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linux-next/drivers/clk/rockchip/clk-inverter.c
Shawn Lin ddd02e1456 clk: rockchip: don't return NULL when registering inverter fails
Avoid return NULL if rockchip_clk_register_inverter fails, otherwise
rockchip_clk_register_branches print "unknown clock type". The acutal
case is that it's a known clock type but we fail to regiser it, which
may makes user confuse the reason of failure.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2016-02-15 23:35:20 +01:00

113 lines
2.7 KiB
C

/*
* Copyright 2015 Heiko Stuebner <heiko@sntech.de>
*
* 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/slab.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/spinlock.h>
#include <linux/kernel.h>
#include "clk.h"
struct rockchip_inv_clock {
struct clk_hw hw;
void __iomem *reg;
int shift;
int flags;
spinlock_t *lock;
};
#define to_inv_clock(_hw) container_of(_hw, struct rockchip_inv_clock, hw)
#define INVERTER_MASK 0x1
static int rockchip_inv_get_phase(struct clk_hw *hw)
{
struct rockchip_inv_clock *inv_clock = to_inv_clock(hw);
u32 val;
val = readl(inv_clock->reg) >> inv_clock->shift;
val &= INVERTER_MASK;
return val ? 180 : 0;
}
static int rockchip_inv_set_phase(struct clk_hw *hw, int degrees)
{
struct rockchip_inv_clock *inv_clock = to_inv_clock(hw);
u32 val;
if (degrees % 180 == 0) {
val = !!degrees;
} else {
pr_err("%s: unsupported phase %d for %s\n",
__func__, degrees, clk_hw_get_name(hw));
return -EINVAL;
}
if (inv_clock->flags & ROCKCHIP_INVERTER_HIWORD_MASK) {
writel(HIWORD_UPDATE(val, INVERTER_MASK, inv_clock->shift),
inv_clock->reg);
} else {
unsigned long flags;
u32 reg;
spin_lock_irqsave(inv_clock->lock, flags);
reg = readl(inv_clock->reg);
reg &= ~BIT(inv_clock->shift);
reg |= val;
writel(reg, inv_clock->reg);
spin_unlock_irqrestore(inv_clock->lock, flags);
}
return 0;
}
static const struct clk_ops rockchip_inv_clk_ops = {
.get_phase = rockchip_inv_get_phase,
.set_phase = rockchip_inv_set_phase,
};
struct clk *rockchip_clk_register_inverter(const char *name,
const char *const *parent_names, u8 num_parents,
void __iomem *reg, int shift, int flags,
spinlock_t *lock)
{
struct clk_init_data init;
struct rockchip_inv_clock *inv_clock;
struct clk *clk;
inv_clock = kmalloc(sizeof(*inv_clock), GFP_KERNEL);
if (!inv_clock)
return ERR_PTR(-ENOMEM);
init.name = name;
init.num_parents = num_parents;
init.flags = CLK_SET_RATE_PARENT;
init.parent_names = parent_names;
init.ops = &rockchip_inv_clk_ops;
inv_clock->hw.init = &init;
inv_clock->reg = reg;
inv_clock->shift = shift;
inv_clock->flags = flags;
inv_clock->lock = lock;
clk = clk_register(NULL, &inv_clock->hw);
if (IS_ERR(clk))
kfree(inv_clock);
return clk;
}