From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757179Ab2EBUL5 (ORCPT ); Wed, 2 May 2012 16:11:57 -0400 Received: from mail-ob0-f174.google.com ([209.85.214.174]:49294 "EHLO mail-ob0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757097Ab2EBUL4 convert rfc822-to-8bit (ORCPT ); Wed, 2 May 2012 16:11:56 -0400 MIME-Version: 1.0 In-Reply-To: <20120502073331.GS4141@pengutronix.de> References: <1335924760-796-1-git-send-email-rob.lee@linaro.org> <1335924760-796-3-git-send-email-rob.lee@linaro.org> <20120502073331.GS4141@pengutronix.de> From: Rob Lee Date: Wed, 2 May 2012 15:11:35 -0500 Message-ID: Subject: Re: [PATCH v2 2/3] ARM: imx: Add imx5 cpuidle driver To: Sascha Hauer Cc: kernel@pengutronix.de, shawn.guo@linaro.org, amit.kucheria@linaro.org, daniel.lezcano@linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linaro-dev@lists.linaro.org, patches@linaro.org, jj@chaosbits.net Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sascha, On Wed, May 2, 2012 at 2:33 AM, Sascha Hauer wrote: > On Tue, May 01, 2012 at 09:12:39PM -0500, Robert Lee wrote: >> Add imx5 cpuidle driver. >> >> Signed-off-by: Robert Lee >> --- >>  arch/arm/mach-imx/mm-imx5.c |   42 +++++++++++++++++++++++++++++++++++++++--- >>  1 file changed, 39 insertions(+), 3 deletions(-) >> >> diff --git a/arch/arm/mach-imx/mm-imx5.c b/arch/arm/mach-imx/mm-imx5.c >> index d6b7e9f..cbd9bad 100644 >> --- a/arch/arm/mach-imx/mm-imx5.c >> +++ b/arch/arm/mach-imx/mm-imx5.c >> @@ -22,24 +22,59 @@ >>  #include >>  #include >>  #include >> +#include >> >>  static struct clk *gpc_dvfs_clk; >> >> -static void imx5_idle(void) >> +static int imx5_idle(void) >>  { >> +     int ret = 0; >> + >>       /* gpc clock is needed for SRPG */ >>       if (gpc_dvfs_clk == NULL) { >>               gpc_dvfs_clk = clk_get(NULL, "gpc_dvfs"); >>               if (IS_ERR(gpc_dvfs_clk)) >> -                     return; >> +                     return -ENODEV; >>       } >>       clk_enable(gpc_dvfs_clk); >>       mx5_cpu_lp_set(WAIT_UNCLOCKED_POWER_OFF); >>       if (!tzic_enable_wake()) >>               cpu_do_idle(); >> +     else >> +             ret = -EBUSY; >>       clk_disable(gpc_dvfs_clk); >> + >> +     return ret; >> +} >> + >> +static int imx5_cpuidle_enter(struct cpuidle_device *dev, >> +                             struct cpuidle_driver *drv, int idx) >> +{ >> +     int ret; >> + >> +     ret = imx5_idle(); >> + >> +     if (ret < 0) >> +             return ret; >> + >> +     return idx; >>  } >> >> +static struct cpuidle_driver imx5_cpuidle_driver = { >> +     .name                   = "imx5_cpuidle", >> +     .owner                  = THIS_MODULE, >> +     .en_core_tk_irqen       = 1, >> +     .states[0]      = { >> +             .enter                  = imx5_cpuidle_enter, >> +             .exit_latency           = 20, /* max latency at 160MHz */ >> +             .target_residency       = 1, >> +             .flags                  = CPUIDLE_FLAG_TIME_VALID, >> +             .name                   = "IMX5 SRPG", >> +             .desc                   = "CPU state retained,powered off", >> +     }, >> +     .state_count            = 1, >> +}; >> + >>  /* >>   * Define the MX50 memory map. >>   */ >> @@ -103,7 +138,7 @@ void __init imx51_init_early(void) >>       mxc_set_cpu_type(MXC_CPU_MX51); >>       mxc_iomux_v3_init(MX51_IO_ADDRESS(MX51_IOMUXC_BASE_ADDR)); >>       mxc_arch_reset_init(MX51_IO_ADDRESS(MX51_WDOG1_BASE_ADDR)); >> -     arm_pm_idle = imx5_idle; >> +     arm_pm_idle = (void *)imx5_idle; > > I don't like this. It will cover all warnings when the prototype of > arm_pm_idle changes in future. Better add a static void imx5_idle > which calls a static int imx5_do_idle, then you have an idle function > which returns an int. > What about using the following: arm_pm_idle = (void (*)(void))imx5_idle; This will give warnings if arm_pm_idle prototype changes. Thanks, Rob >>  } >> >>  void __init imx53_init_early(void) >> @@ -238,4 +273,5 @@ void __init imx53_soc_init(void) >>  void __init imx51_init_late(void) >>  { >>       mx51_neon_fixup(); >> +     imx_cpuidle_init(&imx5_cpuidle_driver); >>  } >> -- >> 1.7.10 >> >> > > -- > Pengutronix e.K.                           |                             | > Industrial Linux Solutions                 | http://www.pengutronix.de/  | > Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    | > Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |