk"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@xxxxxxxxxx>"); +MODULE_LICENSE("GPL v2"); -- 1.7.1.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html