Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756162Ab3JRUJV (ORCPT ); Fri, 18 Oct 2013 16:09:21 -0400 Received: from mail-vb0-f49.google.com ([209.85.212.49]:33040 "EHLO mail-vb0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753902Ab3JRUJT (ORCPT ); Fri, 18 Oct 2013 16:09:19 -0400 MIME-Version: 1.0 In-Reply-To: <52610273.3080005@samsung.com> References: <1381876762-10892-1-git-send-email-dianders@chromium.org> <1381876762-10892-2-git-send-email-dianders@chromium.org> <52610273.3080005@samsung.com> Date: Fri, 18 Oct 2013 13:09:18 -0700 X-Google-Sender-Auth: kSwFs4eBGFwOr6ZIfyzdZP-7JCg Message-ID: Subject: Re: [PATCH 1/2] mmc: dw_mmc: Cleanup disable of low power mode w/ SDIO interrupts From: Doug Anderson To: Jaehoon Chung Cc: Chris Ball , Seungwon Jeon , James Hogan , Grant Grundler , Alim Akhtar , Abhilash Kesavan , Tomasz Figa , Olof Johansson , Sonny Rao , Bing Zhao , "linux-mmc@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2204 Lines: 50 Jaehoon, On Fri, Oct 18, 2013 at 2:42 AM, Jaehoon Chung wrote: >> - clk_en_a = mci_readl(host, CLKENA); >> + /* >> + * Low power mode will stop the card clock when idle. According to the >> + * description of the CLKENA register we should disable low power mode >> + * for SDIO cards if we need SDIO interrupts to work. >> + */ >> + if (mmc->caps | MMC_CAP_SDIO_IRQ) { > mmc->caps & MMC_CAP_SDIO_IRQ? Wow, that was an embarrassing one. Thanks. >> + const u32 clken_low_pwr = SDMMC_CLKEN_LOW_PWR << slot->id; >> + u32 clk_en_a_old; >> + u32 clk_en_a; >> >> - if (clk_en_a & clken_low_pwr) { >> - mci_writel(host, CLKENA, clk_en_a & ~clken_low_pwr); >> - mci_send_cmd(slot, SDMMC_CMD_UPD_CLK | >> - SDMMC_CMD_PRV_DAT_WAIT, 0); >> + clk_en_a_old = mci_readl(host, CLKENA); >> + >> + if (card->type == MMC_TYPE_SDIO || >> + card->type == MMC_TYPE_SD_COMBO) { >> + set_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags); >> + clk_en_a = clk_en_a_old & ~clken_low_pwr; >> + } else { >> + clear_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags); >> + clk_en_a = clk_en_a_old | clken_low_pwr; > When this condition is entered? card->type is always MMC_TYPE_SDIO or MMC_TYPE_SD_COMBO, isn't? Ugh, that's not intuitive. This callback is only called for SDIO cards and not MMC/SD cards? That means if you plug in an SDIO card and then eject it and plug in an SD card you won't get to low power. Hrm. I dug around a bit and couldn't find a better way to do this and then I realized that the other user of the init_card() callback has the same bug, so for the next version of the series I'm proposing a fix for mmc core to add this for all types. If you have a better suggestion, I'm all ears. -Doug -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/