Staging
v0.5.2
v0.5.2
https://github.com/torvalds/linux
Tip revision: 6efb943b8616ec53a5e444193dccf1af9ad627b5 authored by Linus Torvalds on 09 May 2021, 21:17:44 UTC
Linux 5.13-rc1
Linux 5.13-rc1
Tip revision: 6efb943
apcs-sdx55.c
// SPDX-License-Identifier: GPL-2.0
/*
* Qualcomm SDX55 APCS clock controller driver
*
* Copyright (c) 2020, Linaro Limited
* Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
*/
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/cpu.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include "clk-regmap.h"
#include "clk-regmap-mux-div.h"
static const u32 apcs_mux_clk_parent_map[] = { 0, 1, 5 };
static const struct clk_parent_data pdata[] = {
{ .fw_name = "ref" },
{ .fw_name = "aux" },
{ .fw_name = "pll" },
};
/*
* We use the notifier function for switching to a temporary safe configuration
* (mux and divider), while the A7 PLL is reconfigured.
*/
static int a7cc_notifier_cb(struct notifier_block *nb, unsigned long event,
void *data)
{
int ret = 0;
struct clk_regmap_mux_div *md = container_of(nb,
struct clk_regmap_mux_div,
clk_nb);
if (event == PRE_RATE_CHANGE)
/* set the mux and divider to safe frequency (400mhz) */
ret = mux_div_set_src_div(md, 1, 2);
return notifier_from_errno(ret);
}
static int qcom_apcs_sdx55_clk_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device *parent = dev->parent;
struct device *cpu_dev;
struct clk_regmap_mux_div *a7cc;
struct regmap *regmap;
struct clk_init_data init = { };
int ret;
regmap = dev_get_regmap(parent, NULL);
if (!regmap) {
dev_err_probe(dev, -ENODEV, "Failed to get parent regmap\n");
return -ENODEV;
}
a7cc = devm_kzalloc(dev, sizeof(*a7cc), GFP_KERNEL);
if (!a7cc)
return -ENOMEM;
init.name = "a7mux";
init.parent_data = pdata;
init.num_parents = ARRAY_SIZE(pdata);
init.ops = &clk_regmap_mux_div_ops;
a7cc->clkr.hw.init = &init;
a7cc->clkr.regmap = regmap;
a7cc->reg_offset = 0x8;
a7cc->hid_width = 5;
a7cc->hid_shift = 0;
a7cc->src_width = 3;
a7cc->src_shift = 8;
a7cc->parent_map = apcs_mux_clk_parent_map;
a7cc->pclk = devm_clk_get(parent, "pll");
if (IS_ERR(a7cc->pclk)) {
ret = PTR_ERR(a7cc->pclk);
if (ret != -EPROBE_DEFER)
dev_err_probe(dev, ret, "Failed to get PLL clk\n");
return ret;
}
a7cc->clk_nb.notifier_call = a7cc_notifier_cb;
ret = clk_notifier_register(a7cc->pclk, &a7cc->clk_nb);
if (ret) {
dev_err_probe(dev, ret, "Failed to register clock notifier\n");
return ret;
}
ret = devm_clk_register_regmap(dev, &a7cc->clkr);
if (ret) {
dev_err_probe(dev, ret, "Failed to register regmap clock\n");
goto err;
}
ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
&a7cc->clkr.hw);
if (ret) {
dev_err_probe(dev, ret, "Failed to add clock provider\n");
goto err;
}
platform_set_drvdata(pdev, a7cc);
/*
* Attach the power domain to cpudev. Since there is no dedicated driver
* for CPUs and the SDX55 platform lacks hardware specific CPUFreq
* driver, there seems to be no better place to do this. So do it here!
*/
cpu_dev = get_cpu_device(0);
dev_pm_domain_attach(cpu_dev, true);
return 0;
err:
clk_notifier_unregister(a7cc->pclk, &a7cc->clk_nb);
return ret;
}
static int qcom_apcs_sdx55_clk_remove(struct platform_device *pdev)
{
struct device *cpu_dev = get_cpu_device(0);
struct clk_regmap_mux_div *a7cc = platform_get_drvdata(pdev);
clk_notifier_unregister(a7cc->pclk, &a7cc->clk_nb);
dev_pm_domain_detach(cpu_dev, true);
return 0;
}
static struct platform_driver qcom_apcs_sdx55_clk_driver = {
.probe = qcom_apcs_sdx55_clk_probe,
.remove = qcom_apcs_sdx55_clk_remove,
.driver = {
.name = "qcom-sdx55-acps-clk",
},
};
module_platform_driver(qcom_apcs_sdx55_clk_driver);
MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Qualcomm SDX55 APCS clock driver");