From c8a76cac19eebf65f629e3676e57743f9dfeea8f Mon Sep 17 00:00:00 2001 From: Boris BREZILLON Date: Thu, 15 May 2014 10:55:11 +0200 Subject: clk: sunxi: add PRCM (Power/Reset/Clock Management) clks support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The PRCM (Power/Reset/Clock Management) unit provides several clock devices: - AR100 clk: used to clock the Power Management co-processor - AHB0 clk: used to clock the AHB0 bus - APB0 clk and gates: used to clk peripherals connected to the APB0 bus Add support for these clks in a separate driver so that they can be probed as platform devices instead of registered during early init. This is needed to be able to probe PRCM MFD subdevices. Signed-off-by: Boris BREZILLON Acked-by: Maxime Ripard Signed-off-by: Emilio López --- drivers/clk/sunxi/clk-sun6i-apb0-gates.c | 99 ++++++++++++++++++++++++++++++++ 1 file changed, 99 insertions(+) create mode 100644 drivers/clk/sunxi/clk-sun6i-apb0-gates.c (limited to 'drivers/clk/sunxi/clk-sun6i-apb0-gates.c') diff --git a/drivers/clk/sunxi/clk-sun6i-apb0-gates.c b/drivers/clk/sunxi/clk-sun6i-apb0-gates.c new file mode 100644 index 000000000000..44cd27c5c401 --- /dev/null +++ b/drivers/clk/sunxi/clk-sun6i-apb0-gates.c @@ -0,0 +1,99 @@ +/* + * Copyright (C) 2014 Free Electrons + * + * License Terms: GNU General Public License v2 + * Author: Boris BREZILLON + * + * Allwinner A31 APB0 clock gates driver + * + */ + +#include +#include +#include +#include + +#define SUN6I_APB0_GATES_MAX_SIZE 32 + +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 char *clk_parent; + const char *clk_name; + struct resource *r; + void __iomem *reg; + int gate_id; + int ngates; + int i; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + reg = devm_ioremap_resource(&pdev->dev, r); + if (!reg) + return PTR_ERR(reg); + + clk_parent = of_clk_get_parent_name(np, 0); + if (!clk_parent) + return -EINVAL; + + ngates = of_property_count_strings(np, "clock-output-names"); + if (ngates < 0) + return ngates; + + if (!ngates || ngates > SUN6I_APB0_GATES_MAX_SIZE) + return -EINVAL; + + clk_data = devm_kzalloc(&pdev->dev, sizeof(struct clk_onecell_data), + GFP_KERNEL); + if (!clk_data) + return -ENOMEM; + + clk_data->clks = devm_kzalloc(&pdev->dev, + SUN6I_APB0_GATES_MAX_SIZE * + sizeof(struct clk *), + GFP_KERNEL); + if (!clk_data->clks) + return -ENOMEM; + + for (i = 0; i < ngates; i++) { + of_property_read_string_index(np, "clock-output-names", + i, &clk_name); + + gate_id = i; + of_property_read_u32_index(np, "clock-indices", i, &gate_id); + + WARN_ON(gate_id >= SUN6I_APB0_GATES_MAX_SIZE); + if (gate_id >= SUN6I_APB0_GATES_MAX_SIZE) + continue; + + clk_data->clks[gate_id] = clk_register_gate(&pdev->dev, + clk_name, + clk_parent, 0, + reg, gate_id, + 0, NULL); + WARN_ON(IS_ERR(clk_data->clks[gate_id])); + } + + clk_data->clk_num = ngates; + + return of_clk_add_provider(np, of_clk_src_onecell_get, clk_data); +} + +const struct of_device_id sun6i_a31_apb0_gates_clk_dt_ids[] = { + { .compatible = "allwinner,sun6i-a31-apb0-gates-clk" }, + { /* sentinel */ } +}; + +static struct platform_driver sun6i_a31_apb0_gates_clk_driver = { + .driver = { + .name = "sun6i-a31-apb0-gates-clk", + .owner = THIS_MODULE, + .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 "); +MODULE_DESCRIPTION("Allwinner A31 APB0 gate clocks driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3