From mboxrd@z Thu Jan  1 00:00:00 1970
From: adrian.wenl@gmail.com (Lei Wen)
Date: Thu, 19 Apr 2012 15:26:53 +0800
Subject: [PATCH 23/40] ARM i.MX: Add common clock support for 2bit gate
In-Reply-To: <20120419070032.GA22773@b20223-02.ap.freescale.net>
References: <1334065553-7565-1-git-send-email-s.hauer@pengutronix.de>
 <1334065553-7565-24-git-send-email-s.hauer@pengutronix.de>
 <20120419070032.GA22773@b20223-02.ap.freescale.net>
Message-ID: <CALZhoSTTTuwSEv8snhMpuTqU_L5DC3zRW97ePazLqS9SfdZAPA@mail.gmail.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Thu, Apr 19, 2012 at 3:00 PM, Shawn Guo <shawn.guo@freescale.com> wrote:
> On Tue, Apr 10, 2012 at 03:45:36PM +0200, Sascha Hauer wrote:
> [snip]
>> +struct clk *clk_register_gate2(struct device *dev, const char *name,
>> + ? ? ? ? ? ? const char *parent_name, unsigned long flags,
>> + ? ? ? ? ? ? void __iomem *reg, u8 bit_idx,
>> + ? ? ? ? ? ? u8 clk_gate2_flags, spinlock_t *lock)
>> +{
>> + ? ? struct clk_gate *gate;
>> + ? ? struct clk *clk;
>> +
>> + ? ? gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
>> +
>> + ? ? if (!gate) {
>> + ? ? ? ? ? ? pr_err("%s: could not allocate gated clk\n", __func__);
>> + ? ? ? ? ? ? return NULL;
>> + ? ? }
>> +
>> + ? ? /* struct clk_gate assignments */
>> + ? ? gate->reg = reg;
>> + ? ? gate->bit_idx = bit_idx;
>> + ? ? gate->flags = clk_gate2_flags;
>> + ? ? gate->lock = lock;
>> +
>> + ? ? if (parent_name) {
>> + ? ? ? ? ? ? gate->parent[0] = kstrdup(parent_name, GFP_KERNEL);
>> + ? ? ? ? ? ? if (!gate->parent[0])
>> + ? ? ? ? ? ? ? ? ? ? goto out;
>> + ? ? }
>> +
>> + ? ? clk = clk_register(dev, name,
>> + ? ? ? ? ? ? ? ? ? ? &clk_gate2_ops, &gate->hw,
>> + ? ? ? ? ? ? ? ? ? ? gate->parent,
>> + ? ? ? ? ? ? ? ? ? ? (parent_name ? 1 : 0),
>> + ? ? ? ? ? ? ? ? ? ? flags);
> Why do you re-use struct clk_gate while you don't use clk_gate_ops?
> It doesn't follow object oriented thought. struct clk_gate may change
> according to clk_gate_ops changes.
>
> Thanks
> Richard
>
>
>

Why not expend original clk-gate.c to allow set more than one bit a
time to gate that clock?
At least in my platform, some clock need 12bit to get its gate mode,
which means that module
has more than one clock concurrently up to work, and only a part of
that group work cannot lead
to a correct working mode. This also means those bits need to turn
on/off at the same time.

Thanks,
Lei