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Commit f9f8c043 authored by Peter Ujfalusi's avatar Peter Ujfalusi Committed by Mike Turquette
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CLK: clk-twl6040: Initial clock driver for OMAP4+ McPDM fclk clock 



On OMAP4+ platforms the functional clock for the McPDM IP is suplied by
the twl6040 codec (bit clock on the PDM bus).
This common clock driver for twl6040 will register the mcpdm_fclk clock to
be used by the McPDM driver to make sure that the needed clocks are
available when needed.

Signed-off-by: default avatarPeter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: default avatarMike Turquette <mturquette@linaro.org>
parent 2968f851

drivers/clk/Kconfig

+8 −0
Original line number Diff line number Diff line
@@ -53,4 +53,12 @@ config COMMON_CLK_MAX77686 
	---help---

	  This driver supports Maxim 77686 crystal oscillator clock. 



config CLK_TWL6040

	tristate "External McPDM functional clock from twl6040"

	depends on TWL6040_CORE

	---help---

	  Enable the external functional clock support on OMAP4+ platforms for

	  McPDM. McPDM module is using the external bit clock on the McPDM bus

	  as functional clock.



endmenu

drivers/clk/Makefile

+1 −0
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@@ -23,3 +23,4 @@ obj-$(CONFIG_ARCH_VT8500) += clk-vt8500.o 
# Chip specific

obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.o

obj-$(CONFIG_COMMON_CLK_MAX77686) += clk-max77686.o

obj-$(CONFIG_CLK_TWL6040)	+= clk-twl6040.o

drivers/clk/clk-twl6040.c

0 → 100644
+126 −0
Original line number Diff line number Diff line 
/*

* TWL6040 clock module driver for OMAP4 McPDM functional clock

*

* Copyright (C) 2012 Texas Instruments Inc.

* Peter Ujfalusi <peter.ujfalusi@ti.com>

*

* This program is free software; you can redistribute it and/or

* modify it under the terms of the GNU General Public License

* version 2 as published by the Free Software Foundation.

*

* 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.

*

* You should have received a copy of the GNU General Public License

* along with this program; if not, write to the Free Software

* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA

* 02110-1301 USA

*

*/



#include <linux/clk.h>

#include <linux/module.h>

#include <linux/slab.h>

#include <linux/platform_device.h>

#include <linux/mfd/twl6040.h>

#include <linux/clk-provider.h>



struct twl6040_clk {

	struct twl6040 *twl6040;

	struct device *dev;

	struct clk_hw mcpdm_fclk;

	struct clk *clk;

	int enabled;

};



static int twl6040_bitclk_is_enabled(struct clk_hw *hw)

{

	struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk,

						       mcpdm_fclk);

	return twl6040_clk->enabled;

}



static int twl6040_bitclk_prepare(struct clk_hw *hw)

{

	struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk,

						       mcpdm_fclk);

	int ret;



	ret = twl6040_power(twl6040_clk->twl6040, 1);

	if (!ret)

		twl6040_clk->enabled = 1;



	return ret;

}



static void twl6040_bitclk_unprepare(struct clk_hw *hw)

{

	struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk,

						       mcpdm_fclk);

	int ret;



	ret = twl6040_power(twl6040_clk->twl6040, 0);

	if (!ret)

		twl6040_clk->enabled = 0;

}



static const struct clk_ops twl6040_mcpdm_ops = {

	.is_enabled = twl6040_bitclk_is_enabled,

	.prepare = twl6040_bitclk_prepare,

	.unprepare = twl6040_bitclk_unprepare,

};



static struct clk_init_data wm831x_clkout_init = {

	.name = "mcpdm_fclk",

	.ops = &twl6040_mcpdm_ops,

	.flags = CLK_IS_ROOT,

};



static int __devinit twl6040_clk_probe(struct platform_device *pdev)

{

	struct twl6040 *twl6040 = dev_get_drvdata(pdev->dev.parent);

	struct twl6040_clk *clkdata;



	clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL);

	if (!clkdata)

		return -ENOMEM;



	clkdata->dev = &pdev->dev;

	clkdata->twl6040 = twl6040;



	clkdata->mcpdm_fclk.init = &wm831x_clkout_init;

	clkdata->clk = clk_register(&pdev->dev, &clkdata->mcpdm_fclk);

	if (!clkdata->clk)

		return -EINVAL;



	dev_set_drvdata(&pdev->dev, clkdata);



	return 0;

}



static int __devexit twl6040_clk_remove(struct platform_device *pdev)

{

	struct twl6040_clk *clkdata = dev_get_drvdata(&pdev->dev);



	clk_unregister(clkdata->clk);



	return 0;

}



static struct platform_driver twl6040_clk_driver = {

	.driver = {

		.name = "twl6040-clk",

		.owner = THIS_MODULE,

	},

	.probe = twl6040_clk_probe,

	.remove = __devexit_p(twl6040_clk_remove),

};



module_platform_driver(twl6040_clk_driver);



MODULE_DESCRIPTION("TWL6040 clock driver for McPDM functional clock");

MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");

MODULE_ALIAS("platform:twl6040-clk");

MODULE_LICENSE("GPL");