1 // SPDX-License-Identifier: GPL-2.0
3 * Qualcomm APCS clock controller driver
5 * Copyright (c) 2017, Linaro Limited
6 * Author: Georgi Djakov <georgi.djakov@linaro.org>
10 #include <linux/clk-provider.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/platform_device.h>
15 #include <linux/regmap.h>
17 #include "clk-regmap.h"
18 #include "clk-regmap-mux-div.h"
20 static const u32 gpll0_a53cc_map[] = { 4, 5 };
22 static const struct clk_parent_data pdata[] = {
23 { .fw_name = "aux", .name = "gpll0_vote", },
24 { .fw_name = "pll", .name = "a53pll", },
28 * We use the notifier function for switching to a temporary safe configuration
29 * (mux and divider), while the A53 PLL is reconfigured.
31 static int a53cc_notifier_cb(struct notifier_block *nb, unsigned long event,
35 struct clk_regmap_mux_div *md = container_of(nb,
36 struct clk_regmap_mux_div,
38 if (event == PRE_RATE_CHANGE)
39 /* set the mux and divider to safe frequency (400mhz) */
40 ret = mux_div_set_src_div(md, 4, 3);
42 return notifier_from_errno(ret);
45 static int qcom_apcs_msm8916_clk_probe(struct platform_device *pdev)
47 struct device *dev = &pdev->dev;
48 struct device *parent = dev->parent;
49 struct device_node *np = parent->of_node;
50 struct clk_regmap_mux_div *a53cc;
51 struct regmap *regmap;
52 struct clk_init_data init = { };
55 regmap = dev_get_regmap(parent, NULL);
57 dev_err(dev, "failed to get regmap: %d\n", ret);
61 a53cc = devm_kzalloc(dev, sizeof(*a53cc), GFP_KERNEL);
65 /* Use an unique name by appending parent's @unit-address */
66 init.name = devm_kasprintf(dev, GFP_KERNEL, "a53mux%s",
67 strchrnul(np->full_name, '@'));
71 init.parent_data = pdata;
72 init.num_parents = ARRAY_SIZE(pdata);
73 init.ops = &clk_regmap_mux_div_ops;
74 init.flags = CLK_IS_CRITICAL | CLK_SET_RATE_PARENT;
76 a53cc->clkr.hw.init = &init;
77 a53cc->clkr.regmap = regmap;
78 a53cc->reg_offset = 0x50;
83 a53cc->parent_map = gpll0_a53cc_map;
85 a53cc->pclk = devm_clk_get(parent, NULL);
86 if (IS_ERR(a53cc->pclk)) {
87 ret = PTR_ERR(a53cc->pclk);
88 if (ret != -EPROBE_DEFER)
89 dev_err(dev, "failed to get clk: %d\n", ret);
93 a53cc->clk_nb.notifier_call = a53cc_notifier_cb;
94 ret = clk_notifier_register(a53cc->pclk, &a53cc->clk_nb);
96 dev_err(dev, "failed to register clock notifier: %d\n", ret);
100 ret = devm_clk_register_regmap(dev, &a53cc->clkr);
102 dev_err(dev, "failed to register regmap clock: %d\n", ret);
106 ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
109 dev_err(dev, "failed to add clock provider: %d\n", ret);
113 platform_set_drvdata(pdev, a53cc);
118 clk_notifier_unregister(a53cc->pclk, &a53cc->clk_nb);
122 static void qcom_apcs_msm8916_clk_remove(struct platform_device *pdev)
124 struct clk_regmap_mux_div *a53cc = platform_get_drvdata(pdev);
126 clk_notifier_unregister(a53cc->pclk, &a53cc->clk_nb);
129 static struct platform_driver qcom_apcs_msm8916_clk_driver = {
130 .probe = qcom_apcs_msm8916_clk_probe,
131 .remove_new = qcom_apcs_msm8916_clk_remove,
133 .name = "qcom-apcs-msm8916-clk",
136 module_platform_driver(qcom_apcs_msm8916_clk_driver);
138 MODULE_AUTHOR("Georgi Djakov <georgi.djakov@linaro.org>");
139 MODULE_LICENSE("GPL v2");
140 MODULE_DESCRIPTION("Qualcomm MSM8916 APCS clock driver");