diff options
Diffstat (limited to 'drivers/clk/mvebu/armada-37xx-xtal.c')
| -rw-r--r-- | drivers/clk/mvebu/armada-37xx-xtal.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/drivers/clk/mvebu/armada-37xx-xtal.c b/drivers/clk/mvebu/armada-37xx-xtal.c new file mode 100644 index 000000000..537051495 --- /dev/null +++ b/drivers/clk/mvebu/armada-37xx-xtal.c @@ -0,0 +1,91 @@ +/* + * Marvell Armada 37xx SoC xtal clocks + * + * Copyright (C) 2016 Marvell + * + * Gregory CLEMENT <gregory.clement@free-electrons.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/clk-provider.h> +#include <linux/mfd/syscon.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +#define NB_GPIO1_LATCH 0x8 +#define XTAL_MODE BIT(9) + +static int armada_3700_xtal_clock_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + const char *xtal_name = "xtal"; + struct device_node *parent; + struct regmap *regmap; + struct clk_hw *xtal_hw; + unsigned int rate; + u32 reg; + int ret; + + xtal_hw = devm_kzalloc(&pdev->dev, sizeof(*xtal_hw), GFP_KERNEL); + if (!xtal_hw) + return -ENOMEM; + + platform_set_drvdata(pdev, xtal_hw); + + parent = np->parent; + if (!parent) { + dev_err(&pdev->dev, "no parent\n"); + return -ENODEV; + } + + regmap = syscon_node_to_regmap(parent); + if (IS_ERR(regmap)) { + dev_err(&pdev->dev, "cannot get regmap\n"); + return PTR_ERR(regmap); + } + + ret = regmap_read(regmap, NB_GPIO1_LATCH, ®); + if (ret) { + dev_err(&pdev->dev, "cannot read from regmap\n"); + return ret; + } + + if (reg & XTAL_MODE) + rate = 40000000; + else + rate = 25000000; + + of_property_read_string_index(np, "clock-output-names", 0, &xtal_name); + xtal_hw = clk_hw_register_fixed_rate(NULL, xtal_name, NULL, 0, rate); + if (IS_ERR(xtal_hw)) + return PTR_ERR(xtal_hw); + ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, xtal_hw); + + return ret; +} + +static int armada_3700_xtal_clock_remove(struct platform_device *pdev) +{ + of_clk_del_provider(pdev->dev.of_node); + + return 0; +} + +static const struct of_device_id armada_3700_xtal_clock_of_match[] = { + { .compatible = "marvell,armada-3700-xtal-clock", }, + { } +}; + +static struct platform_driver armada_3700_xtal_clock_driver = { + .probe = armada_3700_xtal_clock_probe, + .remove = armada_3700_xtal_clock_remove, + .driver = { + .name = "marvell-armada-3700-xtal-clock", + .of_match_table = armada_3700_xtal_clock_of_match, + }, +}; + +builtin_platform_driver(armada_3700_xtal_clock_driver); |