diff options
Diffstat (limited to 'kernel/drivers/clk/sunxi/clk-sun6i-apb0-gates.c')
-rw-r--r-- | kernel/drivers/clk/sunxi/clk-sun6i-apb0-gates.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/kernel/drivers/clk/sunxi/clk-sun6i-apb0-gates.c b/kernel/drivers/clk/sunxi/clk-sun6i-apb0-gates.c new file mode 100644 index 000000000..64f3e46d3 --- /dev/null +++ b/kernel/drivers/clk/sunxi/clk-sun6i-apb0-gates.c @@ -0,0 +1,110 @@ +/* + * Copyright (C) 2014 Free Electrons + * + * License Terms: GNU General Public License v2 + * Author: Boris BREZILLON <boris.brezillon@free-electrons.com> + * + * Allwinner A31 APB0 clock gates driver + * + */ + +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> + +#define SUN6I_APB0_GATES_MAX_SIZE 32 + +struct gates_data { + DECLARE_BITMAP(mask, SUN6I_APB0_GATES_MAX_SIZE); +}; + +static const struct gates_data sun6i_a31_apb0_gates __initconst = { + .mask = {0x7F}, +}; + +static const struct gates_data sun8i_a23_apb0_gates __initconst = { + .mask = {0x5D}, +}; + +static const struct of_device_id sun6i_a31_apb0_gates_clk_dt_ids[] = { + { .compatible = "allwinner,sun6i-a31-apb0-gates-clk", .data = &sun6i_a31_apb0_gates }, + { .compatible = "allwinner,sun8i-a23-apb0-gates-clk", .data = &sun8i_a23_apb0_gates }, + { /* sentinel */ } +}; + +static int sun6i_a31_apb0_gates_clk_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct clk_onecell_data *clk_data; + const struct of_device_id *device; + const struct gates_data *data; + const char *clk_parent; + const char *clk_name; + struct resource *r; + void __iomem *reg; + int ngates; + int i; + int j = 0; + + if (!np) + return -ENODEV; + + device = of_match_device(sun6i_a31_apb0_gates_clk_dt_ids, &pdev->dev); + if (!device) + return -ENODEV; + data = device->data; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + reg = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(reg)) + return PTR_ERR(reg); + + clk_parent = of_clk_get_parent_name(np, 0); + if (!clk_parent) + return -EINVAL; + + clk_data = devm_kzalloc(&pdev->dev, sizeof(struct clk_onecell_data), + GFP_KERNEL); + if (!clk_data) + return -ENOMEM; + + /* Worst-case size approximation and memory allocation */ + ngates = find_last_bit(data->mask, SUN6I_APB0_GATES_MAX_SIZE); + clk_data->clks = devm_kcalloc(&pdev->dev, (ngates + 1), + sizeof(struct clk *), GFP_KERNEL); + if (!clk_data->clks) + return -ENOMEM; + + for_each_set_bit(i, data->mask, SUN6I_APB0_GATES_MAX_SIZE) { + of_property_read_string_index(np, "clock-output-names", + j, &clk_name); + + clk_data->clks[i] = clk_register_gate(&pdev->dev, clk_name, + clk_parent, 0, reg, i, + 0, NULL); + WARN_ON(IS_ERR(clk_data->clks[i])); + clk_register_clkdev(clk_data->clks[i], clk_name, NULL); + + j++; + } + + clk_data->clk_num = ngates + 1; + + return of_clk_add_provider(np, of_clk_src_onecell_get, clk_data); +} + +static struct platform_driver sun6i_a31_apb0_gates_clk_driver = { + .driver = { + .name = "sun6i-a31-apb0-gates-clk", + .of_match_table = sun6i_a31_apb0_gates_clk_dt_ids, + }, + .probe = sun6i_a31_apb0_gates_clk_probe, +}; +module_platform_driver(sun6i_a31_apb0_gates_clk_driver); + +MODULE_AUTHOR("Boris BREZILLON <boris.brezillon@free-electrons.com>"); +MODULE_DESCRIPTION("Allwinner A31 APB0 gate clocks driver"); +MODULE_LICENSE("GPL v2"); |