linux/arch/arm/mach-msm/clock.c
Brian Swetland 600f7cfebe [ARM] msm: clock: provide clk_*() api support for
Makes use of the proc_comm interface to provide clock control on
MSM7X01A family SoCs.

Signed-off-by: Brian Swetland <swetland@google.com>
2008-10-22 02:41:00 -07:00

218 lines
4.8 KiB
C

/* arch/arm/mach-msm/clock.c
*
* Copyright (C) 2007 Google, Inc.
* Copyright (c) 2007 QUALCOMM Incorporated
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* 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/version.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/spinlock.h>
#include "clock.h"
#include "proc_comm.h"
static DEFINE_MUTEX(clocks_mutex);
static DEFINE_SPINLOCK(clocks_lock);
static LIST_HEAD(clocks);
/*
* glue for the proc_comm interface
*/
static inline int pc_clk_enable(unsigned id)
{
return msm_proc_comm(PCOM_CLKCTL_RPC_ENABLE, &id, NULL);
}
static inline void pc_clk_disable(unsigned id)
{
msm_proc_comm(PCOM_CLKCTL_RPC_DISABLE, &id, NULL);
}
static inline int pc_clk_set_rate(unsigned id, unsigned rate)
{
return msm_proc_comm(PCOM_CLKCTL_RPC_SET_RATE, &id, &rate);
}
static inline int pc_clk_set_min_rate(unsigned id, unsigned rate)
{
return msm_proc_comm(PCOM_CLKCTL_RPC_MIN_RATE, &id, &rate);
}
static inline int pc_clk_set_max_rate(unsigned id, unsigned rate)
{
return msm_proc_comm(PCOM_CLKCTL_RPC_MAX_RATE, &id, &rate);
}
static inline int pc_clk_set_flags(unsigned id, unsigned flags)
{
return msm_proc_comm(PCOM_CLKCTL_RPC_SET_FLAGS, &id, &flags);
}
static inline unsigned pc_clk_get_rate(unsigned id)
{
if (msm_proc_comm(PCOM_CLKCTL_RPC_RATE, &id, NULL))
return 0;
else
return id;
}
static inline unsigned pc_clk_is_enabled(unsigned id)
{
if (msm_proc_comm(PCOM_CLKCTL_RPC_ENABLED, &id, NULL))
return 0;
else
return id;
}
static inline int pc_pll_request(unsigned id, unsigned on)
{
on = !!on;
return msm_proc_comm(PCOM_CLKCTL_RPC_PLL_REQUEST, &id, &on);
}
/*
* Standard clock functions defined in include/linux/clk.h
*/
struct clk *clk_get(struct device *dev, const char *id)
{
struct clk *clk;
mutex_lock(&clocks_mutex);
list_for_each_entry(clk, &clocks, list)
if (!strcmp(id, clk->name) && clk->dev == dev)
goto found_it;
list_for_each_entry(clk, &clocks, list)
if (!strcmp(id, clk->name) && clk->dev == NULL)
goto found_it;
clk = ERR_PTR(-ENOENT);
found_it:
mutex_unlock(&clocks_mutex);
return clk;
}
EXPORT_SYMBOL(clk_get);
void clk_put(struct clk *clk)
{
}
EXPORT_SYMBOL(clk_put);
int clk_enable(struct clk *clk)
{
unsigned long flags;
spin_lock_irqsave(&clocks_lock, flags);
clk->count++;
if (clk->count == 1)
pc_clk_enable(clk->id);
spin_unlock_irqrestore(&clocks_lock, flags);
return 0;
}
EXPORT_SYMBOL(clk_enable);
void clk_disable(struct clk *clk)
{
unsigned long flags;
spin_lock_irqsave(&clocks_lock, flags);
BUG_ON(clk->count == 0);
clk->count--;
if (clk->count == 0)
pc_clk_disable(clk->id);
spin_unlock_irqrestore(&clocks_lock, flags);
}
EXPORT_SYMBOL(clk_disable);
unsigned long clk_get_rate(struct clk *clk)
{
return pc_clk_get_rate(clk->id);
}
EXPORT_SYMBOL(clk_get_rate);
int clk_set_rate(struct clk *clk, unsigned long rate)
{
int ret;
if (clk->flags & CLKFLAG_USE_MIN_MAX_TO_SET) {
ret = pc_clk_set_max_rate(clk->id, rate);
if (ret)
return ret;
return pc_clk_set_min_rate(clk->id, rate);
}
return pc_clk_set_rate(clk->id, rate);
}
EXPORT_SYMBOL(clk_set_rate);
int clk_set_parent(struct clk *clk, struct clk *parent)
{
return -ENOSYS;
}
EXPORT_SYMBOL(clk_set_parent);
struct clk *clk_get_parent(struct clk *clk)
{
return ERR_PTR(-ENOSYS);
}
EXPORT_SYMBOL(clk_get_parent);
int clk_set_flags(struct clk *clk, unsigned long flags)
{
if (clk == NULL || IS_ERR(clk))
return -EINVAL;
return pc_clk_set_flags(clk->id, flags);
}
EXPORT_SYMBOL(clk_set_flags);
void __init msm_clock_init(void)
{
unsigned n;
spin_lock_init(&clocks_lock);
mutex_lock(&clocks_mutex);
for (n = 0; n < msm_num_clocks; n++)
list_add_tail(&msm_clocks[n].list, &clocks);
mutex_unlock(&clocks_mutex);
}
/* The bootloader and/or AMSS may have left various clocks enabled.
* Disable any clocks that belong to us (CLKFLAG_AUTO_OFF) but have
* not been explicitly enabled by a clk_enable() call.
*/
static int __init clock_late_init(void)
{
unsigned long flags;
struct clk *clk;
unsigned count = 0;
mutex_lock(&clocks_mutex);
list_for_each_entry(clk, &clocks, list) {
if (clk->flags & CLKFLAG_AUTO_OFF) {
spin_lock_irqsave(&clocks_lock, flags);
if (!clk->count) {
count++;
pc_clk_disable(clk->id);
}
spin_unlock_irqrestore(&clocks_lock, flags);
}
}
mutex_unlock(&clocks_mutex);
pr_info("clock_late_init() disabled %d unused clocks\n", count);
return 0;
}
late_initcall(clock_late_init);