From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751637Ab1JLGrH (ORCPT ); Wed, 12 Oct 2011 02:47:07 -0400 Received: from va3ehsobe006.messaging.microsoft.com ([216.32.180.16]:59961 "EHLO VA3EHSOBE007.bigfish.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751265Ab1JLGrF (ORCPT ); Wed, 12 Oct 2011 02:47:05 -0400 X-SpamScore: -6 X-BigFish: VS-6(zz1432N98dKc8kzz1202hzz8275bh8275dhz2dh2a8h668h839h944h61h) X-Spam-TCS-SCL: 0:0 X-Forefront-Antispam-Report: CIP:70.37.183.190;KIP:(null);UIP:(null);IPVD:NLI;H:mail.freescale.net;RD:none;EFVD:NLI X-FB-SS: 0, Date: Wed, 12 Oct 2011 14:46:47 +0800 From: Richard Zhao To: Mike Turquette CC: , , , , , , , , , , , , , , Jamie Iles , , , , , , Subject: Re: [PATCH v2 4/7] clk: Add simple gated clock Message-ID: <20111012064646.GA31037@b20223-02.ap.freescale.net> References: <1316730422-20027-1-git-send-email-mturquette@ti.com> <1316730422-20027-5-git-send-email-mturquette@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <1316730422-20027-5-git-send-email-mturquette@ti.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-OriginatorOrg: freescale.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 22, 2011 at 03:26:59PM -0700, Mike Turquette wrote: > From: Jeremy Kerr > > Signed-off-by: Jeremy Kerr > Signed-off-by: Mark Brown > Signed-off-by: Jamie Iles > Signed-off-by: Mike Turquette > --- > Changes since v1: > Add copyright header > Fold in Jamie's patch for set-to-disable clks > Use BIT macro instead of shift > > drivers/clk/Kconfig | 4 ++ > drivers/clk/Makefile | 1 + > drivers/clk/clk-gate.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/clk.h | 13 ++++++++ > 4 files changed, 96 insertions(+), 0 deletions(-) > create mode 100644 drivers/clk/clk-gate.c I feel hard to tell the tree the clk parent, at register/init time. For the simple gate clk, the only way is to set .get_parent. But normally, for clk without any divider we set .get_parent to NULL. Maybe we can put .parent to struct clk_hw? Thanks Richard > > diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig > index d8313d7..a78967c 100644 > --- a/drivers/clk/Kconfig > +++ b/drivers/clk/Kconfig > @@ -12,3 +12,7 @@ config GENERIC_CLK > config GENERIC_CLK_FIXED > bool > depends on GENERIC_CLK > + > +config GENERIC_CLK_GATE > + bool > + depends on GENERIC_CLK > diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile > index 9a3325a..d186446 100644 > --- a/drivers/clk/Makefile > +++ b/drivers/clk/Makefile > @@ -2,3 +2,4 @@ > obj-$(CONFIG_CLKDEV_LOOKUP) += clkdev.o > obj-$(CONFIG_GENERIC_CLK) += clk.o > obj-$(CONFIG_GENERIC_CLK_FIXED) += clk-fixed.o > +obj-$(CONFIG_GENERIC_CLK_GATE) += clk-gate.o > diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c > new file mode 100644 > index 0000000..a1d8e79 > --- /dev/null > +++ b/drivers/clk/clk-gate.c > @@ -0,0 +1,78 @@ > +/* > + * Copyright (C) 2010-2011 Canonical Ltd > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + * Simple clk gate implementation > + */ > + > +#include > +#include > +#include > + > +#define to_clk_gate(clk) container_of(clk, struct clk_gate, hw) > + > +static unsigned long clk_gate_get_rate(struct clk_hw *clk) > +{ > + return clk_get_rate(clk_get_parent(clk->clk)); > +} > + > +static void clk_gate_set_bit(struct clk_hw *clk) > +{ > + struct clk_gate *gate = to_clk_gate(clk); > + u32 reg; > + > + reg = __raw_readl(gate->reg); > + reg |= BIT(gate->bit_idx); > + __raw_writel(reg, gate->reg); > +} > + > +static void clk_gate_clear_bit(struct clk_hw *clk) > +{ > + struct clk_gate *gate = to_clk_gate(clk); > + u32 reg; > + > + reg = __raw_readl(gate->reg); > + reg &= ~BIT(gate->bit_idx); > + __raw_writel(reg, gate->reg); > +} > + > +static int clk_gate_enable_set(struct clk_hw *clk) > +{ > + clk_gate_set_bit(clk); > + > + return 0; > +} > + > +static void clk_gate_disable_clear(struct clk_hw *clk) > +{ > + clk_gate_clear_bit(clk); > +} > + > +struct clk_hw_ops clk_gate_set_enable_ops = { > + .recalc_rate = clk_gate_get_rate, > + .enable = clk_gate_enable_set, > + .disable = clk_gate_disable_clear, > +}; > +EXPORT_SYMBOL_GPL(clk_gate_set_enable_ops); > + > +static int clk_gate_enable_clear(struct clk_hw *clk) > +{ > + clk_gate_clear_bit(clk); > + > + return 0; > +} > + > +static void clk_gate_disable_set(struct clk_hw *clk) > +{ > + clk_gate_set_bit(clk); > +} > + > +struct clk_hw_ops clk_gate_set_disable_ops = { > + .recalc_rate = clk_gate_get_rate, > + .enable = clk_gate_enable_clear, > + .disable = clk_gate_disable_set, > +}; > +EXPORT_SYMBOL_GPL(clk_gate_set_disable_ops); > diff --git a/include/linux/clk.h b/include/linux/clk.h > index 1903dd8..626fd0d 100644 > --- a/include/linux/clk.h > +++ b/include/linux/clk.h > @@ -124,6 +124,19 @@ extern struct clk_hw_ops clk_fixed_ops; > > #endif /* CONFIG_GENERIC_CLK_FIXED */ > > +#ifdef CONFIG_GENERIC_CLK_GATE > + > +struct clk_gate { > + struct clk_hw hw; > + void __iomem *reg; > + u8 bit_idx; > +}; > + > +extern struct clk_hw_ops clk_gate_set_enable_ops; > +extern struct clk_hw_ops clk_gate_set_disable_ops; > + > +#endif /* CONFIG_GENERIC_CLK_GATE */ > + > /** > * clk_register - register and initialize a new clock > * > -- > 1.7.4.1 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >