diff options
Diffstat (limited to 'drivers/clk/sunxi/clk-usb.c')
-rw-r--r-- | drivers/clk/sunxi/clk-usb.c | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/drivers/clk/sunxi/clk-usb.c b/drivers/clk/sunxi/clk-usb.c new file mode 100644 index 000000000000..f1dcc8fb5a7d --- /dev/null +++ b/drivers/clk/sunxi/clk-usb.c @@ -0,0 +1,190 @@ +/* + * Copyright 2013-2015 Emilio López + * + * Emilio López <emilio@elopez.com.ar> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/reset-controller.h> +#include <linux/spinlock.h> + + +/** + * sunxi_usb_reset... - reset bits in usb clk registers handling + */ + +struct usb_reset_data { + void __iomem *reg; + spinlock_t *lock; + struct reset_controller_dev rcdev; +}; + +static int sunxi_usb_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct usb_reset_data *data = container_of(rcdev, + struct usb_reset_data, + rcdev); + unsigned long flags; + u32 reg; + + spin_lock_irqsave(data->lock, flags); + + reg = readl(data->reg); + writel(reg & ~BIT(id), data->reg); + + spin_unlock_irqrestore(data->lock, flags); + + return 0; +} + +static int sunxi_usb_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct usb_reset_data *data = container_of(rcdev, + struct usb_reset_data, + rcdev); + unsigned long flags; + u32 reg; + + spin_lock_irqsave(data->lock, flags); + + reg = readl(data->reg); + writel(reg | BIT(id), data->reg); + + spin_unlock_irqrestore(data->lock, flags); + + return 0; +} + +static struct reset_control_ops sunxi_usb_reset_ops = { + .assert = sunxi_usb_reset_assert, + .deassert = sunxi_usb_reset_deassert, +}; + +/** + * sunxi_usb_clk_setup() - Setup function for usb gate clocks + */ + +#define SUNXI_USB_MAX_SIZE 32 + +struct usb_clk_data { + u32 clk_mask; + u32 reset_mask; +}; + +static void __init sunxi_usb_clk_setup(struct device_node *node, + const struct usb_clk_data *data, + spinlock_t *lock) +{ + struct clk_onecell_data *clk_data; + struct usb_reset_data *reset_data; + const char *clk_parent; + const char *clk_name; + void __iomem *reg; + int qty; + int i = 0; + int j = 0; + + reg = of_io_request_and_map(node, 0, of_node_full_name(node)); + if (IS_ERR(reg)) + return; + + clk_parent = of_clk_get_parent_name(node, 0); + if (!clk_parent) + return; + + /* Worst-case size approximation and memory allocation */ + qty = find_last_bit((unsigned long *)&data->clk_mask, + SUNXI_USB_MAX_SIZE); + + clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL); + if (!clk_data) + return; + + clk_data->clks = kzalloc((qty+1) * sizeof(struct clk *), GFP_KERNEL); + if (!clk_data->clks) { + kfree(clk_data); + return; + } + + for_each_set_bit(i, (unsigned long *)&data->clk_mask, + SUNXI_USB_MAX_SIZE) { + of_property_read_string_index(node, "clock-output-names", + j, &clk_name); + clk_data->clks[i] = clk_register_gate(NULL, clk_name, + clk_parent, 0, + reg, i, 0, lock); + WARN_ON(IS_ERR(clk_data->clks[i])); + + j++; + } + + /* Adjust to the real max */ + clk_data->clk_num = i; + + of_clk_add_provider(node, of_clk_src_onecell_get, clk_data); + + /* Register a reset controller for usb with reset bits */ + if (data->reset_mask == 0) + return; + + reset_data = kzalloc(sizeof(*reset_data), GFP_KERNEL); + if (!reset_data) + return; + + reset_data->reg = reg; + reset_data->lock = lock; + reset_data->rcdev.nr_resets = __fls(data->reset_mask) + 1; + reset_data->rcdev.ops = &sunxi_usb_reset_ops; + reset_data->rcdev.of_node = node; + reset_controller_register(&reset_data->rcdev); +} + +static const struct usb_clk_data sun4i_a10_usb_clk_data __initconst = { + .clk_mask = BIT(8) | BIT(7) | BIT(6), + .reset_mask = BIT(2) | BIT(1) | BIT(0), +}; + +static DEFINE_SPINLOCK(sun4i_a10_usb_lock); + +static void __init sun4i_a10_usb_setup(struct device_node *node) +{ + sunxi_usb_clk_setup(node, &sun4i_a10_usb_clk_data, &sun4i_a10_usb_lock); +} +CLK_OF_DECLARE(sun4i_a10_usb, "allwinner,sun4i-a10-usb-clk", sun4i_a10_usb_setup); + +static const struct usb_clk_data sun5i_a13_usb_clk_data __initconst = { + .clk_mask = BIT(8) | BIT(6), + .reset_mask = BIT(1) | BIT(0), +}; + +static void __init sun5i_a13_usb_setup(struct device_node *node) +{ + sunxi_usb_clk_setup(node, &sun5i_a13_usb_clk_data, &sun4i_a10_usb_lock); +} +CLK_OF_DECLARE(sun5i_a13_usb, "allwinner,sun5i-a13-usb-clk", sun5i_a13_usb_setup); + +static const struct usb_clk_data sun6i_a31_usb_clk_data __initconst = { + .clk_mask = BIT(18) | BIT(17) | BIT(16) | BIT(10) | BIT(9) | BIT(8), + .reset_mask = BIT(2) | BIT(1) | BIT(0), +}; + +static void __init sun6i_a31_usb_setup(struct device_node *node) +{ + sunxi_usb_clk_setup(node, &sun6i_a31_usb_clk_data, &sun4i_a10_usb_lock); +} +CLK_OF_DECLARE(sun6i_a31_usb, "allwinner,sun6i-a31-usb-clk", sun6i_a31_usb_setup); |