![Krzysztof Kozlowski](/assets/img/avatar_default.png)
Although unbinding a driver requires root privileges but it still might be used theoretically in certain attacks (by triggering NULL pointer exception or memory corruption if driver does not provide proper remove callbacks or core does not handle it). Samsung clock drivers are essential for system operation so their removal is not expected. More over, the Exynos3250 ISP clock driver does not implement remove() driver callback and it is not buildable as modules. Suppress the unbind interface for Exynos3250 ISP and S3C2410 DCLK clock drivers. Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
444 lines
12 KiB
C
444 lines
12 KiB
C
/*
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* Copyright (c) 2013 Heiko Stuebner <heiko@sntech.de>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* Common Clock Framework support for s3c24xx external clock output.
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*/
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#include <linux/clkdev.h>
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#include <linux/slab.h>
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#include <linux/clk.h>
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#include <linux/clk-provider.h>
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#include <linux/platform_device.h>
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#include <linux/module.h>
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#include "clk.h"
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/* legacy access to misccr, until dt conversion is finished */
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#include <mach/hardware.h>
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#include <mach/regs-gpio.h>
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#define MUX_DCLK0 0
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#define MUX_DCLK1 1
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#define DIV_DCLK0 2
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#define DIV_DCLK1 3
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#define GATE_DCLK0 4
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#define GATE_DCLK1 5
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#define MUX_CLKOUT0 6
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#define MUX_CLKOUT1 7
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#define DCLK_MAX_CLKS (MUX_CLKOUT1 + 1)
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enum supported_socs {
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S3C2410,
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S3C2412,
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S3C2440,
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S3C2443,
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};
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struct s3c24xx_dclk_drv_data {
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const char **clkout0_parent_names;
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int clkout0_num_parents;
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const char **clkout1_parent_names;
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int clkout1_num_parents;
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const char **mux_parent_names;
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int mux_num_parents;
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};
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/*
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* Clock for output-parent selection in misccr
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*/
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struct s3c24xx_clkout {
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struct clk_hw hw;
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u32 mask;
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u8 shift;
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};
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#define to_s3c24xx_clkout(_hw) container_of(_hw, struct s3c24xx_clkout, hw)
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static u8 s3c24xx_clkout_get_parent(struct clk_hw *hw)
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{
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struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
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int num_parents = clk_hw_get_num_parents(hw);
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u32 val;
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val = readl_relaxed(S3C24XX_MISCCR) >> clkout->shift;
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val >>= clkout->shift;
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val &= clkout->mask;
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if (val >= num_parents)
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return -EINVAL;
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return val;
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}
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static int s3c24xx_clkout_set_parent(struct clk_hw *hw, u8 index)
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{
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struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
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s3c2410_modify_misccr((clkout->mask << clkout->shift),
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(index << clkout->shift));
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return 0;
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}
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static const struct clk_ops s3c24xx_clkout_ops = {
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.get_parent = s3c24xx_clkout_get_parent,
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.set_parent = s3c24xx_clkout_set_parent,
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.determine_rate = __clk_mux_determine_rate,
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};
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static struct clk *s3c24xx_register_clkout(struct device *dev, const char *name,
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const char **parent_names, u8 num_parents,
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u8 shift, u32 mask)
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{
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struct s3c24xx_clkout *clkout;
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struct clk *clk;
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struct clk_init_data init;
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/* allocate the clkout */
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clkout = kzalloc(sizeof(*clkout), GFP_KERNEL);
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if (!clkout)
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return ERR_PTR(-ENOMEM);
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init.name = name;
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init.ops = &s3c24xx_clkout_ops;
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init.flags = CLK_IS_BASIC;
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init.parent_names = parent_names;
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init.num_parents = num_parents;
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clkout->shift = shift;
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clkout->mask = mask;
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clkout->hw.init = &init;
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clk = clk_register(dev, &clkout->hw);
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return clk;
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}
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/*
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* dclk and clkout init
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*/
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struct s3c24xx_dclk {
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struct device *dev;
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void __iomem *base;
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struct clk_onecell_data clk_data;
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struct notifier_block dclk0_div_change_nb;
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struct notifier_block dclk1_div_change_nb;
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spinlock_t dclk_lock;
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unsigned long reg_save;
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};
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#define to_s3c24xx_dclk0(x) \
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container_of(x, struct s3c24xx_dclk, dclk0_div_change_nb)
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#define to_s3c24xx_dclk1(x) \
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container_of(x, struct s3c24xx_dclk, dclk1_div_change_nb)
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static const char *dclk_s3c2410_p[] = { "pclk", "uclk" };
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static const char *clkout0_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
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"gate_dclk0" };
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static const char *clkout1_s3c2410_p[] = { "mpll", "upll", "fclk", "hclk", "pclk",
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"gate_dclk1" };
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static const char *clkout0_s3c2412_p[] = { "mpll", "upll", "rtc_clkout",
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"hclk", "pclk", "gate_dclk0" };
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static const char *clkout1_s3c2412_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
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"gate_dclk1" };
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static const char *clkout0_s3c2440_p[] = { "xti", "upll", "fclk", "hclk", "pclk",
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"gate_dclk0" };
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static const char *clkout1_s3c2440_p[] = { "mpll", "upll", "rtc_clkout",
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"hclk", "pclk", "gate_dclk1" };
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static const char *dclk_s3c2443_p[] = { "pclk", "epll" };
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static const char *clkout0_s3c2443_p[] = { "xti", "epll", "armclk", "hclk", "pclk",
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"gate_dclk0" };
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static const char *clkout1_s3c2443_p[] = { "dummy", "epll", "rtc_clkout",
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"hclk", "pclk", "gate_dclk1" };
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#define DCLKCON_DCLK_DIV_MASK 0xf
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#define DCLKCON_DCLK0_DIV_SHIFT 4
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#define DCLKCON_DCLK0_CMP_SHIFT 8
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#define DCLKCON_DCLK1_DIV_SHIFT 20
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#define DCLKCON_DCLK1_CMP_SHIFT 24
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static void s3c24xx_dclk_update_cmp(struct s3c24xx_dclk *s3c24xx_dclk,
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int div_shift, int cmp_shift)
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{
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unsigned long flags = 0;
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u32 dclk_con, div, cmp;
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spin_lock_irqsave(&s3c24xx_dclk->dclk_lock, flags);
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dclk_con = readl_relaxed(s3c24xx_dclk->base);
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div = ((dclk_con >> div_shift) & DCLKCON_DCLK_DIV_MASK) + 1;
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cmp = ((div + 1) / 2) - 1;
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dclk_con &= ~(DCLKCON_DCLK_DIV_MASK << cmp_shift);
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dclk_con |= (cmp << cmp_shift);
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writel_relaxed(dclk_con, s3c24xx_dclk->base);
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spin_unlock_irqrestore(&s3c24xx_dclk->dclk_lock, flags);
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}
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static int s3c24xx_dclk0_div_notify(struct notifier_block *nb,
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unsigned long event, void *data)
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{
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struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk0(nb);
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if (event == POST_RATE_CHANGE) {
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s3c24xx_dclk_update_cmp(s3c24xx_dclk,
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DCLKCON_DCLK0_DIV_SHIFT, DCLKCON_DCLK0_CMP_SHIFT);
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}
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return NOTIFY_DONE;
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}
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static int s3c24xx_dclk1_div_notify(struct notifier_block *nb,
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unsigned long event, void *data)
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{
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struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk1(nb);
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if (event == POST_RATE_CHANGE) {
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s3c24xx_dclk_update_cmp(s3c24xx_dclk,
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DCLKCON_DCLK1_DIV_SHIFT, DCLKCON_DCLK1_CMP_SHIFT);
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}
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return NOTIFY_DONE;
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}
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#ifdef CONFIG_PM_SLEEP
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static int s3c24xx_dclk_suspend(struct device *dev)
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{
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struct platform_device *pdev = to_platform_device(dev);
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struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
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s3c24xx_dclk->reg_save = readl_relaxed(s3c24xx_dclk->base);
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return 0;
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}
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static int s3c24xx_dclk_resume(struct device *dev)
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{
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struct platform_device *pdev = to_platform_device(dev);
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struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
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writel_relaxed(s3c24xx_dclk->reg_save, s3c24xx_dclk->base);
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return 0;
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}
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#endif
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static SIMPLE_DEV_PM_OPS(s3c24xx_dclk_pm_ops,
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s3c24xx_dclk_suspend, s3c24xx_dclk_resume);
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static int s3c24xx_dclk_probe(struct platform_device *pdev)
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{
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struct s3c24xx_dclk *s3c24xx_dclk;
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struct resource *mem;
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struct clk **clk_table;
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struct s3c24xx_dclk_drv_data *dclk_variant;
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int ret, i;
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s3c24xx_dclk = devm_kzalloc(&pdev->dev, sizeof(*s3c24xx_dclk),
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GFP_KERNEL);
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if (!s3c24xx_dclk)
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return -ENOMEM;
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s3c24xx_dclk->dev = &pdev->dev;
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platform_set_drvdata(pdev, s3c24xx_dclk);
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spin_lock_init(&s3c24xx_dclk->dclk_lock);
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clk_table = devm_kzalloc(&pdev->dev,
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sizeof(struct clk *) * DCLK_MAX_CLKS,
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GFP_KERNEL);
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if (!clk_table)
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return -ENOMEM;
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s3c24xx_dclk->clk_data.clks = clk_table;
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s3c24xx_dclk->clk_data.clk_num = DCLK_MAX_CLKS;
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mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
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s3c24xx_dclk->base = devm_ioremap_resource(&pdev->dev, mem);
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if (IS_ERR(s3c24xx_dclk->base))
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return PTR_ERR(s3c24xx_dclk->base);
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dclk_variant = (struct s3c24xx_dclk_drv_data *)
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platform_get_device_id(pdev)->driver_data;
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clk_table[MUX_DCLK0] = clk_register_mux(&pdev->dev, "mux_dclk0",
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dclk_variant->mux_parent_names,
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dclk_variant->mux_num_parents, 0,
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s3c24xx_dclk->base, 1, 1, 0,
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&s3c24xx_dclk->dclk_lock);
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clk_table[MUX_DCLK1] = clk_register_mux(&pdev->dev, "mux_dclk1",
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dclk_variant->mux_parent_names,
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dclk_variant->mux_num_parents, 0,
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s3c24xx_dclk->base, 17, 1, 0,
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&s3c24xx_dclk->dclk_lock);
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clk_table[DIV_DCLK0] = clk_register_divider(&pdev->dev, "div_dclk0",
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"mux_dclk0", 0, s3c24xx_dclk->base,
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4, 4, 0, &s3c24xx_dclk->dclk_lock);
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clk_table[DIV_DCLK1] = clk_register_divider(&pdev->dev, "div_dclk1",
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"mux_dclk1", 0, s3c24xx_dclk->base,
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20, 4, 0, &s3c24xx_dclk->dclk_lock);
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clk_table[GATE_DCLK0] = clk_register_gate(&pdev->dev, "gate_dclk0",
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"div_dclk0", CLK_SET_RATE_PARENT,
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s3c24xx_dclk->base, 0, 0,
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&s3c24xx_dclk->dclk_lock);
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clk_table[GATE_DCLK1] = clk_register_gate(&pdev->dev, "gate_dclk1",
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"div_dclk1", CLK_SET_RATE_PARENT,
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s3c24xx_dclk->base, 16, 0,
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&s3c24xx_dclk->dclk_lock);
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clk_table[MUX_CLKOUT0] = s3c24xx_register_clkout(&pdev->dev,
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"clkout0", dclk_variant->clkout0_parent_names,
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dclk_variant->clkout0_num_parents, 4, 7);
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clk_table[MUX_CLKOUT1] = s3c24xx_register_clkout(&pdev->dev,
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"clkout1", dclk_variant->clkout1_parent_names,
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dclk_variant->clkout1_num_parents, 8, 7);
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for (i = 0; i < DCLK_MAX_CLKS; i++)
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if (IS_ERR(clk_table[i])) {
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dev_err(&pdev->dev, "clock %d failed to register\n", i);
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ret = PTR_ERR(clk_table[i]);
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goto err_clk_register;
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}
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ret = clk_register_clkdev(clk_table[MUX_DCLK0], "dclk0", NULL);
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if (!ret)
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ret = clk_register_clkdev(clk_table[MUX_DCLK1], "dclk1", NULL);
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if (!ret)
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ret = clk_register_clkdev(clk_table[MUX_CLKOUT0],
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"clkout0", NULL);
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if (!ret)
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ret = clk_register_clkdev(clk_table[MUX_CLKOUT1],
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"clkout1", NULL);
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if (ret) {
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dev_err(&pdev->dev, "failed to register aliases, %d\n", ret);
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goto err_clk_register;
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}
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s3c24xx_dclk->dclk0_div_change_nb.notifier_call =
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s3c24xx_dclk0_div_notify;
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s3c24xx_dclk->dclk1_div_change_nb.notifier_call =
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s3c24xx_dclk1_div_notify;
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ret = clk_notifier_register(clk_table[DIV_DCLK0],
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&s3c24xx_dclk->dclk0_div_change_nb);
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if (ret)
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goto err_clk_register;
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ret = clk_notifier_register(clk_table[DIV_DCLK1],
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&s3c24xx_dclk->dclk1_div_change_nb);
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if (ret)
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goto err_dclk_notify;
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return 0;
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err_dclk_notify:
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clk_notifier_unregister(clk_table[DIV_DCLK0],
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&s3c24xx_dclk->dclk0_div_change_nb);
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err_clk_register:
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for (i = 0; i < DCLK_MAX_CLKS; i++)
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if (clk_table[i] && !IS_ERR(clk_table[i]))
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clk_unregister(clk_table[i]);
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return ret;
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}
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static int s3c24xx_dclk_remove(struct platform_device *pdev)
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{
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struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
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struct clk **clk_table = s3c24xx_dclk->clk_data.clks;
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int i;
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clk_notifier_unregister(clk_table[DIV_DCLK1],
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&s3c24xx_dclk->dclk1_div_change_nb);
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clk_notifier_unregister(clk_table[DIV_DCLK0],
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&s3c24xx_dclk->dclk0_div_change_nb);
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for (i = 0; i < DCLK_MAX_CLKS; i++)
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clk_unregister(clk_table[i]);
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return 0;
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}
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static struct s3c24xx_dclk_drv_data dclk_variants[] = {
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[S3C2410] = {
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.clkout0_parent_names = clkout0_s3c2410_p,
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.clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2410_p),
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.clkout1_parent_names = clkout1_s3c2410_p,
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.clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2410_p),
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.mux_parent_names = dclk_s3c2410_p,
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.mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
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},
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[S3C2412] = {
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.clkout0_parent_names = clkout0_s3c2412_p,
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.clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2412_p),
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.clkout1_parent_names = clkout1_s3c2412_p,
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.clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2412_p),
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.mux_parent_names = dclk_s3c2410_p,
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.mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
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},
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[S3C2440] = {
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.clkout0_parent_names = clkout0_s3c2440_p,
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.clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2440_p),
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.clkout1_parent_names = clkout1_s3c2440_p,
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.clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2440_p),
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.mux_parent_names = dclk_s3c2410_p,
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.mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
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},
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[S3C2443] = {
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.clkout0_parent_names = clkout0_s3c2443_p,
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.clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2443_p),
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.clkout1_parent_names = clkout1_s3c2443_p,
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.clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2443_p),
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.mux_parent_names = dclk_s3c2443_p,
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.mux_num_parents = ARRAY_SIZE(dclk_s3c2443_p),
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},
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};
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static const struct platform_device_id s3c24xx_dclk_driver_ids[] = {
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{
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.name = "s3c2410-dclk",
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.driver_data = (kernel_ulong_t)&dclk_variants[S3C2410],
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}, {
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.name = "s3c2412-dclk",
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.driver_data = (kernel_ulong_t)&dclk_variants[S3C2412],
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}, {
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.name = "s3c2440-dclk",
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.driver_data = (kernel_ulong_t)&dclk_variants[S3C2440],
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}, {
|
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.name = "s3c2443-dclk",
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.driver_data = (kernel_ulong_t)&dclk_variants[S3C2443],
|
|
},
|
|
{ }
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(platform, s3c24xx_dclk_driver_ids);
|
|
|
|
static struct platform_driver s3c24xx_dclk_driver = {
|
|
.driver = {
|
|
.name = "s3c24xx-dclk",
|
|
.pm = &s3c24xx_dclk_pm_ops,
|
|
.suppress_bind_attrs = true,
|
|
},
|
|
.probe = s3c24xx_dclk_probe,
|
|
.remove = s3c24xx_dclk_remove,
|
|
.id_table = s3c24xx_dclk_driver_ids,
|
|
};
|
|
module_platform_driver(s3c24xx_dclk_driver);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
|
|
MODULE_DESCRIPTION("Driver for the S3C24XX external clock outputs");
|