LXR linux/drivers/clk/sunxi/clk-sun6i-apb0-gates.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2014 Free Electrons
   4 *
   5 * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
   6 *
   7 * Allwinner A31 APB0 clock gates driver
   8 */
   9
  10#include <linux/clk-provider.h>
  11#include <linux/init.h>
  12#include <linux/of.h>
  13#include <linux/of_device.h>
  14#include <linux/platform_device.h>
  15
  16#define SUN6I_APB0_GATES_MAX_SIZE       32
  17
  18struct gates_data {
  19        DECLARE_BITMAP(mask, SUN6I_APB0_GATES_MAX_SIZE);
  20};
  21
  22static const struct gates_data sun6i_a31_apb0_gates __initconst = {
  23        .mask = {0x7F},
  24};
  25
  26static const struct gates_data sun8i_a23_apb0_gates __initconst = {
  27        .mask = {0x5D},
  28};
  29
  30static const struct of_device_id sun6i_a31_apb0_gates_clk_dt_ids[] = {
  31        { .compatible = "allwinner,sun6i-a31-apb0-gates-clk", .data = &sun6i_a31_apb0_gates },
  32        { .compatible = "allwinner,sun8i-a23-apb0-gates-clk", .data = &sun8i_a23_apb0_gates },
  33        { /* sentinel */ }
  34};
  35
  36static int sun6i_a31_apb0_gates_clk_probe(struct platform_device *pdev)
  37{
  38        struct device_node *np = pdev->dev.of_node;
  39        struct clk_onecell_data *clk_data;
  40        const struct of_device_id *device;
  41        const struct gates_data *data;
  42        const char *clk_parent;
  43        const char *clk_name;
  44        struct resource *r;
  45        void __iomem *reg;
  46        int ngates;
  47        int i;
  48        int j = 0;
  49
  50        if (!np)
  51                return -ENODEV;
  52
  53        device = of_match_device(sun6i_a31_apb0_gates_clk_dt_ids, &pdev->dev);
  54        if (!device)
  55                return -ENODEV;
  56        data = device->data;
  57
  58        r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  59        reg = devm_ioremap_resource(&pdev->dev, r);
  60        if (IS_ERR(reg))
  61                return PTR_ERR(reg);
  62
  63        clk_parent = of_clk_get_parent_name(np, 0);
  64        if (!clk_parent)
  65                return -EINVAL;
  66
  67        clk_data = devm_kzalloc(&pdev->dev, sizeof(struct clk_onecell_data),
  68                                GFP_KERNEL);
  69        if (!clk_data)
  70                return -ENOMEM;
  71
  72        /* Worst-case size approximation and memory allocation */
  73        ngates = find_last_bit(data->mask, SUN6I_APB0_GATES_MAX_SIZE);
  74        clk_data->clks = devm_kcalloc(&pdev->dev, (ngates + 1),
  75                                      sizeof(struct clk *), GFP_KERNEL);
  76        if (!clk_data->clks)
  77                return -ENOMEM;
  78
  79        for_each_set_bit(i, data->mask, SUN6I_APB0_GATES_MAX_SIZE) {
  80                of_property_read_string_index(np, "clock-output-names",
  81                                              j, &clk_name);
  82
  83                clk_data->clks[i] = clk_register_gate(&pdev->dev, clk_name,
  84                                                      clk_parent, 0, reg, i,
  85                                                      0, NULL);
  86                WARN_ON(IS_ERR(clk_data->clks[i]));
  87
  88                j++;
  89        }
  90
  91        clk_data->clk_num = ngates + 1;
  92
  93        return of_clk_add_provider(np, of_clk_src_onecell_get, clk_data);
  94}
  95
  96static struct platform_driver sun6i_a31_apb0_gates_clk_driver = {
  97        .driver = {
  98                .name = "sun6i-a31-apb0-gates-clk",
  99                .of_match_table = sun6i_a31_apb0_gates_clk_dt_ids,
 100        },
 101        .probe = sun6i_a31_apb0_gates_clk_probe,
 102};
 103builtin_platform_driver(sun6i_a31_apb0_gates_clk_driver);
 104