kernel/drivers/clk/qcom/apcs-msm8916.c
2024-07-22 17:22:30 +08:00

143 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Qualcomm APCS clock controller driver
*
* Copyright (c) 2017, Linaro Limited
* Author: Georgi Djakov <georgi.djakov@linaro.org>
*/
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include "clk-regmap.h"
#include "clk-regmap-mux-div.h"
static const u32 gpll0_a53cc_map[] = { 4, 5 };
static const struct clk_parent_data pdata[] = {
{ .fw_name = "aux", .name = "gpll0_vote", },
{ .fw_name = "pll", .name = "a53pll", },
};
/*
* We use the notifier function for switching to a temporary safe configuration
* (mux and divider), while the A53 PLL is reconfigured.
*/
static int a53cc_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, 4, 3);
return notifier_from_errno(ret);
}
static int qcom_apcs_msm8916_clk_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device *parent = dev->parent;
struct device_node *np = parent->of_node;
struct clk_regmap_mux_div *a53cc;
struct regmap *regmap;
struct clk_init_data init = { };
int ret = -ENODEV;
regmap = dev_get_regmap(parent, NULL);
if (!regmap) {
dev_err(dev, "failed to get regmap: %d\n", ret);
return ret;
}
a53cc = devm_kzalloc(dev, sizeof(*a53cc), GFP_KERNEL);
if (!a53cc)
return -ENOMEM;
/* Use an unique name by appending parent's @unit-address */
init.name = devm_kasprintf(dev, GFP_KERNEL, "a53mux%s",
strchrnul(np->full_name, '@'));
if (!init.name)
return -ENOMEM;
init.parent_data = pdata;
init.num_parents = ARRAY_SIZE(pdata);
init.ops = &clk_regmap_mux_div_ops;
init.flags = CLK_IS_CRITICAL | CLK_SET_RATE_PARENT;
a53cc->clkr.hw.init = &init;
a53cc->clkr.regmap = regmap;
a53cc->reg_offset = 0x50;
a53cc->hid_width = 5;
a53cc->hid_shift = 0;
a53cc->src_width = 3;
a53cc->src_shift = 8;
a53cc->parent_map = gpll0_a53cc_map;
a53cc->pclk = devm_clk_get(parent, NULL);
if (IS_ERR(a53cc->pclk)) {
ret = PTR_ERR(a53cc->pclk);
if (ret != -EPROBE_DEFER)
dev_err(dev, "failed to get clk: %d\n", ret);
return ret;
}
a53cc->clk_nb.notifier_call = a53cc_notifier_cb;
ret = clk_notifier_register(a53cc->pclk, &a53cc->clk_nb);
if (ret) {
dev_err(dev, "failed to register clock notifier: %d\n", ret);
return ret;
}
ret = devm_clk_register_regmap(dev, &a53cc->clkr);
if (ret) {
dev_err(dev, "failed to register regmap clock: %d\n", ret);
goto err;
}
ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
&a53cc->clkr.hw);
if (ret) {
dev_err(dev, "failed to add clock provider: %d\n", ret);
goto err;
}
platform_set_drvdata(pdev, a53cc);
return 0;
err:
clk_notifier_unregister(a53cc->pclk, &a53cc->clk_nb);
return ret;
}
static int qcom_apcs_msm8916_clk_remove(struct platform_device *pdev)
{
struct clk_regmap_mux_div *a53cc = platform_get_drvdata(pdev);
clk_notifier_unregister(a53cc->pclk, &a53cc->clk_nb);
return 0;
}
static struct platform_driver qcom_apcs_msm8916_clk_driver = {
.probe = qcom_apcs_msm8916_clk_probe,
.remove = qcom_apcs_msm8916_clk_remove,
.driver = {
.name = "qcom-apcs-msm8916-clk",
},
};
module_platform_driver(qcom_apcs_msm8916_clk_driver);
MODULE_AUTHOR("Georgi Djakov <georgi.djakov@linaro.org>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Qualcomm MSM8916 APCS clock driver");