linux/drivers/clk/clk-twl6040.c
Thomas Gleixner 2b27bdcc20 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 336
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 246 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.674189849@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:07 +02:00

163 lines
3.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* TWL6040 clock module driver for OMAP4 McPDM functional clock
*
* Copyright (C) 2012 Texas Instruments Inc.
* Peter Ujfalusi <peter.ujfalusi@ti.com>
*/
#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_pdmclk {
struct twl6040 *twl6040;
struct device *dev;
struct clk_hw pdmclk_hw;
int enabled;
};
static int twl6040_pdmclk_is_prepared(struct clk_hw *hw)
{
struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk,
pdmclk_hw);
return pdmclk->enabled;
}
static int twl6040_pdmclk_reset_one_clock(struct twl6040_pdmclk *pdmclk,
unsigned int reg)
{
const u8 reset_mask = TWL6040_HPLLRST; /* Same for HPPLL and LPPLL */
int ret;
ret = twl6040_set_bits(pdmclk->twl6040, reg, reset_mask);
if (ret < 0)
return ret;
ret = twl6040_clear_bits(pdmclk->twl6040, reg, reset_mask);
if (ret < 0)
return ret;
return 0;
}
/*
* TWL6040A2 Phoenix Audio IC erratum #6: "PDM Clock Generation Issue At
* Cold Temperature". This affects cold boot and deeper idle states it
* seems. The workaround consists of resetting HPPLL and LPPLL.
*/
static int twl6040_pdmclk_quirk_reset_clocks(struct twl6040_pdmclk *pdmclk)
{
int ret;
ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_HPPLLCTL);
if (ret)
return ret;
ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_LPPLLCTL);
if (ret)
return ret;
return 0;
}
static int twl6040_pdmclk_prepare(struct clk_hw *hw)
{
struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk,
pdmclk_hw);
int ret;
ret = twl6040_power(pdmclk->twl6040, 1);
if (ret)
return ret;
ret = twl6040_pdmclk_quirk_reset_clocks(pdmclk);
if (ret)
goto out_err;
pdmclk->enabled = 1;
return 0;
out_err:
dev_err(pdmclk->dev, "%s: error %i\n", __func__, ret);
twl6040_power(pdmclk->twl6040, 0);
return ret;
}
static void twl6040_pdmclk_unprepare(struct clk_hw *hw)
{
struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk,
pdmclk_hw);
int ret;
ret = twl6040_power(pdmclk->twl6040, 0);
if (!ret)
pdmclk->enabled = 0;
}
static unsigned long twl6040_pdmclk_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk,
pdmclk_hw);
return twl6040_get_sysclk(pdmclk->twl6040);
}
static const struct clk_ops twl6040_pdmclk_ops = {
.is_prepared = twl6040_pdmclk_is_prepared,
.prepare = twl6040_pdmclk_prepare,
.unprepare = twl6040_pdmclk_unprepare,
.recalc_rate = twl6040_pdmclk_recalc_rate,
};
static const struct clk_init_data twl6040_pdmclk_init = {
.name = "pdmclk",
.ops = &twl6040_pdmclk_ops,
.flags = CLK_GET_RATE_NOCACHE,
};
static int twl6040_pdmclk_probe(struct platform_device *pdev)
{
struct twl6040 *twl6040 = dev_get_drvdata(pdev->dev.parent);
struct twl6040_pdmclk *clkdata;
int ret;
clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL);
if (!clkdata)
return -ENOMEM;
clkdata->dev = &pdev->dev;
clkdata->twl6040 = twl6040;
clkdata->pdmclk_hw.init = &twl6040_pdmclk_init;
ret = devm_clk_hw_register(&pdev->dev, &clkdata->pdmclk_hw);
if (ret)
return ret;
platform_set_drvdata(pdev, clkdata);
return devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_simple_get,
&clkdata->pdmclk_hw);
}
static struct platform_driver twl6040_pdmclk_driver = {
.driver = {
.name = "twl6040-pdmclk",
},
.probe = twl6040_pdmclk_probe,
};
module_platform_driver(twl6040_pdmclk_driver);
MODULE_DESCRIPTION("TWL6040 clock driver for McPDM functional clock");
MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
MODULE_ALIAS("platform:twl6040-pdmclk");
MODULE_LICENSE("GPL");