linux/arch/arm/plat-samsung/clock.c

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/* linux/arch/arm/plat-s3c24xx/clock.c
*
* Copyright 2004-2005 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
*
* S3C24XX Core clock control support
*
* Based on, and code from linux/arch/arm/mach-versatile/clock.c
**
** Copyright (C) 2004 ARM Limited.
** Written by Deep Blue Solutions Limited.
*
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/clk.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#if defined(CONFIG_DEBUG_FS)
#include <linux/debugfs.h>
#endif
#include <mach/hardware.h>
#include <asm/irq.h>
#include <plat/cpu-freq.h>
#include <plat/clock.h>
#include <plat/cpu.h>
#include <linux/serial_core.h>
#include <plat/regs-serial.h> /* for s3c24xx_uart_devs */
/* clock information */
static LIST_HEAD(clocks);
/* We originally used an mutex here, but some contexts (see resume)
* are calling functions such as clk_set_parent() with IRQs disabled
* causing an BUG to be triggered.
*/
DEFINE_SPINLOCK(clocks_lock);
/* Global watchdog clock used by arch_wtd_reset() callback */
struct clk *s3c2410_wdtclk;
static int __init s3c_wdt_reset_init(void)
{
s3c2410_wdtclk = clk_get(NULL, "watchdog");
if (IS_ERR(s3c2410_wdtclk))
printk(KERN_WARNING "%s: warning: cannot get watchdog clock\n", __func__);
return 0;
}
arch_initcall(s3c_wdt_reset_init);
/* enable and disable calls for use with the clk struct */
static int clk_null_enable(struct clk *clk, int enable)
{
return 0;
}
int clk_enable(struct clk *clk)
{
unsigned long flags;
if (IS_ERR(clk) || clk == NULL)
return -EINVAL;
clk_enable(clk->parent);
spin_lock_irqsave(&clocks_lock, flags);
if ((clk->usage++) == 0)
(clk->enable)(clk, 1);
spin_unlock_irqrestore(&clocks_lock, flags);
return 0;
}
void clk_disable(struct clk *clk)
{
unsigned long flags;
if (IS_ERR(clk) || clk == NULL)
return;
spin_lock_irqsave(&clocks_lock, flags);
if ((--clk->usage) == 0)
(clk->enable)(clk, 0);
spin_unlock_irqrestore(&clocks_lock, flags);
clk_disable(clk->parent);
}
unsigned long clk_get_rate(struct clk *clk)
{
if (IS_ERR_OR_NULL(clk))
return 0;
if (clk->rate != 0)
return clk->rate;
if (clk->ops != NULL && clk->ops->get_rate != NULL)
return (clk->ops->get_rate)(clk);
if (clk->parent != NULL)
return clk_get_rate(clk->parent);
return clk->rate;
}
long clk_round_rate(struct clk *clk, unsigned long rate)
{
if (!IS_ERR_OR_NULL(clk) && clk->ops && clk->ops->round_rate)
return (clk->ops->round_rate)(clk, rate);
return rate;
}
int clk_set_rate(struct clk *clk, unsigned long rate)
{
unsigned long flags;
int ret;
if (IS_ERR_OR_NULL(clk))
return -EINVAL;
/* We do not default just do a clk->rate = rate as
* the clock may have been made this way by choice.
*/
WARN_ON(clk->ops == NULL);
WARN_ON(clk->ops && clk->ops->set_rate == NULL);
if (clk->ops == NULL || clk->ops->set_rate == NULL)
return -EINVAL;
spin_lock_irqsave(&clocks_lock, flags);
ret = (clk->ops->set_rate)(clk, rate);
spin_unlock_irqrestore(&clocks_lock, flags);
return ret;
}
struct clk *clk_get_parent(struct clk *clk)
{
return clk->parent;
}
int clk_set_parent(struct clk *clk, struct clk *parent)
{
ARM: SAMSUNG: use spin_lock_irqsave() in clk_set_parent From 0cdf3aff, "ARM: SAMSUNG: use spin_lock_irqsave() in clk_{enable,disable}": The clk_enable()and clk_disable() can be used process and ISR either. And actually it is used for real product and other platforms use it now. So spin_lock_irqsave() should be used instead. We need to make a similar change in clk_set_parent(). Otherwise, you can potentially get spinlock recursion: BUG: spinlock recursion on CPU#0, kinteractive/68 lock: 807832a8, .magic: dead4ead, .owner: kinteractive/68, .owner_cpu: 0 [<80015f54>] (unwind_backtrace+0x0/0x128) from [<804f2914>] (dump_stack+0x20/0x24) [<804f2914>] (dump_stack+0x20/0x24) from [<804f57b8>] (spin_dump+0x80/0x94) [<804f57b8>] (spin_dump+0x80/0x94) from [<804f57f8>] (spin_bug+0x2c/0x30) [<804f57f8>] (spin_bug+0x2c/0x30) from [<80222730>] (do_raw_spin_lock+0x54/0x150) [<80222730>] (do_raw_spin_lock+0x54/0x150) from [<804f96ec>] (_raw_spin_lock_irqsave+0x20/0x28) [<804f96ec>] (_raw_spin_lock_irqsave+0x20/0x28) from [<80022ea4>] (clk_enable+0x3c/0x84) [<80022ea4>] (clk_enable+0x3c/0x84) from [<8038336c>] (s5p_mfc_clock_on+0x60/0x74) [<8038336c>] (s5p_mfc_clock_on+0x60/0x74) from [<8038645c>] (s5p_mfc_read_info+0x20/0x38) [<8038645c>] (s5p_mfc_read_info+0x20/0x38) from [<8037ca3c>] (s5p_mfc_handle_frame+0x2e4/0x4bc) [<8037ca3c>] (s5p_mfc_handle_frame+0x2e4/0x4bc) from [<8037d420>] (s5p_mfc_irq+0x1ec/0x6cc) [<8037d420>] (s5p_mfc_irq+0x1ec/0x6cc) from [<8007fc74>] (handle_irq_event_percpu+0x8c/0x244) [<8007fc74>] (handle_irq_event_percpu+0x8c/0x244) from [<8007fe78>] (handle_irq_event+0x4c/0x6c) [<8007fe78>] (handle_irq_event+0x4c/0x6c) from [<80082dd8>] (handle_fasteoi_irq+0xe4/0x150) [<80082dd8>] (handle_fasteoi_irq+0xe4/0x150) from [<8007f424>] (generic_handle_irq+0x3c/0x50) [<8007f424>] (generic_handle_irq+0x3c/0x50) from [<8000f7c4>] (handle_IRQ+0x88/0xc8) [<8000f7c4>] (handle_IRQ+0x88/0xc8) from [<80008564>] (gic_handle_irq+0x44/0x68) [<80008564>] (gic_handle_irq+0x44/0x68) from [<8000e400>] (__irq_svc+0x40/0x60) Exception stack(0xef3cbe68 to 0xef3cbeb0) [<8000e400>] (__irq_svc+0x40/0x60) from [<80022cfc>] (clk_set_parent+0x30/0x74) [<80022cfc>] (clk_set_parent+0x30/0x74) from [<803ac7f8>] (set_apll.isra.0+0x28/0xb0) [<803ac7f8>] (set_apll.isra.0+0x28/0xb0) from [<803ac8e4>] (exynos5250_set_frequency+0x64/0xb8) [<803ac8e4>] (exynos5250_set_frequency+0x64/0xb8) from [<803ac280>] (exynos_target+0x1b0/0x220) [<803ac280>] (exynos_target+0x1b0/0x220) from [<803a4a0c>] (__cpufreq_driver_target+0xb0/0xd4) [<803a4a0c>] (__cpufreq_driver_target+0xb0/0xd4) from [<803aab80>] (cpufreq_interactive_updown_task+0x214/0x264) [<803aab80>] (cpufreq_interactive_updown_task+0x214/0x264) from [<80047d04>] (kthread+0x9c/0xa8) [<80047d04>] (kthread+0x9c/0xa8) from [<8000fa48>] (kernel_thread_exit+0x0/0x8) Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Suggested-by: Sunil Mazhavanchery <sunilm@samsung.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: Ben Dooks <ben-linux@fluff.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Minho Ban <mhban@samsung.com> Cc: Jaecheol Lee <jc.lee@samsung.com> Cc: Sunyoung Kang <sy0816.kang@samsung.com> Cc: Olof Johansson <olofj@chromium.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-08-27 16:42:37 +00:00
unsigned long flags;
int ret = 0;
if (IS_ERR_OR_NULL(clk) || IS_ERR_OR_NULL(parent))
return -EINVAL;
ARM: SAMSUNG: use spin_lock_irqsave() in clk_set_parent From 0cdf3aff, "ARM: SAMSUNG: use spin_lock_irqsave() in clk_{enable,disable}": The clk_enable()and clk_disable() can be used process and ISR either. And actually it is used for real product and other platforms use it now. So spin_lock_irqsave() should be used instead. We need to make a similar change in clk_set_parent(). Otherwise, you can potentially get spinlock recursion: BUG: spinlock recursion on CPU#0, kinteractive/68 lock: 807832a8, .magic: dead4ead, .owner: kinteractive/68, .owner_cpu: 0 [<80015f54>] (unwind_backtrace+0x0/0x128) from [<804f2914>] (dump_stack+0x20/0x24) [<804f2914>] (dump_stack+0x20/0x24) from [<804f57b8>] (spin_dump+0x80/0x94) [<804f57b8>] (spin_dump+0x80/0x94) from [<804f57f8>] (spin_bug+0x2c/0x30) [<804f57f8>] (spin_bug+0x2c/0x30) from [<80222730>] (do_raw_spin_lock+0x54/0x150) [<80222730>] (do_raw_spin_lock+0x54/0x150) from [<804f96ec>] (_raw_spin_lock_irqsave+0x20/0x28) [<804f96ec>] (_raw_spin_lock_irqsave+0x20/0x28) from [<80022ea4>] (clk_enable+0x3c/0x84) [<80022ea4>] (clk_enable+0x3c/0x84) from [<8038336c>] (s5p_mfc_clock_on+0x60/0x74) [<8038336c>] (s5p_mfc_clock_on+0x60/0x74) from [<8038645c>] (s5p_mfc_read_info+0x20/0x38) [<8038645c>] (s5p_mfc_read_info+0x20/0x38) from [<8037ca3c>] (s5p_mfc_handle_frame+0x2e4/0x4bc) [<8037ca3c>] (s5p_mfc_handle_frame+0x2e4/0x4bc) from [<8037d420>] (s5p_mfc_irq+0x1ec/0x6cc) [<8037d420>] (s5p_mfc_irq+0x1ec/0x6cc) from [<8007fc74>] (handle_irq_event_percpu+0x8c/0x244) [<8007fc74>] (handle_irq_event_percpu+0x8c/0x244) from [<8007fe78>] (handle_irq_event+0x4c/0x6c) [<8007fe78>] (handle_irq_event+0x4c/0x6c) from [<80082dd8>] (handle_fasteoi_irq+0xe4/0x150) [<80082dd8>] (handle_fasteoi_irq+0xe4/0x150) from [<8007f424>] (generic_handle_irq+0x3c/0x50) [<8007f424>] (generic_handle_irq+0x3c/0x50) from [<8000f7c4>] (handle_IRQ+0x88/0xc8) [<8000f7c4>] (handle_IRQ+0x88/0xc8) from [<80008564>] (gic_handle_irq+0x44/0x68) [<80008564>] (gic_handle_irq+0x44/0x68) from [<8000e400>] (__irq_svc+0x40/0x60) Exception stack(0xef3cbe68 to 0xef3cbeb0) [<8000e400>] (__irq_svc+0x40/0x60) from [<80022cfc>] (clk_set_parent+0x30/0x74) [<80022cfc>] (clk_set_parent+0x30/0x74) from [<803ac7f8>] (set_apll.isra.0+0x28/0xb0) [<803ac7f8>] (set_apll.isra.0+0x28/0xb0) from [<803ac8e4>] (exynos5250_set_frequency+0x64/0xb8) [<803ac8e4>] (exynos5250_set_frequency+0x64/0xb8) from [<803ac280>] (exynos_target+0x1b0/0x220) [<803ac280>] (exynos_target+0x1b0/0x220) from [<803a4a0c>] (__cpufreq_driver_target+0xb0/0xd4) [<803a4a0c>] (__cpufreq_driver_target+0xb0/0xd4) from [<803aab80>] (cpufreq_interactive_updown_task+0x214/0x264) [<803aab80>] (cpufreq_interactive_updown_task+0x214/0x264) from [<80047d04>] (kthread+0x9c/0xa8) [<80047d04>] (kthread+0x9c/0xa8) from [<8000fa48>] (kernel_thread_exit+0x0/0x8) Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Suggested-by: Sunil Mazhavanchery <sunilm@samsung.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: Ben Dooks <ben-linux@fluff.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Minho Ban <mhban@samsung.com> Cc: Jaecheol Lee <jc.lee@samsung.com> Cc: Sunyoung Kang <sy0816.kang@samsung.com> Cc: Olof Johansson <olofj@chromium.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-08-27 16:42:37 +00:00
spin_lock_irqsave(&clocks_lock, flags);
if (clk->ops && clk->ops->set_parent)
ret = (clk->ops->set_parent)(clk, parent);
ARM: SAMSUNG: use spin_lock_irqsave() in clk_set_parent From 0cdf3aff, "ARM: SAMSUNG: use spin_lock_irqsave() in clk_{enable,disable}": The clk_enable()and clk_disable() can be used process and ISR either. And actually it is used for real product and other platforms use it now. So spin_lock_irqsave() should be used instead. We need to make a similar change in clk_set_parent(). Otherwise, you can potentially get spinlock recursion: BUG: spinlock recursion on CPU#0, kinteractive/68 lock: 807832a8, .magic: dead4ead, .owner: kinteractive/68, .owner_cpu: 0 [<80015f54>] (unwind_backtrace+0x0/0x128) from [<804f2914>] (dump_stack+0x20/0x24) [<804f2914>] (dump_stack+0x20/0x24) from [<804f57b8>] (spin_dump+0x80/0x94) [<804f57b8>] (spin_dump+0x80/0x94) from [<804f57f8>] (spin_bug+0x2c/0x30) [<804f57f8>] (spin_bug+0x2c/0x30) from [<80222730>] (do_raw_spin_lock+0x54/0x150) [<80222730>] (do_raw_spin_lock+0x54/0x150) from [<804f96ec>] (_raw_spin_lock_irqsave+0x20/0x28) [<804f96ec>] (_raw_spin_lock_irqsave+0x20/0x28) from [<80022ea4>] (clk_enable+0x3c/0x84) [<80022ea4>] (clk_enable+0x3c/0x84) from [<8038336c>] (s5p_mfc_clock_on+0x60/0x74) [<8038336c>] (s5p_mfc_clock_on+0x60/0x74) from [<8038645c>] (s5p_mfc_read_info+0x20/0x38) [<8038645c>] (s5p_mfc_read_info+0x20/0x38) from [<8037ca3c>] (s5p_mfc_handle_frame+0x2e4/0x4bc) [<8037ca3c>] (s5p_mfc_handle_frame+0x2e4/0x4bc) from [<8037d420>] (s5p_mfc_irq+0x1ec/0x6cc) [<8037d420>] (s5p_mfc_irq+0x1ec/0x6cc) from [<8007fc74>] (handle_irq_event_percpu+0x8c/0x244) [<8007fc74>] (handle_irq_event_percpu+0x8c/0x244) from [<8007fe78>] (handle_irq_event+0x4c/0x6c) [<8007fe78>] (handle_irq_event+0x4c/0x6c) from [<80082dd8>] (handle_fasteoi_irq+0xe4/0x150) [<80082dd8>] (handle_fasteoi_irq+0xe4/0x150) from [<8007f424>] (generic_handle_irq+0x3c/0x50) [<8007f424>] (generic_handle_irq+0x3c/0x50) from [<8000f7c4>] (handle_IRQ+0x88/0xc8) [<8000f7c4>] (handle_IRQ+0x88/0xc8) from [<80008564>] (gic_handle_irq+0x44/0x68) [<80008564>] (gic_handle_irq+0x44/0x68) from [<8000e400>] (__irq_svc+0x40/0x60) Exception stack(0xef3cbe68 to 0xef3cbeb0) [<8000e400>] (__irq_svc+0x40/0x60) from [<80022cfc>] (clk_set_parent+0x30/0x74) [<80022cfc>] (clk_set_parent+0x30/0x74) from [<803ac7f8>] (set_apll.isra.0+0x28/0xb0) [<803ac7f8>] (set_apll.isra.0+0x28/0xb0) from [<803ac8e4>] (exynos5250_set_frequency+0x64/0xb8) [<803ac8e4>] (exynos5250_set_frequency+0x64/0xb8) from [<803ac280>] (exynos_target+0x1b0/0x220) [<803ac280>] (exynos_target+0x1b0/0x220) from [<803a4a0c>] (__cpufreq_driver_target+0xb0/0xd4) [<803a4a0c>] (__cpufreq_driver_target+0xb0/0xd4) from [<803aab80>] (cpufreq_interactive_updown_task+0x214/0x264) [<803aab80>] (cpufreq_interactive_updown_task+0x214/0x264) from [<80047d04>] (kthread+0x9c/0xa8) [<80047d04>] (kthread+0x9c/0xa8) from [<8000fa48>] (kernel_thread_exit+0x0/0x8) Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Suggested-by: Sunil Mazhavanchery <sunilm@samsung.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-samsung-soc@vger.kernel.org Cc: Ben Dooks <ben-linux@fluff.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Minho Ban <mhban@samsung.com> Cc: Jaecheol Lee <jc.lee@samsung.com> Cc: Sunyoung Kang <sy0816.kang@samsung.com> Cc: Olof Johansson <olofj@chromium.org> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-08-27 16:42:37 +00:00
spin_unlock_irqrestore(&clocks_lock, flags);
return ret;
}
EXPORT_SYMBOL(clk_enable);
EXPORT_SYMBOL(clk_disable);
EXPORT_SYMBOL(clk_get_rate);
EXPORT_SYMBOL(clk_round_rate);
EXPORT_SYMBOL(clk_set_rate);
EXPORT_SYMBOL(clk_get_parent);
EXPORT_SYMBOL(clk_set_parent);
/* base clocks */
int clk_default_setrate(struct clk *clk, unsigned long rate)
{
clk->rate = rate;
return 0;
}
struct clk_ops clk_ops_def_setrate = {
.set_rate = clk_default_setrate,
};
struct clk clk_xtal = {
.name = "xtal",
.rate = 0,
.parent = NULL,
.ctrlbit = 0,
};
struct clk clk_ext = {
.name = "ext",
};
struct clk clk_epll = {
.name = "epll",
};
struct clk clk_mpll = {
.name = "mpll",
.ops = &clk_ops_def_setrate,
};
struct clk clk_upll = {
.name = "upll",
.parent = NULL,
.ctrlbit = 0,
};
struct clk clk_f = {
.name = "fclk",
.rate = 0,
.parent = &clk_mpll,
.ctrlbit = 0,
};
struct clk clk_h = {
.name = "hclk",
.rate = 0,
.parent = NULL,
.ctrlbit = 0,
.ops = &clk_ops_def_setrate,
};
struct clk clk_p = {
.name = "pclk",
.rate = 0,
.parent = NULL,
.ctrlbit = 0,
.ops = &clk_ops_def_setrate,
};
struct clk clk_usb_bus = {
.name = "usb-bus",
.rate = 0,
.parent = &clk_upll,
};
struct clk s3c24xx_uclk = {
.name = "uclk",
};
/* initialise the clock system */
/**
* s3c24xx_register_clock() - register a clock
* @clk: The clock to register
*
* Add the specified clock to the list of clocks known by the system.
*/
int s3c24xx_register_clock(struct clk *clk)
{
if (clk->enable == NULL)
clk->enable = clk_null_enable;
/* fill up the clk_lookup structure and register it*/
clk->lookup.dev_id = clk->devname;
clk->lookup.con_id = clk->name;
clk->lookup.clk = clk;
clkdev_add(&clk->lookup);
return 0;
}
/**
* s3c24xx_register_clocks() - register an array of clock pointers
* @clks: Pointer to an array of struct clk pointers
* @nr_clks: The number of clocks in the @clks array.
*
* Call s3c24xx_register_clock() for all the clock pointers contained
* in the @clks list. Returns the number of failures.
*/
int s3c24xx_register_clocks(struct clk **clks, int nr_clks)
{
int fails = 0;
for (; nr_clks > 0; nr_clks--, clks++) {
if (s3c24xx_register_clock(*clks) < 0) {
struct clk *clk = *clks;
printk(KERN_ERR "%s: failed to register %p: %s\n",
__func__, clk, clk->name);
fails++;
}
}
return fails;
}
/**
* s3c_register_clocks() - register an array of clocks
* @clkp: Pointer to the first clock in the array.
* @nr_clks: Number of clocks to register.
*
* Call s3c24xx_register_clock() on the @clkp array given, printing an
* error if it fails to register the clock (unlikely).
*/
void __init s3c_register_clocks(struct clk *clkp, int nr_clks)
{
int ret;
for (; nr_clks > 0; nr_clks--, clkp++) {
ret = s3c24xx_register_clock(clkp);
if (ret < 0) {
printk(KERN_ERR "Failed to register clock %s (%d)\n",
clkp->name, ret);
}
}
}
/**
* s3c_disable_clocks() - disable an array of clocks
* @clkp: Pointer to the first clock in the array.
* @nr_clks: Number of clocks to register.
*
* for internal use only at initialisation time. disable the clocks in the
* @clkp array.
*/
void __init s3c_disable_clocks(struct clk *clkp, int nr_clks)
{
for (; nr_clks > 0; nr_clks--, clkp++)
(clkp->enable)(clkp, 0);
}
/* initialise all the clocks */
int __init s3c24xx_register_baseclocks(unsigned long xtal)
{
printk(KERN_INFO "S3C24XX Clocks, Copyright 2004 Simtec Electronics\n");
clk_xtal.rate = xtal;
/* register our clocks */
if (s3c24xx_register_clock(&clk_xtal) < 0)
printk(KERN_ERR "failed to register master xtal\n");
if (s3c24xx_register_clock(&clk_mpll) < 0)
printk(KERN_ERR "failed to register mpll clock\n");
if (s3c24xx_register_clock(&clk_upll) < 0)
printk(KERN_ERR "failed to register upll clock\n");
if (s3c24xx_register_clock(&clk_f) < 0)
printk(KERN_ERR "failed to register cpu fclk\n");
if (s3c24xx_register_clock(&clk_h) < 0)
printk(KERN_ERR "failed to register cpu hclk\n");
if (s3c24xx_register_clock(&clk_p) < 0)
printk(KERN_ERR "failed to register cpu pclk\n");
return 0;
}
#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS)
/* debugfs support to trace clock tree hierarchy and attributes */
static struct dentry *clk_debugfs_root;
static int clk_debugfs_register_one(struct clk *c)
{
int err;
struct dentry *d;
struct clk *pa = c->parent;
char s[255];
char *p = s;
p += sprintf(p, "%s", c->devname);
d = debugfs_create_dir(s, pa ? pa->dent : clk_debugfs_root);
if (!d)
return -ENOMEM;
c->dent = d;
d = debugfs_create_u8("usecount", S_IRUGO, c->dent, (u8 *)&c->usage);
if (!d) {
err = -ENOMEM;
goto err_out;
}
d = debugfs_create_u32("rate", S_IRUGO, c->dent, (u32 *)&c->rate);
if (!d) {
err = -ENOMEM;
goto err_out;
}
return 0;
err_out:
debugfs_remove_recursive(c->dent);
return err;
}
static int clk_debugfs_register(struct clk *c)
{
int err;
struct clk *pa = c->parent;
if (pa && !pa->dent) {
err = clk_debugfs_register(pa);
if (err)
return err;
}
if (!c->dent) {
err = clk_debugfs_register_one(c);
if (err)
return err;
}
return 0;
}
static int __init clk_debugfs_init(void)
{
struct clk *c;
struct dentry *d;
int err;
d = debugfs_create_dir("clock", NULL);
if (!d)
return -ENOMEM;
clk_debugfs_root = d;
list_for_each_entry(c, &clocks, list) {
err = clk_debugfs_register(c);
if (err)
goto err_out;
}
return 0;
err_out:
debugfs_remove_recursive(clk_debugfs_root);
return err;
}
late_initcall(clk_debugfs_init);
#endif /* defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS) */