diff options
Diffstat (limited to 'drivers/clk/qcom/apcs-sdx55.c')
| -rw-r--r-- | drivers/clk/qcom/apcs-sdx55.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/drivers/clk/qcom/apcs-sdx55.c b/drivers/clk/qcom/apcs-sdx55.c new file mode 100644 index 000000000..e599f862e --- /dev/null +++ b/drivers/clk/qcom/apcs-sdx55.c @@ -0,0 +1,145 @@ +// 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(dev, "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)) + return dev_err_probe(dev, PTR_ERR(a7cc->pclk), + "Failed to get PLL clk\n"); + + a7cc->clk_nb.notifier_call = a7cc_notifier_cb; + ret = clk_notifier_register(a7cc->pclk, &a7cc->clk_nb); + if (ret) + return dev_err_probe(dev, ret, + "Failed to register clock notifier\n"); + + 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"); |